WorldWideScience

Sample records for enable fuel efficiency

  1. Intermediate Alcohol-Gasoline Blends, Fuels for Enabling Increased Engine Efficiency and Powertrain Possibilities

    Energy Technology Data Exchange (ETDEWEB)

    Splitter, Derek A [ORNL; Szybist, James P [ORNL

    2014-01-01

    The present study experimentally investigates spark-ignited combustion with 87 AKI E0 gasoline in its neat form and in mid-level alcohol-gasoline blends with 24% vol./vol. iso-butanol-gasoline (IB24) and 30% vol./vol. ethanol-gasoline (E30). A single-cylinder research engine is used with a low and high compression ratio of 9.2:1 and 11.85:1 respectively. The engine is equipped with hydraulically actuated valves, laboratory intake air, and is capable of external exhaust gas recirculation (EGR). All fuels are operated to full-load conditions with =1, using both 0% and 15% external cooled EGR. The results demonstrate that higher octane number bio-fuels better utilize higher compression ratios with high stoichiometric torque capability. Specifically, the unique properties of ethanol enabled a doubling of the stoichiometric torque capability with the 11.85:1 compression ratio using E30 as compared to 87 AKI, up to 20 bar IMEPg at =1 (with 15% EGR, 18.5 bar with 0% EGR). EGR was shown to provide thermodynamic advantages with all fuels. The results demonstrate that E30 may further the downsizing and downspeeding of engines by achieving increased low speed torque, even with high compression ratios. The results suggest that at mid-level alcohol-gasoline blends, engine and vehicle optimization can offset the reduced fuel energy content of alcohol-gasoline blends, and likely reduce vehicle fuel consumption and tailpipe CO2 emissions.

  2. Emission Control Research to Enable Fuel Efficiency: Department of Energy Heavy Vehicle Technologies

    International Nuclear Information System (INIS)

    Gurpreet Singh; Ronald L. Graves; John M. Storey; William P. Partridge; John F. Thomas; Bernie M. Penetrante; Raymond M. Brusasco; Bernard T. Merritt; George E. Vogtlin; Christopher L. Aardahl; Craig F. Habeger; M.L. Balmer

    2000-01-01

    The Office of Heavy Vehicle Technologies supports research to enable high-efficiency diesel engines to meet future emissions regulations, thus clearing the way for their use in light trucks as well as continuing as the most efficient powerplant for freight-haulers. Compliance with Tier 2 rules and expected heavy duty engine standards will require effective exhaust emission controls (after-treatment) for diesels in these applications. DOE laboratories are working with industry to improve emission control technologies in projects ranging from application of new diagnostics for elucidating key mechanisms, to development and tests of prototype devices. This paper provides an overview of these R and D efforts, with examples of key findings and developments

  3. Integrated membrane and microbial fuel cell technologies for enabling energy-efficient effluent Re-use in power plants.

    Science.gov (United States)

    Shrestha, Namita; Chilkoor, Govinda; Xia, Lichao; Alvarado, Catalina; Kilduff, James E; Keating, John J; Belfort, Georges; Gadhamshetty, Venkataramana

    2017-06-15

    Municipal wastewater is an attractive alternative to freshwater sources to meet the cooling water needs of thermal power plants. Here we offer an energy-efficient integrated microbial fuel cell (MFC)/ultrafiltration (UF) process to purify primary clarifier effluent from a municipal wastewater treatment plant for use as cooling water. The microbial fuel cell was shown to significantly reduce chemical oxygen demand (COD) in the primary settled wastewater effluent upstream of the UF module, while eliminating the energy demand required to deliver dissolved oxygen in conventional aerobic treatment. We investigated surface modification of the UF membranes to control fouling. Two promising hydrophilic monomers were identified in a high-throughput search: zwitterion (2-(Methacryloyloxy)-ethyl-dimethyl-(3-sulfopropyl ammoniumhydroxide, abbreviated BET SO 3 - ), and amine (2-(Methacryloyloxy) ethyl trimethylammonium chloride, abbreviated N(CH 3 ) 3 + ). Monomers were grafted using UV-induced polymerization on commercial poly (ether sulfone) membranes. Filtration of MFC effluent by membranes modified with BET SO 3 - and N(CH 3 ) 3 + exhibited a lower rate of resistance increase and lower energy consumption than the commercially available membrane. The MFC/UF process produced high quality cooling water that meets the Electrical Power Research Institute (EPRI) recommendations for COD, a suite of metals (Fe, Al, Cu, Zn, Si, Mn, S, Ca and Mg), and offered extremely low corrosion rates (<0.05 mm/yr). A series of AC and DC diagnostic tests were used to evaluate the MFC performance. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Bioblendstocks that Enable High Efficiency Engine Designs

    Energy Technology Data Exchange (ETDEWEB)

    McCormick, Robert L.; Fioroni, Gina M.; Ratcliff, Matthew A.; Zigler, Bradley T.; Farrell, John

    2016-11-03

    The past decade has seen a high level of innovation in production of biofuels from sugar, lipid, and lignocellulose feedstocks. As discussed in several talks at this workshop, ethanol blends in the E25 to E50 range could enable more highly efficient spark-ignited (SI) engines. This is because of their knock resistance properties that include not only high research octane number (RON), but also charge cooling from high heat of vaporization, and high flame speed. Emerging alcohol fuels such as isobutanol or mixed alcohols have desirable properties such as reduced gasoline blend vapor pressure, but also have lower RON than ethanol. These fuels may be able to achieve the same knock resistance benefits, but likely will require higher blend levels or higher RON hydrocarbon blendstocks. A group of very high RON (>150) oxygenates such as dimethyl furan, methyl anisole, and related compounds are also produced from biomass. While providing no increase in charge cooling, their very high octane numbers may provide adequate knock resistance for future highly efficient SI engines. Given this range of options for highly knock resistant fuels there appears to be a critical need for a fuel knock resistance metric that includes effects of octane number, heat of vaporization, and potentially flame speed. Emerging diesel fuels include highly branched long-chain alkanes from hydroprocessing of fats and oils, as well as sugar-derived terpenoids. These have relatively high cetane number (CN), which may have some benefits in designing more efficient CI engines. Fast pyrolysis of biomass can produce diesel boiling range streams that are high in aromatic, oxygen and acid contents. Hydroprocessing can be applied to remove oxygen and consequently reduce acidity, however there are strong economic incentives to leave up to 2 wt% oxygen in the product. This oxygen will primarily be present as low CN alkyl phenols and aryl ethers. While these have high heating value, their presence in diesel fuel

  5. Fuel properties to enable lifted-flame combustion

    Energy Technology Data Exchange (ETDEWEB)

    Kurtz, Eric [Ford Motor Company, Dearborn, MI (United States)

    2015-03-15

    The Fuel Properties to Enable Lifted-Flame Combustion project responded directly to solicitation DE-FOA-0000239 AOI 1A, Fuels and Lubricants for Advanced Combustion Regimes. This subtopic was intended to encompass clean and highly-efficient, liquid-fueled combustion engines to achieve extremely low engine-out nitrogen oxides (NOx) and particulate matter (PM) as a target and similar efficiency as state-of-the-art direct injection diesel engines. The intent of this project was to identify how fuel properties can be used to achieve controllable Leaner Lifted Flame Combustion (LLFC) with low NOx and PM emissions. Specifically, this project was expected to identify and test key fuel properties to enable LLFC and their compatibility with current fuel systems and to enhance combustion models to capture the effect of fuel properties on advanced combustion. Successful demonstration of LLFC may reduce the need for after treatment devices, thereby reducing costs and improving thermal efficiency. The project team consisted of key technical personnel from Ford Motor Company (FMC), the University of Wisconsin-Madison (UW), Sandia National Laboratories (SNL) and Lawrence Livermore National Laboratories (LLNL). Each partner had key roles in achieving project objectives. FMC investigated fuel properties relating to LLFC and sooting tendency. Together, FMC and UW developed and integrated 3D combustion models to capture fuel property combustion effects. FMC used these modeling results to develop a combustion system and define fuel properties to support a single-cylinder demonstration of fuel-enabled LLFC. UW investigated modeling the flame characteristics and emissions behavior of different fuels, including those with different cetane number and oxygen content. SNL led spray combustion experiments to quantify the effect of key fuel properties on combustion characteristics critical for LLFC, as well as single cylinder optical engine experiments to improve fundamental

  6. Automotive fuel efficiency

    International Nuclear Information System (INIS)

    Abelson, P.H.

    1992-01-01

    For at least the remainder of this century, the United States faces a growing dependence on imported oil. Costs are substantial, and they will mount. In June 1992, net imports provided nearly 50% of supplies, and their cost was $4.3 billion. Cost of net imports of motor vehicles and parts amounted to $3.0 billion. The two items combined totaled more than the negative trade balance of $6.6 billion. The light-duty highway fleet alone accounted for 38.2% of U.S. oil consumption in 1988. Correspondingly, the fleet was a substantial emitter of air pollutants - NO x , CO, and nonmethane hydrocarbons. In addition, it was a major source of CO 2 . The twin problems of oil imports and pollution would be ameliorated if the fuel economy if cars and trucks could be improved and their emissions were also reduced. In principle, the mileage of US automobiles could be substantially improved. But on purchasing a car, U.S. buyers rank fuel efficiency eight when making their choice. They are attracted to options that lower mileage. Consumers also tend to prefer large cars over small ones for reasons of safety. Increasingly, buyers are purchasing light trucks and vans that have inferior fuel efficiency. As a result of the above trends, the average mileage of the US automotive fleet has been diminishing. As long as fuel is available at comparatively low prices and there is no federal requirement for better mileage, improvement is unlikely. Moreover, even if improvements were mandated, change would be slow

  7. Transport Studies Enabling Efficiency Optimization of Cost-Competitive Fuel Cell Stacks (aka AURORA: Areal Use and Reactant Optimization at Rated Amperage)

    Energy Technology Data Exchange (ETDEWEB)

    Conti, Amedeo [Nuvera Fuel Cells, Inc., Billerica, MA (United States); Dross, Robert [Nuvera Fuel Cells, Inc., Billerica, MA (United States)

    2013-12-06

    Hydrogen fuel cells are recognized as one of the most viable solutions for mobility in the 21st century; however, there are technical challenges that must be addressed before the technology can become available for mass production. One of the most demanding aspects is the costs of present-day fuel cells which are prohibitively high for the majority of envisioned markets. The fuel cell community recognizes two major drivers to an effective cost reduction: (1) decreasing the noble metals content, and (2) increasing the power density in order to reduce the number of cells needed to achieve a specified power level. To date, the majority of development work aimed at increasing the value metric (i.e. W/mg-Pt) has focused on the reduction of precious metal loadings, and this important work continues. Efforts to increase power density have been limited by two main factors: (1) performance limitations associated with mass transport barriers, and (2) the historical prioritization of efficiency over cost. This program is driven by commercialization imperatives, and challenges both of these factors. The premise of this Program, supported by proprietary cost modeling by Nuvera, is that DOE 2015 cost targets can be met by simultaneously exceeding DOE 2015 targets for Platinum loadings (using materials with less than 0.2 mg-Pt/cm2) and MEA power density (operating at higher than 1.0 Watt/cm2). The approach of this program is to combine Nuvera’s stack technology, which has demonstrated the ability to operate stably at high current densities (> 1.5 A/cm2), with low Platinum loading MEAs developed by Johnson Matthey in order to maximize Pt specific power density and reduce stack cost. A predictive performance model developed by PSU/UTK is central to the program allowing the team to study the physics and optimize materials/conditions specific to low Pt loading electrodes and ultra-high current density and operation.

  8. Enabling alternate fuels for commercial aircraft

    OpenAIRE

    Daggett, D.

    2010-01-01

    The following reports on the past four years of work to examine the feasibility, sustainability and economic viability of developing a renewable, greenhouse-gas-neutral, liquid biofuel for commercial aircraft. The sharp increase in environmental concerns, such as global warming, as well as the volatile price fluctuations of fossil fuels, has ignited a search for alternative transportation fuels. However, commercial aircraft can not use present alternative fuels that are designed for ground...

  9. Framing car fuel efficiency : linearity heuristic for fuel consumption and fuel-efficiency ratings

    NARCIS (Netherlands)

    Schouten, T.M.; Bolderdijk, J.W.; Steg, L.

    2014-01-01

    People are sensitive to the way information on fuel efficiency is conveyed. When the fuel efficiency of cars is framed in terms of fuel per distance (FPD; e.g. l/100 km), instead of distance per units of fuel (DPF; e.g. km/l), people have a more accurate perception of potential fuel savings. People

  10. Materials Approach to Fuel Efficient Tires

    Energy Technology Data Exchange (ETDEWEB)

    Votruba-Drzal, Peter [PPG Industries, Monroeville, PA (United States); Kornish, Brian [PPG Industries, Monroeville, PA (United States)

    2015-06-30

    The objective of this project was to design, develop, and demonstrate fuel efficient and safety regulation compliant tire filler and barrier coating technologies that will improve overall fuel efficiency by at least 2%. The program developed and validated two complementary approaches to improving fuel efficiency through tire improvements. The first technology was a modified silica-based product that is 15% lower in cost and/or enables a 10% improvement in tread wear while maintaining the already demonstrated minimum of 2% improvement in average fuel efficiency. The second technology was a barrier coating with reduced oxygen transmission rate compared to the state-of-the-art halobutyl rubber inner liners that will provide extended placarded tire pressure retention at significantly reduced material usage. A lower-permeance, thinner inner liner coating which retains tire pressure was expected to deliver the additional 2% reduction in fleet fuel consumption. From the 2006 Transportation Research Board Report1, a 10 percent reduction in rolling resistance can reduce consumer fuel expenditures by 1 to 2 percent for typical vehicles. This savings is equivalent to 6 to 12 gallons per year. A 1 psi drop in inflation pressure increases the tire's rolling resistance by about 1.4 percent.

  11. Biofunctionalized conductive polymers enable efficient CO2 electroreduction

    Science.gov (United States)

    Coskun, Halime; Aljabour, Abdalaziz; De Luna, Phil; Farka, Dominik; Greunz, Theresia; Stifter, David; Kus, Mahmut; Zheng, Xueli; Liu, Min; Hassel, Achim W.; Schöfberger, Wolfgang; Sargent, Edward H.; Sariciftci, Niyazi Serdar; Stadler, Philipp

    2017-01-01

    Selective electrocatalysts are urgently needed for carbon dioxide (CO2) reduction to replace fossil fuels with renewable fuels, thereby closing the carbon cycle. To date, noble metals have achieved the best performance in energy yield and faradaic efficiency and have recently reached impressive electrical-to-chemical power conversion efficiencies. However, the scarcity of precious metals makes the search for scalable, metal-free, CO2 reduction reaction (CO2RR) catalysts all the more important. We report an all-organic, that is, metal-free, electrocatalyst that achieves impressive performance comparable to that of best-in-class Ag electrocatalysts. We hypothesized that polydopamine—a conjugated polymer whose structure incorporates hydrogen-bonded motifs found in enzymes—could offer the combination of efficient electrical conduction, together with rendered active catalytic sites, and potentially thereby enable CO2RR. Only by developing a vapor-phase polymerization of polydopamine were we able to combine the needed excellent conductivity with thin film–based processing. We achieve catalytic performance with geometric current densities of 18 mA cm−2 at 0.21 V overpotential (−0.86 V versus normal hydrogen electrode) for the electrosynthesis of C1 species (carbon monoxide and formate) with continuous 16-hour operation at >80% faradaic efficiency. Our catalyst exhibits lower overpotentials than state-of-the-art formate-selective metal electrocatalysts (for example, 0.5 V for Ag at 18 mA cm−1). The results confirm the value of exploiting hydrogen-bonded sequences as effective catalytic centers for renewable and cost-efficient industrial CO2RR applications. PMID:28798958

  12. Modeling of hybrid vehicle fuel economy and fuel engine efficiency

    Science.gov (United States)

    Wu, Wei

    "Near-CV" (i.e., near-conventional vehicle) hybrid vehicles, with an internal combustion engine, and a supplementary storage with low-weight, low-energy but high-power capacity, are analyzed. This design avoids the shortcoming of the "near-EV" and the "dual-mode" hybrid vehicles that need a large energy storage system (in terms of energy capacity and weight). The small storage is used to optimize engine energy management and can provide power when needed. The energy advantage of the "near-CV" design is to reduce reliance on the engine at low power, to enable regenerative braking, and to provide good performance with a small engine. The fuel consumption of internal combustion engines, which might be applied to hybrid vehicles, is analyzed by building simple analytical models that reflect the engines' energy loss characteristics. Both diesel and gasoline engines are modeled. The simple analytical models describe engine fuel consumption at any speed and load point by describing the engine's indicated efficiency and friction. The engine's indicated efficiency and heat loss are described in terms of several easy-to-obtain engine parameters, e.g., compression ratio, displacement, bore and stroke. Engine friction is described in terms of parameters obtained by fitting available fuel measurements on several diesel and spark-ignition engines. The engine models developed are shown to conform closely to experimental fuel consumption and motored friction data. A model of the energy use of "near-CV" hybrid vehicles with different storage mechanism is created, based on simple algebraic description of the components. With powertrain downsizing and hybridization, a "near-CV" hybrid vehicle can obtain a factor of approximately two in overall fuel efficiency (mpg) improvement, without considering reductions in the vehicle load.

  13. Increasing Fuel Efficiency of Direct Methanol Fuel Cell Systems with Feedforward Control of the Operating Concentration

    Directory of Open Access Journals (Sweden)

    Youngseung Na

    2015-09-01

    Full Text Available Most of the R&D on fuel cells for portable applications concentrates on increasing efficiencies and energy densities to compete with other energy storage devices, especially batteries. To improve the efficiency of direct methanol fuel cell (DMFC systems, several modifications to system layouts and operating strategies are considered in this paper, rather than modifications to the fuel cell itself. Two modified DMFC systems are presented, one with an additional inline mixer and a further modification of it with a separate tank to recover condensed water. The set point for methanol concentration control in the solution is determined by fuel efficiency and varies with the current and other process variables. Feedforward concentration control enables variable concentration for dynamic loads. Simulation results were validated experimentally with fuel cell systems.

  14. Fuel cell research: Towards efficient energy

    CSIR Research Space (South Africa)

    Rohwer, MB

    2008-11-01

    Full Text Available fuel cells by optimising the loading of catalyst (being expensive noble metals) and ionomer; 2) Improving conventional acidic direct alcohol fuel cells by developing more efficient catalysts and by investigating other fuels than methanol; 3... these components add significantly to the overall cost of a PEMFC. 1 We focused our research activities on: 1) The effect of the loading of catalytic ink on cell performance; 2) The effect of the ionomer content in the catalytic ink; 3) Testing...

  15. Fuel Efficiency Assessment with DEA

    Science.gov (United States)

    2010-03-01

    weighted with regard to their relative importance. The weights are subjectively de - fined by subject experts, which makes the FEI vulnerable to...Energy Information Administration, Imports, Exports and Movements. The US government consumes only a small amount of fuel/energy of the US de - mand...it takes every measure to conserve energy and this is stated in their mission statement. Gen. Arthur J. Lichte stated AMC’s new five focus areas as

  16. Greater Sudbury fuel efficient driving handbook

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-12-15

    Reducing the amount of fuel that people use for personal driving saves money, improves local air quality, and reduces personal contributions to climate change. This handbook was developed to be used as a tool for a fuel efficient driving pilot program in Greater Sudbury in 2009-2010. Specifically, the purpose of the handbook was to provide greater Sudbury drivers with information on how to drive and maintain their personal vehicles in order to maximize fuel efficiency. The handbook also provides tips for purchasing fuel efficient vehicles. It outlines the benefits of fuel maximization, with particular reference to reducing contributions to climate change; reducing emissions of air pollutants; safe driving; and money savings. Some tips for efficient driving are to avoid aggressive driving; use cruise control; plan trips; and remove excess weight. Tips for efficient winter driving are to avoid idling to warm up the engine; use a block heater; remove snow and ice; use snow tires; and check tire pressure. The importance of car maintenance and tire pressure was emphasized. The handbook also explains how fuel consumption ratings are developed by vehicle manufacturers. refs., figs.

  17. Functionalized Graphene Enables Highly Efficient Solar Thermal Steam Generation.

    Science.gov (United States)

    Yang, Junlong; Pang, Yunsong; Huang, Weixin; Shaw, Scott K; Schiffbauer, Jarrod; Pillers, Michelle Anne; Mu, Xin; Luo, Shirui; Zhang, Teng; Huang, Yajiang; Li, Guangxian; Ptasinska, Sylwia; Lieberman, Marya; Luo, Tengfei

    2017-06-27

    The ability to efficiently utilize solar thermal energy to enable liquid-to-vapor phase transition has great technological implications for a wide variety of applications, such as water treatment and chemical fractionation. Here, we demonstrate that functionalizing graphene using hydrophilic groups can greatly enhance the solar thermal steam generation efficiency. Our results show that specially functionalized graphene can improve the overall solar-to-vapor efficiency from 38% to 48% at one sun conditions compared to chemically reduced graphene oxide. Our experiments show that such an improvement is a surface effect mainly attributed to the more hydrophilic feature of functionalized graphene, which influences the water meniscus profile at the vapor-liquid interface due to capillary effect. This will lead to thinner water films close to the three-phase contact line, where the water surface temperature is higher since the resistance of thinner water film is smaller, leading to more efficient evaporation. This strategy of functionalizing graphene to make it more hydrophilic can be potentially integrated with the existing macroscopic heat isolation strategies to further improve the overall solar-to-vapor conversion efficiency.

  18. The Transforming Mobility Ecosystem: Enabling in Energy-Efficient Future

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2017-01-31

    Over the next decade, the transportation sector is poised for rapid change, propelled toward a new mobility future by strong technology currents and the confluence of prevailing megatrends. These major forces hold the promise of shaping a new mobility future – one that unlocks tremendous economic value, provides unprecedented gains in safety, offers affordable and equal accessibility, and enables the transition to energy-efficient transport of people and goods. They come, however, with cautionary viewpoints on energy consumption of the entire sector, necessitating the need to carefully guide the emergent future. This report examines four possible mobility futures that could exist in 2050 and the positive and negative impacts of these futures on energy consumption and the broader economy.

  19. Fuel efficient stoves for the Third World

    Energy Technology Data Exchange (ETDEWEB)

    Watts, P [Intermediate Technology Group Ltd., Rugby (GB)

    1990-12-01

    In developing countries particularly in rural areas, the majority of households depend on biomass fuels such as wood, charcoal, or animal dung for their cooking and heating needs. Formerly free, these materials are acquiring a monetary value and improved combustion efficiency leads to better utilisation as well as reduced pollution. This article describes the latest development in this field. (author).

  20. Fuel Flexible Combustion Systems for High-Efficiency Utilization of Opportunity Fuels in Gas Turbines

    Energy Technology Data Exchange (ETDEWEB)

    Venkatesan, Krishna

    2011-11-30

    The purpose of this program was to develop low-emissions, efficient fuel-flexible combustion technology which enables operation of a given gas turbine on a wider range of opportunity fuels that lie outside of current natural gas-centered fuel specifications. The program encompasses a selection of important, representative fuels of opportunity for gas turbines with widely varying fundamental properties of combustion. The research program covers conceptual and detailed combustor design, fabrication, and testing of retrofitable and/or novel fuel-flexible gas turbine combustor hardware, specifically advanced fuel nozzle technology, at full-scale gas turbine combustor conditions. This project was performed over the period of October 2008 through September 2011 under Cooperative Agreement DE-FC26-08NT05868 for the U.S. Department of Energy/National Energy Technology Laboratory (USDOE/NETL) entitled "Fuel Flexible Combustion Systems for High-Efficiency Utilization of Opportunity Fuels in Gas Turbines". The overall objective of this program was met with great success. GE was able to successfully demonstrate the operability of two fuel-flexible combustion nozzles over a wide range of opportunity fuels at heavy-duty gas turbine conditions while meeting emissions goals. The GE MS6000B ("6B") gas turbine engine was chosen as the target platform for new fuel-flexible premixer development. Comprehensive conceptual design and analysis of new fuel-flexible premixing nozzles were undertaken. Gas turbine cycle models and detailed flow network models of the combustor provide the premixer conditions (temperature, pressure, pressure drops, velocities, and air flow splits) and illustrate the impact of widely varying fuel flow rates on the combustor. Detailed chemical kinetic mechanisms were employed to compare some fundamental combustion characteristics of the target fuels, including flame speeds and lean blow-out behavior. Perfectly premixed combustion experiments were conducted to

  1. Light and Heavy Tactical Wheeled Vehicle Fuel Consumption Evaluations Using Fuel Efficient Gear Oils (FEGO)

    Science.gov (United States)

    2016-05-01

    UNCLASSIFIED LIGHT AND HEAVY TACTICAL WHEELED VEHICLE FUEL CONSUMPTION EVALUATIONS USING FUEL EFFICIENT GEAR OILS (FEGO) FINAL... HEAVY TACTICAL WHEELED VEHICLE FUEL CONSUMPTION EVALUATIONS USING FUEL EFFICIENT GEAR OILS (FEGO) FINAL REPORT TFLRF No. 477 by Adam C...August 2014 – March 2016 4. TITLE AND SUBTITLE LIGHT AND HEAVY TACTICAL WHEELED VEHICLE FUEL CONSUMPTION EVALUATIONS USING FEUL EFFICIENT GEAR OILS

  2. Stochastic Synapses Enable Efficient Brain-Inspired Learning Machines

    Science.gov (United States)

    Neftci, Emre O.; Pedroni, Bruno U.; Joshi, Siddharth; Al-Shedivat, Maruan; Cauwenberghs, Gert

    2016-01-01

    Recent studies have shown that synaptic unreliability is a robust and sufficient mechanism for inducing the stochasticity observed in cortex. Here, we introduce Synaptic Sampling Machines (S2Ms), a class of neural network models that uses synaptic stochasticity as a means to Monte Carlo sampling and unsupervised learning. Similar to the original formulation of Boltzmann machines, these models can be viewed as a stochastic counterpart of Hopfield networks, but where stochasticity is induced by a random mask over the connections. Synaptic stochasticity plays the dual role of an efficient mechanism for sampling, and a regularizer during learning akin to DropConnect. A local synaptic plasticity rule implementing an event-driven form of contrastive divergence enables the learning of generative models in an on-line fashion. S2Ms perform equally well using discrete-timed artificial units (as in Hopfield networks) or continuous-timed leaky integrate and fire neurons. The learned representations are remarkably sparse and robust to reductions in bit precision and synapse pruning: removal of more than 75% of the weakest connections followed by cursory re-learning causes a negligible performance loss on benchmark classification tasks. The spiking neuron-based S2Ms outperform existing spike-based unsupervised learners, while potentially offering substantial advantages in terms of power and complexity, and are thus promising models for on-line learning in brain-inspired hardware. PMID:27445650

  3. Cornell Fuel Cell Institute: Materials Discovery to Enable Fuel Cell Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Abruna, H.D.; DiSalvo, Francis J.

    2012-06-29

    The discovery and understanding of new, improved materials to advance fuel cell technology are the objectives of the Cornell Fuel Cell Institute (CFCI) research program. CFCI was initially formed in 2003. This report highlights the accomplishments from 2006-2009. Many of the grand challenges in energy science and technology are based on the need for materials with greatly improved or even revolutionary properties and performance. This is certainly true for fuel cells, which have the promise of being highly efficient in the conversion of chemical energy to electrical energy. Fuel cells offer the possibility of efficiencies perhaps up to 90 % based on the free energy of reaction. Here, the challenges are clearly in the materials used to construct the heart of the fuel cell: the membrane electrode assembly (MEA). The MEA consists of two electrodes separated by an ionically conducting membrane. Each electrode is a nanocomposite of electronically conducting catalyst support, ionic conductor and open porosity, that together form three percolation networks that must connect to each catalyst nanoparticle; otherwise the catalyst is inactive. This report highlights the findings of the three years completing the CFCI funding, and incudes developments in materials for electrocatalyts, catalyst supports, materials with structured and functional porosity for electrodes, and novel electrolyte membranes. The report also discusses developments at understanding electrocatalytic mechanisms, especially on novel catalyst surfaces, plus in situ characterization techniques and contributions from theory. Much of the research of the CFCI continues within the Energy Materials Center at Cornell (emc2), a DOE funded, Office of Science Energy Frontier Research Center (EFRC).

  4. Hydrogen utilization efficiency in PEM fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Metkemeyer, R; Achard, P; Rouveyre, L; Picot, D [Ecole des Mines de Paris, Centre D' energrtique, Sophia Antipolis (France)

    1998-07-01

    In this paper, we present the work carried out within the framework of the FEVER project (Fuel cell Electric Vehicle for Efficiency and Range), an European project coordinated by Renault, joining Ecole des Mines de Paris, Ansaldo, De Nora, Air Liquide and Volvo. For the FEVER project, where an electrical air compressor is used for oxidant supply, there is no need for hydrogen spill over, meaning that the hydrogen stoichiometry has to be as close to one as possible. To determine the optimum hydrogen utilization efficiency for a 10 kW Proton Exchange Membrane Fuel Cell (PEMFC) fed with pure hydrogen, a 4 kW prototype fuel cell was tested with and without a hydrogen recirculator at the test facility of Ecole des Mines de Paris. Nitrogen cross over from the cathodic compartment to the anodic compartment limits the hydrogen utilization of the fuel cell without recirculator to 97.4 % whereas 100% is feasible when a recirculator is used. 5 refs.

  5. High Efficiency Reversible Fuel Cell Power Converter

    DEFF Research Database (Denmark)

    Pittini, Riccardo

    as well as different dc-ac and dc-dc converter topologies are presented and analyzed. A new ac-dc topology for high efficiency data center applications is proposed and an efficiency characterization based on the fuel cell stack I-V characteristic curve is presented. The second part discusses the main...... converter components. Wide bandgap power semiconductors are introduced due to their superior performance in comparison to traditional silicon power devices. The analysis presents a study based on switching loss measurements performed on Si IGBTs, SiC JFETs, SiC MOSFETs and their respective gate drivers...

  6. A Fuel-Efficient Conflict Resolution Maneuver for Separation Assurance

    Science.gov (United States)

    Bowe, Aisha Ruth; Santiago, Confesor

    2012-01-01

    Automated separation assurance algorithms are envisioned to play an integral role in accommodating the forecasted increase in demand of the National Airspace System. Developing a robust, reliable, air traffic management system involves safely increasing efficiency and throughput while considering the potential impact on users. This experiment seeks to evaluate the benefit of augmenting a conflict detection and resolution algorithm to consider a fuel efficient, Zero-Delay Direct-To maneuver, when resolving a given conflict based on either minimum fuel burn or minimum delay. A total of twelve conditions were tested in a fast-time simulation conducted in three airspace regions with mixed aircraft types and light weather. Results show that inclusion of this maneuver has no appreciable effect on the ability of the algorithm to safely detect and resolve conflicts. The results further suggest that enabling the Zero-Delay Direct-To maneuver significantly increases the cumulative fuel burn savings when choosing resolution based on minimum fuel burn while marginally increasing the average delay per resolution.

  7. Fuel Efficiency in AWD-system

    OpenAIRE

    Fredriksson, Robert; Trkulja, Milovan

    2008-01-01

    This degree project has been made in cooperation with engineers working for GM Engineering/Saab Automobile AB in Trollhättan. The given name by Saab for the project is “Fuel efficiency improvements in All Wheel Drive(AWD)-system”. The main tasks of this thesis work were to investigate the size of the power losses in different parts on the propeller shaft, to design a computer program that calculates coordinates and angles on a propeller shaft and to investigate the possibilities to put togeth...

  8. Semiconductors enable efficient solutions in electric vehicles; Halbleiter ermoeglichen effiziente Loesungen in Elektrofahrzeugen

    Energy Technology Data Exchange (ETDEWEB)

    Adlkofer, Hans [Infineon Technologies AG, Muenchen (Germany)

    2010-07-01

    The automotive industry currently enters a new phase of the competition. The successful addressing of vehicles with electric motors is in the focus of he competition. Electric vehicles which save the electrical energy in batteries may not replace immediately all fuel-powered vehicles in the given transport infrastructure. The semiconductor industry needs to provide solutions and technologies in order to increase the efficiency of electric vehicles and further to reduce the operating costs. Thus, the author of the contribution under consideration reports on possible ways to this target using a battery balancing system considering the amortization of such a system. The presented active battery cell management system may monitor the charging and discharging of the battery by means of a software monitor so that an energy recovery system is supported optimally. It ensures a reliable operation, prevents accidental premature battery failure and enables cost savings of about 10 % for the whole set of batteries.

  9. Microporous Cokes Formed in Zeolite Catalysts Enable Efficient Solar Evaporation

    KAUST Repository

    Wang, Jianjian

    2017-03-13

    Cokes are inevitably generated during zeolite-catalyzed reactions as deleterious side products that deactivate the catalyst. In this study, we in-situ converted cokes into carbons within the confined microporous zeolite structures and evaluated their performances as absorbing materials for solar-driven water evaporation. With a properly chosen zeolite, the cokederived carbons possessed ordered interconnected pores and tunable compositions. We found that the porous structure and the oxygen content in as-prepared carbons had important influences on their energy conversion efficiencies. Among various investigated carbon materials, the carbon derived from the methanol-to-olefins reaction over zeolite Beta gave the highest conversion efficiency of 72% under simulated sunlight with equivalent solar intensity of 2 suns. This study not only demonstrates the great potential of traditionally useless cokes for solar thermal applications but also provides new insights into the design of carbon-based absorbing materials for efficient solar evaporation.

  10. Fuel-efficient driveline systems; Kraftstoffsparende Antriebssysteme

    Energy Technology Data Exchange (ETDEWEB)

    Greiner, J. [ZF Getriebe GmbH, Kressbronn (Germany); Vahlensieck, B.; Mohr, M.; Casals, P. [ZF Friedrichshafen AG, Friedrichshafen (Germany)

    2009-07-01

    Passenger car automatic transmissions in transducer planet construction and double clutch construction developed to an important differentiation characteristic for the manufacturers of vehicles. While for the 1950ies traditionally over 90 % of customers in the U.S.A. and Japan prefer the automatic transmission, still recently, in the European market the automatic transmission almost exclusively were reserved to the premium automobiles with 6-cylinder engines, 8 cylinder engines and 12 cylinder engines. On the one hand, this was due to the high additional costs for the special equipment 'automatic transmission'. On the other hand, this also was due to the image of this kind of gear construction which was said to be very comfortably, above all using great amount of fuel and unsportsmanlike. This fundamentally changed with the introduction of automatic transmissions with up to eight gears and high translation spreading as well as with the extremely sporty double clutch transmissions. By means of optimized starting elements, intelligent arrangement of the wheel sets and efficiently working electro hydraulic controls, engineers succeeded in placing transmissions which differ both in cycle consumption and in real consumption only marginally from a manual transmission. With consideration of the immensely increasing fuel costs it is to be considered that on the basis of these automatic transmissions micro hybrid designs, mild hybrid designs and full hybrid designs as so-called parallel hybrid systems are introduced into the powertrain in a great extent. Thereby, the range of function is reaches from the asynchronous operation system with micro hybrid system over recuperation and boosting with mild hybrid system till to electrical driving with a full hybrid system. The contribution under consideration shows the influence of the individual systems on the fuel consumption on the basis of the transmission system portfolio and the hybrid system portfolio of ZF

  11. Enabling affordable and efficiently deployed location based smart home systems.

    Science.gov (United States)

    Kelly, Damian; McLoone, Sean; Dishongh, Terry

    2009-01-01

    With the obvious eldercare capabilities of smart environments it is a question of "when", rather than "if", these technologies will be routinely integrated into the design of future houses. In the meantime, health monitoring applications must be integrated into already complete home environments. However, there is significant effort involved in installing the hardware necessary to monitor the movements of an elder throughout an environment. Our work seeks to address the high infrastructure requirements of traditional location-based smart home systems by developing an extremely low infrastructure localisation technique. A study of the most efficient method of obtaining calibration data for an environment is conducted and different mobile devices are compared for localisation accuracy and cost trade-off. It is believed that these developments will contribute towards more efficiently deployed location-based smart home systems.

  12. Modulation of sulfur metabolism enables efficient glucosinolate engineering

    Directory of Open Access Journals (Sweden)

    Geu-Flores Fernando

    2011-01-01

    Full Text Available Abstract Background Metabolic engineering in heterologous organisms is an attractive approach to achieve efficient production of valuable natural products. Glucosinolates represent a good example of such compounds as they are thought to be the cancer-preventive agents in cruciferous plants. We have recently demonstrated that it is feasible to engineer benzylglucosinolate (BGLS in the non-cruciferous plant Nicotiana benthamiana by transient expression of five genes from Arabidopsis thaliana. In the same study, we showed that co-expression of a sixth Arabidopsis gene, γ-glutamyl peptidase 1 (GGP1, resolved a metabolic bottleneck, thereby increasing BGLS accumulation. However, the accumulation did not reach the expected levels, leaving room for further optimization. Results To optimize heterologous glucosinolate production, we have in this study performed a comparative metabolite analysis of BGLS-producing N. benthamiana leaves in the presence or absence of GGP1. The analysis revealed that the increased BGLS levels in the presence of GGP1 were accompanied by a high accumulation of the last intermediate, desulfoBGLS, and a derivative thereof. This evidenced a bottleneck in the last step of the pathway, the transfer of sulfate from 3'-phosphoadenosine-5'-phosphosulfate (PAPS to desulfoBGLS by the sulfotransferase AtSOT16. While substitution of AtSOT16 with alternative sulfotransferases did not alleviate the bottleneck, experiments with the three genes involved in the formation and recycling of PAPS showed that co-expression of adenosine 5'-phosphosulfate kinase 2 (APK2 alone reduced the accumulation of desulfoBGLS and its derivative by more than 98% and increased BGLS accumulation 16-fold. Conclusion Adjusting sulfur metabolism by directing sulfur from primary to secondary metabolism leads to a remarkable improvement in BGLS accumulation and thereby represents an important step towards a clean and efficient production of glucosinolates in

  13. CERAMIC MEMBRANE ENABLING TECHNOLOGY FOR IMPROVED IGCC EFFICIENCY

    International Nuclear Information System (INIS)

    Ravi Prasad

    2000-01-01

    The objective of this program is to conduct a technology development program to advance the state-of-the-art in ceramic Oxygen Transport Membranes (OTM) to the level required to produce step change improvements in process economics, efficiency, and environmental benefits for commercial IGCC systems and other applications. The IGCC program is focused on addressing key issues in materials, processing, manufacturing, engineering and system development that will make the OTM a commercial reality. The objective of the OTM materials development task is to identify a suitable material that can be formed into a thin film to produce the target oxygen flux. This requires that the material have an adequate permeation rate, and thermo-mechanical and thermo-chemical properties such that the material is able to be supported on the desired substrate and sufficient mechanical strength to survive the stresses involved in operation. The objective of the composite OTM development task is to develop the architecture and fabrication techniques necessary to construct stable, high performance, thin film OTMs supported on suitable porous, load bearing substrates. The objective of the process development task of this program to demonstrate the program objectives on a single OTM tube under test conditions simulating those of the optimum process cycle for the power plant

  14. Automobile Buyer Decisions about Fuel Economy and Fuel Efficiency

    OpenAIRE

    Kurani, Ken; Turrentine, Thomas

    2004-01-01

    Much prior research into consumer automotive and fuel purchase behaviors and fuel economy has been shaped by the normative assumptions of economics. Among these assumptions are that consumers should pay attention to costs of fuel and that they are aware of their options to save on fuel over long periods of time, i.e., the life of a vehicle or at least their period of ownership. For example, researchers have analyzed in some depth consumer choices for more fuel economical vehicles in the 1980s...

  15. Criticality impacts on LWR fuel storage efficiency

    International Nuclear Information System (INIS)

    Napolitano, D.

    1992-01-01

    This presentation discusses the criticality impacts throughout storage of fuel onsite including new fuel storage, spent fuel storage, consolidation, and dry storage. The general principles for criticality safety are also be discussed. There is first an introduction which explains today's situation for criticality safety concerns. This is followed by a discussion of criticality safety Regulatory Guides, safety limits and fundamental principles. Design objectives for criticality safety in the 1990's include higher burnups, longer cycles, and higher enrichments which impact the criticality safety design. Criticality safety for new fuel storage, spent fuel storage, fuel consolidation, and dry storage are followed by conclusions. Today's situation is one in which the US does not reprocess, and does not have an operating MRS facility or repository. High density fuel storage rack designs of the 1980s, are filling up. Dry cask storage systems for spent fuel storage are being utilized. Enrichments continue to increase PWR fuel assemblies with enrichments of 4.5 to 5.0 weight percent U-235 and BWR fuel assemblies with enrichments of 3.25 to 3.5 weight percent U-235 are common. Criticality concerns affect the capacity and the economics of light water reactor (LWR) fuel storage arrays by dictating the spacing of fuel assemblies in a storage system, or the use of poisons or exotic materials in the storage system design

  16. The role of fuel cells and electrolysers in future efficient energy systems

    DEFF Research Database (Denmark)

    Hendriksen, Peter Vang; Vad Mathiesen, Brian; Pedersen, Allan Schrøder

    2012-01-01

    Fuel cells can increase the efficiency of the energy system and electrolysers can help enable a de-carbonisation of the energy supply. In this chapter we explain the role of fuel cells in future energy systems together with the role of electrolysers in smart energy systems with increasing penetra...... penetrations of intermittent renewable resources in the electricity grid increases the demand for smart energy systems.......Fuel cells can increase the efficiency of the energy system and electrolysers can help enable a de-carbonisation of the energy supply. In this chapter we explain the role of fuel cells in future energy systems together with the role of electrolysers in smart energy systems with increasing...

  17. 75 FR 15893 - Tire Fuel Efficiency Consumer Information Program

    Science.gov (United States)

    2010-03-30

    ... how much the proposed consumer information program would affect consumer tire purchasing behavior and... 575 Tire Fuel Efficiency Consumer Information Program; Final Rule #0;#0;Federal Register / Vol. 75, No... 2127-AK45 Tire Fuel Efficiency Consumer Information Program AGENCY: National Highway Traffic Safety...

  18. Technological growth of fuel efficiency in european automobile market 1975–2015

    International Nuclear Information System (INIS)

    Hu, Kejia; Chen, Yuche

    2016-01-01

    This paper looks at the technological growth of new car fleet fuel efficiency in the European Union between 1975 and 2015. According to the analysis results, from1975 to 2006 the fuel efficiency technology improvements were largely offset by vehicles' increased weight, engine size, and consumer amenities such as acceleration capacity. After 2006, downsizing in weight and engine capacity was observed in new car fleet, while fuel consumption decreased by 32% between 2006 and 2015. We adopt a statistical method and find that from 1975 to 2015, a 1% increase in weight would result in 0.3 to 0.5% increments in fuel consumption per 100 km, and a 1% reduction in 0–100 km/h acceleration time would increase fuel consumption by about 0.3%. Impacts of other attributes on fuel consumption are also assessed. To meet the European Union's 2021 fuel consumption target, downsizing of cars, as well as at least maintaining fuel efficiency technology growth trend observed between 2005 and 2015, are needed. Government policies on controlling improvement in acceleration performance or promoting alternative fuel vehicles are also important to achieve European Union 2021 target. - Highlights: • We evaluated fuel efficiency technological growth trends in European cars. • We quantified trade-offs between vehicle attributes and fuel consumption using statistical methods. • Technology development was offset by upsizing and upgrading of cars in 1975–2006. • Technology development and downsizing enabled large improvements in efficiency in 2006–2015. • Maintaining historical trend of efficiency improvement is not enough to achieve EU 2021 target.

  19. On the efficiency of an advanced automotive fuel cell system

    Energy Technology Data Exchange (ETDEWEB)

    Buechi, F.N.; Freunberger, S.A.; Reum, M.; Tsukada, A.; Dietrich, P. [Paul Scherrer Institut, Electrochemistry Laboratory, CH-5232 Villigen PSI (Switzerland); Paganelli, G.; Delfino, A. [Conception et Developpement Michelin, Route Andre-Piller 30, CH-1762 Givisiez (Switzerland)

    2007-04-15

    Efficiency is the key parameter for the application of fuel cells in automotive applications. The efficiency of a hydrogen/oxygen polymer electrolyte fuel cell system is analyzed and compared to hydrogen/air systems. The analysis is performed for the tank to electric power chain. Furthermore, the additional energy required for using pure oxygen as a second fuel is analyzed and included in the calculation. The results show that if hydrogen is produced from primary fossil energy carriers, such as natural gas and pure oxygen needs to be obtained by a conventional process; the fuel to electric current efficiency is comparable for hydrogen/oxygen and hydrogen/air systems. However, if hydrogen and oxygen are produced by the splitting of water, i.e., by electrolysis or by a thermochemical process, the fuel to electric current efficiency for the hydrogen/oxygen system is clearly superior. (Abstract Copyright [2007], Wiley Periodicals, Inc.)

  20. Modelling the effects of transport policy levers on fuel efficiency and national fuel consumption

    International Nuclear Information System (INIS)

    Kirby, H.R.; Hutton, B.; McQuaid, R.W.; Napier Univ., Edinburgh; Raeside, R.; Napier Univ., Edinburgh; Zhang, Xiayoan; Napier Univ., Edinburgh

    2000-01-01

    The paper provides an overview of the main features of a Vehicle Market Model (VMM) which estimates changes to vehicle stock/kilometrage, fuel consumed and CO 2 emitted. It is disaggregated into four basic vehicle types. The model includes: the trends in fuel consumption of new cars, including the role of fuel price: a sub-model to estimate the fuel consumption of vehicles on roads characterised by user-defined driving cycle regimes; procedures that reflect distribution of traffic across different area/road types; and the ability to vary the speed (or driving cycle) from one year to another, or as a result of traffic growth. The most significant variable influencing fuel consumption of vehicles was consumption in the previous year, followed by dummy variables related to engine size. the time trend (a proxy for technological improvements), and then fuel price. Indeed the effect of fuel price on car fuel efficiency was observed to be insignificant (at the 95% level) in two of the three versions of the model, and the size of fuel price term was also the smallest. This suggests that the effectiveness of using fuel prices as a direct policy tool to reduce fuel consumption may he limited. Fuel prices may have significant indirect impacts (such as influencing people to purchase more fuel efficient cars and vehicle manufacturers to invest in developing fuel efficient technology) as may other factors such as the threat of legislation. (Author)

  1. Fuel-Efficient Road Vehicle Non-Engine Components

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    The need to address global energy issues, i.e. energy security and climate change, is more urgent than ever. Road vehicles dominate global oil consumption and are one of the fastest growing energy end-uses. This paper studies policies and measures to improve on-road fuel efficiency of vehicles by focusing on energy efficiency of automobile components not generally considered in official fuel efficiency test, namely tyres, cooling technologies and lightings. In this paper, current policies and industry activities on these components are reviewed, fuel saving potential by the components analysed and possible policies to realise the potential recommended.

  2. Performance and fuel conversion efficiency of a spark ignition engine fueled with iso-butanol

    International Nuclear Information System (INIS)

    Irimescu, Adrian

    2012-01-01

    Highlights: ► Iso-butanol use in a port injection spark ignition engine. ► Fuel conversion efficiency calculated based on chassis dynamometer measurements. ► Combined study of engine efficiency and air–fuel mixture temperature. ► Excellent running characteristics with minor fuel system modifications. ► Up to 11% relative drop in part load efficiency due to incomplete fuel vaporization. -- Abstract: Alcohols are increasingly used as fuels for spark ignition engines. While ethanol is most commonly used, long chain alcohols such as butanol feature several advantages like increased heating value and reduced corrosive action. This study investigated the effect of fueling a port injection engine with iso-butanol, as compared to gasoline operation. Performance levels were maintained within the same limits as with the fossil fuel without modifications to any engine component. An additional electronic module was used for increasing fuel flow by extending the injection time. Fuel conversion efficiency decreased when the engine was fueled with iso-butanol by up to 9% at full load and by up to 11% at part load, calculated as relative values. Incomplete fuel evaporation was identified as the factor most likely to cause the drop in engine efficiency.

  3. Review of International Policies for Vehicle Fuel Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    This paper reviews past and current voluntary and regulatory fuel efficiency programs and then assesses the effectiveness of these policies from the viewpoints of enforcement, standard design, standard stringency and standard related policies.

  4. Estimation of Gasoline Price Elasticities of Demand for Automobile Fuel Efficiency in Korea: A Hedonic Approach

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sung Tae [Sungkyunkwan University, Seoul (Korea); Lee, Myunghun [Keimyung University, Taegu (Korea)

    2001-03-01

    This paper estimates the gasoline price elasticities of demand for automobile fuel efficiency in Korea to examine indirectly whether the government policy of raising fuel prices is effective in inducing less consumption of fuel, relying on a hedonic technique developed by Atkinson and Halvorsen (1984). One of the advantages of this technique is that the data for a single year, without involving variation in the price of gasoline, is sufficient in implementing this study. Moreover, this technique enables us to circumvent the multicollinearity problem, which had reduced reliability of the results in previous hedonic studies. The estimated elasticities of demand for fuel efficiency with respect to the price of gasoline, on average, is 0.42. (author). 30 refs., 3 tabs.

  5. Autonomy-Enabled Fuel Savings for Military Vehicles: Report on 2016 Aberdeen Test Center Testing

    Energy Technology Data Exchange (ETDEWEB)

    Ragatz, Adam [National Renewable Energy Lab. (NREL), Golden, CO (United States); Prohaska, Robert [National Renewable Energy Lab. (NREL), Golden, CO (United States); Gonder, Jeff [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2017-05-26

    Fuel savings have never been the primary focus for autonomy-enabled military vehicles. However, studies have estimated that autonomy in passenger and commercial vehicles could improve fuel economy by as much as 22%-33% over various drive cycles. If even a fraction of this saving could be realized in military vehicles, significant cost savings could be realized each year through reduced fuel transport missions, reduced fuel purchases, less maintenance, fewer required personnel, and increased vehicle range. Researchers from the National Renewable Energy Laboratory installed advanced data logging equipment and instrumentation on two autonomy-enabled convoy vehicles configured with Lockheed Martin's Autonomous Mobility Applique System to determine system performance and improve on the overall vehicle control strategies of the vehicles. Initial test results from testing conducted at the U.S. Army Aberdeen Test Center at the Aberdeen Proving Grounds are included in this report. Lessons learned from in-use testing and performance results have been provided to the project partners for continued system refinement.

  6. Enablers and Barriers to Large-Scale Uptake of Improved Solid Fuel Stoves: A Systematic Review

    Science.gov (United States)

    Puzzolo, Elisa; Stanistreet, Debbi; Pope, Daniel; Bruce, Nigel G.

    2013-01-01

    Background: Globally, 2.8 billion people rely on household solid fuels. Reducing the resulting adverse health, environmental, and development consequences will involve transitioning through a mix of clean fuels and improved solid fuel stoves (IS) of demonstrable effectiveness. To date, achieving uptake of IS has presented significant challenges. Objectives: We performed a systematic review of factors that enable or limit large-scale uptake of IS in low- and middle-income countries. Methods: We conducted systematic searches through multidisciplinary databases, specialist websites, and consulting experts. The review drew on qualitative, quantitative, and case studies and used standardized methods for screening, data extraction, critical appraisal, and synthesis. We summarized our findings as “factors” relating to one of seven domains—fuel and technology characteristics; household and setting characteristics; knowledge and perceptions; finance, tax, and subsidy aspects; market development; regulation, legislation, and standards; programmatic and policy mechanisms—and also recorded issues that impacted equity. Results: We identified 31 factors influencing uptake from 57 studies conducted in Asia, Africa, and Latin America. All domains matter. Although factors such as offering technologies that meet household needs and save fuel, user training and support, effective financing, and facilitative government action appear to be critical, none guarantee success: All factors can be influential, depending on context. The nature of available evidence did not permit further prioritization. Conclusions: Achieving adoption and sustained use of IS at a large scale requires that all factors, spanning household/community and program/societal levels, be assessed and supported by policy. We propose a planning tool that would aid this process and suggest further research to incorporate an evaluation of effectiveness. Citation: Rehfuess EA, Puzzolo E, Stanistreet D, Pope D, Bruce

  7. Catalyst design for clean and efficient fuels

    DEFF Research Database (Denmark)

    Šaric, Manuel

    cobalt promoted MoS2 catalyst. Reactivity of a series of model molecules, found in oil prior to desulfurization, is studied on cobalt promoted MoS2. Such an approach has the potential to explain the underlying processes involved in the removal of sulfur at each specific site of the catalyst. The goal...... is to identify which sites are active towards specific molecules and in getting insight to what the ideal catalyst should look like in terms of morphology. Dimethyl carbonate is an environmentally benign compound that can be used as a solvent and precursor in chemical synthesis or as a fuel and fuel additive...... processes currently used. It is found that noble metals can be used as electrocatalysts for the synthesis of dimethyl carbonate, significantly lowering the potential when using copper instead of gold. Besides being active, copper was found to be selective towards dimethyl carbonate. A non-selective catalyst...

  8. Strategic research roadmap on ICT-enabled energy efficiency in buildings

    Energy Technology Data Exchange (ETDEWEB)

    Kazi, A.S., Email: sami.kazi@vtt.fi

    2012-06-15

    The REEB Project (The European strategic research Roadmap to ICT-enabled Energy- Efficiency in Buildings and construction projects) was a Coordination Action project funded under the European Commission's Seventh Framework Programme. Its main purpose was to provide a strategic research roadmap on information and communications technology (ICT) support for energy efficiency in the built environment and a collection of implementation actions supporting the realisation of the roadmap. (orig.)

  9. Fuel efficiency, availability and compressor station configuration

    Energy Technology Data Exchange (ETDEWEB)

    Lubomirsky, Matt; Kurz, Rainer [Solar Turbines Inc., San Diego, CA (United States); Klimov, Pavel [Intergas Central Asia, Astana (Kazakhstan)

    2009-12-19

    Compressor stations play a very important role in the success of a gas pipeline design and a careful selection of centrifugal compressors and drivers are key aspects for the success of the project. The state of the art design available today for this equipment provides overall high thermodynamic performance and consequently minimizes installed power requirements and energy usage with significant savings on operating expenses during the economic life of the project For any application of machinery in a pipeline compression station, one of the key questions to answer is the number of units to install to meet the flow requirements of the pipeline. Depending on the load profile of the pipeline, the answers may look different. Other factors to consider include the fact that gas turbines can produce a significant amount of additional power at lower ambient temperatures. So, even for constant load of the pipeline, the relative load of the driver changes. In this paper, a typical transcontinental pipeline with multiple compressor stations is evaluated. The determination of the exact hydraulic behavior of the pipeline is part of the modeling effort. The site ambient conditions, with a significant swing in ambient temperatures are considered. The issue discussed in this paper evolves around the availability that can be achieved with various configurations, based on actually achieved reliability and availability numbers. The other large impact on operating costs, fuel consumption will be discussed. Here, the choice of the number of installed units has a distinct impact on annual fuel consumption, as well as the capacity of the pipeline during various scenarios. (author)

  10. Efficient characterization of fuel depletion in boiling water reactor

    International Nuclear Information System (INIS)

    Kim, S.H.

    1980-01-01

    An efficient fuel depletion method for boiling water reactor (BWR) fuel assemblies has been developed for fuel cycle analysis. A computer program HISTORY based on this method was designed to carry out accurate and rapid fuel burnup calculation for the fuel assembly. It has been usefully employed to study the depletion characteristics of the fuel assemblies for the preparation of nodal code input data and the fuel management study. The adequacy and the effectiveness of the assessment of this method used in HISTORY were demonstrated by comparing HISTORY results with more detailed CASMO results. The computing cost of HISTORY typically has been less than one dollar for the fuel assembly-level depletion calculations over the full life of the assembly, in contrast to more than $1000 for CASMO. By combining CASMO and HISTORY, a large number of expensive CASMO calculations can be replaced by inexpensive HISTORY. For the depletion calculations via CASMO/HISTORY, CASMO calculations are required only for the reference conditions and just at the beginning of life for other cases such as changes in void fraction, control rod condition and temperature. The simple and inexpensive HISTORY is sufficienty accurate and fast to be used in conjunction with CASMO for fuel cycle analysis and some BWR design calculations

  11. Using Email to Enable E[superscript 3] (Effective, Efficient, and Engaging) Learning

    Science.gov (United States)

    Kim, ChanMin

    2008-01-01

    This article argues that technology that supports both noncognitive and cognitive aspects can make learning more effective, efficient, and engaging (e[superscript 3]-learning). The technology of interest in this article is email. The investigation focuses on characteristics of email that are likely to enable e[superscript 3]-learning. In addition,…

  12. A vapor feed methanol microfluidic fuel cell with high fuel and energy efficiency

    International Nuclear Information System (INIS)

    Wang, Yifei; Leung, Dennis Y.C.; Xuan, Jin; Wang, Huizhi

    2015-01-01

    Highlights: • A microfluidic fuel cell with a vapor feed anode is investigated. • Its advantages include simpler design, direct usage of methanol and better performance. • The prototype achieves a peak power density of 55.4 mW cm −2 under room temperature. • The energy efficiency of 9.4% is much higher than its liquid feed counterpart. - Abstract: In this paper, a prototype of methanol microfluidic fuel cell with vapor feed anode configuration is proposed to improve the fuel and energy efficiency of the conventional liquid feed methanol microfluidic fuel cells. Peak power density of 55.4 mW cm −2 can be achieved with this prototype under room temperature, which is 30% higher than its conventional liquid feed counterpart. Moreover, an energy efficiency of 9.4% is achieved, which is 27.5 times higher than its liquid feed counterpart. This superiority on both cell performance and energy efficiency is directly benefitted from its vapor feed anode configuration, which alleviates the fuel crossover, eliminates the fuel depletion boundary layer, and avoids the bulk anolyte wastage. The tradeoff between cell performance and fuel utilization for conventional liquid feed microfluidic fuel cells is also evaded

  13. Efficient Use of Cogeneration and Fuel Diversification

    Directory of Open Access Journals (Sweden)

    Kunickis M.

    2015-12-01

    Full Text Available Energy policy of the European Community is implemented by setting various goals in directives and developing support mechanisms to achieve them. However, very often these policies and legislation come into contradiction with each other, for example Directive 2009/28/EC on the promotion of the use of energy from renewable sources and Directive 2012/27/EU on energy efficiency, repealing Directive 2004/8/EC on the promotion of cogeneration based on a useful heat demand.

  14. C-5M Fuel Efficiency Through MFOQA Data Analysis

    Science.gov (United States)

    2015-03-26

    then contribute to more accurate fuel loading and more efficient fleet fuel usage. Flight Operations Quality Assurance (FOQA) data uses the quick access ...into the ranges in Table 2. Visual Basic ( VBA ) code was written to quickly parse an entire mission (one of the thirty samples) into usable cruise...segments within the Altitude ranges of Table 2. The logic for focusing upon stable cruise flight segments was outlined in Chapter II. The VBA code

  15. Alternative Practices to Improve Surface Fleet Fuel Efficiency

    Science.gov (United States)

    2014-09-01

    through changes in procedures and operational modifications. iENCON uses BBLs/hr (barrels per hour) to evaluate the change in fuel efficiency (Pehlivan...policies and procedures that can be changed to continue the Navy’s efforts in the reduction of fuel consumption. Chapter III addresses drift...and four main engines. In a “full power” lineup all four engines are online. In a “split plant” lineup two engines remain online, one per shaft

  16. Fixing Detroit: how far, how fast, how fuel-efficient

    OpenAIRE

    Kleinbaum, Rob; McManus, Walter

    2009-01-01

    The Automotive Industry Crisis of 2009 is the worst the industry has ever experienced. This paper helps resolve the debate on how much and fast it should change and how it should it respond to demands for increased fuel efficiency. Looking at the actions of successful corporate turnarounds, the lessons are very clear: implement broad, deep, fast change, replace the management team, and transform the culture. We modeled the impacts of different fuel economy standards on profitability and sales...

  17. Fuel efficient stoves for the poorest two billion

    Science.gov (United States)

    Gadgil, Ashok

    2012-03-01

    About 2 billion people cook their daily meals on generally inefficient, polluting, biomass cookstoves. The fuels include twigs and leaves, agricultural waste, animal dung, firewood, and charcoal. Exposure to resulting smoke leads to acute respiratory illness, and cancers, particularly among women cooks, and their infant children near them. Resulting annual mortality estimate is almost 2 million deaths, higher than that from malaria or tuberculosis. There is a large diversity of cooking methods (baking, boiling, long simmers, brazing and roasting), and a diversity of pot shapes and sizes in which the cooking is undertaken. Fuel-efficiency and emissions depend on the tending of the fire (and thermal power), type of fuel, stove characteristics, and fit of the pot to the stove. Thus, no one perfect fuel-efficient low-emitting stove can suit all users. Affordability imposes a further severe constraint on the stove design. For various economic strata within the users, a variety of stove designs may be appropriate and affordable. In some regions, biomass is harvested non-renewably for cooking fuel. There is also increasing evidence that black carbon emitted from stoves is a significant contributor to atmospheric forcing. Thus improved biomass stoves can also help mitigate global climate change. The speaker will describe specific work undertaken to design, develop, test, and disseminate affordable fuel-efficient stoves for internally displaced persons (IDPs) of Darfur, Sudan, where the IDPs face hardship, humiliation, hunger, and risk of sexual assault owing to their dependence on local biomass for cooking their meals.

  18. Efficient Use of Cogeneration and Fuel Diversification

    Science.gov (United States)

    Kunickis, M.; Balodis, M.; Sarma, U.; Cers, A.; Linkevics, O.

    2015-12-01

    Energy policy of the European Community is implemented by setting various goals in directives and developing support mechanisms to achieve them. However, very often these policies and legislation come into contradiction with each other, for example Directive 2009/28/EC on the promotion of the use of energy from renewable sources and Directive 2012/27/EU on energy efficiency, repealing Directive 2004/8/EC on the promotion of cogeneration based on a useful heat demand. In this paper, the authors attempt to assess the potential conflicts between policy political objectives to increase the share of high-efficiency co-generation and renewable energy sources (RES), based on the example of Riga district heating system (DHS). If a new heat source using biomass is built on the right bank of Riga DHS to increase the share of RES, the society could overpay for additional heat production capacities, such as a decrease in the loading of existing generating units, thereby contributing to an inefficient use of existing capacity. As a result, the following negative consequences may arise: 1) a decrease in primary energy savings (PES) from high-efficiency cogeneration in Riga DHS, 2) an increase in greenhouse gas (GHG) emissions in the Baltic region, 3) the worsening security situation of electricity supply in the Latvian power system, 4) an increase in the electricity market price in the Lithuanian and Latvian price areas of Nord Pool power exchange. Within the framework of the research, calculations of PES and GHG emission volumes have been performed for the existing situation and for the situation with heat source, using biomass. The effect of construction of biomass heat source on power capacity balances and Nord Pool electricity prices has been evaluated.

  19. Efficient solar-to-fuels production from a hybrid microbial-water-splitting catalyst system.

    Science.gov (United States)

    Torella, Joseph P; Gagliardi, Christopher J; Chen, Janice S; Bediako, D Kwabena; Colón, Brendan; Way, Jeffery C; Silver, Pamela A; Nocera, Daniel G

    2015-02-24

    Photovoltaic cells have considerable potential to satisfy future renewable-energy needs, but efficient and scalable methods of storing the intermittent electricity they produce are required for the large-scale implementation of solar energy. Current solar-to-fuels storage cycles based on water splitting produce hydrogen and oxygen, which are attractive fuels in principle but confront practical limitations from the current energy infrastructure that is based on liquid fuels. In this work, we report the development of a scalable, integrated bioelectrochemical system in which the bacterium Ralstonia eutropha is used to efficiently convert CO2, along with H2 and O2 produced from water splitting, into biomass and fusel alcohols. Water-splitting catalysis was performed using catalysts that are made of earth-abundant metals and enable low overpotential water splitting. In this integrated setup, equivalent solar-to-biomass yields of up to 3.2% of the thermodynamic maximum exceed that of most terrestrial plants. Moreover, engineering of R. eutropha enabled production of the fusel alcohol isopropanol at up to 216 mg/L, the highest bioelectrochemical fuel yield yet reported by >300%. This work demonstrates that catalysts of biotic and abiotic origin can be interfaced to achieve challenging chemical energy-to-fuels transformations.

  20. Efficient solar-to-fuels production from a hybrid microbial–water-splitting catalyst system

    Science.gov (United States)

    Torella, Joseph P.; Gagliardi, Christopher J.; Chen, Janice S.; Bediako, D. Kwabena; Colón, Brendan; Way, Jeffery C.; Silver, Pamela A.; Nocera, Daniel G.

    2015-01-01

    Photovoltaic cells have considerable potential to satisfy future renewable-energy needs, but efficient and scalable methods of storing the intermittent electricity they produce are required for the large-scale implementation of solar energy. Current solar-to-fuels storage cycles based on water splitting produce hydrogen and oxygen, which are attractive fuels in principle but confront practical limitations from the current energy infrastructure that is based on liquid fuels. In this work, we report the development of a scalable, integrated bioelectrochemical system in which the bacterium Ralstonia eutropha is used to efficiently convert CO2, along with H2 and O2 produced from water splitting, into biomass and fusel alcohols. Water-splitting catalysis was performed using catalysts that are made of earth-abundant metals and enable low overpotential water splitting. In this integrated setup, equivalent solar-to-biomass yields of up to 3.2% of the thermodynamic maximum exceed that of most terrestrial plants. Moreover, engineering of R. eutropha enabled production of the fusel alcohol isopropanol at up to 216 mg/L, the highest bioelectrochemical fuel yield yet reported by >300%. This work demonstrates that catalysts of biotic and abiotic origin can be interfaced to achieve challenging chemical energy-to-fuels transformations. PMID:25675518

  1. Efficiency of poly-generating high temperature fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Margalef, Pere; Brown, Tim; Brouwer, Jacob; Samuelsen, Scott [National Fuel Cell Research Center (NFCRC), University of California, Irvine, CA 92697-3550 (United States)

    2011-02-15

    High temperature fuel cells can be designed and operated to poly-generate electricity, heat, and useful chemicals (e.g., hydrogen) in a variety of configurations. The highly integrated and synergistic nature of poly-generating high temperature fuel cells, however, precludes a simple definition of efficiency for analysis and comparison of performance to traditional methods. There is a need to develop and define a methodology to calculate each of the co-product efficiencies that is useful for comparative analyses. Methodologies for calculating poly-generation efficiencies are defined and discussed. The methodologies are applied to analysis of a Hydrogen Energy Station (H{sub 2}ES) showing that high conversion efficiency can be achieved for poly-generation of electricity and hydrogen. (author)

  2. Improving Energy Efficiency and Enabling Water Recycle in Biorefineries Using Bioelectrochemical Cells

    International Nuclear Information System (INIS)

    Borole, Abhijeet P.

    2010-01-01

    Improving biofuel yield and water reuse are two important issues in further development of biorefineries. The total energy content of liquid fuels (including ethanol and hydrocarbon) produced from cellulosic biomass via biochemical or hybrid bio-thermochemical routes can vary from 49% to 70% of the biomass entering the biorefinery, on an energy basis. Use of boiler for combustion of residual organics and lignin results in significant energy and water losses. An alternate process to improve energy recovery from the residual organic streams is via use of bioelectrochemical systems such as microbial fuel cells (MFCs) microbial electrolysis cells (MECs). The potential advantages of this alternative scheme in a biorefinery include minimization of heat loss and generation of a higher value product, hydrogen. The need for 5-15 gallons of water per gallon of ethanol can be reduced significantly via recycle of water after MEC treatment. Removal of inhibitory byproducts such as furans, phenolics and acetate in MFC/MECs to generate energy, thus, has dual advantages including improvements in energy efficiency and ability to recycle water. Conversion of the sugar- and lignin- degradation products to hydrogen is synergistic with biorefinery hydrogen requirements for upgrading F-T liquids and other byproducts to high-octane fuels and/or high value products. Some of these products include sorbitol, succinic acid, furan and levulinate derivatives, glycols, polyols, 1,4-butenadiol, phenolics polymers, etc. Potential process alternatives utilizing MECs in biorefineries capable of improving energy efficiency by up to 30% are discussed.

  3. The importance of vehicle costs, fuel prices, and fuel efficiency to HEV market success.

    Energy Technology Data Exchange (ETDEWEB)

    Santini, D. J.; Patterson, P. D.; Vyas, A. D.

    1999-12-08

    Toyota's introduction of a hybrid electric vehicle (HEV) named ''Prius'' in Japan and Honda's proposed introduction of an HEV in the United States have generated considerable interest in the long-term viability of such fuel-efficient vehicles. A performance and cost projection model developed entirely at Argonne National Laboratory (ANL) is used here to estimate costs. ANL staff developed fuel economy estimates by extending conventional vehicle (CV) modeling done primarily under the National Cooperative Highway Research Program. Together, these estimates are employed to analyze dollar costs vs. benefits of two of many possible HEV technologies. We project incremental costs and fuel savings for a Prius-type low-performance hybrid (14.3 seconds zero to 60 mph acceleration, 260 time) and a higher-performance ''mild'' hybrid vehicle, or MHV (11 seconds 260 time). Each HEV is compared to a U.S. Toyota Corolla with automatic transmission (11 seconds 260 time). The base incremental retail price range, projected a decade hence, is $3,200-$3,750, before considering battery replacement cost. Historical data are analyzed to evaluate the effect of fuel price on consumer preferences for vehicle fuel economy, performance, and size. The relationship between fuel price, the level of change in fuel price, and consumer attitude toward higher fuel efficiency is also evaluated. A recent survey on the value of higher fuel efficiency is presented and U.S. commercial viability of the hybrids is evaluated using discount rates of 2090 and 870. Our analysis, with our current HEV cost estimates and current fuel savings estimates, implies that the U.S. market for such HEVS would be quite limited.

  4. Emf, maximum power and efficiency of fuel cells

    International Nuclear Information System (INIS)

    Gaggioli, R.A.; Dunbar, W.R.

    1990-01-01

    This paper discusses the ideal voltage of steady-flow fuel cells usually expressed by Emf = -ΔG/nF where ΔG is the Gibbs free energy of reaction for the oxidation of the fuel at the supposed temperature of operation of the cell. Furthermore, the ideal power of the cell is expressed as the product of the fuel flow rate with this emf, and the efficiency of a real fuel cell, sometimes called the Gibbs efficiency, is defined as the ratio of the actual power output to this ideal power. Such viewpoints are flawed in several respects. While it is true that if a cell operates isothermally the maximum conceivable work output is equal to the difference between the Gibbs free energy of the incoming reactants and that of the leaving products, nevertheless, even if the cell operates isothermally, the use of the conventional ΔG of reaction assumes that the products of reaction leave separately from one another (and from any unused fuel), and when ΔS of reaction is positive it assumes that a free heat source exists at the operating temperature, whereas if ΔS is negative it neglects the potential power which theoretically could be obtained form the heat released during oxidation. Moreover, the usual cell does not operate isothermally but (virtually) adiabatically

  5. Enabling LTE and WiFi Coexisting in 5 GHz for Efficient Spectrum Utilization

    Directory of Open Access Journals (Sweden)

    Hongyu Sun

    2017-01-01

    Full Text Available Due to the increasing mobile traffic demands in cellular network, researchers have proposed the coexistence of LTE and WiFi technologies in 5 GHz unlicensed bands. Therefore, how to efficiently utilize the spectrum in 5 GHz becomes extremely important. To avoid the channel access conflicts, current LTE Unlicensed (LTE-U technology introduces the duty cycle of LTE, while License-Assisted Access (LAA technology introduces Listen-Before-Talk (LBT mechanism. While these two technologies improve the spectrum utilization by using time division access schema, we believe that more efficient spectrum utilization can be achieved by enabling simultaneous transmissions from LTE and WiFi. In this paper, we propose a novel method (i.e., Low Amplitude Stream Injection (LASI method to enable the simultaneous transmissions of WiFi and LTE frames in the same channel and recover the data from the conflicts. To further utilize the LASI method, we introduce the Conflict-Tolerant Channel Allocation (CTCA algorithm to optimize the channel allocation and achieve more efficient spectrum utilization in 5 GHz. Extensive simulation results show that our approach achieves lower latency and higher throughput. Compared with the state-of-the-art LTE-U and LAA technologies, our approach can improve the spectrum efficiency 2.9 times.

  6. Effect of proton-conduction in electrolyte on electric efficiency of multi-stage solid oxide fuel cells

    Science.gov (United States)

    Matsuzaki, Yoshio; Tachikawa, Yuya; Somekawa, Takaaki; Hatae, Toru; Matsumoto, Hiroshige; Taniguchi, Shunsuke; Sasaki, Kazunari

    2015-07-01

    Solid oxide fuel cells (SOFCs) are promising electrochemical devices that enable the highest fuel-to-electricity conversion efficiencies under high operating temperatures. The concept of multi-stage electrochemical oxidation using SOFCs has been proposed and studied over the past several decades for further improving the electrical efficiency. However, the improvement is limited by fuel dilution downstream of the fuel flow. Therefore, evolved technologies are required to achieve considerably higher electrical efficiencies. Here we present an innovative concept for a critically-high fuel-to-electricity conversion efficiency of up to 85% based on the lower heating value (LHV), in which a high-temperature multi-stage electrochemical oxidation is combined with a proton-conducting solid electrolyte. Switching a solid electrolyte material from a conventional oxide-ion conducting material to a proton-conducting material under the high-temperature multi-stage electrochemical oxidation mechanism has proven to be highly advantageous for the electrical efficiency. The DC efficiency of 85% (LHV) corresponds to a net AC efficiency of approximately 76% (LHV), where the net AC efficiency refers to the transmission-end AC efficiency. This evolved concept will yield a considerably higher efficiency with a much smaller generation capacity than the state-of-the-art several tens-of-MW-class most advanced combined cycle (MACC).

  7. Factors influencing efficient structure of fuel and energy complex

    Science.gov (United States)

    Sidorova, N. G.; Novikova, S. A.

    2017-10-01

    The development of the Russian fuel-energy complex is a priority for the national economic policy, and the Far East is a link between Russia and the Asia-Pacific region. Large-scale engineering of numerous resources of the Far East will force industrial development, increase living standard and strengthen Russia’s position in the global energy market. So, revealing the factors which influence rational structure of the fuel-energy complex is very urgent nowadays. With the use of depth analysis of development tendencies of the complex and its problems the authors show ways of its efficiency improvement.

  8. Gasoline Ultra Efficient Fuel Vehicle with Advanced Low Temperature Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Confer, Keith [Delphi Automotive Systems, LLC, Troy, MI (United States)

    2014-12-18

    The objective of this program was to develop, implement and demonstrate fuel consumption reduction technologies which are focused on reduction of friction and parasitic losses and on the improvement of thermal efficiency from in-cylinder combustion. The program was executed in two phases. The conclusion of each phase was marked by an on-vehicle technology demonstration. Phase I concentrated on short term goals to achieve technologies to reduce friction and parasitic losses. The duration of Phase I was approximately two years and the target fuel economy improvement over the baseline was 20% for the Phase I demonstration. Phase II was focused on the development and demonstration of a breakthrough low temperature combustion process called Gasoline Direct- Injection Compression Ignition (GDCI). The duration of Phase II was approximately four years and the targeted fuel economy improvement was 35% over the baseline for the Phase II demonstration vehicle. The targeted tailpipe emissions for this demonstration were Tier 2 Bin 2 emissions standards.

  9. Polymer Separators for High-Power, High-Efficiency Microbial Fuel Cells

    KAUST Repository

    Chen, Guang

    2012-12-26

    Microbial fuel cells (MFCs) with hydrophilic poly(vinyl alcohol) (PVA) separators showed higher Coulombic efficiencies (94%) and power densities (1220 mW m-2) than cells with porous glass fiber separators or reactors without a separator after 32 days of operation. These remarkable increases in both the coublomic efficiency and the power production of the microbial fuel cells were made possible by the separator\\'s unique characteristics of fouling mitigation of the air cathode without a large increase in ionic resistance in the cell. This new type of polymer gel-like separator design will be useful for improving MFC reactor performance by enabling compact cell designs. © 2012 American Chemical Society.

  10. Efficiency of Polymer Electrolyte Membrane Fuel Cell Stack

    Directory of Open Access Journals (Sweden)

    Hans Bosma

    2011-08-01

    Full Text Available This paper applies a feedforward control of optimal oxygen excess ratio that maximize net power (improve efficiency of a NedStack P8.0-64 PEM fuel cell stack (FCS system. Net powers profile as a function of oxygen excess ratio for some points of operation are analyzed by using FCS model. The relationships between stack current and the corresponding control input voltage that gives an optimal oxygen excess ratio are used to design a feedforward control scheme. The results of this scheme are compared to the results of a feedforward control using a constant oxygen excess ratio. Simulation results show that optimal oxygen excess ratio improves fuel cell performance compared to the results of constant oxygen excess ratio. The same procedures are performed experimentally for the FCS system. The behaviour of the net power of the fuel cell stack with respect to the variation of oxygen excess ratio is analyzed to obtain optimal values. Data of stack current and the corresponding voltage input to the compressor that gives optimal values of oxygen excess ratio are used to develop a feedforward control. Feedforward control based on constant and optimal oxygen excess ratio control, are implemented in the NedStack P8.0-64 PEM fuel cell stack system by using LabVIEW. Implementation results shows that optimal oxygen excess ratio control improves the fuel cell performance compared to the constant oxygen excess ratio control.

  11. A Nonfullerene Small Molecule Acceptor with 3D Interlocking Geometry Enabling Efficient Organic Solar Cells.

    Science.gov (United States)

    Lee, Jaewon; Singh, Ranbir; Sin, Dong Hun; Kim, Heung Gyu; Song, Kyu Chan; Cho, Kilwon

    2016-01-06

    A new 3D nonfullerene small-molecule acceptor is reported. The 3D interlocking geometry of the small-molecule acceptor enables uniform molecular conformation and strong intermolecular connectivity, facilitating favorable nanoscale phase separation and electron charge transfer. By employing both a novel polymer donor and a nonfullerene small-molecule acceptor in the solution-processed organic solar cells, a high-power conversion efficiency of close to 6% is demonstrated. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Pathways to Commercial Success: Technologies and Innovations Enabled by the U.S. Department of Energy Fuel Cell Technologies Office

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2017-10-11

    This report published in October 2017 updates the results of an effort to identify and document the commercial and emerging (projected to be commercialized within the next 3 to 5 years) hydrogen and fuel cell technologies and products that resulted from U.S. Department of Energy support through the Fuel Cell Technologies Office in the Office of Energy Efficiency and Renewable Energy.

  13. HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS USING NUCLEAR POWER

    Energy Technology Data Exchange (ETDEWEB)

    BROWN,LC; BESENBRUCH,GE; LENTSCH,RD; SCHULTZ,KR; FUNK,JF; PICKARD,PS; MARSHALL,AC; SHOWALTER,SK

    2003-06-01

    OAK B202 HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS USING NUCLEAR POWER. Combustion of fossil fuels, used to power transportation, generate electricity, heat homes and fuel industry provides 86% of the world's energy. Drawbacks to fossil fuel utilization include limited supply, pollution, and carbon dioxide emissions. Carbon dioxide emissions, thought to be responsible for global warming, are now the subject of international treaties. Together, these drawbacks argue for the replacement of fossil fuels with a less-polluting potentially renewable primary energy such as nuclear energy. Conventional nuclear plants readily generate electric power but fossil fuels are firmly entrenched in the transportation sector. Hydrogen is an environmentally attractive transportation fuel that has the potential to displace fossil fuels. Hydrogen will be particularly advantageous when coupled with fuel cells. Fuel cells have higher efficiency than conventional battery/internal combustion engine combinations and do not produce nitrogen oxides during low-temperature operation. Contemporary hydrogen production is primarily based on fossil fuels and most specifically on natural gas. When hydrogen is produced using energy derived from fossil fuels, there is little or no environmental advantage. There is currently no large scale, cost-effective, environmentally attractive hydrogen production process available for commercialization, nor has such a process been identified. The objective of this work is to find an economically feasible process for the production of hydrogen, by nuclear means, using an advanced high-temperature nuclear reactor as the primary energy source. Hydrogen production by thermochemical water-splitting (Appendix A), a chemical process that accomplishes the decomposition of water into hydrogen and oxygen using only heat or, in the case of a hybrid thermochemical process, by a combination of heat and electrolysis, could meet these goals. Hydrogen produced from

  14. Lean Gasoline System Development for Fuel Efficient Small Cars

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Stuart R. [General Motors LLC, Pontiac, MI (United States)

    2013-11-25

    The General Motors and DOE cooperative agreement program DE-EE0003379 is completed. The program has integrated and demonstrated a lean-stratified gasoline engine, a lean aftertreatment system, a 12V Stop/Start system and an Active Thermal Management system along with the necessary controls that significantly improves fuel efficiency for small cars. The fuel economy objective of an increase of 25% over a 2010 Chevrolet Malibu and the emission objective of EPA T2B2 compliance have been accomplished. A brief review of the program, summarized from the narrative is: The program accelerates development and synergistic integration of four cost competitive technologies to improve fuel economy of a light-duty vehicle by at least 25% while meeting Tier 2 Bin 2 emissions standards. These technologies can be broadly implemented across the U.S. light-duty vehicle product line between 2015 and 2025 and are compatible with future and renewable biofuels. The technologies in this program are: lean combustion, innovative passive selective catalyst reduction lean aftertreatment, 12V stop/start and active thermal management. The technologies will be calibrated in a 2010 Chevrolet Malibu mid-size sedan for final fuel economy demonstration.

  15. 41 CFR 109-40.303-3 - Most fuel efficient carrier/mode.

    Science.gov (United States)

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Most fuel efficient...-3 Most fuel efficient carrier/mode. When more than one mode, or more than one carrier within a mode... cost, the carrier/mode determined to be the most fuel efficient will be selected. In determining the...

  16. Integration of direct carbon and hydrogen fuel cells for highly efficient power generation from hydrocarbon fuels

    Energy Technology Data Exchange (ETDEWEB)

    Muradov, Nazim; Choi, Pyoungho; Smith, Franklyn; Bokerman, Gary [Florida Solar Energy Center, University of Central Florida, 1679 Clearlake Road, Cocoa, FL 32922-5703 (United States)

    2010-02-15

    In view of impending depletion of hydrocarbon fuel resources and their negative environmental impact, it is imperative to significantly increase the energy conversion efficiency of hydrocarbon-based power generation systems. The combination of a hydrocarbon decomposition reactor with a direct carbon and hydrogen fuel cells (FC) as a means for a significant increase in chemical-to-electrical energy conversion efficiency is discussed in this paper. The data on development and operation of a thermocatalytic hydrocarbon decomposition reactor and its coupling with a proton exchange membrane FC are presented. The analysis of the integrated power generating system including a hydrocarbon decomposition reactor, direct carbon and hydrogen FC using natural gas and propane as fuels is conducted. It was estimated that overall chemical-to-electrical energy conversion efficiency of the integrated system varied in the range of 49.4-82.5%, depending on the type of fuel and FC used, and CO{sub 2} emission per kW{sub el}h produced is less than half of that from conventional power generation sources. (author)

  17. Enabling online studies of conceptual relationships between medical terms: developing an efficient web platform.

    Science.gov (United States)

    Albin, Aaron; Ji, Xiaonan; Borlawsky, Tara B; Ye, Zhan; Lin, Simon; Payne, Philip Ro; Huang, Kun; Xiang, Yang

    2014-10-07

    The Unified Medical Language System (UMLS) contains many important ontologies in which terms are connected by semantic relations. For many studies on the relationships between biomedical concepts, the use of transitively associated information from ontologies and the UMLS has been shown to be effective. Although there are a few tools and methods available for extracting transitive relationships from the UMLS, they usually have major restrictions on the length of transitive relations or on the number of data sources. Our goal was to design an efficient online platform that enables efficient studies on the conceptual relationships between any medical terms. To overcome the restrictions of available methods and to facilitate studies on the conceptual relationships between medical terms, we developed a Web platform, onGrid, that supports efficient transitive queries and conceptual relationship studies using the UMLS. This framework uses the latest technique in converting natural language queries into UMLS concepts, performs efficient transitive queries, and visualizes the result paths. It also dynamically builds a relationship matrix for two sets of input biomedical terms. We are thus able to perform effective studies on conceptual relationships between medical terms based on their relationship matrix. The advantage of onGrid is that it can be applied to study any two sets of biomedical concept relations and the relations within one set of biomedical concepts. We use onGrid to study the disease-disease relationships in the Online Mendelian Inheritance in Man (OMIM). By crossvalidating our results with an external database, the Comparative Toxicogenomics Database (CTD), we demonstrated that onGrid is effective for the study of conceptual relationships between medical terms. onGrid is an efficient tool for querying the UMLS for transitive relations, studying the relationship between medical terms, and generating hypotheses.

  18. Corrugation Architecture Enabled Ultraflexible Wafer-Scale High-Efficiency Monocrystalline Silicon Solar Cell

    KAUST Repository

    Bahabry, Rabab R.

    2018-01-02

    Advanced classes of modern application require new generation of versatile solar cells showcasing extreme mechanical resilience, large-scale, low cost, and excellent power conversion efficiency. Conventional crystalline silicon-based solar cells offer one of the most highly efficient power sources, but a key challenge remains to attain mechanical resilience while preserving electrical performance. A complementary metal oxide semiconductor-based integration strategy where corrugation architecture enables ultraflexible and low-cost solar cell modules from bulk monocrystalline large-scale (127 × 127 cm) silicon solar wafers with a 17% power conversion efficiency. This periodic corrugated array benefits from an interchangeable solar cell segmentation scheme which preserves the active silicon thickness of 240 μm and achieves flexibility via interdigitated back contacts. These cells can reversibly withstand high mechanical stress and can be deformed to zigzag and bifacial modules. These corrugation silicon-based solar cells offer ultraflexibility with high stability over 1000 bending cycles including convex and concave bending to broaden the application spectrum. Finally, the smallest bending radius of curvature lower than 140 μm of the back contacts is shown that carries the solar cells segments.

  19. Corrugation Architecture Enabled Ultraflexible Wafer-Scale High-Efficiency Monocrystalline Silicon Solar Cell

    KAUST Repository

    Bahabry, Rabab R.; Kutbee, Arwa T.; Khan, Sherjeel M.; Sepulveda, Adrian C.; Wicaksono, Irmandy; Nour, Maha A.; Wehbe, Nimer; Almislem, Amani Saleh Saad; Ghoneim, Mohamed T.; Sevilla, Galo T.; Syed, Ahad; Shaikh, Sohail F.; Hussain, Muhammad Mustafa

    2018-01-01

    Advanced classes of modern application require new generation of versatile solar cells showcasing extreme mechanical resilience, large-scale, low cost, and excellent power conversion efficiency. Conventional crystalline silicon-based solar cells offer one of the most highly efficient power sources, but a key challenge remains to attain mechanical resilience while preserving electrical performance. A complementary metal oxide semiconductor-based integration strategy where corrugation architecture enables ultraflexible and low-cost solar cell modules from bulk monocrystalline large-scale (127 × 127 cm) silicon solar wafers with a 17% power conversion efficiency. This periodic corrugated array benefits from an interchangeable solar cell segmentation scheme which preserves the active silicon thickness of 240 μm and achieves flexibility via interdigitated back contacts. These cells can reversibly withstand high mechanical stress and can be deformed to zigzag and bifacial modules. These corrugation silicon-based solar cells offer ultraflexibility with high stability over 1000 bending cycles including convex and concave bending to broaden the application spectrum. Finally, the smallest bending radius of curvature lower than 140 μm of the back contacts is shown that carries the solar cells segments.

  20. Advanced proton-exchange materials for energy efficient fuel cells.

    Energy Technology Data Exchange (ETDEWEB)

    Fujimoto, Cy H.; Grest, Gary Stephen; Hickner, Michael A.; Cornelius, Christopher James; Staiger, Chad Lynn; Hibbs, Michael R.

    2005-12-01

    The ''Advanced Proton-Exchange Materials for Energy Efficient Fuel Cells'' Laboratory Directed Research and Development (LDRD) project began in October 2002 and ended in September 2005. This LDRD was funded by the Energy Efficiency and Renewable Energy strategic business unit. The purpose of this LDRD was to initiate the fundamental research necessary for the development of a novel proton-exchange membranes (PEM) to overcome the material and performance limitations of the ''state of the art'' Nafion that is used in both hydrogen and methanol fuel cells. An atomistic modeling effort was added to this LDRD in order to establish a frame work between predicted morphology and observed PEM morphology in order to relate it to fuel cell performance. Significant progress was made in the area of PEM material design, development, and demonstration during this LDRD. A fundamental understanding involving the role of the structure of the PEM material as a function of sulfonic acid content, polymer topology, chemical composition, molecular weight, and electrode electrolyte ink development was demonstrated during this LDRD. PEM materials based upon random and block polyimides, polybenzimidazoles, and polyphenylenes were created and evaluated for improvements in proton conductivity, reduced swelling, reduced O{sub 2} and H{sub 2} permeability, and increased thermal stability. Results from this work reveal that the family of polyphenylenes potentially solves several technical challenges associated with obtaining a high temperature PEM membrane. Fuel cell relevant properties such as high proton conductivity (>120 mS/cm), good thermal stability, and mechanical robustness were demonstrated during this LDRD. This report summarizes the technical accomplishments and results of this LDRD.

  1. Can Differentiated Production Planning and Control enable both Responsiveness and Efficiency in Food Production?

    Directory of Open Access Journals (Sweden)

    Anita Romsdal

    2014-07-01

    Full Text Available This paper addresses the complex production planning and control (PPC challenges in food supply chains. The study illustrates how food producers' traditional make‐to‐stock (MTS approach is not well suited to meet the trends of increasing product variety, higher demand uncertainty, increasing sales of fresh food products and more demanding customers. The paper proposes a framework for differentiated PPC that combines MTS with make‐to‐order (MTO.The framework matches products with the most appropriate PPC approaches and buffering techniques depending on market and product characteristics. The core idea is to achieve more volume flexibility in the production system by exploiting favourable product and market characteristics (high demand predictability, long customer order leadtime allowances and low product perishability. A case study is used to demonstrate how the framework can enable food producers to achieve efficiency in production, inventory and PPC processes – and simultaneously be responsive to market requirements.

  2. Energy Efficient, Cross-Layer Enabled, Dynamic Aggregation Networks for Next Generation Internet

    Science.gov (United States)

    Wang, Michael S.

    Today, the Internet traffic is growing at a near exponential rate, driven predominately by data center-based applications and Internet-of-Things services. This fast-paced growth in Internet traffic calls into question the ability of the existing optical network infrastructure to support this continued growth. The overall optical networking equipment efficiency has not been able to keep up with the traffic growth, creating a energy gap that makes energy and cost expenditures scale linearly with the traffic growth. The implication of this energy gap is that it is infeasible to continue using existing networking equipment to meet the growing bandwidth demand. A redesign of the optical networking platform is needed. The focus of this dissertation is on the design and implementation of energy efficient, cross-layer enabled, dynamic optical networking platforms, which is a promising approach to address the exponentially growing Internet bandwidth demand. Chapter 1 explains the motivation for this work by detailing the huge Internet traffic growth and the unsustainable energy growth of today's networking equipment. Chapter 2 describes the challenges and objectives of enabling agile, dynamic optical networking platforms and the vision of the Center for Integrated Access Networks (CIAN) to realize these objectives; the research objectives of this dissertation and the large body of related work in this field is also summarized. Chapter 3 details the design and implementation of dynamic networking platforms that support wavelength switching granularity. The main contribution of this work involves the experimental validation of deep cross-layer communication across the optical performance monitoring (OPM), data, and control planes. The first experiment shows QoS-aware video streaming over a metro-scale test-bed through optical power monitoring of the transmission wavelength and cross-layer feedback control of the power level. The second experiment extends the performance

  3. Enabling MPEG-2 video playback in embedded systems through improved data cache efficiency

    Science.gov (United States)

    Soderquist, Peter; Leeser, Miriam E.

    1999-01-01

    Digital video decoding, enabled by the MPEG-2 Video standard, is an important future application for embedded systems, particularly PDAs and other information appliances. Many such system require portability and wireless communication capabilities, and thus face severe limitations in size and power consumption. This places a premium on integration and efficiency, and favors software solutions for video functionality over specialized hardware. The processors in most embedded system currently lack the computational power needed to perform video decoding, but a related and equally important problem is the required data bandwidth, and the need to cost-effectively insure adequate data supply. MPEG data sets are very large, and generate significant amounts of excess memory traffic for standard data caches, up to 100 times the amount required for decoding. Meanwhile, cost and power limitations restrict cache sizes in embedded systems. Some systems, including many media processors, eliminate caches in favor of memories under direct, painstaking software control in the manner of digital signal processors. Yet MPEG data has locality which caches can exploit if properly optimized, providing fast, flexible, and automatic data supply. We propose a set of enhancements which target the specific needs of the heterogeneous types within the MPEG decoder working set. These optimizations significantly improve the efficiency of small caches, reducing cache-memory traffic by almost 70 percent, and can make an enhanced 4 KB cache perform better than a standard 1 MB cache. This performance improvement can enable high-resolution, full frame rate video playback in cheaper, smaller system than woudl otherwise be possible.

  4. Increasing efficiency of TPP fuel suply system due to LNG usage as a reserve fuel

    Science.gov (United States)

    Zhigulina, E. V.; Khromchenkov, V. G.; Mischner, J.; Yavorovsky, Y. V.

    2017-11-01

    The paper is devoted to the analysis of fuel economy efficiency increase possibility at thermal power plants (TPP) due to the transition from the use of black oil as a reserve fuel to liquefied natural gas (LNG) produced at the very station. The work represents the technical solution that allows to generate, to store and to use LNG as the reserve fuel TPP. The annual amounts of black oil and natural gas that are needed to ensure the reliable operation of several power plants in Russia were assessed. Some original schemes of the liquefied natural gas production and storing as alternative reserve fuel generated by means of application of expansion turbines are proposed. The simulation results of the expansion process for two compositions of natural gas with different contents of high-boiling fractions are presented. The dependences of the condensation outlet and power generation from the flow initial parameters and from the natural gas composition are obtained and analysed. It was shown that the choice of a particular circuit design depends primarily on the specific natural gas composition. The calculations have proved the effectiveness and the technical ability to use liquefied natural gas as a backup fuel at reconstructed and newly designed gas power station.

  5. PEAC: A Power-Efficient Adaptive Computing Technology for Enabling Swarm of Small Spacecraft and Deployable Mini-Payloads

    Data.gov (United States)

    National Aeronautics and Space Administration — This task is to develop and demonstrate a path-to-flight and power-adaptive avionics technology PEAC (Power Efficient Adaptive Computing). PEAC will enable emerging...

  6. Enabling factors for the improvement of nitride-based LED efficiency

    International Nuclear Information System (INIS)

    Laubsch, Ansgar; Bergbauer, Werner; Sabathil, Matthias; Peter, Matthias; Meyer, Tobias; Bruederl, Georg; Linder, Norbert; Streubel, Klaus; Oberschmid, Raimund; Hahn, Berthold; Wagner, Joachim

    2008-01-01

    Recent progress in the epitaxial growth of LEDs with InGaN/GaN quantum-well heterostructures has led to a significant enhancement of output power. In this talk, we will discuss the mechanisms limiting the devices' internal efficiency and identify enabling factors for further improvements. We compare samples with different Indium content as well as different design of the active layer. Although heteroepitaxial growth of GaN on sapphire generates high defect densities, non-radiative defect-related Shockley-Read-Hall recombination does not seem to substantially limit the efficiency of standard InGaN/GaN LED structures. We rather discuss a supplemental Auger-like non-radiative path for carrier recombination that becomes dominant at quantum-well carrier densities typical for LED operation. Additionally, the piezo-field induced reduced overlap of electron and hole wavefunction in standard c-plane grown InGaN quantum wells reduces the radiative recombination rate

  7. Combined DECS Analysis and Next-Generation Sequencing Enable Efficient Detection of Novel Plant RNA Viruses

    Directory of Open Access Journals (Sweden)

    Hironobu Yanagisawa

    2016-03-01

    Full Text Available The presence of high molecular weight double-stranded RNA (dsRNA within plant cells is an indicator of infection with RNA viruses as these possess genomic or replicative dsRNA. DECS (dsRNA isolation, exhaustive amplification, cloning, and sequencing analysis has been shown to be capable of detecting unknown viruses. We postulated that a combination of DECS analysis and next-generation sequencing (NGS would improve detection efficiency and usability of the technique. Here, we describe a model case in which we efficiently detected the presumed genome sequence of Blueberry shoestring virus (BSSV, a member of the genus Sobemovirus, which has not so far been reported. dsRNAs were isolated from BSSV-infected blueberry plants using the dsRNA-binding protein, reverse-transcribed, amplified, and sequenced using NGS. A contig of 4,020 nucleotides (nt that shared similarities with sequences from other Sobemovirus species was obtained as a candidate of the BSSV genomic sequence. Reverse transcription (RT-PCR primer sets based on sequences from this contig enabled the detection of BSSV in all BSSV-infected plants tested but not in healthy controls. A recombinant protein encoded by the putative coat protein gene was bound by the BSSV-antibody, indicating that the candidate sequence was that of BSSV itself. Our results suggest that a combination of DECS analysis and NGS, designated here as “DECS-C,” is a powerful method for detecting novel plant viruses.

  8. Commercially Available Activated Carbon Fiber Felt Enables Efficient Solar Steam Generation.

    Science.gov (United States)

    Li, Haoran; He, Yurong; Hu, Yanwei; Wang, Xinzhi

    2018-03-21

    Sun-driven steam generation is now possible and has the potential to help meet future energy needs. Current technologies often use solar condensers to increase solar irradiance. More recently, a technology for solar steam generation that uses heated surface water and low optical concentration is reported. In this work, a commercially available activated carbon fiber felt is used to generate steam efficiently under one sun illumination. The evaporation rate and solar conversion efficiency reach 1.22 kg m -2 h -1 and 79.4%, respectively. The local temperature of the evaporator with a floating activated carbon fiber felt reaches 48 °C. Apart from the high absorptivity (about 94%) of the material, the evaporation performance is enhanced thanks to the well-developed pores for improved water supply and steam escape and the low thermal conductivity, which enables reduced bulk water temperature increase. This study helps to find a promising material for solar steam generation using a water evaporator that can be produced economically (∼6 $/m 2 ) with long-term stability.

  9. Self-Condensation Culture Enables Vascularization of Tissue Fragments for Efficient Therapeutic Transplantation

    Directory of Open Access Journals (Sweden)

    Yoshinobu Takahashi

    2018-05-01

    Full Text Available Summary: Clinical transplantation of tissue fragments, including islets, faces a critical challenge because of a lack of effective strategies that ensure efficient engraftment through the timely integration of vascular networks. We recently developed a complex organoid engineering method by “self-condensation” culture based on mesenchymal cell-dependent contraction, thereby enabling dissociated heterotypic lineages including endothelial cells to self-organize in a spatiotemporal manner. Here, we report the successful adaptation of this method for generating complex tissues from diverse tissue fragments derived from various organs, including pancreatic islets. The self-condensation of human and mouse islets with endothelial cells not only promoted functionalization in culture but also massively improved post-transplant engraftment. Therapeutically, fulminant diabetic mice were more efficiently treated by a vascularized islet transplant compared with the conventional approach. Given the general limitations of post-transplant vascularization associated with 3D tissue-based therapy, our approach offers a promising means of enhancing efficacy in the context of therapeutic tissue transplantation. : Takahashi et al. report on generating vascularized islet tissue from humans and mice. After transplantation, vascularized islets significantly improve survival of diabetic mice, demonstrating the quick normalization of blood glucose compared with conventional islet transplantation. Keywords: tissue engineering, tissue-based therapy, vascularization, islet transplantation, organoid

  10. Efficient regeneration of partially spent ammonia borane fuel

    International Nuclear Information System (INIS)

    Davis, Benjamin Lee; Gordon, John C.; Stephens, Frances; Dixon, David A.; Matus, Myrna H.

    2008-01-01

    A necessary target in realizing a hydrogen (H 2 ) economy, especially for the transportation sector, is its storage for controlled delivery, presumably to an energy producing fuel cell. In this vein, the U.S. Department of Energy's (DOE) Centers of Excellence (CoE) in Hydrogen Storage have pursued different methodologies, including metal hydrides, chemical hydrides, and sorbents, for the expressed purpose of supplanting gasoline's current > 300 mile driving range. Chemical hydrogen storage has been dominated by one appealing material, ammonia borane (H 3 B-NH 3 , AB), due to its high gravimetric capacity of hydrogen (19.6 wt %) and low molecular weight (30.7 g mol -1 ). In addition, AB has both hydridic and protic moieties, yielding a material from which H2 can be readily released. As such, a number of publications have described H 2 release from amine boranes, yielding various rates depending on the method applied. Even though the viability of any chemical hydrogen storage system is critically dependent on efficient recyclability, reports on the latter subject are sparse, invoke the use of high energy reducing agents, and suffer from low yields. For example, the DOE recently decided to no longer pursue the use of NaBH 4 as a H 2 storage material, in part because of inefficient regeneration. We thus endeavored to find an energy efficient regeneration process for the spent fuel from H 2 depleted AB with a minimum number of steps.

  11. Krakow clean fossil fuels and energy efficiency project

    Energy Technology Data Exchange (ETDEWEB)

    Butcher, T.A.; Pierce, B.L. [Brookhaven National Lab., Upton, NY (United States)

    1995-11-01

    The Support for Eastern European Democracy (SEED) Act of 1989 directed the U.S. Department of Energy (DOE) to undertake an equipment assessment project aimed at developing the capability within Poland to manufacture or modify industrial-scale combustion equipment to utilize fossil fuels cleanly. This project is being implemented in the city of Krakow as the `Krakow Clean Fossil Fuels and Energy Efficiency Project.` Funding is provided through the U.S. Agency for International Development (AID). The project is being conducted in a manner that can be generalized to all of Poland and to the rest of Eastern Europe. The historic city of Krakow has a population of 750,000. Almost half of the heating energy used in Krakow is supplied by low-efficiency boilerhouses and home coal stoves. Within the town, there are more than 1,300 local boilerhouses and 100,000 home stoves. These are collectively referred to as the `low emission sources` and they are the primary sources of particulates and hydrocarbon emissions in the city and major contributors of sulfur dioxide and carbon monoxide.

  12. High-efficiency near-infrared enabled planar perovskite solar cells by embedding upconversion nanocrystals.

    Science.gov (United States)

    Meng, Fan-Li; Wu, Jiao-Jiao; Zhao, Er-Fei; Zheng, Yan-Zhen; Huang, Mei-Lan; Dai, Li-Ming; Tao, Xia; Chen, Jian-Feng

    2017-11-30

    Integration of the upconversion effect in perovskite solar cells (PSCs) is a facile approach towards extending the spectral absorption from the visible to the near infrared (NIR) range and reducing the non-absorption loss of solar photons. However, the big challenge for practical application of UCNCs in planar PSCs is the poor compatibility between UCNCs and the perovskite precursor. Herein, we have subtly overcome the tough compatibility issue using a ligand-exchange strategy. For the first time, β-NaYF 4 :Yb,Er UCNCs have been embedded in situ into a CH 3 NH 3 PbI 3 layer to fabricate NIR-enabled planar PSCs. The CH 3 NH 3 I-capped UCNCs generated from the ligand-exchange were mixed with the perovskite precursor and served as nucleation sites for the UCNC-mediated heteroepitaxial growth of perovskite; moreover, the in situ embedding of UCNCs into the perovskite layer was realized during a spin-coating process. The resulting UCNC-embedded perovskite layer attained a uniform pinhole-free morphology with enlarged crystal grains and enabled NIR absorption. It also contributed to the energy transfer from the UCNCs to the perovskite and electron transport to the collecting electrode surface. The device fabricated using the UCNC-embedded perovskite film achieved an average power-conversion efficiency of 18.60% (19.70% for the best) under AM 1.5G and 0.37% under 980 nm laser, corresponding to 54% and 740-fold increase as compared to that of its counterpart without UCNCs.

  13. To Estimation of Efficient Usage of Organic Fuel in the Cycle of Steam Power Installations

    Directory of Open Access Journals (Sweden)

    A. P. Nesenchuk

    2013-01-01

    Full Text Available Tendencies of power engineering development in the world were shown in this article. There were carried out the thermodynamic Analysis of efficient usage of different types of fuel. This article shows the obtained result, which reflects that low-calorie fuel (from the point of thermodynamics is more efficient to use at steam power stations then high-energy fuel.

  14. Clean fuels for resource-poor settings: A systematic review of barriers and enablers to adoption and sustained use.

    Science.gov (United States)

    Puzzolo, Elisa; Pope, Daniel; Stanistreet, Debbi; Rehfuess, Eva A; Bruce, Nigel G

    2016-04-01

    Access to, and sustained adoption of, clean household fuels at scale remains an aspirational goal to achieve sufficient reductions in household air pollution (HAP) in order to impact on the substantial global health burden caused by reliance on solid fuels. To systematically appraise the current evidence base to identify: (i) which factors enable or limit adoption and sustained use of clean fuels (namely liquefied petroleum gas (LPG), biogas, solar cooking and alcohol fuels) in low- and middle-income countries; (ii) lessons learnt concerning equitable scaling-up of programmes of cleaner cooking fuels in relation to poverty, urban-rural settings and gender. A mixed-methods systematic review was conducted using established review methodology and extensive searches of published and grey literature sources. Data extraction and quality appraisal of quantitative, qualitative and case studies meeting inclusion criteria were conducted using standardised methods with reliability checking. Forty-four studies from Africa, Asia and Latin America met the inclusion criteria (17 on biogas, 12 on LPG, 9 on solar, 6 on alcohol fuels). A broad range of inter-related enabling and limiting factors were identified for all four types of intervention, operating across seven pre-specified domains (i.e. fuel and technology characteristics, household and setting characteristics, knowledge and perceptions, financial, tax and subsidy aspects, market development, regulation, legislation and standards, and programme and policy mechanisms) and multiple levels (i.e. household, community, national). All domains matter and the majority of factors are common to all clean fuels interventions reviewed although some are fuel and technology-specific. All factors should therefore be taken into account and carefully assessed during planning and implementation of any small- and large-scale initiative aiming at promoting clean fuels for household cooking. Despite limitations in quantity and quality of the

  15. Trimodal Mixed Mode Chromatography That Enables Efficient Offline Two-Dimensional Peptide Fractionation for Proteome Analysis.

    Science.gov (United States)

    Yu, Peng; Petzoldt, Svenja; Wilhelm, Mathias; Zolg, Daniel Paul; Zheng, Runsheng; Sun, Xuefei; Liu, Xiaodong; Schneider, Günter; Huhmer, Andreas; Kuster, Bernhard

    2017-09-05

    Offline two-dimensional chromatography is a common means to achieve deep proteome coverage. To reduce sample complexity and dynamic range and to utilize mass spectrometer (MS) time efficiently, high chromatographic resolution of and good orthogonality between the two dimensions are needed. Ion exchange and high pH reversed phase chromatography are often used for this purpose. However, the former requires desalting to be MS-compatible, and the latter requires fraction pooling to create orthogonality. Here, we report an alternative first-dimension separation technique using a commercial trimodal phase incorporating polar embedded reversed phase, weak anion exchange, and strong cation exchange material. The column is capable of retaining polar and nonpolar peptides alike without noticeable breakthrough. It allows separating ordinary and TMT-labeled peptides under mild acidic conditions using an acetonitrile gradient. The direct MS compatibility of solvents and good orthogonality to online coupled C18 columns enable a straightforward workflow without fraction pooling and desalting while showing comparable performance to the other techniques. The method scales from low to high microgram sample quantity and is amenable to full automation. To demonstrate practical utility, we analyzed the proteomes of 10 human pancreatic cancer cell lines to a depth of >8,700 quantified proteins.

  16. High Efficiency Advanced Lightweight Fuel Cell (HEAL-FC), Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Infinity's High Efficiency Advanced Lightweight Fuel Cell (HEAL FC) is an improved version of its current fuel cell technology developed for space applications. The...

  17. Basic Research Needs for Clean and Efficient Combustion of 21st Century Transportation Fuels

    Energy Technology Data Exchange (ETDEWEB)

    McIlroy, A.; McRae, G.; Sick, V.; Siebers, D. L.; Westbrook, C. K.; Smith, P. J.; Taatjes, C.; Trouve, A.; Wagner, A. F.; Rohlfing, E.; Manley, D.; Tully, F.; Hilderbrandt, R.; Green, W.; Marceau, D.; O' Neal, J.; Lyday, M.; Cebulski, F.; Garcia, T. R.; Strong, D.

    2006-11-01

    To identify basic research needs and opportunities underlying utilization of evolving transportation fuels, with a focus on new or emerging science challenges that have the potential for significant long-term impact on fuel efficiency and emissions.

  18. Automation for Accommodating Fuel-Efficient Descents in Constrained Airspace

    Science.gov (United States)

    Coopenbarger, Richard A.

    2010-01-01

    Continuous descents at low engine power are desired to reduce fuel consumption, emissions and noise during arrival operations. The challenge is to allow airplanes to fly these types of efficient descents without interruption during busy traffic conditions. During busy conditions today, airplanes are commonly forced to fly inefficient, step-down descents as airtraffic controllers work to ensure separation and maximize throughput. NASA in collaboration with government and industry partners is developing new automation to help controllers accommodate continuous descents in the presence of complex traffic and airspace constraints. This automation relies on accurate trajectory predictions to compute strategic maneuver advisories. The talk will describe the concept behind this new automation and provide an overview of the simulations and flight testing used to develop and refine its underlying technology.

  19. NREL Fuels and Engines Research: Maximizing Vehicle Efficiency and

    Science.gov (United States)

    chemistry, conversion, and combustion to the evaluation of advanced fuels in actual engines and vehicles . With fuel chemistry, our scientific discoveries start out small. We use quantum mechanical modeling to explore how fuels with varying chemistry interact with engine and vehicle design. At our Fuel Combustion

  20. Energy efficiency and potentials of cassava fuel ethanol in Guangxi region of China

    International Nuclear Information System (INIS)

    Dai Du; Hu Zhiyuan; Pu Gengqiang; Li He; Wang Chengtao

    2006-01-01

    The Guangxi Zhuang autonomous region has plentiful cassava resources, which is an ideal feedstock for fuel ethanol production. The Guangxi government intends to promote cassava fuel ethanol as a substitute for gasoline. The purpose of this study was to quantify the energy efficiency and potentials of a cassava fuel ethanol project in the Guangxi region based on a 100 thousand ton fuel ethanol demonstration plant at Qinzhou of Guangxi. The net energy value (NEV) and net renewable energy value (NREV) are presented to assess the energy and renewable energy efficiency of the cassava fuel ethanol system during its life cycle. The cassava fuel ethanol system was divided into five subsystems including the cassava plantation/treatment, ethanol conversion, denaturing, refueling and transportation. All the energy and energy related materials inputs to each subsystem were estimated at the primary energy level. The total energy inputs were allocated between the fuel ethanol and its coproducts with market value and replacement value methods. Available lands for a cassava plantation were investigated and estimated. The results showed that the cassava fuel ethanol system was energy and renewable energy efficient as indicated by positive NEV and NREV values that were 7.475 MJ/L and 7.881 MJ/L, respectively. Cassava fuel ethanol production helps to convert the non-liquid fuel into fuel ethanol that can be used for transportation. Through fuel ethanol production, one Joule of petroleum fuel, plus other forms of energy inputs such as coal, can produce 9.8 J of fuel ethanol. Cassava fuel ethanol can substitute for gasoline and reduce oil imports. With the cassava output in 2003, it can substitute for 166.107 million liters of gasoline. With the cassava output potential, it can substitute for 618.162 million liters of gasoline. Cassava fuel ethanol is more energy efficient than gasoline, diesel fuel and corn fuel ethanol but less efficient than biodiesel

  1. Demonstration of high efficiency intermediate-temperature solid oxide fuel cell based on lanthanum gallate electrolyte

    International Nuclear Information System (INIS)

    Inagaki, Toru; Nishiwaki, Futoshi; Kanou, Jirou; Yamasaki, Satoru; Hosoi, Kei; Miyazawa, Takashi; Yamada, Masaharu; Komada, Norikazu

    2006-01-01

    The Kansai Electric Power Co., Inc. (KEPCO) and Mitsubishi Materials Corporation (MMC) have been jointly developing intermediate-temperature solid oxide fuel cells (SOFCs). The operation temperatures between 600 and 800 o C were set as the target, which enable SOFC to use less expensive metallic separators for cell-stacking and to carry out internal reforming of hydrocarbon fuels. The electrolyte-supported planar-type cells were fabricated using highly conductive lanthanum gallate-based electrolyte, La(Sr)Ga(Mg,Co)O 3-δ , Ni-(CeO 2 ) 1-x (SmO 1.5 ) x cermet anode, and Sm(Sr)CoO 3-δ cathode. The 1 kW-class power generation modules were fabricated using a seal-less stack of the cells and metallic separators. The 1 kW-class prototype power generation system with the module was developed with the high performance cell, which showed the thermally self-sustainability. The system included an SOFC module, a dc-ac inverter, a desulfurizer, and a heat recovery unit. It provided stable ac power output of 1 kW with the electrical efficiency of 45% LHV based on ac output by using city gas as a fuel, which was considered to be excellent for such a small power generation system. And the hot water of 90 o C was obtained using high temperature off-gas from SOFC

  2. Demonstration of high efficiency intermediate-temperature solid oxide fuel cell based on lanthanum gallate electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Inagaki, Toru [Kansai Electric Power Co. Inc., Energy Use R and D Center, 11-20 Nakoji 3-chome, Amagasaki, Hyogo 661-0974 (Japan)]. E-mail: inagaki@rdd.kepco.co.jp; Nishiwaki, Futoshi [Kansai Electric Power Co. Inc., Energy Use R and D Center, 11-20 Nakoji 3-chome, Amagasaki, Hyogo 661-0974 (Japan); Kanou, Jirou [Kansai Electric Power Co. Inc., Energy Use R and D Center, 11-20 Nakoji 3-chome, Amagasaki, Hyogo 661-0974 (Japan); Yamasaki, Satoru [Kansai Electric Power Co. Inc., Energy Use R and D Center, 11-20 Nakoji 3-chome, Amagasaki, Hyogo 661-0974 (Japan); Hosoi, Kei [Mitsubishi Materials Corporation, Central Research Institute, 1002-14 Mukohyama, Naka-machi, Naka-gun, Ibaraki 311-0102 (Japan); Miyazawa, Takashi [Mitsubishi Materials Corporation, Central Research Institute, 1002-14 Mukohyama, Naka-machi, Naka-gun, Ibaraki 311-0102 (Japan); Yamada, Masaharu [Mitsubishi Materials Corporation, Central Research Institute, 1002-14 Mukohyama, Naka-machi, Naka-gun, Ibaraki 311-0102 (Japan); Komada, Norikazu [Mitsubishi Materials Corporation, Central Research Institute, 1002-14 Mukohyama, Naka-machi, Naka-gun, Ibaraki 311-0102 (Japan)

    2006-02-09

    The Kansai Electric Power Co., Inc. (KEPCO) and Mitsubishi Materials Corporation (MMC) have been jointly developing intermediate-temperature solid oxide fuel cells (SOFCs). The operation temperatures between 600 and 800 {sup o}C were set as the target, which enable SOFC to use less expensive metallic separators for cell-stacking and to carry out internal reforming of hydrocarbon fuels. The electrolyte-supported planar-type cells were fabricated using highly conductive lanthanum gallate-based electrolyte, La(Sr)Ga(Mg,Co)O{sub 3-{delta}}, Ni-(CeO{sub 2}){sub 1-x}(SmO{sub 1.5}) {sub x} cermet anode, and Sm(Sr)CoO{sub 3-{delta}} cathode. The 1 kW-class power generation modules were fabricated using a seal-less stack of the cells and metallic separators. The 1 kW-class prototype power generation system with the module was developed with the high performance cell, which showed the thermally self-sustainability. The system included an SOFC module, a dc-ac inverter, a desulfurizer, and a heat recovery unit. It provided stable ac power output of 1 kW with the electrical efficiency of 45% LHV based on ac output by using city gas as a fuel, which was considered to be excellent for such a small power generation system. And the hot water of 90 {sup o}C was obtained using high temperature off-gas from SOFC.

  3. Waste to Watts and Water: Enabling Self-Contained Facilities Using Microbial Fuel Cells

    Science.gov (United States)

    2009-03-01

    98; “Project to Turn Beer Wastewater into Power,” ; Yokoyama et al., “Treatment of Cow-Waste Slurry,” 634; Catal et al., “Electricity Production...Fuel Cells Bulletin 2006, no. 7 (2006): 7. “Project to Turn Beer Wastewater into Power.” Fuel Cells Bulletin 2007, no. 7 (2007): 11. Rabaey, K., J...Biomass Fermentation , edited by Piet Lens, Peter Westermann, Marianne Haberbauer, and Angelo Moreno, 377–400. Integrated Environmental Technology Series

  4. Energy efficiency with QoS control in dynamic optical networks with SDN enabled integrated control plane

    DEFF Research Database (Denmark)

    Wang, Jiayuan; Chen, Xin; Phillips, Chris

    2014-01-01

    The paper presents energy efficient routing algorithms based on a novel integrated control plane platform. The centralized control plane structure enables the use of flexible heuristic algorithms for route selection in optical networks. Differentiated routing for various traffic types is used in ...

  5. Notes on 'Hit-And-Run enables efficient weight generation for simulation-based multiple criteria decision analysis'

    NARCIS (Netherlands)

    van Valkenhoef, Gert; Tervonen, Tommi; Postmus, Douwe

    2014-01-01

    In our previous work published in this journal, we showed how the Hit-And-Run (HAR) procedure enables efficient sampling of criteria weights from a space formed by restricting a simplex with arbitrary linear inequality constraints. In this short communication, we note that the method for generating

  6. Design and optimization of automotive thermoelectric generators for maximum fuel efficiency improvement

    International Nuclear Information System (INIS)

    Kempf, Nicholas; Zhang, Yanliang

    2016-01-01

    Highlights: • A three-dimensional automotive thermoelectric generator (TEG) model is developed. • Heat exchanger design and TEG configuration are optimized for maximum fuel efficiency increase. • Heat exchanger conductivity has a strong influence on maximum fuel efficiency increase. • TEG aspect ratio and fin height increase with heat exchanger thermal conductivity. • A 2.5% fuel efficiency increase is attainable with nanostructured half-Heusler modules. - Abstract: Automotive fuel efficiency can be increased by thermoelectric power generation using exhaust waste heat. A high-temperature thermoelectric generator (TEG) that converts engine exhaust waste heat into electricity is simulated based on a light-duty passenger vehicle with a 4-cylinder gasoline engine. Strategies to optimize TEG configuration and heat exchanger design for maximum fuel efficiency improvement are provided. Through comparison of stainless steel and silicon carbide heat exchangers, it is found that both the optimal TEG design and the maximum fuel efficiency increase are highly dependent on the thermal conductivity of the heat exchanger material. Significantly higher fuel efficiency increase can be obtained using silicon carbide heat exchangers at taller fins and a longer TEG along the exhaust flow direction when compared to stainless steel heat exchangers. Accounting for major parasitic losses, a maximum fuel efficiency increase of 2.5% is achievable using newly developed nanostructured bulk half-Heusler thermoelectric modules.

  7. Trends in energy use and fuel efficiency in the US commercial airline industry

    Energy Technology Data Exchange (ETDEWEB)

    Smith, J.B.

    1981-12-01

    The record of the US commercial airline industry in improving fuel efficiency from 1973 to 1980 is examined. The components of the efficiency changes and how much fuel they saved are identified. The analysis focused only on the transportion of passengers, excluding helicopter service, commuter service, and flights devoted solely to transporting cargo. (MHR)

  8. Nuclear Energy R and D Imperative 3: Enable a Transition Away from Fossil Fuel in the Transportation and Industrial Sectors

    International Nuclear Information System (INIS)

    Petti, David; Herring, J. Stephen

    2010-01-01

    As described in the Department of Energy Office of Nuclear Energy's Nuclear Energy R and D Roadmap, nuclear energy can play a significant role in supplying energy for a growing economy while reducing both our dependence on foreign energy supplies and emissions from the burning of fossil fuels. The industrial and transportation sectors are responsible for more than half of the greenhouse gas emissions in the U.S., and imported oil supplies 70% of the energy used in the transportation sector. It is therefore important to examine the various ways nuclear energy can facilitate a transition away from fossil fuels to secure environmentally sustainable production and use of energy in the transportation and manufacturing industry sectors. Imperative 3 of the Nuclear Energy R and D Roadmap, entitled 'Enable a Transition Away from Fossil Fuels by Producing Process Heat for use in the Transportation and Industrial Sectors', addresses this need. This document presents an Implementation Plan for R and D efforts related to this imperative. The expanded use of nuclear energy beyond the electrical grid will contribute significantly to overcoming the three inter-linked energy challenges facing U.S. industry: the rising and volatile prices for premium fossil fuels such as oil and natural gas, dependence on foreign sources for these fuels, and the risks of climate change resulting from carbon emissions. Nuclear energy could be used in the industrial and transportation sectors to: (1) Generate high temperature process heat and electricity to serve industrial needs including the production of chemical feedstocks for use in manufacturing premium fuels and fertilizer products, (2) Produce hydrogen for industrial processes and transportation fuels, and (3) Provide clean water for human consumption by desalination and promote wastewater treatment using low-grade nuclear heat as a useful additional benefit. Opening new avenues for nuclear energy will significantly enhance our nation

  9. Learning networks as an enabler for informed decisions to target energy-efficiency potentials in companies

    NARCIS (Netherlands)

    Wohlfarth, Katharina; Eichhammer, W.A.; Schlomann, Barbara; Mielicke, Ursula

    2017-01-01

    his paper deals with possibilities of targeting energy efficiency potentials in German companies by delivering information and support within a cooperative management system “Learning Energy Efficiency Networks” (LEEN). Information deficits are pointed out as a relevant barrier to implementing

  10. Robust nonfullerene solar cells approaching unity external quantum efficiency enabled by suppression of geminate recombination.

    Science.gov (United States)

    Baran, Derya; Gasparini, Nicola; Wadsworth, Andrew; Tan, Ching Hong; Wehbe, Nimer; Song, Xin; Hamid, Zeinab; Zhang, Weimin; Neophytou, Marios; Kirchartz, Thomas; Brabec, Christoph J; Durrant, James R; McCulloch, Iain

    2018-05-25

    Nonfullerene solar cells have increased their efficiencies up to 13%, yet quantum efficiencies are still limited to 80%. Here we report efficient nonfullerene solar cells with quantum efficiencies approaching unity. This is achieved with overlapping absorption bands of donor and acceptor that increases the photon absorption strength in the range from about 570 to 700 nm, thus, almost all incident photons are absorbed in the active layer. The charges generated are found to dissociate with negligible geminate recombination losses resulting in a short-circuit current density of 20 mA cm -2 along with open-circuit voltages >1 V, which is remarkable for a 1.6 eV bandgap system. Most importantly, the unique nano-morphology of the donor:acceptor blend results in a substantially improved stability under illumination. Understanding the efficient charge separation in nonfullerene acceptors can pave the way to robust and recombination-free organic solar cells.

  11. Robust nonfullerene solar cells approaching unity external quantum efficiency enabled by suppression of geminate recombination

    KAUST Repository

    Baran, Derya; Gasparini, Nicola; Wadsworth, Andrew; Tan, Ching Hong; Wehbe, Nimer; Song, Xin; Hamid, Zeinab; Zhang, Weimin; Neophytou, Marios; Kirchartz, Thomas; Brabec, Christoph J.; Durrant, James R.; McCulloch, Iain

    2018-01-01

    Nonfullerene solar cells have increased their efficiencies up to 13%, yet quantum efficiencies are still limited to 80%. Here we report efficient nonfullerene solar cells with quantum efficiencies approaching unity. This is achieved with overlapping absorption bands of donor and acceptor that increases the photon absorption strength in the range from about 570 to 700 nm, thus, almost all incident photons are absorbed in the active layer. The charges generated are found to dissociate with negligible geminate recombination losses resulting in a short-circuit current density of 20 mA cm-2 along with open-circuit voltages >1 V, which is remarkable for a 1.6 eV bandgap system. Most importantly, the unique nano-morphology of the donor:acceptor blend results in a substantially improved stability under illumination. Understanding the efficient charge separation in nonfullerene acceptors can pave the way to robust and recombination-free organic solar cells.

  12. Robust nonfullerene solar cells approaching unity external quantum efficiency enabled by suppression of geminate recombination

    KAUST Repository

    Baran, Derya

    2018-05-21

    Nonfullerene solar cells have increased their efficiencies up to 13%, yet quantum efficiencies are still limited to 80%. Here we report efficient nonfullerene solar cells with quantum efficiencies approaching unity. This is achieved with overlapping absorption bands of donor and acceptor that increases the photon absorption strength in the range from about 570 to 700 nm, thus, almost all incident photons are absorbed in the active layer. The charges generated are found to dissociate with negligible geminate recombination losses resulting in a short-circuit current density of 20 mA cm-2 along with open-circuit voltages >1 V, which is remarkable for a 1.6 eV bandgap system. Most importantly, the unique nano-morphology of the donor:acceptor blend results in a substantially improved stability under illumination. Understanding the efficient charge separation in nonfullerene acceptors can pave the way to robust and recombination-free organic solar cells.

  13. Energy and fuel efficient parallel mild hybrids for urban roads

    International Nuclear Information System (INIS)

    Babu, Ajay; Ashok, S.

    2016-01-01

    Highlights: • Energy and fuel savings depend on battery charge variations and the vehicle speed parameters. • Indian urban conditions provide lot of scope for energy and fuel savings in mild hybrids. • Energy saving strategy has lower payback periods than the fuel saving one in mild hybrids. • Sensitivity to parameter variations is the least for energy saving strategy in a mild hybrid. - Abstract: Fuel economy improvements and battery energy savings can promote the adoption of parallel mild hybrids for urban driving conditions. The aim of this study is to establish these benefits through two operating modes: an energy saving mode and a fuel saving mode. The performances of a typical parallel mild hybrid using these modes were analysed over urban driving cycles, in the US, Europe, and India, with a particular focus on the Indian urban conditions. The energy pack available from the proposed energy-saving operating mode, in addition to the energy already available from the conventional mode, was observed to be the highest for the representative urban driving cycle of the US. The extra energy pack available was found to be approximately 21.9 times that available from the conventional mode. By employing the proposed fuel saving operating mode, the fuel economy improvement achievable in New York City was observed to be approximately 22.69% of the fuel economy with the conventional strategy. The energy saving strategy was found to possess the lowest payback periods and highest immunity to variations in various cost parameters.

  14. Spectral-Efficiency - Illumination Pareto Front for Energy Harvesting Enabled VLC System

    KAUST Repository

    Abdelhady, Amr Mohamed Abdelaziz; Amin, Osama; Chaaban, Anas; Alouini, Mohamed-Slim

    2017-01-01

    . The adopted optical system provides users with illumination and data communication services. The outdoor optical design objective is to maximize the illumination, while the communication design objective is to maximize the spectral efficiency (SE). The design

  15. Solution-processable MoOx nanocrystals enable highly efficient reflective and semitransparent polymer solar cells

    KAUST Repository

    Jagadamma, Lethy Krishnan; Hu, Hanlin; Kim, Taesoo; Ngongang Ndjawa, Guy Olivier; Mansour, Ahmed; El Labban, Abdulrahman; Faria, Jorge C.D.; Munir, Rahim; Anjum, Dalaver H.; McLachlan, Martyn A.; Amassian, Aram

    2016-01-01

    Solution-manufacturing of organic solar cells with best-in-class power conversion efficiency (PCE) will require all layers to be solution-coated without compromising solar cell performance. To date, the hole transporting layer (HTL) deposited on top

  16. Quantitative Imaging of Turbulent Mixing Dynamics in High-Pressure Fuel Injection to Enable Predictive Simulations of Engine Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Frank, Jonathan H. [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Reacting Flows Dept.; Pickett, Lyle M. [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Engine Combustion Dept.; Bisson, Scott E. [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Remote Sensing and Energetic Materials Dept.; Patterson, Brian D. [Sandia National Lab. (SNL-CA), Livermore, CA (United States). combustion Chemistry Dept.; Ruggles, Adam J. [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Reacting Flows Dept.; Skeen, Scott A. [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Engine Combustion Dept.; Manin, Julien Luc [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Engine Combustion Dept.; Huang, Erxiong [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Reacting Flows Dept.; Cicone, Dave J. [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Engine Combustion Dept.; Sphicas, Panos [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Engine Combustion Dept.

    2015-09-01

    In this LDRD project, we developed a capability for quantitative high - speed imaging measurements of high - pressure fuel injection dynamics to advance understanding of turbulent mixing in transcritical flows, ignition, and flame stabilization mechanisms, and to provide e ssential validation data for developing predictive tools for engine combustion simulations. Advanced, fuel - efficient engine technologies rely on fuel injection into a high - pressure, high - temperature environment for mixture preparation and com bustion. Howe ver, the dynamics of fuel injection are not well understood and pose significant experimental and modeling challenges. To address the need for quantitative high - speed measurements, we developed a Nd:YAG laser that provides a 5ms burst of pulses at 100 kHz o n a robust mobile platform . Using this laser, we demonstrated s patially and temporally resolved Rayleigh scattering imaging and particle image velocimetry measurements of turbulent mixing in high - pressure gas - phase flows and vaporizing sprays . Quantitativ e interpretation of high - pressure measurements was advanced by reducing and correcting interferences and imaging artifacts.

  17. Light enables a very high efficiency of carbon storage in developing embryos of rapeseed.

    Science.gov (United States)

    Goffman, Fernando D; Alonso, Ana P; Schwender, Jörg; Shachar-Hill, Yair; Ohlrogge, John B

    2005-08-01

    The conversion of photosynthate to seed storage reserves is crucial to plant fitness and agricultural production, yet quantitative information about the efficiency of this process is lacking. To measure metabolic efficiency in developing seeds, rapeseed (Brassica napus) embryos were cultured in media in which all carbon sources were [U-14C]-labeled and their conversion into CO2, oil, protein, and other biomass was determined. The conversion efficiency of the supplied carbon into seed storage reserves was very high. When provided with 0, 50, or 150 micromol m(-2) s(-1) light, the proportion of carbon taken up by embryos that was recovered in biomass was 60% to 64%, 77% to 86%, and 85% to 95%, respectively. Light not only improved the efficiency of carbon storage, but also increased the growth rate, the proportion of 14C recovered in oil relative to protein, and the fixation of external 14CO2 into biomass. Embryos grown at 50 micromol m(-2) s(-1) in the presence of 5 microM 1,1-dimethyl-3-(3,4-dichlorophenyl) urea (an inhibitor of photosystem II) were reduced in total biomass and oil synthesis by 3.2-fold and 2.8-fold, respectively, to the levels observed in the dark. To explore if the reduced growth and carbon conversion efficiency in dark were related to oxygen supplied by photosystem II, embryos and siliques were cultured with increased oxygen. The carbon conversion efficiency of embryos remained unchanged when oxygen levels were increased 3-fold. Increasing the O2 levels surrounding siliques from 21% to 60% did not increase oil synthesis rates either at 1,000 micromol m(-2) s(-1) or in the dark. We conclude that light increases the growth, efficiency of carbon storage, and oil synthesis in developing rapeseed embryos primarily by providing reductant and/or ATP.

  18. Light Enables a Very High Efficiency of Carbon Storage in Developing Embryos of Rapeseed1

    Science.gov (United States)

    Goffman, Fernando D.; Alonso, Ana P.; Schwender, Jörg; Shachar-Hill, Yair; Ohlrogge, John B.

    2005-01-01

    The conversion of photosynthate to seed storage reserves is crucial to plant fitness and agricultural production, yet quantitative information about the efficiency of this process is lacking. To measure metabolic efficiency in developing seeds, rapeseed (Brassica napus) embryos were cultured in media in which all carbon sources were [U-14C]-labeled and their conversion into CO2, oil, protein, and other biomass was determined. The conversion efficiency of the supplied carbon into seed storage reserves was very high. When provided with 0, 50, or 150 μmol m−2 s−1 light, the proportion of carbon taken up by embryos that was recovered in biomass was 60% to 64%, 77% to 86%, and 85% to 95%, respectively. Light not only improved the efficiency of carbon storage, but also increased the growth rate, the proportion of 14C recovered in oil relative to protein, and the fixation of external 14CO2 into biomass. Embryos grown at 50 μmol m−2 s−1 in the presence of 5 μm 1,1-dimethyl-3-(3,4-dichlorophenyl) urea (an inhibitor of photosystem II) were reduced in total biomass and oil synthesis by 3.2-fold and 2.8-fold, respectively, to the levels observed in the dark. To explore if the reduced growth and carbon conversion efficiency in dark were related to oxygen supplied by photosystem II, embryos and siliques were cultured with increased oxygen. The carbon conversion efficiency of embryos remained unchanged when oxygen levels were increased 3-fold. Increasing the O2 levels surrounding siliques from 21% to 60% did not increase oil synthesis rates either at 1,000 μmol m−2 s−1 or in the dark. We conclude that light increases the growth, efficiency of carbon storage, and oil synthesis in developing rapeseed embryos primarily by providing reductant and/or ATP. PMID:16024686

  19. Modeling efficiency and water balance in PEM fuel cell systems with liquid fuel processing and hydrogen membranes

    Science.gov (United States)

    Pearlman, Joshua B.; Bhargav, Atul; Shields, Eric B.; Jackson, Gregory S.; Hearn, Patrick L.

    Integrating PEM fuel cells effectively with liquid hydrocarbon reforming requires careful system analysis to assess trade-offs associated with H 2 production, purification, and overall water balance. To this end, a model of a PEM fuel cell system integrated with an autothermal reformer for liquid hydrocarbon fuels (modeled as C 12H 23) and with H 2 purification in a water-gas-shift/membrane reactor is developed to do iterative calculations for mass, species, and energy balances at a component and system level. The model evaluates system efficiency with parasitic loads (from compressors, pumps, and cooling fans), system water balance, and component operating temperatures/pressures. Model results for a 5-kW fuel cell generator show that with state-of-the-art PEM fuel cell polarization curves, thermal efficiencies >30% can be achieved when power densities are low enough for operating voltages >0.72 V per cell. Efficiency can be increased by operating the reformer at steam-to-carbon ratios as high as constraints related to stable reactor temperatures allow. Decreasing ambient temperature improves system water balance and increases efficiency through parasitic load reduction. The baseline configuration studied herein sustained water balance for ambient temperatures ≤35 °C at full power and ≤44 °C at half power with efficiencies approaching ∼27 and ∼30%, respectively.

  20. Economic Efficiency of Establishing Domestic Production of Synthetic Liquid Fuel

    Directory of Open Access Journals (Sweden)

    Kyzym Mykola O.

    2017-06-01

    Full Text Available The article notes a stable tendency to increasing the oil dependence of Ukraine, which creates a threat to the national economic security, and proves an expediency of establishing domestic production of synthetic liquid fuel. The technical, organizational and economic features of establishing synthetic liquid fuel production in Ukraine are presented. There proved a hypothesis on the expediency of organizing the production of synthetic liquid fuels based on steam-plasma coal gasification technology. The forecast resource cycle of the country until 2020 under conditions of developing this technology is modeled.

  1. Enabling Energy Efficiency in South Africa's Commercial Buildings

    Energy Technology Data Exchange (ETDEWEB)

    2016-04-01

    South Africa is leading a number of efforts to support a thriving economy while also reducing energy use. Increasing energy demand coupled with a highly energy intensive economy and energy inefficient industries provide the backdrop for strong government action underway in South Africa. This brochure details how the Clean Energy Solutions Center supported development of the Regulations on Allowance for the Energy Efficiency Savings legislation designed to provide a framework for effective energy efficiency regulation, incentives and energy reduction targets for South Africa's commercial buildings sector.

  2. Nickel(0)-catalyzed enantioselective annulations of alkynes and arylenoates enabled by a chiral NHC ligand: efficient access to cyclopentenones.

    Science.gov (United States)

    Ahlin, Joachim S E; Donets, Pavel A; Cramer, Nicolai

    2014-11-24

    Cyclopentenones are versatile structural motifs of natural products as well as reactive synthetic intermediates. The nickel-catalyzed reductive [3+2] cycloaddition of α,β-unsaturated aromatic esters and alkynes constitutes an efficient method for their synthesis. Here, nickel(0) catalysts comprising a chiral bulky C1-symmetric N-heterocyclic carbene ligand were shown to enable an efficient asymmetric synthesis of cyclopentenones from mesityl enoates and internal alkynes under mild conditions. The bulky NHC ligand provided the cyclopentenone products in very high enantioselectivity and led to a regioselective incorporation of unsymmetrically substituted alkynes. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Solid oxide fuel cells for transportation: A clean, efficient alternative for propulsion

    International Nuclear Information System (INIS)

    Kumar, R.; Krumpelt, M.; Myles, K.M.

    1993-01-01

    Fuel cells show great promise for providing clean and efficient transportation power. Of the fuel cell propulsion systems under investigation, the solid oxide fuel cell (SOFC) is particularly attractive for heavy duty transportation applications that have a relatively long duty cycle, such as locomotives, trucks, and barges. Advantages of the SOFC include a simple, compact system configuration; inherent fuel flexibility for hydrocarbon and alternative fuels; and minimal water management. The specific advantages of the SOFC for powering a railroad locomotive are examined. Feasibility, practicality, and safety concerns regarding SOFCs in transportation applications are discussed, as am the major R ampersand D issues

  4. SEA for strategic grid planning in South Africa: Enabling the efficient and effective roll out of strategic electricity transmission infrastructure

    CSIR Research Space (South Africa)

    Fischer, TD

    2016-05-01

    Full Text Available | Resilience and Sustainability 36th Annual Conference of the International Association for Impact Assessment 11 - 14 May 2016 | Nagoya Congress Center | Aichi-Nagoya | Japan | www.iaia.org SEA FOR STRATEGIC GRID PLANNING IN SOUTH AFRICA: Enabling... the efficient and effective roll out of strategic electricity transmission infrastructure Abstract ID: 409 Authors: Marshall Mabin(1) , Paul Lochner and Dee Fischer Council for Scientific and Industrial Research (CSIR), PO Box 320 Stellenbosch 7599 South...

  5. Fuel demand and fuel efficiency in the US commercial-airline industry and the trucking industry: an analysis of trends and implications. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1982-03-31

    A study of trends in fuel use and efficiency in the US commercial airlines industry is extended back to 1967 in order to compare the relative contributions of the factors influencing efficiency during a period of stable fuel prices (1967 to 1972) versus a period of fuel price growth (1973 to 1980). A similar analysis disaggregates the components of truck efficiency and evaluates their relative impact on fuel consumption in the trucking industry. (LEW)

  6. Tailoring the Energy Landscape in Quasi-2D Halide Perovskites Enables Efficient Green-Light Emission

    KAUST Repository

    Quan, Li Na; Zhao, Yongbiao; Garcí a de Arquer, F. Pelayo; Sabatini, Randy; Walters, Grant; Voznyy, Oleksandr; Comin, Riccardo; Li, Yiying; Fan, James Z.; Tan, Hairen; Pan, Jun; Yuan, Mingjian; Bakr, Osman; Lu, Zhenghong; Kim, Dong Ha; Sargent, Edward H.

    2017-01-01

    Organo-metal halide perovskites are a promising platform for optoelectronic applications in view of their excellent charge-transport and bandgap tunability. However, their low photoluminescence quantum efficiencies, especially in low-excitation regimes, limit their efficiency for light emission. Consequently, perovskite light-emitting devices are operated under high injection, a regime under which the materials have so far been unstable. Here we show that, by concentrating photoexcited states into a small subpopulation of radiative domains, one can achieve a high quantum yield, even at low excitation intensities. We tailor the composition of quasi-2D perovskites to direct the energy transfer into the lowest-bandgap minority phase and to do so faster than it is lost to nonradiative centers. The new material exhibits 60% photoluminescence quantum yield at excitation intensities as low as 1.8 mW/cm2, yielding a ratio of quantum yield to excitation intensity of 0.3 cm2/mW; this represents a decrease of 2 orders of magnitude in the excitation power required to reach high efficiency compared with the best prior reports. Using this strategy, we report light-emitting diodes with external quantum efficiencies of 7.4% and a high luminescence of 8400 cd/m2.

  7. Tailoring the Energy Landscape in Quasi-2D Halide Perovskites Enables Efficient Green-Light Emission

    KAUST Repository

    Quan, Li Na

    2017-05-10

    Organo-metal halide perovskites are a promising platform for optoelectronic applications in view of their excellent charge-transport and bandgap tunability. However, their low photoluminescence quantum efficiencies, especially in low-excitation regimes, limit their efficiency for light emission. Consequently, perovskite light-emitting devices are operated under high injection, a regime under which the materials have so far been unstable. Here we show that, by concentrating photoexcited states into a small subpopulation of radiative domains, one can achieve a high quantum yield, even at low excitation intensities. We tailor the composition of quasi-2D perovskites to direct the energy transfer into the lowest-bandgap minority phase and to do so faster than it is lost to nonradiative centers. The new material exhibits 60% photoluminescence quantum yield at excitation intensities as low as 1.8 mW/cm2, yielding a ratio of quantum yield to excitation intensity of 0.3 cm2/mW; this represents a decrease of 2 orders of magnitude in the excitation power required to reach high efficiency compared with the best prior reports. Using this strategy, we report light-emitting diodes with external quantum efficiencies of 7.4% and a high luminescence of 8400 cd/m2.

  8. Technical basis for the proposed high efficiency nuclear fuel program

    International Nuclear Information System (INIS)

    MacDonald, P.E.; Herring, J.S.; Crawford, D.C.; Neimark, L.E.

    1999-01-01

    Greenhouse gas emissions from fossil fired electricity generating stations will dramatically increase over the next 20 years. Nuclear energy is the only fully developed technology able to supply large amounts of electricity without generation of greenhouse gases. However, the problem of noncompetitive economics and public concerns about radioactive waste disposal, safety, and nuclear weapons proliferation may prevent the reemergence of nuclear power as a preferred option for new electric energy generation in the U.S. This paper discusses a new research program to help address these issues, by developing fuel designs capable of burnup values in excess of 60 MWD/kgU. The objectives of the program are to: improve the reliability and robustness of light water reactor fuel, thereby improving safety margins; Significantly increase the energy generated by each fuel loading, thereby achieving longer operating cycles, higher capacity factors, and lower cost electric power; Significantly reduce the volume of spent nuclear fuel discharged for disposal by allowing more energy to be extracted from each fuel element prior to discharge; Develop fuel that is much more proliferation resistant. (author)

  9. Market Analysis and Consumer Impacts Source Document. Part III. Consumer Behavior and Attitudes Toward Fuel Efficient Vehicles

    Science.gov (United States)

    1980-12-01

    This source document on motor vehicle market analysis and consumer impacts consists of three parts. Part III consists of studies and reviews on: consumer awareness of fuel efficiency issues; consumer acceptance of fuel efficient vehicles; car size ch...

  10. Primer on Motor Fuel Excise Taxes and the Role of Alternative Fuels and Energy Efficient Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Schroeder, Alex [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2015-08-26

    Motor fuel taxes were established to finance our nation’s transportation infrastructure, yet evolving economic, political, and technological influences are constraining this ability. At the federal level, the Highway Trust Fund (HTF), which is primarily funded by motor fuel taxes, has become increasingly dependent on general fund contributions and short-term reauthorizations to prevent insolvency. As a result, there are discussions at both the federal and state levels in which stakeholders are examining the future of motor fuel excise taxes as well as the role of electric and alternative fuel vehicles in that future. On July 1, 2015, six states increased their motor fuel tax rates.

  11. Efficiency improvement of nuclear power plant operation: the significant role of advanced nuclear fuel technologies

    International Nuclear Information System (INIS)

    Velde Van de, A.; Burtak, F.

    2001-01-01

    Due to the increased liberalisation of the power markets, nuclear power generation is being exposed to high cost reduction pressure. In this paper we highlight the role of advanced nuclear fuel technologies to reduce the fuel cycle costs and therefore increase the efficiency of nuclear power plant operation. The key factor is a more efficient utilisation of the fuel and present developments at Siemens are consequently directed at (i) further increase of batch average burnup, (ii) improvement of fuel reliability, (iii) enlargement of fuel operation margins and (iv) improvement of methods for fuel design and core analysis. As a result, the nuclear fuel cycle costs for a typical LWR have been reduced during the past decades by about US$ 35 million per year. The estimated impact of further burnup increases on the fuel cycle costs is expected to be an additional saving of US$10 - 15 million per year. Due to the fact that the fuel will operate closer to design limits, a careful approach is required when introducing advanced fuel features in reload quantities. Trust and co-operation between the fuel vendors and the utilities is a prerequisite for the common success. (authors)

  12. Diffractive intermediate layer enables broadband light trapping for high efficiency ultrathin c-Si tandem cells

    Energy Technology Data Exchange (ETDEWEB)

    Li, Guijun, E-mail: gliad@connect.ust.hk; Ho, Jacob Y. L.; Li, He; Kwok, Hoi-Sing [State Key Laboratory on Advanced Displays and Optoelectronics Technologies, Department of Electronic and Computer Engineering, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon (Hong Kong)

    2014-06-09

    Light management through the intermediate reflector in the tandem cell configuration is of great practical importance for achieving high stable efficiency and also low cost production. So far, however, the intermediate reflectors employed currently are mainly focused on the light absorption enhancement of the top cell. Here, we present a diffractive intermediate layer that allows for light trapping over a broadband wavelength for the ultrathin c-Si tandem solar cell. Compared with the standard intermediate reflector, this nanoscale architectural intermediate layer results in a 35% and 21% remarkable enhancement of the light absorption in the top (400–800 nm) and bottom (800–1100 nm) cells simultaneously, and ultrathin c-Si tandem cells with impressive conversion efficiency of 13.3% are made on the glass substrate.

  13. Diffractive intermediate layer enables broadband light trapping for high efficiency ultrathin c-Si tandem cells

    International Nuclear Information System (INIS)

    Li, Guijun; Ho, Jacob Y. L.; Li, He; Kwok, Hoi-Sing

    2014-01-01

    Light management through the intermediate reflector in the tandem cell configuration is of great practical importance for achieving high stable efficiency and also low cost production. So far, however, the intermediate reflectors employed currently are mainly focused on the light absorption enhancement of the top cell. Here, we present a diffractive intermediate layer that allows for light trapping over a broadband wavelength for the ultrathin c-Si tandem solar cell. Compared with the standard intermediate reflector, this nanoscale architectural intermediate layer results in a 35% and 21% remarkable enhancement of the light absorption in the top (400–800 nm) and bottom (800–1100 nm) cells simultaneously, and ultrathin c-Si tandem cells with impressive conversion efficiency of 13.3% are made on the glass substrate.

  14. Design of energy efficient optical networks with software enabled integrated control plane

    DEFF Research Database (Denmark)

    Wang, Jiayuan; Yan, Ying; Dittmann, Lars

    2015-01-01

    energy consumption by proposing a new integrated control plane structure utilising Software Defined Networking technologies. The integrated control plane increases the efficiencies of exchanging control information across different network domains, while introducing new possibilities to the routing...... methods and the control over quality of service (QoS). The structure is defined as an overlay generalised multi-protocol label switching (GMPLS) control model. With the defined structure, the integrated control plane is able to gather information from different domains (i.e. optical core network......'s) routing behaviours. With the flexibility of the routing structure, results show that the energy efficiency of the network can be improved without compromising the QoS for delay/blocking sensitive services....

  15. Photonic compressive sensing enabled data efficient time stretch optical coherence tomography

    Science.gov (United States)

    Mididoddi, Chaitanya K.; Wang, Chao

    2018-03-01

    Photonic time stretch (PTS) has enabled real time spectral domain optical coherence tomography (OCT). However, this method generates a torrent of massive data at GHz stream rate, which requires capturing as per Nyquist principle. If the OCT interferogram signal is sparse in Fourier domain, which is always true for samples with limited number of layers, it can be captured at lower (sub-Nyquist) acquisition rate as per compressive sensing method. In this work we report a data compressed PTS-OCT system based on photonic compressive sensing with 66% compression with low acquisition rate of 50MHz and measurement speed of 1.51MHz per depth profile. A new method has also been proposed to improve the system with all-optical random pattern generation, which completely avoids electronic bottleneck in traditional binary pseudorandom binary sequence (PRBS) generators.

  16. Fuel flexible distributed combustion for efficient and clean gas turbine engines

    International Nuclear Information System (INIS)

    Khalil, Ahmed E.E.; Gupta, Ashwani K.

    2013-01-01

    Highlights: • Examined distributed combustion for gas turbines applications using HiTAC. • Gaseous, liquid, conventional and bio-fuels are examined with ultra-low emissions. • Novel design of fuel flexibility without any atomizer for liquid fuel sprays. • Demonstrated fuel flexibility with emissions x and CO, low noise, enhanced stability, higher efficiency and alleviation of combustion instability. Distributed reaction conditions were achieved using swirl for desirable controlled mixing between the injected air, fuel and hot reactive gases from within the combustor prior to mixture ignition. In this paper, distributed combustion is further investigated using a variety of fuels. Gaseous (methane, diluted methane, hydrogen enriched methane and propane) and liquid fuels, including both traditional (kerosene) and alternate fuels (ethanol) that cover a wide range of calorific values are investigated with emphasis on pollutants emission and combustor performance with each fuel. For liquid fuels, no atomization or spray device was used. Performance evaluation with the different fuels was established to outline the flexibility of the combustor using a wide range of fuels of different composition, phase and calorific value with specific focus on ultra-low pollutants emission. Results obtained on pollutants emission and OH * chemiluminescence for the specific fuels at various equivalence ratios are presented. Near distributed combustion conditions with less than 8 PPM of NO emission were demonstrated under novel premixed conditions for the various fuels tested at heat (energy) release intensity (HRI) of 27 MW/m 3 -atm. and a rather high equivalence ratio of 0.6. Higher equivalence ratios lacked favorable distributed combustion conditions. For the same conditions, CO emission varied for each fuel; less than 10 ppm were demonstrated for methane based fuels, while heavier liquid fuels provided less than 40 ppm CO emissions. Lower emissions of NO ( x can be possible by

  17. Analysis of DC/DC Converter Efficiency for Energy Storage System Based on Bidirectional Fuel Cells

    DEFF Research Database (Denmark)

    Pittini, Riccardo; Zhang, Zhe; Andersen, Michael A. E.

    2013-01-01

    interface to the grid. In power electronics, the converter efficiency is characterized at fixed operating voltage for various output power. This type of characterization is not suitable for fuel cells, since as the power from the fuel cell increases, the cell voltage decreases. This paper analyses how......Renewable energy sources are fluctuating depending on the availability of the energy source. For this reason, energy storage is becoming more important and bidirectional fuel cells represent an attractive technology. Fuel cells require highcurrent low-voltage dc-dc or dc-ac converters as power...... the fuel cell I-V characteristics influences the power electronics converter efficiency and their consequence on the overall system. A loaddependent efficiency curve is presented based on experimental results from a 6 kW dc-dc converter prototype including the most suitable control strategy which maximizes...

  18. Pyroprocessing oxide spent nuclear fuels for efficient disposal

    International Nuclear Information System (INIS)

    McPheeters, C.C.; Pierce, R.D.; Mulcahey, T.P.

    1994-01-01

    Pyrochemical processing as a means for conditioning spent nuclear fuels for disposal offers significant advantages over the direct disposal option. The advantages include reduction in high-level waste volume; conversion of most of the high-level waste to a low-level waste in which nearly all the transuranics (TRU) have been removed; and incorporation of the TRUs into a stable, highly radioactive waste form suitable for interim storage, ultimate destruction, or repository disposal. The lithium process has been under development at Argonne National Laboratory for use in pyrochemical conditioning of spent fuel for disposal. All of the process steps have been demonstrated in small-scale (0.5-kg simulated spent fuel) experiments. Engineering-scale (20-kg simulated spent fuel) demonstration of the process is underway, and small-scale experiments have been conducted with actual spent fuel from a light water reactor (LWR). The lithium process is simple, operates at relatively low temperatures, and can achieve high decontamination factors for the TRU elements. Ordinary materials, such as carbon steel, can be used for process containment

  19. A Cloud Computing-Enabled Spatio-Temporal Cyber-Physical Information Infrastructure for Efficient Soil Moisture Monitoring

    Directory of Open Access Journals (Sweden)

    Lianjie Zhou

    2016-06-01

    Full Text Available Comprehensive surface soil moisture (SM monitoring is a vital task in precision agriculture applications. SM monitoring includes remote sensing imagery monitoring and in situ sensor-based observational monitoring. Cloud computing can increase computational efficiency enormously. A geographical web service was developed to assist in agronomic decision making, and this tool can be scaled to any location and crop. By integrating cloud computing and the web service-enabled information infrastructure, this study uses the cloud computing-enabled spatio-temporal cyber-physical infrastructure (CESCI to provide an efficient solution for soil moisture monitoring in precision agriculture. On the server side of CESCI, diverse Open Geospatial Consortium web services work closely with each other. Hubei Province, located on the Jianghan Plain in central China, is selected as the remote sensing study area in the experiment. The Baoxie scientific experimental field in Wuhan City is selected as the in situ sensor study area. The results show that the proposed method enhances the efficiency of remote sensing imagery mapping and in situ soil moisture interpolation. In addition, the proposed method is compared to other existing precision agriculture infrastructures. In this comparison, the proposed infrastructure performs soil moisture mapping in Hubei Province in 1.4 min and near real-time in situ soil moisture interpolation in an efficient manner. Moreover, an enhanced performance monitoring method can help to reduce costs in precision agriculture monitoring, as well as increasing agricultural productivity and farmers’ net-income.

  20. Energy Conversion Efficiency Potential for Forward-Deployed Generation Using Direct Carbon Fuel Cells

    Science.gov (United States)

    2012-05-01

    fuel cells vs. DCFCs. PEMFC PAFC MCFC SOFC DCFC Electrolyte Polymer Phosphoric acid Molten car- bonate salt Ceramic Fused KNO3 Operating...air O2/air CO2/O2/air O2/air Humidified air Efficiency (Higher Heating Value [HHV]) 30–35% 40–50% 50–60% 45–55% 80% PEMFC : Proton Exchange... PEMFC proton-exchange membrane fuel cell SOFC solid oxide fuel cell SRI Statistical Research, Inc. TR technical report TRL technology readiness level

  1. Thermal efficiency and particulate pollution estimation of four biomass fuels grown on wasteland

    Energy Technology Data Exchange (ETDEWEB)

    Kandpal, J.B.; Madan, M. [Indian Inst. of Tech., New Delhi (India). Centre for Rural Development and Technology

    1996-10-01

    The thermal performance and concentration of suspended particulate matter were studied for 1-hour combustion of four biomass fuels, namely Acacia nilotica, Leucaena leucocepholea, Jatropha curcus, and Morus alba grown in wasteland. Among the four biomass fuels, the highest thermal efficiency was achieved with Acacia nilotica. The suspended particulate matter concentration for 1-hour combustion of four biomass fuels ranged between 850 and 2,360 {micro}g/m{sup 3}.

  2. High Efficiency of Mixed Th-U Fuel Utilisation in Innovative Nuclear Burning Wave Reactor

    International Nuclear Information System (INIS)

    Fomin, Sergii; Fomin, A.; Mel’nik, Yu.; Pilipenko, V.; Shul’ga, N.

    2013-01-01

    The presentation provides information about nuclear fuel reproduction and the U-Pu fuel cycle; the history of the Breed and Burn concept and the traveling wave concept; the non-stationary theory of nuclear burning wave; the Nuclear Burning Wave in Fast Reactor with U-Pu Fuel; nuclear burning wave in 5m length cylindrical FR for different reactor radius R and about the Reactor Power Control by Reflector Efficiency

  3. A novel 3D detector configuration enabling high quantum efficiency, low crosstalk, and low output capacitance

    International Nuclear Information System (INIS)

    Aurola, A.; Marochkin, V.; Tuuva, T.

    2016-01-01

    The benefits of pixelated planar direct conversion semiconductor radiation detectors comprising a thick fully depleted substrate are that they offer low crosstalk, small output capacitance, and that the planar configuration simplifies manufacturing. In order to provide high quantum efficiency for high energy X-rays and Gamma-rays such a radiation detector should be as thick as possible. The maximum thickness and thus the maximum quantum efficiency has been limited by the substrate doping concentration: the lower the substrate doping the thicker the detector can be before reaching the semiconductor material's electric breakdown field. Thick direct conversion semiconductor detectors comprising vertical three-dimensional electrodes protruding through the substrate have been previously proposed by Sherwood Parker in order to promote rapid detection of radiation. An additional advantage of these detectors is that their thickness is not limited by the substrate doping, i.e., the size of the maximum electric field value in the detector does not depend on detector thickness. However, the thicker the substrate of such three dimensional detectors is the larger the output capacitance is and thus the larger the output noise is. In the novel direct conversion pixelated radiation detector utilizing a novel three dimensional semiconductor architecture, which is proposed in this work, the detector thickness is not limited by the substrate doping and the output capacitance is small and does not depend on the detector thickness. In addition, by incorporating an additional node to the novel three-dimensional semiconductor architecture it can be utilized as a high voltage transistor that can deliver current across high voltages. Furthermore, it is possible to connect a voltage difference of any size to the proposed novel three dimensional semiconductor architecture provided that it is thick enough—this is a novel feature that has not been previously possible for semiconductor

  4. Order enables efficient electron-hole separation at an organic heterojunction with a small energy loss

    KAUST Repository

    Menke, S. Matthew

    2018-01-12

    Donor–acceptor organic solar cells often show low open-circuit voltages (VOC) relative to their optical energy gap (Eg) that limit power conversion efficiencies to ~12%. This energy loss is partly attributed to the offset between Eg and that of intermolecular charge transfer (CT) states at the donor–acceptor interface. Here we study charge generation occurring in PIPCP:PC61BM, a system with a very low driving energy for initial charge separation (Eg−ECT ~ 50 meV) and a high internal quantum efficiency (ηIQE ~ 80%). We track the strength of the electric field generated between the separating electron-hole pair by following the transient electroabsorption optical response, and find that while localised CT states are formed rapidly (<100 fs) after photoexcitation, free charges are not generated until 5 ps after photogeneration. In PIPCP:PC61BM, electronic disorder is low (Urbach energy <27 meV) and we consider that free charge separation is able to outcompete trap-assisted non-radiative recombination of the CT state.

  5. The four-flipper swimming method of plesiosaurs enabled efficient and effective locomotion.

    Science.gov (United States)

    Muscutt, Luke E; Dyke, Gareth; Weymouth, Gabriel D; Naish, Darren; Palmer, Colin; Ganapathisubramani, Bharathram

    2017-08-30

    The extinct ocean-going plesiosaurs were unique within vertebrates because they used two flipper pairs identical in morphology for propulsion. Although fossils of these Mesozoic marine reptiles have been known for more than two centuries, the function and dynamics of their tandem-flipper propulsion system has always been unclear and controversial. We address this question quantitatively for the first time in this study, reporting a series of precisely controlled water tank experiments that use reconstructed plesiosaur flippers scaled from well-preserved fossils. Our aim was to determine which limb movements would have resulted in the most efficient and effective propulsion. We show that plesiosaur hind flippers generated up to 60% more thrust and 40% higher efficiency when operating in harmony with their forward counterparts, when compared with operating alone, and the spacing and relative motion between the flippers was critical in governing these increases. The results of our analyses show that this phenomenon was probably present across the whole range of plesiosaur flipper motion and resolves the centuries-old debate about the propulsion style of these marine reptiles, as well as indicating why they retained two pairs of flippers for more than 100 million years. © 2017 The Author(s).

  6. Order enables efficient electron-hole separation at an organic heterojunction with a small energy loss

    KAUST Repository

    Menke, S. Matthew; Cheminal, Alexandre; Conaghan, Patrick; Ran, Niva A.; Greehnam, Neil C.; Bazan, Guillermo C.; Nguyen, Thuc-Quyen; Rao, Akshay; Friend, Richard H.

    2018-01-01

    Donor–acceptor organic solar cells often show low open-circuit voltages (VOC) relative to their optical energy gap (Eg) that limit power conversion efficiencies to ~12%. This energy loss is partly attributed to the offset between Eg and that of intermolecular charge transfer (CT) states at the donor–acceptor interface. Here we study charge generation occurring in PIPCP:PC61BM, a system with a very low driving energy for initial charge separation (Eg−ECT ~ 50 meV) and a high internal quantum efficiency (ηIQE ~ 80%). We track the strength of the electric field generated between the separating electron-hole pair by following the transient electroabsorption optical response, and find that while localised CT states are formed rapidly (<100 fs) after photoexcitation, free charges are not generated until 5 ps after photogeneration. In PIPCP:PC61BM, electronic disorder is low (Urbach energy <27 meV) and we consider that free charge separation is able to outcompete trap-assisted non-radiative recombination of the CT state.

  7. Energy efficiency analysis: biomass-to-wheel efficiency related with biofuels production, fuel distribution, and powertrain systems.

    Directory of Open Access Journals (Sweden)

    Wei-Dong Huang

    Full Text Available BACKGROUND: Energy efficiency analysis for different biomass-utilization scenarios would help make more informed decisions for developing future biomass-based transportation systems. Diverse biofuels produced from biomass include cellulosic ethanol, butanol, fatty acid ethyl esters, methane, hydrogen, methanol, dimethyether, Fischer-Tropsch diesel, and bioelectricity; the respective powertrain systems include internal combustion engine (ICE vehicles, hybrid electric vehicles based on gasoline or diesel ICEs, hydrogen fuel cell vehicles, sugar fuel cell vehicles (SFCV, and battery electric vehicles (BEV. METHODOLOGY/PRINCIPAL FINDINGS: We conducted a simple, straightforward, and transparent biomass-to-wheel (BTW analysis including three separate conversion elements--biomass-to-fuel conversion, fuel transport and distribution, and respective powertrain systems. BTW efficiency is a ratio of the kinetic energy of an automobile's wheels to the chemical energy of delivered biomass just before entering biorefineries. Up to 13 scenarios were analyzed and compared to a base line case--corn ethanol/ICE. This analysis suggests that BEV, whose electricity is generated from stationary fuel cells, and SFCV, based on a hydrogen fuel cell vehicle with an on-board sugar-to-hydrogen bioreformer, would have the highest BTW efficiencies, nearly four times that of ethanol-ICE. SIGNIFICANCE: In the long term, a small fraction of the annual US biomass (e.g., 7.1%, or 700 million tons of biomass would be sufficient to meet 100% of light-duty passenger vehicle fuel needs (i.e., 150 billion gallons of gasoline/ethanol per year, through up to four-fold enhanced BTW efficiencies by using SFCV or BEV. SFCV would have several advantages over BEV: much higher energy storage densities, faster refilling rates, better safety, and less environmental burdens.

  8. Energy Efficiency Analysis: Biomass-to-Wheel Efficiency Related with Biofuels Production, Fuel Distribution, and Powertrain Systems

    Science.gov (United States)

    Huang, Wei-Dong; Zhang, Y-H Percival

    2011-01-01

    Background Energy efficiency analysis for different biomass-utilization scenarios would help make more informed decisions for developing future biomass-based transportation systems. Diverse biofuels produced from biomass include cellulosic ethanol, butanol, fatty acid ethyl esters, methane, hydrogen, methanol, dimethyether, Fischer-Tropsch diesel, and bioelectricity; the respective powertrain systems include internal combustion engine (ICE) vehicles, hybrid electric vehicles based on gasoline or diesel ICEs, hydrogen fuel cell vehicles, sugar fuel cell vehicles (SFCV), and battery electric vehicles (BEV). Methodology/Principal Findings We conducted a simple, straightforward, and transparent biomass-to-wheel (BTW) analysis including three separate conversion elements -- biomass-to-fuel conversion, fuel transport and distribution, and respective powertrain systems. BTW efficiency is a ratio of the kinetic energy of an automobile's wheels to the chemical energy of delivered biomass just before entering biorefineries. Up to 13 scenarios were analyzed and compared to a base line case – corn ethanol/ICE. This analysis suggests that BEV, whose electricity is generated from stationary fuel cells, and SFCV, based on a hydrogen fuel cell vehicle with an on-board sugar-to-hydrogen bioreformer, would have the highest BTW efficiencies, nearly four times that of ethanol-ICE. Significance In the long term, a small fraction of the annual US biomass (e.g., 7.1%, or 700 million tons of biomass) would be sufficient to meet 100% of light-duty passenger vehicle fuel needs (i.e., 150 billion gallons of gasoline/ethanol per year), through up to four-fold enhanced BTW efficiencies by using SFCV or BEV. SFCV would have several advantages over BEV: much higher energy storage densities, faster refilling rates, better safety, and less environmental burdens. PMID:21765941

  9. Energy efficiency analysis: biomass-to-wheel efficiency related with biofuels production, fuel distribution, and powertrain systems.

    Science.gov (United States)

    Huang, Wei-Dong; Zhang, Y-H Percival

    2011-01-01

    Energy efficiency analysis for different biomass-utilization scenarios would help make more informed decisions for developing future biomass-based transportation systems. Diverse biofuels produced from biomass include cellulosic ethanol, butanol, fatty acid ethyl esters, methane, hydrogen, methanol, dimethyether, Fischer-Tropsch diesel, and bioelectricity; the respective powertrain systems include internal combustion engine (ICE) vehicles, hybrid electric vehicles based on gasoline or diesel ICEs, hydrogen fuel cell vehicles, sugar fuel cell vehicles (SFCV), and battery electric vehicles (BEV). We conducted a simple, straightforward, and transparent biomass-to-wheel (BTW) analysis including three separate conversion elements--biomass-to-fuel conversion, fuel transport and distribution, and respective powertrain systems. BTW efficiency is a ratio of the kinetic energy of an automobile's wheels to the chemical energy of delivered biomass just before entering biorefineries. Up to 13 scenarios were analyzed and compared to a base line case--corn ethanol/ICE. This analysis suggests that BEV, whose electricity is generated from stationary fuel cells, and SFCV, based on a hydrogen fuel cell vehicle with an on-board sugar-to-hydrogen bioreformer, would have the highest BTW efficiencies, nearly four times that of ethanol-ICE. In the long term, a small fraction of the annual US biomass (e.g., 7.1%, or 700 million tons of biomass) would be sufficient to meet 100% of light-duty passenger vehicle fuel needs (i.e., 150 billion gallons of gasoline/ethanol per year), through up to four-fold enhanced BTW efficiencies by using SFCV or BEV. SFCV would have several advantages over BEV: much higher energy storage densities, faster refilling rates, better safety, and less environmental burdens.

  10. Efficient and Scalable Fabrication of Solid Oxide Fuel Cells via 3D-Printing

    Data.gov (United States)

    National Aeronautics and Space Administration — Although solid oxide fuel cells (SOFCs) are a source of both efficient and clean electricity, the brittle ceramic materials which comprise them are difficult to form...

  11. CONTROLLING AS A MECHANISM TO INCREASE THE EFFICIENCY OF MANAGEMENT ENTERPRISES OF FUEL-ENERGY COMPLEX

    Directory of Open Access Journals (Sweden)

    M. A. Ostashkin

    2013-01-01

    Full Text Available This article discusses the possibility of application of controlling as mechanism of increasing the efficiency of management of enterprises of fuel- energy complex. The research was conducted on the materials of the JSC «Gazprom».

  12. Polymer Separators for High-Power, High-Efficiency Microbial Fuel Cells

    KAUST Repository

    Chen, Guang; Wei, Bin; Luo, Yong; Logan, Bruce E.; Hickner, Michael A.

    2012-01-01

    Microbial fuel cells (MFCs) with hydrophilic poly(vinyl alcohol) (PVA) separators showed higher Coulombic efficiencies (94%) and power densities (1220 mW m-2) than cells with porous glass fiber separators or reactors without a separator after 32

  13. Nanofiber-deposited porous platinum enables glucose fuel cell anodes with high current density in body fluids

    Science.gov (United States)

    Frei, Maxi; Erben, Johannes; Martin, Julian; Zengerle, Roland; Kerzenmacher, Sven

    2017-09-01

    The poisoning of platinum anodes by body-fluid constituents such as amino acids is currently the main hurdle preventing the application of abiotic glucose fuel cells as battery-independent power supply for medical implants. We present a novel anode material that enables continuous operation of glucose oxidation anodes in horse serum for at least 30 days at a current density of (7.2 ± 1.9) μA cm-2. The fabrication process is based on the electro-deposition of highly porous platinum onto a 3-dimensional carbon nanofiber support, leading to approximately 2-fold increased electrode roughness factors (up to 16500 ± 2300). The material's superior performance is not only related to its high specific surface area, but also to an improved catalytic activity and/or poisoning resistance. Presumably, this results from the micro- and nanostructure of the platinum deposits. This represents a major step forward in the development of implantable glucose fuel cells based on long-term stable platinum electrodes.

  14. Biofuels done right: land efficient animal feeds enable large environmental and energy benefits.

    Science.gov (United States)

    Dale, Bruce E; Bals, Bryan D; Kim, Seungdo; Eranki, Pragnya

    2010-11-15

    There is an intense ongoing debate regarding the potential scale of biofuel production without creating adverse effects on food supply. We explore the possibility of three land-efficient technologies for producing food (actually animal feed), including leaf protein concentrates, pretreated forages, and double crops to increase the total amount of plant biomass available for biofuels. Using less than 30% of total U.S. cropland, pasture, and range, 400 billion liters of ethanol can be produced annually without decreasing domestic food production or agricultural exports. This approach also reduces U.S. greenhouse gas emissions by 670 Tg CO₂-equivalent per year, or over 10% of total U.S. annual emissions, while increasing soil fertility and promoting biodiversity. Thus we can replace a large fraction of U.S. petroleum consumption without indirect land use change.

  15. Sulfur rich microporous polymer enables rapid and efficient removal of mercury(II) from water.

    Science.gov (United States)

    Xu, Dan; Wu, Winston Duo; Qi, Hao-Jun; Yang, Rui-Xia; Deng, Wei-Qiao

    2018-04-01

    Design and synthesis of adsorbents for efficient decontamination of hazardous contaminants Hg 2+ from wastewater, based on a facile and economical strategy, is an attractive target. Here, a novel sulfur rich microporous polymer (sulfur content of 31.4 wt %) with high surface area as well as densely populated sulfur atom with fast accessibility was reported to remove mercury (II) from water. The as prepared polymer (SMP) exhibited high binding affinity, high adsorption capacities, rapid adsorption kinetics, and good recyclability for Hg 2+ . The adsorption capacity of SMP was 595.2 mg g -1 . Furthermore, SMP could reduce trace concentrations of Hg 2+ from 200 p. p. b. to a level below drinking water standards (2 p. p. b.) within 3 min. This work allows large-scale production of sulfur rich porous materials for the practical application in water treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Final Scientific Report - "Improved Fuel Efficiency from Nanocomposite Tire Tread"

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Andrew Myers

    2005-12-30

    Rolling resistance, a measure of the energy lost as a tire rotates while moving, is a significant source of power and fuel loss. Recently, low rolling resistant tires have been formulated by adding silica to tire tread. These "Green Tires" (so named from the environmental advantages of lower emissions and improved fuel economy) have seen some commercial success in Europe, where high fuel prices and performance drive tire selection. Unfortunately, the higher costs of the silica and a more complicated manufacturing process have prevented significant commercialization - and the resulting fuel savings - in the U.S. In this project, TDA Research, Inc. (TDA) prepared an inexpensive alternative to silica that leads to tire components with lower rolling resistance. These new tire composite materials were processed with traditional rubber processing equipment. We prepared specially designed nanoparticle additives, based on a high purity, inorganic mineral whose surface can be easily modified for compatibility with tire tread formulations. Our nanocomposites decreased energy losses to hysteresis, the loss of energy from the compression and relaxation of an elastic material, by nearly 20% compared to a blank SBR sample. We also demonstrated better performance than a leading silica product, with easier production of our final rubber nanocomposite.

  17. Computational methods for more fuel-efficient ship

    NARCIS (Netherlands)

    Koren, B.

    2008-01-01

    The flow of water around a ship powered by a combustion engine is a key factor in the ship's fuel consumption. The simulation of flow patterns around ship hulls is therefore an important aspect of ship design. While lengthy computations are required for such simulations, research by Jeroen Wackers

  18. 75 FR 11806 - Notice of Public Meeting; Tire Fuel Efficiency

    Science.gov (United States)

    2010-03-12

    .... After the NPRM was issued, NHTSA conducted an internet survey to further explore what influences... CONTACT: Ms. Mary Versailles, Telephone: 1-202- 366-2057, Office of International Vehicle, Fuel Economy... proposed in the NPRM. After the NPRM was issued, NHTSA conducted an internet survey to further explore what...

  19. Extracting Fuel Efficiency Information From the Car Dashboard ...

    Indian Academy of Sciences (India)

    for one particular type of trip, say, city driving, long driving, hilly driving, congested ... to refer to the distance traveled by the car divided by volume of the fuel used to cover .... From now on, we must restrict our attention to interpolation curves. 2.

  20. Solution-processable MoOx nanocrystals enable highly efficient reflective and semitransparent polymer solar cells

    KAUST Repository

    Jagadamma, Lethy Krishnan

    2016-09-09

    Solution-manufacturing of organic solar cells with best-in-class power conversion efficiency (PCE) will require all layers to be solution-coated without compromising solar cell performance. To date, the hole transporting layer (HTL) deposited on top of the organic bulk heterojunction layer in the inverted architecture is most commonly an ultrathin (<10 nm) metal oxide layer prepared by vacuum-deposition. Here, we show that an alcohol-based nanocrystalline MoOx suspension with carefully controlled nanocrystal (NC) size can yield state of the art reflective and semitransparent solar cells. Using NCs smaller than the target HTL thickness (∼10 nm) can yield compact, pinhole-free films which result in highly efficient polymer:fullerene bulk heterojunction (BHJ) solar cells with PCE=9.5%. The solution processed HTL is shown to achieve performance parity with vacuum-evaporated HTLs for several polymer:fullerene combinations and is even shown to work as hole injection layer in polymer light emitting diodes (PLED). We also demonstrate that larger MoOx NCs (30–50 nm) successfully composite MoOx with Ag nanowires (NW) to form a highly conducting, transparent top anode with exceptional contact properties. This yields state-of-the-art semitransparent polymer: fullerene solar cells with PCE of 6.5% and overall transmission >30%. The remarkable performance of reflective and semitransparent OPVs is due to the uncommonly high fill factors achieved using a carefully designed strategy for implementation of MoOx nanocrystals as HTL materials. © 2016 Elsevier Ltd

  1. Auto-flotation of heterocyst enables the efficient production of renewable energy in cyanobacteria.

    Science.gov (United States)

    Chen, Ming; Li, Jihong; Zhang, Lei; Chang, Sandra; Liu, Chen; Wang, Jianlong; Li, Shizhong

    2014-02-06

    Utilizing cyanobacteria as a bioenergy resource is difficult due to the cost and energy consuming harvests of microalgal biomass. In this study, an auto-floating system was developed by increasing the photobiological H2 production in the heterocysts of filamentous cyanobacteria. An amount of 1.0 μM of diuron, which inhibited O2 production in cyanobacteria, resulted in a high rate of H2 production in heterocysts. The auto-floating process recovered 91.71% ± 1.22 of the accumulated microalgal biomass from the liquid media. Quantification analysis revealed that 0.72-1.10 μmol H2 per mg dry weight microalgal biomass was necessary to create this auto-floating system. Further bio-conversion by using anaerobic digestion converted the harvested microalgal biomass into biogas. Through this novel coupled system of photobiological H2 production and anaerobic digestion, a high level of light energy conversion efficiency from solar energy to bioenergy was attained with the values of 3.79% ± 0.76.

  2. Discovery of a super-strong promoter enables efficient production of heterologous proteins in cyanobacteria.

    Science.gov (United States)

    Zhou, Jie; Zhang, Haifeng; Meng, Hengkai; Zhu, Yan; Bao, Guanhui; Zhang, Yanping; Li, Yin; Ma, Yanhe

    2014-03-28

    Cyanobacteria are oxygenic photosynthetic prokaryotes that play important roles in the global carbon cycle. Recently, engineered cyanobacteria capable of producing various small molecules from CO2 have been developed. However, cyanobacteria are seldom considered as factories for producing proteins, mainly because of the lack of efficient strong promoters. Here, we report the discovery and verification of a super-strong promoter P(cpc560), which contains two predicted promoters and 14 predicted transcription factor binding sites (TFBSs). Using P(cpc560), functional proteins were produced at a level of up to 15% of total soluble protein in the cyanobacterium Synechocystis sp. 6803, a level comparable to that produced in Escherichia coli. We demonstrated that the presence of multiple TFBSs in P(cpc560) is crucial for its promoter strength. Genetically transformable cyanobacteria neither have endotoxins nor form inclusion bodies; therefore, P(cpc560) opens the possibility to use cyanobacteria as alternative hosts for producing heterogeneous proteins from CO2 and inorganic nutrients.

  3. Up-conversion nanoparticles sensitized inverse opal photonic crystals enable efficient water purification under NIR irradiation

    Science.gov (United States)

    Zhang, Yuanyuan; Wang, Lili; Ma, Xiumei; Ren, Junfeng; Sun, Qinxing; Shi, Yongsheng; Li, Lin; Shi, Jinsheng

    2018-03-01

    A novel porous monolayer inverse opal (IO) structure was prepared by a simple sol-gel method combined with a self-assembly PS photonic crystal (PC) as template. By prolonging deposition time of PS spheres, three-dimensional multilayer TiO2 IOPC was also fabricated. Up-conversion nanoparticles (UCNPs) were selected to sensitize TiO2 IOPCs. Photocatalytic activity of as-prepared materials was investigated by disinfection of bacteria and organic pollutant degradation. Under NIR light irradiation, a large improvement in bacterial inactivation and photodegradation efficiency could be seen for NYF/TiO2 composites in comparison with other samples. As for monolayer NYF/TiO2, water disinfection of 100% inactivation of bacteria is realized within 11 h and kinetic constant of RhB degradation is 0.133 h-1, which is about 10 times higher than that of pure TiO2 IOPCs. Reasons of enhanced photocatalytic activity were systematically investigated and a possible mechanism for NIR-driven photocatalysis was reasonably proposed.

  4. A New Superalloy Enabling Heavy Duty Gas Turbine Wheels for Improved Combined Cycle Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Detor, Andrew [General Electric Company, Niskayuna, NY (United States). GE Global Research; DiDomizio, Richard [General Electric Company, Niskayuna, NY (United States). GE Global Research; McAllister, Don [The Ohio State Univ., Columbus, OH (United States); Sampson, Erica [General Electric Company, Niskayuna, NY (United States). GE Global Research; Shi, Rongpei [The Ohio State Univ., Columbus, OH (United States); Zhou, Ning [General Electric Company, Niskayuna, NY (United States). GE Global Research

    2017-01-03

    The drive to increase combined cycle turbine efficiency from 62% to 65% for the next-generation advanced cycle requires a new heavy duty gas turbine wheel material capable of operating at 1200°F and above. Current wheel materials are limited by the stability of their major strengthening phase (gamma double prime), which coarsens at temperatures approaching 1200°F, resulting in a substantial reduction in strength. More advanced gamma prime superalloys, such as those used in jet engine turbine disks, are also not suitable due to size constraints; the gamma prime phase overages during the slow cooling rates inherent in processing thick-section turbine wheels. The current program addresses this need by screening two new alloy design concepts. The first concept exploits a gamma prime/gamma double prime coprecipitation reaction. Through manipulation of alloy chemistry, coprecipitation is controlled such that gamma double prime is used only to slow the growth of gamma prime during slow cooling, preventing over-aging, and allowing for subsequent heat treatment to maximize strength. In parallel, phase field modeling provides fundamental understanding of the coprecipitation reaction. The second concept uses oxide dispersion strengthening to improve on two existing alloys that exhibit excellent hold time fatigue crack growth resistance, but have insufficient strength to be considered for gas turbine wheels. Mechanical milling forces the dissolution of starting oxide powders into a metal matrix allowing for solid state precipitation of new, nanometer scale oxides that are effective at dispersion strengthening.

  5. Spectral-Efficiency - Illumination Pareto Front for Energy Harvesting Enabled VLC System

    KAUST Repository

    Abdelhady, Amr Mohamed Abdelaziz

    2017-12-13

    The continuous improvement in optical energy harvesting devices motivates visible light communication (VLC) system developers to utilize such available free energy sources. An outdoor VLC system is considered where an optical base station sends data to multiple users that are capable of harvesting the optical energy. The proposed VLC system serves multiple users using time division multiple access (TDMA) with unequal time and power allocation, which are allocated to improve the system performance. The adopted optical system provides users with illumination and data communication services. The outdoor optical design objective is to maximize the illumination, while the communication design objective is to maximize the spectral efficiency (SE). The design objectives are shown to be conflicting, therefore, a multiobjective optimization problem is formulated to obtain the Pareto front performance curve for the proposed system. To this end, the marginal optimization problems are solved first using low complexity algorithms. Then, based on the proposed algorithms, a low complexity algorithm is developed to obtain an inner bound of the Pareto front for the illumination-SE tradeoff. The inner bound for the Pareto-front is shown to be close to the optimal Pareto-frontier via several simulation scenarios for different system parameters.

  6. Emission Constrained Multiple-Pulse Fuel Injection Optimisation and Control for Fuel-Efficient Diesel Engines

    NARCIS (Netherlands)

    Luo, X.; Jager, B. de; Willems, F.P.T.

    2015-01-01

    With the application of multiple-pulse fuel injection profiles, the performance of diesel engines is enhanced in terms of low fuel consumption and low engine-out emission levels. However, the calibration effort increases due to a larger number of injection timing parameters. The difficulty of

  7. Solid-fuel cook stoves: Fuel efficiency and emissions testing--Austin

    Science.gov (United States)

    The World Health Organization estimates that approximately 1.6 million people prematurely die each year due to exposure to air pollutants from burning solid fuels for residential cooking and heating (WHO, 2010). Residential solid-fuel use accounts for approximately 25 percent of ...

  8. Emission constrained multiple-pulse fuel injection optimisation and control for fuel-efficient diesel engines

    NARCIS (Netherlands)

    Luo, X.; Jager, de A.G.; Willems, F.P.T.

    2015-01-01

    With the application of multiple-pulse fuel injec- tion profiles, the performance of diesel engines is enhanced in terms of low fuel consumption and low engine-out emission levels. However, the calibration effort increases due to a larger number of injection timing parameters. The difficulty of

  9. E85 and fuel efficiency: An empirical analysis of 2007 EPA test data

    International Nuclear Information System (INIS)

    Roberts, Matthew C.

    2008-01-01

    It is well known that ethanol has less energy per unit volume than gasoline. Differences in engine design and fuel characteristics affect the efficiency with which the chemical energy in gasoline and ethanol is converted into mechanical energy, so that the change in fuel economy may not be a linear function of energy content. This study analyzes the fuel economy tests performed by the US Environmental Protection Agency (EPA) on 2007 model year E85-compliant vehicles and finds that the difference in average fuel economy is not statistically different from the differential in energy content

  10. Possibility to Increase Biofuels Energy Efficiency used for Compression Ignition Engines Fueling

    Directory of Open Access Journals (Sweden)

    Calin D. Iclodean

    2014-02-01

    Full Text Available The paper presents the possibilities of optimizing the use of biofuels in terms of energy efficiency in compression ignition (CI engines fueling. Based on the experimental results was determinate the law of variation of the rate of heat released by the combustion process for diesel fuel and different blends of biodiesel. Using this law, were changed parameters of the engine management system (fuel injection law and was obtain increased engine performance (in terms of energy efficiency for use of different biofuel blends.

  11. Fort Lewis natural gas and fuel oil energy baseline and efficiency resource assessment

    International Nuclear Information System (INIS)

    Brodrick, J.R.; Daellenbach, K.K.; Parker, G.B.; Richman, E.E.; Secrest, T.J.; Shankle, S.A.

    1993-02-01

    The mission of the US Department of Energy (DOE) Federal Energy Management Program (FEMP) is to lead the improvement of energy efficiency and fuel flexibility within the federal sector. Through the Pacific Northwest Laboratory (PNL), FEMP is developing a fuel-neutral approach for identifying, evaluating, and acquiring all cost-effective energy projects at federal installations; this procedure is entitled the Federal Energy Decision Screening (FEDS) system. Through a cooperative program between FEMP and the Army Forces Command (FORSCOM) for providing technical assistance to FORSCOM installations, PNL has been working with the Fort Lewis Army installation to develop the FEDS procedure. The natural gas and fuel oil assessment contained in this report was preceded with an assessment of electric energy usage that was used to implement a cofunded program between Fort Lewis and Tacoma Public Utilities to improve the efficiency of the Fort's electric-energy-using systems. This report extends the assessment procedure to the systems using natural gas and fuel oil to provide a baseline of consumption and an estimate of the energy-efficiency potential that exists for these two fuel types at Fort Lewis. The baseline is essential to segment the end uses that are targets for broad-based efficiency improvement programs. The estimated fossil-fuel efficiency resources are estimates of the available quantities of conservation for natural gas, fuel oils number-sign 2 and number-sign 6, and fuel-switching opportunities by level of cost-effectiveness. The intent of the baseline and efficiency resource estimates is to identify the major efficiency resource opportunities and not to identify all possible opportunities; however, areas of additional opportunity are noted to encourage further effort

  12. The impact of interface bonding efficiency on high-burnup spent nuclear fuel dynamic performance

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Hao, E-mail: jiangh@ornl.gov; Wang, Jy-An John; Wang, Hong

    2016-12-01

    Highlights: • To investigate the impact of interfacial bonding efficiency at pellet-pellet and pellet-clad interfaces of high-burnup (HBU) spent nuclear fuel (SNF) on its dynamic performance. • Flexural rigidity, EI = M/κ, estimated from FEA results were benchmarked with SNF dynamic experimental results, and used to evaluate interface bonding efficiency. • Interface bonding efficiency can significantly dictate the SNF system rigidity and the associated dynamic performance. • With consideration of interface bonding efficiency and fuel cracking, HBU SNF fuel property was estimated with SNF static and dynamic experimental data. - Abstract: Finite element analysis (FEA) was used to investigate the impact of interfacial bonding efficiency at pellet-pellet and pellet-clad interfaces of high-burnup (HBU) spent nuclear fuel (SNF) on system dynamic performance. Bending moments M were applied to FEA model to evaluate the system responses. From bending curvature, κ, flexural rigidity EI can be estimated as EI = M/κ. The FEA simulation results were benchmarked with experimental results from cyclic integrated reversal bending fatigue test (CIRFT) of HBR fuel rods. The consequence of interface debonding between fuel pellets and cladding is a redistribution of the loads carried by the fuel pellets to the clad, which results in a reduction in composite rod system flexural rigidity. Therefore, the interface bonding efficiency at the pellet-pellet and pellet-clad interfaces can significantly dictate the SNF system dynamic performance. With the consideration of interface bonding efficiency, the HBU SNF fuel property was estimated with CIRFT test data.

  13. Increasing the electric efficiency of a fuel cell system by recirculating the anodic offgas

    Science.gov (United States)

    Heinzel, A.; Roes, J.; Brandt, H.

    The University of Duisburg-Essen and the Center for Fuel Cell Technology (ZBT Duisburg GmbH) have developed a compact multi-fuel steam reformer suitable for natural gas, propane and butane. Fuel processor prototypes based on this concept were built up in the power range from 2.5 to 12.5 kW thermal hydrogen power for different applications and different industrial partners. The fuel processor concept contains all the necessary elements, a prereformer step, a primary reformer, water gas shift reactors, a steam generator, internal heat exchangers, in order to achieve an optimised heat integration and an external burner for heat supply as well as a preferential oxidation step (PrOx) as CO purification. One of the built fuel processors is designed to deliver a thermal hydrogen power output of 2.5 kW according to a PEM fuel cell stack providing about 1 kW electrical power and achieves a thermal efficiency of about 75% (LHV basis after PrOx), while the CO content of the product gas is below 20 ppm. This steam reformer has been combined with a 1 kW PEM fuel cell. Recirculating the anodic offgas results in a significant efficiency increase for the fuel processor. The gross efficiency of the combined system was already clearly above 30% during the first tests. Further improvements are currently investigated and developed at the ZBT.

  14. Investigation into fuel pin reshuffling options in PWR in-core fuel management for enhancement of efficient use of nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    Daing, Aung Tharn, E-mail: atdaing@khu.ac.kr; Kim, Myung Hyun, E-mail: mhkim@khu.ac.kr

    2014-07-01

    Highlights: • This paper discusses an alternative option, fuel pin reshuffling for maximization of cycle energy production. • The prediction results of isotopic compositions of each burnt pin are verified. • The operating performance is analyzed at equilibrium core with fuel pin reshuffling. • The possibility of reuse of spent fuel pins for reduction of fresh fuel assemblies is investigated. - Abstract: An alternative way to enhance efficient use of nuclear fuel is investigated through fuel pin reshuffling options within PWR fuel assembly (FA). In modeling FA with reshuffled pins, as prerequisite, the single pin calculation method is proposed to estimate the isotopic compositions of each pin of burnt FA in the core-wide environment. Subsequently, such estimation has been verified by comparing with the neutronic performance of the reference design. Two scenarios are concerned, i.e., first scenario was targeted on the improvement of the uniform flux spatial distribution and on the enhancement of neutron economy by simply reshuffling the existing fuel pins in once-burnt fuel assemblies, and second one was focused on reduction of fresh fuel loading and discharged fuel assemblies with more economic incentives by reusing some available spent fuel pins still carrying enough reactivity that are mechanically sound ascertained. In scenario-1, the operating time was merely somewhat increased for few minutes when treating eight FAs by keeping enough safety margins. The scenario-2 was proved to reduce four fresh FAs loading without largely losing any targeted parameters from the safety aspect despite loss of 14 effective full power days for operation at reference plant full rated power.

  15. A Novel Technique that Enables Efficient Conduct of Simultaneous Isomerization and Fermentation (SIF) of Xylose

    Science.gov (United States)

    Rao, Kripa; Chelikani, Silpa; Relue, Patricia; Varanasi, Sasidhar

    Of the sugars recovered from lignocellulose, D-glucose can be readily converted into ethanol by baker's or brewer's yeast (Saccharomyces cerevisiae). However, xylose that is obtained by the hydrolysis of the hemicellulosic portion is not fermentable by the same species of yeasts. Xylose fermentation by native yeasts can be achieved via isomerization of xylose to its ketose isomer, xylulose. Isomerization with exogenous xylose isomerase (XI) occurs optimally at a pH of 7-8, whereas subsequent fermentation of xylulose to ethanol occurs at a pH of 4-5. We present a novel scheme for efficient isomerization of xylose to xylulose at conditions suitable for the fermentation by using an immobilized enzyme system capable of sustaining two different pH microenvironments in a single vessel. The proof-of-concept of the two-enzyme pellet is presented, showing conversion of xylose to xylulose even when the immobilized enzyme pellets are suspended in a bulk solution whose pH is sub-optimal for XI activity. The co-immobilized enzyme pellets may prove extremely valuable in effectively conducting "simultaneous isomerization and fermentation" (SIF) of xylose. To help further shift the equilibrium in favor of xylulose formation, sodium tetraborate (borax) was added to the isomerization solution. Binding of tetrahydroxyborate ions to xylulose effectively reduces the concentration of xylulose and leads to increased xylose isomerization. The formation of tetrahydroxyborate ions and the enhancement in xylulose production resulting from the complexation was studied at two different bulk pH values. The addition of 0.05 M borax to the isomerization solution containing our co-immobilized enzyme pellets resulted in xylose to xylulose conversion as high as 86% under pH conditions that are suboptimal for XI activity. These initial findings, which can be optimized for industrial conditions, have significant potential for increasing the yield of ethanol from xylose in an SIF approach.

  16. Steroids Regulate CXCL4 in the Human Endometrium During Menstruation to Enable Efficient Endometrial Repair.

    Science.gov (United States)

    Maybin, Jacqueline A; Thiruchelvam, Uma; Madhra, Mayank; Saunders, Philippa T K; Critchley, Hilary O D

    2017-06-01

    Repair of the endometrial surface at menstruation must be efficient to minimize blood loss and optimize reproductive function. The mechanism and regulation of endometrial repair remain undefined. To determine the presence/regulation of CXCL4 in the human endometrium as a putative repair factor at menses. Endometrial tissue was collected throughout the menstrual cycle from healthy women attending the gynecology department. Menstrual blood loss was objectively measured in a subset, and heavy menstrual bleeding (HMB) was defined as >80 mL per cycle. Monocytes were isolated from peripheral blood. CXCL4 messenger RNA (mRNA) and protein were identified by quantitative reverse transcription polymerase chain reaction and immunohistochemistry. The function/regulation of endometrial CXCL4 was explored by in vitro cell culture. CXCL4 mRNA concentrations were significantly increased during menstruation. Intense staining for CXCL4 was detected in late secretory and menstrual tissue, localized to stromal, epithelial and endothelial cells. Colocalization identified positive staining in CD68+ macrophages. Treatment of human endometrial stromal and endothelial cells (hESCs and HEECs, respectively) with steroids revealed differential regulation of CXCL4. Progesterone withdrawal resulted in significant increases in CXCL4 mRNA and protein in hESCs, whereas cortisol significantly increased CXCL4 in HEECs. In women with HMB, CXCL4 was reduced in endothelial cells during the menstrual phase compared with women with normal menstrual bleeding. Cortisol-exposed macrophages displayed increased chemotaxis toward CXCL4 compared with macrophages incubated with estrogen or progesterone. These data implicate CXCL4 in endometrial repair after menses. Reduced cortisol at the time of menses may contribute to delayed endometrial repair and HMB, in part by mechanisms involving aberrant expression of CXCL4. Copyright © 2017 by the Endocrine Society

  17. Optical signal processing for enabling high-speed, highly spectrally efficient and high capacity optical systems

    Science.gov (United States)

    Fazal, Muhammad Irfan

    The unabated demand for more capacity due to the ever-increasing internet traffic dictates that the boundaries of the state of the art maybe pushed to send more data through the network. Traditionally, this need has been satisfied by multiple wavelengths (wavelength division multiplexing), higher order modulation formats and coherent communication (either individually or combined together). WDM has the ability to reduce cost by using multiple channels within the same physical fiber, and with EDFA amplifiers, the need for O-E-O regenerators is eliminated. Moreover the availability of multiple colors allows for wavelength-based routing and network planning. Higher order modulation formats increases the capacity of the link by their ability to encode data in both the phase and amplitude of light, thereby increasing the bits/sec/Hz as compared to simple on-off keyed format. Coherent communications has also emerged as a primary means of transmitting and receiving optical data due to its support of formats that utilize both phase and amplitude to further increase the spectral efficiency of the optical channel, including quadrature amplitude modulation (QAM) and quadrature phase shift keying (QPSK). Polarization multiplexing of channels can double capacity by allowing two channels to share the same wavelength by propagating on orthogonal polarization axis and is easily supported in coherent systems where the polarization tracking can be performed in the digital domain. Furthermore, the forthcoming IEEE 100 Gbit/s Ethernet Standard, 802.3ba, provides greater bandwidth, higher data rates, and supports a mixture of modulation formats. In particular, Pol-MUX QPSK is increasingly becoming the industry's format of choice as the high spectral efficiency allows for 100 Gbit/s transmission while still occupying the current 50 GHz/channel allocation of current 10 Gbit/s OOK fiber systems. In this manner, 100 Gbit/s transfer speeds using current fiber links, amplifiers, and filters

  18. Cold homes, fuel poverty and energy efficiency improvements: A longitudinal focus group approach.

    Science.gov (United States)

    Grey, Charlotte N B; Schmieder-Gaite, Tina; Jiang, Shiyu; Nascimento, Christina; Poortinga, Wouter

    2017-08-01

    Cold homes and fuel poverty have been identified as factors in health and social inequalities that could be alleviated through energy efficiency interventions. Research on fuel poverty and the health impacts of affordable warmth initiatives have to date primarily been conducted using quantitative and statistical methods, limiting the way how fuel poverty is understood. This study took a longitudinal focus group approach that allowed exploration of lived experiences of fuel poverty before and after an energy efficiency intervention. Focus group discussions were held with residents from three low-income communities before (n = 28) and after (n = 22) they received energy efficiency measures funded through a government-led scheme. The results show that improving the energy efficiency of homes at risk of fuel poverty has a profound impact on wellbeing and quality of life, financial stress, thermal comfort, social interactions and indoor space use. However, the process of receiving the intervention was experienced by some as stressful. There is a need for better community engagement and communication to improve the benefits delivered by fuel poverty programmes, as well as further qualitative exploration to better understand the wider impacts of fuel poverty and policy-led intervention schemes.

  19. Interdependencies between transport fuel demand, efficiency and quality: An application to Austria

    International Nuclear Information System (INIS)

    Goerlich, Roland; Wirl, Franz

    2012-01-01

    This paper focuses on the interdependencies between technical efficiencies and energy demand which are often either treated in isolation or do not get the sufficient attention in the literature. More precisely, this paper uses technical efficiencies as one crucial determinant of energy demand in order to integrate at least two issues that are usually investigated separately from each other: the rebound effect resulting from improved technical efficiencies and the asymmetry of energy demand. In this regard, our paper sets out a theoretical framework which has the following implications: higher efficiency increases service demand (first order rebound), low fuel prices and higher efficiency increases the demand for quality (second order) which in turn increases service demand further (third order); ceteris paribus, energy price shocks should increase scrapping rates; fuel prices direct the R and D expenditures of car producers; those on engine efficiency are irreversible, which has the consequence that energy price elasticities depend on the history of energy prices rather than being asymmetrical. Derived implications are subsequently tested on Austrian data. In particular, the purchasing decision diesel versus gasoline powered cars allows to refute the myth that consumers apply high implicit rates for discounting the future benefit from efficient cars. - Research Highlights: ►Dependencies between efficiency, fuel price, quality and fuel demand are modelled. ►Austrian data supports model implications for the defined rounds of rebounds. ►R and D efforts are directed by fuel prices surpassing a threshold on large markets. ►Consumers apply low implicit discount rates for future benefits from efficient cars. ►Effects of policy instruments (fuel efficiency standard, taxes, etc.) are discussed.

  20. Alternative Fuel and Advanced Technology Commercial Lawn Equipment (Spanish version); Clean Cities, Energy Efficiency & Renewable Energy (EERE)

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, Erik

    2015-06-01

    Powering commercial lawn equipment with alternative fuels or advanced engine technology is an effective way to reduce U.S. dependence on petroleum, reduce harmful emissions, and lessen the environmental impacts of commercial lawn mowing. Numerous alternative fuel and fuel-efficient advanced technology mowers are available. Owners turn to these mowers because they may save on fuel and maintenance costs, extend mower life, reduce fuel spillage and fuel theft, and demonstrate their commitment to sustainability.

  1. Last Mile Towards Efficient Healthcare Delivery in Switzerland: eHealth Enabled Applications Could Speed Up the Care Process.

    Science.gov (United States)

    Deng, Yihan; Bürkle, Thomas; Holm, Jürgen; Zetz, Erwin; Denecke, Kerstin

    2018-01-01

    A precise and timely care delivery depends on an efficient triage performed by primary care providers and smooth collaboration with other medical specialities. In recent years telemedicine gained increasing importance for efficient care delivery. It's use, however, has been limited by legal issues, missing digital infrastructures, restricted support from health insurances and the digital divide in the population. A new era towards eHealth and telemedicine starts with the establishment of national eHealth regulations and laws. In Switzerland, a nation-wide digital infrastructure and electronic health record will be established. But appropriate healthcare apps to improve patient care based on this infrastructure remain rare. In this paper, we present two applications (self-anamnesis and eMedication assistant) for eHealth enabled care delivery which have the potential to speed up diagnosis and treatment.

  2. Changing the Culture of Fuel Efficiency: A Change in Attitude

    Science.gov (United States)

    2014-05-09

    B. (2006, January-February Volume 40, Number 1). Cultura Organizacional em Organizacoes Publicas no Brasil . RAP, pp. 81-105. Ray, K. W., & Goppelt...see a zero sloped trend with a y -intercept of 100. This would indicate that the data set has a normal distribution, and the equation appropriately...Figure 7: Pilot Efficiency Score versus Takeoff Weight Graph Figure 8: Pilot Efficiency Score versus Total Flight Time Graph y = -6E-05x

  3. 1366 Project Automate: Enabling Automation for <$0.10/W High-Efficiency Kerfless Wafers Manufactured in the US

    Energy Technology Data Exchange (ETDEWEB)

    Lorenz, Adam [1366 Technologies, Bedford, MA (United States)

    2017-05-10

    For photovoltaic (PV) manufacturing to thrive in the U.S., there must be an innovative core to the technology. Project Automate builds on 1366’s proprietary Direct Wafer® kerfless wafer technology and aims to unlock the cost and efficiency advantages of thin kerfless wafers. Direct Wafer is an innovative, U.S.-friendly (efficient, low-labor content) manufacturing process that addresses the main cost barrier limiting silicon PV cost-reductions – the 35-year-old grand challenge of manufacturing quality wafers (40% of the cost of modules) without the cost and waste of sawing. This simple, scalable process will allow 1366 to manufacture “drop-in” replacement wafers for the $10 billion silicon PV wafer market at 50% of the cost, 60% of the capital, and 30% of the electricity of conventional casting and sawing manufacturing processes. This SolarMat project developed the Direct Wafer processes’ unique capability to tailor the shape of wafers to simultaneously make thinner AND stronger wafers (with lower silicon usage) that enable high-efficiency cell architectures. By producing wafers with a unique target geometry including a thick border (which determines handling characteristics) and thin interior regions (which control light capture and electron transport and therefore determine efficiency), 1366 can simultaneously improve quality and lower cost (using less silicon).

  4. Novel Materials for High Efficiency Direct Methanol Fuel Cells

    Energy Technology Data Exchange (ETDEWEB)

    Carson, Stephen [Arkema Inc.; Mountz, David [Arkema Inc.; He, Wensheng [Arkema Inc.; Zhang, Tao [Arkema Inc.

    2013-12-31

    Direct methanol fuel cell membranes were developed using blends of different polyelectrolytes with PVDF. The membranes showed complex relationships between polyelectrolyte chemistry, morphology, and processing. Although the PVDF grade was found to have little effect on the membrane permselectivity, it does impact membrane conductivity and methanol permeation values. Other factors, such as varying the polyelectrolyte polarity, using varying crosslinking agents, and adjusting the equivalent weight of the membranes impacted methanol permeation, permselectivity, and areal resistance. We now understand, within the scope of the project work completed, how these inter-related performance properties can be tailored to achieve a balance of performance.

  5. Polymer electrolyte fuel cells: flow field for efficient air operation

    Energy Technology Data Exchange (ETDEWEB)

    Buechi, F N; Tsukada, A; Haas, O; Scherer, G G [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1997-06-01

    A new flow field was designed for a polymer electrolyte fuel cell stack with an active area of 200 cm{sup 2} for operation at low air stoichiometry and low air over pressure. Optimum of gas flow and channel dimensions were calculated based on the required pressure drop in the fluid. Single cells and a bi-cell stack with the new flow field show an improved current/voltage characteristic when operated at low air stoichiometries as compared to that of the previous non optimized design. (author) 4 figs., 3 refs.

  6. Enabling renewable energy and energy efficiency technologies. Opportunities in Eastern Europe, Caucasus, Central Asia, Southern and Eastern Mediterranean

    Energy Technology Data Exchange (ETDEWEB)

    Barnsley, Ingrid; Blank, Amanda; Brown, Adam

    2015-06-01

    The increased deployment of renewable energy and energy efficiency technologies (RE&EET) in the South Eastern Mediterranean (SEMED) region and in the Early Transition Countries (ETC) could bring a host of benefits, including enhanced energy security, increased national revenues and environmental gains. A new IEA Insights paper considers policy options for supporting the deployment of RE&EET, as well as the surrounding factors that can enable – or indeed impede – the successful implementation of such support policies in both regions. Drawing on a wealth of IEA analyses and policy experiences globally, the paper: provides a summary of the energy profiles of the ETC and SEMED regions; highlights overarching, ''enabling'' factors that can help to set the necessary foundations for the successful implementation of policy to support RE&EET deployment; analyses policy options for both RE and EE, drawing on practical examples and highlighting indicative policies that correspond with varying levels of market maturity; and provides a checklist for assessing the level of supportiveness of national policy frameworks for RE&EET. The paper concludes by pointing to the significant potential for energy efficiency and renewable energy gains in both regions.

  7. Development of Nano-crystalline Doped-Ceramic Enabled Fiber Sensors for High Temperature In-Situ Monitoring of Fossil Fuel Gases

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Hai [Missouri Univ. of Science and Technology, Rolla, MO (United States); Dong, Junhang [Univ. of Cincinnati, OH (United States); Lin, Jerry [Arizona State Univ., Tempe, AZ (United States); Romero, Van [New Mexico Institute of Mining and Technology, Socorro, NM (United States)

    2012-03-01

    This is a final technical report for the first project year from July 1, 2005 to Jan 31, 2012 for DoE/NETL funded project DE-FC26-05NT42439: Development of Nanocrystalline Doped-Ceramic Enabled Fiber Sensors for High Temperature In-Situ Monitoring of Fossil Fuel Gases. This report summarizes the technical progresses and achievements towards the development of novel nanocrystalline doped ceramic material-enabled optical fiber sensors for in situ and real time monitoring the gas composition of flue or hot gas streams involved in fossil-fuel based power generation and hydrogen production.

  8. Maximizing Efficiency in Two-step Solar-thermochemical Fuel Production

    Energy Technology Data Exchange (ETDEWEB)

    Ermanoski, I. [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States)

    2015-05-01

    Widespread solar fuel production depends on its economic viability, largely driven by the solar-to-fuel conversion efficiency. In this paper, the material and energy requirements in two-step solar-thermochemical cycles are considered.The need for advanced redox active materials is demonstrated, by considering the oxide mass flow requirements at a large scale. Two approaches are also identified for maximizing the efficiency: optimizing reaction temperatures, and minimizing the pressure in the thermal reduction step by staged thermal reduction. The results show that each approach individually, and especially the two in conjunction, result in significant efficiency gains.

  9. Residential carbon dioxide emissions in Canada. Impact of efficiency improvements and fuel substitution

    International Nuclear Information System (INIS)

    Ugursal, V.I.; FUng, A.S.

    1998-01-01

    The effect of improving house envelope, heating system and appliance efficiencies, and fuel substitution on the atmospheric emissions of carbon dioxide in the Canadian residential sector is studied based on simulation studies. The findings clearly indicate that improving appliance efficiency reduces the overall end-use energy consumption in the residential sector as well as the associated carbon dioxide emissions. However, the magnitude of the reduction in carbon dioxide emissions as a result of improving only appliance efficiencies is quite small. Significantly larger reductions can be obtained by improving house envelopes and heating/cooling systems in addition to improving appliance efficiencies. Fuel substitution for space and domestic hot water heating can also present a potential to reduce carbon dioxide emissions depending on the fuel substitution scenario adopted. (author)

  10. Study of the Platooning Fuel Efficiency under ETSI ITS-G5 Communications

    NARCIS (Netherlands)

    Lyamin, N.; Deng, Q.; Vinel, A

    2016-01-01

    In this paper we evaluate the performance of platoon enabled by contemporary ITS-G5 vehicular communications through the number of simulation experiments. We assess platooning fuel consumption performance under two communication setups and estimate the potential influence of the communication system

  11. 76 FR 57105 - Greenhouse Gas Emissions Standards and Fuel Efficiency Standards for Medium- and Heavy-Duty...

    Science.gov (United States)

    2011-09-15

    ... CFR Parts 523, 534, and 535 Greenhouse Gas Emissions Standards and Fuel Efficiency Standards for...-2010-0079; FRL-9455-1] RIN 2060-AP61; 2127-AK74 Greenhouse Gas Emissions Standards and Fuel Efficiency... Heavy-Duty National Program that will reduce greenhouse gas emissions and fuel consumption for on-road...

  12. Barriers to efficiency improvement and fuel switching in Karnataka, India

    International Nuclear Information System (INIS)

    Reddy, A.

    1991-01-01

    Implementing energy efficiency changes requires a wide range measures. Improvements, therefore, require actions at the lowest level of the consumer, through the highest level of the global agencies. Due to the multiplicity of participants, however, barriers to achieving these improvements can arise at every level. The major barriers to improving energy efficiency in developing countries are defined and paths to overcome these challenges are identified. Topics of discussion include: energy consumers; end-use equipment manufacturers; end-use equipment providers; energy carrier producers and distributors; actual/potential cogenerators; financial institutions; government; and international, multilateral and industrialized country funding/aid agencies

  13. Vehicle Fuel-Efficiency Choices, Emission Externalities, and Urban Sprawl

    DEFF Research Database (Denmark)

    Kim, Jinwon

    This paper shows that the city where both congestion externalities and externalities from greenhouse gas emissions are corrected by efficient policies is more compact than the laissez-faire equilibrium city. Motivated by recent empirical studies showing a positive relationship between population...

  14. Scaling of the burning efficiency for multicomponent fuel pool fires

    DEFF Research Database (Denmark)

    van Gelderen, Laurens; Farahani, Hamed Farmahini; Rangwala, Ali S.

    In order to improve the validity of small scale crude oil burning experiments, which seem to underestimate the burning efficiency obtained in larger scales, the gasification mechanism of crude oil was studied. Gasification models obtained from literature were used to make a set of predictions for...... an external heat source to simulate the larger fire size are currently in process....

  15. Efficient Fuel Pretreatment: Simultaneous Torrefaction and Grinding of Biomass

    DEFF Research Database (Denmark)

    Saleh, Suriyati Binti; Hansen, Brian Brun; Jensen, Peter Arendt

    2013-01-01

    Combining torrefaction and grinding of biomass in one reactor may be an attractive fuel pretreatment process. A combined laboratory torrefaction and ball mill reactor has been constructed for studies of the influence of temperature and residence time on the product yields and particle size...... reductions of Danish wheat straw, spruce chips, and pine chips. On the basis of initial experiments, which evaluated the influence of reactor mass loading, gas flow, and grinding ball size and material, a standard experimental procedure was developed. The particle size reduction capability......, and ash composition, where straw has a higher alkali content. This and other studies indicate that the large difference in the alkali contents of the biomasses is the main cause for the observed difference in torrefaction characteristics. Experiments with separate particle heating and grinding showed...

  16. Polycistronic tRNA and CRISPR guide-RNA enables highly efficient multiplexed genome engineering in human cells.

    Science.gov (United States)

    Dong, Fengping; Xie, Kabin; Chen, Yueying; Yang, Yinong; Mao, Yingwei

    2017-01-22

    CRISPR/Cas9 has been widely used for genomic editing in many organisms. Many human diseases are caused by multiple mutations. The CRISPR/Cas9 system provides a potential tool to introduce multiple mutations in a genome. To mimic complicated genomic variants in human diseases, such as multiple gene deletions or mutations, two or more small guide RNAs (sgRNAs) need to be introduced all together. This can be achieved by separate Pol III promoters in a construct. However, limited enzyme sites and increased insertion size lower the efficiency to make a construct. Here, we report a strategy to quickly assembly multiple sgRNAs in one construct using a polycistronic-tRNA-gRNA (PTG) strategy. Taking advantage of the endogenous tRNA processing system in mammalian cells, we efficiently express multiple sgRNAs driven using only one Pol III promoter. Using an all-in-one construct carrying PTG, we disrupt the deacetylase domain in multiple histone deacetylases (HDACs) in human cells simultaneously. We demonstrate that multiple HDAC deletions significantly affect the activation of the Wnt-signaling pathway. Thus, this method enables to efficiently target multiple genes and provide a useful tool to establish mutated cells mimicking human diseases. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Synthetic Klebsiella pneumoniae-Shewanella oneidensis Consortium Enables Glycerol-Fed High-Performance Microbial Fuel Cells.

    Science.gov (United States)

    Li, Feng; Yin, Changji; Sun, Liming; Li, Yuanxiu; Guo, Xuewu; Song, Hao

    2018-05-01

    Microbial fuel cell (MFC) is an eco-friendly bio-electrochemical sys-tem that uses microorganism as biocatalyst to convert biomass into electricity. Glycerol, as a waste in the biodiesel refinery processes, is an appealing substrate for MFC. Nevertheless, glycerol cannot be utilized as carbon source by well-known exoelectrogens such as Shewanella oneidensis. Herein, to generate electricity by rapidly harnessing glycerol, the authors rationally constructed a Klebsiella pneumoniae-Shewanella oneidensis microbial consortium to efficiently harvest electricity from glyc-erol, in which K. pneumoniae converted glycerol into lactate, fed to S. oneidensis as carbon source and electron donor. To improve electricity output, the authors systematically engineered the consortium in terms of carbon flux distribution and efficiency of extracellular electron transfer (EET). To direct more carbon flux to lactate biosynthesis in K. pneumoniae, the authors eliminated the ethanol pathway by knocking out the alcohol dehydrogenase gene (adhE), and enhanced lactate biosynthesis by heterologously expressing a lactate dehydrogen-ase gene (ldhD) from Lactobacillus bulgaricus and a lactate transporter gene (lldP) from Escherichia coli. To facilitate EET between S. oneidensis and anode surfaces, a biosynthetic flavins pathway from Bacillus subtilis is introduced into S. oneidensis. The author further optimized the glycerol concentration, thus S. oneidensis could be continuously fed with lactate synthesized from K. pneumoniae at a constant rate. Our glycerol-fed MFC generated a maximum power density of 19.9 mW/m 2 , significantly higher than that of the wild-type consor-tium. This work suggested that engineering microbial consortia is an effi-cient strategy to expand the spectrum of usable carbon sources and promote electricity power production in MFCs. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Solar fuel processing efficiency for ceria redox cycling using alternative oxygen partial pressure reduction methods

    International Nuclear Information System (INIS)

    Lin, Meng; Haussener, Sophia

    2015-01-01

    Solar-driven non-stoichiometric thermochemical redox cycling of ceria for the conversion of solar energy into fuels shows promise in achieving high solar-to-fuel efficiency. This efficiency is significantly affected by the operating conditions, e.g. redox temperatures, reduction and oxidation pressures, solar irradiation concentration, or heat recovery effectiveness. We present a thermodynamic analysis of five redox cycle designs to investigate the effects of working conditions on the fuel production. We focused on the influence of approaches to reduce the partial pressure of oxygen in the reduction step, namely by mechanical approaches (sweep gassing or vacuum pumping), chemical approaches (chemical scavenger), and combinations thereof. The results indicated that the sweep gas schemes work more efficient at non-isothermal than isothermal conditions, and efficient gas phase heat recovery and sweep gas recycling was important to ensure efficient fuel processing. The vacuum pump scheme achieved best efficiencies at isothermal conditions, and at non-isothermal conditions heat recovery was less essential. The use of oxygen scavengers combined with sweep gas and vacuum pump schemes further increased the system efficiency. The present work can be used to predict the performance of solar-driven non-stoichiometric redox cycles and further offers quantifiable guidelines for system design and operation. - Highlights: • A thermodynamic analysis was conducted for ceria-based thermochemical cycles. • Five novel cycle designs and various operating conditions were proposed and investigated. • Pressure reduction method affects optimal operating conditions for maximized efficiency. • Chemical oxygen scavenger proves to be promising in further increasing efficiency. • Formulation of quantifiable design guidelines for economical competitive solar fuel processing

  19. Efficient running of steam generator trims fuel cost

    International Nuclear Information System (INIS)

    Selim, M.; Eltouny, S.A.

    1993-01-01

    E scaling energy prices have led to drastic changes in the operating philosophy of the worldwide industry. About 50% of the thermal energy in industry is being consumed in steam boilers. The new energy reduction programs that have been adopted in egypt draw attention to the boilers, not only to trim energy consumption and improve the production of steam but also to save as much money as possible in doing it. Organization for energy planning (OEP) has started a program for 'Boiler efficiency improvement' in industry since 2 years. The program aimed at performing energy audits in a selective number of industries in both public and private sectors using fire tube boilers produced locally by El Nasr company. As a result of audits an evaluation of performance of this type of boilers was,performed. The energy profiles and the common problems affecting the efficiency of boilers were determined. Energy conservation opportunities (ECO) were identified. 9 figs

  20. Combustion Mode Design with High Efficiency and Low Emissions Controlled by Mixtures Stratification and Fuel Reactivity

    Directory of Open Access Journals (Sweden)

    Hu eWang

    2015-08-01

    Full Text Available This paper presents a review on the combustion mode design with high efficiency and low emissions controlled by fuel reactivity and mixture stratification that have been conducted in the authors’ group, including the charge reactivity controlled homogeneous charge compression ignition (HCCI combustion, stratification controlled premixed charge compression ignition (PCCI combustion, and dual-fuel combustion concepts controlled by both fuel reactivity and mixture stratification. The review starts with the charge reactivity controlled HCCI combustion, and the works on HCCI fuelled with both high cetane number fuels, such as DME and n-heptane, and high octane number fuels, such as methanol, natural gas, gasoline and mixtures of gasoline/alcohols, are reviewed and discussed. Since single fuel cannot meet the reactivity requirements under different loads to control the combustion process, the studies related to concentration stratification and dual-fuel charge reactivity controlled HCCI combustion are then presented, which have been shown to have the potential to achieve effective combustion control. The efforts of using both mixture and thermal stratifications to achieve the auto-ignition and combustion control are also discussed. Thereafter, both charge reactivity and mixture stratification are then applied to control the combustion process. The potential and capability of thermal-atmosphere controlled compound combustion mode and dual-fuel reactivity controlled compression ignition (RCCI/highly premixed charge combustion (HPCC mode to achieve clean and high efficiency combustion are then presented and discussed. Based on these results and discussions, combustion mode design with high efficiency and low emissions controlled by fuel reactivity and mixtures stratification in the whole operating range is proposed.

  1. BWR Spent Nuclear Fuel Interfacial Bonding Efficiency Study

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jy-An John [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jiang, Hao [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-04-30

    The objective of this project is to perform a systematic study of spent nuclear fuel (SNF, also known as “used nuclear fuel” [UNF]) integrity under simulated transportation environments using the Cyclic Integrated Reversible-Bending Fatigue Tester (CIRFT) hot-cell testing technology developed at Oak Ridge National Laboratory (ORNL) in August 2013. Under Nuclear Regulatory Commission (NRC) sponsorship, ORNL completed four benchmark tests, four static tests, and twelve dynamic or cycle tests on H. B. Robinson (HBR) high burn-up (HBU) fuel. The clad of the HBR fuels was made of Zircaloy-4. Testing was continued in fiscal year (FY) 2014 using Department of Energy (DOE) funds. Additional CIRFT testing was conducted on three HBR rods; two specimens failed, and one specimen was tested to over 2.23 × 107 cycles without failing. The data analysis on all the HBR SNF rods demonstrated that it is necessary to characterize the fatigue life of the SNF rods in terms of (1) the curvature amplitude and (2) the maximum absolute of curvature extremes. The maximum extremes are significant because they signify the maximum tensile stress for the outer fiber of the bending rod. CIRFT testing has also addressed a large variation in hydrogen content on the HBR rods. While the load amplitude is the dominant factor that controls the fatigue life of bending rods, the hydrogen content also has an important effect on the lifetime attained at each load range tested. In FY 15, eleven SNF rod segments from the Limerick BWR were tested using the ORNL CIRFT equipment; one test under static conditions and ten tests under dynamic loading conditions. Under static unidirectional loading, a moment of 85 N·m was obtained at a maximum curvature of 4.0 m-1. The specimen did not show any sign of failure during three repeated loading cycles to a similar maximum curvature. Ten cyclic tests were conducted with amplitudes varying from 15.2 to 7.1 N·m. Failure was observed in nine of

  2. An efficient mathematical model for air-breathing PEM fuel cells

    International Nuclear Information System (INIS)

    Ismail, M.S.; Ingham, D.B.; Hughes, K.J.; Ma, L.; Pourkashanian, M.

    2014-01-01

    Graphical abstract: The effects of the ambient humidity on the performance of air-breathing PEM fuel cells become more pronounced as the ambient temperature increases. The polarisation curves have been generated using the in-house developed MATLAB® application, Polarisation Curve Generator, which is available in the supplementary data. - Highlights: • An efficient mathematical model has been developed for an air-breathing PEM fuel cell. • The fuel cell performance is significantly over-predicted if the Joule and entropic heats are neglected. • The fuel cell performance is highly sensitive to the state of water at the thermodynamic equilibrium. • The cell potential dictates the favourable ambient conditions for the fuel cell. - Abstract: A simple and efficient mathematical model for air-breathing proton exchange membrane (PEM) fuel cells has been built. One of the major objectives of this study is to investigate the effects of the Joule and entropic heat sources, which are often neglected, on the performance of air-breathing PEM fuel cells. It is found that the fuel cell performance is significantly over-predicted if one or both of these heat sources is not incorporated into the model. Also, it is found that the performance of the fuel cell is highly sensitive to the state of the water at the thermodynamic equilibrium magnitude as both the entropic heat and the Nernst potential considerably increase if water is assumed to be produced in liquid form rather than in vapour form. Further, the heat of condensation is shown to be small and therefore, under single-phase modelling, has a negligible effect on the performance of the fuel cell. Finally, the favourable ambient conditions depend on the operating cell potential. At intermediate cell potentials, a mild ambient temperature and low humidity are favoured to maintain high membrane conductivity and mitigate water flooding. At low cell potentials, low ambient temperature and high humidity are favoured to

  3. Impact of inlet fogging and fuels on power and efficiency of gas turbine plants

    Directory of Open Access Journals (Sweden)

    Basha Mehaboob

    2013-01-01

    Full Text Available A computational study to assess the performance of different gas turbine power plant configurations is presented in this paper. The work includes the effect of humidity, ambient inlet air temperature and types of fuels on gas turbine plant configurations with and without fogger unit. Investigation also covers economic analysis and effect of fuels on emissions. GT frames of various sizes/ratings are being used in gas turbine power plants in Saudi Arabia. 20 MWe GE 5271RA, 40 MWe GE-6561B and 70 MWe GE-6101FA frames are selected for the present study. Fogger units with maximum mass flow rate of 2 kg/s are considered for the present analysis. Reverse Osmosis unit of capacity 4 kg/s supplies required water to the fogger units. GT PRO software has been used for carrying out the analysis including; net plant output and net efficiency, break even electricity price and break even fuel LHV price etc., for a given location of Saudi Arabia. The relative humidity and temperature have been varied from 30 to 45 % and from 80 to 100° F, respectively. Fuels considered in the study are natural gas, diesel and heavy bunker oil. Simulated gas turbine plant output from GT PRO has been validated against an existing gas turbine plant output. It has been observed that the simulated plant output is less than the existing gas turbine plant output by 5%. Results show that variation of humidity does not affect the gas turbine performance appreciably for all types of fuels. For a decrease of inlet air temperature by 10 °F, net plant output and efficiency have been found to increase by 5 and 2 %, respectively for all fuels, for GT only situation. However, for GT with Fogger scenario, for a decrease of inlet air temperature by 10 °F, net plant output and efficiency have been found to further increase by 3.2 and 1.2 %, respectively for all fuels. For all GT frames with fogger, the net plant output and efficiency are relatively higher as compared to GT only case for all

  4. Energy analysis of an original steering technology that saves fuel and boosts efficiency

    International Nuclear Information System (INIS)

    Daher, Naseem; Ivantysynova, Monika

    2014-01-01

    Highlights: • A novel energy-saving steer-by-wire technology is introduced, dubbed “DC SbW”. • A prototype vehicle is retrofitted with “DC SbW” and tested for overall efficiency. • Energy analysis is conducted to compare “DC SbW” against state-of-the-art. • “DC SbW” achieves more work while consuming less fuel → higher efficiency. - Abstract: Stemmed by ever-increasing demand on fossil fuels and increased environmental awareness to reduce carbon emissions, improving the efficiency of components and systems has been receiving paramount attention in most industries during the past few years. This is especially true in the mobile machinery industry, which produces high power equipment with relatively low energy efficiency for the most part. Mobile machines strictly employ fluid power systems owing to the superlative power density of hydraulic components. Nevertheless, no major breakthrough technologies to significantly boost the efficiency of fluid power systems have emerged, except for the recent development of a throttle-less actuation technology, known as pump displacement control (DC), which has been proven to be an energy efficient alternative and a serious contender to state-of-the-art technologies. This paper deals with analyzing the energy efficiency of a DC steering system versus a more conventional valve controlled counterpart, which conveys how effectively the two systems convert the chemical energy stored in the diesel fuel into useful mechanical energy. Experimental testing on a prototype test vehicle showed that DC steering results in 14.5% fuel savings, 22.6% productivity gain, and a grand total of 43.5% fuel usage efficiency increase

  5. Co-production of acetone and ethanol with molar ratio control enables production of improved gasoline or jet fuel blends.

    Science.gov (United States)

    Baer, Zachary C; Bormann, Sebastian; Sreekumar, Sanil; Grippo, Adam; Toste, F Dean; Blanch, Harvey W; Clark, Douglas S

    2016-10-01

    The fermentation of simple sugars to ethanol has been the most successful biofuel process to displace fossil fuel consumption worldwide thus far. However, the physical properties of ethanol and automotive components limit its application in most cases to 10-15 vol% blends with conventional gasoline. Fermentative co-production of ethanol and acetone coupled with a catalytic alkylation reaction could enable the production of gasoline blendstocks enriched in higher-chain oxygenates. Here we demonstrate a synthetic pathway for the production of acetone through the mevalonate precursor hydroxymethylglutaryl-CoA. Expression of this pathway in various strains of Escherichia coli resulted in the co-production of acetone and ethanol. Metabolic engineering and control of the environmental conditions for microbial growth resulted in controllable acetone and ethanol production with ethanol:acetone molar ratios ranging from 0.7:1 to 10.0:1. Specifically, use of gluconic acid as a substrate increased production of acetone and balanced the redox state of the system, predictively reducing the molar ethanol:acetone ratio. Increases in ethanol production and the molar ethanol:acetone ratio were achieved by co-expression of the aldehyde/alcohol dehydrogenase (AdhE) from E. coli MG1655 and by co-expression of pyruvate decarboxylase (Pdc) and alcohol dehydrogenase (AdhB) from Z. mobilis. Controlling the fermentation aeration rate and pH in a bioreactor raised the acetone titer to 5.1 g L(-1) , similar to that obtained with wild-type Clostridium acetobutylicum. Optimizing the metabolic pathway, the selection of host strain, and the physiological conditions employed for host growth together improved acetone titers over 35-fold (0.14-5.1 g/L). Finally, chemical catalysis was used to upgrade the co-produced ethanol and acetone at both low and high molar ratios to higher-chain oxygenates for gasoline and jet fuel applications. Biotechnol. Bioeng. 2016;113: 2079-2087. © 2016 Wiley

  6. The Fuel Efficiency of Maritime Transport. Potential for improvement and analysis of barriers

    Energy Technology Data Exchange (ETDEWEB)

    Faber, J.; Nelissen, D.; Smit, M. [CE Delft, Delft (Netherlands); Behrends, B. [Marena Ltd., s.l. (United Kingdom); Lee, D.S. [Manchester Metropolitan University, Machester (United Kingdom)

    2012-02-15

    There is significant potential to improve the fuel efficiency of ships and thus contribute to reducing greenhouse gas emissions from maritime transport. It has long been recognised that this potential is not being fully exploited, owing to the existence of non-market barriers. This report analyses the barriers to implementing fuel efficiency improvements, and concludes that the most important of these are the split incentive between ship owners and operators, a lack of trusted data on new technologies, and transaction costs associated with evaluating measures. As a result, in practice about a quarter of the cost-effective abatement potential is unavailable. There are several ways to overcome these barriers. The split incentive can - to some extent - be overcome by providing more detailed information on the fuel efficiency of vessels, making due allowance for operational profiles. This would allow fuel consumption to be more accurately projected and a larger share of efficiency benefits to accrue to ship owners, thus increasing the return on investment in fuel-saving technologies. This would also require changes to standard charter parties. The credibility of information on new technologies can be improved through intensive collaboration between suppliers of new technologies and shipping companies. In order to overcome risk, government subsidies could provide an incentive. This could have the additional benefit that governments could require publication of results.

  7. Fuel poverty and energy efficiency obligations – A critical assessment of the supplier obligation in the UK

    International Nuclear Information System (INIS)

    Rosenow, Jan; Platt, Reg; Flanagan, Brooke

    2013-01-01

    Energy efficiency obligations (or white certificates) are increasingly used to reduce carbon emissions. While the energy efficiency obligations were originally intended as carbon reduction and not fuel poverty policies, due to recognition of the potential for regressive outcomes they often include provisions for vulnerable and low-income customers. Intuitively, reducing carbon emissions and alleviating fuel poverty seem to be two sides of the same coin. There are, however, considerable tensions between the two when addressed through energy efficiency obligations, particularly arising from the potentially regressive impacts of rising energy prices resulting from such obligations, but also the complexity of targeting fuel poor households and the implications for deliverability. Despite those tensions, the UK government decided to use energy efficiency obligations, the supplier obligation, as the main policy for reducing fuel poverty. In light of the proposals, this paper provides an analysis of the main tensions between carbon reduction and fuel poverty alleviation within energy efficiency obligations, outlines the fuel poverty provisions of the British Supplier Obligation, assesses its rules for identifying the fuel poor, and provides a critical analysis of the planned policy changes. Based on this analysis, alternative approaches to targeting fuel poverty within future supplier obligations are proposed. - Highlights: • First comprehensive analysis of energy savings obligations and fuel poverty. • Systematic comparison of targeting efficiency of fuel poverty programmes. • Critical analysis of fuel poverty provisions in British supplier obligations. • Proposal of a new approach to targeting fuel poverty within energy savings obligations

  8. Molecularly Imprinted Polymer Enables High-Efficiency Recognition and Trapping Lithium Polysulfides for Stable Lithium Sulfur Battery.

    Science.gov (United States)

    Liu, Jie; Qian, Tao; Wang, Mengfan; Liu, Xuejun; Xu, Na; You, Yizhou; Yan, Chenglin

    2017-08-09

    Using molecularly imprinted polymer to recognize various target molecules emerges as a fascinating research field. Herein, we applied this strategy for the first time to efficiently recognize and trap long-chain polysulfides (Li 2 S x , x = 6-8) in lithium sulfur battery to minimize the polysulfide shuttling between anode and cathode, which enables us to achieve remarkable electrochemical performance including a high specific capacity of 1262 mAh g -1 at 0.2 C and superior capacity retention of over 82.5% after 400 cycles at 1 C. The outstanding performance is attributed to the significantly reduced concentration of long-chain polysulfides in electrolyte as evidenced by in situ UV/vis spectroscopy and Li 2 S nucleation tests, which were further confirmed by density functional theory calculations. The molecular imprinting is demonstrated as a promising approach to effectively prevent the free diffusion of long-chain polysulfides, providing a new avenue to efficiently recognize and trap lithium polysulfides for high-performance lithium sulfur battery with greatly suppressed shuttle effect.

  9. Thermodynamic and achievable efficiencies for solar-driven electrochemical reduction of carbon dioxide to transportation fuels

    Science.gov (United States)

    Singh, Meenesh R.; Clark, Ezra L.; Bell, Alexis T.

    2015-11-01

    Thermodynamic, achievable, and realistic efficiency limits of solar-driven electrochemical conversion of water and carbon dioxide to fuels are investigated as functions of light-absorber composition and configuration, and catalyst composition. The maximum thermodynamic efficiency at 1-sun illumination for adiabatic electrochemical synthesis of various solar fuels is in the range of 32-42%. Single-, double-, and triple-junction light absorbers are found to be optimal for electrochemical load ranges of 0-0.9 V, 0.9-1.95 V, and 1.95-3.5 V, respectively. Achievable solar-to-fuel (STF) efficiencies are determined using ideal double- and triple-junction light absorbers and the electrochemical load curves for CO2 reduction on silver and copper cathodes, and water oxidation kinetics over iridium oxide. The maximum achievable STF efficiencies for synthesis gas (H2 and CO) and Hythane (H2 and CH4) are 18.4% and 20.3%, respectively. Whereas the realistic STF efficiency of photoelectrochemical cells (PECs) can be as low as 0.8%, tandem PECs and photovoltaic (PV)-electrolyzers can operate at 7.2% under identical operating conditions. We show that the composition and energy content of solar fuels can also be adjusted by tuning the band-gaps of triple-junction light absorbers and/or the ratio of catalyst-to-PV area, and that the synthesis of liquid products and C2H4 have high profitability indices.

  10. Thermodynamic and achievable efficiencies for solar-driven electrochemical reduction of carbon dioxide to transportation fuels.

    Science.gov (United States)

    Singh, Meenesh R; Clark, Ezra L; Bell, Alexis T

    2015-11-10

    Thermodynamic, achievable, and realistic efficiency limits of solar-driven electrochemical conversion of water and carbon dioxide to fuels are investigated as functions of light-absorber composition and configuration, and catalyst composition. The maximum thermodynamic efficiency at 1-sun illumination for adiabatic electrochemical synthesis of various solar fuels is in the range of 32-42%. Single-, double-, and triple-junction light absorbers are found to be optimal for electrochemical load ranges of 0-0.9 V, 0.9-1.95 V, and 1.95-3.5 V, respectively. Achievable solar-to-fuel (STF) efficiencies are determined using ideal double- and triple-junction light absorbers and the electrochemical load curves for CO2 reduction on silver and copper cathodes, and water oxidation kinetics over iridium oxide. The maximum achievable STF efficiencies for synthesis gas (H2 and CO) and Hythane (H2 and CH4) are 18.4% and 20.3%, respectively. Whereas the realistic STF efficiency of photoelectrochemical cells (PECs) can be as low as 0.8%, tandem PECs and photovoltaic (PV)-electrolyzers can operate at 7.2% under identical operating conditions. We show that the composition and energy content of solar fuels can also be adjusted by tuning the band-gaps of triple-junction light absorbers and/or the ratio of catalyst-to-PV area, and that the synthesis of liquid products and C2H4 have high profitability indices.

  11. Thermodynamic and achievable efficiencies for solar-driven electrochemical reduction of carbon dioxide to transportation fuels

    Science.gov (United States)

    Singh, Meenesh R.; Clark, Ezra L.; Bell, Alexis T.

    2015-01-01

    Thermodynamic, achievable, and realistic efficiency limits of solar-driven electrochemical conversion of water and carbon dioxide to fuels are investigated as functions of light-absorber composition and configuration, and catalyst composition. The maximum thermodynamic efficiency at 1-sun illumination for adiabatic electrochemical synthesis of various solar fuels is in the range of 32–42%. Single-, double-, and triple-junction light absorbers are found to be optimal for electrochemical load ranges of 0–0.9 V, 0.9–1.95 V, and 1.95–3.5 V, respectively. Achievable solar-to-fuel (STF) efficiencies are determined using ideal double- and triple-junction light absorbers and the electrochemical load curves for CO2 reduction on silver and copper cathodes, and water oxidation kinetics over iridium oxide. The maximum achievable STF efficiencies for synthesis gas (H2 and CO) and Hythane (H2 and CH4) are 18.4% and 20.3%, respectively. Whereas the realistic STF efficiency of photoelectrochemical cells (PECs) can be as low as 0.8%, tandem PECs and photovoltaic (PV)-electrolyzers can operate at 7.2% under identical operating conditions. We show that the composition and energy content of solar fuels can also be adjusted by tuning the band-gaps of triple-junction light absorbers and/or the ratio of catalyst-to-PV area, and that the synthesis of liquid products and C2H4 have high profitability indices. PMID:26504215

  12. Effect of operating conditions on energy efficiency for a small passive direct methanol fuel cell

    International Nuclear Information System (INIS)

    Chu Deryn; Jiang Rongzhong

    2006-01-01

    Energy conversion efficiency was studied in a direct methanol fuel cell (DMFC) with an air-breathing cathode using Nafion 117 as electrolyte membrane. The effect of operating conditions, such as methanol concentration, discharge voltage and temperature, on Faradic and energy conversion efficiencies was analyzed under constant voltage discharge with quantitative amount of fuel. Both of Faradic and energy conversion efficiencies decrease significantly with increasing methanol concentration and environmental temperature. The Faradic conversion efficiency can be as high as 94.8%, and the energy conversion efficiency can be as high as 23.9% if the environmental temperature is low enough (10 deg. C) under constant voltage discharge at 0.6 V with 3 M methanol for a DMFC bi-cell. Although higher temperature and higher methanol concentration can achieve higher discharge power, it will result in considerable losses of Faradic and energy conversion efficiencies for using Nafion electrolyte membrane. Development of alternative highly conductive membranes with significantly lower methanol crossover is necessary to avoid loss of Faradic conversion efficiency with temperature and with fuel concentration

  13. Modeling and operation optimization of a proton exchange membrane fuel cell system for maximum efficiency

    International Nuclear Information System (INIS)

    Han, In-Su; Park, Sang-Kyun; Chung, Chang-Bock

    2016-01-01

    Highlights: • A proton exchange membrane fuel cell system is operationally optimized. • A constrained optimization problem is formulated to maximize fuel cell efficiency. • Empirical and semi-empirical models for most system components are developed. • Sensitivity analysis is performed to elucidate the effects of major operating variables. • The optimization results are verified by comparison with actual operation data. - Abstract: This paper presents an operation optimization method and demonstrates its application to a proton exchange membrane fuel cell system. A constrained optimization problem was formulated to maximize the efficiency of a fuel cell system by incorporating practical models derived from actual operations of the system. Empirical and semi-empirical models for most of the system components were developed based on artificial neural networks and semi-empirical equations. Prior to system optimizations, the developed models were validated by comparing simulation results with the measured ones. Moreover, sensitivity analyses were performed to elucidate the effects of major operating variables on the system efficiency under practical operating constraints. Then, the optimal operating conditions were sought at various system power loads. The optimization results revealed that the efficiency gaps between the worst and best operation conditions of the system could reach 1.2–5.5% depending on the power output range. To verify the optimization results, the optimal operating conditions were applied to the fuel cell system, and the measured results were compared with the expected optimal values. The discrepancies between the measured and expected values were found to be trivial, indicating that the proposed operation optimization method was quite successful for a substantial increase in the efficiency of the fuel cell system.

  14. Thermodynamic comparison and efficiency enhancement mechanism of coal to alternative fuel systems

    International Nuclear Information System (INIS)

    Ji, Xiaozhou; Li, Sheng; Gao, Lin; Jin, Hongguang

    2016-01-01

    Highlights: • Energy and exergy analysis are presented to three coal-to-alternative-fuels systems. • Internal reasons for performance differences for different systems are disclosed. • The temperature and heat release of synthesis reactions are key to plant efficiency. • The distillation unit and purge gas recovery are important to efficiency enhancement. - Abstract: Coal to alternative fuels is an important path to enforce energy security and to provide clean energy. In this paper, we use exergy analysis and energy utilization diagram (EUD) methods to disclose the internal reasons for performance differences in typical coal to alternative fuel processes. ASPEN plus software is used to simulate the coal-based energy systems, and the simulation results are verified with engineering data. Results show that coal to substitute natural gas (SNG) process has a higher exergy efficiency of 56.56%, while the exergy efficiency of traditional coal to methanol process is 48.65%. It is indicated that three key factors impact the performance enhancement of coal to alternative fuel process: (1) whether the fuel is distillated, (2) the synthesis temperature and the amount of heat release from reactions, and (3) whether the chemical purge gases from synthesis and distillation units are recovered. Distillation unit is not recommended and synthesis at high temperature and with large heat release is preferable for coal to alternative fuel systems. Gasification is identified as the main source of exergy destruction, and thereby how to decrease its destruction is the key direction of plant efficiency improvement in the future. Also, decreasing the power consumption in air separation unit by seeking for advanced technologies, i.e. membrane, or using another kind of oxidant is another direction to improve plant performance.

  15. Ethanol-fueled low temperature combustion: A pathway to clean and efficient diesel engine cycles

    International Nuclear Information System (INIS)

    Asad, Usman; Kumar, Raj; Zheng, Ming; Tjong, Jimi

    2015-01-01

    Highlights: • Concept of ethanol–diesel fueled Premixed Pilot Assisted Combustion (PPAC). • Ultra-low NOx and soot with diesel-like thermal efficiency across the load range. • Close to TDC pilot injection timing for direct combustion phasing control. • Minimum pilot quantity (15% of total energy input) for clean, stable operation. • Defined heat release profile distribution (HRPD) to optimize pilot-ethanol ratio. - Abstract: Low temperature combustion (LTC) in diesel engines offers the benefits of ultra-low NOx and smoke emissions but suffers from lowered energy efficiency due to the high reactivity and low volatility of diesel fuel. Ethanol from renewable biomass provides a viable alternate to the petroleum based transportation fuels. The high resistance to auto-ignition (low reactivity) and its high volatility make ethanol a suitable fuel for low temperature combustion (LTC) in compression-ignition engines. In this work, a Premixed Pilot Assisted Combustion (PPAC) strategy comprising of the port fuel injection of ethanol, ignited with a single diesel pilot injection near the top dead centre has been investigated on a single-cylinder high compression ratio diesel engine. The impact of the diesel pilot injection timing, ethanol to diesel quantity ratio and exhaust gas recirculation on the emissions and efficiency are studied at 10 bar IMEP. With the lessons learnt, successful ethanol–diesel PPAC has been demonstrated up to a load of 18 bar IMEP with ultra-low NOx and soot emissions across the full load range. The main challenge of PPAC is the reduced combustion efficiency especially at low loads; therefore, the authors have presented a combustion control strategy to allow high efficiency, clean combustion across the load range. This work entails to provide a detailed framework for the ethanol-fueled PPAC to be successfully implemented.

  16. Screening of tank-to-wheel efficiencies for CNG, DME and methanol-ethanol fuel blends in road transport

    Energy Technology Data Exchange (ETDEWEB)

    Kappel, J.; Vad Mathiesen, B.

    2013-04-15

    The purpose of this report is to evaluate the fuel efficiency of selected alternative fuels based on vehicle performance in a standardised drive cycle test. All studies reviewed are either based on computer modelling of current or future vehicles or tests of just one alternative fuel, under different conditions and concentrations against either petrol or diesel. No studies were found testing more than one type of alternative fuel in the same setup. Due to this one should be careful when comparing results on several alternative fuels. Only few studies have been focused on vehicle energy efficiency. This screening indicates methanol, methanol-ethanol blends and CNG to be readily availability, economic feasible and with the introduction of the DISI engine not technologically challenging compared to traditional fuels. Studies across fuel types indicate a marginally better fuel utilization for methanol-ethanol fuel mixes. (Author)

  17. Efficiency versus cost of alternative fuels from renewable resources: outlining decision parameters

    International Nuclear Information System (INIS)

    Kaul, Sanjay; Edinger, Raphael

    2004-01-01

    In the discussion of traditional versus renewable energies and alternatives to conventional crude oil-based fuels in the transportation sector, efficiency calculations are but one decision making parameter. Comparing the assets and liabilities of fossil-based and renewable fuels in the transportation sector, further aspects such as centralized versus decentralized technologies, cost evaluations, taxation, and ecological/social benefits have to be taken into account. This paper outlines the driving parameters for shifting toward alternative fuels based on fossil or renewable resources and their use in innovative vehicle technologies such as advanced internal combustion and fuel cell electric drive systems. For the decision in favor or against an alternative fuel to be introduced to the mass market, automotive technologies and the energy supply system have to be examined in an integrated way. From an economic and technological perspective, some fuels may be even incompatible with the trend toward using renewable resources that have advantages in decentralized systems. Beyond efficiency calculations, political and industrial interests arise and may be influential to reshaping our currently crude oil-based mobility sector

  18. Development of an Optimal Controller and Validation Test Stand for Fuel Efficient Engine Operation

    Science.gov (United States)

    Rehn, Jack G., III

    There are numerous motivations for improvements in automotive fuel efficiency. As concerns over the environment grow at a rate unmatched by hybrid and electric automotive technologies, the need for reductions in fuel consumed by current road vehicles has never been more present. Studies have shown that a major cause of poor fuel consumption in automobiles is improper driving behavior, which cannot be mitigated by purely technological means. The emergence of autonomous driving technologies has provided an opportunity to alleviate this inefficiency by removing the necessity of a driver. Before autonomous technology can be relied upon to reduce gasoline consumption on a large scale, robust programming strategies must be designed and tested. The goal of this thesis work was to design and deploy an autonomous control algorithm to navigate a four cylinder, gasoline combustion engine through a series of changing load profiles in a manner that prioritizes fuel efficiency. The experimental setup is analogous to a passenger vehicle driving over hilly terrain at highway speeds. The proposed approach accomplishes this using a model-predictive, real-time optimization algorithm that was calibrated to the engine. Performance of the optimal control algorithm was tested on the engine against contemporary cruise control. Results indicate that the "efficient'' strategy achieved one to two percent reductions in total fuel consumed for all load profiles tested. The consumption data gathered also suggests that further improvements could be realized on a different subject engine and using extended models and a slightly modified optimal control approach.

  19. The role of nuclear energy in the more efficient exploitation of fossil fuel resources

    International Nuclear Information System (INIS)

    Seifritz, W.

    1978-01-01

    The energy theory of value, being a valuable addition to the debate on the rational exploitation of man's energy reserves, is applied in order to clarify the presently confused energy input/output relations for nuclear and solar systems as they interact with fossil fuel. It is shown on the basis of purely energetics considerations that the nuclear route - at present and in future - is a very efficient way to stretch out and finally to substitute for the limited fossil fuel resources. This is particularly true if one considers the transitory phase where the substituting process has to exhibit a rapid exponential growth rate. The energetical effectiveness of the production of a synthetic fuel, as for example hydrogen by water splitting processes, is addressed at the end and serves to give an idea how effectively the energy available in fossil fuels can be amplified by virtue of the coupling of nuclear energy into the process. (author)

  20. Effects of miles per gallon feedback on fuel efficiency in gas-powered cars.

    Science.gov (United States)

    2009-10-01

    This study tested the impact of continuous miles per gallon (MPG) feedback on driving : behavior and fuel efficiency in gas-powered cars. We compared an experimental condition, : where drivers received real-time MPG feedback and a tip sheet, to a con...

  1. 49 CFR 575.106 - Tire fuel efficiency consumer information program.

    Science.gov (United States)

    2010-10-01

    ... to provide information indicating the relative performance of replacement passenger car tires in the... achieve the level of performance represented by each rating. (A) Ratings. Each tire shall be rated with... 49 Transportation 7 2010-10-01 2010-10-01 false Tire fuel efficiency consumer information program...

  2. Disturbance rejection in diesel engines for low emissions and high fuel efficiency

    NARCIS (Netherlands)

    Criens, C. H. A.; Willems, F. P. T.; Van Keulen, T. A. C.; Steinbuch, M.

    2015-01-01

    This brief presents a novel and time-efficient control design for modern heavy-duty diesel engines using a variable geometry turbine and an exhaust gas recirculation valve. The goal is to simultaneously and robustly achieve low fuel consumption and low emissions of nitrogen oxides (NOx) and

  3. Fuel Application Efficiency in Ideal Cycle of Gas Turbine Plant with Isobaric Heat Supply

    Directory of Open Access Journals (Sweden)

    A. P. Nesenchuk

    2013-01-01

    Full Text Available The paper reveals expediency to use in prospect fuels with maximum value  Qнр∑Vi and minimum theoretical burning temperature in order to obtain maximum efficiency of the ideal cycle in GTP with isobaric heat supply.

  4. Sustainable Transportation: Accelerating Widespread Adoption of Energy Efficient Vehicles & Fuels (Brochure)

    Energy Technology Data Exchange (ETDEWEB)

    2014-12-01

    While energy efficient transportation strategies have the potential to simultaneously slash oil consumption and reduce greenhouse gas (GHG) emissions, a truly sustainable solution will require more than just putting drivers behind the wheels of new fuel-efficient cars. As the only national laboratory dedicated 100% to renewable energy and energy efficiency, the National Renewable Energy Laboratory (NREL) accelerates widespread adoption of high-performance, low-emission, energy-efficient passenger and freight vehicles, as well as alternative fuels and related infrastructure. Researchers collaborate closely with industry, government, and research partners, using a whole-systems approach to design better batteries, drivetrains, and engines, as well as thermal management, energy storage, power electronic, climate control, alternative fuel, combustion, and emission systems. NREL's sustainable transportation research, development, and deployment (RD&D) efforts are not limited to vehicles, roads, and fueling stations. The lab also explores ways to save energy and reduce GHGs by integrating transportation technology advancements with renewable energy generation, power grids and building systems, urban planning and policy, and fleet operations.

  5. Why aircraft will fly more fuel-efficiently on FRIDAY : The FRIDAY route charges method

    NARCIS (Netherlands)

    Verbeek, R.J.D.; Visser, H.G.; Lovell, D.; Fricke, H.

    2016-01-01

    The Single European Sky is being introduced to improve the efficiency of flight and traffic operations by reforming the air traffic management system. Despite all of these technical advances, airlines choose detours to avoid high route charges. This mechanism is intensified when fuel prices are low.

  6. Screening of tank-to-wheel efficiencies for CNG, DME and methanol-ethanol fuel blends in road transport

    DEFF Research Database (Denmark)

    Kappel, Jannik; Mathiesen, Brian Vad

    efficiency. This screening indicates methanol, methanol-ethanol blends and CNG to be readily availability, economic feasible and with the introduction of the DISI engine not technologically challenging compared to traditional fuels. Studies across fuel types indicate a marginally better fuel utilization...

  7. Rational engineering of p-hydroxybenzoate hydroxylase to enable efficient gallic acid synthesis via a novel artificial biosynthetic pathway.

    Science.gov (United States)

    Chen, Zhenya; Shen, Xiaolin; Wang, Jian; Wang, Jia; Yuan, Qipeng; Yan, Yajun

    2017-11-01

    Gallic acid (GA) is a naturally occurring phytochemical that has strong antioxidant and antibacterial activities. It is also used as a potential platform chemical for the synthesis of diverse high-value compounds. Hydrolytic degradation of tannins by acids, bases or microorganisms serves as a major way for GA production, which however, might cause environmental pollution and low yield and efficiency. Here, we report a novel approach for efficient microbial production of GA. First, structure-based rational engineering of PobA, a p-hydroxybenzoate hydroxylase from Pseudomonas aeruginosa, generated a new mutant, Y385F/T294A PobA, which displayed much higher activity toward 3,4-dihydroxybenzoic acid (3,4-DHBA) than the wild-type and any other reported mutants. Remarkably, expression of this mutant in Escherichia coli enabled generation of 1149.59 mg/L GA from 1000 mg/L 4-hydroxybenzoic acid (4-HBA), representing a 93% molar conversion ratio. Based on that, we designed and reconstituted a novel artificial biosynthetic pathway of GA and achieved 440.53 mg/L GA production from simple carbon sources in E. coli. Further enhancement of precursor supply through reinforcing shikimate pathway was able to improve GA de novo production to 1266.39 mg/L in shake flasks. Overall, this study not only led to the development of a highly active PobA variant for hydroxylating 3,4-DHBA into GA via structure-based protein engineering approach, but also demonstrated a promising pathway for bio-based manufacturing of GA and its derived compounds. Biotechnol. Bioeng. 2017;114: 2571-2580. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  8. Alternative Concept to Enhance the Disposal Efficiency for CANDU Spent Fuel Disposal System

    International Nuclear Information System (INIS)

    Lee, Jong Youl; Cho, Dong Geun; Kook, Dong Hak; Lee, Min Soo; Choi, Heui Joo

    2011-01-01

    There are two types of nuclear reactors in Korea and they are PWR type and CANDU type. The safe management of the spent fuels from these reactors is very important factor to maintain the sustainable energy supply with nuclear power plant. In Korea, a reference disposal system for the spent fuels has been developed through a study on the direct disposal of the PWR and CANDU spent fuel. Recently, the research on the demonstration and the efficiency analyses of the disposal system has been performed to make the disposal system safer and more economic. PWR spent fuels which include a lot of reusable material can be considered being recycled and a study on the disposal of HLW from this recycling process is being performed. CANDU spent fuels are considered being disposed of directly in deep geological formation, since they have little reusable material. In this study, based on the Korean Reference spent fuel disposal System (KRS) which was to dispose of both PWR type and CANDU type, the more effective CANDU spent fuel disposal systems were developed. To do this, the disposal canister for CANDU spent fuels was modified to hold the storage basket for 60 bundles which is used in nuclear power plant. With these modified disposal canister concepts, the disposal concepts to meet the thermal requirement that the temperature of the buffer materials should not be over 100 .deg. C were developed. These disposal concepts were reviewed and analyzed in terms of disposal effective factors which were thermal effectiveness, U-density, disposal area, excavation volume, material volume etc. and the most effective concept was proposed. The results of this study will be used in the development of various wastes disposal system together with the HLW wastes from the PWR spent fuel recycling process.

  9. Developing an energy efficient steam reforming process to produce hydrogen from sulfur-containing fuels

    Science.gov (United States)

    Simson, Amanda

    Hydrogen powered fuel cells have the potential to produce electricity with higher efficiency and lower emissions than conventional combustion technology. In order to realize the benefits of a hydrogen fuel cell an efficient method to produce hydrogen is needed. Currently, over 90% of hydrogen is produced from the steam reforming of natural gas. However, for many applications including fuel cell vehicles, the use of a liquid fuel rather than natural gas is desirable. This work investigates the feasibility of producing hydrogen efficiently by steam reforming E85 (85% ethanol/15% gasoline), a commercially available sulfur-containing transportation fuel. A Rh-Pt/SiO2-ZrO2 catalyst has demonstrated good activity for the E85 steam reforming reaction. An industrial steam reforming process is often run less efficiently, with more water and at higher temperatures, in order to prevent catalyst deactivation. Therefore, it is desirable to develop a process that can operate without catalyst deactivation at more energy efficient conditions. In this study, the steam reforming of a sulfur-containing fuel (E85) was studied at near stoichiometric steam/carbon ratios and at 650C, conditions at which catalyst deactivation is normally measured. At these conditions the catalyst was found to be stable steam reforming a sulfur-free E85. However, the addition of low concentrations of sulfur significantly deactivated the catalyst. The presence of sulfur in the fuel caused catalyst deactivation by promoting ethylene which generates surface carbon species (coke) that mask catalytic sites. The amount of coke increased during time on stream and became increasingly graphitic. However, the deactivation due to both sulfur adsorption and coke formation was reversible with air treatment at 650°C. However, regenerations were found to reduce the catalyst life. Air regenerations produce exotherms on the catalyst surface that cause structural changes to the catalyst. During regenerations the

  10. Investigations on burning efficiency and exhaust emission of in-line type emulsified fuel system

    Energy Technology Data Exchange (ETDEWEB)

    Tseng, Y.K. [National Chinyi University of Technology (Taiwan). Dept. of Mechanical Engineering; Cheng, H.C. [Point Environmental Protection Technology Company Limited (Taiwan)

    2011-07-28

    In this research, the burning efficiency as well as exhaust emission of a new water-in-oil emulsified fuel system was studied. This emulsified system contains two core processes, the first one is to mix 97% water with 3% emulsifier by volume, and get the milk-like emulsified liquid, while the second one is to compound the milk-like emulsified liquid with heavy oil then obtain the emulsified fuel. In order to overcome the used demulsification problem during in reserve or in transport, this system was designed as a made and use in-line type. From the results of a series of burning tests, the fuel saving can be 8--15%. Also, from the comparison of decline for the heat value and total energy output of emulsified fuel, one can find that the water as the dispersed phase in the combustion process will lead to a micro-explosion as well as the water gas effect, both can raise the combustion temperature and burning efficiency. By comparing the waste gas emission of different types of emulsified fuel, one can know that, the CO2 emission reduces approximately 14%, and NOx emission reduces above 46%, meaning the reduction of the exhaust gas is truly effective. From the exhaust temperature of tail pipe, the waste heat discharge also may reduce 27%, it is quite advantageous to the global warming as well as earth environmental protection.

  11. 75 FR 81952 - Greenhouse Gas Emissions Standards and Fuel Efficiency Standards for Medium- and Heavy-Duty...

    Science.gov (United States)

    2010-12-29

    ...-HQ-OAR-2010-0162; FRL-9219-4; NHTSA 2010-0079] RIN 2060-AP61; RIN 2127-AK74 Greenhouse Gas Emissions... will increase fuel efficiency and reduce greenhouse gas emissions for on-road heavy-duty vehicles...-Duty National Program that will increase fuel efficiency and reduce greenhouse gas emissions for on...

  12. Energy Management Strategies based on efficiency map for Fuel Cell Hybrid Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Feroldi, Diego; Serra, Maria; Riera, Jordi [Institut de Robotica i Informatica Industrial (CSIC-UPC), C. Llorens i Artigas 4, 08028 Barcelona (Spain)

    2009-05-15

    The addition of a fast auxiliary power source like a supercapacitor bank in fuel cell-based vehicles has a great potential because permits a significant reduction of the hydrogen consumption and an improvement of the vehicle efficiency. The Energy Management Strategies, commanding the power split between the power sources in the hybrid arrangement to fulfil the power requirement, perform a fundamental role to achieve this objective. In this work, three strategies based on the knowledge of the fuel cell efficiency map are proposed. These strategies are attractive due to the relative simplicity of the real time implementation and the good performance. The strategies are tested both in a simulation environment and in an experimental setup using a 1.2-kW PEM fuel cell. The results, in terms of hydrogen consumption, are compared with an optimal case, which is assessed trough an advantageous technique also introduced in this work and with a pure fuel cell vehicle as well. This comparative reveals high efficiency and good performance, allowing to save up to 26% of hydrogen in urban scenarios. (author)

  13. Final Report: Utilizing Alternative Fuel Ignition Properties to Improve SI and CI Engine Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Wooldridge, Margaret; Boehman, Andre; Lavoie, George; Fatouraie, Mohammad

    2017-11-30

    Experimental and modeling studies were completed to explore leveraging physical and chemical fuel properties for improved thermal efficiency of internal combustion engines. Fundamental studies of the ignition chemistry of ethanol and iso-octane blends and constant volume spray chamber studies of gasoline and diesel sprays supported the core research effort which used several reciprocating engine platforms. Single cylinder spark ignition (SI) engine studies were carried out to characterize the impact of ethanol/gasoline, syngas (H2 and CO)/gasoline and other oxygenate/gasoline blends on engine performance. The results of the single-cylinder engine experiments and other data from the literature were used to train a GT Power model and to develop a knock criteria based on reaction chemistry. The models were used to interpret the experimental results and project future performance. Studies were also carried out using a state of the art, direct injection (DI) turbocharged multi- cylinder engine with piezo-actuated fuel injectors to demonstrate the promising spray and spark timing strategies from single-cylinder engine studies on the multi-cylinder engine. Key outcomes and conclusions of the studies were: 1. Efficiency benefits of ethanol and gasoline fuel blends were consistent and substantial (e.g. 5-8% absolute improvement in gross indicated thermal efficiency (GITE)). 2. The best ethanol/gasoline blend (based on maximum thermal efficiency) was determined by the engine hardware and limits based on component protection (e.g. peak in-cylinder pressure or maximum turbocharger inlet temperature) – and not by knock limits. Blends with <50% ethanol delivered significant thermal efficiency gains with conventional SI hardware while maintain good safety integrity to the engine hardware. 3. Other compositions of fuel blends including syngas (H2 and CO) and other dilution strategies provided significant efficiency gains as well (e.g. 5% absolute improvement in ITE). 4. When the

  14. Combustion studies of coal derived solid fuels by thermogravimetric analysis. III. Correlation between burnout temperature and carbon combustion efficiency

    Science.gov (United States)

    Rostam-Abadi, M.; DeBarr, J.A.; Chen, W.T.

    1990-01-01

    Burning profiles of 35-53 ??m size fractions of an Illinois coal and three partially devolatilized coals prepared from the original coal were obtained using a thermogravimetric analyzer. The burning profile burnout temperatures were higher for lower volatile fuels and correlated well with carbon combustion efficiencies of the fuels when burned in a laboratory-scale laminar flow reactor. Fuels with higher burnout temperatures had lower carbon combustion efficiencies under various time-temperature conditions in the laboratory-scale reactor. ?? 1990.

  15. Improving Catalyst Efficiency in Bio-Based Hydrocarbon Fuels; NREL (National Renewable Energy Laboratory)

    Energy Technology Data Exchange (ETDEWEB)

    None

    2015-06-01

    This article investigates upgrading biomass pyrolysis vapors to form hydrocarbon fuels and chemicals using catalysts with different concentrations of acid sites. It shows that greater separation of acid sites makes catalysts more efficient at producing hydrocarbon fuels and chemicals. The conversion of biomass into liquid transportation fuels has attracted significant attention because of depleting fossil fuel reserves and environmental concerns resulting from the use of fossil fuels. Biomass is a renewable resource, which is abundant worldwide and can potentially be exploited to produce transportation fuels that are less damaging to the environment. This renewable resource consists of cellulose (40–50%), hemicellulose (25–35%), and lignin (16–33%) biopolymers in addition to smaller quantities of inorganic materials such as silica and alkali and alkaline earth metals (calcium and potassium). Fast pyrolysis is an attractive thermochemical technology for converting biomass into precursors for hydrocarbon fuels because it produces up to 75 wt% bio-oil,1 which can be upgraded to feedstocks and/or blendstocks for further refining to finished fuels. Bio-oil that has not been upgraded has limited applications because of the presence of oxygen-containing functional groups, derived from cellulose, hemicellulose and lignin, which gives rise to high acidity, high viscosity, low heating value, immiscibility with hydrocarbons and aging during storage. Ex situ catalytic vapor phase upgrading is a promising approach for improving the properties of bio-oil. The goal of this process is to reject oxygen and produce a bio-oil with improved properties for subsequent downstream conversion to hydrocarbons.

  16. Peak oil demand: the role of fuel efficiency and alternative fuels in a global oil production decline.

    Science.gov (United States)

    Brandt, Adam R; Millard-Ball, Adam; Ganser, Matthew; Gorelick, Steven M

    2013-07-16

    Some argue that peak conventional oil production is imminent due to physical resource scarcity. We examine the alternative possibility of reduced oil use due to improved efficiency and oil substitution. Our model uses historical relationships to project future demand for (a) transport services, (b) all liquid fuels, and (c) substitution with alternative energy carriers, including electricity. Results show great increases in passenger and freight transport activity, but less reliance on oil. Demand for liquids inputs to refineries declines significantly after 2070. By 2100 transport energy demand rises >1000% in Asia, while flattening in North America (+23%) and Europe (-20%). Conventional oil demand declines after 2035, and cumulative oil production is 1900 Gbbl from 2010 to 2100 (close to the U.S. Geological Survey median estimate of remaining oil, which only includes projected discoveries through 2025). These results suggest that effort is better spent to determine and influence the trajectory of oil substitution and efficiency improvement rather than to focus on oil resource scarcity. The results also imply that policy makers should not rely on liquid fossil fuel scarcity to constrain damage from climate change. However, there is an unpredictable range of emissions impacts depending on which mix of substitutes for conventional oil gains dominance-oil sands, electricity, coal-to-liquids, or others.

  17. Thermodynamic and achievable efficiencies for solar-driven electrochemical reduction of carbon dioxide to transportation fuels

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Meenesh R. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Joint Center for Artificial Photosynthesis, Material Science Division; Clark, Ezra L. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Joint Center for Artificial Photosynthesis, Material Science Division; Univ. of California, Berkeley, CA (United States). Dept. of Chemical & Biomolecular Engineering; Bell, Alexis T. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Joint Center for Artificial Photosynthesis, Material Science Division; Univ. of California, Berkeley, CA (United States). Dept. of Chemical & Biomolecular Engineering

    2015-10-26

    Thermodynamic, achievable, and realistic efficiency limits of solar-driven electrochemical conversion of water and carbon dioxide to fuels are investigated as functions of light-absorber composition and configuration, and catalyst composition. The maximum thermodynamic efficiency at 1-sun illumination for adiabatic electrochemical synthesis of various solar fuels is in the range of 32–42%. Single-, double-, and triple-junction light absorbers are found to be optimal for electrochemical load ranges of 0–0.9 V, 0.9–1.95 V, and 1.95–3.5 V, respectively. Achievable solar-to-fuel (STF) efficiencies are determined using ideal double- and triple-junction light absorbers and the electrochemical load curves for CO2 reduction on silver and copper cathodes, and water oxidation kinetics over iridium oxide. The maximum achievable STF efficiencies for synthesis gas (H2 and CO) and Hythane (H2 and CH4) are 18.4% and 20.3%, respectively. Whereas the realistic STF efficiency of photoelectrochemical cells (PECs) can be as low as 0.8%, tandem PECs and photovoltaic (PV)-electrolyzers can operate at 7.2% under identical operating conditions. Finally, we show that the composition and energy content of solar fuels can also be adjusted by tuning the band-gaps of triple-junction light absorbers and/or the ratio of catalyst-to-PV area, and that the synthesis of liquid products and C2H4 have high profitability indices.

  18. Direct synthesis of Pt-free catalyst on gas diffusion layer of fuel cell and usage of high boiling point fuels for efficient utilization of waste heat

    International Nuclear Information System (INIS)

    Nandan, Ravi; Goswami, Gopal Krishna; Nanda, Karuna Kar

    2017-01-01

    Graphical abstract: Direct-grown boron-doped carbon nanotubes on gas-diffusion layer as efficient Pt-free cathode catalyst for alcohol fuel cells, high boiling point fuels used to obtain hot fuels for the enhancement of cell performance that paves the way for the utilization of waste heat. Display Omitted -- Highlights: •One-step direct synthesis of boron-doped carbon nanotubes (BCNTs) on gas diffusion layer (GDL). •Home built fuel-cell testing using BCNTs on GDL as Pt-free cathode catalyst. •BCNTs exhibit concentration dependent oxygen reduction reaction and the cell performance. •Effective utilization of waste heat to raise the fuel temperature. •Fuel selectivity to raise the fuel temperature and the overall performance of the fuel cells. -- Abstract: Gas diffusion layers (GDL) and electrocatalysts are integral parts of fuel cells. It is, however, a challenging task to grow Pt-free robust electrocatalyst directly on GDL for oxygen reduction reaction (ORR) – a key reaction in fuel cells. Here, we demonstrate that boron-doped carbon nanotubes (BCNTs) grown directly on gas-diffusion layer (which avoid the need of ionomer solution used for catalyst loading) can be used as efficient Pt-free catalyst in alcohol fuel cells. Increase in boron concentration improves the electrochemical ORR activity in terms of onset and ORR peak positions, half-wave potentials and diffusion-limited current density that ensure the optimization of the device performance. The preferential 4e − pathway, excellent cell performance, superior tolerance to fuel crossover and long-term stability makes directly grown BCNTs as an efficient Pt-free cathode catalyst for cost-effective fuel cells. The maximum power density of the fuel cell is found to increase monotonically with boron concentration. In addition to the application of BCNTs in fuel cell, we have introduced the concept of hot fuels so that waste heat can effectively be used and external power sources can be avoided. The fuel

  19. Review and analysis of potential safety impacts of and regulatory barriers to fuel efficiency technologies and alternative fuels in medium- and heavy-duty vehicles

    Science.gov (United States)

    2015-06-01

    This report summarizes a safety analysis of medium- and heavy-duty vehicles (MD/HDVs) equipped with fuel efficiency (FE) technologies and/or using alternative fuels (natural gas-CNG and LNG, propane, biodiesel and power train electrification). The st...

  20. Fuel taxes, motor vehicle emission standards and patents related to the fuel-efficiency and emissions of motor vehicles. Joint Meetings of Tax and Environment Experts

    International Nuclear Information System (INIS)

    Vollebergh, H.

    2010-01-01

    Contribution to the project on Taxation, Innovation and the Environment of OECD's Joint Meetings of Tax and Environment Experts. It studies the impacts of motor vehicle fuel taxes and mandatory fuel efficiency standards on relevant car-related innovation activity in selected car-producing countries.

  1. Efficiency and exhaust gas analysis of variable compression ratio spark ignition engine fuelled with alternative fuels

    Energy Technology Data Exchange (ETDEWEB)

    Seshaiah, N. [Mechanical Engineering Department, M.I.T.S, Madanapalle, Angallu-517325, A.P. (India)

    2010-07-01

    Considering energy crises and pollution problems today, investigations have been concentrated on decreasing fuel consumption by using alternative fuels and on lowering the concentration of toxic components in combustion products. In the present work, the variable compression ratio spark ignition engine designed to run on gasoline has been tested with pure gasoline, LPG (Isobutene), and gasoline blended with ethanol 10%, 15%, 25% and 35% by volume. Also, the gasoline mixed with kerosene at 15%, 25% and 35% by volume without any engine modifications has been tested and presented the result. Brake thermal and volumetric efficiency variation with brake load is compared and presented. CO and CO2 emissions have been also compared for all tested fuels.

  2. Fuel efficiency of conventional design tractors diesel engines in relation to new design

    Directory of Open Access Journals (Sweden)

    Jevtić Jeremija

    2006-01-01

    Full Text Available Total consumption of all types of energies is rather high nowadays with constant tendency of increasing. Transport section is one of the highest consumers of energy obtained from fossil fuels. It is absolutely clear that the reduction of energy consumption and the protection of environment - exhaust emission reduction, i. e. cleaner air, will be one of the main tasks of automotive industry in the first decades of the 21st century. In spite of its superiority over the petrol engine in respect of the fuel consumption, a diesel engine "suffers" from the increased exhaust emission, particles and NOx first of all and also from the noise and vibrations. The paper gives a review of fuel efficiency of conventional design tractors diesel engines in relation to new design. .

  3. Emission performance and combustion efficiency of a conical fluidized-bed combustor firing various biomass fuels

    International Nuclear Information System (INIS)

    Permchart, W.; Kouprianov, V.I.

    2004-01-01

    This paper summarizes the results of an experimental study on combustion of three distinct biomass fuels (sawdust, rice husk and pre-dried sugar cane bagasse) in a single fluidized-bed combustor (FBC) with a conical bed using silica sand as the inert bed material. Temperature, CO, NO and O 2 concentrations along the combustor height as well as in flue (stack) gas were measured in the experimental tests. The effects of fuel properties and operating conditions (load and excess air) on these variables were investigated. Both CO and NO axial profiles were found to have a maximum whose location divides conventionally the combustor volume into formation (lower) and reduction (upper) regions for these pollutants. Based on CO emission and unburned carbon content in fly ash, the combustion efficiency of the conical FBC was quantified for the selected biomass fuels fired under different operating conditions. (Author)

  4. A New Hybrid Proton-Exchange-Membrane Fuel Cells-Battery Power System with Efficiencies Considered

    Science.gov (United States)

    Chao, Chung-Hsing; Shieh, Jenn-Jong

    Hybrid systems, based on lead-acid or lithium-ion batteries and proton-exchange-membrane fuel cells (PEMFCs), give the possibility of combining the benefit of both technologies. The merits of high energy density and power density for different applications are discussed in this paper in recognition of the practical realization of such hybrid power systems. Furthermore, experimental data for such a hybrid system is described and the results are shown and discussed. The results show that the combination of lead-acid batteries or lithium-ion batteries and PEMFCs shows advantages in cases of applications with high peak power requirements, such as electric scooters and applications where the fuel cell (FC) is used as an auxiliary power-supply to recharge the battery. The high efficiency of FCs operating with a partial load results in a good fuel economy for the purpose of recharging batteries within a FC system.

  5. Improvement of operation efficiency for WWER-440 and WWER-1000 for TRIGON fuel assembly design features

    Energy Technology Data Exchange (ETDEWEB)

    Silberstein, A [European WWER Fuels GmbH, Lyon (France)

    1994-12-31

    TRIGON 440 and TRIGON 1000 fuel assemblies and their assembly matching counterparts are described. Their role in increasing the efficiency of WWER reactors is stressed. Special attention is paid to their design features as well as calibrated means of predicting behaviour under irradiation from light water reactor core operation. They reduce the fuel cycle cost as a result of the reduced need for natural uranium which have to be enriched and of the smaller number of fuel assemblies which have to be fabricated, stored or reprocessed. The improved control assemblies bring comfort to the plant operator due to intrinsic progress in safety with respect to accidental situation, trouble-free behaviour and long time utilization in the reactor. 14 figs.

  6. FY2015 ceramic fuels development annual highlights

    Energy Technology Data Exchange (ETDEWEB)

    Mcclellan, Kenneth James [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)

    2015-09-22

    Key challenges for the Advanced Fuels Campaign are the development of fuel technologies to enable major increases in fuel performance (safety, reliability, power and burnup) beyond current technologies, and development of characterization methods and predictive fuel performance models to enable more efficient development and licensing of advanced fuels. Ceramic fuel development activities for fiscal year 2015 fell within the areas of 1) National and International Technical Integration, 2) Advanced Accident Tolerant Ceramic Fuel Development, 3) Advanced Techniques and Reference Materials Development, and 4) Fabrication of Enriched Ceramic Fuels. High uranium density fuels were the focus of the ceramic fuels efforts. Accomplishments for FY15 primarily reflect the prioritization of identification and assessment of new ceramic fuels for light water reactors which have enhanced accident tolerance while also maintaining or improving normal operation performance, and exploration of advanced post irradiation examination techniques which will support more efficient testing and qualification of new fuel systems.

  7. FY2016 Ceramic Fuels Development Annual Highlights

    Energy Technology Data Exchange (ETDEWEB)

    Mcclellan, Kenneth James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-01-24

    Key challenges for the Advanced Fuels Campaign are the development of fuel technologies to enable major increases in fuel performance (safety, reliability, power and burnup) beyond current technologies, and development of characterization methods and predictive fuel performance models to enable more efficient development and licensing of advanced fuels. Ceramic fuel development activities for fiscal year 2016 fell within the areas of 1) National and International Technical Integration, 2) Advanced Accident Tolerant Ceramic Fuel Development, 3) Advanced Techniques and Reference Materials Development, and 4) Fabrication of Enriched Ceramic Fuels. High uranium density fuels were the focus of the ceramic fuels efforts. Accomplishments for FY16 primarily reflect the prioritization of identification and assessment of new ceramic fuels for light water reactors which have enhanced accident tolerance while also maintaining or improving normal operation performance, and exploration of advanced post irradiation examination techniques which will support more efficient testing and qualification of new fuel systems.

  8. Engine-integrated solid oxide fuel cells for efficient electrical power generation on aircraft

    Science.gov (United States)

    Waters, Daniel F.; Cadou, Christopher P.

    2015-06-01

    This work investigates the use of engine-integrated catalytic partial oxidation (CPOx) reactors and solid oxide fuel cells (SOFCs) to reduce fuel burn in vehicles with large electrical loads like sensor-laden unmanned air vehicles. Thermodynamic models of SOFCs, CPOx reactors, and three gas turbine (GT) engine types (turbojet, combined exhaust turbofan, separate exhaust turbofan) are developed and checked against relevant data and source material. Fuel efficiency is increased by 4% and 8% in the 50 kW and 90 kW separate exhaust turbofan systems respectively at only modest cost in specific power (8% and 13% reductions respectively). Similar results are achieved in other engine types. An additional benefit of hybridization is the ability to provide more electric power (factors of 3 or more in some cases) than generator-based systems before encountering turbine inlet temperature limits. A sensitivity analysis shows that the most important parameters affecting the system's performance are operating voltage, percent fuel oxidation, and SOFC assembly air flows. Taken together, this study shows that it is possible to create a GT-SOFC hybrid where the GT mitigates balance of plant losses and the SOFC raises overall system efficiency. The result is a synergistic system with better overall performance than stand-alone components.

  9. Dual-Fuel Combustion for Future Clean and Efficient Compression Ignition Engines

    Directory of Open Access Journals (Sweden)

    Jesús Benajes

    2016-12-01

    Full Text Available Stringent emissions limits introduced for internal combustion engines impose a major challenge for the research community. The technological solution adopted by the manufactures of diesel engines to meet the NOx and particle matter values imposed in the EURO VI regulation relies on using selective catalytic reduction and particulate filter systems, which increases the complexity and cost of the engine. Alternatively, several new combustion modes aimed at avoiding the formation of these two pollutants by promoting low temperature combustion reactions, are the focus of study nowadays. Among these new concepts, the dual-fuel combustion mode known as reactivity controlled compression ignition (RCCI seems more promising because it allows better control of the combustion process by means of modulating the fuel reactivity depending on the engine operating conditions. The present experimental work explores the potential of different strategies for reducing the energy losses with RCCI in a single-cylinder research engine, with the final goal of providing the guidelines to define an efficient dual-fuel combustion system. The results demonstrate that the engine settings combination, piston geometry modification, and fuel properties variation are good methods to increase the RCCI efficiency while maintaining ultra-low NOx and soot emissions for a wide range of operating conditions.

  10. Efficient Biomass Fuel Cell Powered by Sugar with Photo- and Thermal-Catalysis by Solar Irradiation.

    Science.gov (United States)

    Liu, Wei; Gong, Yutao; Wu, Weibing; Yang, Weisheng; Liu, Congmin; Deng, Yulin; Chao, Zi-Sheng

    2018-06-19

    The utilization of biomass sugars has received great interesting recently. Herein, we present a highly efficient hybrid solar biomass fuel cell that utilizes thermal- and photocatalysis of solar irradiation and converts biomass sugars into electricity with high power output. The fuel cell uses polyoxometalates (POMs) as photocatalyst to decompose sugars and capture their electrons. The reduced POMs have strong visible and near-infrared light adsorption, which can significantly increase the temperature of the reaction system and largely promotes the thermal oxidation of sugars by the POM. In addition, the reduced POM functions as charge carrier that can release electrons at the anode in the fuel cell to generate electricity. The electron-transfer rates from glucose to POM under thermal and light-irradiation conditions were investigated in detail. The power outputs of this solar biomass fuel cell are investigated by using different types of sugars as fuels, with the highest power density reaching 45 mW cm -2 . © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Analysis of the Fuel Efficiency of a Hybrid Electric Drive with an Electric Power Splitter

    OpenAIRE

    D. Čundev

    2008-01-01

    This paper presents the results of an analysis of the fuel efficiency of a hybrid electric car drive, with an electric power splitter based on a double rotor synchronous permanent magnet generator. The results have been obtained through a precisely determined mathematical model and by simulating the characteristics of all essential values for the entire drive. This work is related to the experimental working stand for electric and hybrid car drive research, which has been developed at the Fac...

  12. An efficient method of fuel ice formation in moving free-standing ICF/IFE targets

    Science.gov (United States)

    Aleksandrova, I. V.; Bazdenkov, S. V.; Chtcherbakov, V. I.; Gromov, A. I.; Koresheva, E. R.; Koshelev, E. A.; Osipov, I. E.; Yaguzinskiy, L. S.

    2004-04-01

    Currently, research fields related to the elaboration of efficient layering methods for ICF/IFE applications are rapidly expanding. Significant progress has been made in the technology development based on rapid fuel layering inside moving free-standing targets (FST) which is referred to as the FST layering method. This paper presents our new results obtained in this area and describes technologically elegant solutions towards demonstrating a credible pathway for mass production of IFE cryogenic targets.

  13. An efficient method of fuel ice formation in moving free-standing ICF/IFE targets

    International Nuclear Information System (INIS)

    Aleksandrova, I V; Bazdenkov, S V; Chtcherbakov, V I; Gromov, A I; Koresheva, E R; Koshelev, E A; Osipov, I E; Yaguzinskiy, L S

    2004-01-01

    Currently, research fields related to the elaboration of efficient layering methods for ICF/IFE applications are rapidly expanding. Significant progress has been made in the technology development based on rapid fuel layering inside moving free-standing targets (FST) which is referred to as the FST layering method. This paper presents our new results obtained in this area and describes technologically elegant solutions towards demonstrating a credible pathway for mass production of IFE cryogenic targets

  14. The efficiency and fidelity of the in-core nuclear fuel management code FORMOSA-P

    International Nuclear Information System (INIS)

    Kropaczek, D.J.; Turinsky, P.J.

    1994-01-01

    The second-order generalized perturbation theory (GPT), nodal neutronic model utilized within the nuclear fuel management optimization code FORMOSA-P is presented within the context of prediction fidelity and computational efficiency versus forward solution. Key features of thr GPT neutronics model as implemented within the Simulated Annealing optimization adaptive control algorithm are discussed. Supporting results are then presented demonstrating the superior consistency of adaptive control for both global and local optimization searches. (authors). 15 refs., 1 fig., 4 tabs

  15. Marginal abatement cost curve for nitrogen oxides incorporating controls, renewable electricity, energy efficiency, and fuel switching.

    Science.gov (United States)

    Loughlin, Daniel H; Macpherson, Alexander J; Kaufman, Katherine R; Keaveny, Brian N

    2017-10-01

    A marginal abatement cost curve (MACC) traces out the relationship between the quantity of pollution abated and the marginal cost of abating each additional unit. In the context of air quality management, MACCs are typically developed by sorting control technologies by their relative cost-effectiveness. Other potentially important abatement measures such as renewable electricity, energy efficiency, and fuel switching (RE/EE/FS) are often not incorporated into MACCs, as it is difficult to quantify their costs and abatement potential. In this paper, a U.S. energy system model is used to develop a MACC for nitrogen oxides (NO x ) that incorporates both traditional controls and these additional measures. The MACC is decomposed by sector, and the relative cost-effectiveness of RE/EE/FS and traditional controls are compared. RE/EE/FS are shown to have the potential to increase emission reductions beyond what is possible when applying traditional controls alone. Furthermore, a portion of RE/EE/FS appear to be cost-competitive with traditional controls. Renewable electricity, energy efficiency, and fuel switching can be cost-competitive with traditional air pollutant controls for abating air pollutant emissions. The application of renewable electricity, energy efficiency, and fuel switching is also shown to have the potential to increase emission reductions beyond what is possible when applying traditional controls alone.

  16. Strategies for Efficient Charge Separation and Transfer in Artificial Photosynthesis of Solar Fuels.

    Science.gov (United States)

    Xu, Yuxing; Li, Ailong; Yao, Tingting; Ma, Changtong; Zhang, Xianwen; Shah, Jafar Hussain; Han, Hongxian

    2017-11-23

    Converting sunlight to solar fuels by artificial photosynthesis is an innovative science and technology for renewable energy. Light harvesting, photogenerated charge separation and transfer (CST), and catalytic reactions are the three primary steps in the processes involved in the conversion of solar energy to chemical energy (SE-CE). Among the processes, CST is the key "energy pump and delivery" step in determining the overall solar-energy conversion efficiency. Efficient CST is always high priority in designing and assembling artificial photosynthesis systems for solar-fuel production. This Review not only introduces the fundamental strategies for CST but also the combinatory application of these strategies to five types of the most-investigated semiconductor-based artificial photosynthesis systems: particulate, Z-scheme, hybrid, photoelectrochemical, and photovoltaics-assisted systems. We show that artificial photosynthesis systems with high SE-CE efficiency can be rationally designed and constructed through combinatory application of these strategies, setting a promising blueprint for the future of solar fuels. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Evaluation of fuel cell system efficiency and degradation at development and during commercialization

    Science.gov (United States)

    Gemmen, R. S.; Johnson, C. D.

    Two primary parameters stand out for characterizing fuel cell system performance. The first and most important parameter is system efficiency. This parameter is relatively easy to define, and protocols for its assessment are already available. Another important parameter yet to be fully considered is system degradation. Degradation is important because customers desire to know how long their purchased fuel cell unit will last. The measure of degradation describes this performance factor by quantifying, for example, how the efficiency of the unit degrades over time. While both efficiency and degradation concepts are readily understood, the coupling between these two parameters must also be understood so that proper testing and evaluation of fuel cell systems is achieved. Tests not properly performed, and results not properly understood, may result in improper use of the evaluation data, producing improper R&D planning decisions and financial investments. This paper presents an analysis of system degradation, recommends an approach to its measurement, and shows how these two parameters are related and how one can be "traded-off" for the other.

  18. Demonstration of improved vehicle fuel efficiency through innovative tire design, materials, and weight reduction technologies

    Energy Technology Data Exchange (ETDEWEB)

    Donley, Tim [Cooper Tire & Rubber Company Incorporated, Findlay, OH (United States)

    2014-12-31

    Cooper completed an investigation into new tire technology using a novel approach to develop and demonstrate a new class of fuel efficient tires using innovative materials technology and tire design concepts. The objective of this work was to develop a new class of fuel efficient tires, focused on the “replacement market” that would improve overall passenger vehicle fuel efficiency by 3% while lowering the overall tire weight by 20%. A further goal of this project was to accomplish the objectives while maintaining the traction and wear performance of the control tire. This program was designed to build on what has already been accomplished in the tire industry for rolling resistance based on the knowledge and general principles developed over the past decades. Cooper’s CS4 (Figure #1) premium broadline tire was chosen as the control tire for this program. For Cooper to achieve the goals of this project, the development of multiple technologies was necessary. Six technologies were chosen that are not currently being used in the tire industry at any significant level, but that showed excellent prospects in preliminary research. This development was divided into two phases. Phase I investigated six different technologies as individual components. Phase II then took a holistic approach by combining all the technologies that showed positive results during phase one development.

  19. Overall efficiencies for conversion of solar energy to a chemical fuel

    Science.gov (United States)

    Fish, J. D.

    A complete and consistent scheme for determining the overall efficiency of a generalized process for the conversion of solar energy into a chemical fuel (e.g. hydrogen) is developed and applied to seven conversion processes: thermal, thermochemical, photovoltaic, photogalvanic, photoelectrolysis, photosynthesis and photochemical conversion. It is demonstrated that the overall efficiency of each of these processes is determined by ten common factors: maximum theoretical efficiency, inherent absorption losses, inherent internal losses, rate limiting effects, reflection losses, transmission losses, coverage losses, system construction requirements, parasitic losses and harvesting and conversion losses. Both state-of-the-art and optimistic values are assigned to each factor for each of the seven conversion processes. State-of-the-art overall efficiencies ranged from 5% for thermal conversion down to essentially zero for thermochemical. Optimistic values in the range of about 10 to 15% are calculated for several of the processes.

  20. Scientific Assessment in support of the Materials Roadmap enabling Low Carbon Energy Technologies: Hydrogen and Fuel Cells

    DEFF Research Database (Denmark)

    Cerri, I.; Lefebvre-Joud, F.; Holtappels, Peter

    A group of experts from European research organisations and industry have assessed the state of the art and future needs for materials' R&D for hydrogen and fuel cell technologies. The work was performed as input to the European Commission's roadmapping exercise on materials for the European...

  1. Effects of water-emulsified fuel on a diesel engine generator's thermal efficiency and exhaust.

    Science.gov (United States)

    Syu, Jin-Yuan; Chang, Yuan-Yi; Tseng, Chao-Heng; Yan, Yeou-Lih; Chang, Yu-Min; Chen, Chih-Chieh; Lin, Wen-Yinn

    2014-08-01

    Water-emulsified diesel has proven itself as a technically sufficient improvement fuel to improve diesel engine fuel combustion emissions and engine performance. However, it has seldom been used in light-duty diesel engines. Therefore, this paper focuses on an investigation into the thermal efficiency and pollution emission analysis of a light-duty diesel engine generator fueled with different water content emulsified diesel fuels (WD, including WD-0, WD-5, WD-10, and WD-15). In this study, nitric oxide, carbon monoxide, hydrocarbons, and carbon dioxide were analyzed by a vehicle emission gas analyzer and the particle size and number concentration were measured by an electrical low-pressure impactor. In addition, engine loading and fuel consumption were also measured to calculate the thermal efficiency. Measurement results suggested that water-emulsified diesel was useful to improve the thermal efficiency and the exhaust emission of a diesel engine. Obviously, the thermal efficiency was increased about 1.2 to 19.9%. In addition, water-emulsified diesel leads to a significant reduction of nitric oxide emission (less by about 18.3 to 45.4%). However the particle number concentration emission might be increased if the loading of the generator becomes lower than or equal to 1800 W. In addition, exhaust particle size distributions were shifted toward larger particles at high loading. The consequence of this research proposed that the water-emulsified diesel was useful to improve the engine performance and some of exhaust emissions, especially the NO emission reduction. Implications: The accumulated test results provide a good basis to resolve the corresponding pollutants emitted from a light-duty diesel engine generator. By measuring and analyzing transforms of exhaust pollutant from this engine generator, the effects of water-emulsified diesel fuel and loading on emission characteristics might be more clear. Understanding reduction of pollutant emissions during the use

  2. Reactor fueling system

    International Nuclear Information System (INIS)

    Hattori, Noriaki; Hirano, Haruyoshi.

    1983-01-01

    Purpose: To optimally position a fuel catcher by mounting a television camera to a fuel catching portion and judging video images by the use of a computer or the like. Constitution: A television camera is mounted to the lower end of a fuel catching mechanism for handling nuclear fuels and a fuel assembly disposed within a reactor core or a fuel storage pool is observed directly from above to judge the position for the fuel assembly by means of video signals. Then, the relative deviation between the actual position of the fuel catcher and that set in a memory device is determined and the positional correction is carried out automatically so as to reduce the determined deviation to zero. This enables to catch the fuel assembly without failure and improves the efficiency for the fuel exchange operation. (Moriyama, K.)

  3. The effect of size-control policy on unified energy and carbon efficiency for Chinese fossil fuel power plants

    International Nuclear Information System (INIS)

    Zhang, Ning; Kong, Fanbin; Choi, Yongrok; Zhou, P.

    2014-01-01

    This paper examines the effect of size control policy on the energy and carbon efficiency for Chinese fossil fuel power industry. For this purpose, we propose two non-radial directional distance functions for energy/carbon efficiency analysis of fossil fuel electricity generation. One is named a total-factor directional distance function that incorporates the inefficiency of all input and output factors to measure the unified (operational and environmental) efficiency of fossil fuel power plants, and the other is called an energy–environmental directional distance function that can be used to measure the energy–environmental performance of fossil fuel electric power plants. Several standardized indicators for measuring unified efficiency and energy–environmental performance are derived from the two directional distance functions. An empirical study of 252 fossil fuel power plants in China is conducted by using the proposed approach. Our empirical results show that there exists a significant positive relationship between the plant size and unified efficiency, the five state-owned companies show lower unified efficiency and energy–environmental performance than other companies. It is suggested that Chinese government might need to consider private incentives and deregulation for its state-owned enterprises to improve their performance proactively. - Highlights: • Two non-radial directional distance functions are presented for energy/carbon efficiency analysis. • An empirical study of 252 fossil fuel power plants in China is conducted. • The five state-owned companies show lower unified efficiency and energy–environmental performance

  4. Waste plastics as supplemental fuel in the blast furnace process: improving combustion efficiencies.

    Science.gov (United States)

    Kim, Dongsu; Shin, Sunghye; Sohn, Seungman; Choi, Jinshik; Ban, Bongchan

    2002-10-14

    The possibility of using waste plastics as a source of secondary fuel in a blast furnace has been of recent interest. The success of this process, however, will be critically dependent upon the optimization of operating systems. For instance, the supply of waste plastics must be reliable as well as economically attractive compared with conventional secondary fuels such as heavy oil, natural gas and pulverized coal. In this work, we put special importance on the improvement of the combustibility of waste plastics as a way to enhance energy efficiency in a blast furnace. As experimental variables to approach this target, the effects of plastic particle size, blast temperature, and the level of oxygen enrichment were investigated using a custom-made blast model designed to simulate a real furnace. Lastly, the combustion efficiency of the mixture of waste plastics and pulverized coal was tested. The observations made from these experiments led us to the conclusion that with the increase of both blast temperature and the level of oxygen enrichment, and with a decrease in particle size, the combustibility of waste polyethylene could be improved at a given distance from the tuyere. Also it was found that the efficiency of coal combustion decreased with the addition of plastics; however, the combustion efficiency of mixture could be comparable at a longer distance from the tuyere.

  5. Enhanced Emission Performance and Fuel Efficiency for HD Methane Engines. Literature Study. Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Broman, R.; Staalhammar, P.; Erlandsson, L.

    2010-05-15

    A literature survey has been conducted in order to define state-of-the-art for methane fuelled engines to be used in heavy duty vehicles. Use of methane can be favourable to increase security of supply and mitigate CO2 emissions, especially when the methane origins from biomass. Furthermore, methane used as a fuel in heavy duty engines has a potential to reduce toxic exhaust emissions. Historically, use of methane in heavy duty engines has often been hampered by poor efficiency, i.e. high fuel consumption when using the Otto-cycle. However, current generation technology engines might be within 5-10 % of the efficiency of Diesel engine technology. In this context it is worth mentioning that compliance-driven changes for meeting future emission regulations for Diesel engines may have a negative impact on fuel efficiency, thereby narrowing the gap. This may present an opportunity for heavy methane fuelled engines. The reliability and durability of the exhaust aftertreatment devices for methane fuelled engines has also given rise to some concerns. Some concepts are performing acceptable while others do not meet expectations. This is partly due to difficulties in handling methane in the aftertreatment device and partly to issues in the design of the ignition system. Methane is a fuel used worldwide and has a potential to be an important complement to Diesel oil. There are two categories of HD methane engines available to end-users: Retrofitted engines, which often include computer controlled retrofit systems developed as 'bolt-on' technologies that can be removed if necessary, to resell the vehicle with a normal diesel engine, and those developed specifically for and in conjunction with engine manufacturers and delivered to customers as factory-built engines or vehicles (OEM). Additionally, both these categories can include engines that use the Otto- or Diesel combustion cycles. When adapting a HD Diesel engine to run on methane there are two options, either

  6. REVA Advanced Fuel Design and Codes and Methods - Increasing Reliability, Operating Margin and Efficiency in Operation

    Energy Technology Data Exchange (ETDEWEB)

    Frichet, A.; Mollard, P.; Gentet, G.; Lippert, H. J.; Curva-Tivig, F.; Cole, S.; Garner, N.

    2014-07-01

    Since three decades, AREVA has been incrementally implementing upgrades in the BWR and PWR Fuel design and codes and methods leading to an ever greater fuel efficiency and easier licensing. For PWRs, AREVA is implementing upgraded versions of its HTP{sup T}M and AFA 3G technologies called HTP{sup T}M-I and AFA3G-I. These fuel assemblies feature improved robustness and dimensional stability through the ultimate optimization of their hold down system, the use of Q12, the AREVA advanced quaternary alloy for guide tube, the increase in their wall thickness and the stiffening of the spacer to guide tube connection. But an even bigger step forward has been achieved a s AREVA has successfully developed and introduces to the market the GAIA product which maintains the resistance to grid to rod fretting (GTRF) of the HTP{sup T}M product while providing addition al thermal-hydraulic margin and high resistance to Fuel Assembly bow. (Author)

  7. Induced motor vehicle travel from improved fuel efficiency and road expansion

    Energy Technology Data Exchange (ETDEWEB)

    Su Qing, E-mail: suq1@nku.edu [Department of Marketing, Economics and Sports Business, Northern Kentucky University, AST Center, Office 338, Nunn Drive, Highland Heights, KY 41099 (United States)

    2011-11-15

    This paper investigates the impact of improved fuel efficiency and road network expansion on motor vehicle travel using a system dynamic panel data estimator and panel data at the state level for the 2001-2008 period. Our model accounts for endogenous changes in fuel efficiency, congestion, fuel cost per mile, and vehicle stock. Our regression results suggest that the short run rebound effect is 0.0276 while the long run rebound effect is 0.11. The short run effect of road capacity per capita is 0.066 while the long run effect is 0.26. - Highlights: > We estimate two effects: the rebound effect and induced travel effect at the state level. > System dynamic panel data approach is used to address endogeneity issue. > In the period of 2001-2008, the rebound effect is 0.0276 in the short run and 0.11 in the long run. > Increase in road capacity induces motor vehicle travel. > Induced travel effect is 0. 0.066 in the short run and 0.26 in the long run.

  8. Induced motor vehicle travel from improved fuel efficiency and road expansion

    International Nuclear Information System (INIS)

    Su Qing

    2011-01-01

    This paper investigates the impact of improved fuel efficiency and road network expansion on motor vehicle travel using a system dynamic panel data estimator and panel data at the state level for the 2001-2008 period. Our model accounts for endogenous changes in fuel efficiency, congestion, fuel cost per mile, and vehicle stock. Our regression results suggest that the short run rebound effect is 0.0276 while the long run rebound effect is 0.11. The short run effect of road capacity per capita is 0.066 while the long run effect is 0.26. - Highlights: → We estimate two effects: the rebound effect and induced travel effect at the state level. → System dynamic panel data approach is used to address endogeneity issue. → In the period of 2001-2008, the rebound effect is 0.0276 in the short run and 0.11 in the long run. → Increase in road capacity induces motor vehicle travel. → Induced travel effect is 0. 0.066 in the short run and 0.26 in the long run.

  9. Improved heavy-duty vehicle fuel efficiency in India, benefits, costs and environmental impacts

    Energy Technology Data Exchange (ETDEWEB)

    Gopal, Anand R. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Karali, Nihan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sharpe, Ben [International Council on Clean Transportation (United States); Delgado, Oscar [International Council on Clean Transportation (United States); Bandivadekar, Anup [International Council on Clean Transportation (United States); Garg, Mehul [International Council on Clean Transportation (United States)

    2017-06-14

    The main objectives of this analysis are to examine the benefits and costs of fuel-saving technologies for new heavy-duty vehicles (HDVs) in India over the next 10 years and, to explore how various scenarios for the deployment of vehicles with these technologies will impact petroleum consumption and carbon dioxide (CO2) emissions over the next three decades. The study team developed simulation models for three representative HDV types—a 40-tonne tractor-trailer, 25-tonne rigid truck, and 16-tonne transit bus—based on top-selling vehicle models in the Indian market. The baseline technology profiles for all three vehicles were developed using India-specific engine data and vehicle specification information from manufacturer literature and input from industry experts. For each of the three vehicles we developed a comprehensive set of seven efficiency technology packages drawing from five major areas: engine, transmission and driveline, tires, aerodynamics, and weight reduction. Our analysis finds that India has substantial opportunity to improve HDV fuel efficiency levels using cost-effective technologies. Results from our simulation modeling of three representative HDV types—a tractor-trailer, rigid truck, and transit bus—reveal that per-vehicle fuel consumption reductions between roughly 20% and 35% are possible with technologies that provide a return on the initial capital investment within 1 to 2 years. Though most of these technologies are currently unavailable in India, experiences in other more advanced markets such as the US and EU suggest that with sufficient incentives and robust regulatory design, significant progress can be made in developing and deploying efficiency technologies that can provide real-world fuel savings for new commercial vehicles in India over the next 10 years. Bringing HDVs in India up to world-class technology levels will yield substantial petroleum and GHG reductions. By 2030, the fuel and CO2 reductions of the

  10. The influence of the types of marine fuel over the Energy Efficiency Operational Index

    Science.gov (United States)

    Acomi, Nicoleta; Acomi, Ovidiu

    2014-05-01

    One of the main concerns of our society is certainly the environment protection. The international efforts for maintaining the environment clean are various and this paper refers to the efforts in the maritime transport field. Marine pollution consists of the water pollution and also the air pollution. Regardless of the delay in recognizing the later type of pollution, it rapidly gains many organizations to argue on it. The first step was including a dedicated annex (Annex VI) in the International Convention for the Prevention of Pollution from Ships, in 1997, which seeks to minimize the airborne emissions from ships. In order to control and minimize the air pollution, the International Maritime Organization has also developed a series of measures for monitoring the emissions. These measures are grouped in three main directions: technical, operational and management related. The subject of our study is the concept of Energy Efficiency Operational Index (EEOI), developed to provide ship-owners with assistance in the process of establishing the emissions from ships in operation, and to suggest the methods for achieving their reduction. As a monitoring tool, EEOI represents the mass of CO2 emitted per unit of transport work. The actual CO2 emission from combustion of fuel on board a ship during each voyage is calculated by multiplying total fuel consumption for each type of fuel (e.g. diesel oil, gas oil, light fuel oil, heavy fuel oil, liquefied petroleum gas, liquefied natural gas) with the carbon to CO2 conversion factor for the fuel in question. The performed transport work is calculated by multiplying mass of cargo (tonnes, number of TEU/cars, or number of passengers) with the distance in nautical miles corresponding to the transport work done. Using the software developed by the author it will be emphasized the variation of the EEOI value for one vessel using different types of fuel for the voyage's legs (distance to discharge port, distance to loading port, the

  11. 77 FR 51499 - Greenhouse Gas Emissions Standards and Fuel Efficiency Standards for Medium- and Heavy-Duty...

    Science.gov (United States)

    2012-08-24

    ... DEPARTMENT OF TRANSPORTATION National Highway Traffic Safety Administration 49 CFR Part 535 [NHTSA 2012-0126] RIN 2127-AK74 Greenhouse Gas Emissions Standards and Fuel Efficiency Standards for Medium... purpose of reducing greenhouse gas (GHG) emissions because the GHG standards fundamentally regulate fuel...

  12. 76 FR 59922 - Greenhouse Gas Emissions Standards and Fuel Efficiency Standards for Medium- and Heavy-Duty...

    Science.gov (United States)

    2011-09-28

    ... DEPARTMENT OF TRANSPORTATION National Highway Traffic Safety Administration 49 CFR Part 535 [NHTSA 2010-0079; EPA-HQ-OAR-2010-0162; FRL-9455-1] RIN 2127-AK74 Greenhouse Gas Emissions Standards and Fuel... comprehensive Heavy-Duty National Program that will increase fuel efficiency and reduce greenhouse gas emissions...

  13. Apparatus and method for enabling quantum-defect-limited conversion efficiency in cladding-pumped Raman fiber lasers

    Science.gov (United States)

    Heebner, John E.; Sridharan, Arun K.; Dawson, Jay Walter; Messerly, Michael J.; Pax, Paul H.

    2016-09-20

    Cladding-pumped Raman fiber lasers and amplifiers provide high-efficiency conversion efficiency at high brightness enhancement. Differential loss is applied to both single-pass configurations appropriate for pulsed amplification and laser oscillator configurations applied to high average power cw source generation.

  14. Heterobimetallic Zeolite, InV-ZSM-5, Enables Efficient Conversion of Biomass Derived Ethanol to Renewable Hydrocarbons.

    Science.gov (United States)

    Narula, Chaitanya K; Li, Zhenglong; Casbeer, Erik M; Geiger, Robert A; Moses-Debusk, Melanie; Keller, Martin; Buchanan, Michelle V; Davison, Brian H

    2015-11-03

    Direct catalytic conversion of ethanol to hydrocarbon blend-stock can increase biofuels use in current vehicles beyond the ethanol blend-wall of 10-15%. Literature reports describe quantitative conversion of ethanol over zeolite catalysts but high C2 hydrocarbon formation renders this approach unsuitable for commercialization. Furthermore, the prior mechanistic studies suggested that ethanol conversion involves endothermic dehydration step. Here, we report the complete conversion of ethanol to hydrocarbons over InV-ZSM-5 without added hydrogen and which produces lower C2 (dehydration step is not necessary. Thus, our method of direct conversion of ethanol offers a pathway to produce suitable hydrocarbon blend-stock that may be blended at a refinery to produce fuels such as gasoline, diesel, JP-8, and jet fuel, or produce commodity chemicals such as BTX.

  15. Development of structural materials to enable the electrochemical reduction of spent oxide nuclear fuel in a molten salt electrolyte

    Energy Technology Data Exchange (ETDEWEB)

    Hur, J. M.; Cho, S. H.; Lim, J. H.; Seo, C. S.; Park, S. W

    2006-02-15

    For the development of the advanced spent fuel management process based on the molten salt technology, it is essential to choose the optimum material for the process equipment handling a molten salt. In this study, corrosion behavior of Fe-base superalloy, Ni-base superalloy, non-metallic material and surface modified superalloy were investigated in the hot molten salt under oxidation atmosphere. These experimental data will suggest a guideline for the selection of corrosion resistant materials and help to find the operation criteria of each equipment in aspects of high temperature characteristics and corrosion retardation.

  16. Avoided emissions of a fuel-efficient biomass cookstove dwarf embodied emissions

    Directory of Open Access Journals (Sweden)

    D.L. Wilson

    2016-06-01

    Full Text Available Three billion people cook their food on biomass-fueled fires. This practice contributes to the anthropogenic radiative forcing. Fuel-efficient biomass cookstoves have the potential to reduce CO2-equivalent emissions from cooking, however, cookstoves made from modern materials and distributed through energy-intensive supply chains have higher embodied CO2-equivalent than traditional cookstoves. No studies exist examining whether lifetime emissions savings from fuel-efficient biomass cookstoves offset embodied emissions, and if so, by what margin. This paper is a complete life cycle inventory of “The Berkeley–Darfur Stove,” disseminated in Sudan by the non-profit Potential Energy. We estimate the embodied CO2-equivalent in the cookstove associated with materials, manufacturing, transportation, and end-of-life is 17 kg of CO2-equivalent. Assuming a mix of 55% non-renewable biomass and 45% renewable biomass, five years of service, and a conservative 35% reduction in fuel use relative to a three-stone fire, the cookstove will offset 7.5 tonnes of CO2-equivalent. A one-to-one replacement of a three-stone fire with the cookstove will save roughly 440 times more CO2-equivalent than it “costs” to create and distribute. Over its five-year life, we estimate the total use-phase emissions of the cookstove to be 13.5 tonnes CO2-equivalent, and the use-phase accounts for 99.9% of cookstove life cycle emissions. The dominance of use-phase emissions illuminate two important insights: (1 without a rigorous program to monitor use-phase emissions, an accurate estimate of life cycle emissions from biomass cookstoves is not possible, and (2 improving a cookstove's avoided emissions relies almost exclusively on reducing use-phase emissions even if use-phase reductions come at the cost of substantially increased non-use-phase emissions.

  17. Furnace devices aerodynamics optimization for fuel combustion efficiency improvement and nitrogen oxide emission reduction

    Science.gov (United States)

    Volkov, E. P.; Prokhorov, V. B.; Arkhipov, A. M.; Chernov, S. L.; Kirichkov, V. S.; Kaverin, A. A.

    2017-11-01

    MPEI conducts researches on physical and mathematical models of furnace chambers for improvement of power-generation equipment fuel combustion efficiency and ecological safety. Results of these researches are general principles of furnace aerodynamics arrangement for straight-flow burners and various fuels. It has been shown, that staged combustion arrangement with early heating and igniting with torch distribution in all furnace volume allows to obtain low carbon in fly ash and nitrogen oxide emission and also to improve boiler operation reliability with expand load adjustment range. For solid fuel combustion efficiency improvement it is practical to use high-placed and strongly down-tilted straight-flow burners, which increases high-temperature zone residence time for fuel particles. In some cases, for this combustion scheme it is possible to avoid slag-tap removal (STR) combustion and to use Dry-bottom ash removal (DBAR) combustion with tolerable carbon in fly ash level. It is worth noting that boilers with STR have very high nitrogen oxide emission levels (1200-1800 mg/m3) and narrow load adjustment range, which is determined by liquid slag output stability, so most industrially-developed countries don’t use this technology. Final decision about overhaul of boiler unit is made with regard to physical and mathematical modeling results for furnace and zonal thermal calculations for furnace and boiler as a whole. Overhaul of boilers to provide staged combustion and straight-flow burners and nozzles allows ensuring regulatory nitrogen oxide emission levels and corresponding best available technology criteria, which is especially relevant due to changes in Russian environmental regulation.

  18. Back-end fuel cycle efficiencies with respect to improved uranium utilization

    International Nuclear Information System (INIS)

    Kuczera, B.; Hennies, H.H.

    1983-01-01

    The world-wide nuclear power plant (NPP) capacity is at present 160 GW(e). If one adds the power stations under construction and ordered, a plant capacity of approximately 480 GW(e) is obtained for 1990, with the share of LWRs making up more than 80%. A modern LWR consumes in the open fuel cycle about 4400 metric tonnes of natural uranium per GW(e), assuming a lifetime of 30 years and a load factor of 70%. Considering the natural uranium reserves known at present and exploitable under economic conditions, it can be conveniently estimated that, with the present NPP capacity extension perspective, the natural uranium resources may be exhausted in a few decades. This trend can be counteracted in a flexible manner by various approaches in fuel cycle technology and strategy: (i) by steady further development of the established LWR technology the uranium consumption can be reduced by about 15%; (ii) closing the nuclear fuel cycle on the basis of LWRs (i.e. thermal uranium and plutonium recycling) implies up to 40% savings in natural uranium consumption; (iii) more recent considerations include the advanced pressurized water reactor (APWR). The APWR combines the proven PWR technology with a newly developed tight lattice core with greatly improved conversion characteristics (conversion ratio = 0.90 to 0.95). In terms of uranium utilization, the APWR has an efficiency three to five times higher than a PWR; (iv) Commercial introduction of FBR systems results in an optimal utilization of uranium which, at the same time, guarantees the supply of nuclear fuel well beyond the present century. For a corresponding transition period an energy supply system can be conceived which relies essentially on extended back-end fuel cycle capacities. These would facilitate a symbiosis of PWR, APWR and FBR, characterized by high flexibility with respect to long-term developments on the energy market. (author)

  19. State and Alternative Fuel Provider Fleets Alternative Compliance; U.S. Department of Energy (DOE), Energy Efficiency & Renewable Energy (EERE)

    Energy Technology Data Exchange (ETDEWEB)

    None

    2015-08-01

    The final rule of the Energy Policy Act of 2005 and its associated regulations enable covered state and alternative fuel provider fleets to obtain waivers from the alternative fuel vehicle (AFV)-acquisition requirements of Standard Compliance. Under Alternative Compliance, covered fleets instead meet a petroleum-use reduction requirement. This guidance document is designed to help fleets better understand the Alternative Compliance option and successfully complete the waiver application process.

  20. Modulated diesel fuel injection strategy for efficient-clean utilization of low-grade biogas

    International Nuclear Information System (INIS)

    Wang, Xiaole; Qian, Yong; Zhou, Qiyan; Lu, Xingcai

    2016-01-01

    Highlights: • Influences of direct injection strategy on biogas RCCI mode are researched. • Excessive early pilot injection timing leads to the retard of combustion. • Overall indicated thermal efficiency of low-grade biogas can be higher than 40%. • Pilot injection timing has strong influence on particle size distribution. • Composition of biogas has a great influence on the gas emissions. - Abstract: Recently, as a kind of renewable fuel, low-grade biogas has been researched to apply in internal combustion engine. In this paper, an experimental study was conducted to study the influence of injection strategies on the efficient utilization of low-grade biogas in Reactivity Controlled Compression Ignition (RCCI) mode with port fuel injection of biogas and in-cylinder direct injection of diesel based on a modified electronic controlled high-pressure directly injected compression ignition engine. Considered the high proportion of inert gas in biogas, a four-components simulated gas (H_2:CO:CH_4:N_2 = 5:40:5:50 vol%) has been selected as test fuels to simulate biogas. The effects of several injection control parameters such as pilot injection timing, main injection timing, common rail pressure and pilot injection ratio on the combustion and emissions are analyzed in detail. The research demonstrates that the main injection timing can effectively control the combustion phase and excessive early pilot injection timing leads to retard of combustion. CO emissions are relatively high due to homogenous charge of biogas. NOx and smoke emissions can be effectively controlled. In RCCI mode, the indicated thermal efficiency of biogas/diesel can reach 40%.

  1. Enhancing instruction in Fuels and Combustion Laboratory via a developed computer-assisted program for establishing efficient coal-diesel oil mixture (CDOM) fuel proportions

    Energy Technology Data Exchange (ETDEWEB)

    Maglaya, A.B. [La Salle University, Manila (Philippines). Dept. of Mechanical Engineering

    2004-07-01

    This paper discusses the relevance of digital computation in Fuels and Combustion Laboratory experiments used by the senior students of the Department of Mechanical Engineering, De La Salle University-Manila, Philippines. One of the students' experiments involved the determination of the most efficient CDOM fuel proportion as alternative fuel to diesel oil for steam generators and other industrial applications. Theoretical calculations show that it requires tedious and repetitive computations. A computer-assisted program was developed to lessen the time-consuming activities. The formulation of algorithms were based on the system of equations of the heat interaction between the CDOM fuel, combustion air and products of combustion and by applying the principles of mass and energy equations (or the First Law of Thermodynamics) for reacting systems were utilized. The developed computer-assisted program output verified alternative fuel selected through actual experimentation.

  2. Probabilistic analysis of the efficiency of the damping devices against nuclear fuel container falling

    Science.gov (United States)

    Králik, Juraj

    2017-07-01

    The paper presents the probabilistic and sensitivity analysis of the efficiency of the damping devices cover of nuclear power plant under impact of the container of nuclear fuel of type TK C30 drop. The finite element idealization of nuclear power plant structure is used in space. The steel pipe damper system is proposed for dissipation of the kinetic energy of the container free fall. The experimental results of the shock-damper basic element behavior under impact loads are presented. The Newmark integration method is used for solution of the dynamic equations. The sensitivity and probabilistic analysis of damping devices was realized in the AntHILL and ANSYS software.

  3. Analysis of the Fuel Efficiency of a Hybrid Electric Drive with an Electric Power Splitter

    Directory of Open Access Journals (Sweden)

    D. Čundev

    2008-01-01

    Full Text Available This paper presents the results of an analysis of the fuel efficiency of a hybrid electric car drive, with an electric power splitter based on a double rotor synchronous permanent magnet generator. The results have been obtained through a precisely determined mathematical model and by simulating the characteristics of all essential values for the entire drive. This work is related to the experimental working stand for electric and hybrid car drive research, which has been developed at the Faculty of Electrical Engineering (FEE at CTU in Prague. 

  4. Design of a fuel-efficient guidance system for a STOL aircraft

    Science.gov (United States)

    Mclean, J. D.; Erzberger, H.

    1981-01-01

    In the predictive mode, the system synthesizes a horizontal path from an initial aircraft position and heading to a desired final position and heading and then synthesizes a fuel-efficient speed-altitude profile along the path. In the track mode, the synthesized trajectory is reconstructed and tracked automatically. An analytical basis for the design of the system is presented and a description of the airborne computer implementation is given. A detailed discussion of the software, which should be helpful to those who use the actual software developed for these tests, is also provided.

  5. Thermal properties and burning efficiency of crude oils and refined fuel oil

    DEFF Research Database (Denmark)

    van Gelderen, Laurens; Alva, Wilson Ulises Rojas; Mindykowski, Pierrick Anthony

    2017-01-01

    The thermal properties and burning efficiencies of fresh and weathered crude oils and a refined fuel oil were studied in order to improve the available input data for field ignition systems for the in-situ burning of crude oil on water. The time to ignition, surface temperature upon ignition, heat......-cooled holder for a cone calorimeter under incident heat fluxes of 0, 5, 10, 20, 30, 40 and 50 kW/m2. The results clearly showed that the weathered oils were the hardest to ignite, with increased ignition times and critical heat fluxes of 5-10 kW/m2. Evaporation and emulsification were shown...

  6. Challenges of efficient and clean use of fossil fuels for power production

    Energy Technology Data Exchange (ETDEWEB)

    Vortmeyer, Nicolas; Zimmermann, Gerhard

    2010-09-15

    Constantly increasing resource efficiency together with the broad introduction of CCS technologies is fundamental for a continuous use of fossil fuels in power generation against the background of up-coming requirements for CO2 emission reduction. In principle, CCS means up-grading conventional power plant technology with proven CO2 removal processes. However, this leads to additional losses, auxiliary power demand and cost. System integration, development or at least adaption of components and processes are the main requirements in this context. Different technology solutions and recent developments will be addressed as well as challenges when implementing in demonstration projects.

  7. Progress on Enabling an Interactive Conversation Between Commercial Building Occupants and Their Building To Improve Comfort and Energy Efficiency: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Schott, M.; Scheib, J.; Long, N.; Fleming, K.; Benne, K.; Brackney, L.

    2012-06-01

    Many studies have reported energy savings after installing a dashboard, but dashboards provide neither individual feedback to the occupant nor the ability to report individual comfort. The Building Agent (BA) provides an interface to engage the occupant in a conversation with the building control system and the building engineer. Preliminary outcomes of the BA-enabled feedback loop are presented, and the effectiveness of the three display modes will be compared to other dashboard studies to baseline energy savings in future research.

  8. Properties and efficiency of a Pt/Al2O3 catalyst applied in a solid fuel thermo-accumulating furnace

    Directory of Open Access Journals (Sweden)

    SRDJAN BELOSEVIC

    2007-08-01

    Full Text Available A prototype of a solid fuel thermo-accumulating furnace has been developed. In order to achieve a higher combustion efficiency, a Pt/Al2O3 catalyst in the form of 3 ± 0.3 mm spheres was applied, which enabled further combustion of flue gases within the furnace. Experimental investigation of the influence of the catalyst on the conversion of CO has been done for different operation regimes and positions of the catalyst. Paper presents selected results regarding CO emission during wood and coal combustion. Investigations suggest a considerable effect of the catalyst and a strong influence of the catalyst position to CO emission reduction. The microstructure of the catalyst beads, characterized by selective chemisorption of CO, has shown the decrease of the number of Pt sites as a consequence of blockage by coke deposits formed during the combustion of solid fuel.

  9. Analyzing Residential End-Use Energy Consumption Data to Inform Residential Consumer Decisions and Enable Energy Efficiency Improvements

    Science.gov (United States)

    Carlson, Derrick R.

    While renewable energy is in the process of maturing, energy efficiency improvements may provide an opportunity to reduce energy consumption and consequent greenhouse gas emissions to bridge the gap between current emissions and the reductions necessary to prevent serious effects of climate change and will continue to be an integral part of greenhouse gas emissions policy moving forward. Residential energy is a largely untapped source of energy reductions as consumers, who wish to reduce energy consumption for monetary, environmental, and other reasons, face barriers. One such barrier is a lack of knowledge or understanding of how energy is consumed in a home and how to reduce this consumption effectively through behavioral and technological changes. One way to improve understanding of residential energy consumption is through the creation of a model to predict which appliances and electronics will be present and significantly contribute to the electricity consumption of a home on the basis of various characteristics of that home. The basis of this model is publically available survey data from the Residential Energy Consumption Survey (RECS). By predicting how households are likely to consume energy, homeowners, policy makers, and other stakeholders have access to valuable data that enables reductions in energy consumption in the residential sector. This model can be used to select homes that may be ripe for energy reductions and to predict the appliances that are the basis of these potential reductions. This work suggests that most homes in the U.S. have about eight appliances that are responsible for about 80% of the electricity consumption in that home. Characteristics such as census region, floor space, income, and total electricity consumption affect which appliances are likely to be in a home, however the number of appliances is generally around 8. Generally it takes around 4 appliances to reach the 50% threshold and 12 appliances to reach 90% of electricity

  10. Ionic liquids in proton exchange membrane fuel cells: Efficient systems for energy generation

    Energy Technology Data Exchange (ETDEWEB)

    Padilha, Janine C.; Basso, Juliana; da Trindade, Leticia G.; Martini, Emilse M.A.; de Souza, Michele O.; de Souza, Roberto F. [Institute of Chemistry, UFRGS, Av. Bento Goncalves 9500, Porto Alegre 91501-970, P.O. Box 15003 (Brazil)

    2010-10-01

    Proton exchange membrane fuel cells (PEMFCs) are used in portable devices to generate electrical energy; however, the efficiency of the PEMFC is currently only 40%. This study demonstrates that the efficiency of a PEMFC can be increased to 61% when 1-butyl-3-methylimidazolium tetrafluoroborate (BMI.BF{sub 4}) ionic liquid (IL) is used together with the membrane electrode assembly (MEA). The results for ionic liquids (ILs) 1-butyl-3-methylimidazolium chloride (BMI.Cl) and 1-butyl-3-methylimidazolium tetrafluoroborate (BMI.BF{sub 4}) in aqueous solutions are better than those obtained with pure water. The current and the power densities with IL are at least 50 times higher than those obtained for the PEMFC wetted with pure water. This increase in PEMFC performance can greatly facilitate the use of renewable energy sources. (author)

  11. Efficiency Improvement Opportunities for Light-Duty Natural-Gas-Fueled Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Staunton, R.H.; Thomas, J.F.

    1998-12-01

    The purpose of this report is to evaluate and make recommendations concerning technologies that promise to improve the efilciency of compressed natural gas (CNG) light-duty vehicles. Technical targets for CNG automotive technology given in the March 1998 OffIce of Advanced Automotive Technologies research and development plan were used as guidance for this effort. The technical target that necessitates this current study is to validate technologies that enable CNG light vehicles to have at least 10% greater - fuel economy (on a miles per gallon equivalent basis) than equivalent gasoline vehicles by 2006. Other tar- gets important to natural gas (NG) automotive technology and this study are to: (1) increase CNG vehicle range to 380 miles, (2) reduce the incremental vehicle cost (CNG vs gasoline) to $1500, and (3) meet the California ultra low-emission vehicle (ULEV) and Federal Tier 2 emission standards expected to be in effect in 2004.

  12. A MultiAir®/MultiFuel Approach to Enhancing Engine System Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Reese, Ronald [Chrysler Group LLC., Auburn Hills, MI (United States)

    2015-05-20

    FCA US LLC (formally known as Chrysler Group LLC, and hereinafter “Chrysler”) was awarded an American Recovery and Reinvestment Act (ARRA) funded project by the Department of Energy (DOE) titled “A MultiAir®/MultiFuel Approach to Enhancing Engine System Efficiency” (hereinafter “project”). This award was issued after Chrysler submitted a proposal for Funding Opportunity Announcement DE-FOA- 0000079, “Systems Level Technology Development, Integration, and Demonstration for Efficient Class 8 Trucks (SuperTruck) and Advanced Technology Powertrains for Light-Duty Vehicles (ATP-LD).” Chrysler started work on this project on June 01, 2010 and completed testing activities on August 30, 2014. Overall objectives of this project were; Demonstrate a 25% improvement in combined Federal Test Procedure (FTP) City and Highway fuel economy over a 2009 Chrysler minivan; Accelerate the development of highly efficient engine and powertrain systems for light-duty vehicles, while meeting future emissions standards; and Create and retain jobs in accordance with the American Recovery and Reinvestment Act of 2009

  13. STUDY OF ALTERNATIVE FUELS AND EFFECTS OF COMPRESSION RATIO ON THERMAL EFFICIENCY AND ENGINE POWER

    Directory of Open Access Journals (Sweden)

    Sarjito Sarjito

    2017-01-01

    Full Text Available This paper was a case study during the sabatical program at Kingston University London in February 2007. It has been studied by team of motorsport automotive department Kingston University London and it has been elaborated as a final project on Master Program. This study takes into account some of the issues surrounding the debate about alcohol fuels in Motorsport and the wider automotive sector and is primarily concerned to add data where there seems to be little existing research since Motorsport is a secretive business. Motorsport plays an important part in the automotive industry and is a sport enjoyed worldwide. Racing practice is regarded as using the best available resources and technology as it requires optimal performance. The racing arena gives engineers the opportunity to test valuable technological solutions to prove their merits. Therefore, racing is the natural starting point for introducing new technological solutions to the public and could lead to the wholesale conversion to renewable fuels to meet our automotive energy needs. Alcohol has unique properties that make superior in many ways to ordinary gasoline. The higher knock resistance allows for higher compression ratios to be utilized resulting in higher power outputs and thermal efficiency. The efficient use of energy is of growing concern in all spheres of life and the automotive sector needs to be front runner in these efforts.

  14. CANDU fuel cycle economic efficiency assessments using the IAEA-MESSAGE-V code

    International Nuclear Information System (INIS)

    Prodea, Iosif; Margeanu, Cristina Alice; Aioanei, Corina; Prisecaru, Ilie; Danila, Nicolae

    2007-01-01

    The main goal of the paper is to evaluate different electricity generation costs in a CANDU Nuclear Power Plant (NPP) using different nuclear fuel cycles. The IAEA-MESSAGE code (Model for Energy Supply Strategy Alternatives and their General Environmental Impacts) will be used to accomplish these assessments. This complex tool was supplied by International Atomic Energy Agency (IAEA) in 2002 at 'IAEA-Regional Training Course on Development and Evaluation of Alternative Energy Strategies in Support of Sustainable Development' held in Institute for Nuclear Research Pitesti. It is worthy to remind that the sustainable development requires satisfying the energy demand of present generations without compromising the possibility of future generations to meet their own needs. Based on the latest public information in the next 10-15 years four CANDU-6 based NPP could be in operation in Romania. Two of them will have some enhancements not clearly specified, yet. Therefore we consider being necessary to investigate possibility to enhance the economic efficiency of existing in-service CANDU-6 power reactors. The MESSAGE program can satisfy these requirements if appropriate input models will be built. As it is mentioned in the dedicated issues, a major inherent feature of CANDU is its fuel cycle flexibility. Keeping this in mind, some proposed CANDU fuel cycles will be analyzed in the paper: Natural Uranium (NU), Slightly Enriched Uranium (SEU), Recovered Uranium (RU) with and without reprocessing. Finally, based on optimization of the MESSAGE objective function an economic hierarchy of CANDU fuel cycles will be proposed. The authors used mainly public information on different costs required by analysis. (authors)

  15. Transient overexpression of DNA adenine methylase enables efficient and mobile genome engineering with reduced off-target effects

    DEFF Research Database (Denmark)

    Lennen, Rebecca; Nilsson Wallin, Annika; Pedersen, Margit

    2016-01-01

    Homologous recombination of single-stranded oligonucleotides is a highly efficient process for introducing precise mutations into the genome of E. coli and other organisms when mismatch repair (MMR) is disabled. This can result in the rapid accumulation of off-target mutations that can mask desir...

  16. High thermal efficiency and low emission performance of a methanol reformed gas fueled engine for hybrid electric vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Yamane, K.; Nakajima, Y.; Shudo, T.; Hiruma, M. [Musahi Inst. of Tech., Tokyo (Japan); Komatsu, H.; Takagi, Y. [Nissan Motor Co., Ltd., Yokosuka (Japan)

    2000-07-01

    An internal combustion engine (ICE) operation was carried out experimentally by using the mixture of air and fuel simulating the reformed gas as the fuel. It has been found that the engine can expectedly attain ultra-low emission and high thermal efficiency, namely 35% brake thermal efficiency in the basis of the low heat value of the theoretically reformed gas or 42% in the basis of the low heat value of methanol. By using the result for the estimation of the total thermal efficiency at the end of the motor output shaft of a hybrid electric vehicle, it has been found that the total thermal efficiency of the reformed gas engine system is 34% in case of a 120% energy increment and 33% in case of a 116% energy increment with a little higher NOx emission of 60 ppm while the counterpart of the fuel cell system is 34%. When the emission level for EZEV is required, the total thermal efficiency falls to 32% in case of a 120% energy increment and 31% in case of a 116% energy increment. From the points of the reliability proved by the long history, higher specific power and low cost, the internal combustion engine system with the thermal efficiency almost equal to that of the fuel cell (FC) system is further more practical when methanol is used as the fuel. (orig.)

  17. Efficiency-improving fossil fuel technologies for electricity generation: Data selection and trends

    Energy Technology Data Exchange (ETDEWEB)

    Lanzi, Elisa [Fondazione Eni Enrico Mattei (Italy); Verdolini, Elena, E-mail: elena.verdolini@feem.it [Fondazione Eni Enrico Mattei (Italy); Universita Cattolica, del Sacro Cuore di Milano (Italy); Hascic, Ivan [OECD Environment Directorate (France)

    2011-11-15

    This paper studies patenting dynamics in efficiency improving electricity generation technologies as an important indicator of innovation activity. We build a novel database of worldwide patent applications in efficiency-improving fossil fuel technologies for electricity generation and then analyse patenting trends over time and across countries. We find that patenting has mostly been stable over time, with a recent decreasing trend. OECD countries represent the top innovators and the top markets for technology. Some non-OECD countries, and particularly China, are also very active in terms of patenting activity in this sector. The majority of patents are first filed in OECD countries and only then in BRIC and other non-OECD countries. BRIC and other non-OECD countries apply for patents that are mostly marketed domestically, but BRIC countries represent important markets for patent duplication of OECD inventions. These results are indicative of significant technology transfer in the field of efficiency-improving technologies for electricity production. - Highlights: > We study innovation in efficiency-improving electricity generation technologies. > Relevant patents are identified and used as an indicator of innovation. > We show that there is significant technology transfer in this field. > Most patents are first filed in OECD countries and then in non-OECD countries. > Patents in non-OECD countries are mostly marketed domestically.

  18. Efficiency-improving fossil fuel technologies for electricity generation: Data selection and trends

    International Nuclear Information System (INIS)

    Lanzi, Elisa; Verdolini, Elena; Hascic, Ivan

    2011-01-01

    This paper studies patenting dynamics in efficiency improving electricity generation technologies as an important indicator of innovation activity. We build a novel database of worldwide patent applications in efficiency-improving fossil fuel technologies for electricity generation and then analyse patenting trends over time and across countries. We find that patenting has mostly been stable over time, with a recent decreasing trend. OECD countries represent the top innovators and the top markets for technology. Some non-OECD countries, and particularly China, are also very active in terms of patenting activity in this sector. The majority of patents are first filed in OECD countries and only then in BRIC and other non-OECD countries. BRIC and other non-OECD countries apply for patents that are mostly marketed domestically, but BRIC countries represent important markets for patent duplication of OECD inventions. These results are indicative of significant technology transfer in the field of efficiency-improving technologies for electricity production. - Highlights: → We study innovation in efficiency-improving electricity generation technologies. → Relevant patents are identified and used as an indicator of innovation. → We show that there is significant technology transfer in this field. → Most patents are first filed in OECD countries and then in non-OECD countries. → Patents in non-OECD countries are mostly marketed domestically.

  19. Integrated fuel processor development

    International Nuclear Information System (INIS)

    Ahmed, S.; Pereira, C.; Lee, S. H. D.; Krumpelt, M.

    2001-01-01

    The Department of Energy's Office of Advanced Automotive Technologies has been supporting the development of fuel-flexible fuel processors at Argonne National Laboratory. These fuel processors will enable fuel cell vehicles to operate on fuels available through the existing infrastructure. The constraints of on-board space and weight require that these fuel processors be designed to be compact and lightweight, while meeting the performance targets for efficiency and gas quality needed for the fuel cell. This paper discusses the performance of a prototype fuel processor that has been designed and fabricated to operate with liquid fuels, such as gasoline, ethanol, methanol, etc. Rated for a capacity of 10 kWe (one-fifth of that needed for a car), the prototype fuel processor integrates the unit operations (vaporization, heat exchange, etc.) and processes (reforming, water-gas shift, preferential oxidation reactions, etc.) necessary to produce the hydrogen-rich gas (reformate) that will fuel the polymer electrolyte fuel cell stacks. The fuel processor work is being complemented by analytical and fundamental research. With the ultimate objective of meeting on-board fuel processor goals, these studies include: modeling fuel cell systems to identify design and operating features; evaluating alternative fuel processing options; and developing appropriate catalysts and materials. Issues and outstanding challenges that need to be overcome in order to develop practical, on-board devices are discussed

  20. Principle Findings from Development of a Recirculated Exhaust Gas Intake Sensor (REGIS) Enabling Cost-Effective Fuel Efficiency Improvement

    Energy Technology Data Exchange (ETDEWEB)

    Schnabel, Claus [Robert Bosch LLC, Farmington Hills, MI (United States)

    2016-03-30

    Kick-off of the Bosch scope of work for the REGIS project started in October 2012. The primary work-packages included in the Bosch scope of work were the following: overall project management, development of the EGR sensor (design of sensor element, design of protection tube, and design of mounting orientation), development of EGR system control strategy, build-up of prototype sensors, evaluation of system performance with the new sensor and the new control strategy, long-term durability testing, and development of a 2nd generation sensor concept for continued technology development after the REGIS project. The University of Clemson was a partner with Bosch in the REGIS project. The Clemson scope of work for the REGIS project started in June 2013. The primary work-packages included in the Clemson scope of work were the following: development of EGR system control strategy, and evaluation of system performance with the new sensor and new control strategy. This project was split into phase I, phase II and phase III. Phase I work was completed by the end of June 2014 and included the following primary work packages: development of sensor technical requirements, assembly of engine testbench at Clemson, design concept for sensor housing, connector, and mounting orientation, build-up of EGR flow test benches at Bosch, and build-up of first sensor prototypes. Phase II work was completed by the end of June 2015 and included the following primary work pack ages: development of an optimizing function and demonstration of robustness of sensor, system control strategy implementation and initial validation, completion of engine in the loop testing of developed control algorithm, completion of sensor testing including characteristic line, synthetic gas test stand, and pressure dependency characterization, demonstration of benefits of control w/o sensing via simulation, development of 2nd generation sensor concept. Notable technical achievements from phase II were the following: publication of two new technical papers by Clemson detailing the control strategies used for the EGR system control. The two papers was published in the 2016 SAE World Congress in April 2016. The titles of each paper are, “Physics-Based Exhaust Pressure and Temperature Estimation for Low Pressure EGR Control in Turbocharged Gasoline Engines,” by K. Siokos, and “A Control Algorithm for Low Pressure – EGR Systems using a Smith Predictor with Intake Oxygen Sensor Feedback”, by R. Koli. All phase III work packages have been completed. The primary work packages in phase III were the following: completion of long-term sensor durability testing, final demonstration of benefits of EGR control w/o sensing, final decision of the second generation sensor development path.

  1. Enabling the Distributed Generation Market of High Temperature Fuel Cell and Absorption Chiller Systems to Support Critical and Commercial Loads

    Science.gov (United States)

    DiMola, Ashley M.

    Buildings account for over 18% of the world's anthropogenic Greenhouse Gas (GHG) emissions. As a result, a technology that can offset GHG emissions associated with buildings has the potential to save over 9 Giga-tons of GHG emissions per year. High temperature fuel cell and absorption chiller (HTFC/AC) technology offers a relatively low-carbon option for meeting cooling and electric loads for buildings while producing almost no criteria pollutants. GHG emissions in the state of California would decrease by 7.48 million metric tons per year if every commercial building in the State used HTFC/AC technology to meet its power and cooling requirements. In order to realize the benefits of HTFC/AC technology on a wide scale, the distributed generation market needs to be exposed to the technology and informed of its economic viability and real-world potential. This work characterizes the economics associated with HTFC/AC technology using select scenarios that are representative of realistic applications. The financial impacts of various input factors are evaluated and the HTFC/AC simulations are compared to the economics of traditional building utilities. It is shown that, in addition to the emissions reductions derived from the systems, HTFC/AC technology is financially preferable in all of the scenarios evaluated. This work also presents the design of a showcase environment, centered on a beta-test application, that presents (1) system operating data gathered using a custom data acquisition module, and (2) HTFC/AC technology in a clear and approachable manner in order to serve the target audience of market stakeholders.

  2. Large area flexible polymer solar cells with high efficiency enabled by imprinted Ag grid and modified buffer layer

    International Nuclear Information System (INIS)

    Lu, Shudi; Lin, Jie; Liu, Kong; Yue, Shizhong; Ren, Kuankuan; Tan, Furui; Wang, Zhijie; Jin, Peng; Qu, Shengchun; Wang, Zhanguo

    2017-01-01

    To take a full advantage of polymer semiconductors on realization of large-area flexible photovoltaic devices, herein, we fabricate polymer solar cells on the basis of polyethylene terephthalate (PET) with imprinted Ag grid as transparent electrode. The key fabrication procedure is the adoption of a modified PEDOT:PSS (PH1000) solution for spin-coating the buffer layer to form a compact contact with the substrate. In comparison with the devices with intrinsic PEDOT:PSS buffer layer, the advanced devices present a much higher efficiency of 6.51%, even in a large device area of 2.25 cm"2. Subsequent characterizations reveal that such devices show an impressive performance stability as the bending angle is enlarged to 180° and bending time is up to 1000 cycles. Not only providing a general methodology to construct high efficient and flexible polymer solar cells, this paper also involves deep insights on device working mechanism in bending conditions.

  3. Poly(vinyl alcohol) separators improve the coulombic efficiency of activated carbon cathodes in microbial fuel cells

    KAUST Repository

    Chen, Guang

    2013-09-01

    High-performance microbial fuel cell (MFC) air cathodes were constructed using a combination of inexpensive materials for the oxygen reduction cathode catalyst and the electrode separator. A poly(vinyl alcohol) (PVA)-based electrode separator enabled high coulombic efficiencies (CEs) in MFCs with activated carbon (AC) cathodes without significantly decreasing power output. MFCs with AC cathodes and PVA separators had CEs (43%-89%) about twice those of AC cathodes lacking a separator (17%-55%) or cathodes made with platinum supported on carbon catalyst (Pt/C) and carbon cloth (CE of 20%-50%). Similar maximum power densities were observed for AC-cathode MFCs with (840 ± 42 mW/m2) or without (860 ± 10 mW/m2) the PVA separator after 18 cycles (36 days). Compared to MFCs with Pt-based cathodes, the cost of the AC-based cathodes with PVA separators was substantially reduced. These results demonstrated that AC-based cathodes with PVA separators are an inexpensive alternative to expensive Pt-based cathodes for construction of larger-scale MFC reactors. © 2013 Elsevier B.V. All rights reserved.

  4. ENTHALPY EU PROJECT: ENABLING THE DRYING PROCESS TO SAVE ENERGY AND WATER, REALISING PROCESS EFFICIENCY IN THE DAIRY CHAIN

    Directory of Open Access Journals (Sweden)

    Berta ALVAREZ PENEDO

    2016-11-01

    Full Text Available The EU funded ENTHALPY project aims to significantly reduce the consumption of water and energy in milk powder production to increase efficiency in the dairy production chain. Using a systematic approach, ENTHALPY project focusses on innovations within the post-harvest chain representing the highest energy and water consumption such as RF heating, solar thermal energy, mono-disperse atomising, dryer modelling, inline monitoring, enzymatic cleaning and membrane technology,

  5. ENTHALPY EU PROJECT: ENABLING THE DRYING PROCESS TO SAVE ENERGY AND WATER, REALISING PROCESS EFFICIENCY IN THE DAIRY CHAIN

    OpenAIRE

    Berta ALVAREZ PENEDO; Sandra FORSTNER; Alexandru RUSU

    2016-01-01

    The EU funded ENTHALPY project aims to significantly reduce the consumption of water and energy in milk powder production to increase efficiency in the dairy production chain. Using a systematic approach, ENTHALPY project focusses on innovations within the post-harvest chain representing the highest energy and water consumption such as RF heating, solar thermal energy, mono-disperse atomising, dryer modelling, inline monitoring, enzymatic cleaning and membrane technology,

  6. Poly(vinyl alcohol) separators improve the coulombic efficiency of activated carbon cathodes in microbial fuel cells

    KAUST Repository

    Chen, Guang; Zhang, Fang; Logan, Bruce E.; Hickner, Michael A.

    2013-01-01

    enabled high coulombic efficiencies (CEs) in MFCs with activated carbon (AC) cathodes without significantly decreasing power output. MFCs with AC cathodes and PVA separators had CEs (43%-89%) about twice those of AC cathodes lacking a separator (17

  7. Increase of efficiency and reliability of liquid fuel combustion in small-sized boilers

    Science.gov (United States)

    Roslyakov, P. V.; Proskurin, Yu V.; Ionkin, I. L.

    2017-11-01

    One of the ways to increase the efficiency of using fuels is to create highly efficient domestic energy equipment, in particular small-sized hot-water boilers in autonomous heating systems. Increasing the efficiency of the boiler requires a reduction in the temperature of the flue gases leaving, which, in turn, can be achieved by installing additional heating surfaces. The purpose of this work was to determine the principal design solutions and to develop a draft design for a high-efficiency 3-MW hot-water boiler using crude oil as its main fuel. Ensuring a high efficiency of the boiler is realized through the use of an external remote economizer, which makes it possible to reduce the dimensions of the boiler, facilitate the layout of equipment in a limited size block-modular boiler house and virtually eliminate low-temperature corrosion of boiler heat exchange surfaces. In the article the variants of execution of the water boiler and remote economizer are considered and the preliminary design calculations of the remote economizer for various schemes of the boiler layout in the Boiler Designer software package are made. Based on the results of the studies, a scheme was chosen with a three-way boiler and a two-way remote economizer. The design of a three-way fire tube hot water boiler and an external economizer with an internal arrangement of the collectors, providing for its location above the boiler in a block-modular boiler house and providing access for servicing both a remote economizer and a hot water boiler, is proposed. Its mass-dimensional and design parameters are determined. In the software package Boiler Designer thermal, hydraulic and aerodynamic calculations of the developed fire tube boiler have been performed. Optimization of the boiler design was performed, providing the required 94% efficiency value for crude oil combustion. The description of the developed flue and fire-tube hot water boiler and the value of the main design and technical and

  8. Fuel conversion efficiency and energy balance of a 400 kW{sub t} fluidized bed straw gasifier

    Energy Technology Data Exchange (ETDEWEB)

    Erguedenler, A.; Ghaly, A.E.; Hamdullahpur, F. [Technical Univ. of Nova Scotia, Halifax (Canada)

    1993-12-31

    A 400 kW (thermal) dual-distributor type fluidized bed gasifier developed for the energy recovery from cereal straw was used to investigate the effects of equivalence ratio (actual air-fuel ratio: stoichiometric air-fuel ratio), fluidization velocity and bed height on the fuel conversion efficiency from wheat straw. The energy balance was also performed on the system under those operating conditions. The results indicated that the equivalence ratio was the most significant parameter affecting the fuel conversion efficiency and the energy recovered from the straw in the form of gas. Both the fuel conversion efficiency and the energy recovery increased with increases in the equivalence ratio. The fluidization velocity and bed height had minimal effects on these parameters. A fuel conversion efficiency as high as 98% was obtained at the equivalence ratio of 0.35. The energy recovered in the form of gas and the sensible heat of the produced gas were in the ranges of 40--70% and 9--17%, respectively. Unaccounted losses showed a dramatic increase at lower equivalence ratios and were in the range of 6--53% depending on the operating condition.

  9. Fuel cell-based CHP system modelling using Artificial Neural Networks aimed at developing techno-economic efficiency maximization control systems

    International Nuclear Information System (INIS)

    Asensio, F.J.; San Martín, J.I.; Zamora, I.; Garcia-Villalobos, J.

    2017-01-01

    This paper focuses on the modelling of the performance of a Polymer Electrolyte Membrane Fuel Cell (PEMFC)-based cogeneration system to integrate it in hybrid and/or connected to grid systems and enable the optimization of the techno-economic efficiency of the system in which it is integrated. To this end, experimental tests on a PEMFC-based cogeneration system of 600 W of electrical power have been performed to train an Artificial Neural Network (ANN). Once the learning of the ANN, it has been able to emulate real operating conditions, such as the cooling water out temperature and the hydrogen consumption of the PEMFC depending on several variables, such as the electric power demanded, temperature of the inlet water flow to the cooling circuit, cooling water flow and the heat demanded to the CHP system. After analysing the results, it is concluded that the presented model reproduces with enough accuracy and precision the performance of the experimented PEMFC, thus enabling the use of the model and the ANN learning methodology to model other PEMFC-based cogeneration systems and integrate them in techno-economic efficiency optimization control systems. - Highlights: • The effect of the energy demand variation on the PEMFC's efficiency is predicted. • The model relies on experimental data obtained from a 600 W PEMFC. • It provides the temperature and the hydrogen consumption with good accuracy. • The range in which the global energy efficiency could be improved is provided.

  10. Efficiency improvement of nuclear power plant operation: the significant role of advanced nuclear fuel technologies

    International Nuclear Information System (INIS)

    Van Velde, AA. de; Burtak, F.

    2000-01-01

    In this paper authors deals with nuclear fuel cycle and their economic aspects. At Siemens, the developments focusing on the reduction of fuel cycle costs are currently directed on .further batch average burnup increase, .improvement of fuel reliability, .enlargement of fuel operation margins, .improvement of methods for fuel design and core analysis. These items will be presented in detail in the full paper and illustrated by the global operating experience of Siemens fuel for both PWRs and BWRs. (authors)

  11. Innovation-enabling policy and regime transformation towards increased energy efficiency: The case of the circulator pump industry in Europe

    DEFF Research Database (Denmark)

    Ruby, Tobias Møller

    2015-01-01

    When new energy efficient products are struggling with their commercialisation and diffusion into widespread applications you would typically expect policy-makers and green lead-users to guide the way. This paper examines the case of the hot water circulator pump industry in Europe, where parts...... of the industry envisioned and worked for a voluntary energy label, bringing technological innovation, new business and energy savings of approx. 85% for each new circulator pump. The case study explores the complexities of innovation processes where technology, market, actors and policy co-evolve over time...

  12. The relationship between income and personal vehicle fuel efficiency and associated equity concerns for the fuel tax.

    Science.gov (United States)

    2011-03-01

    The fuel tax, which is assessed on the physical amount of fuel purchased by the consumer, is the primary : means of funding roadway development at the state and national level. However, because it is assessed on a : gallon basis, drivers of vehicles ...

  13. Self-Powered Wireless Smart Sensor Node Enabled by an Ultrastable, Highly Efficient, and Superhydrophobic-Surface-Based Triboelectric Nanogenerator.

    Science.gov (United States)

    Zhao, Kun; Wang, Zhong Lin; Yang, Ya

    2016-09-27

    Wireless sensor networks will be responsible for a majority of the fast growth in intelligent systems in the next decade. However, most of the wireless smart sensor nodes require an external power source such as a Li-ion battery, where the labor cost and environmental waste issues of replacing batteries have largely limited the practical applications. Instead of using a Li-ion battery, we report an ultrastable, highly efficient, and superhydrophobic-surface-based triboelectric nanogenerator (TENG) to scavenge wind energy for sustainably powering a wireless smart temperature sensor node. There is no decrease in the output voltage and current of the TENG after continuous working for about 14 h at a wind speed of 12 m/s. Through a power management circuit, the TENG can deliver a constant output voltage of 3.3 V and a pulsed output current of about 100 mA to achieve highly efficient energy storage in a capacitor. A wireless smart temperature sensor node can be sustainably powered by the TENG for sending the real-time temperature data to an iPhone under a working distance of 26 m, demonstrating the feasibility of the self-powered wireless smart sensor networks.

  14. Improvement on performance and efficiency of direct methanol fuel cells using hydrocarbon-based membrane electrode assembly

    International Nuclear Information System (INIS)

    Kim, Joon-Hee; Yang, Min-Jee; Park, Jun-Young

    2014-01-01

    Highlights: • Faradaic efficiency and water transfer coefficient (WTC) of DMFC MEAs are calculated based on mass balance measurements. • Faradaic efficiency of the HC-based MEAs is generally improved over the Nafion-based MEAs. • Nafion-based MEAs show a WTC of 3, whereas the HC-based MEAs show a very low WTC of -2. • Low WTC of the HC-based MEAs indicates the back-diffusion of water from the cathode to the anode. • Performance of HC-based MEAs is improved as the fuel stoichiometry increases, maintaining high Faradaic efficiency. - Abstract: In order to improve the energy efficiency (fuel efficiency and electrical power) of direct methanol fuel cells (DMFCs), the hydrocarbon (HC) membrane-based membrane electrode assemblies (MEAs) are investigated under various operating conditions. The MEAs are then compared with the conventional Nafion-based MEA in terms of their efficiency and performance. The Faradaic efficiency and water transfer coefficient (WTC) are calculated based on mass balance measurements. The Faradaic efficiency of the HC-based MEAs is improved over the Nafion-based MEAs since methanol crossover decreased. The performance of HC-based MEAs shows strong dependency on the anode stoichiometry at high current densities probably because of the limited mass transport of fuel, which is not observed for the Nafion-based MEAs. The Nafion-based MEAs show a WTC of 3, whereas the HC-based MEAs show a very low WTC of −2, indicating the back-diffusion of water from the cathode to the anode. This may have limited mass transport by interrupting proton conduction at high current densities. The performance of HC-based MEAs at high current densities is improved as the fuel stoichiometry increases; High Faradaic efficiency is maintained by decreasing the cathode stoichiometry

  15. Enabling fast electron transfer through both bacterial outer-membrane redox centers and endogenous electron mediators by polyaniline hybridized large-mesoporous carbon anode for high-performance microbial fuel cells

    International Nuclear Information System (INIS)

    Zou, Long; Qiao, Yan; Zhong, Canyu; Li, Chang Ming

    2017-01-01

    Both physical structure and chemical property of an electrode play critical roles in extracellular electron transfer from microbes to electrodes in microbial fuel cells (MFCs). Herein a novel polyaniline hybridized large mesoporous carbon (PANI-LMC) anode is fabricated from natural biomass by nanostructured CaCO 3 template-assisted carbonization followed by in situ chemical polymerizing PANI to enable fast extracellular electron transfer, in which the LMC with rich disorder-interconnected large mesopores (∼20−50 nm) and large surface area facilitates a fast mediated electron transfer through electron mediators, while the decorated PANI on LMC surface enables the direct electron transfer via bacterial outer-membrane redox centers. Owing to the unique synergistic effect from both excellent electron transfer paths, the PANI-LMC hybrid anode harvests high power electricity with a maximum output power density of 1280 mW m −2 in Shewanella putrefaciens CN32 MFCs, 10-fold higher than that of conventional carbon cloth. The findings from this work suggest a new insight on design of high-efficient anode according to the multiple and flexible electrochemical process for practical MFC applications.

  16. ZTEK`s ultra-high efficiency fuel cell/gas turbine system for distributed generation

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, M.; Nathanson, D. [Ztek Corp., Waltham, MA (United States); Bradshaw, D.T. [Tennessee Valley Authority, Chattanooga, TN (United States)] [and others

    1996-12-31

    Ztek`s Planar Solid Oxide Fuel Cell (SOFC) system has exceptional potential for utility electric power generation because of: simplicity of components construction, capability for low cost manufacturing, efficient recovery of very high quality by-product heat (up to 1000{degrees}C), and system integration simplicity. Utility applications of the Solid Oxide Fuel Cell are varied and include distributed generation units (sub-MW to 30MW capacity), repowering existing power plants (i.e. 30MW to 100MW), and multi-megawatt central power plants. A TVA/EPRI collaboration program involved functional testing of the advanced solid oxide fuel cell stacks and design scale-up for distributed power generation applications. The emphasis is on the engineering design of the utility modules which will be the building blocks for up to megawatt scale power plants. The program has two distinctive subprograms: Verification test on a 1 kW stack and 25kW module for utility demonstration. A 1 kW Planar SOFC stack was successfully operated for 15,000 hours as of December, 1995. Ztek began work on a 25kW SOFC Power System for TVA, which plans to install the 25kW SOFC at a host site for demonstration in 1997. The 25kW module is Ztek`s intended building block for the commercial use of the Planar SOFC. Systems of up to megawatt capacity can be obtained by packaging the modules in 2-dimensional or 3-dimensional arrays.

  17. Enhanced fuel efficiency on tractor-trailers using synthetic jet-based active flow control

    Science.gov (United States)

    Amitay, Michael; Menicovich, David; Gallardo, Daniele

    2016-04-01

    The application of piezo-electrically-driven synthetic-jet-based active flow control to reduce drag on tractor-trailers was explored experimentally in wind tunnel testing as well as full-scale road tests. Aerodynamic drag accounts for more than 50% of the usable energy at highway speeds, a problem that applies primarily to trailer trucks. Therefore, a reduction in aerodynamic drag results in large saving of fuel and reduction in CO2 emissions. The active flow control technique that is being used relies on a modular system comprised of distributed, small, highly efficient actuators. These actuators, called synthetic jets, are jets that are synthesized at the edge of an orifice by a periodic motion of a piezoelectric diaphragm(s) mounted on one (or more) walls of a sealed cavity. The synthetic jet is zero net mass flux (ZNMF), but it allows momentum transfer to flow. It is typically driven near diaphragm and/or cavity resonance, and therefore, small electric input [O(10W)] is required. Another advantage of this actuator is that no plumbing is required. The system doesn't require changes to the body of the truck, can be easily reconfigured to various types of vehicles, and consumes small amounts of electrical power from the existing electrical system of the truck. Preliminary wind tunnel results showed up to 18% reduction in fuel consumption, whereas road tests also showed very promising results.

  18. Analysis of the efficiency and effectiveness of distributed generation in the power station (fuel) Sancti Spiritus

    International Nuclear Information System (INIS)

    Castro Álvarez, Alfredo; Pérez Pérez, Osvaldo; Bravo Amarante, Edelvy

    2015-01-01

    The severe crisis in the National Electric System (SEN) suffered by Cuba in the late 90's and early 2000 forced to change the design to keep the generation matrix supported in large plants towards where distributed generation small plants throughout the country, the state assumed demand and residential sector. From tools frequently used to evaluate the quality of processes (Scatter diagram, Pareto diagram, Ishikawa diagram and function quality loss Taguchi) was evaluated from indicators index fuel consumption and availability, efficiency and effectiveness of the generation process identifying areas within the plant that the greatest impact on the deviation of both indicators and the impact generated in the services, the economy and the environment. To develop this evaluation the operating data of the years 2012, 2013 and 2014 of the power plant were taken Sancti Spiritus. (full text)

  19. A phosphorus-free anolyte to enhance coulombic efficiency of microbial fuel cells

    Science.gov (United States)

    Tang, Xinhua; Li, Haoran; Du, Zhuwei; Ng, How Yong

    2014-12-01

    In this study, a phosphorus-free anolyte is prepared by using bicarbonate to replace phosphate buffer for application in two chamber microbial fuel cells (MFCs). Optical density test and Bradford protein assay shows that this phosphorus-free anolyte effectively inhibits the growth and reproduction of microorganisms suspended in the solution and greatly reduces the suspended cell mass. As a result, it considerably enhances the coulombic efficiency (CE) of MFCs. When the acetate concentration is 11 mM, the CE of the MFC using the pH 7 phosphate-containing anolyte is 9.7% and the CE with the pH 8.3 phosphate-containing anolyte is 9.1%, while the CE of the MFC using the phosphorus-free anolyte (pH 8.3) achieves 26.6%. This study demonstrates that this phosphorus-free anolyte holds the potential to enhance the feasibility for practical applications of MFCs.

  20. Efficiency of SOFC type fuel cells; Eficiencia de celulas combustiveis do tipo SOFC

    Energy Technology Data Exchange (ETDEWEB)

    Amaral, Alexandre Alves do; Matos, Francisco F.; Boaventura, Jaime S.; Benedicto, Joao Paulo S.; Alencar, Marcelo [Universidade Federal da Bahia (UFBA), Salvador, BA (Brazil). Inst. de Quimica. Dept. de Fisico-Quimica

    2006-07-01

    production of electric energy, mainly due to the fact that it is virtually no pollutant. Typically, the SOFC is constituted of at least seven distinct phases: fuel, anode, electrolyte substrate (separating the two electrodes), cathode, air, and electrical inter connectors (completing the electrical circuit). Thermodynamics clearly shows that electrochemical systems only can be reversible when homogeneous, what it is not case of the Sofc. Therefore, the application of equilibrium thermodynamics to these systems is incorrect. This work proposes that the Sofc can be better depicted from reactions between adsorbed species. The efficiency then is calculated as the ratio between the free energy of these reactions to the combustion heat. Thermodynamic parameter estimative is developed for the global and adsorbed species reactions. (author)

  1. TECHNOLOGY FOR EFFICIENT USAGE OF HYDROCARBON-CONTAINING WASTE IN PRODUCTION OF MULTI-COMPONENT SOLID FUEL

    Directory of Open Access Journals (Sweden)

    B. M. Khroustalev

    2016-01-01

    Full Text Available The paper considers modern approaches to usage of hydrocarbon-containing waste as energy resources and presents description of investigations, statistic materials, analysis results on formation of hydrocarbon-containing waste in the Republic of Belarus. Main problems pertaining to usage of waste as a fuel and technologies for their application have been given in the paper. The paper describes main results of the investigations and a method for efficient application of viscous hydrocarbon-containing waste as an energy-packed component and a binding material while producing a solid fuel. A technological scheme, a prototype industrial unit which are necessary to realize a method for obtaining multi-component solid fuel are represented in the paper. A paper also provides a model of technological process with efficient sequence of technological operations and parameters of optimum component composition. Main factors exerting significant structure-formation influence in creation of structural composition of multi-component solid fuel have been presented in the paper. The paper gives a graphical representation of the principle for selection of mixture particles of various coarseness to form a solid fuel while using a briquetting method and comprising viscous hydrocarbon-containing waste. A dependence of dimensionless concentration g of emissions into atmosphere during burning of two-component solid fuel has been described in the paper. The paper analyzes an influence of the developed methodology for emission calculation of multi-component solid fuels and reveals a possibility to optimize the component composition in accordance with ecological function and individual peculiar features of fuel-burning equipment. Special features concerning storage and transportation, advantages and disadvantages, comparative characteristics, practical applicability of the developed multi-component solid fuel have been considered and presented in the paper. The paper

  2. Electric Vehicles - Promoting Fuel Efficiency and Renewable Energy in Danish Transport

    DEFF Research Database (Denmark)

    Jørgensen, Kaj

    1997-01-01

    Analysis of electric vehicles as energy carrier for renewable energy and fossil fuels, including comparisons with other energy carriers (hydrogen, bio-fuels)......Analysis of electric vehicles as energy carrier for renewable energy and fossil fuels, including comparisons with other energy carriers (hydrogen, bio-fuels)...

  3. Active Duty C-17 Aircraft Commander Fuel Efficiency Metrics and Goal Evaluation

    Science.gov (United States)

    2015-03-26

    options. Finally, Nicholson’s (2009:1-61) work was primarily focused on cost-effectiveness of replacing petroleum-based fuel with biodiesel . Fuel...Gillson, A. “Flight Fuel Planning Policy Letter,” HQ AMC/A3V, 2014. Hileman, J.I., R.W. Stratton. “Alternative jet fuel feasibility,” Transport Policy

  4. Two-step membrane binding by the bacterial SRP receptor enable efficient and accurate Co-translational protein targeting.

    Science.gov (United States)

    Hwang Fu, Yu-Hsien; Huang, William Y C; Shen, Kuang; Groves, Jay T; Miller, Thomas; Shan, Shu-Ou

    2017-07-28

    The signal recognition particle (SRP) delivers ~30% of the proteome to the eukaryotic endoplasmic reticulum, or the bacterial plasma membrane. The precise mechanism by which the bacterial SRP receptor, FtsY, interacts with and is regulated at the target membrane remain unclear. Here, quantitative analysis of FtsY-lipid interactions at single-molecule resolution revealed a two-step mechanism in which FtsY initially contacts membrane via a Dynamic mode, followed by an SRP-induced conformational transition to a Stable mode that activates FtsY for downstream steps. Importantly, mutational analyses revealed extensive auto-inhibitory mechanisms that prevent free FtsY from engaging membrane in the Stable mode; an engineered FtsY pre-organized into the Stable mode led to indiscriminate targeting in vitro and disrupted FtsY function in vivo. Our results show that the two-step lipid-binding mechanism uncouples the membrane association of FtsY from its conformational activation, thus optimizing the balance between the efficiency and fidelity of co-translational protein targeting.

  5. A low-frequency wave motion mechanism enables efficient energy transport in carbon nanotubes at high heat fluxes.

    Science.gov (United States)

    Zhang, Xiaoliang; Hu, Ming; Poulikakos, Dimos

    2012-07-11

    The great majority of investigations of thermal transport in carbon nanotubes (CNTs) in the open literature focus on low heat fluxes, that is, in the regime of validity of the Fourier heat conduction law. In this paper, by performing nonequilibrium molecular dynamics simulations we investigated thermal transport in a single-walled CNT bridging two Si slabs under constant high heat flux. An anomalous wave-like kinetic energy profile was observed, and a previously unexplored, wave-dominated energy transport mechanism is identified for high heat fluxes in CNTs, originated from excited low frequency transverse acoustic waves. The transported energy, in terms of a one-dimensional low frequency mechanical wave, is quantified as a function of the total heat flux applied and is compared to the energy transported by traditional Fourier heat conduction. The results show that the low frequency wave actually overtakes traditional Fourier heat conduction and efficiently transports the energy at high heat flux. Our findings reveal an important new mechanism for high heat flux energy transport in low-dimensional nanostructures, such as one-dimensional (1-D) nanotubes and nanowires, which could be very relevant to high heat flux dissipation such as in micro/nanoelectronics applications.

  6. Fine-Tuning the Quasi-3D Geometry: Enabling Efficient Nonfullerene Organic Solar Cells Based on Perylene Diimides.

    Science.gov (United States)

    Liu, Zhitian; Zhang, Linhua; Shao, Ming; Wu, Yao; Zeng, Di; Cai, Xiang; Duan, Jiashun; Zhang, Xiaolu; Gao, Xiang

    2018-01-10

    The geometries of acceptors based on perylene diimides (PDIs) are important for improving the phase separation and charge transport in organic solar cells. To fine-tune the geometry, biphenyl, spiro-bifluorene, and benzene were used as the core moiety to construct quasi-three-dimensional nonfullerene acceptors based on PDI building blocks. The molecular geometries, energy levels, optical properties, photovoltaic properties, and exciton kinetics were systematically studied. The structure-performance relationship was discussed as well. Owing to the finest phase separation, the highest charge mobility and smallest nongeminate recombination, the power conversion efficiency of nonfullerene solar cells using PDI derivatives with biphenyl core (BP-PDI 4 ) as acceptor reached 7.3% when high-performance wide band gap donor material poly[(2,6-(4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)-benzo[1,2-b:4,5-b']dithiophene))-alt-(5,5-(1',3'-di-2-thienyl-5',7'-bis(2-ethylhexyl)benzo[1',2'-c:4',5'-c']dithiophene-4,8-dione))] was blended.

  7. Lipoprotein-biomimetic nanostructure enables efficient targeting delivery of siRNA to Ras-activated glioblastoma cells via macropinocytosis

    Science.gov (United States)

    Huang, Jia-Lin; Jiang, Gan; Song, Qing-Xiang; Gu, Xiao; Hu, Meng; Wang, Xiao-Lin; Song, Hua-Hua; Chen, Le-Pei; Lin, Ying-Ying; Jiang, Di; Chen, Jun; Feng, Jun-Feng; Qiu, Yong-Ming; Jiang, Ji-Yao; Jiang, Xin-Guo; Chen, Hong-Zhuan; Gao, Xiao-Ling

    2017-05-01

    Hyperactivated Ras regulates many oncogenic pathways in several malignant human cancers including glioblastoma and it is an attractive target for cancer therapies. Ras activation in cancer cells drives protein internalization via macropinocytosis as a key nutrient-gaining process. By utilizing this unique endocytosis pathway, here we create a biologically inspired nanostructure that can induce cancer cells to `drink drugs' for targeting activating transcription factor-5 (ATF5), an overexpressed anti-apoptotic transcription factor in glioblastoma. Apolipoprotein E3-reconstituted high-density lipoprotein is used to encapsulate the siRNA-loaded calcium phosphate core and facilitate it to penetrate the blood-brain barrier, thus targeting the glioblastoma cells in a macropinocytosis-dependent manner. The nanostructure carrying ATF5 siRNA exerts remarkable RNA-interfering efficiency, increases glioblastoma cell apoptosis and inhibits tumour cell growth both in vitro and in xenograft tumour models. This strategy of targeting the macropinocytosis caused by Ras activation provides a nanoparticle-based approach for precision therapy in glioblastoma and other Ras-activated cancers.

  8. A Fast Silver Staining Protocol Enabling Simple and Efficient Detection of SSR Markers using a Non-denaturing Polyacrylamide Gel.

    Science.gov (United States)

    Huang, Ling; Deng, Xiaohui; Li, Ronghua; Xia, Yanshi; Bai, Guihua; Siddique, Kadambot H M; Guo, Peiguo

    2018-04-20

    Simple Sequence Repeat (SSR) is one of the most effective markers used in plant and animal genetic research and molecular breeding programs. Silver staining is a widely used method for the detection of SSR markers in a polyacrylamide gel. However, conventional protocols for silver staining are technically demanding and time-consuming. Like many other biological laboratory techniques, silver staining protocols have been steadily optimized to improve detection efficiency. Here, we report a simplified silver staining method that significantly reduces reagent costs and enhances the detection resolution and picture clarity. The new method requires two major steps (impregnation and development) and three reagents (silver nitrate, sodium hydroxide, and formaldehyde), and only 7 min of processing for a non-denaturing polyacrylamide gel. Compared to previously reported protocols, this new method is easier, quicker and uses fewer chemical reagents for SSR detection. Therefore, this simple, low-cost, and effective silver staining protocol will benefit genetic mapping and marker-assisted breeding by a quick generation of SSR marker data.

  9. High-Efficiency Fullerene Solar Cells Enabled by a Spontaneously Formed Mesostructured CuSCN-Nanowire Heterointerface

    KAUST Repository

    Sit, Wai-Yu

    2018-02-02

    Fullerenes and their derivatives are widely used as electron acceptors in bulk-heterojunction organic solar cells as they combine high electron mobility with good solubility and miscibility with relevant semiconducting polymers. However, studies on the use of fullerenes as the sole photogeneration and charge-carrier material are scarce. Here, a new type of solution-processed small-molecule solar cell based on the two most commonly used methanofullerenes, namely [6,6]-phenyl-C61-butyric acid methyl ester (PC60BM) and [6,6]-phenyl-C71-butyric acid methyl ester (PC70BM), as the light absorbing materials, is reported. First, it is shown that both fullerene derivatives exhibit excellent ambipolar charge transport with balanced hole and electron mobilities. When the two derivatives are spin-coated over the wide bandgap p-type semiconductor copper (I) thiocyanate (CuSCN), cells with power conversion efficiency (PCE) of ≈1%, are obtained. Blending the CuSCN with PC70BM is shown to increase the performance further yielding cells with an open-circuit voltage of ≈0.93 V and a PCE of 5.4%. Microstructural analysis reveals that the key to this success is the spontaneous formation of a unique mesostructured p–n-like heterointerface between CuSCN and PC70BM. The findings pave the way to an exciting new class of single photoactive material based solar cells.

  10. Influence of diffusion of fuel-efficient motor vehicles on gasoline demand for individual user owned passenger cars

    International Nuclear Information System (INIS)

    Sakaguchi, Takahiro

    2000-01-01

    Trends in the demand for petrol in Japan for cars owned by individuals are discussed with reference to expected improvements in fuel efficiency for new models and the results of a survey of user preferences for fuel-efficient vehicles. Demand for petrol in Japan has continued to increase in line with the number of cars used by individual owners. A questionnaire on motor vehicles sent to households found that, while cost and body style were the primary factors in car purchase, three-quarters of respondents would consider buying a low fuel consumption (LFC) version of the model chosen. The influence of LFC vehicles on future demand for petrol was estimated for up to 2015 by combining market timing with consumer preferences. Comparison of the estimated petrol consumption by LFC cars with the Government's requirement for reduced energy use by the transport sector in order to meet its climate change targets indicated a shortfall and a need to increase consumer demand for LFC vehicles. Government measures to reduce energy use in the transport sector, fuel efficiency targets for 2010, major LFC cars, fuel efficiency improvements by major Japanese motor manufacturers and scenarios for assessing the influence of LFC cars are summarised in five tables. Trends in petrol consumption and estimated use by individual user owned passenger cars are shown graphically

  11. Powering a Home with Just 25 Watts of Solar PV. Super-Efficient Appliances Can Enable Expanded Off-Grid Energy Service Using Small Solar Power Systems

    Energy Technology Data Exchange (ETDEWEB)

    Phadke, Amol A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Jacobson, Arne [Schatz Energy Research Center, Arcata, CA (United States); Park, Won Young [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lee, Ga Rick [Schatz Energy Research Center, Arcata, CA (United States); Alstone, Peter [Univ. of California, Berkeley, CA (United States); Khare, Amit [Schatz Energy Research Center, Arcata, CA (United States)

    2015-04-01

    Highly efficient direct current (DC) appliances have the potential to dramatically increase the affordability of off-grid solar power systems used for rural electrification in developing countries by reducing the size of the systems required. For example, the combined power requirement of a highly efficient color TV, four DC light emitting diode (LED) lamps, a mobile phone charger, and a radio is approximately 18 watts and can be supported by a small solar power system (at 27 watts peak, Wp). Price declines and efficiency advances in LED technology are already enabling rapidly increased use of small off-grid lighting systems in Africa and Asia. Similar progress is also possible for larger household-scale solar home systems that power appliances such as lights, TVs, fans, radios, and mobile phones. When super-efficient appliances are used, the total cost of solar home systems and their associated appliances can be reduced by as much as 50%. The results vary according to the appliances used with the system. These findings have critical relevance for efforts to provide modern energy services to the 1.2 billion people worldwide without access to the electrical grid and one billion more with unreliable access. However, policy and market support are needed to realize rapid adoption of super-efficient appliances.

  12. Local flow management/profile descent algorithm. Fuel-efficient, time-controlled profiles for the NASA TSRV airplane

    Science.gov (United States)

    Groce, J. L.; Izumi, K. H.; Markham, C. H.; Schwab, R. W.; Thompson, J. L.

    1986-01-01

    The Local Flow Management/Profile Descent (LFM/PD) algorithm designed for the NASA Transport System Research Vehicle program is described. The algorithm provides fuel-efficient altitude and airspeed profiles consistent with ATC restrictions in a time-based metering environment over a fixed ground track. The model design constraints include accommodation of both published profile descent procedures and unpublished profile descents, incorporation of fuel efficiency as a flight profile criterion, operation within the performance capabilities of the Boeing 737-100 airplane with JT8D-7 engines, and conformity to standard air traffic navigation and control procedures. Holding and path stretching capabilities are included for long delay situations.

  13. Energy efficiency improvement and fuel savings in water heaters using baffles

    International Nuclear Information System (INIS)

    Moeini Sedeh, Mahmoud; Khodadadi, J.M.

    2013-01-01

    Highlights: ► Thermal efficiency improved by simple/novel design of baffles inside water reservoir. ► Noticeable steady-state natural gas savings of about 5%. ► Extensive 3-D numerical investigations followed by experimental verifications. ► Baffle designs prototyped in identical water heaters for ANSI/US DOE test protocols. ► Numerical/experimental results verified thermal efficiency improvement and fuel savings. -- Abstract: Thermal efficiency improvement of a water heater was investigated numerically and experimentally in response to presence of a baffle, particularly designed for modifying the flow field within the water reservoir and enhancing heat transfer extracted into the water tank. A residential natural gas-fired water heater was selected for modifying its water tank through introducing a baffle for lowering natural gas consumption by 5% as a target. Based on the geometric features of the selected water heater, three-dimensional models of the water heater subsections were developed. Upon detailed studies of flow and heat transfer in each subsection, various sub-models were integrated to a complete model of the water heater. Thermal performance of the selected water heater was investigated numerically using computational fluid dynamics analysis. Prior to baffle design process and in order to verify the developed model of the water heater, time-dependent numerically-predicted temperatures were compared to the experimentally-measured temperatures under the same conditions at six (6) different locations inside the water tank and good agreement was observed. Upon verifying the numerical model, the fluid flow and heat transfer patterns were characterized for the selected water heater. The overall design of the baffle and its location and orientation were finalized based on the numerical results and a set of parametric studies. Finally, two baffle designs were proposed, with the second design being an optimized version of the first design. The

  14. Highly efficient conversion of terpenoid biomass to jet-fuel range cycloalkanes in a biphasic tandem catalytic process

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Xiaokun [Univ. of Nevada, Reno, NV (United States); Li, Teng [Washington State Univ., Pullman, WA (United States); Tang, Kan [Washington State Univ., Pullman, WA (United States); Zhou, Xinpei [Univ. of Nevada, Reno, NV (United States); Lu, Mi [Univ. of Nevada, Reno, NV (United States); Ounkham, Whalmany L. [Univ. of Nevada, Reno, NV (United States); Spain, Stephen M. [Univ. of Nevada, Reno, NV (United States); Frost, Brian J. [Univ. of Nevada, Reno, NV (United States); Lin, Hongfei [Washington State Univ., Pullman, WA (United States)

    2017-06-12

    The demand for bio-jet fuels to reduce carbon emissions is increasing substantially in the aviation sector, while the scarcity of high-density jet fuel components limits the use of bio-jet fuels in high-performance aircrafts compared with conventional jet fuels. In this paper, we report a novel biphasic tandem catalytic process (biTCP) for synthesizing cycloalkanes from renewable terpenoid biomass, such as 1,8-cineole. Multistep tandem reactions, including C–O ring opening by hydrolysis, dehydration, and hydrogenation, were carried out in the “one-pot” biTCP. 1,8-Cineole was efficiently converted to p-menthane at high yields (>99%) in the biTCP under mild reaction conditions. Finally, the catalytic reaction mechanism is discussed.

  15. New, efficient and viable system for ethanol fuel utilization on combined electric/internal combustion engine vehicles

    Science.gov (United States)

    Sato, André G.; Silva, Gabriel C. D.; Paganin, Valdecir A.; Biancolli, Ana L. G.; Ticianelli, Edson A.

    2015-10-01

    Although ethanol can be directly employed as fuel on polymer-electrolyte fuel cells (PEMFC), its low oxidation kinetics in the anode and the crossover to the cathode lead to a substantial reduction of energy conversion efficiency. However, when fuel cell driven vehicles are considered, the system may include an on board steam reformer for converting ethanol into hydrogen, but the hydrogen produced contains carbon monoxide, which limits applications in PEMFCs. Here, we present a system consisting of an ethanol dehydrogenation catalytic reactor for producing hydrogen, which is supplied to a PEMFC to generate electricity for electric motors. A liquid by-product effluent from the reactor can be used as fuel for an integrated internal combustion engine, or catalytically recycled to extract more hydrogen molecules. Power densities comparable to those of a PEMFC operating with pure hydrogen are attained by using the hydrogen rich stream produced by the ethanol dehydrogenation reactor.

  16. CONOCOPHILLIPS FUEL EFFICIENT HIGH-PERFORMANCE(FEHP) SAE 75W90 REAR AXLE GEAR LUBRICANT

    Science.gov (United States)

    This report is on the Environmental Verification Test of a ConocoPhillips real axle gear lubricant to determine whether it could save vehicle fuel. It determined that a verifyable fuel savings could be measured.

  17. Initial Screening of Thermochemical Water-Splitting Cycles for High Efficiency Generation of Hydrogen Fuels Using Nuclear Power

    International Nuclear Information System (INIS)

    Brown, L.C.; Funk, J.F.; Showalter, S.K.

    1999-01-01

    OAK B188 Initial Screening of Thermochemical Water-Splitting Cycles for High Efficiency Generation of Hydrogen Fuels Using Nuclear Power There is currently no large scale, cost-effective, environmentally attractive hydrogen production process, nor is such a process available for commercialization. Hydrogen is a promising energy carrier, which potentially could replace the fossil fuels used in the transportation sector of our economy. Fossil fuels are polluting and carbon dioxide emissions from their combustion are thought to be responsible for global warming. The purpose of this work is to determine the potential for efficient, cost-effective, large-scale production of hydrogen utilizing high temperature heat from an advanced nuclear power station. Almost 800 literature references were located which pertain to thermochemical production of hydrogen from water and over 100 thermochemical watersplitting cycles were examined. Using defined criteria and quantifiable metrics, 25 cycles have been selected for more detailed study

  18. The new Nissan high efficient 1.2L 3cyl GDI supercharged engine enables 95g/km CO2 emissions and high driving performance

    Energy Technology Data Exchange (ETDEWEB)

    Kishi, Kazuaki; Satou, Takeshi [Nissan Motor Co., Ltd., Kanagawa (Japan)

    2012-11-01

    This paper describes a new 1.2-liter three cylinder gasoline engine named HR12DDR, with the target to achieve the lowest level CO2 in the European B-segment market and also, to satisfy the customer's driving pleasure through high output performance. This engine is developed with the consideration of meeting further strict regulations in the years ahead and of the possibility of being an alternative powertrain of diesel in the future as well. As a first step this engine was applied on the European Nissan Micra in 2011; achieving 95g/km CO2 emissions(NEDC mode). This low fuel consumption was realized mainly through technologies which scope to maximize thermal efficiency with high compression ratio, and to minimize the mechanical friction loss. The combustion was optimized by Direct Injection (DI) system. To obtain a better fuel economy performance without sacrificing high output, we chose the supercharger system with bypass valve and magnetic clutch. Details of the HR12DDR are presented here along with highlights of the applied technologies. (orig.)

  19. 76 FR 65971 - Greenhouse Gas Emissions Standards and Fuel Efficiency Standards for Medium- and Heavy-Duty...

    Science.gov (United States)

    2011-10-25

    ... DEPARTMENT OF TRANSPORTATION National Highway Traffic Safety Administration 49 CFR Parts 523 and 535 [NHTSA 2010-0079; EPA-HQ-OAR-2010-0162; FRL-9455-1] RIN 2127-AK74 Greenhouse Gas Emissions... fuel efficiency and reduce greenhouse gas emissions for on-road heavy-duty vehicles, responding to the...

  20. Amorphizing of Cu Nanoparticles toward Highly Efficient and Robust Electrocatalyst for CO2 Reduction to Liquid Fuels with High Faradaic Efficiencies.

    Science.gov (United States)

    Duan, Yan-Xin; Meng, Fan-Lu; Liu, Kai-Hua; Yi, Sha-Sha; Li, Si-Jia; Yan, Jun-Min; Jiang, Qing

    2018-04-01

    Conversion of carbon dioxide (CO 2 ) into valuable chemicals, especially liquid fuels, through electrochemical reduction driven by sustainable energy sources, is a promising way to get rid of dependence on fossil fuels, wherein developing of highly efficient catalyst is still of paramount importance. In this study, as a proof-of-concept experiment, first a facile while very effective protocol is proposed to synthesize amorphous Cu NPs. Unexpectedly, superior electrochemical performances, including high catalytic activity and selectivity of CO 2 reduction to liquid fuels are achieved, that is, a total Faradaic efficiency of liquid fuels can sum up to the maximum value of 59% at -1.4 V, with formic acid (HCOOH) and ethanol (C 2 H 6 O) account for 37% and 22%, respectively, as well as a desirable long-term stability even up to 12 h. More importantly, this work opens a new avenue for improved electroreduction of CO 2 based on amorphous metal catalysts. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Towards an efficient conversion of ethanol in low temperature fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Rao, Vineet [Technische Universitaet Muenchen, Physik Department E19, James-Franck-Str. 1, D-85747 Garching (Germany); Stimming, Ulrich [Technische Universitaet Muenchen, Physik Department E19, James-Franck-Str. 1, D-85747 Garching (Germany); ZAE Bayern, Abteilung 1, Walther-Meissner-Str. 6, D-85748 Garching (Germany)

    2009-07-01

    Direct conversion of ethanol in low temperature fuel cells is a major goal in the development of fuel cells. Advantages of ethanol are its availability from biomass and the high energy density of such liquid fuel. Nevertheless, a major drawback is the incomplete oxidation of ethanol. Recent research focused mainly on novel catalyst materials for the ethanol oxidation reaction (EOR) based on e.g. Pt-Sn. Furthermore, some groups have carried out tests on solid OH- ion exchange membrane fuel cells. Better kinetics of fuel cell processes in such exchange membrane fuel cells could allow using also higher alcohols as fuel. Ethanol has slower kinetics of oxidation in acidic media and several by-products are formed because of incomplete oxidation. In our studies we investigated EOR in alkaline membrane electrode assemblies (MEA). Here, ethanol undergoes significantly more complete electro-oxidation to CO{sub 2} than in case of acidic MEA with same Pt anode.

  2. Modifying woody plants for efficient conversion to liquid and gaseous fuels

    Energy Technology Data Exchange (ETDEWEB)

    Dinus, R.J.; Dimmel, D.R.; Feirer, R.P.; Johnson, M.A.; Malcolm, E.W. (Institute of Paper Science and Technology, Atlanta, GA (USA))

    1990-07-01

    The Short Rotation Woody Crop Program (SRWCP), Department of Energy, is developing woody plant species as sources of renewable energy. Much progress has been made in identifying useful species, and testing site adaptability, stand densities, coppicing abilities, rotation lengths, and harvesting systems. Conventional plant breeding and intensive cultural practices have been used to increase above-ground biomass yields. Given these and foreseeable accomplishments, program leaders are now shifting attention to prospects for altering biomass physical and chemical characteristics, and to ways for improving the efficiency with which biomass can be converted to gaseous and liquid fuels. This report provides a review and synthesis of literature concerning the quantity and quality of such characteristics and constituents, and opportunities for manipulating them via conventional selection and breeding and/or molecular biology. Species now used by SRWCP are emphasized, with supporting information drawn from others as needed. Little information was found on silver maple (Acer saccharinum), but general comparisons (Isenberg 1981) suggest composition and behavior similar to those of the other species. Where possible, conclusions concerning means for and feasibility of manipulation are given, along with expected impacts on conversion efficiency. Information is also provided on relationships to other traits, genotype X environment interactions, and potential trade-offs or limitations. Biomass productivity per se is not addressed, except in terms of effects that may by caused by changes in constituent quality and/or quantity. Such effects are noted to the extent they are known or can be estimated. Likely impacts of changes, however effected, on suitability or other uses, e.g., pulp and paper manufacture, are notes. 311 refs., 4 figs., 9 tabs.

  3. Efficient production and economics of the clean fuel hydrogen. Paper no. IGEC-1-Keynote-Elnashaie

    International Nuclear Information System (INIS)

    Elnashaie, S.

    2005-01-01

    This paper/plenary lecture to this green energy conference briefly discusses six main issues: 1) The future of hydrogen economy; 2) Thermo-chemistry of hydrogen production for different techniques of autothermic operation using different feedstocks; 3) Improvement of the hydrogen yield and minimization of reformer size through combining fast fluidization with hydrogen and oxygen membranes together with CO 2 sequestration; 4) Efficient production of hydrogen using novel Autothermal Circulating Fluidized Bed Membrane Reformer (ACFBMR); 5) Economics of hydrogen production; and, 6) Novel gasification process for hydrogen production from biomass. It is shown that hydrogen economy is not a Myth as some people advocate, and that with well-directed research it will represent a bright future for humanity utilizing such a clean, everlasting fuel, which is also free of deadly conflicts for the control of energy sources. It is shown that autothermic production of hydrogen using novel reformers configurations and wide range of feedstocks is a very promising route towards achieving a successful hydrogen economy. A novel process for the production of hydrogen from different renewable biomass sources is presented and discussed. The process combines the principles of pyrolysis with the simultaneous use of catalyst, membranes and CO 2 sequestration to produce pure hydrogen directly from the unit. Some of the novel processes presented are essential components of modern bio-refineries. (author)

  4. High-fidelity simulations for clean and efficient combustion of alternative fuels

    Energy Technology Data Exchange (ETDEWEB)

    Oefelein, J C; Chen, J H [Reacting Flow Research Department, Sandia National Laboratories, Livermore, CA 94550 (United States); Sankaran, R, E-mail: oefelei@sandia.go [National Center for Computational Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States)

    2009-07-01

    There is an urgent and growing demand for high-fidelity simulations that capture complex turbulence-chemistry interactions in propulsion and power systems, and in particular, that capture and discriminate the effects of fuel variability. This project addresses this demand using the Large Eddy Simulation (LES) technique (led by Oefelein) and the Direct Numerical Simulation (DNS) technique (led by Chen). In particular, we are conducting research under the INCITE program that is tightly coupled with funded projects established under the DOE Basic Energy Sciences and Energy Efficiency and Renewable Energy programs that will provide the foundational science required to develop a predictive modeling capability for design of advanced engines for transportation. Application of LES provides the formal ability to treat the full range of multidimensional time and length scales that exist in turbulent reacting flows in a computationally feasible manner and thus provides a way to simulate reacting flow phenomena in complex internal-combustion engine geometries at device relevant conditions. Application of DNS provides a way to study fundamental issues related to small-scale combustion processes in canonical configurations to understand dynamics that occur over a range of reactive-diffusive scales. Here we describe the challenges and present representative examples of the types of simulations each respective tool has been used for as part of the INCITE program. We focus on recent experiences on the Oak Ridge National Laboratory (ORNL) National Center for Computational Sciences (NCCS) Cray-XT Platform (i.e., Jaguar).

  5. Automatic control of load increases power and efficiency in a microbial fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Premier, Giuliano C.; Kim, Jung Rae; Michie, Iain [Sustainable Environment Research Centre (SERC), Faculty of Advanced Technology, University of Glamorgan, Pontypridd, Mid-Glamorgan CF37 1DL (United Kingdom); Dinsdale, Richard M.; Guwy, Alan J. [Sustainable Environment Research Centre (SERC), Faculty of Health, Sport and Science, University of Glamorgan, Pontypridd, Mid-Glamorgan CF37 1DL (United Kingdom)

    2011-02-15

    Increasing power production and coulombic efficiency (CE) of microbial fuel cells (MFCs) is a common research ambition as the viability of the technology depends to some extent on these measures of performance. As MFCs are typically time varying systems, comparative studies of controlled and un-controlled external load impedance are needed to show if control affects the biocatalyst development and hence MFC performance. The application of logic based control of external load resistance is shown to increase the power generated by the MFC, when compared to an equivalent system which has a static resistive load. The controlled MFC generated 1600 {+-} 400 C, compared to 300 {+-} 10 C with an otherwise replicate fixed load MFC system. The use of a parsimonious gradient based control was able to increase the CE to within the range of 15.1-22.7%, while the CE for a 200 {omega} statically loaded MFC lay in the range 3.3-3.7%. The controlled MFC improves the electrogenic anodic biofilm selection for power production, indicating that greater power and substrate conversion can be achieved by controlling load impedance. Load control ensured sustainable current demand, applied microbial selection pressures and provided near-optimal impedance for power transference, compared to the un-controlled system. (author)

  6. Potential pyrolysis pathway assessment for microalgae-based aviation fuel based on energy conversion efficiency and life cycle

    International Nuclear Information System (INIS)

    Guo, Fang; Wang, Xin; Yang, Xiaoyi

    2017-01-01

    Highlights: • High lipid content in microalgae increases energy conversion efficiency. • Indirect pathway has the highest mass ratio, energy ratio and energy efficiency. • The Isochrysis indirect pathway produces most kerosene component precursor. • The Isochrysis indirect pyrolysis pathway shows the best performance in LCA. - Abstract: Although the research of microalgae pyrolysis has been conducted for many years, there is a lack of investigations on energy efficiency and life cycle assessment. In this study, we investigated the biocrude yield and energy efficiency of direct pyrolysis, microalgae residue pyrolysis after lipid extraction (indirect pyrolysis), and different microalgae co-pyrolysis. This research also investigated the life cycle assessment of the three different pyrolysis pathways. A system boundary of Well-to-Wake (WTWa) was defined and included sub-process models, such as feedstock production, fuel production and pump-to-wheels (PTW) stages. The pathway of Isochrysis indirect pyrolysis shows the best performance in the mass ratio and energy ratio, produces the most kerosene component precursor, has the lowest WTWa total energy input, fossil fuel consumption and greenhouse gas emissions, and resultes in the best energy efficiency. All the evidence indicates that Isochrysis R2 pathway is a potential and optimal pyrolysis pathway to liquid biofuels. The mass ratio of pyrolysis biocrude is shown to be the decisive factor for different microalgae species. The sensitivity analysis results also indicates that the life cycle indicators are particularly sensitive to the mass ratio of pyrolysis biocrude for microalgae-based hydrotreated pyrolysis aviation fuel.

  7. Effects of operating conditions and fuel properties on emission performance and combustion efficiency of a swirling fluidized-bed combustor fired with a biomass fuel

    International Nuclear Information System (INIS)

    Kuprianov, Vladimir I.; Kaewklum, Rachadaporn; Chakritthakul, Songpol

    2011-01-01

    This work reports an experimental study on firing 80 kg/h rice husk in a swirling fluidized-bed combustor (SFBC) using an annular air distributor as the swirl generator. Two NO x emission control techniques were investigated in this work: (1) air staging of the combustion process, and (2) firing rice husk as moisturized fuel. In the first test series for the air-staged combustion, CO, NO and C x H y emissions and combustion efficiency were determined for burning 'as-received' rice husk at fixed excess air of 40%, while secondary-to-primary air ratio (SA/PA) was ranged from 0.26 to 0.75. The effects of SA/PA on CO and NO emissions from the combustor were found to be quite weak, whereas C x H y emissions exhibited an apparent influence of air staging. In the second test series, rice husks with the fuel-moisture content of 8.4% to 35% were fired at excess air varied from 20% to 80%, while the flow rate of secondary air was fixed. Radial and axial temperature and gas concentration (O 2 , CO, NO) profiles in the reactor, as well as CO and NO emissions, are discussed for the selected operating conditions. The temperature and gas concentration profiles for variable fuel quality exhibited significant effects of both fuel-moisture and excess air. As revealed by experimental results, the emission of NO from this SFBC can be substantially reduced through moisturizing rice husk, while CO is effectively mitigated by injection of secondary air into the bed splash zone, resulting in a rather low emission of CO and high (over 99%) combustion efficiency of the combustor for the ranges of operating conditions and fuel properties.

  8. Efficiency Analysis of Technological Methods for Reduction of NOx Emissions while Burning Hydrocarbon Fuels in Heat and Power Plants

    Directory of Open Access Journals (Sweden)

    S. M. Kabishov

    2013-01-01

    Full Text Available The paper contains a comparative efficiency analysis pertaining to application of existing technological methods for suppression of nitric oxide formation in heating boilers of heat generators. A special attention has been given to investigation of NOx  emission reduction while burning hydrocarbon fuel with the help of oxygen-enriched air. The calculations have demonstrated that while enriching oxidizer with the help of oxygen up to 50 % (by volume it is possible to reduce volume of NOx formation (while burning fuel unit by 21 %.

  9. Low-cost high-efficiency GDCI engines for low octane fuels

    Energy Technology Data Exchange (ETDEWEB)

    Kolodziej, Christopher P.; Sellnau, Mark C.

    2018-01-09

    A GDCI engine has a piston arranged within a cylinder to provide a combustion chamber. According to one embodiment, the GDCI engine operates using a method that includes the steps of supplying a hydrocarbon fuel to the combustion chamber with a research octane number in the range of about 30-65. The hydrocarbon fuel is injected in completely stratified, multiple fuel injections before a start of combustion and supplying a naturally aspirated air charge to the combustion chamber.

  10. Evaluation of efficiency of axial profiling in WWER-440 fuel assemblies

    International Nuclear Information System (INIS)

    Ananjev, Yu. A.; Kurakin, K. Yu.; Artemov, V.G.; Ivanov, A.S.

    2005-01-01

    The present report deals with consideration of fuel enrichment axial profiling in WWER-440 assemblies. The study is performed on improving the effectiveness of fuel utilization using the example of implementing the axial profiling in the assemblies of the second generation. For simulation of fuel loadings the computer code package SAPFIR 9 5 and RC is used that allows for correct consideration of specific features of assemblies design changes. The methodical approach to assessment of effectiveness of implementing the axial profiling is considered with the use of capabilities of the mentioned code package. In conclusion the recommendations are given on using the fuel enrichment axial profiling in WWER-440 assemblies (Authors)

  11. 5S rRNA Promoter for Guide RNA Expression Enabled Highly Efficient CRISPR/Cas9 Genome Editing in Aspergillus niger.

    Science.gov (United States)

    Zheng, Xiaomei; Zheng, Ping; Zhang, Kun; Cairns, Timothy C; Meyer, Vera; Sun, Jibin; Ma, Yanhe

    2018-04-30

    The CRISPR/Cas9 system is a revolutionary genome editing tool. However, in eukaryotes, search and optimization of a suitable promoter for guide RNA expression is a significant technical challenge. Here we used the industrially important fungus, Aspergillus niger, to demonstrate that the 5S rRNA gene, which is both highly conserved and efficiently expressed in eukaryotes, can be used as a guide RNA promoter. The gene editing system was established with 100% rates of precision gene modifications among dozens of transformants using short (40-bp) homologous donor DNA. This system was also applicable for generation of designer chromosomes, as evidenced by deletion of a 48 kb gene cluster required for biosynthesis of the mycotoxin fumonisin B1. Moreover, this system also facilitated simultaneous mutagenesis of multiple genes in A. niger. We anticipate that the use of the 5S rRNA gene as guide RNA promoter can broadly be applied for engineering highly efficient eukaryotic CRISPR/Cas9 toolkits. Additionally, the system reported here will enable development of designer chromosomes in model and industrially important fungi.

  12. Efficient solar-driven synthesis, carbon capture, and desalinization, STEP: solar thermal electrochemical production of fuels, metals, bleach

    Energy Technology Data Exchange (ETDEWEB)

    Licht, S. [Department of Chemistry, George Washington University, Washington, DC (United States)

    2011-12-15

    STEP (solar thermal electrochemical production) theory is derived and experimentally verified for the electrosynthesis of energetic molecules at solar energy efficiency greater than any photovoltaic conversion efficiency. In STEP the efficient formation of metals, fuels, chlorine, and carbon capture is driven by solar thermal heated endothermic electrolyses of concentrated reactants occuring at a voltage below that of the room temperature energy stored in the products. One example is CO{sub 2}, which is reduced to either fuels or storable carbon at a solar efficiency of over 50% due to a synergy of efficient solar thermal absorption and electrochemical conversion at high temperature and reactant concentration. CO{sub 2}-free production of iron by STEP, from iron ore, occurs via Fe(III) in molten carbonate. Water is efficiently split to hydrogen by molten hydroxide electrolysis, and chlorine, sodium, and magnesium from molten chlorides. A pathway is provided for the STEP decrease of atmospheric carbon dioxide levels to pre-industrial age levels in 10 years. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  13. An Efficient Two-Objective Hybrid Local Search Algorithm for Solving the Fuel Consumption Vehicle Routing Problem

    Directory of Open Access Journals (Sweden)

    Weizhen Rao

    2016-01-01

    Full Text Available The classical model of vehicle routing problem (VRP generally minimizes either the total vehicle travelling distance or the total number of dispatched vehicles. Due to the increased importance of environmental sustainability, one variant of VRPs that minimizes the total vehicle fuel consumption has gained much attention. The resulting fuel consumption VRP (FCVRP becomes increasingly important yet difficult. We present a mixed integer programming model for the FCVRP, and fuel consumption is measured through the degree of road gradient. Complexity analysis of FCVRP is presented through analogy with the capacitated VRP. To tackle the FCVRP’s computational intractability, we propose an efficient two-objective hybrid local search algorithm (TOHLS. TOHLS is based on a hybrid local search algorithm (HLS that is also used to solve FCVRP. Based on the Golden CVRP benchmarks, 60 FCVRP instances are generated and tested. Finally, the computational results show that the proposed TOHLS significantly outperforms the HLS.

  14. From here to efficiency : time lags between the introduction of new technology and the achievement of fuel savings

    International Nuclear Information System (INIS)

    Mintz, M.; Vyas, A.; Wang, M.; Stodolsky, F.; Cuenca, R.; Gaines, L.

    1999-01-01

    In this paper, the energy savings of new technology offering significant improvements in fuel efficiency are tracked for over 20 years as vehicles incorporating that technology enter the fleet and replace conventional light-duty vehicles. Two separate analyses are discussed: a life-cycle analysis of aluminum-intensive vehicles and a fuel-cycle analysis of the energy and greenhouse gas emissions of double vs. triple fuel-economy vehicles. In both efforts, market-penetration modeling is used to simulate the rate at which new technology enters the new fleet, and stock-adjustment modeling is used to capture the inertia in turnover of new and existing current-technology vehicles. Together, these two effects--slowed market penetration and delayed vehicle replacement--increase the time lag between market introduction and the achievement of substantial energy savings. In both cases, 15-20 years elapse, before savings approach these levels

  15. Comparison based on energy and exergy analyses of the potential cogeneration efficiencies for fuel cells and other electricity generation devices

    Energy Technology Data Exchange (ETDEWEB)

    Rosen, M A [Ryerson Polytechnical Inst., Toronto, (CA). Dept. of Mechanical Engineering

    1990-01-01

    Comparisons of the potential cogeneration efficiencies are made, based on energy and exergy analyses, for several devices for electricity generation. The investigation considers several types of fuel cell system (Phosphoric Acid, Alkaline, Solid Polymer Electrolyte, Molten Carbonate and Solid Oxide), and several fossil-fuel and nuclear cogeneration systems based on steam power plants. In the analysis, each system is modelled as a device for which fuel and air enter, and electrical- and thermal-energy products and material and thermal-energy wastes exit. The results for all systems considered indicate that exergy analyses should be used when analysing the cogeneration potential of systems for electricity generation, because they weigh the usefulnesses of heat and electricity on equivalent bases. Energy analyses tend to present overly optimistic views of performance. These findings are particularly significant when large fractions of the heat output from a system are utilized for cogeneration. (author).

  16. Highly Efficient and Visible Light Responsive Heterojunction Composites as Dual Photoelectrodes for Photocatalytic Fuel Cell

    Directory of Open Access Journals (Sweden)

    Honghui Pan

    2018-01-01

    Full Text Available In the present work, a novel photocatalytic fuel cell (PFC system involving a dual heterojunction photoelectrodes, viz. polyaniline/TiO2 nanotubes (PANI/TiO2 NTs photoanode and CuO/Co3O4 nanorods (CuO/Co3O4 NRs photocathode, has been designed. Compared to TiO2 NTs electrode of PFC, the present heterojunction design not only enhances the visible light absorption but also offers the higher efficiency in degrading Rhodamine B–a model organic pollutant. The study includes an evaluation of the dual performance of the photoelectrodes as well. Under visible-light irradiation of 3 mW cm−2, the cell composed of the photoanode PANI/TiO2 NTs and CuO/Co3O4 NRs photocathode forms an interior bias of +0.24 V within the PFC system. This interior bias facilitated the transfer of electrons from the photoanode to photocathode across the external circuit and combined with the holes generated therein along with a simultaneous power production. In this manner, the separation of electron/hole pair was achieved in the photoelectrodes by releasing the holes and electrons of PANI/TiO2 NTs photoanode and CuO/Co3O4 NRs photocathode, respectively. Using this PFC system, the degradation of Rhodamine B in aqueous media was achieved to an extent of 68.5% within a reaction duration of a four-hour period besides a simultaneous power generation of 85 μA cm−2.

  17. A novel pilot-scale stacked microbial fuel cell for efficient electricity generation and wastewater treatment.

    Science.gov (United States)

    Wu, Shijia; Li, Hui; Zhou, Xuechen; Liang, Peng; Zhang, Xiaoyuan; Jiang, Yong; Huang, Xia

    2016-07-01

    A novel stacked microbial fuel cell (MFC) which had a total volume of 72 L with granular activated carbon (GAC) packed bed electrodes was constructed and verified to present remarkable power generation and COD removal performance due to its advantageous design of stack and electrode configuration. During the fed-batch operation period, a power density of 50.9 ± 1.7 W/m(3) and a COD removal efficiency of 97% were achieved within 48 h. Because of the differences among MFC modules in the stack, reversal current occurred in parallel circuit connection with high external resistances (>100 Ω). This reversal current consequently reduced the electrochemical performance of some MFC modules and led to a lower power density in parallel circuit connection than that in independent circuit connection. While increasing the influent COD concentrations from 200 to 800 mg/L at hydraulic retention time of 1.25 h in continuous operation mode, the power density of stacked MFC increased from 25.6 ± 2.5 to 42.1 ± 1.2 W/m(3) and the COD removal rates increased from 1.3 to 5.2 kg COD/(m(3) d). This study demonstrated that this novel MFC stack configuration coupling with GAC packed bed electrode could be a feasible strategy to effectively scale up MFC systems. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Automotive Fuel Processor Development and Demonstration with Fuel Cell Systems

    Energy Technology Data Exchange (ETDEWEB)

    Nuvera Fuel Cells

    2005-04-15

    The potential for fuel cell systems to improve energy efficiency and reduce emissions over conventional power systems has generated significant interest in fuel cell technologies. While fuel cells are being investigated for use in many applications such as stationary power generation and small portable devices, transportation applications present some unique challenges for fuel cell technology. Due to their lower operating temperature and non-brittle materials, most transportation work is focusing on fuel cells using proton exchange membrane (PEM) technology. Since PEM fuel cells are fueled by hydrogen, major obstacles to their widespread use are the lack of an available hydrogen fueling infrastructure and hydrogen's relatively low energy storage density, which leads to a much lower driving range than conventional vehicles. One potential solution to the hydrogen infrastructure and storage density issues is to convert a conventional fuel such as gasoline into hydrogen onboard the vehicle using a fuel processor. Figure 2 shows that gasoline stores roughly 7 times more energy per volume than pressurized hydrogen gas at 700 bar and 4 times more than liquid hydrogen. If integrated properly, the fuel processor/fuel cell system would also be more efficient than traditional engines and would give a fuel economy benefit while hydrogen storage and distribution issues are being investigated. Widespread implementation of fuel processor/fuel cell systems requires improvements in several aspects of the technology, including size, startup time, transient response time, and cost. In addition, the ability to operate on a number of hydrocarbon fuels that are available through the existing infrastructure is a key enabler for commercializing these systems. In this program, Nuvera Fuel Cells collaborated with the Department of Energy (DOE) to develop efficient, low-emission, multi-fuel processors for transportation applications. Nuvera's focus was on (1) developing fuel

  19. Sensitivity study for accident tolerant fuels: Property comparisons and behavior simulations in a simplified PWR to enable ATF development and design

    Energy Technology Data Exchange (ETDEWEB)

    Spencer, Kristina Yancey, E-mail: kristina.yancey@gmail.com; Sudderth, Laura; Brito, Ryan A.; Evans, Jordan A.; Hart, Clifford S.; Hu, Anbang; Jati, Andi; Stern, Karyn; McDeavitt, Sean M., E-mail: mcdeavitt@tamu.edu

    2016-12-01

    Highlights: • This study compared four accident tolerant fuels against uranium dioxide. • Material property correlations were developed to evaluate fuel performance. • The fuels’ neutronic and thermal hydraulic behaviors were studied in the AP1000. • No fuel type performed better in all areas, but each has strengths and weaknesses. • More research is needed to build a complete model of the fuel performances. - Abstract: Since the events at the Fukushima-Daiichi nuclear power plant, there has been increased interest in developing fuels to better withstand accidents for current light water reactors. Four accident tolerant fuel candidates are uranium oxide with beryllium oxide additives, uranium oxide with silicon carbide matrix additives, uranium nitride, and uranium nitride with uranium silicide composite. The first two candidates represent near-term high performance uranium oxide with high thermal conductivity and neutron transparency, and the second two represent mid-term high-density fuels with highly beneficial thermal properties. This study seeks to understand the benefits and drawbacks of each option in place of uranium dioxide. To assess the material properties for each of the fuel types, an extensive literature review was performed for material property data. Correlations were then made to evaluate the properties during reactor operation. Neutronics and thermal hydraulics studies were also completed to determine the impact of the use of each candidate in an AP1000 reactor. In most cases, the candidate fuels performed more desirably than uranium dioxide, but no fuel type performed better in all aspects. Much more research needs to be performed to build a complete model of the fuel performances, primarily experimental data for uranium silicide. Each of the fuels studied has its own benefits and drawbacks, and the comparisons discussed in this report can be used to aid in determining the most appropriate fuel depending on the desired specifications.

  20. Oxygen permeation through Nafion 117 membrane and its impact on efficiency of polymer membrane ethanol fuel cell

    Science.gov (United States)

    Jablonski, Andrzej; Kulesza, Pawel J.; Lewera, Adam

    2011-05-01

    We investigate oxygen permeation through Nafion 117 membrane in a direct ethanol fuel cell and elucidate how it affects the fuel cell efficiency. An obvious symptom of oxygen permeation is the presence of significant amounts of acetaldehyde and acetic acid in the mixture leaving anode when no current was drawn from the fuel cell (i.e. under the open circuit conditions). This parasitic process severely lowers efficiency of the fuel cell because ethanol is found to be directly oxidized on the surface of catalyst by oxygen coming through membrane from cathode in the absence of electric current flowing in the external circuit. Three commonly used carbon-supported anode catalysts are investigated, Pt, Pt/Ru and Pt/Sn. Products of ethanol oxidation are determined qualitatively and quantitatively at open circuit as a function of temperature and pressure, and we aim at determining whether the oxygen permeation or the catalyst's activity limits the parasitic ethanol oxidation. Our results strongly imply the need to develop more selective membranes that would be less oxygen permeable.

  1. Efficiency analyses of the CANDU spent fuel repository using modified disposal canisters for a deep geological disposal system design

    International Nuclear Information System (INIS)

    Lee, J.Y.; Cho, D.K.; Lee, M.S.; Kook, D.H.; Choi, H.J.; Choi, J.W.; Wang, L.M.

    2012-01-01

    Highlights: ► A reference disposal concept for spent nuclear fuels in Korea has been reviewed. ► To enhance the disposal efficiency, alternative disposal concepts were developed. ► Thermal analyses for alternative disposal concepts were performed. ► From the result of the analyses, the disposal efficiency of the concepts was reviewed. ► The most effective concept was suggested. - Abstract: Deep geological disposal concept is considered to be the most preferable for isolating high-level radioactive waste (HLW), including nuclear spent fuels, from the biosphere in a safe manner. The purpose of deep geological disposal of HLW is to isolate radioactive waste and to inhibit its release of for a long time, so that its toxicity does not affect the human beings and the biosphere. One of the most important requirements of HLW repository design for a deep geological disposal system is to keep the buffer temperature below 100 °C in order to maintain the integrity of the engineered barrier system. In this study, a reference disposal concept for spent nuclear fuels in Korea has been reviewed, and based on this concept, efficient alternative concepts that consider modified CANDU spent fuels disposal canister, were developed. To meet the thermal requirement of the disposal system, the spacing of the disposal tunnels and that of the disposal pits for each alternative concept, were drawn following heat transfer analyses. From the result of the thermal analyses, the disposal efficiency of the alternative concepts was reviewed and the most effective concept suggested. The results of these analyses can be used for a deep geological repository design and detailed analyses, based on exact site characteristics data, will reduce the uncertainty of the results.

  2. Study on the Efficient Disintegration of HTGR Fuel Elements by Electrochemical Method

    International Nuclear Information System (INIS)

    Piao Nan; Chen Ji; Xiao Cuiping; We Mingfen; Che Jing

    2014-01-01

    The spent fuel elements in High- temperature gas-cooled reactor (HTGR) have a special structure, so the head-end process of the spent fuel reprocessing is different from the process of water reactor spent fuel. The first step of head-end process of the HTGR spent fuel reprocessing process is disintegration of the graphite matrix and separation of the coated fuel particles. Electrochemical method with nitrate solution as an electrolyte for fuel element disintegration has been conducted by the Institute of Nuclear and New Energy Technology in Tsinghua University. This method allows a total disintegration of graphite matrix, while still preserving the integrity of TRISO particles. The influences of the pretreatment methods such as heating oxidation of graphite, hydrothermal and oxidants oxidation were investigated in the present work. The experimental results showed that there were no significant effects on increasing the disintegration rate when pretreatment methods were used ahead of electrochemical disintegration. This phenomenon indicated that the fuel elements which were calcined at 1073 K and pressed under 300 MPa are too compact to be broken by these pretreatment methods. And the electrochemical disintegration is an effective but slow method in breaking the graphite matrix. (author)

  3. Alternative Fuels DISI Engine Research ? Autoignition Metrics.

    Energy Technology Data Exchange (ETDEWEB)

    Sjoberg, Carl Magnus Goran [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Vuilleumier, David [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2018-02-01

    Improved engine efficiency is required to comply with future fuel economy standards. Alternative fuels have the potential to enable more efficient engines while addressing concerns about energy security. This project contributes to the science base needed by industry to develop highly efficient direct injection spark igniton (DISI) engines that also beneficially exploit the different properties of alternative fuels. Here, the emphasis is on quantifying autoignition behavior for a range of spark-ignited engine conditions, including directly injected boosted conditions. The efficiency of stoichiometrically operated spark ignition engines is often limited by fuel-oxidizer end-gas autoignition, which can result in engine knock. A fuel’s knock resistance is assessed empirically by the Research Octane Number (RON) and Motor Octane Number (MON) tests. By clarifying how these two tests relate to the autoignition behavior of conventional and alternative fuel formulations, fuel design guidelines for enhanced engine efficiency can be developed.

  4. The Need for a Higher Fuel Efficiency of the Electricity Sector - An Analysis of Opportunities and Barriers

    Energy Technology Data Exchange (ETDEWEB)

    Klimstra, J.

    2007-07-01

    The electricity sector is the single largest user of primary energy in the world. The issues of fuel prices, security of supply and greenhouse gas emissions are therefore closely connected with electricity generation. The total energy efficiency of the electricity sector is only 32.5% so that quick improvements are required. However, the uncertainty over fuel prices and technology preferences is such that most investors are hesitant. The life of existing, often low-efficiency, power plants is therefore extended. At the same time, the demand for electricity is rapidly increasing and the gap between capacity and demand decreases. This paper intends to bring more clarity into the economic and environmental boundary conditions of power plants. The goal is to find an attractive way for rapid efficiency improvement with an even better system reliability without increasing the costs. The paper discusses fuel price developments and the costs of generating technologies in connection with the typical demand pattern of electricity. Ultimately, it appears that local generation, preferably coupled with cogeneration, can be an important part of the solution. (auth)

  5. Hierarchical Load Tracking Control of a Grid-connected Solid Oxide Fuel Cell for Maximum Electrical Efficiency Operation

    DEFF Research Database (Denmark)

    Li, Yonghui; Wu, Qiuwei; Zhu, Haiyu

    2015-01-01

    efficiency operation obtained at different active power output levels, a hierarchical load tracking control scheme for the grid-connected SOFC was proposed to realize the maximum electrical efficiency operation with the stack temperature bounded. The hierarchical control scheme consists of a fast active...... power control and a slower stack temperature control. The active power control was developed by using a decentralized control method. The efficiency of the proposed hierarchical control scheme was demonstrated by case studies using the benchmark SOFC dynamic model......Based on the benchmark solid oxide fuel cell (SOFC) dynamic model for power system studies and the analysis of the SOFC operating conditions, the nonlinear programming (NLP) optimization method was used to determine the maximum electrical efficiency of the grid-connected SOFC subject...

  6. Theory and practice. Possible ways of putting fossil fuels to more efficient use in thermal power stations

    Energy Technology Data Exchange (ETDEWEB)

    Peter, F

    1986-02-01

    In the past decade, the development of fuel and investment costs as it occurred has not given any crucial incentive for a necessary change in thermal efficiency. This can be partly attributed to the high level of technology, but also to the fact that the money spent on efficiency-improving measures increases exponentially for the most part. In any case, it should always be borne in mind in planning a new power station plant that the economic efficiency not only of the plant as a whole must be optimized, but also each individual component and system involved. All efforts to improve economic efficiency in systems and components should be harmonised to fit in with one another.

  7. Role of Engine and Driveline Lubricants in Fuel Efficiency - Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    Bansal, Jai G. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division; Fenske, George [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division; Adkins, Mark [AK Collaborations, Phoenix, AZ (United States)

    2017-09-30

    A virtual workshop was held on May 10, 2017, to obtain input from stakeholders on the role that lubricants can contribute to improving the fuel economy of on-road vehicles – with a focus on legacy vehicles. A ThinkTank collaboration tool was used to facilitate collection and real-time analysis of input provided by the participants. Input was in the form of numeric responses on the amount of fuel economy gains that the respondents felt are possible for light duty (LD) and heavy duty (HD) vehicles, the sources of the gains, and the barriers that will need to be addressed to achieve the fuel economy (FE) gains.

  8. High Efficiency Semi-Fuel Cell Incorporating an Ion Exchange Membrane

    National Research Council Canada - National Science Library

    Medeiros, Maria G; Dow, Eric G; Bessette, Russell R; Yan, Susan G; Dischert, Dwayne W

    2004-01-01

    It is a general purpose and object of the present invention to eliminate the parasitic direct reaction of the catholyte with the metal anode in a semi-fuel cell, thereby improving the overall energy...

  9. Routing strategies for efficient deployment of alternative fuel vehicles for freight delivery.

    Science.gov (United States)

    2017-02-01

    With increasing concerns on environmental issues, recent research on Vehicle Routing Problems : (VRP) has added new factors such as greenhouse gas emissions and alternative fuel vehicles into : the models. In this report, we consider one such promisi...

  10. How Improved Fuel Efficiency May Change U.S. Middle East Policy

    Science.gov (United States)

    2012-03-14

    corporations through diplomatic channels to reduce risks and permit U.S. companies to operate under foreign laws and customs . The federal government should...insufficient Corporate Average Fuel Economy ( CAFE ) standards are two reasons for unchecked demand and the inability to wean the transportation...and development into alternative fuels. Over the past 32 years Congress raised the CAFE standard only 6.9 miles per gallon (mpg), from 17.2 to 24.1

  11. Final Technical Report for Alternative Fuel Source Study-An Energy Efficient and Environmentally Friendly Approach

    Energy Technology Data Exchange (ETDEWEB)

    Zee, Ralph [Auburn University, AL (United States); Schindler, Anton [Auburn University, AL (United States); Duke, Steve [Auburn University, AL (United States); Burch, Thom [Auburn University, AL (United States); Bransby, David [Auburn University, AL (United States); Stafford, Don [Lafarge North America, Inc., Alpharetta, GA (United States)

    2010-08-31

    The objective of this project is to conduct research to determine the feasibility of using alternate fuel sources for the production of cement. Successful completion of this project will also be beneficial to other commercial processes that are highly energy intensive. During this report period, we have completed all the subtasks in the preliminary survey. Literature searches focused on the types of alternative fuels currently used in the cement industry around the world. Information was obtained on the effects of particular alternative fuels on the clinker/cement product and on cement plant emissions. Federal regulations involving use of waste fuels were examined. Information was also obtained about the trace elements likely to be found in alternative fuels, coal, and raw feeds, as well as the effects of various trace elements introduced into system at the feed or fuel stage on the kiln process, the clinker/cement product, and concrete made from the cement. The experimental part of this project involves the feasibility of a variety of alternative materials mainly commercial wastes to substitute for coal in an industrial cement kiln in Lafarge NA and validation of the experimental results with energy conversion consideration.

  12. Handbook of fuel cell performance

    Energy Technology Data Exchange (ETDEWEB)

    Benjamin, T.G.; Camara, E.H.; Marianowski, L.G.

    1980-05-01

    The intent of this document is to provide a description of fuel cells, their performances and operating conditions, and the relationship between fuel processors and fuel cells. This information will enable fuel cell engineers to know which fuel processing schemes are most compatible with which fuel cells and to predict the performance of a fuel cell integrated with any fuel processor. The data and estimates presented are for the phosphoric acid and molten carbonate fuel cells because they are closer to commercialization than other types of fuel cells. Performance of the cells is shown as a function of operating temperature, pressure, fuel conversion (utilization), and oxidant utilization. The effect of oxidant composition (for example, air versus O/sub 2/) as well as fuel composition is examined because fuels provided by some of the more advanced fuel processing schemes such as coal conversion will contain varying amounts of H/sub 2/, CO, CO/sub 2/, CH/sub 4/, H/sub 2/O, and sulfur and nitrogen compounds. A brief description of fuel cells and their application to industrial, commercial, and residential power generation is given. The electrochemical aspects of fuel cells are reviewed. The phosphoric acid fuel cell is discussed, including how it is affected by operating conditions; and the molten carbonate fuel cell is discussed. The equations developed will help systems engineers to evaluate the application of the phosphoric acid and molten carbonate fuel cells to commercial, utility, and industrial power generation and waste heat utilization. A detailed discussion of fuel cell efficiency, and examples of fuel cell systems are given.

  13. Efficient mining of myxobacterial metabolite profiles enabled by liquid chromatography-electrospray ionisation-time-of-flight mass spectrometry and compound-based principal component analysis

    International Nuclear Information System (INIS)

    Krug, Daniel; Zurek, Gabriela; Schneider, Birgit; Garcia, Ronald; Mueller, Rolf

    2008-01-01

    Bacteria producing secondary metabolites are an important source of natural products with highly diverse structures and biological activities. Developing methods to efficiently mine procaryotic secondary metabolomes for the presence of potentially novel natural products is therefore of considerable interest. Modern mass spectrometry-coupled liquid chromatography can effectively capture microbial metabolic diversity with ever improving sensitivity and accuracy. In addition, computational and statistical tools increasingly enable the targeted analysis and exploration of information-rich LC-MS datasets. In this article, we describe the use of such techniques for the characterization of myxobacterial secondary metabolomes. Using accurate mass data from high-resolution ESI-TOF measurements, target screening has facilitated the rapid identification of known myxobacterial metabolites in extracts from nine Myxococcus species. Furthermore, principal component analysis (PCA), implementing an advanced compound-based bucketing approach, readily revealed the presence of further compounds which contribute to variation among the metabolite profiles under investigation. The generation of molecular formulae for putative novel compounds with high confidence due to evaluation of both exact mass position and isotopic pattern, is exemplified as an important key for de-replication and prioritization of candidates for further characterization

  14. Robust inducible Cre recombinase activity in the human malaria parasite Plasmodium falciparum enables efficient gene deletion within a single asexual erythrocytic growth cycle.

    Science.gov (United States)

    Collins, Christine R; Das, Sujaan; Wong, Eleanor H; Andenmatten, Nicole; Stallmach, Robert; Hackett, Fiona; Herman, Jean-Paul; Müller, Sylke; Meissner, Markus; Blackman, Michael J

    2013-05-01

    Asexual blood stages of the malaria parasite, which cause all the pathology associated with malaria, can readily be genetically modified by homologous recombination, enabling the functional study of parasite genes that are not essential in this part of the life cycle. However, no widely applicable method for conditional mutagenesis of essential asexual blood-stage malarial genes is available, hindering their functional analysis. We report the application of the DiCre conditional recombinase system to Plasmodium falciparum, the causative agent of the most dangerous form of malaria. We show that DiCre can be used to obtain rapid, highly regulated site-specific recombination in P. falciparum, capable of excising loxP-flanked sequences from a genomic locus with close to 100% efficiency within the time-span of a single erythrocytic growth cycle. DiCre-mediated deletion of the SERA5 3' UTR failed to reduce expression of the gene due to the existence of alternative cryptic polyadenylation sites within the modified locus. However, we successfully used the system to recycle the most widely used drug resistance marker for P. falciparum, human dihydrofolate reductase, in the process producing constitutively DiCre-expressing P. falciparum clones that have broad utility for the functional analysis of essential asexual blood-stage parasite genes. © 2013 John Wiley & Sons Ltd.

  15. Enabling benchmarking and improving operational efficiency at nuclear power plants through adoption of a common process model: SNPM (standard nuclear performance model)

    International Nuclear Information System (INIS)

    Pete Karns

    2006-01-01

    others. The goal of the SNPM is to give the people maintaining and operating nuclear power stations a common model on which to base their business processes and measure/benchmark themselves against others. The importance of benchmarking and comparing 'apples to apples' has and will continue to safely drive improvement and efficiencies throughout the business. For example, in the mid 1990's it was quite difficult to compare work management statistics and programs between plants. The introduction of several INPO documents, which eventually became the SNPM work management process (AP 928) enabled plants to benchmark and compare information on many aspects of work management, in fact INPO began to evaluate the nuclear plants on their implementation and usage of AP 928. Also, the standardization enabled the identification and benchmarking of innovations in plant processes and performance, which in turn helped to facilitate those innovations being accepted in other plants-thus furthering the cycle of continuous improvement. Using a master plan, all communities of practice are able to identify specific improvement projects and coordinate the implementation of the processes to ensure smooth transitions between the various process interface or intersection points. In essence the nuclear energy industry in the United States is working as one company-driving efficiencies and operational improvements. Key enablers in adopting the best practices like the SNPM are work, asset and supply chain management solutions - both from a functional and a technological point of view. In addition to the importance of supporting industry best practices, there are two additional attributes a nuclear power operating company should evaluate regarding software solutions for work, asset, and supply chain management: breadth of assets managed, and the architecture of solution. (author)

  16. Case Study on Incentive Mechanism of Energy Efficiency Retrofit in Coal-Fueled Power Plant in China

    Directory of Open Access Journals (Sweden)

    Donghai Yuan

    2012-01-01

    Full Text Available An ordinary steam turbine retrofit project is selected as a case study; through the retrofit, the project activities will generate emission reductions within the power grid for about 92,463 tCO2e per annum. The internal rate of return (IRR of the project is only −0.41% without the revenue of carbon credits, for example, CERs, which is much lower than the benchmark value of 8%. Only when the unit price of carbon credit reaches 125 CNY/tCO2, the IRR could reach the benchmark and an effective carbon tax needs to increase the price of carbon to 243 CNY/tce in order to make the project financially feasible. Design of incentive mechanism will help these low efficiency enterprises improve efficiency and reduce CO2 emissions, which can provide the power plants sufficient incentive to implement energy efficiency retrofit project in existing coal-fuel power generation-units, and we hope it will make a good demonstration for the other low efficiency coal-fueled power generation units in China.

  17. Case Study on Incentive Mechanism of Energy Efficiency Retrofit in Coal-Fueled Power Plant in China

    Science.gov (United States)

    Yuan, Donghai; Guo, Xujing; Cao, Yuan; He, Liansheng; Wang, Jinggang; Xi, Beidou; Li, Junqi; Ma, Wenlin; Zhang, Mingshun

    2012-01-01

    An ordinary steam turbine retrofit project is selected as a case study; through the retrofit, the project activities will generate emission reductions within the power grid for about 92,463 tCO2e per annum. The internal rate of return (IRR) of the project is only −0.41% without the revenue of carbon credits, for example, CERs, which is much lower than the benchmark value of 8%. Only when the unit price of carbon credit reaches 125 CNY/tCO2, the IRR could reach the benchmark and an effective carbon tax needs to increase the price of carbon to 243 CNY/tce in order to make the project financially feasible. Design of incentive mechanism will help these low efficiency enterprises improve efficiency and reduce CO2 emissions, which can provide the power plants sufficient incentive to implement energy efficiency retrofit project in existing coal-fuel power generation-units, and we hope it will make a good demonstration for the other low efficiency coal-fueled power generation units in China. PMID:23365532

  18. Case study on incentive mechanism of energy efficiency retrofit in coal-fueled power plant in China.

    Science.gov (United States)

    Yuan, Donghai; Guo, Xujing; Cao, Yuan; He, Liansheng; Wang, Jinggang; Xi, Beidou; Li, Junqi; Ma, Wenlin; Zhang, Mingshun

    2012-01-01

    An ordinary steam turbine retrofit project is selected as a case study; through the retrofit, the project activities will generate emission reductions within the power grid for about 92,463 tCO(2)e per annum. The internal rate of return (IRR) of the project is only -0.41% without the revenue of carbon credits, for example, CERs, which is much lower than the benchmark value of 8%. Only when the unit price of carbon credit reaches 125 CNY/tCO(2), the IRR could reach the benchmark and an effective carbon tax needs to increase the price of carbon to 243 CNY/tce in order to make the project financially feasible. Design of incentive mechanism will help these low efficiency enterprises improve efficiency and reduce CO(2) emissions, which can provide the power plants sufficient incentive to implement energy efficiency retrofit project in existing coal-fuel power generation-units, and we hope it will make a good demonstration for the other low efficiency coal-fueled power generation units in China.

  19. Hierarchical Load Tracking Control of a Grid-Connected Solid Oxide Fuel Cell for Maximum Electrical Efficiency Operation

    Directory of Open Access Journals (Sweden)

    Yonghui Li

    2015-03-01

    Full Text Available Based on the benchmark solid oxide fuel cell (SOFC dynamic model for power system studies and the analysis of the SOFC operating conditions, the nonlinear programming (NLP optimization method was used to determine the maximum electrical efficiency of the grid-connected SOFC subject to the constraints of fuel utilization factor, stack temperature and output active power. The optimal operating conditions of the grid-connected SOFC were obtained by solving the NLP problem considering the power consumed by the air compressor. With the optimal operating conditions of the SOFC for the maximum efficiency operation obtained at different active power output levels, a hierarchical load tracking control scheme for the grid-connected SOFC was proposed to realize the maximum electrical efficiency operation with the stack temperature bounded. The hierarchical control scheme consists of a fast active power control and a slower stack temperature control. The active power control was developed by using a decentralized control method. The efficiency of the proposed hierarchical control scheme was demonstrated by case studies using the benchmark SOFC dynamic model.

  20. Fuel conversion efficiency improvements in a highly boosted spark-ignition engine with ultra-expansion cycle

    International Nuclear Information System (INIS)

    Li, Tie; Zheng, Bin; Yin, Tao

    2015-01-01

    Highlights: • Ultra-expansion cycle SI engine is investigated. • An improvement of 9–26% in BSFC at most frequently operated conditions is obtained. • At high and medium loads, BSFC improvement is attributed to the increased combustion efficiency and reduced exhaust energy. • At low loads, reduction in pumping loss and exhaust energy is the primary contributors to BSFC improvement. • Technical challenge in practical application of this type of engine is discussed. - Abstract: A four-cylinder, intake boosted, port fuel injection (PFI), spark-ignition (SI) engine is modified to a three-cylinder engine with the outer two cylinders working in the conventional four stroke cycle and with the inner cylinder working only with the expansion and exhausting strokes. After calibration and validation of the engine cycle simulation models using the experimental data in the original engine, the performance of the three-cylinder engine with the ultra-expansion cycle is numerically studied. Compared to the original engine, the fuel consumptions under the most-frequently operated conditions are improved by 9–26% and the low fuel consumption area on the operating map are drastically enlarged for the ultra-expansion cycle engine with the proper design. Nonetheless, a higher intake boosting is needed for the ultra-expansion cycle engine to circumvent the significant drop in the wide-open-throttle (WOT) performance, and compression ratio of the combustion cylinder must be reduced to avoid knocking combustion. Despite of the reduced compression ratio, however, the total expansion ratio is increased to 13.8 with the extra expansion of the working gas in the inner cylinder. Compared to the conventional engine, the theoretical thermal efficiency is therefore increased by up to above 4.0% with the ultra-expansion cycle over the most load range. The energy balance analysis shows that the increased combustion efficiency, reduced exhaust energy and the extra expansion work in the

  1. Integrated high-efficiency Pt/carbon nanotube arrays for PEM fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Weimin; Minett, Andrew I.; Zhao, Jie; Razal, Joselito M.; Wallace, Gordon G.; Romeo, Tony; Chen, Jun [Intelligent Polymer Research Institute, AIIM Facility, Innovation Campus, University of Wollongong, NSW 2522 (Australia); Gao, Mei [Division of Materials Science and Engineering, CSIRO, Bayview Ave, Clayton, VIC 3168 (Australia)

    2011-07-15

    A facile strategy to deposit Pt nanoparticles with various metal-loading densities on vertically aligned carbon nanotube (ACNT) arrays as electrocatalysts for proton exchange membrane (PEM) fuel cells is described. The deposition is achieved by electrostatic adsorption of the Pt precursor on the positively charged polyelectrolyte functionalized ACNT arrays and subsequent reduction by L-ascorbic acid. The application of the aligned electrocatalysts in fuel cells is realized by transferring from a quartz substrate to nafion membrane using a hot-press procedure to fabricate the membrane electrode assembly (MEA). It is shown that the MEA with vertically aligned structured electrocatalysts provides better Pt utilization than that with Pt on conventional carbon nanotubes or carbon black, resulting in higher fuel cell performance. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  2. Decomposing Fuel Economy and Greenhouse Gas Regulatory Standards in the Energy Conversion Efficiency and Tractive Energy Domain

    Energy Technology Data Exchange (ETDEWEB)

    Pannone, Greg [Novation Analytics; Thomas, John F [ORNL; Reale, Michael [Novation Analytics; Betz, Brian [Novation Analytics

    2017-01-01

    The three foundational elements that determine mobile source energy use and tailpipe carbon dioxide (CO2) emissions are the tractive energy requirements of the vehicle, the on-cycle energy conversion efficiency of the propulsion system, and the energy source. The tractive energy requirements are determined by the vehicle's mass, aerodynamic drag, tire rolling resistance, and parasitic drag. Oncycle energy conversion of the propulsion system is dictated by the tractive efficiency, non-tractive energy use, kinetic energy recovery, and parasitic losses. The energy source determines the mobile source CO2 emissions. For current vehicles, tractive energy requirements and overall energy conversion efficiency are readily available from the decomposition of test data. For future applications, plausible levels of mass reduction, aerodynamic drag improvements, and tire rolling resistance can be transposed into the tractive energy domain. Similarly, by combining thermodynamic, mechanical efficiency, and kinetic energy recovery fundamentals with logical proxies, achievable levels of energy conversion efficiency can be established to allow for the evaluation of future powertrain requirements. Combining the plausible levels of tractive energy and on-cycle efficiency provides a means to compute sustainable vehicle and propulsion system scenarios that can achieve future regulations. Using these principles, the regulations established in the United States (U.S.) for fuel consumption and CO2 emissions are evaluated. Fleet-level scenarios are generated and compared to the technology deployment assumptions made during rule-making. When compared to the rule-making assumptions, the results indicate that a greater level of advanced vehicle and propulsion system technology deployment will be required to achieve the model year 2025 U.S. standards for fuel economy and CO2 emissions.

  3. Developing the Model of Fuel Injection Process Efficiency Analysis for Injector for Diesel Engines

    Science.gov (United States)

    Anisimov, M. Yu; Kayukov, S. S.; Gorshkalev, A. A.; Belousov, A. V.; Gallyamov, R. E.; Lysenko, Yu D.

    2018-01-01

    The article proposes an assessment option for analysing the quality of fuel injection by the injector constituting the development of calculation blocks in a common injector model within LMS Imagine.Lab AMESim. The parameters of the injector model in the article correspond to the serial injector Common Rail-type with solenoid. The possibilities of this approach are demonstrated with providing the results using the example of modelling the modified injector. Following the research results, the advantages of the proposed approach to analysing assessing the fuel injection quality were detected.

  4. Fuel conversion characteristics of black liquor and pyrolysis oil mixture for efficient gasification with inherent catalyst

    OpenAIRE

    Bach Oller, Albert; Furusjö, Erik; Umeki, Kentaro

    2014-01-01

    This paper describes the technical feasibility of a catalytic co-gasification process using a mixture of black liquor (BL) and pyrolysis oil (PO). A technical concern is if gasifiers can be operated at low temperature (~1000 ºC) without problems of tar, soot or char, as is the case for pure BL due to the catalytic effect of fuel alkali. Hence, we investigated fuel conversion characteristics of BL/PO mixture: conversion of single droplet in flame, and char gasification reactivity. 20wt.% (BP20...

  5. Improving the cathode of a microbial fuel cell for efficient electricity production

    NARCIS (Netherlands)

    Heijne, ter A.

    2010-01-01

    The worldwide demand for energy is increasing. At the same time, energy rich wastewaters are currently purified by oxygen supply, which costs a lot of energy. The Microbial Fuel Cell is a new technology that offers advantages in both directions: it produces electricity while purifying wastewaters.

  6. Competing for development : a case study of fuel-efficient stoves for Darfur

    International Nuclear Information System (INIS)

    Abdelnour, S.; Branzei, O.

    2008-01-01

    This paper discussed the Darfur Stoves Project. The project was designed to provide local support to non-government organizations (NGOs) to set up production facilities capable of producing 100 stoves per day. The Berkeley-Darfur stove design was based on a survey conducted in Darfur of cooking methods, tools, household fuels, and food requirements. The stove was designed to perform well in windy conditions. A pilot production facility was conducted to ensure that the stoves were easily built and assembled using simple hand tools. The stoves save the average family $250 per year in fuel wood and labour costs. The project is now examining methods of setting up multiple full-scale assembly shops to ensure that 300,000 stoves are built and distributed to households and displaced communities in the Darfur region. The need to save fuel wood has grown since the onset of armed conflict in the region. The combined concerns of deforestation, starvation, and violence against women as they searched for fuel wood has become a central concern in the region. The stove design is one of several designs currently being adopted by development agencies in the region. 32 refs., 11 figs

  7. 48 CFR 970.5223-5 - DOE motor vehicle fleet fuel efficiency.

    Science.gov (United States)

    2010-10-01

    ... and Contract Clauses for Management and Operating Contracts 970.5223-5 DOE motor vehicle fleet fuel..., insert the following clause in contracts providing for Contractor management of the motor vehicle fleet... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false DOE motor vehicle fleet...

  8. Cost and Fuel Efficient SCR-only Solution for post-2010 HD Emission Standards

    NARCIS (Netherlands)

    Cloudt, R.P.M.; Willems, F.P.T.; Heijden, van der P.

    2009-01-01

    A promising SCR-only solution is presented to meetpost-2010 NOx emission targets for heavy dutyapplications. The proposed concept is based on anengine from a EURO IV SCR application, which isconsidered optimal with respect to fuel economy andcosts. The addition of advanced SCR after

  9. Cost and fuel efficient SCR-only solution for post-2010 HD emission standards

    NARCIS (Netherlands)

    Cloudt, R.P.M.; Willems, F.P.T.; Heijden, P.V.A.M. van der

    2009-01-01

    A promising SCR-only solution is presented to meet post-2010 NOx emission targets for heavy duty applications. The proposed concept is based on an engine from a EURO IV SCR application, which is considered optimal with respect to fuel economy and costs. The addition of advanced SCR after treatment

  10. High efficiency isolated DC/DC converter inherently optimized for fuel cell applications

    DEFF Research Database (Denmark)

    Petersen, Lars Press; Jensen, Lasse Crone; Larsen, Martin Norgaard

    2013-01-01

    The isolated full-bridge boost converter has been suggested as the best choice for fuel cell applications. Comparisons have been carried out in the literature using both stress factors and experimental verified designs to determine the optimal converter. Never the less, this paper suggests...

  11. Competing for development : a case study of fuel-efficient stoves for Darfur

    Energy Technology Data Exchange (ETDEWEB)

    Abdelnour, S.; Branzei, O. [Western Ontario Univ., London, ON (Canada). Richard Ivey School of Business

    2008-07-01

    This paper discussed the Darfur Stoves Project. The project was designed to provide local support to non-government organizations (NGOs) to set up production facilities capable of producing 100 stoves per day. The Berkeley-Darfur stove design was based on a survey conducted in Darfur of cooking methods, tools, household fuels, and food requirements. The stove was designed to perform well in windy conditions. A pilot production facility was conducted to ensure that the stoves were easily built and assembled using simple hand tools. The stoves save the average family $250 per year in fuel wood and labour costs. The project is now examining methods of setting up multiple full-scale assembly shops to ensure that 300,000 stoves are built and distributed to households and displaced communities in the Darfur region. The need to save fuel wood has grown since the onset of armed conflict in the region. The combined concerns of deforestation, starvation, and violence against women as they searched for fuel wood has become a central concern in the region. The stove design is one of several designs currently being adopted by development agencies in the region. 32 refs., 11 figs.

  12. Stable and Efficient Advanced Oxygen Reduction Alloy Catalysts for PEM Fuel Cells, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Human exploration of space demands highly efficient, light-weight, long lifetime and maintenance-free power generation systems. Energy storage applications,...

  13. Advanced cycle efficiency: Generating 40% more power from the nuclear fuel

    Energy Technology Data Exchange (ETDEWEB)

    Duffey, Romney B.; Leung, Laurence

    2010-09-15

    The introduction of supercritical water (SCW) nuclear power plants (NPPs) would improve the overall plant efficiency significantly compared to currently deployed systems. This improvement is attributed to the increase in plant operating conditions. In addition, the implementation of the reheat-channel option into the CANDU SCW NPPs would further enhance the efficiency. Overall, the combination of higher operating conditions and reheat-channel option would lead to overall plant efficiency of about 50% for the CANDU SCW NPPs, compared to 33--35% for currently deployed systems. This represents a whopping 40% improvement in efficiency.

  14. Potential long-term impacts of changes in US vehicle fuel efficiency standards

    International Nuclear Information System (INIS)

    Bezdek, Roger H.; Wendling, Robert M.

    2005-01-01

    Changes in corporate average fuel economy (CAFE) standards have not been made due, in part, to concerns over their negative impact on the economy and jobs. This paper simulates the effects of enhanced CAFE standards through 2030 and finds that such changes could increase GDP and create 300,000 jobs distributed widely across states, industries, and occupations. In addition, enhanced CAFE standards could, each year, reduce US oil consumption by 30 billion gallons, save drivers $40 billion, and reduce US greenhouse gas emissions by 100 million tons. However, there is no free lunch. There would be widespread job displacement within many industries, occupations, and states, and increased CAFE standards require that fuel economy be given priority over other vehicle improvements, increase the purchase price of vehicles, require manufacturers to produce vehicles that they otherwise would not, and require consumers to purchase vehicles that would not exist except for CAFE

  15. Development of fuel cycles with new fuel with 8.9 mm external diameter for VVER-440. Preliminary assessment of operating efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Gagarinskiy, Alexey [National Research Centre ' ' Kurchatov Institute' ' , Moscow (Russian Federation)

    2017-09-15

    Since the introduction of VVERs-440, their fuel assemblies are subject to ongoing improvements. Until now, the basic structural parameters of fuel, such as rod diameter of 9.1 mm, have never changed. This paper focuses on computational estimates of basic neutronic parameters of the fuel cycle that involves assemblies consisting of fuel rods with diameter reduced to 8.9 mm.

  16. Fuel and nuclear fuel cycle

    International Nuclear Information System (INIS)

    Prunier, C.

    1998-01-01

    The nuclear fuel is studied in detail, the best choice and why in relation with the type of reactor, the properties of the fuel cans, the choice of fuel materials. An important part is granted to the fuel assembly of PWR type reactor and the performances of nuclear fuels are tackled. The different subjects for research and development are discussed and this article ends with the particular situation of mixed oxide fuels ( materials, behavior, efficiency). (N.C.)

  17. Energy efficiency assessment by life cycle simulation of cassava-based fuel ethanol for automotive use in Chinese Guangxi context

    International Nuclear Information System (INIS)

    Yu Suiran; Tao Jing

    2009-01-01

    Interest has been renewed in bio-ethanol products for their contributions in moderating oil crises. So far, most research on bio-ethanol in China is based on pilot-level experimental studies. But this work only discloses information regarding material balances and reached yields without any further energy analysis. This paper aims to assess the energy efficiency of the cassava-based fuel ethanol (KFE) product from southwest China. For the purpose of a life cycle study of the KFE product as replacement transportation fuel, the study chose a 'vehicle fueled by cassava-based E10 (a blend of 10% ethanol and 90% gasoline by volume)' as the subject and accordingly defined the scope of this study. Then, the life cycle model of the KFE product concerning energetically relevant in- and outputs was built. Due to variations in data collected, as well as some estimates and assumptions used in this study, the Monte Carlo method was introduced to develop the statistical dispersion of calculated outputs of the assessing model. Assessment results show that, within the boundary of this study, KFE has a positive net energy value, with an energy ratio of around 0.70 MJ/MJ, which means 7 MJ into the processing for each MJ of KFE output

  18. Highly efficient visible light photocatalytic reduction of CO2 to hydrocarbon fuels by Cu-nanoparticle decorated graphene oxide.

    Science.gov (United States)

    Shown, Indrajit; Hsu, Hsin-Cheng; Chang, Yu-Chung; Lin, Chang-Hui; Roy, Pradip Kumar; Ganguly, Abhijit; Wang, Chen-Hao; Chang, Jan-Kai; Wu, Chih-I; Chen, Li-Chyong; Chen, Kuei-Hsien

    2014-11-12

    The production of renewable solar fuel through CO2 photoreduction, namely artificial photosynthesis, has gained tremendous attention in recent times due to the limited availability of fossil-fuel resources and global climate change caused by rising anthropogenic CO2 in the atmosphere. In this study, graphene oxide (GO) decorated with copper nanoparticles (Cu-NPs), hereafter referred to as Cu/GO, has been used to enhance photocatalytic CO2 reduction under visible-light. A rapid one-pot microwave process was used to prepare the Cu/GO hybrids with various Cu contents. The attributes of metallic copper nanoparticles (∼4-5 nm in size) in the GO hybrid are shown to significantly enhance the photocatalytic activity of GO, primarily through the suppression of electron-hole pair recombination, further reduction of GO's bandgap, and modification of its work function. X-ray photoemission spectroscopy studies indicate a charge transfer from GO to Cu. A strong interaction is observed between the metal content of the Cu/GO hybrids and the rates of formation and selectivity of the products. A factor of greater than 60 times enhancement in CO2 to fuel catalytic efficiency has been demonstrated using Cu/GO-2 (10 wt % Cu) compared with that using pristine GO.

  19. Strategies for merging microbial fuel cell technologies in water desalination processes: Start-up protocol and desalination efficiency assessment

    Science.gov (United States)

    Borjas, Zulema; Esteve-Núñez, Abraham; Ortiz, Juan Manuel

    2017-07-01

    Microbial Desalination Cells constitute an innovative technology where microbial fuel cell and electrodialysis merge in the same device for obtaining fresh water from saline water with no energy-associated cost for the user. In this work, an anodic biofilm of the electroactive bacteria Geobacter sulfurreducens was able to efficiently convert the acetate present in synthetic waste water into electric current (j = 0.32 mA cm-2) able to desalinate water. .Moreover, we implemented an efficient start-up protocol where desalination up to 90% occurred in a desalination cycle (water production:0.308 L m-2 h-1, initial salinity: 9 mS cm-1, final salinity: osmosis (RO) or reverse electrodialysis.

  20. Heavy component of spent nuclear fuel: Efficiency of model-substance ionization by electron-induced discharge

    Energy Technology Data Exchange (ETDEWEB)

    Antonov, N. N., E-mail: antonovnickola@gmail.com; Gavrikov, A. V.; Samokhin, A. A.; Smirnov, V. P. [Russian Academy of Sciences, High Energy Density Research Center, Joint Institute for High Temperatures (Russian Federation)

    2016-12-15

    The method of plasma separation of spent nuclear fuel can be tested with a model substance which has to be transformed from the condensed to plasma state. For this purpose, electron-induced discharge in lead vapor injected into the interelectrode gap is simulated using the kinetic approach. The ionization efficiency, the electrostatic-potential distribution, and those of the ion and electron densities in the discharge gap are derived as functions of the discharge-current density and concentration of the vapor of the model substance. Given a discharge-current density of 3.5 A/cm{sup 2} and a lead-vapor concentration of 2 × 10{sup 12} cm{sup –3}, the simulated ionization efficiency proves to be nearly 60%. The discharge in lead vapor is also investigated experimentally.

  1. Catalytic Fuel Conversion Facility

    Data.gov (United States)

    Federal Laboratory Consortium — This facility enables unique catalysis research related to power and energy applications using military jet fuels and alternative fuels. It is equipped with research...

  2. Efficient utilization of waste date pits for the synthesis of green diesel and jet fuel fractions

    International Nuclear Information System (INIS)

    Al-Muhtaseb, Ala’a H.; Jamil, Farrukh; Al-Haj, Lamya; Al-Hinai, Mohab A.; Baawain, Mahad; Myint, Myo Tay Zar; Rooney, David

    2016-01-01

    Highlights: • Active catalysts Pt/C and Pd/C were developed from waste date pits. • Catalysts showed good activity in hydrodeoxygenation of date pit oil to alkane fuels. • The liquid product fractions lay within the range of the jet fuel and green diesel. • Green diesel fraction obtained by Pd/C was 72.03% and jet fuel was 30.39%. • Date pits can be a promising platform for the production of catalysts and biofuels. - Abstract: Date pits are considered one of the major agricultural wastes in Oman. The present work involves the synthesis of active catalysts from waste date pits carbon produced by carbonization and impregnation with Pt and Pd metals. Synthesized catalysts Pt/C and Pd/C were characterized by XRD, SEM, TEM, EDX, BET and XPS. The activity of the catalysts’ performance was evaluated by the hydrodeoxygenation of date pits oil for the production of second-generation biofuels, which includes jet fuel and green diesel fractions. Results indicate that the synthesized catalysts were highly active for the hydrodeoxygenation of date pits oil. Based on the elemental analysis, the degree of deoxygenation (DOD) of product oil was 97.5% and 89.4% for the Pd/C and Pt/C catalysts respectively. The high DOD was also confirmed by product analyses that mainly consist of paraffinic hydrocarbons. Results also showed that between the two catalysts, Pd/C showed a higher activity towards hydrodeoxygenation, a conclusion that was based on the high DOD of the product oil due to hydrocarbons formation. Based on the type of components in the product oil, the maximum fraction of hydrocarbons formed lay within the range of 72.03% and 72.78% green diesel, and 30.39% and 28.25% jet fuel using Pd/C and Pt/C catalysts respectively. It can be concluded that waste date pits can be a promising platform for the production of catalysts and biofuels.

  3. Durability and efficiency tests for direct methanol fuel cell's long-term performance assessment

    International Nuclear Information System (INIS)

    Yeh, Pulin; Chang, Chu Hsiang; Shih, Naichien; Yeh, Naichia

    2016-01-01

    This research assessed the long-term performance of direct methanol fuel cells. The experiment was performed at room temperature using 0.51 mol/L ∼0.651 mol/L methanol with a fuel consumption rate of 0.8 ± 0.1 cc/Wh at stack temperature of 60 °C–70 °C. DuPont Nafion115 proton exchange membrane was used as the base material of MEA (membrane electrode assembly), which is then examined via a series of processes that include I−V curve test, humidity cycle test, load cycle test, and hydrogen penetration test. The study employs membrane modification and cell structure adjustment approaches to reduce the methanol crossover in the cathode and identify the cell performance effect of the carbon paper gas diffusion layer. The test results indicated an efficiency of 25% can be achieved with a three-piece MEA assembly. According to the durability test, the stack power-generation efficiency has maintained at 15%–25% level. With such efficiency, the stack voltage output has been able to stay above 7.8-V for over 5000 h. This result is in line with industry standard. - Highlights: • Assess DMFC performance under non-optimal conditions for production readiness. • Output of 26-cell DMFC stack stays beyond 7.8v after 5000 operation hours. • Power-generation efficiency of 26-cell DMFC stack maintains between 15%–20%.

  4. Highly efficient transition metal and nitrogen co-doped carbide-derived carbon electrocatalysts for anion exchange membrane fuel cells

    Science.gov (United States)

    Ratso, Sander; Kruusenberg, Ivar; Käärik, Maike; Kook, Mati; Puust, Laurits; Saar, Rando; Leis, Jaan; Tammeveski, Kaido

    2018-01-01

    The search for an efficient electrocatalyst for oxygen reduction reaction (ORR) to replace platinum in fuel cell cathode materials is one of the hottest topics in electrocatalysis. Among the many non-noble metal catalysts, metal/nitrogen/carbon composites made by pyrolysis of cheap materials are the most promising with control over the porosity and final structure of the catalyst a crucial point. In this work we show a method of producing a highly active ORR catalyst in alkaline media with a controllable porous structure using titanium carbide derived carbon as a base structure and dicyandiamide along with FeCl3 or CoCl2 as the dopants. The resulting transition metal-nitrogen co-doped carbide derived carbon (M/N/CDC) catalyst is highly efficient for ORR electrocatalysis with the activity in 0.1 M KOH approaching that of commercial 46.1 wt.% Pt/C. The catalyst materials are also investigated by scanning electron microscopy, Raman spectroscopy and X-ray photoelectron spectroscopy to characterise the changes in morphology and composition causing the raise in electrochemical activity. MEA performance of M/N/CDC cathode materials in H2/O2 alkaline membrane fuel cell is tested with the highest power density reached being 80 mW cm-2 compared to 90 mW cm-2 for Pt/C.

  5. Development of a high-efficiency hydrogen generator for fuel cells for distributed power generation

    Energy Technology Data Exchange (ETDEWEB)

    Duraiswamy, K.; Chellappa, Anand [Intelligent Energy, 2955 Redondo Ave., Long Beach, CA 90806 (United States); Smith, Gregory; Liu, Yi; Li, Mingheng [Department of Chemical and Materials Engineering, California State Polytechnic University, Pomona, CA 91768 (United States)

    2010-09-15

    A collaborative effort between Intelligent Energy and Cal Poly Pomona has developed an adsorption enhanced reformer (AER) for hydrogen generation for use in conjunction with fuel cells in small sizes. The AER operates at a lower temperature (about 500 C) and has a higher hydrogen yield and purity than those in the conventional steam reforming. It employs ceria supported rhodium as the catalyst and potassium-promoted hydrotalcites to remove carbon dioxide from the products. A novel pulsing feed concept is developed for the AER operation to allow a deeper conversion of the feedstock to hydrogen. Continuous production of near fuel-cell grade hydrogen is demonstrated in the AER with four packed beds running alternately. In the best case of methane reforming, the overall conversion to hydrogen is 92% while the carbon dioxide and carbon monoxide concentrations in the production stream are on the ppm level. The ratio of carbon dioxide in the regeneration exhaust to the one in the product stream is on the order of 10{sup 3}. (author)

  6. Development of Modified Pag (Polyalkylene Glycol) High VI High Fuel Efficient Lubricant for LDV Applications

    Energy Technology Data Exchange (ETDEWEB)

    Gangopadhyay, Arup [Ford Motor Company, Dearborn, MI (United States); McWatt, D. G. [Ford Motor Company, Dearborn, MI (United States); Zdrodowski, R. J. [Ford Motor Company, Dearborn, MI (United States); Liu, Zak [Ford Motor Company, Dearborn, MI (United States); Elie, Larry [Ford Motor Company, Dearborn, MI (United States); Simko, S. J. [Ford Motor Company, Dearborn, MI (United States); Erdemir, Ali [Argonne National Lab. (ANL), Argonne, IL (United States); Ramirez, Giovanni [Argonne National Lab. (ANL), Argonne, IL (United States); Cuthbert, J. [Dow Chemical Company, Midland, MI (United States); Hock, E. D. [Dow Chemical Company, Midland, MI (United States)

    2015-09-30

    Engine oils play a critical role in friction reduction. Improvements in engine oil technology steadily improved fuel economy as the industry moved through ILSAC GF-1 to GF-5 specifications. These improvements were influenced by changes in base oil chemistry, development of new friction modifiers and their treat levels, and the total additive package consisting of various other components. However, the improvements are incremental and further fuel consumption reduction opportunities are becoming more challenging. Polyalkylene glycol (PAG) based engine oils are being explored as a step forward for significant fuel consumption reduction. Although PAG fluids are used in many industrial applications, its application as an engine oil has been explored in a limited way. The objective of this project is to deep dive in exploring the applicability of PAG technology in engine oil, understanding the benefits, and limitations, elucidating the mechanism(s) for friction benefits, if any, and finally recommending how to address any limitations. The project was designed in four steps, starting with selection of lubricant technology, followed by friction and wear evaluations in laboratory bench tests which are relatively simple and inexpensive and also served as a screener for further evaluation. Selected formulations were chosen for more complex engine component level tests i.e., motored valvetrain friction and wear, piston ring friction using a motored single cylinder, and motored engine tests. A couple of formulations were further selected based on component level tests for engine dyno tests i.e., Sequence VID (ASTM D6709) for fuel economy, Sequence IVA (ASTM D6891) for valvetrain wear, and Sequence VG (ASTM D6593) for sludge and varnish protection. These are some of the industry standard tests required for qualifying engine oils. Out of these tests, a single PAG oil was selected for chassis roll dynamometer tests for fuel economy and emission measurements using FTP (Federal

  7. Improving domestic wastewater treatment efficiency with constructed wetland microbial fuel cells: Influence of anode material and external resistance.

    Science.gov (United States)

    Corbella, Clara; Puigagut, Jaume

    2018-08-01

    For the past few years, there has been an increasing interest in the operation of constructed wetlands as microbial fuel cells (CW-MFCs) for both the improvement of wastewater treatment efficiency and the production of energy. However, there is still scarce information on design and operation aspects to maximize CW-MFCs efficiency, especially for the treatment of real domestic wastewater. The aim of this study was to quantify the extent of treatment efficiency improvement carried out by membrane-less MFCs simulating a core of a shallow un-planted horizontal subsurface flow constructed wetland. The influence of the external resistance (50, 220, 402, 604 and 1000Ω) and the anode material (graphite and gravel) on treatment efficiency improvement were addressed. To this purpose, 6 lab-scale membrane-less MFCs were set-up and loaded in batch mode with domestic wastewater for 13weeks. Results showed that 220Ω was the best operation condition for maximising MFCs treatment efficiency, regardless the anode material employed. Gravel-based anode MFCs operated at closed circuit showed ca. 18%, 15%, 31% and 25% lower effluent concentration than unconnected MFCs to the COD, TOC, PO 4 -3 and NH 4 + -N, respectively. Main conclusion of the present work is that constructed wetlands operated as MFCs is a promising strategy to improve domestic wastewater treatment efficiency. However, further studies at pilot scale under more realistic conditions (such as planted systems operated under continuous mode) shall be performed to confirm the findings here reported. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. A New Very-High-Efficiency R4 Converter for High-Power Fuel Cell Applications

    DEFF Research Database (Denmark)

    Nymand, Morten; Andersen, Michael Andreas E.

    2009-01-01

    of fullbridge switching stages and power transformers, operate in parallel on primary side and in series on secondary side. Current sharing is guaranteed by series connection of transformer secondary windings and three small cascaded current balancing transformers on primary side. The detailed design of a 10 k......W prototype converter is presented. Input voltage range is 30-60 V and output voltage is 800 V. Test results, including voltage- and current waveforms and efficiency measurements, are presented. A record high converter efficiency of 98.2 % is achieved. The proposed R4 boost converter thus constitutes a low...

  9. Mechanisms of yeast stress tolerance and its manipulation for efficient fuel ethanol production.

    Science.gov (United States)

    Zhao, X Q; Bai, F W

    2009-10-12

    Yeast strains of Saccharomyces cerevisiae have been extensively studied in recent years for fuel ethanol production, in which yeast cells are exposed to various stresses such as high temperature, ethanol inhibition, and osmotic pressure from product and substrate sugars as well as the inhibitory substances released from the pretreatment of lignocellulosic biomass. An in-depth understanding of the mechanism of yeast stress tolerance contributes to breeding more robust strains for ethanol production, especially under very high gravity conditions. Taking advantage of the "omics" technology, the stress response and defense mechanism of yeast cells during ethanol fermentation were further explored, and the newly emerged tools such as genome shuffling and global transcription machinery engineering have been applied to breed stress resistant yeast strains for ethanol production. In this review, the latest development of stress tolerance mechanisms was focused, and improvement of yeast stress tolerance by both random and rational tools was presented.

  10. Pronounced Effects of a Triazine Core on Photovoltaic Performance-Efficient Organic Solar Cells Enabled by a PDI Trimer-Based Small Molecular Acceptor.

    Science.gov (United States)

    Duan, Yuwei; Xu, Xiaopeng; Yan, He; Wu, Wenlin; Li, Zuojia; Peng, Qiang

    2017-02-01

    A novel-small molecular acceptor with electron-deficient 1,3,5-triazine as the core and perylene diimides as the arms is developed as the acceptor material for efficient bulk heterojunction organic solar cells with an efficiency of 9.15%. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Efficient Near-Infrared-Transparent Perovskite Solar Cells Enabling Direct Comparison of 4-Terminal and Monolithic Perovskite/Silicon Tandem Cells

    OpenAIRE

    Werner, Jérémie; Barraud, Loris; Walter, Arnaud; Bräuninger, Matthias; Sahli, Florent; Sacchetto, Davide; Tétreault, Nicolas; Paviet-Salomon, Bertrand; Moon, Soo-Jin; Allebé, Christophe; Despeisse, Matthieu; Nicolay, Sylvain; De Wolf, Stefaan; Niesen, Bjoern; Ballif, Christophe

    2016-01-01

    Combining market-proven silicon solar cell technology with an efficient wide band gap top cell into a tandem device is an attractive approach to reduce the cost of photovoltaic systems. For this, perovskite solar cells are promising high-efficiency top cell candidates, but their typical device size (

  12. Prospects for and problems of using light-water supercritical-pressure coolant in nuclear reactors in order to increase the efficiency of the nuclear fuel cycle

    International Nuclear Information System (INIS)

    Alekseev, P. N.; Semchenkov, Yu. M.; Sedov, A. A.; Subbotin, S. A.; Chibinyaev, A. V.

    2011-01-01

    Trends in the development of the power sector of the Russian and world power industries both at present time and in the near future are analyzed. Trends in the rise of prices for reserves of fossil and nuclear fuels used for electricity production are compared. An analysis of the competitiveness of electricity production at nuclear power plants as compared to the competitiveness of electricity produced at coal-fired and natural-gas-fired thermal power plants is performed. The efficiency of the open nuclear fuel cycle and various versions of the closed nuclear fuel cycle is discussed. The requirements on light-water reactors under the scenario of dynamic development of the nuclear power industry in Russia are determined. Results of analyzing the efficiency of fuel utilization for various versions of vessel-type light-water reactors with supercritical coolant are given. Advantages and problems of reactors with supercritical-pressure water are listed.

  13. Carbon-doped SnS2 nanostructure as a high-efficiency solar fuel catalyst under visible light.

    Science.gov (United States)

    Shown, Indrajit; Samireddi, Satyanarayana; Chang, Yu-Chung; Putikam, Raghunath; Chang, Po-Han; Sabbah, Amr; Fu, Fang-Yu; Chen, Wei-Fu; Wu, Chih-I; Yu, Tsyr-Yan; Chung, Po-Wen; Lin, M C; Chen, Li-Chyong; Chen, Kuei-Hsien

    2018-01-12

    Photocatalytic formation of hydrocarbons using solar energy via artificial photosynthesis is a highly desirable renewable-energy source for replacing conventional fossil fuels. Using an L-cysteine-based hydrothermal process, here we synthesize a carbon-doped SnS 2 (SnS 2 -C) metal dichalcogenide nanostructure, which exhibits a highly active and selective photocatalytic conversion of CO 2 to hydrocarbons under visible-light. The interstitial carbon doping induced microstrain in the SnS 2 lattice, resulting in different photophysical properties as compared with undoped SnS 2 . This SnS 2 -C photocatalyst significantly enhances the CO 2 reduction activity under visible light, attaining a photochemical quantum efficiency of above 0.7%. The SnS 2 -C photocatalyst represents an important contribution towards high quantum efficiency artificial photosynthesis based on gas phase photocatalytic CO 2 reduction under visible light, where the in situ carbon-doped SnS 2 nanostructure improves the stability and the light harvesting and charge separation efficiency, and significantly enhances the photocatalytic activity.

  14. Efficient H2O2/CH3COOH oxidative desulfurization/denitrification of liquid fuels in sonochemical flow-reactors.

    Science.gov (United States)

    Calcio Gaudino, Emanuela; Carnaroglio, Diego; Boffa, Luisa; Cravotto, Giancarlo; Moreira, Elizabeth M; Nunes, Matheus A G; Dressler, Valderi L; Flores, Erico M M

    2014-01-01

    The oxidative desulfurization/denitrification of liquid fuels has been widely investigated as an alternative or complement to common catalytic hydrorefining. In this process, all oxidation reactions occur in the heterogeneous phase (the oil and the polar phase containing the oxidant) and therefore the optimization of mass and heat transfer is of crucial importance to enhancing the oxidation rate. This goal can be achieved by performing the reaction in suitable ultrasound (US) reactors. In fact, flow and loop US reactors stand out above classic batch US reactors thanks to their greater efficiency and flexibility as well as lower energy consumption. This paper describes an efficient sonochemical oxidation with H2O2/CH3COOH at flow rates ranging from 60 to 800 ml/min of both a model compound, dibenzotiophene (DBT), and of a mild hydro-treated diesel feedstock. Four different commercially available US loop reactors (single and multi-probe) were tested, two of which were developed in the authors' laboratory. Full DBT oxidation and efficient diesel feedstock desulfurization/denitrification were observed after the separation of the polar oxidized S/N-containing compounds (S≤5 ppmw, N≤1 ppmw). Our studies confirm that high-throughput US applications benefit greatly from flow-reactors. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Flexible Nanosomes (SECosomes) Enable Efficient siRNA Delivery in Cultured Primary Skin Cells and in the Viable Epidermis of Ex Vivo Human Skin

    NARCIS (Netherlands)

    Geusens, Barbara; Van Gele, Mireille; Braat, Sien; De Smedt, Stefaan C.; Stuart, Marc C. A.; Prow, Tarl W.; Sanchez, Washington; Roberts, Michael S.; Sanders, Niek N.; Lambert, Jo

    2010-01-01

    The extent to which nanoscale-engineered systems cross intact human skin and can exert pharmacological effects in viable epidermis is controversial. This research seeks to develop a new lipid-based nanosome that enables the effective delivery of siRNA into human skin. The major finding is that an

  16. Resource-efficient ILC for LTI/LTV systems through LQ tracking and stable inversion: enabling large feedforward tasks on a position-dependent printer

    NARCIS (Netherlands)

    van Zundert, J.; Bolder, J.J.; Koekebakker, S.H.; Oomen, T.A.E.

    Iterative learning control (ILC) enables high performance for systems that execute repeating tasks. Norm-optimal ILC based on lifted system representations provides an analytic expression for the optimal feedforward signal. However, for large tasks the computational load increases rapidly for

  17. Field test of radioactive high efficiency filter and filter exchange techniques of fuel cycle examination facility

    International Nuclear Information System (INIS)

    Hwang, Yong Hwa; Lee, Hyung Kwon; Chun, Young Bum; Park, Dae Gyu; Ahn, Sang Bok; Chu, Yong Sun; Kim, Eun Ka.

    1997-12-01

    The development of high efficiency filter was started to protect human beings from the contamination of radioactive particles, toxic gases and bacillus, and its gradual performance increment led to the fabrication of Ultra Low Penetration Air Filter (ULPA) today. The application field of ULPA has been spread not only to the air conditioning of nuclear power facilities, semiconductor industries, life science, optics, medical care and general facilities but also to the core of ultra-precision facilities. Periodic performance test on the filters is essential to extend its life-time through effective maintenance. Especially, the bank test on HEPA filter of nuclear facilities handling radioactive materials is required for environmental safety. Nowadays, the bank test technology has been reached to the utilization of a minimized portable detecting instruments and the evaluation techniques can provide high confidence in the area of particle distribution and leakage test efficiency. (author). 16 refs., 13 tabs., 14 figs

  18. Improvement of visualization efficiency for the nondestructive inspection image of internal defects in plate type nuclear fuel

    International Nuclear Information System (INIS)

    Park, Seung Kyu; Park, Nak Kyu; Baik, Sung Hoon; Lee, Yoon Sang; Cheong, Yong Moo; Kang, Young June

    2012-01-01

    Plate type nuclear fuel has been adopted in most research reactors. The production quality of the fuel is a key part for an efficient and stable generation of thermal energy in research reactors. Thus, a nondestructive quality inspection for the internal defects of plate type nuclear fuel is a key process during the production of nuclear fuel for safety insurance. Nondestructive quality inspections based on X rays and ultrasounds have been widely used for the defect detection of plate type nuclear fuel. X ray testing is a simple and fast inspection method, and provides an image in real time as the inspection results. Thus, the testing can be carried out by a non expert field worker. However, it is hard to detect closed type defects that should be detected during the production of plate type nuclear fuel. Ultrasonic testing is a powerful tool to detect internal defects including open type and closed type defects in plate type nuclear fuel. However, the inspection process is complicated because an immersion test should be carried out in a water tank. It is also a time consuming inspection method because area testing to acquire image is based on the scanning of the point by point inspections. Among nondestructive inspection techniques, the techniques based on laser interferometry and infrared thermography have been widely used in the detection of internal defects of plate type composite materials, such as aircraft, automotive etc. While infrared thermography technique (IRT) analyses the thermal behavior of the specimen surface, laser interferometry technique (LIT) analyses the deformation field. Both techniques are useful tools for detection and evaluation of internal defects in composite materials. Especially, the laser interferometry technique can provide the depth information of internal defects. Laser interferometry technique (LIT) is a non contact inspection method faster than thermography. Also, this technique requires less energy than thermography and the

  19. High Efficiency Generation of Hydrogen Fuels Using Solar Thermochemical Splitting of Water

    Energy Technology Data Exchange (ETDEWEB)

    Heske, Clemens; Moujaes, Samir; Weimer, Alan; Wong, Bunsen; Siegal, Nathan; McFarland, Eric; Miller, Eric; Lewis, Michele; Bingham, Carl; Roth, Kurth; Sabacky, Bruce; Steinfeld, Aldo

    2011-09-29

    The objective of this work is to identify economically feasible concepts for the production of hydrogen from water using solar energy. The ultimate project objective was to select one or more competitive concepts for pilot-scale demonstration using concentrated solar energy. Results of pilot scale plant performance would be used as foundation for seeking public and private resources for full-scale plant development and testing. Economical success in this venture would afford the public with a renewable and limitless source of energy carrier for use in electric power load-leveling and as a carbon-free transportation fuel. The Solar Hydrogen Generation Research (SHGR) project embraces technologies relevant to hydrogen research under the Office of Hydrogen Fuel Cells and Infrastructure Technology (HFCIT) as well as concentrated solar power under the Office of Solar Energy Technologies (SET). Although the photoelectrochemical work is aligned with HFCIT, some of the technologies in this effort are also consistent with the skills and technologies found in concentrated solar power and photovoltaic technology under the Office of Solar Energy Technologies (SET). Hydrogen production by thermo-chemical water-splitting is a chemical process that accomplishes the decomposition of water into hydrogen and oxygen using only heat or a combination of heat and electrolysis instead of pure electrolysis and meets the goals for hydrogen production using only water and renewable solar energy as feed-stocks. Photoelectrochemical hydrogen production also meets these goals by implementing photo-electrolysis at the surface of a semiconductor in contact with an electrolyte with bias provided by a photovoltaic source. Here, water splitting is a photo-electrolytic process in which hydrogen is produced using only solar photons and water as feed-stocks. The thermochemical hydrogen task engendered formal collaborations among two universities, three national laboratories and two private sector

  20. Tungsten-rhenium composite tube fabricated by CVD for application in 18000C high thermal efficiency fuel processing furnace

    International Nuclear Information System (INIS)

    Svedberg, R.C.; Bowen, W.W.; Buckman, R.W. Jr.

    1980-04-01

    Chemical Vapor Deposit (CVD) rhenium was selected as the muffle material for an 1800 0 C high thermal efficiency fuel processing furnace. The muffle is exposed to high vacuum on the heater/insulation/instrumentation side and to a flowing argon-8 V/0 hydrogen gas mixture at one atmosphere pressure on the load volume side. During operation, the muffle cycles from room temperature to 1800 0 C and back to room temperature once every 24 hours. Operational life is dependent on resistance to thermal fatigue during the high temperature exposure. For a prototypical furnace, the muffle is approximately 13 cm I.D. and 40 cm in length. A small (about one-half size) rhenium closed end tube overcoated with tungsten was used to evaluate the concept. The fabrication and testing of the composite tungsten-rhenium tube and prototypic rhenium muffle is described

  1. Graphene-cobaltite-Pd hybrid materials for use as efficient bifunctional electrocatalysts in alkaline direct methanol fuel cells.

    Science.gov (United States)

    Sharma, Chandra Shekhar; Awasthi, Rahul; Singh, Ravindra Nath; Sinha, Akhoury Sudhir Kumar

    2013-12-14

    Hybrid materials comprising of Pd, MCo2O4 (where M = Mn, Co or Ni) and graphene have been prepared for use as efficient bifunctional electrocatalysts in alkaline direct methanol fuel cells. Structural and electrochemical characterizations were carried out using X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, chronoamperometry and cyclic, CO stripping, and linear sweep voltammetries. The study revealed that all the three hybrid materials are active for both methanol oxidation (MOR) and oxygen reduction (ORR) reactions in 1 M KOH. However, the Pd-MnCo2O4/GNS hybrid electrode exhibited the greatest MOR and ORR activities. This active hybrid electrode has also outstanding stability under both MOR and ORR conditions, while Pt- and other Pd-based catalysts undergo degradation under similar experimental conditions. The Pd-MnCo2O4/GNS hybrid catalyst exhibited superior ORR activity and stability compared to even Pt in alkaline solutions.

  2. Modern State and Efficiency Analysis of Heat Recovery in Fuel Furnaces Using High Temperature Recuperators. Part 2

    Directory of Open Access Journals (Sweden)

    B. S. Soroka

    2013-01-01

    Full Text Available The paper analyzes various factors that affect upon heat transfer in high temperature recuperators, namely: heat transfer enhancement, heat exchange surface increase and rise of temperature head between primary and secondary heat transfer fluids. Comparison of experimental data with the results of mathematical and computational fluid dynamics (CFD modeling has been performed in the paper. The paper considers some new designs of high temperature heat recovery plants: tube recuperator equipped with internal inserts – secondary emitters inside tubes for metallurgical furnaces and high-efficient two-way radiative recuperators for machinery engineering furnaces.  Advantages of new recuperators in comparison with existing analogues have been estimated in the paper. These advantages are:  provision of additional fuel saving due to increase of preheating temperature of the combustion air and improvement of design stability by decrease of tube wall temperature.

  3. Heating and Efficiency Comparison of a Fischer-Tropsch (FT) Fuel, JP-8+100, and Blends in a Three-Cup Combustor Sector

    Science.gov (United States)

    Thomas, Anna E.; Shouse, Dale T.; Neuroth, Craig; Lynch, Amy; Frayne, Charles W.; Stutrud, Jeffrey S.; Corporan, Edwin; Hankins, Terry; Saxena, Nikita T.; Hendricks, Robert C.

    2012-01-01

    In order to realize alternative fueling for military and commercial use, the industry has set forth guidelines that must be met by each fuel. These aviation fueling requirements are outlined in MIL-DTL-83133F(2008) or ASTM D 7566-Annex standards and are classified as drop-in fuel replacements. This paper provides combustor performance data for synthetic-paraffinic-kerosene- (SPK-) type (Fisher-Tropsch (FT)) fuel and blends with JP-8+100, relative to JP-8+100 as baseline fueling. Data were taken at various nominal inlet conditions: 75 psia (0.52 MPa) at 500 aF (533 K), 125 psia (0.86 MPa) at 625 aF (603 K), 175 psia (1.21 MPa) at 725 aF (658 K), and 225 psia (1.55 MPa) at 790 aF (694 K). Combustor performance analysis assessments were made for the change in flame temperatures, combustor efficiency, wall temperatures, and exhaust plane temperatures at 3%, 4%, and 5% combustor pressure drop (% P) for fuel:air ratios (F/A) ranging from 0.010 to 0.025. Significant general trends show lower liner temperatures and higher flame and combustor outlet temperatures with increases in FT fueling relative to JP-8+100 fueling. The latter affects both turbine efficiency and blade/vane life. In general, 100% SPK-FT fuel and blends with JP-8+100 produce less particulates and less smoke and have lower thermal impact on combustor hardware.

  4. An open circuit voltage equation enabling separation of cathode and anode polarization resistances of ceria electrolyte based solid oxide fuel cells

    Science.gov (United States)

    Zhang, Yanxiang; Chen, Yu; Yan, Mufu

    2017-07-01

    The open circuit voltage (OCV) of solid oxide fuel cells is generally overestimated by the Nernst equation and the Wagner equation, due to the polarization losses at electrodes. Considering both the electronic conduction of electrolyte and the electrode polarization losses, we express the OCV as an implicit function of the characteristic oxygen pressure of electrolyte (p* [atm], at which the electronic and ionic conductivities are the same), and the relative polarization resistance of electrodes (rc = Rc/Ri and ra = Ra/Ri, where Ri/c/a [Ωcm2] denotes the ionic resistance of electrolyte, and the polarization resistances of cathode and anode, respectively). This equation approaches to the Wagner equation when the electrodes are highly active (rc and ra → 0), and approaches to the Nernst equation when the electrolyte is a purely ionic conductor (p* → 0). For the fuel cells whose OCV is well below the prediction of the Wagner equation, for example with thin doped ceria electrolyte, it is demonstrated that the combination of OCV and impedance spectroscopy measurements allows the determination of p*, Rc and Ra. This equation can serve as a simple yet powerful tool to study the internal losses in the cell under open circuit condition.

  5. Control strategy for power management, efficiency-optimization and operating-safety of a 5-kW solid oxide fuel cell system

    International Nuclear Information System (INIS)

    Zhang, Lin; Jiang, Jianhua; Cheng, Huan; Deng, Zhonghua; Li, Xi

    2015-01-01

    Highlights: • Efficiency optimization associated with simultaneous power and thermal management. • Fast load tracing, fuel starvation, high efficiency and operating safety are considered. • Open loop pre-conditioning current strategy is proposed for load step-up transients. • Feedback control scheme is proposed for load step-up transients. - Abstract: The slow power tracking, operating safety, especially the fuel exhaustion, and high efficiency considerations are the key issues for integrated solid oxide fuel cell (SOFC) systems during power step up transients, resulting in the relatively poor dynamic capabilities and make the transient load following very challenging and must be enhanced. To this end, this paper first focus on addressing the efficiency optimization associated with simultaneous power and thermal management of a 5-kW SOFC system. Particularly, a traverse optimization process including cubic convolution interpolation algorithm are proposed to obtain optimal operating points (OOPs) with the maximum efficiency. Then this paper investigate the current implications on system step-up transient performance, then a two stage pre-conditioning current strategy and a feedback power reference control scheme is proposed for load step-up transients to balance fast load following and fuel starvation, after that safe thermal transient is validated. Simulation results show the efficacy of the control design by demonstrating the fast load following ability while maintaining the safe operation, thus safe; efficient and fast load transition can be achieved

  6. Methodical Approach to Estimation of Energy Efficiency Parameters of the Economy Under the Structural Changes in the Fuel And Energy Balance (on the Example of Baikal Region

    Directory of Open Access Journals (Sweden)

    Boris Grigorievich Saneev

    2013-12-01

    Full Text Available The authors consider a methodical approach which allows estimating energy efficiency parameters of the region’s economy using a fuel and energy balance (FEB. This approach was tested on the specific case of Baikal region. During the testing process the authors have developed ex ante and ex post FEBs and estimated energy efficiency parameters such as energy-, electro- and heat capacity of GRP, coefficients of useful utilization of fuel and energy resources and a monetary version of FEB. Forecast estimations are based on assumptions and limitations of technologically-intensive development scenario of the region. Authors show that the main factor of structural changes in the fuel and energy balance will be the large-scale development of hydrocarbon resources in Baikal region. It will cause structural changes in the composition of both the debit and credit of FEB (namely the structure of export and final consumption of fuel and energy resources. Authors assume that the forecast structural changes of the region’s FEB will significantly improve energy efficiency parameters of the economy: energy capacity of GRP will decrease by 1,5 times in 2010– 2030, electro and heat capacity – 1,9 times; coefficients of useful utilization of fuel and energy resources will increase by 3–5 p.p. This will save about 20 million tons of fuel equivalent (about 210 billion rubles in 2011 the prices until 2030

  7. Photoelectrochemical and electrocatalytic properties of thermally oxidized copper oxide for efficient solar fuel production

    KAUST Repository

    Garcia Esparza, Angel T.; Limkrailassiri, Kevin; Leroy, Fré dé ric; Rasul, Shahid; Yu, Weili; Lin, Liwei; Takanabe, Kazuhiro

    2014-01-01

    We report the use of a facile and highly scalable synthesis process to control growth products of earth-abundant Cu-based oxides and their application in relevant photoelectrochemical and electrochemical solar fuel generation systems. Characterization of the synthesized Cu(I)/Cu(II) oxides indicates that their surface morphology and chemical composition can be simply tuned by varying two synthesis parameters (time and temperature). UV-Vis spectroscopy and impedance spectroscopy studies are performed to estimate the band structures and electronic properties of these p-type semiconductor materials. Photoelectrodes made of Cu oxides possess favorable energy band structures for production of hydrogen from water; the position of their conduction band is ≈1 V more negative than the water-reduction potential. High acceptor concentrations on the order of 1018-1019 cm-3 are obtained, producing large electric fields at the semiconductor-electrolyte interface and thereby enhancing charge separation. The highly crystalline pristine samples used as photocathodes in photoelectrochemical cells exhibit high photocurrents under AM 1.5G simulated illumination. When the samples are electrochemically reduced under galvanostatic conditions, the co-existence of the oxide with metallic Cu on the surface seems to function as an effective catalyst for the selective electrochemical reduction of CO2. © the Partner Organisations 2014.

  8. Energy efficiency and fuel switching in Canadian industry under greenhouse gas regulation

    International Nuclear Information System (INIS)

    Margolick, M.

    1992-01-01

    The application of financial instruments to greenhouse gas control, particularly a greenhouse gas tax, is discussed. As of June 1991, Finland, the Netherlands, Sweden and Norway have imposed taxes on greenhouse gas emissions, while taxes are imminent in Denmark and Germany. A study has been carried out to model the effects of such taxes on greenhouse gas emissions in Canada, using the Intra-Sectoral Technology Use Model (ISTUM) and an end-use energy demand computer model. Only carbon dioxide and methane were considered. The limitations of the ISTUM model are discussed. Industry results are presented by sector, including an overview of greenhouse gas-producing processes, emission reduction measures possible, energy and greenhouse emissions, and results of taxes at varying levels. Different basic physical and chemical processes among industries would cause widely varying responses to a greenhouse gas tax. Issues which bear directly on greenhouse gas emissions include the burning of biomass fuels in the pulp and paper industry, strategic choices between existing and new technologies in the iron and steel sector, the possibility of a nearly greenhouse gas-free aluminum smelting sector, and the advent of reformulated gasoline requirements and declining crude oil quantity in the petroleum refining sector. 15 refs., 6 figs

  9. In situ formation of graphene layers on graphite surfaces for efficient anodes of microbial fuel cells.

    Science.gov (United States)

    Tang, Jiahuan; Chen, Shanshan; Yuan, Yong; Cai, Xixi; Zhou, Shungui

    2015-09-15

    Graphene can be used to improve the performance of the anode in a microbial fuel cell (MFC) due to its good biocompatibility, high electrical conductivity and large surface area. However, the chemical production and modification of the graphene on the anode are environmentally hazardous because of the use of various harmful chemicals. This study reports a novel method based on the electrochemical exfoliation of a graphite plate (GP) for the in situ formation of graphene layers on the surface of a graphite electrode. When the resultant graphene-layer-based graphite plate electrode (GL/GP) was used as an anode in an MFC, a maximum power density of 0.67 ± 0.034 W/m(2) was achieved. This value corresponds to 1.72-, 1.56- and 1.26-times the maximum power densities of the original GP, exfoliated-graphene-modified GP (EG/GP) and chemically-reduced-graphene-modified GP (rGO/GP) anodes, respectively. Electrochemical measurements revealed that the high performance of the GL/GP anode was attributable to its macroporous structure, improved electron transfer and high electrochemical capacitance. The results demonstrated that the proposed method is a facile and environmentally friendly synthesis technique for the fabrication of high-performance graphene-based electrodes for use in microbial energy harvesting. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Polymer Solar Cells with Efficiency >10% Enabled via a Facile Solution-Processed Al-Doped ZnO Electron Transporting Layer

    KAUST Repository

    Jagadamma, Lethy Krishnan; Al-Senani, Mohammed; El Labban, Abdulrahman; Gereige, Issam; Ngongang Ndjawa, Guy Olivier; Faria, Jorge C D; Kim, Taesoo; Zhao, Kui; Cruciani, Federico; Anjum, Dalaver H.; McLachlan, Martyn A.; Beaujuge, Pierre; Amassian, Aram

    2015-01-01

    /reduces the native defects by nitrogen incorporation, making them good electron transporters and energetically matched with the fullerene acceptor. It is demonstrated that highly efficient solar cells can be achieved without the need for additional surface chemical

  11. How High Local Charge Carrier Mobility and an Energy Cascade in a Three-Phase Bulk Heterojunction Enable >90% Quantum Efficiency

    KAUST Repository

    Burke, Timothy M.

    2013-12-27

    Charge generation in champion organic solar cells is highly efficient in spite of low bulk charge-carrier mobilities and short geminate-pair lifetimes. In this work, kinetic Monte Carlo simulations are used to understand efficient charge generation in terms of experimentally measured high local charge-carrier mobilities and energy cascades due to molecular mixing. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. How High Local Charge Carrier Mobility and an Energy Cascade in a Three-Phase Bulk Heterojunction Enable >90% Quantum Efficiency

    KAUST Repository

    Burke, Timothy M.; McGehee, Michael D.

    2013-01-01

    Charge generation in champion organic solar cells is highly efficient in spite of low bulk charge-carrier mobilities and short geminate-pair lifetimes. In this work, kinetic Monte Carlo simulations are used to understand efficient charge generation in terms of experimentally measured high local charge-carrier mobilities and energy cascades due to molecular mixing. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Remotex: a new concept for efficient remote operation and maintenance in nuclear fuel reprocessing

    International Nuclear Information System (INIS)

    Feldman, M.J.; White, J.R.

    1980-01-01

    Remotex is a concept of remote operation and maintenance that utilizes advanced manipulator design to improve plant operating efficiency, reduce personnel exposure, and improve safeguards and diversion resistance. It is a concept developed over the past two years in the conceptual design of the Hot Experimental Facility (HEF), a mechanically intense pilot plant facility designed to demonstrate reprocessng technology for early US breeder demonstration reactors. The Remotex concept is directly applicable to all segments of nuclear and nonnuclear industries where work tasks or conditions exist that are hazardous to the health of man

  14. Technology Options for Improved Air Vehicle Fuel Efficiency: Executive Summary and Annotated Brief

    Science.gov (United States)

    2006-05-01

    turbine cycle, and detonation-based engine cycles. Aerodynamic Solutions. In the near term, wing retrofits such as winglets have demonstrated the...Release 30 Public Release Aerodynamic Solutions: Benefits/Cost • Near term (0-5 years): ∆ FE ∆ FE/Cost • Wing retrofits, e.g., winglets 5% High • Mid...engine’s overall efficiency, ηo), by improved vehicle aerodynamic characteristics (e.g., through an increase in the lift-to-drag or L/D ratio), and

  15. Efficiency gain of solid oxide fuel cell systems by using anode offgas recycle - Results for a small scale propane driven unit

    Science.gov (United States)

    Dietrich, Ralph-Uwe; Oelze, Jana; Lindermeir, Andreas; Spitta, Christian; Steffen, Michael; Küster, Torben; Chen, Shaofei; Schlitzberger, Christian; Leithner, Reinhard

    The transfer of high electrical efficiencies of solid oxide fuel cells (SOFC) into praxis requires appropriate system concepts. One option is the anode-offgas recycling (AOGR) approach, which is based on the integration of waste heat using the principle of a chemical heat pump. The AOGR concept allows a combined steam- and dry-reforming of hydrocarbon fuel using the fuel cell products steam and carbon dioxide. SOFC fuel gas of higher quantity and quality results. In combination with internal reuse of waste heat the system efficiency increases compared to the usual path of partial oxidation (POX). The demonstration of the AOGR concept with a 300 Wel-SOFC stack running on propane required: a combined reformer/burner-reactor operating in POX (start-up) and AOGR modus; a hotgas-injector for anode-offgas recycling to the reformer; a dynamic process model; a multi-variable process controller; full system operation for experimental proof of the efficiency gain. Experimental results proof an efficiency gain of 18 percentage points (η·POX = 23%, η·AOGR = 41%) under idealized lab conditions. Nevertheless, further improvements of injector performance, stack fuel utilization and additional reduction of reformer reformer O/C ratio and system pressure drop are required to bring this approach into self-sustaining operation.

  16. Energy efficiency of multiport power converters used in plug-in/V2G fuel cell vehicles

    International Nuclear Information System (INIS)

    Bizon, Nicu

    2012-01-01

    Highlights: ► It is proposed a new FC hybrid power source topology for plug-in FC vehicle (PFCV). ► An energy efficiency analysis of three architectures for Multiport Power Converter (MPC) of HPS is performed. ► The MPC energy efficiency features were shown by analytical computing in all PFCV regimes. -- Abstract: In this paper is presented an analysis of energy efficiency for the Multiport Power Converters (MPCs) used in Plug-in Fuel Cell Vehicles (PFCVs). A generic MPC architecture for PFCVs is proposed, which is analyzed for different operating modes of MPC in relation with PFCV operating regimes and the plug-in feature. The basic MPC architecture is described in relation with the PFCV operating regimes. Two MPC architectures are derived from the basic MPC architecture: (1) the MPC1 architecture, which is the MPC architecture without reverse power flow during regenerative braking process, and (2) the MPC2 architecture – MPC architecture without charging mode of Energy Storage System (ESS) from the FC system. Taking in account the imposed window for the ESS state-of-charge, the MPC can be connected to Plug-in Charging Stations (PCS) to exchange power with the Electric Power (EP) system, which will include renewable Distributed Generation (DG) systems. The Energy Management Unit (EMU) of MPC can communicate with the EP system to determine the moments that match the energy demand of plug-in vehicle with the supply availability of the EP system, stabilizing the EP system. The MPC features regarding its energy efficiency were shown by analytical computing performed and appropriate simulations presented in relation with the ESS that can be charged (discharged) from (to) the home/DG/EP system.

  17. Effects of upgrading systems on energy conversion efficiency of a gasifier - fuel cell - gas turbine power plant

    International Nuclear Information System (INIS)

    Pedrazzi, Simone; Allesina, Giulio; Tartarini, Paolo

    2016-01-01

    Highlights: • An advanced gasifier-SOFC-MGT system is modeled. • An overall electrical efficiency of 32.81% is reached. • Influence of all the sub-system modeled on the power plant efficiency is discussed. • Compression storage of syngas is taken into account. - Abstract: This work focuses on a DG-SOFC-MGT (downdraft gasifier - solid oxide fuel cell - micro gas turbine) power plant for electrical energy production and investigates two possible performance-upgrading systems: polyphenylene oxide (PPO) membrane and zeolite filters. The first is used to produce oxygen-enriched air used in the reactor, while the latter separates the CO_2 content from the syngas. In order to prevent power plant shutdowns during the gasifier reactor scheduled maintenance, the system is equipped with a gas storage tank. The generation unit consists of a SOFC-MGT system characterized by higher electrical efficiency when compared to conventional power production technology (IC engines, ORC and EFGT). Poplar wood chips with 10% of total moisture are used as feedstock. Four different combinations with and without PPO and zeolite filtrations are simulated and discussed. One-year energy and power simulation were used as basis for comparison between all the cases analyzed. The modeling of the gasification reactions gives results consistent with literature about oxygen-enriched processes. Results showed that the highest electrical efficiency obtained is 32.81%. This value is reached by the power plant equipped only with PPO membrane filtration. Contrary to the PPO filtering, zeolite filtration does not increase the SOFC-MGT unit performance while it affects the energy balance with high auxiliary electrical consumption. This solution can be considered valuable only for future work coupling a CO_2 sequestration system to the power plant.

  18. Krakow clean fossil fuels and energy efficiency program. Phase 1 report

    Energy Technology Data Exchange (ETDEWEB)

    Butcher, T.; Pierce, B. [eds.

    1995-06-01

    Krakow is one of the largest and oldest cities in Poland. It is situated in the south of the country on the banks of the Vistula River. From the 11th until the 17th centuries, it was the capital of Poland. Today, Krakow is a city of 750,000 residents, one of the largest centers of higher education, an important industrial center, and is of particular importance because of the number and kinds of historic buildings and sites. For this reason, Krakow was included by the UNESCO in the list of the world`s cultural heritages. For about three decades, significant air pollution has been one of Krakow`s most serious problems. Because the city is situated in the Vistula River valley, it is poorly ventilated and experiences a high concentration of air pollutants. The quality of air in Krakow is affected mainly by industry (Sendzimir Steelworks, energy industry, chemical plants), influx from the Silesian industrial region (power plants, metallurgy), transboundary pollution (Ostrava - Czech Republic), and local sources of low pollution, i.e. more than 1,000 boiler houses using solid fuels and more than 100,000 coal-fired home stoves. These local sources, with low stacks and almost no pollution-control equipment, are responsible for about 35-40% of the air pollution. This report presents phase I results of a program to reduce pollution in krakow. Phase I was to gather information on emissions and costs, and to verify assumptions on existing heating methods and alternatives.

  19. Buried MoO x/Ag Electrode Enables High-Efficiency Organic/Silicon Heterojunction Solar Cells with a High Fill Factor.

    Science.gov (United States)

    Xia, Zhouhui; Gao, Peng; Sun, Teng; Wu, Haihua; Tan, Yeshu; Song, Tao; Lee, Shuit-Tong; Sun, Baoquan

    2018-04-25

    Silicon (Si)/organic heterojunction solar cells based on poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) and n-type Si have attracted wide interests because they promise cost-effectiveness and high-efficiency. However, the limited conductivity of PEDOT:PSS leads to an inefficient hole transport efficiency for the heterojunction device. Therefore, a high dense top-contact metal grid electrode is required to assure the efficient charge collection efficiency. Unfortunately, the large metal grid coverage ratio electrode would lead to undesirable optical loss. Here, we develop a strategy to balance PEDOT:PSS conductivity and grid optical transmittance via a buried molybdenum oxide/silver grid electrode. In addition, the grid electrode coverage ratio is optimized to reduce its light shading effect. The buried electrode dramatically reduces the device series resistance, which leads to a higher fill factor (FF). With the optimized buried electrode, a record FF of 80% is achieved for flat Si/PEDOT:PSS heterojunction devices. With further enhancement adhesion between the PEDOT:PSS film and Si substrate by a chemical cross-linkable silance, a power conversion efficiency of 16.3% for organic/textured Si heterojunction devices is achieved. Our results provide a path to overcome the inferior organic semiconductor property to enhance the organic/Si heterojunction solar cell.

  20. Improving efficiency of transport fuels production by thermal hydrolysis of waste activated sludge

    Science.gov (United States)

    Gulshin, Igor

    2017-10-01

    The article deals with issues of transport biofuels. Transport biofuels are an important element of a system of energy security. Moreover, as part of a system it is inextricably linked to the urban, rural or industrial infrastructure. The paper discusses methods of increasing the yield of biogas from anaerobic digesters at wastewater treatment plants. The thermal hydrolysis method was considered. The main advantages and drawbacks of this method were analyzed. The experimental biomass (from SNDOD-bioreactor) and high-organic substrate have been previously studied by respirometry methods. A biomethane potential of the investigated organic substrate has high rates because of substrate composition (the readily biodegradable substrate in the total composition takes about 85%). Waste activated sludge from SNDOD-bioreactor can be used for biofuel producing with high efficiency especially with pre-treatment like a thermal hydrolysis. Further studies have to consider the possibility of withdrawing inhibitors from waste activated sludge.

  1. Full 3D modelling of pulse propagation enables efficient nonlinear frequency conversion with low energy laser pulses in a single-element tripler

    Science.gov (United States)

    Kardaś, Tomasz M.; Nejbauer, Michał; Wnuk, Paweł; Resan, Bojan; Radzewicz, Czesław; Wasylczyk, Piotr

    2017-02-01

    Although new optical materials continue to open up access to more and more wavelength bands where femtosecond laser pulses can be generated, light frequency conversion techniques are still indispensable in filling the gaps on the ultrafast spectral scale. With high repetition rate, low pulse energy laser sources (oscillators) tight focusing is necessary for a robust wave mixing and the efficiency of broadband nonlinear conversion is limited by diffraction as well as spatial and temporal walk-off. Here we demonstrate a miniature third harmonic generator (tripler) with conversion efficiency exceeding 30%, producing 246 fs UV pulses via cascaded second order processes within a single laser beam focus. Designing this highly efficient and ultra compact frequency converter was made possible by full 3-dimentional modelling of propagation of tightly focused, broadband light fields in nonlinear and birefringent media.

  2. Pt and PtRu catalyst bilayers increase efficiencies for ethanol oxidation in proton exchange membrane electrolysis and fuel cells

    Science.gov (United States)

    Altarawneh, Rakan M.; Pickup, Peter G.

    2017-10-01

    Polarization curves, product distributions, and reaction stoichiometries have been measured for the oxidation of ethanol at anodes consisting of Pt and PtRu bilayers and a homogeneous mixture of the two catalysts. These anode structures all show synergies between the two catalysts that can be attributed to the oxidation of acetaldehyde produced at the PtRu catalyst by the Pt catalyst. The use of a PtRu layer over a Pt layer produces the strongest effect, with higher currents than a Pt on PtRu bilayer, mixed layer, or either catalyst alone, except for Pt at high potentials. Reaction stoichiometries (average number of electrons transferred per ethanol molecule) were closer to the values for Pt alone for both of the bilayer configurations but much lower for PtRu and mixed anodes. Although Pt alone would provide the highest overall fuel cell efficiency at low power densities, the PtRu on Pt bilayer would provide higher power densities without a significant loss of efficiency. The origin of the synergy between the Pt and PtRu catalysts was elucidated by separation of the total current into the individual components for generation of carbon dioxide and the acetaldehyde and acetic acid byproducts.

  3. High efficiency, quasi-instantaneous steam expansion device utilizing fossil or nuclear fuel as the heat source

    International Nuclear Information System (INIS)

    Claudio Filippone

    1999-01-01

    Thermal-hydraulic analysis of a specially designed steam expansion device (heat cavity) was performed to prove the feasibility of steam expansions at elevated rates for power generation with higher efficiency. The steam expansion process inside the heat cavity greatly depends on the gap within which the steam expands and accelerates. This system can be seen as a miniaturized boiler integrated inside the expander where steam (or the proper fluid) is generated almost instantaneously prior to its expansion in the work-producing unit. Relatively cold water is pulsed inside the heat cavity, where the heat transferred causes the water to flash to steam, thereby increasing its specific volume by a large factor. The gap inside the heat cavity forms a special nozzle-shaped system in which the fluid expands rapidly, accelerating toward the system outlet. The expansion phenomenon is the cause of ever-increasing fluid speed inside the cavity system, eliminating the need for moving parts (pumps, valves, etc.). In fact, the subsequent velocity induced by the sudden fluid expansion causes turbulent conditions, forcing accelerating Reynolds and Nusselt numbers which, in turn, increase the convective heat transfer coefficient. When the combustion of fossil fuels constitutes the heat source, the heat cavity concept can be applied directly inside the stator of conventional turbines, thereby greatly increasing the overall system efficiency

  4. Energy efficiency of conventional, organic, and alternative cropping systems for food and fuel at a site in the U.S. Midwest.

    Science.gov (United States)

    Gelfand, Ilya; Snapp, Sieglinde S; Robertson, G Philip

    2010-05-15

    The prospect of biofuel production on a large scale has focused attention on energy efficiencies associated with different agricultural systems and production goals. We used 17 years of detailed data on agricultural practices and yields to calculate an energy balance for different cropping systems under both food and fuel scenarios. We compared four grain and one forage systems in the U.S. Midwest: corn (Zea mays) - soybean (Glycine max) - wheat (Triticum aestivum) rotations managed with (1) conventional tillage, (2) no till, (3) low chemical input, and (4) biologically based (organic) practices, and (5) continuous alfalfa (Medicago sativa). We compared energy balances under two scenarios: all harvestable biomass used for food versus all harvestable biomass used for biofuel production. Among the annual grain crops, average energy costs of farming for the different systems ranged from 4.8 GJ ha(-1) y(-1) for the organic system to 7.1 GJ ha(-1) y(-1) for the conventional; the no-till system was also low at 4.9 GJ ha(-1) y(-1) and the low-chemical input system intermediate (5.2 GJ ha(-1) y(-1)). For each system, the average energy output for food was always greater than that for fuel. Overall energy efficiencies ranged from output:input ratios of 10 to 16 for conventional and no-till food production and from 7 to 11 for conventional and no-till fuel production, respectively. Alfalfa for fuel production had an efficiency similar to that of no-till grain production for fuel. Our analysis points to a more energetically efficient use of cropland for food than for fuel production and large differences in efficiencies attributable to management, which suggests multiple opportunities for improvement.

  5. AlGaAs-On-Insulator Nanowire with 750 nm FWM Bandwidth, -9 dB CW Conversion Efficiency, and Ultrafast Operation Enabling Record Tbaud Wavelength Conversion

    DEFF Research Database (Denmark)

    Pu, Minhao; Ottaviano, Luisa; Semenova, Elizaveta

    2015-01-01

    We present an AlGaAs-on-insulator platform for integrated nonlinear photonics. We demonstrate the highest reported conversion efficiency/length/pump-power, ultra-broadband fourwave mixing, and first-ever wavelength conversion of 1.28-Tbaud serial data signals in a 3-mm long dispersion-engineered AlGa...

  6. Polymer Solar Cells with Efficiency >10% Enabled via a Facile Solution-Processed Al-Doped ZnO Electron Transporting Layer

    KAUST Repository

    Jagadamma, Lethy Krishnan

    2015-04-22

    A facile and low-temperature (125 °C) solution-processed Al-doped ZnO (AZO) buffer layer functioning very effectively as electron accepting/hole blocking layer for a wide range of polymer:fullerene bulk heterojunction systems, yielding power conversion efficiency in excess of 10% (8%) on glass (plastic) substrates is described. The ammonia-treatment of the aqueous AZO nanoparticle solution produces compact, crystalline, and smooth thin films, which retain the aluminum doping, and eliminates/reduces the native defects by nitrogen incorporation, making them good electron transporters and energetically matched with the fullerene acceptor. It is demonstrated that highly efficient solar cells can be achieved without the need for additional surface chemical modifications of the buffer layer, which is a common requirement for many metal oxide buffer layers to yield efficient solar cells. Also highly efficient solar cells are achieved with thick AZO films (>50 nm), highlighting the suitability of this material for roll-to-roll coating. Preliminary results on the applicability of AZO as electron injection layer in F8BT-based polymer light emitting diode are also presented. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Study on fuel supplying method and methanol concentration sensor for the high efficient operation of methanol fuel cells. Methanol nenryo denchi no unten ni okeru nenryo kyokyu hoho no kento to methanol nodo sensor no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Tsukui, Tsutomu; Doi, Ryota; Yasukawa, Saburo; Kuroda, Osamu [Hirachi, Ltd., Tokyo, (Japan)

    1990-01-20

    A fuel supplying method was studied and demonstrated, essential to the high efficient operation of methanol fuel cells. Methanol and water were supplied independently from each tank to an anordic electrolyte tank in a circulating system, detecting a methanol concentration and liquid level of anordic electrolyte by each sensor, respectively. A methanol sensor was also developed to detect accurately the concentration based on electrochemical reaction under a constant voltage. A detection control circuit was insulated from a constant-voltage power supply to prevent external noises. The methanol sensor output was compensated for temperature, and a new level sensing method was adopted to send out a command comparing different responses to electrolyte shortage. As the methanol fuel cell was operated with this fuel supplying system, the stable characteristics of the cell were obtained within the variation of {plus minus} 0.1mol/l from the specified methanol concentration. 6 refs., 17 figs., 1 tab.

  8. Coupling molecular catalysts with nanostructured surfaces for efficient solar fuel production

    Science.gov (United States)

    Jin, Tong

    Solar fuel generation via carbon dioxide (CO2) reduction is a promising approach to meet the increasing global demand for energy and to minimize the impact of energy consumption on climate change. However, CO2 is thermodynamically stable; its activation often requires the use of appropriate catalysts. In particular, molecular catalysts with well-defined structures and tunability have shown excellent activity in photochemical CO2 reduction. These homogenous catalysts, however, suffer from poor stability under photochemical conditions and difficulty in recycling from the reaction media. Heterogenized molecular catalysts, particularly those prepared by coupling molecular catalysts with solid-state surfaces, have attracted more attention in recent years as potential solutions to address the issues associated with molecular catalysts. In this work, solar CO2 reduction is investigated using systems coupling molecular catalysts with robust nanostructured surfaces. In Chapter 2, heterogenization of macrocyclic cobalt(III) and nickel (II) complexes on mesoporous silica surface was achieved by different methods. Direct ligand derivatization significantly lowered the catalytic activity of Co(III) complex, while grafting the Co(III) complex onto silica surface through Si-O-Co linkage resulted in hybrid catalysts with excellent activity in CO2 reduction in the presence of p-terphenyl as a molecular photosensitizer. An interesting loading effect was observed, in which the optimal activity was achieved at a medium Co(III) surface density. Heterogenization of the Ni(II) complex on silica surface has also been implemented, the poor photocatalytic activity of the hybrid catalyst can be attributed to the intrinsic nature of the homogeneous analogue. This study highlighted the importance of appropriate linking strategies in preparing functional heterogenized molecular catalysts. Coupling molecular complexes with light-harvesting surfaces could avoid the use of expensive molecular

  9. Fuel processing

    International Nuclear Information System (INIS)

    Allardice, R.H.

    1990-01-01

    The technical and economic viability of the fast breeder reactor as an electricity generating system depends not only upon the reactor performance but also on a capability to recycle plutonium efficiently, reliably and economically through the reactor and fuel cycle facilities. Thus the fuel cycle is an integral and essential part of the system. Fuel cycle research and development has focused on demonstrating that the challenging technical requirements of processing plutonium fuel could be met and that the sometimes conflicting requirements of the fuel developer, fuel fabricator and fuel reprocessor could be reconciled. Pilot plant operation and development and design studies have established both the technical and economic feasibility of the fuel cycle but scope for further improvement exists through process intensification and flowsheet optimization. These objectives and the increasing processing demands made by the continuing improvement to fuel design and irradiation performance provide an incentive for continuing fuel cycle development work. (author)

  10. Upgrading of bio-oil to boiler fuel by catalytic hydrotreatment and esterification in an efficient process

    International Nuclear Information System (INIS)

    Zhang, Xinghua; Chen, Lungang; Kong, Wei; Wang, Tiejun; Zhang, Qi; Long, Jinxing; Xu, Ying; Ma, Longlong

    2015-01-01

    Bio-oil can't be directly used as fuel due to its deteriorate properties. Here, an efficient catalytic upgrading process for the bio-oil, including esterification, hydrogenation, hydrodeoxygenation and depolymerization, is proposed with multifunctional catalyst Ni/SiO 2 –ZrO 2 and biomass-derived solvent ethanol. Results showed that esters, alcohols, phenolics, and cyclo-ketones were the main components in the upgraded bio-oil while aldehydes were removed completely via catalytic hydrogenation and acids were removed by catalytic esterification with supercritical ethanol. The pH value of upgraded bio-oil rose drastically from 2.38 to 5.24, and the high heating value increased to 24.4 MJ kg −1 . Comparison characterization on the upgraded and crude bio-oil using FT-IR, GPC (Gel permeation chromatography) and 13 C NMR (Nuclear Magnetic Resonance) demonstrated that lignin-derived oligomers contained in crude bio-oil were further depolymerized over Ni/SiO 2 –ZrO 2 catalyst. The improved properties suggest that the upgraded bio-oil is more suitable to be used as boiler fuel. Furthermore, the loss of carbon is negligible because formation of coke is suppressed during the upgrading process. - Highlights: • Acid can be converted via catalytic esterification in supercritical ethanol. • Aldehydes can be removed completely during the upgrading process. • Lignin-derived oligomers were further depolymerized during the upgrading process. • Formation of coke is effectively inhibited during the upgrading process

  11. Development and Characterization of Fast Burning Solid Fuels/Propellants for Hybrid Rocket Motors with High Volumetric Efficiency

    Data.gov (United States)

    National Aeronautics and Space Administration — The objective of this proposed work is to develop several fast burning solid fuels/fuel-rich solid propellants for hybrid rocket motor applications. In the...

  12. A Lithium/Polysulfide Battery with Dual-Working Mode Enabled by Liquid Fuel and Acrylate-Based Gel Polymer Electrolyte.

    Science.gov (United States)

    Liu, Ming; Ren, Yuxun; Zhou, Dong; Jiang, Haoran; Kang, Feiyu; Zhao, Tianshou

    2017-01-25

    The low density associated with low sulfur areal loading in the solid-state sulfur cathode of current Li-S batteries is an issue hindering the development of this type of battery. Polysulfide catholyte as a recyclable liquid fuel was proven to enhance both the energy density and power density of the battery. However, a critical barrier with this lithium (Li)/polysulfide battery is that the shuttle effect, which is the crossover of polysulfides and side deposition on the Li anode, becomes much more severe than that in conventional Li-S batteries with a solid-state sulfur cathode. In this work, we successfully applied an acrylate-based gel polymer electrolyte (GPE) to the Li/polysulfide system. The GPE layer can effectively block the detrimental diffusion of polysulfides and protect the Li metal from the side passivation reaction. Cathode-static batteries utilizing 2 M catholyte (areal sulfur loading of 6.4 mg cm -2 ) present superior cycling stability (727.4 mAh g -1 after 500 cycles at 0.2 C) and high rate capability (814 mAh g -1 at 2 C) and power density (∼10 mW cm -2 ), which also possess replaceable and encapsulated merits for mobile devices. In the cathode-flow mode, the Li/polysulfide system with catholyte supplied from an external tank demonstrates further improved power density (∼69 mW cm -2 ) and stable cycling performance. This novel and simple Li/polysulfide system represents a significant advancement of high energy density sulfur-based batteries for future power sources.

  13. Biogas to syngas: flexible on-cell micro-reformer and NiSn bimetallic nanoparticle implanted solid oxide fuel cells for efficient energy conversion

    NARCIS (Netherlands)

    Hua, B.; Li, M.; Sun, Y.-F.; Zhang, Y.-Q.; Yan, N.; Chen, J.; Li, J.; Etsell, T.; Sarkar, P.; Luo, J.L.

    2016-01-01

    Solid oxide fuel cells (SOFCs) deliver an energy-efficient and eco-friendly pathway to convert biogas into syngas and electricity. However, many problems still need to be solved before their commercialization. Some of the disadvantages of biogas SOFC technology include coking and sulfur poisoning

  14. HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS USING NUCLEAR POWER FINAL RECHNICAL REPORT FOR THE PERIOD AUGUST 1, 1999 THROUGH SEPTEMBER 30, 2002 REV. 1

    Energy Technology Data Exchange (ETDEWEB)

    BROWN,LC; BESENBRUCH,GE; LENTSCH, RD; SCHULTZ,KR; FUNK,JF; PICKARD,PS; MARSHALL,AC; SHOWALTER,SK

    2003-12-01

    OAK-B135 Combustion of fossil fuels, used to power transportation, generate electricity, heat homes and fuel industry provides 86% of the world's energy [1-1,1-2]. Drawbacks to fossil fuel utilization include limited supply, pollution, and carbon dioxide emissions. Carbon dioxide emissions, thought to be responsible for global warming, are now the subject of international treaties [1-3,1-4]. Together, these drawbacks argue for the replacement of fossil fuels with a less-polluting potentially renewable primary energy such as nuclear energy. Conventional nuclear plants readily generate electric power but fossil fuels are firmly entrenched in the transportation sector. Hydrogen is an environmentally attractive transportation fuel that has the potential to displace fossil fuels. Hydrogen will be particularly advantageous when coupled with fuel cells. Fuel cells have higher efficiency than conventional battery/internal combustion engine combinations and do not produce nitrogen oxides during low-temperature operation. Contemporary hydrogen production is primarily based on fossil fuels and most specifically on natural gas. When hydrogen is produced using energy derived from fossil fuels, there is little or no environmental advantage. There is currently no large scale, cost-effective, environmentally attractive hydrogen production process available for commercialization, nor has such a process been identified. The objective of this work is to find an economically feasible process for the production of hydrogen, by nuclear means, using an advanced high-temperature nuclear reactor as the primary energy source. Hydrogen production by thermochemical water-splitting (Appendix A), a chemical process that accomplishes the decomposition of water into hydrogen and oxygen using only heat or, in the case of a hybrid thermochemical process, by a combination of heat and electrolysis, could meet these goals. Hydrogen produced from fossil fuels has trace contaminants (primarily

  15. Adaptation of H9N2 AIV in guinea pigs enables efficient transmission by direct contact and inefficient transmission by respiratory droplets

    Science.gov (United States)

    Sang, Xiaoyu; Wang, Airong; Ding, Jie; Kong, Huihui; Gao, Xiaolong; Li, Lin; Chai, Tongjie; Li, Yuanguo; Zhang, Kun; Wang, Chengyu; Wan, Zhonghai; Huang, Geng; Wang, Tiecheng; Feng, Na; Zheng, Xuexing; Wang, Hualei; Zhao, Yongkun; Yang, Songtao; Qian, Jun; Hu, Guixue; Gao, Yuwei; Xia, Xianzhu

    2015-01-01

    H9N2 avian influenza viruses circulate worldwide in poultry and have sporadically infected humans, raising concern whether H9N2 viruses have pandemic potential. Here, we use a guinea pig model to examine whether serial passage results in adaptive viral changes that confer a transmissible phenotype to a wild-type H9N2 virus. After nine serial passages of an H9N2 virus through guinea pigs, productive transmission by direct contact occurred in 2/3 guinea pig pairs. The efficiency of transmission by direct contact increased following the fifteenth passage and occurred in 3/3 guinea pig pairs. In contrast, airborne transmission of the passaged virus was less efficient and occurred in 1/6 guinea pig pairs and 0/6 ferret pairs after the fifteenth passage. Three amino acid substitutions, HA1-Q227P, HA2-D46E, and NP-E434K, were sufficient for contact transmission in guinea pigs (2/3 pairs). The two HA amino acid substitutions enhanced receptor binding to α2,3-linked sialic acid receptors. Additionally, the HA2-D46E substitution increased virus thermostability whereas the NP-E434K mutation enhanced viral RNA polymerase activity in vitro. Our findings suggest that adaptive changes that enhance viral receptor binding, thermostability, and replicative capacity in mammalian cells can collectively enhance the transmissibility of H9N2 AIVs by direct contact in the guinea pig model. PMID:26552719

  16. Facile and efficient room temperature solid state reaction enabled synthesis of antimony nanoparticles embedded within reduced graphene oxide for enhanced sodium-ion storage

    Science.gov (United States)

    Zhang, Xiukui; Wu, Ping; Jiang, Li; Zhang, Xiaofang; Shi, Hongxia; Zhu, Xiaoshu; Wei, Shaohua; Zhou, Yiming

    2018-06-01

    Herein, a very simple and cost-effective solid state reaction method is employed to obtain, for the first time, the antimony nanoparticles embedded within reduced graphene oxide matrices (designated as Sb/rGO). By directly grinding antimony chloride and sodium hydroxide together at room temperature in the presence of graphene oxide (GO), Sb4O5Cl2 precursor was quickly obtained, which is evenly incorporated in the graphene oxide matrices. After subsequent chemical reduction by NaBH4, the Sb/rGO composite was successfully synthesized. The as-prepared Sb/rGO composite consists of uniform Sb nanoparticles of sub-20 nm, all of which have been wrapped in and protected by the rGO matrices. The Sb nanoparticles serve as a sufficient sodium ion reservoir while the rGO matrices provide highly efficient pathways for transport of sodium ions and electrons. Moreover, the volume expansion of Sb during sodiation can be buffered in the rGO matrices. As a result, the Sb/rGO composite exhibits excellent electrochemical performance in sodium-ion batteries (SIBs), including an enhanced cycling stability with a highly reversible charge capacity of 455 mA h g-1 after 45 cycles at 100 mA g-1, and a coulombic efficiency exceeding 98% during cycling. The findings in the present work pave the way to not only synthesize the designated promising electrode materials for high performance SIBs, but also thoroughly understand the solid-state reaction.

  17. An Unfused-Core-Based Nonfullerene Acceptor Enables High-Efficiency Organic Solar Cells with Excellent Morphological Stability at High Temperatures.

    Science.gov (United States)

    Li, Shuixing; Zhan, Lingling; Liu, Feng; Ren, Jie; Shi, Minmin; Li, Chang-Zhi; Russell, Thomas P; Chen, Hongzheng

    2018-02-01

    Most nonfullerene acceptors developed so far for high-performance organic solar cells (OSCs) are designed in planar molecular geometry containing a fused-ring core. In this work, a new nonfullerene acceptor of DF-PCIC is synthesized with an unfused-ring core containing two cyclopentadithiophene (CPDT) moieties and one 2,5-difluorobenzene (DFB) group. A nearly planar geometry is realized through the F···H noncovalent interaction between CPDT and DFB for DF-PCIC. After proper optimizations, the OSCs with DF-PCIC as the acceptor and the polymer PBDB-T as the donor yield the best power conversion efficiency (PCE) of 10.14% with a high fill factor of 0.72. To the best of our knowledge, this efficiency is among the highest values for the OSCs with nonfullerene acceptors owning unfused-ring cores. Furthermore, no obvious morphological changes are observed for the thermally treated PBDB-T:DF-PCIC blended films, and the relevant devices can keep ≈70% of the original PCEs upon thermal treatment at 180 °C for 12 h. This tolerance of such a high temperature for so long time is rarely reported for fullerene-free OSCs, which might be due to the unique unfused-ring core of DF-PCIC. Therefore, the work provides new idea for the design of new nonfullerene acceptors applicable in commercial OSCs in the future. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Polymer solar cells with efficiency >10% enabled via a facile solution-processed Al-doped ZnO electron transporting layer

    KAUST Repository

    Jagadamma, Lethy Krishnan

    2015-10-05

    The present work details a facile and low-temperature (125C) solution-processed Al-doped ZnO (AZO) buffer layer functioning very effectively as electron accepting/hole blocking layer for a wide range of polymer:fullerene bulk heterojunction systems, and yielding power conversion efficiency in excess of 10% (8%) on glass (plastic) substrates. We show that ammonia addition to the aqueous AZO nanoparticle solution is a critically important step toward producing compact and smooth thin films which partially retain the aluminum doping and crystalline order of the starting AZO nanocrystals. The ammonia treatment appears to reduce the native defects via nitrogen incorporation, making the AZO film a very good electron transporter and energetically matched with the fullerene acceptor. Importantly, highly efficient solar cells are achieved without the need for additional surface chemical passivation or modification, which has become an increasingly common route to improving the performance of evaporated or solution-processed ZnO ETLs in solar cells.

  19. Lightweighting Automotive Materials for Increased Fuel Efficiency and Delivering Advanced Modeling and Simulation Capabilities to U.S. Manufacturers

    Energy Technology Data Exchange (ETDEWEB)

    Hale, Steve

    2013-09-11

    Abstract The National Center for Manufacturing Sciences (NCMS) worked with the U.S. Department of Energy (DOE), National Energy Technology Laboratory (NETL), to bring together research and development (R&D) collaborations to develop and accelerate the knowledgebase and infrastructure for lightweighting materials and manufacturing processes for their use in structural and applications in the automotive sector. The purpose/importance of this DOE program: • 2016 CAFÉ standards. • Automotive industry technology that shall adopt the insertion of lightweighting material concepts towards manufacturing of production vehicles. • Development and manufacture of advanced research tools for modeling and simulation (M&S) applications to reduce manufacturing and material costs. • U.S. competitiveness that will help drive the development and manufacture of the next generation of materials. NCMS established a focused portfolio of applied R&D projects utilizing lightweighting materials for manufacture into automotive structures and components. Areas that were targeted in this program: • Functionality of new lightweighting materials to meet present safety requirements. • Manufacturability using new lightweighting materials. • Cost reduction for the development and use of new lightweighting materials. The automotive industry’s future continuously evolves through innovation, and lightweight materials are key in achieving a new era of lighter, more efficient vehicles. Lightweight materials are among the technical advances needed to achieve fuel/energy efficiency and reduce carbon dioxide (CO2) emissions: • Establish design criteria methodology to identify the best materials for lightweighting. • Employ state-of-the-art design tools for optimum material development for their specific applications. • Match new manufacturing technology to production volume. • Address new process variability with new production-ready processes.

  20. Molecular and functional assessment of multicellular cancer spheroids produced in double emulsions enabled by efficient airway resistance based selective surface treatment

    Science.gov (United States)

    Ma, Xiao; Leth Jepsen, Morten; Ivarsen, Anne Kathrine R.; Knudsen, Birgitta R.; Ho, Yi-Ping

    2017-09-01

    Multicellular spheroids have garnered significant attention as an in vitro three-dimensional cancer model which can mimick the in vivo microenvironmental features. While microfluidics generated double emulsions have become a potential method to generate spheroids, challenges remain on the tedious procedures. Enabled by a novel ‘airway resistance’ based selective surface treatment, this study presents an easy and facile generation of double emulsions for the initiation and cultivation of multicellular spheroids in a scaffold-free format. Combining with our previously developed DNA nanosensors, intestinal spheroids produced in the double emulsions have shown an elevated activities of an essential DNA modifying enzyme, the topoisomerase I. The observed molecular and functional characteristics of spheroids produced in double emulsions are similar to the counterparts produced by the commercially available ultra-low attachment plates. However, the double emulsions excel for their improved uniformity, and the consistency of the results obtained by subsequent analysis of the spheroids. The presented technique is expected to ease the burden of producing spheroids and to promote the spheroids model for cancer or stem cell study.

  1. Efficient Production of N-Butyl Levulinate Fuel Additive from Levulinic Acid Using Amorphous Carbon Enriched with Oxygenated Groups

    Directory of Open Access Journals (Sweden)

    Jinfan Yang

    2018-01-01

    Full Text Available The aim of this study was to develop an effective carbonaceous solid acid for synthesizing green fuel additive through esterification of lignocellulose-derived levulinic acid (LA and n-butanol. Two different sulfonated carbons were prepared from glucose-derived amorphous carbon (GC400 and commercial active carbon (AC400. They were contrastively studied by a series of characterizations (N2 adsorption, X-ray diffraction, elemental analysis, transmission electron microscopy, Fourier transform infrared spectroscopy and NH3 temperature programmed desorption. The results indicated that GC400 possessed stronger acidity and higher –SO3H density than AC400, and the amorphous structure qualified GC400 for good swelling capacity in the reaction solution. Assessment experiments showed that GC400 displayed remarkably higher catalytic efficiency than AC400 and other typical solid acids (HZSM-5, Hβ, Amberlyst-15 and Nafion-212 resin. Up to 90.5% conversion of LA and 100% selectivity of n-butyl levulinate could be obtained on GC400 under the optimal reaction conditions. The sulfonated carbon retained 92% of its original catalytic activity even after five cycles.

  2. Simultaneous efficient removal of oxyfluorfen with electricity generation in a microbial fuel cell and its microbial community analysis.

    Science.gov (United States)

    Zhang, Qinghua; Zhang, Lei; Wang, Han; Jiang, Qinrui; Zhu, Xiaoyu

    2018-02-01

    The performance of a microbial fuel cell (MFC) to degrade oxyfluorfen was investigated. Approximately 77% of 50 mg/L oxyfluorfen was degraded within 24 h by anodic biofilm. The temperature, pH, and initial oxyfluorfen concentration had a significant effect on oxyfluorfen degrading, and a maximum degradation rate of 94.95% could theoretically be achieved at 31.96 °C, a pH of 7.65, and an initial oxyfluorfen concentration of 120.05 mg/L. Oxyfluorfen was further catabolized through various microbial metabolism pathways. Moreover, the anodic biofilm exhibited multiple catabolic capacities to 4-nitrophenol, chloramphenicol, pyraclostrobin, and sulfamethoxazole. Microbial community analysis indicated that functional bacteria Arcobacter, Acinetobacter, Azospirillum, Azonexus, and Comamonas were the predominant genera in the anodic biofilm. In terms of the efficient removal of various organic compounds and energy recovery, the MFC seemed to be a promising approach for the treatment of environmental contaminants. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. EUBIONET II. Efficient trading of biomass fuels and analysis of fuel supply chains and business models for market actors by networking. Final result-oriented report

    Energy Technology Data Exchange (ETDEWEB)

    Alakangas, E.; Wiik, C.; Vesterinen, P. (and others)

    2008-02-15

    The project aimed to increase deployment of biomass fuels into European market and match technology uptake by means of market and policy analysis and other well-defined tasks to meet European policy targets in renewable energy sector. The project is to result as increased use of biomass fuels and market uptake of innovative bioenergy technologies. The objectives of the project were the following: 1) To give a clear outlook on current and future biomass fuel market trends. 2) To give feedback on the suitability of CEN 335 biofuel standard for trading of solid biofuels. 3) To provide well-analysed estimation on techno-economic potential of the biomass fuel volumes until 2010 based on the existing studies and experts opinions. Regarding the forest biomass sector, co-operation will be done with forest industry stakeholders to find proper balance between forest industry raw material and bioenergy usage. 4) To enhance biomass fuel trade and technology transfer by networking among different actors. 5) To analyse, select and describe the most suitable trading and business models for small- and largescale biofuel supply chains for heat and power production by taking into account the environmental aspects and sustainability. 6) To enhance biomass usage by the means of co-operation and information dissemination among different market actors in the fuel-utilisation chain. Target groups were biomass fuel traders and users, fuel producers and suppliers of different scales, policy makers in both current and new member states. Key associations, i.e. AEBIOM and CEPI, were participating in the project and disseminating information to various groups. The project has been structured in 5 workpackages. Project was carried out by 16 partners, which are the key national bioenergy organisations in the European countries and have a long co-operation relationship in previous bioenergy networks. The project has published summary reports and national report of each WP and this report is

  4. Comparative economic efficiency, operating costs and fuel consumption rates of freight transport modes between the largest industrial cities and seaports in South Africa

    Directory of Open Access Journals (Sweden)

    W J (Wessel Pienaar

    2013-09-01

    Full Text Available The paper deals with aspects of efficiency within the five modes of freight transport, with special reference to the operating cost and fuel consumption rates between South Africa’s largest industrial cities and seaports. In particular, the paper deals with (a the opportunities that exist for the achievement of efficiency in freight transport; (b the subgroups of economies that can enhance efficiency attainment in the freight transport industry; (c prevailing cost structures, operating cost and fuel consumption rates within the five modes of freight transport; and (d the salient economic features of the freight transport market. The research approach and methodology combine (a a literature survey; (b empiric research, (c an analysis of the cost structures of freight transport operators from different modes of transport; and (d interviews conducted with specialists in the freight transport industry.

  5. Energy Conversion Alternatives Study (ECAS), Westinghouse phase 1. Volume 12: Fuel cells. [energy conversion efficiency of, for use in electric power plants

    Science.gov (United States)

    Warde, C. J.; Ruka, R. J.; Isenberg, A. O.

    1976-01-01

    A parametric assessment of four fuel cell power systems -- based on phosphoric acid, potassium hydroxide, molten carbonate, and stabilized zirconia -- has shown that the most important parameters for electricity-cost reduction and/or efficiency improvement standpoints are fuel cell useful life and power density, use of a waste-heat recovery system, and fuel type. Typical capital costs, overall energy efficiencies (based on the heating value of the coal used to produce the power plant fuel), and electricity costs are: phosphoric acid $350-450/kWe, 24-29%, and 11.7 to 13.9 mills/MJ (42 to 50 mills/kWh); alkaline $450-700/kWe, 26-31%, and 12.8 to 16.9 mills/MJ (46 to 61 mills/kWh); molten carbonate $480-650/kWe, 32-46%, and 10.6 to 19.4 mills/MJ (38 to 70 mills/kWh), stabilized zirconia $420-950/kWe, 26-53%, and 9.7 to 16.9 mills/MJ (35 to 61 mills/kWh). Three types of fuel cell power plants -- solid electrolytic with steam bottoming, molten carbonate with steam bottoming, and solid electrolyte with an integrated coal gasifier -- are recommended for further study.

  6. Effect of fuel oxygen on the energetic and exergetic efficiency of a compression ignition engine fuelled separately with palm and karanja biodiesels

    International Nuclear Information System (INIS)

    Jena, Jibanananda; Misra, Rahul Dev

    2014-01-01

    Exergy analysis of any thermodynamic system can take care of the limitations of energy analysis such as irreversible losses, their magnitude and the source of thermodynamic inefficiencies apart from energy losses. In the present study, both the analyses along with heat release analysis are conducted on a natural aspirated diesel engine fuelled separately with palm biodiesel (PB), karanja biodiesel (KB), and petrodiesel (PD) using the experimental data. Since the engine performs best at about 85% loading condition, the energetic and exergetic performance parameters of the engine are evaluated at 85% loading condition for each type of fuel. The aim of the study is to determine the effect of fuel oxygen on energy and exergy efficiencies of a CI (compression ignition) engine. Various exergy losses, exergy destruction and their ratios associated with the heat transfer through cooling water, radiation, exhaust gas, friction, and some uncounted exergy destruction are investigated. Apart from exergy loss due to heat transfer; the uncounted exergy destruction (due to combustion) also plays a major role in the system inefficiency. Based on the comparative assessment of the obtained results, it is concluded that a better combustion with less irreversibility is possible with the increase in O 2 content in the fuel. - Highlights: • Efficiency of a CI engine increases with the increase in oxygen quantity in the fuel. • Irreversibility of a CI engine decreases with increase in oxygen content in the fuel. • Palm biodiesel performs better than karanja biodiesel and petrodiesel for a CI engine

  7. A Diaminopropane-Appended Metal-Organic Framework Enabling Efficient CO2 Capture from Coal Flue Gas via a Mixed Adsorption Mechanism.

    Science.gov (United States)

    Milner, Phillip J; Siegelman, Rebecca L; Forse, Alexander C; Gonzalez, Miguel I; Runčevski, Tomče; Martell, Jeffrey D; Reimer, Jeffrey A; Long, Jeffrey R

    2017-09-27

    A new diamine-functionalized metal-organic framework comprised of 2,2-dimethyl-1,3-diaminopropane (dmpn) appended to the Mg 2+ sites lining the channels of Mg 2 (dobpdc) (dobpdc 4- = 4,4'-dioxidobiphenyl-3,3'-dicarboxylate) is characterized for the removal of CO 2 from the flue gas emissions of coal-fired power plants. Unique to members of this promising class of adsorbents, dmpn-Mg 2 (dobpdc) displays facile step-shaped adsorption of CO 2 from coal flue gas at 40 °C and near complete CO 2 desorption upon heating to 100 °C, enabling a high CO 2 working capacity (2.42 mmol/g, 9.1 wt %) with a modest 60 °C temperature swing. Evaluation of the thermodynamic parameters of adsorption for dmpn-Mg 2 (dobpdc) suggests that the narrow temperature swing of its CO 2 adsorption steps is due to the high magnitude of its differential enthalpy of adsorption (Δh ads = -73 ± 1 kJ/mol), with a larger than expected entropic penalty for CO 2 adsorption (Δs ads = -204 ± 4 J/mol·K) positioning the step in the optimal range for carbon capture from coal flue gas. In addition, thermogravimetric analysis and breakthrough experiments indicate that, in contrast to many adsorbents, dmpn-Mg 2 (dobpdc) captures CO 2 effectively in the presence of water and can be subjected to 1000 humid adsorption/desorption cycles with minimal degradation. Solid-state 13 C NMR spectra and single-crystal X-ray diffraction structures of the Zn analogue reveal that this material adsorbs CO 2 via formation of both ammonium carbamates and carbamic acid pairs, the latter of which are crystallographically verified for the first time in a porous material. Taken together, these properties render dmpn-Mg 2 (dobpdc) one of the most promising adsorbents for carbon capture applications.

  8. Coal gasification integration with solid oxide fuel cell and chemical looping combustion for high-efficiency power generation with inherent CO2 capture

    International Nuclear Information System (INIS)

    Chen, Shiyi; Lior, Noam; Xiang, Wenguo

    2015-01-01

    Highlights: • A novel power system integrating coal gasification with SOFC and chemical looping combustion. • The plant net power efficiency reaches 49.8% with complete CO 2 separation. • Energy and exergy analysis of the entire plant is conducted. • Sensitivity analysis shows a nearly constant power output when SOFC temperature and pressure vary. • NiO oxygen carrier shows higher plant efficiency than using Fe 2 O 3 and CuO. - Abstract: Since solid oxide fuel cells (SOFC) produce electricity with high energy conversion efficiency, and chemical looping combustion (CLC) is a process for fuel conversion with inherent CO 2 separation, a novel combined cycle integrating coal gasification, solid oxide fuel cell, and chemical looping combustion was configured and analyzed. A thermodynamic analysis based on energy and exergy was performed to investigate the performance of the integrated system and its sensitivity to major operating parameters. The major findings include that (1) the plant net power efficiency reaches 49.8% with ∼100% CO 2 capture for SOFC at 900 °C, 15 bar, fuel utilization factor = 0.85, fuel reactor temperature = 900 °C and air reactor temperature = 950 °C, using NiO as the oxygen carrier in the CLC unit. (2) In this parameter neighborhood the fuel utilization factor, the SOFC temperature and SOFC pressure have small effects on the plant net power efficiency because changes in pressure and temperature that increase the power generation by the SOFC tend to decrease the power generation by the gas turbine and steam cycle, and v.v.; an advantage of this system characteristic is that it maintains a nearly constant power output even when the temperature and pressure vary. (3) The largest exergy loss is in the gasification process, followed by those in the CO 2 compression and the SOFC. (4) Compared with the CLC Fe 2 O 3 and CuO oxygen carriers, NiO results in higher plant net power efficiency. To the authors’ knowledge, this is the first

  9. The Combinational Use of CRISPR/Cas9 and Targeted Toxin Technology Enables Efficient Isolation of Bi-Allelic Knockout Non-Human Mammalian Clones

    Directory of Open Access Journals (Sweden)

    Satoshi Watanabe

    2018-04-01

    Full Text Available Recent advances in genome editing systems such as clustered regularly interspaced short palindromic repeats/CRISPR-associated protein-9 nuclease (CRISPR/Cas9 have facilitated genomic modification in mammalian cells. However, most systems employ transient treatment with selective drugs such as puromycin to obtain the desired genome-edited cells, which often allows some untransfected cells to survive and decreases the efficiency of generating genome-edited cells. Here, we developed a novel targeted toxin-based drug-free selection system for the enrichment of genome-edited cells. Cells were transfected with three expression vectors, each of which carries a guide RNA (gRNA, humanized Cas9 (hCas9 gene, or Clostridium perfringens-derived endo-β-galactosidase C (EndoGalC gene. Once EndoGalC is expressed in a cell, it digests the cell-surface α-Gal epitope, which is specifically recognized by BS-I-B4 lectin (IB4. Three days after transfection, these cells were treated with cytotoxin saporin-conjugated IB4 (IB4SAP for 30 min at 37 °C prior to cultivation in a normal medium. Untransfected cells and those weakly expressing EndoGalC will die due to the internalization of saporin. Cells transiently expressing EndoGalC strongly survive, and some of these surviving clones are expected to be genome-edited bi-allelic knockout (KO clones due to their strong co-expression of gRNA and hCas9. When porcine α-1,3-galactosyltransferase gene, which can synthesize the α-Gal epitope, was attempted to be knocked out, 16.7% and 36.7% of the surviving clones were bi-allelic and mono-allelic knockout (KO cells, respectively, which was in contrast to the isolation of clones in the absence of IB4SAP treatment. Namely, 0% and 13.3% of the resulting clones were bi-allelic and mono-allelic KO cells, respectively. A similar tendency was seen when other target genes such as DiGeorge syndrome critical region gene 2 and transforming growth factor-β receptor type 1 gene were

  10. A Diaminopropane-Appended Metal–Organic Framework Enabling Efficient CO 2 Capture from Coal Flue Gas via a Mixed Adsorption Mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Milner, Phillip J.; Siegelman, Rebecca L.; Forse, Alexander C.; Gonzalez, Miguel I.; Runčevski, Tomče [Materials; Martell, Jeffrey D.; Reimer, Jeffrey A.; Long, Jeffrey R. [Materials

    2017-09-14

    A new diamine-functionalized metal–organic framework comprised of 2,2-dimethyl-1,3-diaminopropane (dmpn) appended to the Mg2+ sites lining the channels of Mg2(dobpdc) (dobpdc4– = 4,4'-dioxidobiphenyl-3,3'-dicarboxylate) is characterized for the removal of CO2 from the flue gas emissions of coal-fired power plants. Unique to members of this promising class of adsorbents, dmpn–Mg2(dobpdc) displays facile step-shaped adsorption of CO2 from coal flue gas at 40 °C and near complete CO2 desorption upon heating to 100 °C, enabling a high CO2 working capacity (2.42 mmol/g, 9.1 wt %) with a modest 60 °C temperature swing. Evaluation of the thermodynamic parameters of adsorption for dmpn–Mg2(dobpdc) suggests that the narrow temperature swing of its CO2 adsorption steps is due to the high magnitude of its differential enthalpy of adsorption (Δhads = -73 ± 1 kJ/mol), with a larger than expected entropic penalty for CO2 adsorption (Δsads = -204 ± 4 J/mol·K) positioning the step in the optimal range for carbon capture from coal flue gas. In addition, thermogravimetric analysis and breakthrough experiments indicate that, in contrast to many adsorbents, dmpn–Mg2(dobpdc) captures CO2 effectively in the presence of water and can be subjected to 1000 humid adsorption/desorption cycles with minimal degradation. Solid-state 13C NMR spectra and single-crystal X-ray diffraction structures of the Zn analogue reveal that this material adsorbs CO2 via formation of both ammonium carbamates and carbamic acid pairs, the latter of which are crystallographically verified for the first time in a porous material. Taken together, these properties render dmpn–Mg2(dobpdc) one of the most promising adsorbents for carbon capture applications.

  11. An Efficient Two-Objective Hybrid Local Search Algorithm for Solving the Fuel Consumption Vehicle Routing Problem

    OpenAIRE

    Rao, Weizhen; Liu, Feng; Wang, Shengbin

    2016-01-01

    The classical model of vehicle routing problem (VRP) generally minimizes either the total vehicle travelling distance or the total number of dispatched vehicles. Due to the increased importance of environmental sustainability, one variant of VRPs that minimizes the total vehicle fuel consumption has gained much attention. The resulting fuel consumption VRP (FCVRP) becomes increasingly important yet difficult. We present a mixed integer programming model for the FCVRP, and fuel consumption is ...

  12. BlueDetect: An iBeacon-Enabled Scheme for Accurate and Energy-Efficient Indoor-Outdoor Detection and Seamless Location-Based Service

    Directory of Open Access Journals (Sweden)

    Han Zou

    2016-02-01

    Full Text Available The location and contextual status (indoor or outdoor is fundamental and critical information for upper-layer applications, such as activity recognition and location-based services (LBS for individuals. In addition, optimizations of building management systems (BMS, such as the pre-cooling or heating process of the air-conditioning system according to the human traffic entering or exiting a building, can utilize the information, as well. The emerging mobile devices, which are equipped with various sensors, become a feasible and flexible platform to perform indoor-outdoor (IO detection. However, power-hungry sensors, such as GPS and WiFi, should be used with caution due to the constrained battery storage on mobile device. We propose BlueDetect: an accurate, fast response and energy-efficient scheme for IO detection and seamless LBS running on the mobile device based on the emerging low-power iBeacon technology. By leveraging the on-broad Bluetooth module and our proposed algorithms, BlueDetect provides a precise IO detection service that can turn on/off on-board power-hungry sensors smartly and automatically, optimize their performances and reduce the power consumption of mobile devices simultaneously. Moreover, seamless positioning and navigation services can be realized by it, especially in a semi-outdoor environment, which cannot be achieved by GPS or an indoor positioning system (IPS easily. We prototype BlueDetect on Android mobile devices and evaluate its performance comprehensively. The experimental results have validated the superiority of BlueDetect in terms of IO detection accuracy, localization accuracy and energy consumption.

  13. BlueDetect: An iBeacon-Enabled Scheme for Accurate and Energy-Efficient Indoor-Outdoor Detection and Seamless Location-Based Service.

    Science.gov (United States)

    Zou, Han; Jiang, Hao; Luo, Yiwen; Zhu, Jianjie; Lu, Xiaoxuan; Xie, Lihua

    2016-02-22

    The location and contextual status (indoor or outdoor) is fundamental and critical information for upper-layer applications, such as activity recognition and location-based services (LBS) for individuals. In addition, optimizations of building management systems (BMS), such as the pre-cooling or heating process of the air-conditioning system according to the human traffic entering or exiting a building, can utilize the information, as well. The emerging mobile devices, which are equipped with various sensors, become a feasible and flexible platform to perform indoor-outdoor (IO) detection. However, power-hungry sensors, such as GPS and WiFi, should be used with caution due to the constrained battery storage on mobile device. We propose BlueDetect: an accurate, fast response and energy-efficient scheme for IO detection and seamless LBS running on the mobile device based on the emerging low-power iBeacon technology. By leveraging the on-broad Bluetooth module and our proposed algorithms, BlueDetect provides a precise IO detection service that can turn on/off on-board power-hungry sensors smartly and automatically, optimize their performances and reduce the power consumption of mobile devices simultaneously. Moreover, seamless positioning and navigation services can be realized by it, especially in a semi-outdoor environment, which cannot be achieved by GPS or an indoor positioning system (IPS) easily. We prototype BlueDetect on Android mobile devices and evaluate its performance comprehensively. The experimental results have validated the superiority of BlueDetect in terms of IO detection accuracy, localization accuracy and energy consumption.

  14. Use of short interfering RNA delivered by cationic liposomes to enable efficient down-regulation of PTPN22 gene in human T lymphocytes.

    Directory of Open Access Journals (Sweden)

    Valentina Perri

    Full Text Available Type 1 diabetes and thyroid disease are T cell-dependent autoimmune endocrinopathies. The standard substitutive administration of the deficient hormones does not halt the autoimmune process; therefore, development of immunotherapies aiming to preserve the residual hormonal cells, is of crucial importance. PTPN22 C1858T mutation encoding for the R620W lymphoid tyrosine phosphatase variant, plays a potential pathophysiological role in autoimmunity. The PTPN22 encoded protein Lyp is a negative regulator of T cell antigen receptor signaling; R620W variant, leading to a gain of function with paradoxical reduced T cell activation, may represent a valid therapeutic target. We aimed to develop novel wild type PTPN22 short interfering RNA duplexes (siRNA and optimize their delivery into Jurkat T cells and PBMC by using liposomal carriers. Conformational stability, size and polydispersion of siRNA in lipoplexes was measured by CD spectroscopy and DLS. Lipoplexes internalization and toxicity evaluation was assessed by confocal microscopy and flow cytometry analysis. Their effect on Lyp expression was evaluated by means of Western Blot and confocal microscopy. Functional assays through engagement of TCR signaling were established to evaluate biological consequences of down-modulation. Both Jurkat T cells and PBMC were efficiently transfected by stable custom lipoplexes. Jurkat T cell morphology and proliferation was not affected. Lipoplexes incorporation was visualized in CD3+ but also in CD3- peripheral blood immunotypes without signs of toxicity, damage or apoptosis. Efficacy in affecting Lyp protein expression was demonstrated in both transfected Jurkat T cells and PBMC. Moreover, impairment of Lyp inhibitory activity was revealed by increase of IL-2 secretion in culture supernatants of PBMC following anti-CD3/CD28 T cell receptor-driven stimulation. The results of our study open the pathway to future trials for the treatment of autoimmune diseases based

  15. Better and more efficient care through ICT-enabled integration of social care and healthcare services: experiences from two European projects

    Science.gov (United States)

    Müller, Sonja; Meyer, Ingo; Kubitschke, Lutz; Delaney, Sarah

    2012-01-01

    Unsynchronised social and health care service delivery leads to inefficiencies, duplication of resources and reduced levels of quality of care. Older people are particularly affected by this situation. They often need both types of services, such as support with daily living activities and chronic disease management. ICT has the potential to support integrated service delivery to achieve high quality independent living and wellbeing for older people across Europe and elsewhere. Against this background, the presentation will demonstrate experiences and results derived from the development and piloting of ICT-supported integrated care services in eight sites across Europe, namely Dublin, Hull, Milton Keynes, Malaga, Veldhoven, Geldrop, Eindhoven and Bielefeld. Through innovative usage of ICT, current ‘silos’ in service delivery are broken up to allow for cooperation across relevant care sectors and participation of family members. The integrated services are to support the effective management of chronic diseases, and to address issues which affect independence, such as reduced agility, vision or hearing, in order to significantly improve the quality of life for older people and their carers. A dedicated programme of service process innovation complemented by adaptation of technology is being pursued in order to develop an integrated digital support infrastructure and related services: using appropriate existing technology to provide as many older people as possible with digital access to support services they needaugmenting and opening sectoral care platforms to enable coordinated cross-sector support deliveryadopting a clearly demand-driven inclusive approach and avoiding a technology ‘push’. Wider deployment of the services is supported by a dedicated programme of socio-economic service evaluation. The evaluation framework utilises a multi-method and multi-perspective approach, involving end users, family carers, service provider staff and key informants

  16. Fuel efficiency of the Austrian passenger vehicle fleet-Analysis of trends in the technological profile and related impacts on CO2 emissions

    International Nuclear Information System (INIS)

    Meyer, I.; Wessely, S.

    2009-01-01

    This paper analyzes trends in the technological profile of the Austrian personnel vehicle fleet from 1990 to 2007. This includes the parameters of power, engine size and weight, which beyond the technological efficiency of the motor engine itself, are considered to be the main determinants of the fuel efficiency of the average car stock. Investigating the drivers of ever rising transport related greenhouse gas emissions is crucial in order to derive policies that strive towards more energy-efficient on-road passenger mobility. We focus on the efficacy of technological efficiency improvements in mitigating climate-relevant emissions from car use in light of shifting demand patterns towards bigger, heavier and more powerful cars. The analysis is descriptive in nature and based on a bottom-up database that was originally collated for the purpose of the present study. Technological data on car models, which includes tested fuel consumption, engine size, power and weight, is related to registered car stock and, in parts, to newly registered cars. From this, we obtain an original database of the Austrian passenger car fleet, i.e. information on consumer choice of specific car models, segregated by gasoline and diesel fuelled engines. Conclusions are derived for policies aimed at reducing the fossil fuel consumption of the moving vehicle fleet in order to contribute to a low carbon society.

  17. PAC-Car I - A highly efficient vehicle with hydrogen fuel cell; PAC-Car I - Vehicule ultra efficient a pile a combustible

    Energy Technology Data Exchange (ETDEWEB)

    Guzzella, L.; Paganelli, G. [Swiss Federal Institute of Technology (EPFZ), Institut fuer Mess- und Regeltechnik, ETH Zentrum, Zuerich (Switzerland); Santin, J.-J. [UVHC - Campus du Mont Houy, Valenciennes (France)

    2003-07-01

    This report presents a very low energy consumption vehicle developed for the 2003 edition of the Shell Eco-marathon race. Innovating developments were needed for most of its components, which are not yet available on the market. The chemical energy of hydrogen gas is first converted into electrical energy by a 900 W Proton Exchange Membrane Fuel Cell (PEMFC). The car is driven by two DC powered electrical motors, which get their energy from a power electronic converter supplied by the fuel cell. Hydrogen is stored as metal hydride, in the solid state. The report gives a detailed description of the fuel cell, the control system principles as well as a presentation of the hydrogen tank. Various pictures show the vehicle and some of its mechanical details. Performance monitoring indicated a fuel consumption of only 15.9 grams of hydrogen per 100 km; this corresponds to an equivalent of 1694 km for the consumption of one litre of lead-free 95 gasoline in a usual internal combustion engine. However, as the vehicle used for the race had not been specifically developed for the fuel cell based equipment and the research efforts were focused on the advanced propulsion systems, the overall performance could still be significantly improved by optimising the vehicle itself.

  18. Efficiency measurement and uncertainty discussion of an electric engine powered by a ``self-breathing'' and ``self-humidified'' proton exchange membrane fuel cell

    Science.gov (United States)

    Schiavetti, Pierluigi; Del Prete, Zaccaria

    2007-08-01

    The efficiency of an automotive engine based on a "self-breathing" and "self-humidified" proton exchange membrane fuel cell stack (PEM FC) connected to a dc brushless electrical motor was measured under variable power load conditions. Experiments have been carried out on a small scale 150W engine model. After determining the fuel cell static polarization curve and the time response to power steps, the system was driven to copy on the test bench a "standard urban load cycle" and its instantaneous efficiencies were measured at an acquisition rate of 5Hz. The integral system efficiency over the entire urban load cycle, comprising the losses of the unavoidable auxiliary components of the engine, was then calculated. The fuel cell stack was operated mainly in "partial" dead-end mode, with a periodic anode flow channel purging, and one test was carried out in "pure" dead-end mode, with no anode channel purging. An uncertainty analysis of the efficiencies was carried out, taking into account either type A and type B evaluation methods, strengthening the discussion about the outcomes obtained for a system based on this novel simplified FC type. For our small scale engine we measured over the standard urban cycle, on the basis of the H2 high heating value (HHV), a tank-to-wheel integral efficiency of (18.2±0.8)%, when the fuel cell was operated with periodic flow channel purging, and of (21.5±1.3)% in complete dead-end operation mode.

  19. A Wide Band Gap Polymer with a Deep Highest Occupied Molecular Orbital Level Enables 14.2% Efficiency in Polymer Solar Cells.

    Science.gov (United States)

    Li, Sunsun; Ye, Long; Zhao, Wenchao; Yan, Hongping; Yang, Bei; Liu, Delong; Li, Wanning; Ade, Harald; Hou, Jianhui

    2018-05-21

    To simultaneously achieve low photon energy loss ( E loss ) and broad spectral response, the molecular design of the wide band gap (WBG) donor polymer with a deep HOMO level is of critical importance in fullerene-free polymer solar cells (PSCs). Herein, we developed a new benzodithiophene unit, i.e., DTBDT-EF, and conducted systematic investigations on a WBG DTBDT-EF-based donor polymer, namely, PDTB-EF-T. Due to the synergistic electron-withdrawing effect of the fluorine atom and ester group, PDTB-EF-T exhibits a higher oxidation potential, i.e., a deeper HOMO level (ca. -5.5 eV) than most well-known donor polymers. Hence, a high open-circuit voltage of 0.90 V was obtained when paired with a fluorinated small molecule acceptor (IT-4F), corresponding to a low E loss of 0.62 eV. Furthermore, side-chain engineering demonstrated that subtle side-chain modulation of the ester greatly influences the aggregation effects and molecular packing of polymer PDTB-EF-T. With the benefits of the stronger interchain π-π interaction, the improved ordering structure, and thus the highest hole mobility, the most symmetric charge transport and reduced recombination are achieved for the linear decyl-substituted PDTB-EF-T (P2)-based PSCs, leading to the highest short-circuit current density and fill factor (FF). Due to the high Flory-Huggins interaction parameter (χ), surface-directed phase separation occurs in the P2:IT-4F blend, which is supported by X-ray photoemission spectroscopy results and cross-sectional transmission electron microscope images. By taking advantage of the vertical phase distribution of the P2:IT-4F blend, a high power conversion efficiency (PCE) of 14.2% with an outstanding FF of 0.76 was recorded for inverted devices. These results demonstrate the great potential of the DTBDT-EF unit for future organic photovoltaic applications.

  20. Analysis of the system efficiency of an intermediate temperature proton exchange membrane fuel cell at elevated temperature and relative humidity conditions

    International Nuclear Information System (INIS)

    Jeon, Seung Won; Cha, Dowon; Kim, Hyung Soon; Kim, Yongchan

    2016-01-01

    Highlights: • System efficiency of PEMFC is evaluated at elevated temperature and humidity. • Operating parameters are optimized using response surface methodology. • The optimal operating parameters are T = 90.6 °C, RH = 100.0%, and ζ = 2.07. • The power output and system efficiency are 1.28 W and 15.8% at the optimum. • The system efficiency can be effectively improved by increasing relative humidity. - Abstract: Humidification of the membrane is very important in a proton exchange membrane fuel cell (PEMFC), to maintain high ionic conductivity. At an elevated temperature, a large amount of thermal energy is required for humidification because of the exponentially increased saturation vapor pressure. In this study, the system efficiency of a PEMFC was evaluated by considering the heat required for preheating/humidification and compression work. Three-dimensional steady-state simulations were conducted using Fluent 14 to simulate the electrochemical reactions. The operating conditions were optimized using response surface methodology by considering both the fuel cell output and system efficiency. In addition, the effects of operating parameters such as the temperature, relative humidity, and stoichiometric ratio were investigated. The system efficiency can be improved more effectively by increasing relative humidity rather than increasing operating temperature because the ionic conductivity of the membrane was strongly influenced by the relative humidity.

  1. LPG a clean and efficient motor fuel: regulated and non-regulated emissions of a commercial attractive LPG vehicle

    NARCIS (Netherlands)

    Hollemans, B.H.

    1996-01-01

    Excise and other duties measures in Europe, threaten to affect the low price of LPG as a car fuel. As a result, this less polluting fuel would lose position. For this reason the Netherlands LPG industry commissioned TNO to undertake a study which would clearly demonstrate the advantages of LPG. The

  2. Influence of Climatic Factors on the Efficiency of Disposal Metal- Hydride Unit for the Double-Fuel Low-Speed Internal Combustion Engine of Gas Tankers

    OpenAIRE

    Cherednichenko, Oleksandr Costyntunovich; Tkach, Mykhaylo Romanovich

    2017-01-01

    Contemporary tendencies in the development of ship power engineering have been analyzed. Consideration was given to the specific features of the transportation of liquefied natural gas by gas tankers. The prospects of utilization of the secondary energy resources of marine double-fuel low-speed diesel engines were defined. The metal hydride units of a continuous action were offered for this purpose. The need for the estimation of the influence of climatic factors on the efficiency of disposal...

  3. Multi-objective design and operation of Solid Oxide Fuel Cell (SOFC) Triple Combined-cycle Power Generation systems: Integrating energy efficiency and operational safety

    International Nuclear Information System (INIS)

    Sharifzadeh, Mahdi; Meghdari, Mojtaba; Rashtchian, Davood

    2017-01-01

    Highlights: • Integrating Solid Oxide Fuel Cells with thermal power plants enhance overall energy efficiency. • However, the high degree of process integration in hybrid power plants limits the operating window. • Multi-objective optimization was applied for integrated design and operation. • The Pareto optimal solutions demonstrated strong trade-off between energy efficiency and operational safety. - Abstract: Energy efficiency is one of the main pathways for energy security and environmental protection. In fact, the International Energy Agency asserts that without energy efficiency, 70% of targeted emission reductions are not achievable. Despite this clarity, enhancing the energy efficiency introduce significant challenge toward process operation. The reason is that the methods applied for energy-saving pose the process operation at the intersection of safety constraints. The present research aims at uncovering the trade-off between safe operation and energy efficiency; an optimization framework is developed that ensures process safety and simultaneously optimizes energy-efficiency, quantified in economic terms. The developed optimization framework is demonstrated for a solid oxide fuel cell (SOFC) power generation system. The significance of this industrial application is that SOFC power plants apply a highly degree of process integration resulting in very narrow operating windows. However, they are subject to significant uncertainties in power demand. The results demonstrate a strong trade-off between the competing objectives. It was observed that highly energy-efficient designs feature a very narrow operating window and limited flexibility. For instance, expanding the safe operating window by 100% will incur almost 47% more annualized costs. Establishing such a trade-off is essential for realizing energy-saving.

  4. Achieving clean and efficient engine operation up to full load by combining optimized RCCI and dual-fuel diesel-gasoline combustion strategies

    International Nuclear Information System (INIS)

    Benajes, Jesús; García, Antonio; Monsalve-Serrano, Javier; Boronat, Vicente

    2017-01-01

    Highlights: • Optimized dual-fuel strategy to cover the whole engine load-speed map. • EURO VI NOx levels up to 14 bar IMEP with fully and highly premixed RCCI strategies. • Dual-fuel provides up to 7% higher efficiency than CDC if urea consumption is considered. - Abstract: This experimental work investigates the capabilities of the reactivity controlled compression ignition combustion concept to be operated in the whole engine map and discusses its benefits when compared to conventional diesel combustion. The experiments were conducted using a single-cylinder medium-duty diesel engine fueled with regular gasoline and diesel fuels. The main modification on the stock engine architecture was the addition of a port fuel injector in the intake manifold. In addition, with the aim of extending the reactivity controlled compression ignition operating range towards higher loads, the piston bowl volume was increased to reduce the compression ratio of the engine from 17.5:1 (stock) down to 15.3:1. To allow the dual-fuel operation over the whole engine map without exceeding the mechanical limitations of the engine, an optimized dual-fuel combustion strategy is proposed in this research. The combustion strategy changes as the engine load increases, starting from a fully premixed reactivity controlled compression ignition combustion up to around 8 bar IMEP, then switching to a highly premixed reactivity controlled compression ignition combustion up to 15 bar IMEP, and finally moving to a mainly diffusive dual-fuel combustion to reach the full load operation. The engine mapping results obtained using this combustion strategy show that reactivity controlled compression ignition combustion allows fulfilling the EURO VI NOx limit up to 14 bar IMEP. Ultra-low soot emissions are also achieved when the fully premixed combustion is promoted, however, the soot levels rise notably as the combustion strategy moves to a less premixed pattern. Finally, the direct comparison of

  5. Energy efficiency : potential fuel savings generated by a national speed limit would be influenced by many other factors.

    Science.gov (United States)

    2008-11-07

    "Congress expressed interest in obtaining information on using a national speed limit to reduce fuel consumption. In response to the request, we reviewed existing literature and consulted knowledgeable stakeholders on the following: (1) What is the r...

  6. Nuclear fuels

    International Nuclear Information System (INIS)

    Beauvy, M.; Berthoud, G.; Defranceschi, M.; Ducros, G.; Guerin, Y.; Limoge, Y.; Madic, Ch.; Santarini, G.; Seiler, J.M.; Sollogoub, P.; Vernaz, E.; Guillet, J.L.; Ballagny, A.; Bechade, J.L.; Bonin, B.; Brachet, J.Ch.; Delpech, M.; Dubois, S.; Ferry, C.; Freyss, M.; Gilbon, D.; Grouiller, J.P.; Iracane, D.; Lansiart, S.; Lemoine, P.; Lenain, R.; Marsault, Ph.; Michel, B.; Noirot, J.; Parrat, D.; Pelletier, M.; Perrais, Ch.; Phelip, M.; Pillon, S.; Poinssot, Ch.; Vallory, J.; Valot, C.; Pradel, Ph.; Bonin, B.; Bouquin, B.; Dozol, M.; Lecomte, M.; Vallee, A.; Bazile, F.; Parisot, J.F.; Finot, P.; Roberts, J.F.

    2009-01-01

    Fuel is one of the essential components in a reactor. It is within that fuel that nuclear reactions take place, i.e. fission of heavy atoms, uranium and plutonium. Fuel is at the core of the reactor, but equally at the core of the nuclear system as a whole. Fuel design and properties influence reactor behavior, performance, and safety. Even though it only accounts for a small part of the cost per kilowatt-hour of power provided by current nuclear power plants, good utilization of fuel is a major economic issue. Major advances have yet to be achieved, to ensure longer in-reactor dwell-time, thus enabling fuel to yield more energy; and improve ruggedness. Aside from economics, and safety, such strategic issues as use of plutonium, conservation of resources, and nuclear waste management have to be addressed, and true technological challenges arise. This Monograph surveys current knowledge regarding in-reactor behavior, operating limits, and avenues for R and D. It also provides illustrations of ongoing research work, setting out a few noteworthy results recently achieved. Content: 1 - Introduction; 2 - Water reactor fuel: What are the features of water reactor fuel? 9 (What is the purpose of a nuclear fuel?, Ceramic fuel, Fuel rods, PWR fuel assemblies, BWR fuel assemblies); Fabrication of water reactor fuels (Fabrication of UO 2 pellets, Fabrication of MOX (mixed uranium-plutonium oxide) pellets, Fabrication of claddings); In-reactor behavior of UO 2 and MOX fuels (Irradiation conditions during nominal operation, Heat generation, and removal, The processes involved at the start of irradiation, Fission gas behavior, Microstructural changes); Water reactor fuel behavior in loss of tightness conditions (Cladding, the first containment barrier, Causes of failure, Consequences of a failure); Microscopic morphology of fuel ceramic and its evolution under irradiation; Migration and localization of fission products in UOX and MOX matrices (The ceramic under irradiation

  7. Nuclear fuels

    Energy Technology Data Exchange (ETDEWEB)

    Beauvy, M.; Berthoud, G.; Defranceschi, M.; Ducros, G.; Guerin, Y.; Limoge, Y.; Madic, Ch.; Santarini, G.; Seiler, J.M.; Sollogoub, P.; Vernaz, E.; Guillet, J.L.; Ballagny, A.; Bechade, J.L.; Bonin, B.; Brachet, J.Ch.; Delpech, M.; Dubois, S.; Ferry, C.; Freyss, M.; Gilbon, D.; Grouiller, J.P.; Iracane, D.; Lansiart, S.; Lemoine, P.; Lenain, R.; Marsault, Ph.; Michel, B.; Noirot, J.; Parrat, D.; Pelletier, M.; Perrais, Ch.; Phelip, M.; Pillon, S.; Poinssot, Ch.; Vallory, J.; Valot, C.; Pradel, Ph.; Bonin, B.; Bouquin, B.; Dozol, M.; Lecomte, M.; Vallee, A.; Bazile, F.; Parisot, J.F.; Finot, P.; Roberts, J.F

    2009-07-01

    Fuel is one of the essential components in a reactor. It is within that fuel that nuclear reactions take place, i.e. fission of heavy atoms, uranium and plutonium. Fuel is at the core of the reactor, but equally at the core of the nuclear system as a whole. Fuel design and properties influence reactor behavior, performance, and safety. Even though it only accounts for a small part of the cost per kilowatt-hour of power provided by current nuclear power plants, good utilization of fuel is a major economic issue. Major advances have yet to be achieved, to ensure longer in-reactor dwell-time, thus enabling fuel to yield more energy; and improve ruggedness. Aside from economics, and safety, such strategic issues as use of plutonium, conservation of resources, and nuclear waste management have to be addressed, and true technological challenges arise. This Monograph surveys current knowledge regarding in-reactor behavior, operating limits, and avenues for R and D. It also provides illustrations of ongoing research work, setting out a few noteworthy results recently achieved. Content: 1 - Introduction; 2 - Water reactor fuel: What are the features of water reactor fuel? 9 (What is the purpose of a nuclear fuel?, Ceramic fuel, Fuel rods, PWR fuel assemblies, BWR fuel assemblies); Fabrication of water reactor fuels (Fabrication of UO{sub 2} pellets, Fabrication of MOX (mixed uranium-plutonium oxide) pellets, Fabrication of claddings); In-reactor behavior of UO{sub 2} and MOX fuels (Irradiation conditions during nominal operation, Heat generation, and removal, The processes involved at the start of irradiation, Fission gas behavior, Microstructural changes); Water reactor fuel behavior in loss of tightness conditions (Cladding, the first containment barrier, Causes of failure, Consequences of a failure); Microscopic morphology of fuel ceramic and its evolution under irradiation; Migration and localization of fission products in UOX and MOX matrices (The ceramic under

  8. Efficiency of different techniques of physical flattening by fuel while selection of optimum arrangement of large fast reactor core

    International Nuclear Information System (INIS)

    Grachev, E.A.; Dejnega, N.L.; Mitin, A.M.

    1974-01-01

    Results are given of calculations for selecting the parameters of the large fast breeder reactor core (1500 Mw) operating on oxide fuel with a sodium coolant. A complex optimum criterion was selected for energy intensity, energy distribution, breeding ratio and critical load factor, run duration, burning, reactivity variations, influence of CV3, fuel overloads, and calculated fue fuel expenses. The effectivities of various methods for physical grading of fuel (enrichment and composition) were examined in accordance with the optimum criterion. Parameters of reactor cores optimum arrangements are presented. Continuous reactor operation during 0.8-1.0 yr. at energy intensity more than 400 kW was shown to be essential for attaining the optimum chosen. Accounting for the CV3 system and partial fuel overloads, the methods of balancing energy release either by enriching fuel or by changing its composition proved to be almost equally effective. All calculations were performed with the aid of a 18-4-RZ-15B program on the basis of a BNAB-26 constant system [ru

  9. Fuel assembly

    International Nuclear Information System (INIS)

    Bando, Masaru.

    1993-01-01

    As neutron irradiation progresses on a fuel assembly of an FBR type reactor, a strong force is exerted to cause ruptures if the arrangement of fuel elements is not displaced, whereas the fuel elements may be brought into direct contact with each other not by way of spacers to cause burning damages if the arrangement is displaced. In the present invention, the circumference of fuel elements arranged in a normal triangle lattice is surrounded by a wrapper tube having a hexagonal cross section, wire spacers are wound therearound, and deformable spacers are distributed to optional positions for fuel elements in the wrapper tube. Interaction between the fuel elements caused by irradiation is effectively absorbed, thereby enabling to delay the occurrence of the rupture and burning damages of the elements. (N.H.)

  10. Fuel Services

    International Nuclear Information System (INIS)

    Silberstein, A.

    1982-09-01

    FRAGEMA has developed most types of inspection equipments to work on irradiated fuel assemblies and on single fuel rods during reactor outages with an efficiency compatible with the utilities operating priorities. In order to illustrate this statement, two specific examples of inspection equipments are shortly described: the on-site removable fuel rod assembly examination stand, and the fuel assembly multiple examination device. FRAGEMA has developed techniques for the identifiction of the leaking fuel rods in the fuel assembly and the tooling necessary to perform the replacement of the faulted element. These examples of methods, techniques and equipments described and the experience accumulated through their use allow FRAGEMA to qualify for offering the supply of the corresponding software, hardware or both whenever an accurate understanding of the fuel behaviour is necessary and whenever direct intervention on the assembly and associated components is necessary due to safety, operating or economical reasons

  11. Soot Formation and Destruction in High-Pressure Flames with Real Fuels

    Science.gov (United States)

    2013-08-18

    Temperature and Oxygen Concentration on Diesel Spray Combustion Using a Single- Nozzle Injector in a Constant Volume Combustion Chamber, Combustion...enable the design of more efficient diesel engines. Higher efficiency will help reduce the logistical demand transportation fuels place on the entire...understanding of the soot formation processes at elevated pressure (e.g., 30 atm) will enable the design of more efficient diesel engines. Higher

  12. Energy Optimization on the Battlefield: How Integrating Energy Efficient Technologies at the Tactical Level Can Reduce Fuel Consumption and Lessen the Burden of Fuel Logistics

    Science.gov (United States)

    2014-06-13

    Alternative and Renewable fuels: FY10 NDAA, iv. 45Seth Robins, “Despite fracking boom, U.S. military still looks to biofuel over natural gas,” Stars...and Stripes, August 12, 2013, http://www.stripes.com/news/despite- fracking -boom-us-military-still-looks-to-biofuel-over-natural-gas-1.234403 (accessed...www.egsa.org/ LinkClick.aspx?fileticket=u3fZmFzYQD0%3D&tabid=262& (accessed April 29, 2014). Robins, Seth. “Despite fracking boom, U.S. military still

  13. Fuel cells

    NARCIS (Netherlands)

    Veen, van J.A.R.; Janssen, F.J.J.G.; Santen, van R.A.

    1999-01-01

    The principles and present-day embodiments of fuel cells are discussed. Nearly all cells are hydrogen/oxygen ones, where the hydrogen fuel is usually obtained on-site from the reforming of methane or methanol. There exists a tension between the promise of high efficiency in the conversion of

  14. Fuel Flexible, Low Emission Catalytic Combustor for Opportunity Fuel Applications

    Energy Technology Data Exchange (ETDEWEB)

    Eteman, Shahrokh

    2013-06-30

    Limited fuel resources, increasing energy demand and stringent emission regulations are drivers to evaluate process off-gases or process waste streams as fuels for power generation. Often these process waste streams have low energy content and/or highly reactive components. Operability of low energy content fuels in gas turbines leads to issues such as unstable and incomplete combustion. On the other hand, fuels containing higher-order hydrocarbons lead to flashback and auto-ignition issues. Due to above reasons, these fuels cannot be used directly without modifications or efficiency penalties in gas turbine engines. To enable the use of these wide variety of fuels in gas turbine engines a rich catalytic lean burn (RCL®) combustion system was developed and tested in a subscale high pressure (10 atm.) rig. The RCL® injector provided stability and extended turndown to low Btu fuels due to catalytic pre-reaction. Previous work has shown promise with fuels such as blast furnace gas (BFG) with LHV of 85 Btu/ft3 successfully combusted. This program extends on this work by further modifying the combustor to achieve greater catalytic stability enhancement. Fuels containing low energy content such as weak natural gas with a Lower Heating Value (LHV) of 6.5 MJ/m3 (180 Btu/ft3 to natural gas fuels containing higher hydrocarbon (e.g ethane) with LHV of 37.6 MJ/m3 (1010 Btu/ft3) were demonstrated with improved combustion stability; an extended turndown (defined as the difference between catalytic and non-catalytic lean blow out) of greater than 250oF was achieved with CO and NOx emissions lower than 5 ppm corrected to 15% O2. In addition, for highly reactive fuels the catalytic region preferentially pre-reacted the higher order hydrocarbons with no events of flashback or auto-ignition allowing a stable and safe operation with low NOx and CO emissions.

  15. A Benefit Analysis of Infusing Wireless into Aircraft and Fleet Operations - Report to Seedling Project Efficient Reconfigurable Cockpit Design and Fleet Operations Using Software Intensive, Network Enabled, Wireless Architecture (ECON)

    Science.gov (United States)

    Alexandrov, Natalia; Holmes, Bruce J.; Hahn, Andrew S.

    2016-01-01

    We report on an examination of potential benefits of infusing wireless technologies into various areas of aircraft and airspace operations. The analysis is done in support of a NASA seedling project Efficient Reconfigurable Cockpit Design and Fleet Operations Using Software Intensive, Network Enabled Wireless Architecture (ECON). The study has two objectives. First, we investigate one of the main benefit hypotheses of the ECON proposal: that the replacement of wired technologies with wireless would lead to significant weight reductions on an aircraft, among other benefits. Second, we advance a list of wireless technology applications and discuss their system benefits. With regard to the primary hypothesis, we conclude that the promise of weight reduction is premature. Specificity of the system domain and aircraft, criticality of components, reliability of wireless technologies, the weight of replacement or augmentation equipment, and the cost of infusion must all be taken into account among other considerations, to produce a reliable estimate of weight savings or increase.

  16. Fuel performance experience

    International Nuclear Information System (INIS)

    Sofer, G.A.

    1986-01-01

    The history of LWR fuel supply has been characterized by a wide range of design developments and fuel cycle cost improvements. Exxon Nuclear Company, Inc. has pursued an aggressive fuel research and development program aimed at improved fuel performance. Exxon Nuclear has introduced many design innovations which have improved fuel cycle economics and operating flexibility while fuel failures remain at very low levels. The removable upper tie plate feature of Exxon Nuclear assemblies has helped accelerate this development, enabling repeated inspections during successive plant outages. Also, this design feature has made it possible to repair damaged fuel assemblies during refueling outages, thereby minimizing the economic impact of fuel failure from all causes

  17. Pd and polyaniline nanocomposite on carbon fiber paper as an efficient direct formic acid fuel cell anode

    Science.gov (United States)

    Pandey, Rakesh K.

    2018-03-01

    Direct formic acid fuel cells are advantageous as portable power generating devices. In the present work, an anode catalyst for direct formic acid fuel cell (DFAFC) is presented which has good catalytic activity for formic acid oxidation. The catalyst is composed of Pd and conducting polymer polyaniline (Pd-PANI) nanocomposite. The catalyst was prepared by using a single step galvanostatic electrochemical deposition method. The Pd-PANI catalyst was electrodeposited at different time durations and a comparison of the catalytic activity at each deposition time was carried out and optimized.

  18. Nuclear fuels

    International Nuclear Information System (INIS)

    2008-01-01

    The nuclear fuel is one of the key component of a nuclear reactor. Inside it, the fission reactions of heavy atoms, uranium and plutonium, take place. It is located in the core of the reactor, but also in the core of the whole nuclear system. Its design and properties influence the behaviour, the efficiency and the safety of the reactor. Even if it represents a weak share of the generated electricity cost, its proper use represents an important economic stake. Important improvements remain to be made to increase its residence time inside the reactor, to supply more energy, and to improve its robustness. Beyond the economical and safety considerations, strategical questions have to find an answer, like the use of plutonium, the management of resources and the management of nuclear wastes and real technological challenges have to be taken up. This monograph summarizes the existing knowledge about the nuclear fuel, its behaviour inside the reactor, its limits of use, and its R and D tracks. It illustrates also the researches in progress and presents some key results obtained recently. Content: 1 - Introduction; 2 - The fuel of water-cooled reactors: aspect, fabrication, behaviour of UO 2 and MOX fuels inside the reactor, behaviour in loss of tightness situation, microscopic morphology of fuel ceramics and evolution under irradiation - migration and localisation of fission products in UOX and MOX matrices, modeling of fuels behaviour - modeling of defects and fission products in the UO 2 ceramics by ab initio calculations, cladding and assembly materials, pellet-cladding interaction, advanced UO 2 and MOX ceramics, mechanical behaviour of the fuel assembly, fuel during a loss of coolant accident, fuel during a reactivity accident, fuel during a serious accident, fuel management inside reactor cores, fuel cycle materials balance, long-term behaviour of the spent fuel, fuel of boiling water reactors; 3 - the fuel of liquid metal fast reactors: fast neutrons radiation

  19. Stratified charge rotary engine critical technology enablement. Volume 2: Appendixes

    Science.gov (United States)

    Irion, C. E.; Mount, R. E.

    1992-01-01

    This second volume of appendixes is a companion to Volume 1 of this report which summarizes results of a critical technology enablement effort with the stratified charge rotary engine (SCRE) focusing on a power section of 0.67 liters (40 cu. in.) per rotor in single and two rotor versions. The work is a continuation of prior NASA Contracts NAS3-23056 and NAS3-24628. Technical objectives are multi-fuel capability, including civil and military jet fuel and DF-2, fuel efficiency of 0.355 Lbs/BHP-Hr. at best cruise condition above 50 percent power, altitude capability of up to 10Km (33,000 ft.) cruise, 2000 hour TBO and reduced coolant heat rejection. Critical technologies for SCRE's that have the potential for competitive performance and cost in a representative light-aircraft environment were examined. Objectives were: the development and utilization of advanced analytical tools, i.e. higher speed and enhanced three dimensional combustion modeling; identification of critical technologies; development of improved instrumentation; and to isolate and quantitatively identify the contribution to performance and efficiency of critical components or subsystems. A family of four-stage third-order explicit Runge-Kutta schemes is derived that required only two locations and has desirable stability characteristics. Error control is achieved by embedding a second-order scheme within the four-stage procedure. Certain schemes are identified that are as efficient and accurate as conventional embedded schemes of comparable order and require fewer storage locations.

  20. Characterization of Regional Marginal Abatement Cost Curves for NOx that Incorporate Control Measures, Renewable Energy, Energy Efficiency and Fuel Switching

    Science.gov (United States)

    Anthropogenic nitrogen oxides (NOx) are emitted when fossil fuels are combusted. In the atmosphere, NOx reacts with volatile organic compounds (VOCs) to produce tropospheric ozone, a component of photochemical smog. In most parts of the country, strategies for reducing ozone gene...