WorldWideScience

Sample records for energy efficient thermal

  1. Energy efficient thermal management of data centers

    CERN Document Server

    Kumar, Pramod

    2012-01-01

    Energy Efficient Thermal Management of Data Centers examines energy flow in today's data centers. Particular focus is given to the state-of-the-art thermal management and thermal design approaches now being implemented across the multiple length scales involved. The impact of future trends in information technology hardware, and emerging software paradigms such as cloud computing and virtualization, on thermal management are also addressed. The book explores computational and experimental characterization approaches for determining temperature and air flow patterns within data centers. Thermodynamic analyses using the second law to improve energy efficiency are introduced and used in proposing improvements in cooling methodologies. Reduced-order modeling and robust multi-objective design of next generation data centers are discussed. This book also: Provides in-depth treatment of energy efficiency ideas based on  fundamental heat transfer, fluid mechanics, thermodynamics, controls, and computer science Focus...

  2. More Efficient Solar Thermal-Energy Receiver

    Science.gov (United States)

    Dustin, M. O.

    1987-01-01

    Thermal stresses and reradiation reduced. Improved design for solar thermal-energy receiver overcomes three major deficiencies of solar dynamic receivers described in literature. Concentrator and receiver part of solar-thermal-energy system. Receiver divided into radiation section and storage section. Concentrated solar radiation falls on boiling ends of heat pipes, which transmit heat to thermal-energy-storage medium. Receiver used in number of applications to produce thermal energy directly for use or to store thermal energy for subsequent use in heat engine.

  3. Thermal power plant efficiency enhancement with Ocean Thermal Energy Conversion

    International Nuclear Information System (INIS)

    Soto, Rodrigo; Vergara, Julio

    2014-01-01

    In addition to greenhouse gas emissions, coastal thermal power plants would gain further opposition due to their heat rejection distressing the local ecosystem. Therefore, these plants need to enhance their thermal efficiency while reducing their environmental offense. In this study, a hybrid plant based on the principle of Ocean Thermal Energy Conversion was coupled to a 740 MW coal-fired power plant project located at latitude 28°S where the surface to deepwater temperature difference would not suffice for regular OTEC plants. This paper presents the thermodynamical model to assess the overall efficiency gained by adopting an ammonia Rankine cycle plus a desalinating unit, heated by the power plant condenser discharge and refrigerated by cold deep seawater. The simulation allowed us to optimize a system that would finally enhance the plant power output by 25–37 MW, depending on the season, without added emissions while reducing dramatically the water temperature at discharge and also desalinating up to 5.8 million tons per year. The supplemental equipment was sized and the specific emissions reduction was estimated. We believe that this approach would improve the acceptability of thermal and nuclear power plant projects regardless of the plant location. -- Highlights: • An Ocean Thermal Energy Conversion hybrid plant was designed. • The waste heat of a power plant was delivered as an OTEC heat source. • The effect of size and operating conditions on plant efficiency were studied. • The OTEC implementation in a Chilean thermal power plant was evaluated. • The net efficiency of the thermal power plant was increased by 1.3%

  4. Improving Energy Efficiency In Thermal Oil Recovery Surface Facilities

    Energy Technology Data Exchange (ETDEWEB)

    Murthy Nadella, Narayana

    2010-09-15

    Thermal oil recovery methods such as Cyclic Steam Stimulation (CSS), Steam Assisted Gravity Drainage (SAGD) and In-situ Combustion are being used for recovering heavy oil and bitumen. These processes expend energy to recover oil. The process design of the surface facilities requires optimization to improve the efficiency of oil recovery by minimizing the energy consumption per barrel of oil produced. Optimization involves minimizing external energy use by heat integration. This paper discusses the unit processes and design methodology considering thermodynamic energy requirements and heat integration methods to improve energy efficiency in the surface facilities. A design case study is presented.

  5. Influences on the thermal efficiency of energy piles

    International Nuclear Information System (INIS)

    Cecinato, Francesco; Loveridge, Fleur A.

    2015-01-01

    Energy piles have recently emerged as a viable alternative to borehole heat exchangers, but their energy efficiency has so far seen little research. In this work, a finite element numerical model is developed for the accurate 3D analysis of transient diffusive and convective heat exchange phenomena taking place in geothermal structures. The model is validated by reproducing both the outcome of a thermal response test carried out on a test pile, and the average response of the linear heat source analytical solution. Then, the model is employed to carry out a parametric analysis to identify the key factors in maximising the pile energy efficiency. It is shown that the most influential design parameter is the number of pipes, which can be more conveniently increased, within a reasonable range, compared to increasing the pile dimensions. The influence of changing pile length, concrete conductivity, pile diameter and concrete cover are also discussed in light of their energetic implications. Counter to engineering intuition, the fluid flowrate does not emerge as important in energy efficiency, provided it is sufficient to ensure turbulent flow. The model presented in this paper can be easily adapted to the detailed study of other types of geothermal structures. - Highlights: • A numerical model for 3D thermal transient analysis of energy piles is developed. • The model is validated against both field data and an analytical solution. • Key parameters are then identified for efficient thermal design of energy piles. • Energy efficiency is maximised by large pipe number and concrete conductivity. • Large exchanger fluid velocity does not have a major impact on efficiency

  6. High Efficiency and Low Cost Thermal Energy Storage System

    Energy Technology Data Exchange (ETDEWEB)

    Sienicki, James J. [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Lv, Qiuping [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Moisseytsev, Anton [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division; Bucknor, Matthew [Argonne National Lab. (ANL), Argonne, IL (United States). Nuclear Engineering Division

    2017-09-29

    BgtL, LLC (BgtL) is focused on developing and commercializing its proprietary compact technology for processes in the energy sector. One such application is a compact high efficiency Thermal Energy Storage (TES) system that utilizes the heat of fusion through phase change between solid and liquid to store and release energy at high temperatures and incorporate state-of-the-art insulation to minimize heat dissipation. BgtL’s TES system would greatly improve the economics of existing nuclear and coal-fired power plants by allowing the power plant to store energy when power prices are low and sell power into the grid when prices are high. Compared to existing battery storage technology, BgtL’s novel thermal energy storage solution can be significantly less costly to acquire and maintain, does not have any waste or environmental emissions, and does not deteriorate over time; it can keep constant efficiency and operates cleanly and safely. BgtL’s engineers are experienced in this field and are able to design and engineer such a system to a specific power plant’s requirements. BgtL also has a strong manufacturing partner to fabricate the system such that it qualifies for an ASME code stamp. BgtL’s vision is to be the leading provider of compact systems for various applications including energy storage. BgtL requests that all technical information about the TES designs be protected as proprietary information. To honor that request, only non-proprietay summaries are included in this report.

  7. High efficiency thermal energy storage system for utility applications

    International Nuclear Information System (INIS)

    Vrable, D.L.; Quade, R.N.

    1979-01-01

    A concept of coupling a high efficiency base loaded coal or nuclear power plant with a thermal energy storage scheme for efficient and low-cost intermediate and peaking power is presented. A portion of the power plant's thermal output is used directly to generate superheated steam for continuous operation of a conventional turbine-generator to product base-load power. The remaining thermal output is used on a continuous basis to heat a conventional heat transfer salt (such as the eutectic composition of KaNO 3 /NaNO 3 /NaNO 2 ), which is stored in a high-temperature reservoir [538 0 C (1000 0 F)]. During peak demand periods, the salt is circulated from the high-temperature reservoir to a low-temperature reservoir through steam generators in order to provide peaking power from a conventional steam cycle plant. The period of operation can vary, but may typically be the equivalent of about 4 to 8 full-power hours each day. The system can be tailored to meet the utilities' load demand by varying the base-load level and the period of operation of the peak-load system

  8. Advances in Thermal Insulation. Vacuum Insulation Panels and Thermal Efficiency to Reduce Energy Usage in Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Thorsell, Thomas

    2012-07-01

    procedure incorporates specific steps exposing the wall to different climate conditions, ranging from cold and dry to hot and humid, with and without a pressure gradient. This study showed that air infiltration alone might decrease the thermal resistance of a residential wall by 15 %, more for industrial walls. Results from the research underpin a discussion concerning the importance of a holistic approach to building design if we are to meet the challenge of energy savings and sustainability. Thermal insulation efficiency is a main concept used throughout, and since it measures utilization it is a partial measure of sustainability. It is therefore proposed as a necessary design parameter in addition to a performance indicator when designing building envelopes. The thermal insulation efficiency ranges from below 50 % for a wood stud wall poorly designed with incorporated VIP, while an optimized design with VIP placed in an uninterrupted external layer shows an efficiency of 99 %, almost perfect. Thermal insulation efficiency reflects the measured wall performance full scale test, thus indicating efficiency under varied environmental loads: heat, moisture and pressure. The building design must be as a system, integrating all the subsystems together to function in concert. New design methodologies must be created along with new, more reliable and comprehensive measuring, testing and integrating procedures. New super insulators are capable of reducing energy usage below zero energy in buildings. It would be a shame to waste them by not taking care of the rest of the system. This thesis details the steps that went into this study and shows how this can be done Key words: Vacuum insulation panels, VIP, serpentine edge, thermal bridge, composite film, gas diffusion, defect dominated, holistic approach, building enclosure, integrated testing and modeling, energy equivalent, field performance, air flow, thermal insulation efficiency.

  9. Efficient Solar-Thermal Energy Harvest Driven by Interfacial Plasmonic Heating-Assisted Evaporation.

    Science.gov (United States)

    Chang, Chao; Yang, Chao; Liu, Yanming; Tao, Peng; Song, Chengyi; Shang, Wen; Wu, Jianbo; Deng, Tao

    2016-09-07

    The plasmonic heating effect of noble nanoparticles has recently received tremendous attention for various important applications. Herein, we report the utilization of interfacial plasmonic heating-assisted evaporation for efficient and facile solar-thermal energy harvest. An airlaid paper-supported gold nanoparticle thin film was placed at the thermal energy conversion region within a sealed chamber to convert solar energy into thermal energy. The generated thermal energy instantly vaporizes the water underneath into hot vapors that quickly diffuse to the thermal energy release region of the chamber to condense into liquids and release the collected thermal energy. The condensed water automatically flows back to the thermal energy conversion region under the capillary force from the hydrophilic copper mesh. Such an approach simultaneously realizes efficient solar-to-thermal energy conversion and rapid transportation of converted thermal energy to target application terminals. Compared to conventional external photothermal conversion design, the solar-thermal harvesting device driven by the internal plasmonic heating effect has reduced the overall thermal resistance by more than 50% and has demonstrated more than 25% improvement of solar water heating efficiency.

  10. Energy Efficiency Enhancement of Photovoltaics by Phase Change Materials through Thermal Energy Recovery

    Directory of Open Access Journals (Sweden)

    Ahmad Hasan

    2016-09-01

    Full Text Available Photovoltaic (PV panels convert a certain amount of incident solar radiation into electricity, while the rest is converted to heat, leading to a temperature rise in the PV. This elevated temperature deteriorates the power output and induces structural degradation, resulting in reduced PV lifespan. One potential solution entails PV thermal management employing active and passive means. The traditional passive means are found to be largely ineffective, while active means are considered to be energy intensive. A passive thermal management system using phase change materials (PCMs can effectively limit PV temperature rises. The PCM-based approach however is cost inefficient unless the stored thermal energy is recovered effectively. The current article investigates a way to utilize the thermal energy stored in the PCM behind the PV for domestic water heating applications. The system is evaluated in the winter conditions of UAE to deliver heat during water heating demand periods. The proposed system achieved a ~1.3% increase in PV electrical conversion efficiency, along with the recovery of ~41% of the thermal energy compared to the incident solar radiation.

  11. Ambient Temperature Based Thermal Aware Energy Efficient ROM Design on FPGA

    DEFF Research Database (Denmark)

    Saini, Rishita; Bansal, Neha; Bansal, Meenakshi

    2015-01-01

    Thermal aware design is currently gaining importance in VLSI research domain. In this work, we are going to design thermal aware energy efficient ROM on Virtex-5 FPGA. Ambient Temperature, airflow, and heat sink profile play a significant role in thermal aware hardware design life cycle. Ambient...

  12. Influence of reflectance from flat aluminum concentrators on energy efficiency of PV/Thermal collector

    International Nuclear Information System (INIS)

    Kostic, Ljiljana T.; Pavlovic, Tomislav M.; Pavlovic, Zoran T.

    2010-01-01

    In this paper the results of the influence of reflectance from flat plate solar radiation concentrators made of Al sheet and Al foil on energy efficiency of PV/Thermal collector are presented. The total reflectance from concentrators made of Al sheet and Al foil is almost the same, but specular reflectance which is bigger in concentrators made of Al foil results in increase of solar radiation intensity concentration factor. With the increase of solar radiation intensity concentration factor, total daily thermal and electrical energy generated by PV/Thermal collector with concentrators increase. In this work also optimal position of solar radiation concentrators made of Al sheet and Al foil and appropriate thermal and electrical efficiency of PV/Thermal collector have been determined. Total energy generated by PV/Thermal collector with concentrators made of Al foil in optimal position is higher than total energy generated by PV/Thermal collector with concentrators made of Al sheet.

  13. Characteristics Study of Photovoltaic Thermal System with Emphasis on Energy Efficiency

    Directory of Open Access Journals (Sweden)

    Yong Chuah Yee

    2018-01-01

    Full Text Available Solar energy is typically collected through photovoltaic (PV to generate electricity or through thermal collectors as heat energy, they are generally utilised separately. This project is done with the purpose of integrating the two systems to improve the energy efficiency. The idea of this photovoltaic-thermal (PVT setup design is to simultaneously cool the PV panel so it can operate at a lower temperature thus higher electrical efficiency and also store the thermal energy. The experimental data shows that the PVT setup increased the electrical efficiency of the standard PV setup from 1.64% to 2.15%. The integration of the thermal collector also allowed 37.25% of solar energy to be stored as thermal energy. The standard PV setup harnessed only 1.64% of the solar energy, whereas the PVT setup achieved 39.4%. Different flowrates were tested to determine its effects on the PVT setup’s electrical and thermal efficiency. The various flowrate does not significantly impact the electrical efficiency since it did not significantly impact the cooling of the panel. The various flowrates resulted in fluctuating thermal efficiencies, the relation between the two is inconclusive in this project.

  14. Passive Collecting of Solar Radiation Energy using Transparent Thermal Insulators, Energetic Efficiency of Transparent Thermal Insulators

    Directory of Open Access Journals (Sweden)

    Smajo Sulejmanovic

    2014-11-01

    Full Text Available This paper explains passive collection of solar radiation energy using transparent thermal insulators. Transparent thermal insulators are transparent for sunlight, at the same time those are very good thermal insulators. Transparent thermal insulators can be placed instead of standard conventional thermal insulators and additionally transparent insulators can capture solar radiation, transform it into heat and save heat just as standard insulators. Using transparent insulators would lead to reduce in usage of fossil fuels and would help protection of an environment and reduce effects of global warming, etc.

  15. The energy efficiency ratio of heat storage in one shell-and-one tube phase change thermal energy storage unit

    International Nuclear Information System (INIS)

    Wang, Wei-Wei; Wang, Liang-Bi; He, Ya-Ling

    2015-01-01

    Highlights: • A parameter to indicate the energy efficiency ratio of PCTES units is defined. • The characteristics of the energy efficiency ratio of PCTES units are reported. • A combined parameter of the physical properties of the working mediums is found. • Some implications of the energy efficiency ratio in design of PCTES units are analyzed. - Abstract: From aspect of energy consuming to pump heat transfer fluid, there is no sound basis on which to create an optimum design of a thermal energy storage unit. Thus, it is necessary to develop a parameter to indicate the energy efficiency of such unit. This paper firstly defines a parameter that indicates the ratio of heat storage of phase change thermal energy storage unit to energy consumed in pumping heat transfer fluid, which is called the energy efficiency ratio, then numerically investigates the characteristics of this parameter. The results show that the energy efficiency ratio can clearly indicate the energy efficiency of a phase change thermal energy storage unit. When the fluid flow of a heat transfer fluid is in a laminar state, the energy efficiency ratio is larger than in a turbulent state. The energy efficiency ratio of a shell-and-tube phase change thermal energy storage unit is more sensitive to the outer tube diameter. Under the same working conditions, within the heat transfer fluids studied, the heat storage property of the phase change thermal energy storage unit is best for water as heat transfer fluid. A combined parameter is found to indicate the effects of both the physical properties of phase change material and heat transfer fluid on the energy efficiency ratio

  16. Heat transfer efficient thermal energy storage for steam generation

    International Nuclear Information System (INIS)

    Adinberg, R.; Zvegilsky, D.; Epstein, M.

    2010-01-01

    A novel reflux heat transfer storage (RHTS) concept for producing high-temperature superheated steam in the temperature range 350-400 deg. C was developed and tested. The thermal storage medium is a metallic substance, Zinc-Tin alloy, which serves as the phase change material (PCM). A high-temperature heat transfer fluid (HTF) is added to the storage medium in order to enhance heat exchange within the storage system, which comprises PCM units and the associated heat exchangers serving for charging and discharging the storage. The applied heat transfer mechanism is based on the HTF reflux created by a combined evaporation-condensation process. It was shown that a PCM with a fraction of 70 wt.% Zn in the alloy (Zn70Sn30) is optimal to attain a storage temperature of 370 deg. C, provided the heat source such as solar-produced steam or solar-heated synthetic oil has a temperature of about 400 deg. C (typical for the parabolic troughs technology). This PCM melts gradually between temperatures 200 and 370 deg. C preserving the latent heat of fusion, mainly of the Zn-component, that later, at the stage of heat discharge, will be available for producing steam. The thermal storage concept was experimentally studied using a lab scale apparatus that enabled investigating of storage materials (the PCM-HTF system) simultaneously with carrying out thermal performance measurements and observing heat transfer effects occurring in the system. The tests produced satisfactory results in terms of thermal stability and compatibility of the utilized storage materials, alloy Zn70Sn30 and the eutectic mixture of biphenyl and diphenyl oxide, up to a working temperature of 400 deg. C. Optional schemes for integrating the developed thermal storage into a solar thermal electric plant are discussed and evaluated considering a pilot scale solar plant with thermal power output of 12 MW. The storage should enable uninterrupted operation of solar thermal electric systems during additional hours

  17. Research of waste heat energy efficiency for absorption heat pump recycling thermal power plant circulating water

    Science.gov (United States)

    Zhang, Li; Zhang, Yu; Zhou, Liansheng; E, Zhijun; Wang, Kun; Wang, Ziyue; Li, Guohao; Qu, Bin

    2018-02-01

    The waste heat energy efficiency for absorption heat pump recycling thermal power plant circulating water has been analyzed. After the operation of heat pump, the influences on power generation and heat generation of unit were taken into account. In the light of the characteristics of heat pump in different operation stages, the energy efficiency of heat pump was evaluated comprehensively on both sides of benefits belonging to electricity and benefits belonging to heat, which adopted the method of contrast test. Thus, the reference of energy efficiency for same type projects was provided.

  18. Hierarchical Graphene Foam for Efficient Omnidirectional Solar-Thermal Energy Conversion.

    Science.gov (United States)

    Ren, Huaying; Tang, Miao; Guan, Baolu; Wang, Kexin; Yang, Jiawei; Wang, Feifan; Wang, Mingzhan; Shan, Jingyuan; Chen, Zhaolong; Wei, Di; Peng, Hailin; Liu, Zhongfan

    2017-10-01

    Efficient solar-thermal energy conversion is essential for the harvesting and transformation of abundant solar energy, leading to the exploration and design of efficient solar-thermal materials. Carbon-based materials, especially graphene, have the advantages of broadband absorption and excellent photothermal properties, and hold promise for solar-thermal energy conversion. However, to date, graphene-based solar-thermal materials with superior omnidirectional light harvesting performances remain elusive. Herein, hierarchical graphene foam (h-G foam) with continuous porosity grown via plasma-enhanced chemical vapor deposition is reported, showing dramatic enhancement of broadband and omnidirectional absorption of sunlight, which thereby can enable a considerable elevation of temperature. Used as a heating material, the external solar-thermal energy conversion efficiency of the h-G foam impressively reaches up to ≈93.4%, and the solar-vapor conversion efficiency exceeds 90% for seawater desalination with high endurance. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. High efficiency thermal to electric energy conversion using selective emitters and spectrally tuned solar cells

    Science.gov (United States)

    Chubb, Donald L.; Flood, Dennis J.; Lowe, Roland A.

    1992-01-01

    Thermophotovoltaic (TPV) systems are attractive possibilities for direct thermal-to-electric energy conversion, but have typically required the use of black body radiators operating at high temperatures. Recent advances in both the understanding and performance of solid rare-earth oxide selective emitters make possible the use of TPV at temperatures as low as 1500 K. Depending on the nature of parasitic losses, overall thermal-to-electric conversion efficiencies greater than 20 percent are feasible.

  20. Energy subsidies in Argentina lead to inequalities and low thermal efficiency

    International Nuclear Information System (INIS)

    Gonzalez, A. D.

    2009-01-01

    Natural gas is the main energy resource for buildings in Argentina. Since 2002, subsidies have kept the prices of this fuel between 9 and 26 times lower than regular prices in other countries. The lowest prices are the result of climate-related subsidies. In cold areas, heating uses several times more energy than locations in Europe with a similar climate. A potential for consumption reductions of up to 70% suggests a very low building thermal performance. The main barriers to finding a solution are the heavy subsidies and public unawareness. Users, government officials, and construction professionals do not identify the very low thermal efficiency. Energy policies to encourage improvements are proposed. (author)

  1. Efficient thermal desalination technologies with renewable energy systems: A state-of-the-art review

    International Nuclear Information System (INIS)

    Esfahani, Iman Janghorban; Rashidi, Jouan; Ifaei, Pouya; Yoo, ChangKyoo

    2016-01-01

    Due to the current fossil fuel crisis and associated adverse environmental impacts, renewable energy sources (RES) have drawn interest as alternatives to fossil fuels for powering water desalination systems. Over the last few decades the utility of renewable energy sources such as solar, geothermal, and wind to run desalination processes has been explored. However, the expansion of these technologies to larger scales is hampered by techno-economic and thermo-economic challenges. This paper reviews the state-of-the-art in the field of renewable energy-powered thermal desalination systems (RE-PTD) to compare their productivity and efficiency through thermodynamic, economic, and environmental analyses. We performed a comparative study using published data to classify RE-PTD systems technologies on the basis of the energy collection systems that they use. Among RE-PTD systems, solar energy powered-thermal desalination systems demonstrate high thermo-environ-economic efficiency to produce fresh water to meet various scales of demand.

  2. Efficient thermal desalination technologies with renewable energy systems: A state-of-the-art review

    Energy Technology Data Exchange (ETDEWEB)

    Esfahani, Iman Janghorban; Rashidi, Jouan; Ifaei, Pouya; Yoo, ChangKyoo [Center for Environmental Studies, Kyung Hee University, Yongin (Korea, Republic of)

    2016-02-15

    Due to the current fossil fuel crisis and associated adverse environmental impacts, renewable energy sources (RES) have drawn interest as alternatives to fossil fuels for powering water desalination systems. Over the last few decades the utility of renewable energy sources such as solar, geothermal, and wind to run desalination processes has been explored. However, the expansion of these technologies to larger scales is hampered by techno-economic and thermo-economic challenges. This paper reviews the state-of-the-art in the field of renewable energy-powered thermal desalination systems (RE-PTD) to compare their productivity and efficiency through thermodynamic, economic, and environmental analyses. We performed a comparative study using published data to classify RE-PTD systems technologies on the basis of the energy collection systems that they use. Among RE-PTD systems, solar energy powered-thermal desalination systems demonstrate high thermo-environ-economic efficiency to produce fresh water to meet various scales of demand.

  3. Efficiency gains of photovoltaic system using latent heat thermal energy storage

    NARCIS (Netherlands)

    Tan, Lippong; Date, Abhijit; Fernandes, Gabriel; Singh, Baljit; Ganguly, Sayantan

    This paper presents experimental assessments of the thermal and electrical performance of photovoltaic (PV) system by comparing the latent heat-cooled PV panel with the naturally-cooled equivalent. It is commonly known that the energy conversion efficiency of the PV cells declines with the increment

  4. High thermal efficiency x-ray energy conversion scheme for advanced fusion reactors

    International Nuclear Information System (INIS)

    Quimby, D.C.; Taussig, R.T.; Hertzberg, A.

    1977-01-01

    This paper reports on a new radiation energy conversion scheme which appears to be capable of producing electricity from the high quality x-ray energy with efficiencies of 60 to 70 percent. This new reactor concept incorporates a novel x-ray radiation boiler and a new thermal conversion device known as an energy exchanger. The low-Z first walls of the radiation boiler are semi-transparent to x-rays, and are kept cool by incoming working fluid, which is subsequently heated to temperatures of 2000 to 3000 0 K in the interior of the boiler by volumetric x-ray absorption. The radiation boiler may be a compact part of the reactor shell since x-rays are readily absorbed in high-Z materials. The energy exchanger transfers the high-temperature working fluid energy to a lower temperature gas which drives a conventional turbine. The overall efficiency of the cycle is characterized by the high temperature of the working fluid. The high thermal efficiencies which appear achievable with this cycle would make an otherwise marginal advanced fusion reactor into an attractive net power producer. The operating principles, initial conceptual design, and engineering problems of the radiation boiler and thermal cycle are presented

  5. Energy efficiency and pollution control for thermal units in the Egyptian industry

    International Nuclear Information System (INIS)

    Said Abdel-wahab; Ismail, W.M.

    1999-01-01

    Energy conservation and environmental protection project (ECEP) is a Usaid sponsored project. Its main objective is to promote energy conservation and pollution protection in the egyptian industry through a group of demonstrated projects. One of the implemented activities is the boilers and furnaces tune-up program, which aims to increase energy efficiency and reduce pollution. To achieve this objective. (ECEP) distributed 100 electronic portable exhaust gas analyzers to cover eight industrial sectors at six different geographical locations in egypt. These analyzers were used to measure the contents of exhaust gases to help operators tune up their equipment on regular basis. The result is that the firing thermal units operate at the highest possible combustion efficiency to reduce the amount of fuel consumption as well as pollution emissions. The analyzer used measures two types of temperature, five different stack gases, draft and smoke density. moreover it computes the efficiency of combustion as well as Co2 and excess air percentage. Thermal units that rested by these analyzers were consuming a huge amount of fossil fuel from different types. The average combustion efficiency for thermal units tested was improved by 14%, 15% and 28% for boilers, furnaces and diesel respectively

  6. Energy efficient hybrid nanocomposite-based cool thermal storage air conditioning system for sustainable buildings

    International Nuclear Information System (INIS)

    Parameshwaran, R.; Kalaiselvam, S.

    2013-01-01

    The quest towards energy conservative building design is increasingly popular in recent years, which has triggered greater interests in developing energy efficient systems for space cooling in buildings. In this work, energy efficient silver–titania HiTES (hybrid nanocomposites-based cool thermal energy storage) system combined with building A/C (air conditioning) system was experimentally investigated for summer and winter design conditions. HiNPCM (hybrid nanocomposite particles embedded PCM) used as the heat storage material has exhibited 7.3–58.4% of improved thermal conductivity than at its purest state. The complete freezing time for HiNPCM was reduced by 15% which was attributed to its improved thermophysical characteristics. Experimental results suggest that the effective energy redistribution capability of HiTES system has contributed for reduction in the chiller nominal cooling capacity by 46.3% and 39.6% respectively, under part load and on-peak load operating conditions. The HiTES A/C system achieved 27.3% and 32.5% of on-peak energy savings potential in summer and winter respectively compared to the conventional A/C system. For the same operating conditions, this system yield 8.3%, 12.2% and 7.2% and 10.2% of per day average and yearly energy conservation respectively. This system can be applied for year-round space conditioning application without sacrificing energy efficiency in buildings. - Highlights: • Energy storage is acquired by HiTES (hybrid nanocomposites-thermal storage) system. • Thermal conductivity of HiNPCM (hybrid nanocomposites-PCM) was improved by 58.4%. • Freezing time of HiNPCM was reduced by 15% that enabled improved energy efficiency. • Chiller nominal capacity was reduced by 46.3% and 39.6% in on-peak and part load respectively. • HiTES A/C system achieved appreciable energy savings in the range of 8.3–12.2%

  7. A thermally regenerative ammonia-based battery for efficient harvesting of low-grade thermal energy as electrical power

    KAUST Repository

    Zhang, Fang

    2015-01-01

    © 2015 The Royal Society of Chemistry. Thermal energy was shown to be efficiently converted into electrical power in a thermally regenerative ammonia-based battery (TRAB) using copper-based redox couples [Cu(NH3)4 2+/Cu and Cu(ii)/Cu]. Ammonia addition to the anolyte (2 M ammonia in a copper-nitrate electrolyte) of a single TRAB cell produced a maximum power density of 115 ± 1 W m-2 (based on projected area of a single copper mesh electrode), with an energy density of 453 W h m-3 (normalized to the total electrolyte volume, under maximum power production conditions). Adding a second cell doubled both the voltage and maximum power. Increasing the anolyte ammonia concentration to 3 M further improved the maximum power density to 136 ± 3 W m-2. Volatilization of ammonia from the spent anolyte by heating (simulating distillation), and re-addition of this ammonia to the spent catholyte chamber with subsequent operation of this chamber as the anode (to regenerate copper on the other electrode), produced a maximum power density of 60 ± 3 W m-2, with an average discharge energy efficiency of ∼29% (electrical energy captured versus chemical energy in the starting solutions). Power was restored to 126 ± 5 W m-2 through acid addition to the regenerated catholyte to decrease pH and dissolve Cu(OH)2 precipitates, suggesting that an inexpensive acid or a waste acid could be used to improve performance. These results demonstrated that TRABs using ammonia-based electrolytes and inexpensive copper electrodes can provide a practical method for efficient conversion of low-grade thermal energy into electricity.

  8. Energy efficiency

    International Nuclear Information System (INIS)

    2010-01-01

    After a speech of the CEA's (Commissariat a l'Energie Atomique) general administrator about energy efficiency as a first rank challenge for the planet and for France, this publications proposes several contributions: a discussion of the efficiency of nuclear energy, an economic analysis of R and D's value in the field of fourth generation fast reactors, discussions about biofuels and the relationship between energy efficiency and economic competitiveness, and a discussion about solar photovoltaic efficiency

  9. Sensitivity analysis of recovery efficiency in high-temperature aquifer thermal energy storage with single well

    International Nuclear Information System (INIS)

    Jeon, Jun-Seo; Lee, Seung-Rae; Pasquinelli, Lisa; Fabricius, Ida Lykke

    2015-01-01

    High-temperature aquifer thermal energy storage system usually shows higher performance than other borehole thermal energy storage systems. Although there is a limitation in the widespread use of the HT-ATES system because of several technical problems such as clogging, corrosion, etc., it is getting more attention as these issues are gradually alleviated. In this study, a sensitivity analysis of recovery efficiency in two cases of HT-ATES system with a single well is conducted to select key parameters. For a fractional factorial design used to choose input parameters with uniformity, the optimal Latin hypercube sampling with an enhanced stochastic evolutionary algorithm is considered. Then, the recovery efficiency is obtained using a computer model developed by COMSOL Multiphysics. With input and output variables, the surrogate modeling technique, namely the Gaussian-Kriging method with Smoothly Clopped Absolute Deviation Penalty, is utilized. Finally, the sensitivity analysis is performed based on the variation decomposition. According to the result of sensitivity analysis, the most important input variables are selected and confirmed to consider the interaction effects for each case and it is confirmed that key parameters vary with the experiment domain of hydraulic and thermal properties as well as the number of input variables. - Highlights: • Main and interaction effects on recovery efficiency in HT-ATES was investigated. • Reliability depended on fractional factorial design and interaction effects. • Hydraulic permeability of aquifer had an important impact on recovery efficiency. • Site-specific sensitivity analysis of HT-ATES was recommended.

  10. Energy Savings Through Thermally Efficient Crucible Technology: Fundamentals, Process Modeling, and Applications

    Science.gov (United States)

    Shi, Wenwu; Pinto, Brian

    2017-12-01

    Melting and holding molten metals within crucibles accounts for a large portion of total energy demand in the resource-intensive nonferrous foundry industry. Multivariate mathematical modeling aided by detailed material characterization and advancements in crucible technologies can make a significant impact in the areas of cost-efficiency and carbon footprint reduction. Key thermal properties such as conductivity and specific heat capacity were studied to understand their influence on crucible furnace energy consumption during melting and holding processes. The effects of conductivity on thermal stresses and longevity of crucibles were also evaluated. With this information, accurate theoretical models using finite element analysis were developed to study total energy consumption and melting time. By applying these findings to recent crucible developments, considerable improvements in field performance were reported and documented as case studies in applications such as aluminum melting and holding.

  11. Thermal inertia and energy efficiency – Parametric simulation assessment on a calibrated case study

    International Nuclear Information System (INIS)

    Aste, Niccolò; Leonforte, Fabrizio; Manfren, Massimiliano; Mazzon, Manlio

    2015-01-01

    Highlights: • We perform a parametric simulation study on a calibrated building energy model. • We introduce adaptive shadings and night free cooling in simulations. • We analyze the effect of thermal capacity on the parametric simulations results. • We recognize that cooling demand and savings scales linearly with thermal capacity. • We assess the advantage of medium-heavy over medium and light configurations. - Abstract: The reduction of energy consumption for heating and cooling services in the existing building stock is a key challenge for global sustainability today and buildings’ envelopes retrofit is one the main issues. Most of the existing buildings’ envelopes have low levels of insulation, high thermal losses due to thermal bridges and cracks, absence of appropriate solar control, etc. Further, in building refurbishment, the importance of a system level approach is often undervalued in favour of simplistic “off the shelf” efficient solutions, focused on the reduction of thermal transmittance and on the enhancement of solar control capabilities. In many cases, the importance of the dynamic thermal properties is often neglected or underestimated and the effective thermal capacity is not properly considered as one of the design parameters. The research presented aims to critically assess the influence of the dynamic thermal properties of the building fabric (roof, walls and floors) on sensible heating and cooling energy demand for a case study. The case study chosen is an existing office building which has been retrofitted in recent years and whose energy model has been calibrated according to the data collected in the monitoring process. The research illustrates the variations of the sensible thermal energy demand of the building in different retrofit scenarios, and relates them to the variations of the dynamic thermal properties of the construction components. A parametric simulation study has been performed, encompassing the use of

  12. Methods to determine stratification efficiency of thermal energy storage processes–Review and theoretical comparison

    DEFF Research Database (Denmark)

    Haller, Michel; Cruickshank, Chynthia; Streicher, Wolfgang

    2009-01-01

    This paper reviews different methods that have been proposed to characterize thermal stratification in energy storages from a theoretical point of view. Specifically, this paper focuses on the methods that can be used to determine the ability of a storage to promote and maintain stratification...... during charging, storing and discharging, and represent this ability with a single numerical value in terms of a stratification efficiency for a given experiment or under given boundary conditions. Existing methods for calculating stratification efficiencies have been applied to hypothetical storage...

  13. A method to determine stratification efficiency of thermal energy storage processes independently from storage heat losses

    DEFF Research Database (Denmark)

    Haller, M.Y.; Yazdanshenas, Eshagh; Andersen, Elsa

    2010-01-01

    process is in agreement with the first law of thermodynamics. A comparison of the stratification efficiencies obtained from experimental results of charging, standby, and discharging processes gives meaningful insights into the different mixing behaviors of a storage tank that is charged and discharged......A new method for the calculation of a stratification efficiency of thermal energy storages based on the second law of thermodynamics is presented. The biasing influence of heat losses is studied theoretically and experimentally. Theoretically, it does not make a difference if the stratification...

  14. Dividing wall column: Improving thermal efficiency, energy savings and economic performance

    International Nuclear Information System (INIS)

    Aurangzeb, Md; Jana, Amiya K.

    2016-01-01

    Highlights: • A rigorous model is developed for a dividing wall column. • Heat transfer model for metal wall is proposed. • Performance improvement is quantified for a ternary system. • Thermal efficiency, energy savings and cost are three used indices. - Abstract: This work aims at investigating the performance improvement of a dividing wall column (DWC) for the separation of a ternary system. It is true that for fractionating a ternary mixture, at least a sequence of two conventional distillation columns is required. To improve energetic and economic potential, and reduce space requirement, two columns are proposed to merge into one shell with a dividing wall. For developing the mathematical model of a distillation column, we consider the effect of heat transfer through the metal wall placed at an intermediated position inside the cylindrical column. The simulated DWC model is verified using the Aspen Plus flowsheet simulator with a wide variety of phase equilibrium models. The superiority of this proposed heat integrated configuration is shown for a ternary hydrocarbon system over a conventional distillation sequence (CDS) in terms of mainly three performance indexes, namely thermal efficiency, energy savings and total annual cost (TAC). It is investigated that the dividing wall distillation scheme can secure a 37.5% energy efficiency, and a 22.6% savings in energy consumption and 23.23% in TAC. The promising performance can also be quantified in terms of a reasonably low payback period of 2.11 years.

  15. Assessing thermal comfort and energy efficiency in buildings by statistical quality control for autocorrelated data

    International Nuclear Information System (INIS)

    Barbeito, Inés; Zaragoza, Sonia; Tarrío-Saavedra, Javier; Naya, Salvador

    2017-01-01

    Highlights: • Intelligent web platform development for energy efficiency management in buildings. • Controlling and supervising thermal comfort and energy consumption in buildings. • Statistical quality control procedure to deal with autocorrelated data. • Open source alternative using R software. - Abstract: In this paper, a case study of performing a reliable statistical procedure to evaluate the quality of HVAC systems in buildings using data retrieved from an ad hoc big data web energy platform is presented. The proposed methodology based on statistical quality control (SQC) is used to analyze the real state of thermal comfort and energy efficiency of the offices of the company FRIDAMA (Spain) in a reliable way. Non-conformities or alarms, and the actual assignable causes of these out of control states are detected. The capability to meet specification requirements is also analyzed. Tools and packages implemented in the open-source R software are employed to apply the different procedures. First, this study proposes to fit ARIMA time series models to CTQ variables. Then, the application of Shewhart and EWMA control charts to the time series residuals is proposed to control and monitor thermal comfort and energy consumption in buildings. Once thermal comfort and consumption variability are estimated, the implementation of capability indexes for autocorrelated variables is proposed to calculate the degree to which standards specifications are met. According with case study results, the proposed methodology has detected real anomalies in HVAC installation, helping to detect assignable causes and to make appropriate decisions. One of the goals is to perform and describe step by step this statistical procedure in order to be replicated by practitioners in a better way.

  16. Optimization of Thermal Object Nonlinear Control Systems by Energy Efficiency Criterion.

    Science.gov (United States)

    Velichkin, Vladimir A.; Zavyalov, Vladimir A.

    2018-03-01

    This article presents the results of thermal object functioning control analysis (heat exchanger, dryer, heat treatment chamber, etc.). The results were used to determine a mathematical model of the generalized thermal control object. The appropriate optimality criterion was chosen to make the control more energy-efficient. The mathematical programming task was formulated based on the chosen optimality criterion, control object mathematical model and technological constraints. The “maximum energy efficiency” criterion helped avoid solving a system of nonlinear differential equations and solve the formulated problem of mathematical programming in an analytical way. It should be noted that in the case under review the search for optimal control and optimal trajectory reduces to solving an algebraic system of equations. In addition, it is shown that the optimal trajectory does not depend on the dynamic characteristics of the control object.

  17. Thermal dynamic simulation of wall for building energy efficiency under varied climate environment

    Science.gov (United States)

    Wang, Xuejin; Zhang, Yujin; Hong, Jing

    2017-08-01

    Aiming at different kind of walls in five cities of different zoning for thermal design, using thermal instantaneous response factors method, the author develops software to calculation air conditioning cooling load temperature, thermal response factors, and periodic response factors. On the basis of the data, the author gives the net work analysis about the influence of dynamic thermal of wall on air-conditioning load and thermal environment in building of different zoning for thermal design regional, and put forward the strategy how to design thermal insulation and heat preservation wall base on dynamic thermal characteristic of wall under different zoning for thermal design regional. And then provide the theory basis and the technical references for the further study on the heat preservation with the insulation are in the service of energy saving wall design. All-year thermal dynamic load simulating and energy consumption analysis for new energy-saving building is very important in building environment. This software will provide the referable scientific foundation for all-year new thermal dynamic load simulation, energy consumption analysis, building environment systems control, carrying through farther research on thermal particularity and general particularity evaluation for new energy -saving walls building. Based on which, we will not only expediently design system of building energy, but also analyze building energy consumption and carry through scientific energy management. The study will provide the referable scientific foundation for carrying through farther research on thermal particularity and general particularity evaluation for new energy saving walls building.

  18. Integration of solar thermal for improved energy efficiency in low-temperature-pinch industrial processes

    International Nuclear Information System (INIS)

    Atkins, Martin J.; Walmsley, Michael R.W.; Morrison, Andrew S.

    2010-01-01

    Solar thermal systems have the potential to provide renewable industrial process heat and are especially suited for low pinch temperature processes such as those in the food, beverage, and textile sectors. When correctly integrated within an industrial process, they can provide significant progress towards both increased energy efficiency and reduction in emissions. However, the integration of renewable solar energy into industrial processes presents a challenge for existing process integration techniques due to the non-continuous nature of the supply. A thorough pinch analysis study of the industrial process, taking in to account non-continuous operating rates, should be performed to evaluate the utility demand profile. Solar collector efficiency data under variable climatic conditions should also be collected for the specific site. A systematic method of combining this information leads to improved design and an optimal operating strategy. This approach has been applied to a New Zealand milk powder plant and benefits of several integration strategies, including mass integration, are investigated. The appropriate placement of the solar heat is analogous to the placement of a hot utility source and an energy penalty will be incurred when the solar thermal system provides heat below the pinch temperature.

  19. Integration of solar thermal for improved energy efficiency in low-temperature-pinch industrial processes

    Energy Technology Data Exchange (ETDEWEB)

    Atkins, Martin J.; Walmsley, Michael R.W.; Morrison, Andrew S. [Energy Research Group, School of Science and Engineering, University of Waikato, Private Bag 3105, Hamilton 3240 (New Zealand)

    2010-05-15

    Solar thermal systems have the potential to provide renewable industrial process heat and are especially suited for low pinch temperature processes such as those in the food, beverage, and textile sectors. When correctly integrated within an industrial process, they can provide significant progress towards both increased energy efficiency and reduction in emissions. However, the integration of renewable solar energy into industrial processes presents a challenge for existing process integration techniques due to the non-continuous nature of the supply. A thorough pinch analysis study of the industrial process, taking in to account non-continuous operating rates, should be performed to evaluate the utility demand profile. Solar collector efficiency data under variable climatic conditions should also be collected for the specific site. A systematic method of combining this information leads to improved design and an optimal operating strategy. This approach has been applied to a New Zealand milk powder plant and benefits of several integration strategies, including mass integration, are investigated. The appropriate placement of the solar heat is analogous to the placement of a hot utility source and an energy penalty will be incurred when the solar thermal system provides heat below the pinch temperature. (author)

  20. Modernised Portuguese schools - From IAQ and thermal comfort towards energy efficiency plans

    Science.gov (United States)

    Pereira, Luisa Maria Dias

    . The continuous monitoring period varied between schools, from a minimum of 48h monitoring up to three weeks, during the mid-season [spring - autumn period (excluding summer vacation) in 2013]. Air exchange rates (AER), more specifically infiltration rates, are quantified aiming at determining the current airtightness condition of the refurbished schools. A subjective IEQ assessment is also performed, focusing on occupants’ feedback, providing insight on the potential linkages between energy use and occupants’ satisfaction and comfort. The thesis builds on the current EEP panorama and practice, which is based only on cost/energy control, extending it to address the equilibrium between IEQ evaluation and occupants’ perceived conditions/preferences. This approach is applied in two schools - selected based on the previous study on energy and IEQ conditions of the eight schools. The EEP methodology starts by deepening the knowledge of each school, mostly focusing on crossing the schools occupancy schedule with systems operation [(mainly those controlled by the building management system (BMS)]. An analysis on recently updated legislation is also performed (in particular fresh air flow rates requirements). It is shown that some potential energy savings can be achieved and that IEQ conditions can be improved at very low or even negligible costs. Other considerations, namely addressing the thermal energy production systems of the schools (e.g., boilers scheduling), the lighting systems (e.g., lighting circuits) and non-controlled plug loads, are also mentioned. Based upon all these findings, a handbook of good practice is drafted for secondary school buildings in Portugal. This EEP is accompanied by a list of Energy Efficiency Measures (EEM). It is proposed that this document is headed by a School - Energy Performance Certificate (S-EPC) based on the billed energy consumption. This document suggests the establishment of the figure of the Energy Manager.

  1. Evaluation of thermal efficiency and energy conversion of thermoacoustic Stirling engines

    International Nuclear Information System (INIS)

    Zhong Junhu; Zheng Yuli; Qing Li; Qiang Li

    2010-01-01

    Thermodynamic cycle transferring heat and work was executed in thermoacoustic engines, when the acoustic resonators substituted the moving mechanical components of the traditional heat engines. Based on the traveling-wave phasing and reversible heat transfer, thermoacoustic Stirling engines could achieve 70% of the Carnot efficiency theoretically, if the inevitable viscous dissipation in resonators was also counted as exported power. It should be pointed out an error on this efficiency evaluation in the previous literatures. More than 70% of the acoustic power production was often consumed by the side-branch resonator that was the essential configuration to build up a thermoacoustic Stirling engine. According to the simulation results and some experimental data, the actual available acoustic power consumed by the acoustic loads was restricted by the operating peak-to-mean pressure ratio, i.e. |p 1 /p m |. When the peak-to-mean pressure ratio operated on 4-6.5%, the thermal efficiency and power density of the available acoustic power reached higher levels. But the available acoustic power would approach zero when |p 1 /p m | attained 10%. It was approved that the turbulence oscillation occurred on the higher |p 1 /p m | (usually >4%) was the main reason of the excess dissipation in the side-branch resonator. This character of the available power limited the wide application of thermoacoustic Stirling engines. The evaluation of thermal efficiency and energy conversion also indicated the improving direction of thermoacoustic Stirling engines. Generators driven by the thermoacoustic Stirling engines were an effective way, due to the elimination of the side-branch resonator. To achieve a high power density and a high pressure ratio on the higher available power efficiency level, the standing-wave thermoacoustic engines might outvie the traveling-wave thermoacoustic engines. To enjoy the best features of standing-wave engines and traveling-wave engines simultaneously

  2. Total-Factor Energy Efficiency (TFEE Evaluation on Thermal Power Industry with DEA, Malmquist and Multiple Regression Techniques

    Directory of Open Access Journals (Sweden)

    Jin-Peng Liu

    2017-07-01

    Full Text Available Under the background of a new round of power market reform, realizing the goals of energy saving and emission reduction, reducing the coal consumption and ensuring the sustainable development are the key issues for thermal power industry. With the biggest economy and energy consumption scales in the world, China should promote the energy efficiency of thermal power industry to solve these problems. Therefore, from multiple perspectives, the factors influential to the energy efficiency of thermal power industry were identified. Based on the economic, social and environmental factors, a combination model with Data Envelopment Analysis (DEA and Malmquist index was constructed to evaluate the total-factor energy efficiency (TFEE in thermal power industry. With the empirical studies from national and provincial levels, the TFEE index can be factorized into the technical efficiency index (TECH, the technical progress index (TPCH, the pure efficiency index (PECH and the scale efficiency index (SECH. The analysis showed that the TFEE was mainly determined by TECH and PECH. Meanwhile, by panel data regression model, unit coal consumption, talents and government supervision were selected as important indexes to have positive effects on TFEE in thermal power industry. In addition, the negative indexes, such as energy price and installed capacity, were also analyzed to control their undesired effects. Finally, considering the analysis results, measures for improving energy efficiency of thermal power industry were discussed widely, such as strengthening technology research and design (R&D, enforcing pollutant and emission reduction, distributing capital and labor rationally and improving the government supervision. Relative study results and suggestions can provide references for Chinese government and enterprises to enhance the energy efficiency level.

  3. Simulation of Thermal Distribution and Airflow for Efficient Energy Consumption in a Small Data Centers

    Directory of Open Access Journals (Sweden)

    Jing Ni

    2017-04-01

    Full Text Available Data centers have become ubiquitous in the last few years in an attempt to keep pace with the processing and storage needs of the Internet and cloud computing. The steady growth in the heat densities of IT servers leads to a rise in the energy needed to cool them, and constitutes approximately 40% of the power consumed by data centers. However, many data centers feature redundant air conditioning systems that contribute to inefficient air distribution, which significantly increases energy consumption. This remains an insufficiently explored problem. In this paper, a typical, small data center with tiles for an air supply system with a raised floor is used. We use a fluent (Computational Fluid Dynamics, CFD to simulate thermal distribution and airflow, and investigate the optimal conditions of air distribution to save energy. The effects of the airflow outlet angle along the tile, the cooling temperature and the rate of airflow on the beta index as well as the energy utilization index are discussed, and the optimal conditions are obtained. The reasonable airflow distribution achieved using 3D CFD calculations and the parameter settings provided in this paper can help reduce the energy consumption of data centers by improving the efficiency of the air conditioning.

  4. Guidelines for developing efficient thermal conduction and storage models within building energy simulations

    International Nuclear Information System (INIS)

    Hillary, Jason; Walsh, Ed; Shah, Amip; Zhou, Rongliang; Walsh, Pat

    2017-01-01

    Improving building energy efficiency is of paramount importance due to the large proportion of energy consumed by thermal operations. Consequently, simulating a building's environment has gained popularity for assessing thermal comfort and design. The extended timeframes and large physical scales involved necessitate compact modelling approaches. The accuracy of such simulations is of chief concern, yet there is little guidance offered on achieving accurate solutions whilst mitigating prohibitive computational costs. Therefore, the present study addresses this deficit by providing clear guidance on discretisation levels required for achieving accurate but computationally inexpensive models. This is achieved by comparing numerical models of varying discretisation levels to benchmark analytical solutions with prediction accuracy assessed and reported in terms of governing dimensionless parameters, Biot and Fourier numbers, to ensure generality of findings. Furthermore, spatial and temporal discretisation errors are separated and assessed independently. Contour plots are presented to intuitively determine the optimal discretisation levels and time-steps required to achieve accurate thermal response predictions. Simulations derived from these contour plots were tested against various building conditions with excellent agreement observed throughout. Additionally, various scenarios are highlighted where the classical single lumped capacitance model can be applied for Biot numbers much greater than 0.1 without reducing accuracy. - Highlights: • Addressing the problems of inadequate discretisation within building energy models. • Accuracy of numerical models assessed against analytical solutions. • Fourier and Biot numbers used to provide generality of results for any material. • Contour plots offer intuitive way to interpret results for manual discretisation. • Results show proposed technique promising for automation of discretisation process.

  5. Investigation of the charge boost technology for the efficiency increase of closed sorption thermal energy storage systems

    Science.gov (United States)

    Rohringer, C.; Engel, G.; Köll, R.; Wagner, W.; van Helden, W.

    2017-10-01

    The inclusion of solar thermal energy into energy systems requires storage possibilities to overcome the gap between supply and demand. Storage of thermal energy with closed sorption thermal energy systems has the advantage of low thermal losses and high energy density. However, the efficiency of these systems needs yet to be increased to become competitive on the market. In this paper, the so-called “charge boost technology” is developed and tested via experiments as a new concept for the efficiency increase of compact thermal energy storages. The main benefit of the charge boost technology is that it can reach a defined state of charge for sorption thermal energy storages at lower temperature levels than classic pure desorption processes. Experiments are conducted to provide a proof of principle for this concept. The results show that the charge boost technology does function as predicted and is a viable option for further improvement of sorption thermal energy storages. Subsequently, a new process application is developed by the author with strong focus on the utilization of the advantages of the charge boost technology over conventional desorption processes. After completion of the conceptual design, the theoretical calculations are validated via experiments.

  6. Sensitivity analysis of efficiency thermal energy storage on selected rock mass and grout parameters using design of experiment method

    International Nuclear Information System (INIS)

    Wołoszyn, Jerzy; Gołaś, Andrzej

    2014-01-01

    Highlights: • Paper propose a new methodology to sensitivity study of underground thermal storage. • Using MDF model and DOE technique significantly shorter of calculations time. • Calculation of one time step was equal to approximately 57 s. • Sensitivity study cover five thermo-physical parameters. • Conductivity of rock mass and grout material have a significant impact on efficiency. - Abstract: The aim of this study was to investigate the influence of selected parameters on the efficiency of underground thermal energy storage. In this paper, besides thermal conductivity, the effect of such parameters as specific heat, density of the rock mass, thermal conductivity and specific heat of grout material was investigated. Implementation of this objective requires the use of an efficient computational method. The aim of the research was achieved by using a new numerical model, Multi Degree of Freedom (MDF), as developed by the authors and Design of Experiment (DoE) techniques with a response surface. The presented methodology can significantly reduce the time that is needed for research and to determine the effect of various parameters on the efficiency of underground thermal energy storage. Preliminary results of the research confirmed that thermal conductivity of the rock mass has the greatest impact on the efficiency of underground thermal energy storage, and that other parameters also play quite significant role

  7. The use of salinity contrast for density difference compensation to improve the thermal recovery efficiency in high-temperature aquifer thermal energy storage systems

    NARCIS (Netherlands)

    van Lopik, J.H.; Hartog, N.; Zaadnoordijk, Willem Jan

    The efficiency of heat recovery in high-temperature (>60 °C) aquifer thermal energy storage (HT-ATES) systems is limited due to the buoyancy of the injected hot water. This study investigates the potential to improve the efficiency through compensation of the density difference by increased salinity

  8. Energy efficiency

    International Nuclear Information System (INIS)

    Marvillet, Ch.; Tochon, P.; Mercier, P.

    2004-01-01

    World energy demand is constantly rising. This is a legitimate trend, insofar as access to energy enables enhanced quality of life and sanitation levels for populations. On the other hand, such increased consumption generates effects that may be catastrophic for the future of the planet (climate change, environmental imbalance), should this growth conform to the patterns followed, up to recent times, by most industrialized countries. Reduction of greenhouse gas emissions, development of new energy sources and energy efficiency are seen as the major challenges to be taken up for the world of tomorrow. In France, the National Energy Debate indeed emphasized, in 2003, the requirement to control both demand for, and offer of, energy, through a strategic orientation law for energy. The French position corresponds to a slightly singular situation - and a privileged one, compared to other countries - owing to massive use of nuclear power for electricity generation. This option allows France to be responsible for a mere 2% of worldwide greenhouse gas emissions. Real advances can nonetheless still be achieved as regards improved energy efficiency, particularly in the transportation and residential-tertiary sectors, following the lead, in this respect, shown by industry. These two sectors indeed account for over half of the country CO 2 emissions (26% and 25% respectively). With respect to transportation, the work carried out by CEA on the hydrogen pathway, energy converters, and electricity storage has been covered by the preceding chapters. As regards housing, a topic addressed by one of the papers in this chapter, investigations at CEA concern integration of the various devices enabling value-added use of renewable energies. At the same time, the organization is carrying through its activity in the extensive area of heat exchangers, allowing industry to benefit from improved understanding in the modeling of flows. An activity evidenced by advances in energy efficiency for

  9. Improvement of Energy Efficiency and Environmental Safety of Thermal Energy Through the Implementation of Contact Energy Exchange Processes

    Science.gov (United States)

    Varlamov, Gennadii Borysovich; Romanova, Kateryna Alexandrovna; Nazarova, Iryna; Daschenko, Olga; Kapustiansky, Andry

    2017-12-01

    Energy efficiency improvement and ecological safety of heat power plants are urgent problems, which require scientifically grounded approaches and solutions. These problems can be solved partly within the presented heat-and-power cycles by including contact energy exchange equipment in the circuits of existing installations. A significant positive effect is obtained in the contact energy exchange installations, such as gas-steam installation `Aquarius' and the contact hydrogen heat generator that also can use hydrogen as a fuel. In these plants, the efficiency increases approximately by 10-12% in comparison with traditional installations, and the concentration of toxic substances, such as nitrogen oxides and carbon monoxide in flue gas can be reduced to 30 mg/m3 and to 5 mg/m3, respectively. Moreover, the plants additionally `generate' the clean water, which can be used for technical purposes.

  10. Energy efficiency and comfort conditions in passive solar buildings: Effect of thermal mass at equatorial high altitudes

    Science.gov (United States)

    Ogoli, David Mwale

    This dissertation is based on the philosophy that architectural design should not just be a function of aesthetics, but also of energy-efficiency, advanced technologies and passive solar strategies. A lot of published literature is silent regarding buildings in equatorial highland regions. This dissertation is part of the body of knowledge that attempts to provide a study of energy in buildings using thermal mass. The objectives were to establish (1) effect of equatorial high-altitude climate on thermal mass, (2) effect of thermal mass on moderating indoor temperatures, (3) effect of thermal mass in reducing heating and cooling energy, and (4) the amount of time lag and decrement factor of thermal mass. Evidence to analyze the effect of thermal mass issues came from three sources. First, experimental physical models involving four houses were parametrically conducted in Nairobi, Kenya. Second, energy computations were made using variations in thermal mass for determining annual energy usage and costs. Third, the data gathered were observed, evaluated, and compared with currently published research. The findings showed that: (1) Equatorial high-altitude climates that have diurnal temperature ranging about 10--15°C allow thermal mass to moderate indoor temperatures; (2) Several equations were established that indicate that indoor mean radiant temperatures can be predicted from outdoor temperatures; (3) Thermal mass can reduce annual energy for heating and cooling by about 71%; (4) Time lag and decrement of 200mm thick stone and concrete thermal mass can be predicted by a new formula; (5) All windows on a building should be shaded. East and west windows when shaded save 51% of the cooling energy. North and south windows when fully shaded account for a further 26% of the cooling energy; (6) Insulation on the outside of a wall reduces energy use by about 19.6% below the levels with insulation on the inside. The basic premise of this dissertation is that decisions that

  11. Assessing energy efficiency of electric car bottom furnaces intended for thermal energization of minerals

    Science.gov (United States)

    Nizhegorodov, A. I.

    2017-01-01

    The paper deals with a new concept of electric furnaces for roasting and thermal energization of vermiculite and other minerals with vibrational transportation of a single-layer mass under constant thermal field. The paper presents performance calculation and comparative assessment of energy data for furnaces of different modifications: flame and electric furnaces with three units, furnaces with six units and ones with series-parallel connection of units, and furnaces of new concept.

  12. Energy efficiency and indoor thermal perception. A comparative study between radiant panel and portable convective heaters

    Energy Technology Data Exchange (ETDEWEB)

    Ali, Ahmed Hamza H.; Morsy, Mahmoud Gaber [Department of Mechanical Engineering, Faculty of Engineering, Assiut University, Assiut, 71516 (Egypt)

    2010-11-15

    This study investigates experimentally the thermal perception of indoor environment for evaluating the ability of radiant panel heaters to produce thermal comfort for space occupants as well as the energy consumption in comparison with conventional portable natural convective heaters. The thermal perception results show that, compared with conventional convection heater, a radiantly heated office room maintains a lower ambient air temperature while providing equal levels of thermal perception on the thermal dummy head as the convective heater and saves up to 39.1% of the energy consumption per day. However, for human subjects' vote experiments, the results show that for an environmentally controlled test room at outdoor environment temperatures of 0C and 5C, using two radiant panel heaters with a total capacity of 580 W leads to a better comfort sensation than the conventional portable natural convective heater with a 670 W capacity, with an energy saving of about 13.4%. In addition, for an outdoor environment temperature of 10C, using one radiant panel heater with a capacity of 290 W leads to a better comfort sensation than the conventional convection heater with a 670 W capacity, with an energy saving of about 56.7%. From the analytical results, it is found that distributing the radiant panel heater inside the office room, one on the wall facing the window and the other on the wall close to the window, provides the best operative temperature distribution within the room.

  13. Clock Gating Based Energy Efficient and Thermal Aware Design of Latin Unicode Reader for Natural Language Processing on FPGA

    DEFF Research Database (Denmark)

    Singh, Ritu; Kalia, Kartik; Minver, M. H.

    2016-01-01

    Abstract-In this paper we have aimed to design an energy efficient and thermally aware Latin Unicode Reader. Our design is based on 28nm FPGA (Kintex-7) and 40nm FPGA (Artix-7). In order to test the portability of our design, we are operating our design with respective frequency of different mobile...

  14. Does environmental regulation affect energy efficiency in China's thermal power generation? Empirical evidence from a slacks-based DEA model

    International Nuclear Information System (INIS)

    Bi, Gong-Bing; Song, Wen; Zhou, P.; Liang, Liang

    2014-01-01

    Data envelopment analysis (DEA) has gained much popularity in performance measurement of power industry. This paper presents a slack-based measure approach to investigating the relationship between fossil fuel consumption and the environmental regulation of China's thermal power generation. We first calculate the total-factor energy efficiency without considering environmental constraints. An environmental performance indicator is proposed through decomposing the total-factor energy efficiency. The proposed approach is then employed to examine whether environmental regulation affects the energy efficiency of China's thermal power generation. We find that the environmental efficiency plays a significant role in affecting energy performance of China's thermal generation sector. Decreasing the discharge of major pollutants can improve both energy performance and environmental efficiency. Besides, we also have three main findings: (1) The energy efficiency and environmental efficiency were relatively low. (2) The energy and environmental efficiency scores show great variations among provinces. (3) Both energy efficiency and environmental efficiency are of obvious geographical characteristics. According to our findings, we suggest some policy implications. - Highlights: • We assess the energy efficiency and the environmental efficiency of China's thermal power generation simultaneously. • The energy efficiency and the environmental efficiency were relatively low during 2007–2009. • The energy efficiency and environmental efficiency show obvious geographic characters. • The environmental performance of a DMU plays a decisive role in the energy performance

  15. Investigation of Different Configurations of a Ventilated Window to Optimize Both Energy Efficiency and Thermal Comfort

    DEFF Research Database (Denmark)

    Liu, Mingzhe; Heiselberg, Per; Larsen, Olena Kalyanova

    2017-01-01

    on thermal comfort. Hourly simulations of the heat balances of the windows are conducted on four days representing different typical weather conditions according to the method described in EN ISO 13790. Uand g values used in the calculation method are calculated in European software tool (WIS......) for the calculation of the thermal and solar properties of commercial and innovative window systems. Additionally, comfort performance is evaluated by inlet air temperature and internal surface temperature of the windows calculated by WIS software. The results of the study show the energy and comfort performance...... the energy consumption or optimizing the thermal comfort. The provided optimal window typologies can be used in residential and commercial buildings for both new constructions and renovations....

  16. Investigation of Different Configurations of a Ventilated Window to Optimize Both Energy Efficiency and Thermal Comfort

    DEFF Research Database (Denmark)

    Liu, Mingzhe; Heiselberg, Per; Larsen, Olena Kalyanova

    2017-01-01

    on thermal comfort. Hourly simulations of the heat balances of the windows are conducted on four days representing different typical weather conditions according to the method described in EN ISO 13790. U and g values used in the calculation method are calculated in European software tool (WIS......) for the calculation of the thermal and solar properties of commercial and innovative window systems. Additionally, comfort performance is evaluated by inlet air temperature and internal surface temperature of the windows calculated by WIS software. The results of the study show the energy and comfort performance...... the energy consumption or optimizing the thermal comfort. The provided optimal window typologies can be used in residential and commercial buildings for both new constructions and renovations....

  17. Hierarchically interconnected porous scaffolds for phase change materials with improved thermal conductivity and efficient solar-to-electric energy conversion.

    Science.gov (United States)

    Yang, Jie; Yu, Peng; Tang, Li-Sheng; Bao, Rui-Ying; Liu, Zheng-Ying; Yang, Ming-Bo; Yang, Wei

    2017-11-23

    An ice-templating self-assembly strategy and a vacuum impregnation method were used to fabricate polyethylene glycol (PEG)/hierarchical porous scaffold composite phase change materials (PCMs). Hierarchically interconnected porous scaffolds of boron nitride (BN), with the aid of a small amount of graphene oxide (GO), endow the composite PCMs with high thermal conductivity, excellent shape-stability and efficient solar-to-electric energy conversion. The formation of a three-dimensional (3D) thermally conductive pathway in the composites contributes to improving the thermal conductivity up to 2.36 W m -1 K -1 at a relatively low content of BN (ca. 23 wt%). This work provides a route for thermally conductive and shape-stabilized composite PCMs used as energy storage materials.

  18. High efficiency direct thermal to electric energy conversion from radioisotope decay using selective emitters and spectrally tuned solar cells

    Science.gov (United States)

    Chubb, Donald L.; Flood, Dennis J.; Lowe, Roland A.

    1993-01-01

    Thermophotovoltaic (TPV) systems are attractive possibilities for direct thermal-to-electric energy conversion, but have typically required the use of black body radiators operating at high temperatures. Recent advances in both the understanding and performance of solid rare-earth oxide selective emitters make possible the use of TPV at temperatures as low as 1200K. Both selective emitter and filter system TPV systems are feasible. However, requirements on the filter system are severe in order to attain high efficiency. A thin-film of a rare-earth oxide is one method for producing an efficient, rugged selective emitter. An efficiency of 0.14 and power density of 9.2 W/KG at 1200K is calculated for a hypothetical thin-film neodymia (Nd2O3) selective emitter TPV system that uses radioisotope decay as the thermal energy source.

  19. High efficiency direct thermal to electric energy conversion from radioisotope decay using selective emitters and spectrally tuned solar cells

    International Nuclear Information System (INIS)

    Chubb, D.L.; Flood, D.J.; Lowe, R.A.

    1993-08-01

    Thermophotovoltaic (TPV) systems are attractive possibilities for direct thermal-to-electric energy conversion, but have typically required the use of black body radiators operating at high temperatures. Recent advances in both the understanding and performance of solid rare-earth oxide selective emitters make possible the use of TPV at temperatures as low as 1200K. Both selective emitter and filter system TPV systems are feasible. However, requirements on the filter system are severe in order to attain high efficiency. A thin-film of a rare-earth oxide is one method for producing an efficient, rugged selective emitter. An efficiency of 0.14 and power density of 9.2 W/KG at 1200K is calculated for a hypothetical thin-film neodymia (Nd2O3) selective emitter TPV system that uses radioisotope decay as the thermal energy source

  20. Coal consumption minimizing by increasing thermal energy efficiency at ROMAG-PROD Heavy Water Plant

    International Nuclear Information System (INIS)

    Preda, Marius Cristian

    2006-01-01

    ROMAG-PROD Heavy Water Plant is a large thermal energy consumer using almost all the steam output from ROMAG-TERMO Power Plant - the steam cost weight in the total heavy water price is about 40%. The steam consumption minimizing by modernization of isotopic exchange facilities and engineering development in ROMAG-PROD Heavy Water Plant results in an corresponding decrease of coal amount burned at ROMAG-TERMO boilers. This decrease could be achieved mainly by the followings ways: - Facility wrappings integrity; - High performance heat exchangers; - Refurbished heat insulations; - Modified condenser-collecting pipeline routes; - High performance steam traps; - Heat electric wire. When coal is burned in Power Plant burners to obtain thermal energy, toxic emissions results in flue gases, such as: - CO 2 and NO x with impact on climate warming; - SO 2 which results in ozone layer thinning effect and in acid rain falls. From the value of steam output per burned coal: 1 GCal steam = 1.41 tone steam = 0.86 thermal MW = 1.1911 tones burned coal (lignite), it is obvious that by decreasing the thermal energy consumption provided for ROMAG PROD, a coal amount decrease is estimated at about 45 t/h, or about 394,200 t/year coal, which means about 10% of the current coal consumption at ROMAG-TERMO PP. At the same time, by reducing the burned coal amount, an yearly decrease in emissions into air to about 400,000 tones CO 2 is expected

  1. Energy efficiency improvement procedures and audit results of electrical, thermal and solar applications in Palestine

    International Nuclear Information System (INIS)

    Ibrik, I.H.; Mahmoud, M.M.

    2005-01-01

    Energy conservation in utilities has played a vital role in improving energy efficiency in the industrial, commercial and residential sectors. The electrical energy consumption in Palestine has increased sharply in the past few years and achieved by the end of 2001 to 10% per year. It is expected that this percentage will increase to about 12% if the current political situation will end hopefully with peace. Modern energy efficient technologies are needed for the national energy policy. Such technologies are investigated in this paper. Implementing of a national 3 years project aiming at energy efficiency improvement in residential and industrial sectors as well as in public utilities, which include wide range of diversified audits and power measurements, had led to creating this paper. Measurement and audit results had shown that the total conservation potential in these sectors is around 15% of the total energy consumption. The associated costs of the investment in this field are relatively low and correspond to a pay back period varying in the range from 6 to 36 months. Consequently, the energy conservation policy will be seriously improved in the forthcoming years. It is estimated that 10% of the new energy purchasing capacity will be reduced accordingly

  2. Investigation of Different Configurations of a Ventilated Window to Optimize Both Energy Efficiency and Thermal Comfort

    DEFF Research Database (Denmark)

    Liu, Mingzhe; Heiselberg, Per; Larsen, Olena Kalyanova

    2017-01-01

    The study in this article investigates 15 ventilated window typologies with different pane configurations and glazing types in climates of four European countries (United Kingdom, Denmark, France and Germany) in order to identify the optimum typology with regard to their energy balance and impact...... on thermal comfort. Hourly simulations of the heat balances of the windows are conducted on four days representing different typical weather conditions according to the method described in EN ISO 13790. U and g values used in the calculation method are calculated in European software tool (WIS......) for the calculation of the thermal and solar properties of commercial and innovative window systems. Additionally, comfort performance is evaluated by inlet air temperature and internal surface temperature of the windows calculated by WIS software. The results of the study show the energy and comfort performance...

  3. Development of a thermal control algorithm using artificial neural network models for improved thermal comfort and energy efficiency in accommodation buildings

    International Nuclear Information System (INIS)

    Moon, Jin Woo; Jung, Sung Kwon

    2016-01-01

    Highlights: • An ANN model for predicting optimal start moment of the cooling system was developed. • An ANN model for predicting the amount of cooling energy consumption was developed. • An optimal control algorithm was developed employing two ANN models. • The algorithm showed the advanced thermal comfort and energy efficiency. - Abstract: The aim of this study was to develop a control algorithm to demonstrate the improved thermal comfort and building energy efficiency of accommodation buildings in the cooling season. For this, two artificial neural network (ANN)-based predictive and adaptive models were developed and employed in the algorithm. One model predicted the cooling energy consumption during the unoccupied period for different setback temperatures and the other predicted the time required for restoring current indoor temperature to the normal set-point temperature. Using numerical simulation methods, the prediction accuracy of the two ANN models and the performance of the algorithm were tested. Through the test result analysis, the two ANN models showed their prediction accuracy with an acceptable error rate when applied in the control algorithm. In addition, the two ANN models based algorithm can be used to provide a more comfortable and energy efficient indoor thermal environment than the two conventional control methods, which respectively employed a fixed set-point temperature for the entire day and a setback temperature during the unoccupied period. Therefore, the operating range was 23–26 °C during the occupied period and 25–28 °C during the unoccupied period. Based on the analysis, it can be concluded that the optimal algorithm with two predictive and adaptive ANN models can be used to design a more comfortable and energy efficient indoor thermal environment for accommodation buildings in a comprehensive manner.

  4. A Building Energy Efficiency Optimization Method by Evaluating the Effective Thermal Zones Occupancy

    Directory of Open Access Journals (Sweden)

    Franco Cotana

    2012-12-01

    Full Text Available Building energy efficiency is strongly linked to the operations and control systems, together with the integrated performance of passive and active systems. In new high quality buildings in particular, where these two latter aspects have been already implemented at the design stage, users’ perspective, obtained through post-occupancy assessment, has to be considered to reduce whole energy requirement during service life. This research presents an innovative and low-cost methodology to reduce buildings’ energy requirements through post-occupancy assessment and optimization of energy operations using effective users’ attitudes and requirements as feedback. As a meaningful example, the proposed method is applied to a multipurpose building located in New York City, NY, USA, where real occupancy conditions are assessed. The effectiveness of the method is tested through dynamic simulations using a numerical model of the case study, calibrated through real monitoring data collected on the building. Results show that, for the chosen case study, the method provides optimized building energy operations which allow a reduction of primary energy requirements for HVAC, lighting, room-electricity, and auxiliary supply by about 21%. This paper shows that the proposed strategy represents an effective way to reduce buildings’ energy waste, in particular in those complex and high-efficiency buildings that are not performing as well as expected during the concept-design-commissioning stage, in particular due to the lack of feedback after the building handover.

  5. A functional form-stable phase change composite with high efficiency electro-to-thermal energy conversion

    International Nuclear Information System (INIS)

    Wu, Wenhao; Huang, Xinyu; Li, Kai; Yao, Ruimin; Chen, Renjie; Zou, Ruqiang

    2017-01-01

    Graphical abstract: The thermal conductivity of PU was enhanced to 43 times of the pristine value by encapsulation in a PGF, PU@PGF can be used for highly efficient electro-to-heat energy conversion and storage with the highest energy storage efficiency up to 85%. - Highlights: • The composite exhibits an in-situ solid-solid phase change behavior. • The enthalpy of polyurethane is enhanced within the matrix. • The thermal conductivity of the composite is 43 times as much as that of the polyurethane. • Supercooling of polyurethane is greatly reduced. • The composite is applied to cold protection as a wear layer. - Abstract: A novel solid-to-solid phase change composite brick was prepared by combination of polyurethane (PU) and pitch-based graphite foam (PGF). The carbonaceous support, which can be used for mass production, not only greatly improves the thermal conductivity but promote electro-to-heat conversion efficiency of organic phase change materials (PCMs). Our composite retained the enthalpy of PCM and exhibited a greatly reduced supercooling temperature. The novel composite was investigated by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and scanning electron microscope (SEM). The enthalpy of polyurethane has increased about 8.6% after infiltrating into graphite foam. The composite was very stable during thermal cycle test, and the electro-to-heat conversion efficiency achieves to 85% at lower voltages (1.5–1.8 V), which can vastly reduce energy consumption. The as-prepared composite was used in a wear layer to test its performance comparing with normal fabric.

  6. Analysis of recovery efficiency in high-temperature aquifer thermal energy storage: a Rayleigh-based method

    Science.gov (United States)

    Schout, Gilian; Drijver, Benno; Gutierrez-Neri, Mariene; Schotting, Ruud

    2014-01-01

    High-temperature aquifer thermal energy storage (HT-ATES) is an important technique for energy conservation. A controlling factor for the economic feasibility of HT-ATES is the recovery efficiency. Due to the effects of density-driven flow (free convection), HT-ATES systems applied in permeable aquifers typically have lower recovery efficiencies than conventional (low-temperature) ATES systems. For a reliable estimation of the recovery efficiency it is, therefore, important to take the effect of density-driven flow into account. A numerical evaluation of the prime factors influencing the recovery efficiency of HT-ATES systems is presented. Sensitivity runs evaluating the effects of aquifer properties, as well as operational variables, were performed to deduce the most important factors that control the recovery efficiency. A correlation was found between the dimensionless Rayleigh number (a measure of the relative strength of free convection) and the calculated recovery efficiencies. Based on a modified Rayleigh number, two simple analytical solutions are proposed to calculate the recovery efficiency, each one covering a different range of aquifer thicknesses. The analytical solutions accurately reproduce all numerically modeled scenarios with an average error of less than 3 %. The proposed method can be of practical use when considering or designing an HT-ATES system.

  7. Energy Efficiency

    DEFF Research Database (Denmark)

    Petrichenko, Ksenia; Farrell, Timothy Clifford; Thorsch Krader, Thomas

    2016-01-01

    This report was commissioned by REN21 and produced in collaboration with a global network of research partners. Financing was provided by the German Federal Ministry for Economic Cooperation and Development (BMZ), the German Federal Ministry for Economic Affairs and Energy (BMWi), the Government...

  8. Energy Efficiency

    OpenAIRE

    Petrichenko, Ksenia; Farrell, Timothy Clifford; Thorsch Krader, Thomas; Tsakiris, Aristeidis

    2016-01-01

    This report was commissioned by REN21 and produced in collaboration with a global network of research partners. Financing was provided by the German Federal Ministry for Economic Cooperation and Development (BMZ), the German Federal Ministry for Economic Affairs and Energy (BMWi), the Government of South Africa, the Inter-American Development Bank (IDB), the United Nations Environment Programme (UNEP) and the World Bank Group. A large share of the research for this report was conducted on a v...

  9. Thermal cooling using low-temperature waste heat. A cost-effective way for industrial companies to improve energy efficiency?

    Energy Technology Data Exchange (ETDEWEB)

    Schall, D.; Hirzel, S. [Fraunhofer Institute for Systems and Innovation Research ISI, Breslauer Strasse 48, 76139 Karlsruhe (Germany)

    2012-11-15

    As a typical cross-cutting technology, cooling and refrigeration equipment is used for a variety of industrial applications. While cooling is often provided by electric compression cooling systems, thermal cooling systems powered by low-temperature waste heat could improve energy efficiency and promise a technical saving potential corresponding to 0.5 % of the total electricity demand in the German industry. In this paper, we investigate the current and future cost-effectiveness of thermal cooling systems for industrial companies. Our focus is on single-stage, closed absorption and adsorption cooling systems with cooling powers between 40 and 100 kW, which use low-temperature waste heat at temperature levels between 70C and 85C. We analyse the current and future cost-effectiveness of these alternative cooling systems using annual cooling costs (annuities) and payback times. For a forecast until 2015, we apply the concept of experience curves, identifying learning rates of 14 % (absorption machines) and 17 % (adsorption machines) by an expert survey of the German market. The results indicate that thermal cooling systems are currently only cost-effective under optimistic assumptions (full-time operation, high electricity prices) when compared to electric compression cooling systems. Nevertheless, the cost and efficiency improvements expected for this still young technology mean that thermal cooling systems could be more cost-effective in the future. However, depending on future electricity prices, a high number of operating hours is still crucial to achieve payback times substantially below 4 years which are usually required for energy efficiency measures to be widely adopted in the industry.

  10. Energy Efficient Thermal Management for Natural Gas Engine Aftertreatment via Active Flow Control

    Energy Technology Data Exchange (ETDEWEB)

    David K. Irick; Ke Nguyen; Vitacheslav Naoumov; Doug Ferguson

    2006-04-01

    The project is focused on the development of an energy efficient aftertreatment system capable of reducing NOx and methane by 90% from lean-burn natural gas engines by applying active exhaust flow control. Compared to conventional passive flow-through reactors, the proposed scheme cuts supplemental energy by 50%-70%. The system consists of a Lean NOx Trap (LNT) system and an oxidation catalyst. Through alternating flow control, a major amount of engine exhaust flows through a large portion of the LNT system in the absorption mode, while a small amount of exhaust goes through a small portion of the LNT system in the regeneration or desulfurization mode. By periodically reversing the exhaust gas flow through the oxidation catalyst, a higher temperature profile is maintained in the catalyst bed resulting in greater efficiency of the oxidation catalyst at lower exhaust temperatures. The project involves conceptual design, theoretical analysis, computer simulation, prototype fabrication, and empirical studies. This report details the progress during the first twelve months of the project. The primary activities have been to develop the bench flow reactor system, develop the computer simulation and modeling of the reverse-flow oxidation catalyst, install the engine into the test cell, and begin design of the LNT system.

  11. Recent developments in thermally-driven seawater desalination: Energy efficiency improvement by hybridization of the MED and AD cycles

    KAUST Repository

    Ng, Kim Choon

    2015-01-01

    The energy, water and environment nexus is a crucial factor when considering the future development of desalination plants or industry in the water-stressed economies. New generation of desalination processes or plants has to meet the stringent environment discharge requirements and yet the industry remains highly energy efficient and sustainable when producing good potable water. Water sources, either brackish or seawater, have become more contaminated as feed while the demand for desalination capacities increase around the world. One immediate solution for energy efficiency improvement comes from the hybridization of the proven desalination processes to the newer processes of desalination: For example, the integration of the available thermally-driven to adsorption desalination (AD) cycles where significant thermodynamic synergy can be attained when cycles are combined. For these hybrid cycles, a quantum improvement in energy efficiency as well as in increase in water production can be expected. The advent of MED with AD cycles, or simply called the MEDAD cycles, is one such example where seawater desalination can be pursued and operated in cogeneration with the electricity production plants: The hybrid desalination cycles utilize only the low exergy bled-steam at low temperatures, complemented with waste exhaust or renewable solar thermal heat at temperatures between 60 and 80. °C. In this paper, the authors have reported their pioneered research on aspects of AD and related hybrid MEDAD cycles, both at theoretical models and experimental pilots. Using the cogeneration of electricity and desalination concept, the authors examined the cost apportionment of fuel cost by the quality or exergy of working steam for such cogeneration configurations.

  12. The improvement of thermal characteristics of autoclave aerated concrete for energy efficient high-rise buildings application

    Science.gov (United States)

    Khavanov, Pavel; Fomina, Ekaterina; Kozhukhova, Natalia

    2018-03-01

    Nowadays, the problem of energy saving is very relevant. One of the ways to reduction energy consumption in construction materials production and construction of civil and industrial high-rise buildings is the application of claddings with heat-insulating performance. The concept of energy efficiency of high-rise buildings is closely related to environmental aspect and sustainability of applied construction materials; reducing service costs; energy saving and microclimate comfortability. A complexity of architectural and structural design as well as aesthetic characteristics of construction materials are also should be considered. The high interest focused on materials with combined properties. This work is oriented on the study of energy efficiency of buildings by improving heat-insulation and strength performance of autoclave aerated concrete. The applied method of sulfate activation of lime allows monitoring phase and structure formation in aerated concrete. The optimal mix design of aerated concrete with the compressive strength up to 8.5 MPa and decreased density up to 760 kg/m3 was proposed. Analysis of structure at macro-and microscale was performed as well as the criteria of an optimal porosity formation was considered a number, size, shape of pore and density of interior partition. SEM analysis and BET method were performed in this research work. The research results demonstrated the correlation between structure and vapor permeability resistance, also it was found that the increase of strength can lead to reduction of thermal conductivity.

  13. Applying a novel extra-low temperature dedicated outdoor air system in office buildings for energy efficiency and thermal comfort

    International Nuclear Information System (INIS)

    Li, Han; Lee, W.L.; Jia, Jie

    2016-01-01

    Highlights: • A novel dedicated outdoor air system was proposed and investigated. • The proposed system adopts extra-low temperature outdoor air for space cooling. • The extra-low temperature air was generated by a multi-stage direct expansion coil. • Heat pipe was added to the proposed system to recover the waste cooling energy. • Energy and exergy analysis as well as thermal comfort analysis were conducted. - Abstract: A novel dedicated outdoor air system consisting of a multi-stage direct expansion coil and a zero-energy heat pipe to generate extra-low temperature outdoor air to avoid moisture-related problems was proposed in this study. The proposed system’s performance in achieving the desirable air conditions and better energy efficiency objectives is compared with a conventional direct expansion system for air-conditioning of a typical office building in Hong Kong based on simulation investigations. The simulations were carried out using equipment performance data of a pilot study, and realistic building and system characteristics. It was found that the proposed system, as compared to the conventional system, could reduce the annual indoor discomfort hours by 69.4%. An energy and exergy analysis was also conducted. It was revealed that the proposed system could reduce the annual air-conditioning energy use by 15.6% and the system exergy loss rate by 13.6%. The associated overall exergy efficiency was also found 18.6% higher. The findings of this study confirm that the proposed system is better than the conventional system in terms of both energy and exergy efficiency and the desirable air conditions.

  14. Application of multiple-point geostatistics to simulate the effect of small-scale aquifer heterogeneity on the efficiency of aquifer thermal energy storage

    Science.gov (United States)

    Possemiers, Mathias; Huysmans, Marijke; Batelaan, Okke

    2015-08-01

    Adequate aquifer characterization and simulation using heat transport models are indispensible for determining the optimal design for aquifer thermal energy storage (ATES) systems and wells. Recent model studies indicate that meter-scale heterogeneities in the hydraulic conductivity field introduce a considerable uncertainty in the distribution of thermal energy around an ATES system and can lead to a reduction in the thermal recoverability. In a study site in Bierbeek, Belgium, the influence of centimeter-scale clay drapes on the efficiency of a doublet ATES system and the distribution of the thermal energy around the ATES wells are quantified. Multiple-point geostatistical simulation of edge properties is used to incorporate the clay drapes in the models. The results show that clay drapes have an influence both on the distribution of thermal energy in the subsurface and on the efficiency of the ATES system. The distribution of the thermal energy is determined by the strike of the clay drapes, with the major axis of anisotropy parallel to the clay drape strike. The clay drapes have a negative impact (3.3-3.6 %) on the energy output in the models without a hydraulic gradient. In the models with a hydraulic gradient, however, the presence of clay drapes has a positive influence (1.6-10.2 %) on the energy output of the ATES system. It is concluded that it is important to incorporate small-scale heterogeneities in heat transport models to get a better estimate on ATES efficiency and distribution of thermal energy.

  15. Application of multiple-point geostatistics to simulate the effect of small scale aquifer heterogeneity on the efficiency of Aquifer Thermal Energy Storage (ATES)

    Science.gov (United States)

    Possemiers, Mathias; Huysmans, Marijke; Batelaan, Okke

    2015-04-01

    Adequate aquifer characterization and simulation using heat transport models are indispensible for determining the optimal design for Aquifer Thermal Energy Storage (ATES) systems and wells. Recent model studies indicate that meter scale heterogeneities in the hydraulic conductivity field introduce a considerable uncertainty in the distribution of thermal energy around an ATES system and can lead to a reduction in the thermal recoverability. In this paper, the influence of centimeter scale clay drapes on the efficiency of a doublet ATES system and the distribution of the thermal energy around the ATES wells are quantified. Multiple-point geostatistical simulation of edge properties is used to incorporate the clay drapes in the models. The results show that clay drapes have an influence both on the distribution of thermal energy in the subsurface and on the efficiency of the ATES system. The distribution of the thermal energy is determined by the strike of the clay drapes, with the major axis of anisotropy parallel to the clay drape strike. The clay drapes have a negative impact (3.3 - 3.6%) on the energy output in the models without a hydraulic gradient. In the models with a hydraulic gradient, however, the presence of clay drapes has a positive influence (1.6 - 10.2%) on the energy output of the ATES system. It is concluded that it is important to incorporate small scale heterogeneities in heat transport models to get a better estimate on ATES efficiency and distribution of thermal energy.

  16. Comparative analysis of possibilities for raising the efficiency in thermal power plant by utilisation of waste heat energy

    Directory of Open Access Journals (Sweden)

    Mijakovski Vladimir

    2016-01-01

    Full Text Available The possibility to use flue gases waste heat for increasing the efficiency of thermal power plant (TPP explained in this work refers to lignite fired TPP-Bitola in Macedonia (3x233 MW installed electric capacity. Possibility to utilize low-temperature heat energy at the plant’s cold end is also considered in the analysis. Specific fuel consumption is used as an analysis and comparison parameter. Its reduction, compared to the basic power unit ranges between 0.4% and 3.4%. An analysis presenting economic feasibility of the low-temperature heat energy utilization concept for two different refrigerants used in the heat pump is also presented.

  17. Evaluation of the energy efficiency of combined cycle gas turbine. Case study of Tashkent thermal power plant, Uzbekistan

    International Nuclear Information System (INIS)

    Aminov, Zarif; Nakagoshi, Nobukazu; Xuan, Tran Dang; Higashi, Osamu; Alikulov, Khusniddin

    2016-01-01

    Highlights: • The combined cycle power plant (CCPP) has a steam turbine and a gas turbine. • Fossil fuel savings and reduction of the CCGT of was evaluated. • The performance of a three pressure CCGT is modelled under different modes. • Energy efficiency of the combined cycle was 58.28%. • An annual reduction of 1760.18 tNO_x/annum and 981.25 ktCO_2/annum can be achieved. - Abstract: The power generation of Tashkent Thermal Power Plant (TPP) is based on conventional power units. Moreover, the facility suffers from limited efficiency in electricity generation. The plant was constructed during the Soviet era. Furthermore, the power plant is being used for inter-hour power generation regulation. As a result, the efficiency can be reduced by increasing specific fuel consumption. This research focuses on the evaluation of the energy efficiency of the combined cycle gas turbine (CCGT) for the Tashkent TPP. Specifically, the objective is an evaluation of fossil fuel savings and reduction of CO_2 and NO_x emissions with the using CCGT technology at conventional power plant. The proposed combined cycle power plant (CCPP) includes an existing steam turbine (ST) with 160 MW capacity, heat recovery steam generator (HRSG), and gas turbine (GT) technology with 300 MW capacity. The performance of a three pressure CCGT is modelled under different modes. As a result, the efficiency of the combined cycle was evaluated at 58.28%, while the conventional cycle had an efficiency of 34.5%. We can achieve an annual reduction of 1760.18 tNO_x/annum and 981.25 ktCO_2/annum.

  18. The use of salinity contrast for density difference compensation to improve the thermal recovery efficiency in high-temperature aquifer thermal energy storage systems

    Science.gov (United States)

    van Lopik, Jan H.; Hartog, Niels; Zaadnoordijk, Willem Jan

    2016-08-01

    The efficiency of heat recovery in high-temperature (>60 °C) aquifer thermal energy storage (HT-ATES) systems is limited due to the buoyancy of the injected hot water. This study investigates the potential to improve the efficiency through compensation of the density difference by increased salinity of the injected hot water for a single injection-recovery well scheme. The proposed method was tested through numerical modeling with SEAWATv4, considering seasonal HT-ATES with four consecutive injection-storage-recovery cycles. Recovery efficiencies for the consecutive cycles were investigated for six cases with three simulated scenarios: (a) regular HT-ATES, (b) HT-ATES with density difference compensation using saline water, and (c) theoretical regular HT-ATES without free thermal convection. For the reference case, in which 80 °C water was injected into a high-permeability aquifer, regular HT-ATES had an efficiency of 0.40 after four consecutive recovery cycles. The density difference compensation method resulted in an efficiency of 0.69, approximating the theoretical case (0.76). Sensitivity analysis showed that the net efficiency increase by using the density difference compensation method instead of regular HT-ATES is greater for higher aquifer hydraulic conductivity, larger temperature difference between injection water and ambient groundwater, smaller injection volume, and larger aquifer thickness. This means that density difference compensation allows the application of HT-ATES in thicker, more permeable aquifers and with larger temperatures than would be considered for regular HT-ATES systems.

  19. Evaluation of the thermal efficiency and a cost analysis of different types of ground heat exchangers in energy piles

    International Nuclear Information System (INIS)

    Yoon, Seok; Lee, Seung-Rae; Xue, Jianfeng; Zosseder, Kai; Go, Gyu-Hyun; Park, Hyunku

    2015-01-01

    Highlights: • We performed field TPT with W and coil-type GHEs in energy piles. • We evaluated heat exchange rates from TPT results. • Field TPT results were compared with numerical analysis. • Cost analysis with GSHP design method was conducted for each type of GHEs in energy piles. - Abstract: This paper presents an experimental and numerical study of the results of a thermal performance test using precast high-strength concrete (PHC) energy piles with W and coil-type ground heat exchangers (GHEs). In-situ thermal performance tests (TPTs) were conducted for four days under an intermittent operation condition (8 h on; 16 h off) on W and coil-type PHC energy piles installed in a partially saturated weathered granite soil deposit. In addition, three-dimensional finite element analyses were conducted and the results were compared with the four-day experimental results. The heat exchange rates were also predicted for three months using the numerical analysis. The heat exchange rate of the coil-type GHE showed 10–15% higher efficiency compared to the W-type GHE in the energy pile. However, in considering the cost for the installation of the heat exchanger and cement grouting the additional cost of W-type GHE in energy pile was 200–250% cheaper than coil-type GHE under the condition providing equivalent thermal performance. Furthermore, the required lengths of the W, 3U and coil-type GHEs in the energy piles were calculated based on the design process of Kavanaugh and Rafferty. The additional cost for the W and 3U types of GHEs were also 200–250% lower than that of the coil-type GHE. However, the required number of piles was much less with the coil-type GHE as compared to the W and 3U types of GHEs. They are advantageous in terms of the construction period, and further, selecting the coil-type GHE could be a viable option when there is a limitation in the number of piles in consideration of the scale of the building.

  20. Energy Saving Alignment Strategy: Achieving energy efficiency in urban buildings by matching occupant temperature preferences with a building’s indoor thermal environment

    International Nuclear Information System (INIS)

    Xu, Xiaoqi; Culligan, Patricia J.; Taylor, John E.

    2014-01-01

    Highlights: • A novel strategy for energy savings in multi-family buildings is presented. • A household’s thermal preferences are matched with a unit’s thermal environment. • Potential energy savings are examined using public housing as a test case. • 2.1–42.0% primary energy savings are shown, depending on climate location. - Abstract: Existing strategies for residential energy savings through physical renovation or motivating occupant energy conservation behavior can be costly and/or have transitory effects. Focusing on multi-family dwellings, an important subset of the urban residential sector, we propose an Energy Saving Alignment Strategy (ESAS) that has advantageous cost-effectiveness and a long-lasting influence. By aligning the distribution of residents’ thermostat preferences with the indoor temperature, ESAS aims to maximize thermal comfort and, accordingly, energy savings in multi-family buildings where indoor temperatures vary between apartments as a function of apartment orientation and floor level. Using a case study of a 1084-apartment public housing complex in New York, we classify both occupants’ thermostat preferences and apartments’ operative temperatures into five groups, and optimize energy efficiency by assigning each group of occupants to the group of apartments that best aligns with their thermostat preference. We test ESAS in eight cities representing all four U.S. census regions and six climate zones. Simulation results reveal 2.1–42.0% in energy savings compared to random apartment assignments depending on geographic location, with the highest energy reductions occurring in cities with mild climates, where the range of occupant thermostat preferences coincides with the natural indoor temperature range. We conclude by providing suggested guidelines on how ESAS might work in practice, and recommendations for extending ESAS research

  1. Parameter effect of a phase change thermal energy storage unit with one shell and one finned tube on its energy efficiency ratio and heat storage rate

    International Nuclear Information System (INIS)

    Wang, Wei-Wei; Wang, Liang-Bi; He, Ya-Ling

    2016-01-01

    Highlights: • The parameter effect on the performance of PCTES unit using fins is reported. • The configurations of PCTES unit using fins in optimum performance are suggested. • Two parameters to indicate the effects of PCM and tube material properties are found. • The working conditions of PCTES unit using fins in optimum performance are analyzed. - Abstract: The performance of a phase change thermal energy storage (PCTES) unit using circular finned tube is affected by many parameters. Thorough studies of the parameter effect on the performance of PCTES unit are strongly required in its optimum design process. Based on a reported energy efficiency ratio and a newly defined parameter named the heat storage rate, the parameter effect on the performance of PCTES unit using circular finned tube is numerically investigated. When the fin pitch is greater than 4 times of the inner radius of the tube, the fin height and the fin thickness have little effect on the energy efficiency ratio and the heat storage rate. When the fin pitch is small, the performance of PCTES unit becomes better using large fin height and width. The energy efficiency ratio and the heat storage rate are more sensitive to the outer tube diameter. The performance of PCTES unit using circular finned tube is best when water is used as the heat transfer fluid (HTF). When the fluid flow of HTF is in a laminar state, the energy efficiency ratio and the heat storage rate are larger than that in a turbulent state.

  2. A thermally regenerative ammonia-based battery for efficient harvesting of low-grade thermal energy as electrical power

    KAUST Repository

    Zhang, Fang; Liu, Jia; Yang, Wulin; Logan, Bruce E.

    2015-01-01

    addition to the anolyte (2 M ammonia in a copper-nitrate electrolyte) of a single TRAB cell produced a maximum power density of 115 ± 1 W m-2 (based on projected area of a single copper mesh electrode), with an energy density of 453 W h m-3 (normalized

  3. Complex thermal energy conversion systems for efficient use of locally available biomass

    International Nuclear Information System (INIS)

    Kalina, Jacek

    2016-01-01

    This paper is focused on a theoretical study in search for new technological solutions in the field of electricity generation from biomass in small-scale distributed cogeneration systems. The purpose of this work is to draw readers' attention to possibilities of design complex multi-component hybrid and combined technological structures of energy conversion plants for effective use of locally available biomass resources. As an example, there is presented analysis of cogeneration system that consists of micro-turbine, high temperature fuel cell, inverted Bryton cycle module and biomass gasification island. The project assumes supporting use of natural gas and cooperation of the plant with a low-temperature district heating network. Thermodynamic parameters, energy conversion effectiveness and economic performance are examined. Results show relatively high energy conversion performance and on the other hand weak financial indices of investment projects at the current level of energy prices. It is however possible under certain conditions to define an optimistic business model that leads to a feasible project. - Highlights: • Concept of biomass energy conversion plant is proposed and theoretically analysed. • MCFC type fuel cell is fuelled with biomass gasification gas. • Natural gas fired microturbine is considered as a source of continuous power. • Inverted Bryton Cycle is considered for utilisation of high temperature exhaust gas.

  4. Sensitivity analysis of recovery efficiency in high-temperature aquifer thermal energy storage with single well

    DEFF Research Database (Denmark)

    Jeon, Jun-Seo; Lee, Seung-Rae; Pasquinelli, Lisa

    2015-01-01

    ., it is getting more attention as these issues are gradually alleviated. In this study, a sensitivity analysis of recovery efficiency in two cases of HT-ATES system with a single well is conducted to select key parameters. For a fractional factorial design used to choose input parameters with uniformity...... with Smoothly Clopped Absolute Deviation Penalty, is utilized. Finally, the sensitivity analysis is performed based on the variation decomposition. According to the result of sensitivity analysis, the most important input variables are selected and confirmed to consider the interaction effects for each case...

  5. Methodology for calculation of carbon emission and energy generation efficiency by fossil coal thermal power plants

    International Nuclear Information System (INIS)

    Licks, Leticia A.; Pires, Marcal

    2008-01-01

    This work intends to evaluate the emissions of carbon dioxide (CO 2 ) emitted by the burning of fossil coal in Brazil. So, a detailed methodology is proposed for calculation of CO 2 emissions from the carbon emission coefficients specific for the Brazilian carbons. Also, the using of secondary fuels (fuel oil and diesel oil) were considered and the power generation for the calculation of emissions and efficiencies of each power plant as well. The obtained results indicate carbon emissions for the year 2002 approximately of the order of 1,794 Gg, with 20% less than the obtained by the official methodology (MCT). Such differences are related to the non consideration of the humidity containment of the coals as well as the using of generic coefficients not adapted to the Brazilian coals. The obtained results indicate the necessity to review the emission inventories and the modernization of the burning systems aiming the increase the efficiency and reduction of the CO 2 and other pollutants, as an alternative for maintaining the sustainable form of using the fossil coal in the country

  6. Thermal and Performance Analysis of a Gasification Boiler and Its Energy Efficiency Optimization

    Directory of Open Access Journals (Sweden)

    Jan Valíček

    2017-07-01

    Full Text Available The purpose of this study was to determine a method for multi-parametric output regulation of a gasification boiler especially designed for heating or for hot water heating in buildings. A new method of regulation is offered, namely more parametric regulation via proportional-integral-derivative (PID controllers that are capable of controlling the calculated values of pressure, temperature and fan speed. These values of pressure, temperature and fan speed are calculated in a completely new way, and calculations of setpoints for determination of optimal parameters lead to an increase in boilers efficiency and power output. Results of measurements show that changes at the mouth of the stack draft due atmospheric influences occur in times with high intensity and high frequency, while power parameters, or boiler power output amplitudes and fan speed automatically “copy” those changes proportionally due to instantaneous fan speed changes. The proposed method of regulation of the gasification boiler power output according to the technical solution enables a simple, cheap, express and continuous maintenance of high power output at low concentrations of the exhaust gases of the gasification boilers from the viewpoint of the boiler user, as well as from the perspective of development and production it allows a continuous control monitoring of these parameters.

  7. Using a new programme (THERCOM) to predict thermal comfort as a base to design energy efficient buildings

    OpenAIRE

    Al-Khatri, Hanan; Gadi, Mohamed

    2014-01-01

    A strong relationship relates the thermal comfort and the consumption of energy, especially in the hot arid climate where the installation of HVAC systems is unavoidable. In fact, it has been reported that the HVAC systems are responsible for consuming huge amounts of the total energy used by the buildings that can globally reach up to 40% of the total primary energy requirement. The future estimations indicate that the energy consumption is likely to continue growing in the developed economi...

  8. Seasonal Thermal-Energy Storage: A Critical Review on BTES Systems, Modeling, and System Design for Higher System Efficiency

    Directory of Open Access Journals (Sweden)

    Michael Lanahan

    2017-05-01

    Full Text Available Buildings consume approximately ¾ of the total electricity generated in the United States, contributing significantly to fossil fuel emissions. Sustainable and renewable energy production can reduce fossil fuel use, but necessitates storage for energy reliability in order to compensate for the intermittency of renewable energy generation. Energy storage is critical for success in developing a sustainable energy grid because it facilitates higher renewable energy penetration by mitigating the gap between energy generation and demand. This review analyzes recent case studies—numerical and field experiments—seen by borehole thermal energy storage (BTES in space heating and domestic hot water capacities, coupled with solar thermal energy. System design, model development, and working principle(s are the primary focus of this analysis. A synopsis of the current efforts to effectively model BTES is presented as well. The literature review reveals that: (1 energy storage is most effective when diurnal and seasonal storage are used in conjunction; (2 no established link exists between BTES computational fluid dynamics (CFD models integrated with whole building energy analysis tools, rather than parameter-fit component models; (3 BTES has less geographical limitations than Aquifer Thermal Energy Storage (ATES and lower installation cost scale than hot water tanks and (4 BTES is more often used for heating than for cooling applications.

  9. Energy efficiency; Efficacite energetique

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-06-15

    This road-map proposes by the Group Total aims to inform the public on the energy efficiency. It presents the energy efficiency and intensity around the world with a particular focus on Europe, the energy efficiency in industry and Total commitment. (A.L.B.)

  10. Energy efficiency through energy audit

    International Nuclear Information System (INIS)

    Esan, A. A.

    2000-08-01

    Energy is an essential factor to economic and social development and improved standards of living in developing countries. Nigeria in particular. There is a strong need for greater energy efficiency in every sector of economy in order to reduce costs. enhance competitiveness, conserve energy resources and reduce environmental impacts associated with production, distribution and use of energy. Energy auditing and monitoring has a significant role in any energy management and conservation project. Energy auditing as an important part of industrial energy management on plant level, represents a complex of activities aiming at the efficient use of energy. The activities are undertaken by a team of experts who use a set of measuring instruments to monitor and evaluate all the necessary data to elaborate a package of recommendations on improvements in the field of energy efficiency and possible product quality. The inefficient conversion and use of energy have been identified as a central problem for all developing countries, Nigeria inclusive, since they all consume significantly higher amounts of energy per unit of GDP than OECD countries. This aggravates energy-related environmental problems and is also a burden on domestic resources and foreign exchange. Energy prices have risen drastically in many developing countries, while energy intensities remain high. Price changes alone are not rapidly translating energy efficiency improvements. Identifying and removing the obstacles to greater energy efficiency should be priority for government in developing countries. This is why the Energy Commission, an apex organ of government on Energy matters in all its ramifications is out to encourage relatively low-cost energy audits for the Textile industries - such audits can identify ''good house-keeping's' measures, such as simply process improvements, that reduce energy consumption and operating costs. This will be followed by the training of plant workers/energy managers

  11. Using Leaf Chlorophyll to Parameterize Light-Use-Efficiency Within a Thermal-Based Carbon, Water and Energy Exchange Model

    Science.gov (United States)

    Houlborg, Rasmus; Anderson, Martha C.; Daughtry, C. S. T.; Kustas, W. P.; Rodell, Matthew

    2010-01-01

    Chlorophylls absorb photosynthetically active radiation and thus function as vital pigments for photosynthesis, which makes leaf chlorophyll content (C(sub ab) useful for monitoring vegetation productivity and an important indicator of the overall plant physiological condition. This study investigates the utility of integrating remotely sensed estimates of C(sub ab) into a thermal-based Two-Source Energy Balance (TSEB) model that estimates land-surface CO2 and energy fluxes using an analytical, light-use-efficiency (LUE) based model of canopy resistance. The LUE model component computes canopy-scale carbon assimilation and transpiration fluxes and incorporates LUE modifications from a nominal (species-dependent) value (LUE(sub n)) in response to short term variations in environmental conditions, However LUE(sub n) may need adjustment on a daily timescale to accommodate changes in plant phenology, physiological condition and nutrient status. Day to day variations in LUE(sub n) were assessed for a heterogeneous corn crop field in Maryland, U,S.A. through model calibration with eddy covariance CO2 flux tower observations. The optimized daily LUE(sub n) values were then compared to estimates of C(sub ab) integrated from gridded maps of chlorophyll content weighted over the tower flux source area. The time continuous maps of daily C(sub ab) over the study field were generated by focusing in-situ measurements with retrievals generated with an integrated radiative transfer modeling tool (accurate to within +/-10%) using at-sensor radiances in green, red and near-infrared wavelengths acquired with an aircraft imaging system. The resultant daily changes in C(sub ab) within the tower flux source area generally correlated well with corresponding changes in daily calibrated LUE(sub n) derived from the tower flux data, and hourly water, energy and carbon flux estimation accuracies from TSEB were significantly improved when using C(sub ab) for delineating spatio

  12. Polish Foundation for Energy Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    The Polish Foundation for Energy Efficiency (FEWE) was established in Poland at the end of 1990. FEWE, as an independent and non-profit organization, has the following objectives: to strive towards an energy efficient national economy, and to show the way and methods by use of which energy efficiency can be increased. The activity of the Foundation covers the entire territory of Poland through three regional centers: in Warsaw, Katowice and Cracow. FEWE employs well-known and experienced specialists within thermal and power engineering, civil engineering, economy and applied sciences. The organizer of the Foundation has been Battelle Memorial Institute - Pacific Northwest Laboratories from the USA.

  13. The Energy Efficient Enterprise

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Bashir

    2010-09-15

    Since rising energy costs have become a crucial factor for the economy of production processes, the optimization of energy efficiency is of essential importance for industrial enterprises. Enterprises establish energy saving programs, specific to their needs. The most important elements of these energy efficiency programs are energy savings, energy controlling, energy optimization, and energy management. This article highlights the industrial enterprise approach to establish sustainable energy management programs based on the above elements. Globally, if organizations follow this approach, they can significantly reduce the overall energy consumption and cost.

  14. Reconsidering energy efficiency

    International Nuclear Information System (INIS)

    Goldoni, Giovanni

    2007-01-01

    Energy and environmental policies are reconsidering energy efficiency. In a perfect market, rational and well informed consumers reach economic efficiency which, at the given prices of energy and capital, corresponds to physical efficiency. In the real world, market failures and cognitive frictions distort the consumers from perfectly rational and informed choices. Green incentive schemes aim at balancing market failures and directing consumers toward more efficient goods and services. The problem is to fine tune the incentive schemes [it

  15. Recent developments in thermally-driven seawater desalination: Energy efficiency improvement by hybridization of the MED and AD cycles

    KAUST Repository

    Ng, Kim Choon; Thu, Kyaw; Oh, Seungjin; Ang, Li; Shahzad, Muhammad Wakil; Ismail, Azhar Bin

    2015-01-01

    -driven to adsorption desalination (AD) cycles where significant thermodynamic synergy can be attained when cycles are combined. For these hybrid cycles, a quantum improvement in energy efficiency as well as in increase in water production can be expected. The advent

  16. Thermal solar energy

    International Nuclear Information System (INIS)

    Gonzalez, J.C.; Leal C, H.

    1998-01-01

    Some relative aspects to the development and current state of thermal solar energy are summarized, so much at domestic level as international. To facilitate the criteria understanding as the size of the facilities in thermal solar systems, topics as availability of the solar resource and its interactions with the matter are included. Finally, some perspectives for the development of this energetic alternative are presented

  17. Can storage reduce electricity consumption? A general equation for the grid-wide efficiency impact of using cooling thermal energy storage for load shifting

    Science.gov (United States)

    Deetjen, Thomas A.; Reimers, Andrew S.; Webber, Michael E.

    2018-02-01

    This study estimates changes in grid-wide, energy consumption caused by load shifting via cooling thermal energy storage (CTES) in the building sector. It develops a general equation for relating generator fleet fuel consumption to building cooling demand as a function of ambient temperature, relative humidity, transmission and distribution current, and baseline power plant efficiency. The results present a graphical sensitivity analysis that can be used to estimate how shifting load from cooling demand to cooling storage could affect overall, grid-wide, energy consumption. In particular, because power plants, air conditioners and transmission systems all have higher efficiencies at cooler ambient temperatures, it is possible to identify operating conditions such that CTES increases system efficiency rather than decreasing it as is typical for conventional storage approaches. A case study of the Dallas-Fort Worth metro area in Texas, USA shows that using CTES to shift daytime cooling load to nighttime cooling storage can reduce annual, system-wide, primary fuel consumption by 17.6 MWh for each MWh of installed CTES capacity. The study concludes that, under the right circumstances, cooling thermal energy storage can reduce grid-wide energy consumption, challenging the perception of energy storage as a net energy consumer.

  18. Clock Gating Based Energy Efficient and Thermal Aware Design for Vedic Equation Solver on 28nm and 40nm FPGA

    DEFF Research Database (Denmark)

    Pandey, Bishwajeet; Pandey, Sujeet; Sharma, Shivani

    2016-01-01

    In this paper, we are integrating clock gating in design of energy efficient equation solver circuits based on Vedic mathematics. Clock gating is one of the best energy efficient techniques. The Sutra 'SunyamSamyasamuccaye' says thatif sum of numerator and sum of denominator is same then we can e......, 94.54% for 1800MHz, and 94.02% for 2.2GHz, when we use gated clock instead of un gated one on 40nm FPGA and temperature is 329.85K. Power consumption in 28nm FPGA is less than 40nm FPGA....

  19. Energy Efficiency Collaboratives

    Energy Technology Data Exchange (ETDEWEB)

    Li, Michael [US Department of Energy, Washington, DC (United States); Bryson, Joe [US Environmental Protection Agency, Washington, DC (United States)

    2015-09-01

    Collaboratives for energy efficiency have a long and successful history and are currently used, in some form, in more than half of the states. Historically, many state utility commissions have used some form of collaborative group process to resolve complex issues that emerge during a rate proceeding. Rather than debate the issues through the formality of a commission proceeding, disagreeing parties are sent to discuss issues in a less-formal setting and bring back resolutions to the commission. Energy efficiency collaboratives take this concept and apply it specifically to energy efficiency programs—often in anticipation of future issues as opposed to reacting to a present disagreement. Energy efficiency collaboratives can operate long term and can address the full suite of issues associated with designing, implementing, and improving energy efficiency programs. Collaboratives can be useful to gather stakeholder input on changing program budgets and program changes in response to performance or market shifts, as well as to provide continuity while regulators come and go, identify additional energy efficiency opportunities and innovations, assess the role of energy efficiency in new regulatory contexts, and draw on lessons learned and best practices from a diverse group. Details about specific collaboratives in the United States are in the appendix to this guide. Collectively, they demonstrate the value of collaborative stakeholder processes in producing successful energy efficiency programs.

  20. Energy efficiency and behaviour

    DEFF Research Database (Denmark)

    Carstensen, Trine Agervig; Kunnasvirta, Annika; Kiviluoto, Katariina

    separate key aspects hinders strategic energy efficiency planning. For this reason, the PLEEC project – “Planning for Energy Efficient Cities” – funded by the EU Seventh Framework Programme uses an integrative approach to achieve the sus‐ tainable, energy– efficient, smart city. By coordinating strategies...... to conduct behavioural interventions, to be presented in Deliverable 5.5., the final report. This report will also provide valuable information for the WP6 general model for an Energy-Smart City. Altogether 38 behavioural interventions are analysed in this report. Each collected and analysed case study...... of the European Union’s 20‐20‐20 plan is to improve energy efficiency by 20% in 2020. However, holistic knowledge about energy efficiency potentials in cities is far from complete. Currently, a WP4 location in PLEEC project page 3 variety of individual strategies and approaches by different stakeholders tackling...

  1. Different I/O Standard and Technology Based Thermal Aware Energy Efficient Vedic Multiplier Design for Green Wireless Communication on FPGA

    DEFF Research Database (Denmark)

    Goswami, Kavita; Pandey, Bishwajeet; Kumar, Tanesh

    2017-01-01

    and that eventually decrease power dissipation of wireless communications systems. In order to study the effect of different process technology (40, 65, 90 nm) on our design, a novel design is implemented on 40, 65 and 90 nm based FPGA. In this work, we are integrating thermal aware design approach for energy......This paper deals with low power multiplier design that plays a significant role in green wireless communications systems. Over the period of time, researchers have proposed various multiplier designs in order to get high speed. Vedic multiplier is considered as one of the low power multiplier along...... with high speed as compared with traditional array and booth multipliers. Vedic Multiplier contains a total of sixteen algorithms/sutras for predominantly logical operations. This research focuses on thermal aspects and energy efficiency of wireless communications systems with the thermal aware low power...

  2. Energy efficient design

    International Nuclear Information System (INIS)

    1991-01-01

    Solar Applications and Energy Efficiency in Building Design and Town Planning (RER/87/006) is a United Nations Development Programme (UNDP) project of the Governments of Albania, Bulgaria, Cyprus, The Czech and Slovak Federal Republic, France, Hungary, Malta, Poland, Turkey, United Kingdom and Yugoslavia. The project began in 1988 and comes to a conclusion at the end of 1991. It is to enhance the professional skills of practicing architects, engineers and town planners in European countries to design energy efficient buildings which reduce energy consumption and make greater use of passive solar heating and natural cooling techniques. The United Nations Economic Commission for Europe (ECE) is the Executing Agency of the project which is implemented under the auspices of the Committee on Energy, General Energy Programme of Work for 1990-1994, sub-programme 5 Energy Conservation and Efficiency (ECE/ENERGY/15). The project has five main outputs or results: an international network of institutions for low energy building design; a state-of-the-art survey of energy use in the built environment of European IPF countries; a simple computer program for energy efficient building design; a design guide and computer program operators' manual; and a series of international training courses in participating European IPF countries. Energy Efficient Design is the fourth output of the project. It comprises the design guide for practicing architects and engineers, for use mainly in mid-career training courses, and the operators' manual for the project's computer program

  3. I/O Standard Based Thermal/Energy Efficient Green Communication For Wi-Fi Protected Access on FPGA

    DEFF Research Database (Denmark)

    Kumar, Tanesh; Pandey, Bishwajeet; Das, Teerath

    2014-01-01

    In this paper, we analyzed how does life and reliability of an integrated circuit is affected when it is operated in different regions under different temperatures. We have taken Fibonacci generator as our target circuit and LVCMOS as I/O standards. WPA and WPA2 (Wi-Fi Protected Access) key can...... be generated with Fibonacci generator. Here, thermal efficient green Fibonacci Generator is used to generate key for Wi-Fi Protected Access in order to make green communication possible under different room temperature. By analysis it is observed that at standard normal temperature (21degrees C), LVCMOS12 have...

  4. Financing Energy Efficient Homes

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    Existing buildings require over 40% of the world's total final energy consumption, and account for 24% of world CO2 emissions (IEA, 2006). Much of this consumption could be avoided through improved efficiency of building energy systems (IEA, 2006) using current, commercially-viable technology. In most cases, these technologies make economic sense on a life-cycle cost analysis (IEA, 2006b). Moreover, to the extent that they reduce dependence on risk-prone fossil energy sources, energy efficient technologies also address concerns of energy security.

  5. Financing Energy Efficient Homes

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    Existing buildings require over 40% of the world's total final energy consumption, and account for 24% of world CO2 emissions (IEA, 2006). Much of this consumption could be avoided through improved efficiency of building energy systems (IEA, 2006) using current, commercially-viable technology. In most cases, these technologies make economic sense on a life-cycle cost analysis (IEA, 2006b). Moreover, to the extent that they reduce dependence on risk-prone fossil energy sources, energy efficient technologies also address concerns of energy security.

  6. National energy efficiency programme

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    This paper focusses on energy conservation and specifically on energy efficiency which includes efficiency in the production, delivery and utilisation of energy as part of the total energy system of the economy. A National Energy Efficiency Programme is being launched in the Eighth Plan that will take into account both macro level and policy and planning considerations as well as micro level responses for different category of users in the industry, agriculture, transport and domestic sectors. The need for such a National Energy Efficiency Programme after making an assessment of existing energy conservation activities in the country is discussed. The broad framework and contents of the National Energy Efficiency Programme have been outlined and the Eighth Plan targets for energy conservation and their break-up have been given. These targets, as per the Eighth Plan document are 5000 MW in electricity installed capacity and 6 million tonnes of petroleum products by the terminal year of the Eighth Plan. The issues that need to be examined for each sector for achieving the above targets for energy conservation in the Eighth Plan are discussed briefly. They are: (a) policy and planning, (b) implementation arrangements which include the institutional setup and selective legislation, (c) technological requirements, and (d) resource requirements which include human resources and financial resources. (author)

  7. Energy Efficiency Center - Overview

    International Nuclear Information System (INIS)

    Obryk, E.

    2000-01-01

    Full text: The Energy Efficiency Center (EEC) activities have been concentrated on Energy Efficiency Network (SEGE), education and training of energy auditors. EEC has started studies related to renewable fuels (bio fuel, wastes) and other topics related to environment protection. EEC has continued close collaboration with Institute for Energy Technology, Kjeller, Norway. It has been organized and conducted Seminar and Workshop on ''How to Reduce Energy and Water Cost in Higher Education Buildings'' for general and technical managers of the higher education institutions. This Seminar was proceeded by the working meeting on energy efficiency strategy in higher education at the Ministry of National Education. EEC has worked out proposal for activities of Cracow Regional Agency for Energy Efficiency and Environment and has made offer to provide services for this Agency in the field of training, education and consulting. The vast knowledge and experiences in the field of energy audits have been used by the members of EEC in lecturing at energy auditors courses authorized by the National Energy Efficiency Agency (KAPE). Altogether 20 lectures have been delivered. (author)

  8. Transport Energy Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    Transport is the sector with the highest final energy consumption and, without any significant policy changes, is forecast to remain so. In 2008, the IEA published 25 energy efficiency recommendations, among which four are for the transport sector. The recommendations focus on road transport and include policies on improving tyre energy efficiency, fuel economy standards for both light-duty vehicles and heavy-duty vehicles, and eco-driving. Implementation of the recommendations has been weaker in the transport sector than others. This paper updates the progress that has been made in implementing the transport energy efficiency recommendations in IEA countries since March 2009. Many countries have in the last year moved from 'planning to implement' to 'implementation underway', but none have fully implemented all transport energy efficiency recommendations. The IEA calls therefore for full and immediate implementation of the recommendations.

  9. Advanced energy efficient windows

    DEFF Research Database (Denmark)

    Thomsen, Kirsten Engelund

    2007-01-01

    Windows should be paid special attention as they contribute a significant part of the total heat-loss coefficient of the building. Contrary to other parts of the thermal envelope the windows are not only heat loosers, but may gain heat in the day-time. Therefore there are possibilities for large...... energy savings. In terms of energy, windows occupy a special position compared with other thermal envelope structures due to their many functions: 1) windows let daylight into the building and provide occupants with visual contact with their surroundings 2) windows protect against the outdoor climate 3......) windows transmit solar energy that may contribute to a reduction of energy consumption, but which may also lead to unpleasant overheating. In the following paragraphs the current use of windows is reviewed with an emphasis on energy, while special products like solar protection glazing and security...

  10. Solar thermal energy receiver

    Science.gov (United States)

    Baker, Karl W. (Inventor); Dustin, Miles O. (Inventor)

    1992-01-01

    A plurality of heat pipes in a shell receive concentrated solar energy and transfer the energy to a heat activated system. To provide for even distribution of the energy despite uneven impingement of solar energy on the heat pipes, absence of solar energy at times, or failure of one or more of the heat pipes, energy storage means are disposed on the heat pipes which extend through a heat pipe thermal coupling means into the heat activated device. To enhance energy transfer to the heat activated device, the heat pipe coupling cavity means may be provided with extensions into the device. For use with a Stirling engine having passages for working gas, heat transfer members may be positioned to contact the gas and the heat pipes. The shell may be divided into sections by transverse walls. To prevent cavity working fluid from collecting in the extensions, a porous body is positioned in the cavity.

  11. Energy efficiency in Finland

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    In Finland a significant portion of energy originates from renewable sources and cogeneration, that is, combined production of electricity and heat. Combined heat and electricity production is typical in the Finnish industry and in the district heating sector. One third of all electricity and 15 % of district heating is produced by cogeneration. District heating schemes provide about 45 % of heat in buildings. Overall efficiency in industry exceeds 80 % and is even higher in the district heating sector. In 1996 25 % of Finland`s primary energy was produced from renewable energy sources which is a far higher proportion than the European Union average of 6 %. Finland is one of the leading users of bioenergy. Biomass including peat, provides approximately 50 % of fuel consumed by industry and is utilised in significant amounts in combined heat and electricity plants. For example, in the pulp and paper industry, by burning black liquor and bark during the production of chemical pulp, significant amounts of energy are generated and used in paper mills. Conservation and efficient use of energy are central to the Finnish Government`s Energy Strategy. The energy conservation programme aims to increase energy efficiency by 10-20 % by the year 2010. Energy saving technology plays a key role in making the production and use of energy more efficient. In 1996 of FIM 335 million (ECU 57 million) spent on funding research, FIM 120 million (ECU 20 million) was spent on research into energy conservation

  12. Efficient use of energy

    CERN Document Server

    Dryden, IGC

    2013-01-01

    The Efficient Use of Energy, Second Edition is a compendium of papers discussing the efficiency with which energy is used in industry. The collection covers relevant topics in energy handling and describes the more important features of plant and equipment. The book is organized into six parts. Part I presents the various methods of heat production. The second part discusses the use of heat in industry and includes topics in furnace design, industrial heating, boiler plants, and water treatment. Part III deals with the production of mechanical and electrical energy. It tackles the principles o

  13. Energy Efficient Cryogenics

    Science.gov (United States)

    Meneghelli, Barry J.; Notardonato, William; Fesmire, James E.

    2016-01-01

    The Cryogenics Test Laboratory, NASA Kennedy Space Center, works to provide practical solutions to low-temperature problems while focusing on long-term technology targets for the energy-efficient use of cryogenics on Earth and in space.

  14. Input/output Buffer based Vedic Multiplier Design for Thermal Aware Energy Efficient Digital Signal Processing on 28nm FPGA

    DEFF Research Database (Denmark)

    Goswami, Kavita; Pandey, Bishwajeet; Hussain, Dil muhammed Akbar

    2016-01-01

    Multiplier is used for multiplication of a signal and a constant in digital signal processing (DSP). 28nm technology based Vedic multiplier is implemented with use of VHDL HDL, Xilinx ISE, Kintex-7 FPGA and XPower Analyzer. Vedic multiplier gain speed improvements by parallelizing the generation...... Programmable Gate Array (FPGA) in order to reduce the development cost. The development cost for Application Specific Integrated Circuits (ASICs) are high in compare to FPGA. Selection of the most energy efficient IO standards in place of signal gating is the main design methodology for design of energy...... efficient Vedic multiplier.There is 68.51%, 69.86%, 74.65%, and 78.39% contraction in total power of Vedic multiplier on 28nm Kintex-7 FPGA, when we use HSTL_II in place of HSTL_II_DCI_18 at 56.7oC, 53.5oC, 40oC and 21oC respectively....

  15. Polymeric-SiO2-PCMs for improving the thermal properties of gypsum applied in energy efficient buildings

    International Nuclear Information System (INIS)

    Borreguero, Ana M.; Serrano, Angel; Garrido, Ignacio; Rodríguez, Juan F.; Carmona, Manuel

    2014-01-01

    Highlights: • Inorganic–organic PCM microcapsules were incorporated into gypsum. • The physical and thermal properties of the gypsum composites were studied. • The gypsum composites presented better properties than some previously investigated. • 10.20 kW h/operating cycle could be saved in a room with 1 m 3 of this material. • 1.26 kg of CO 2 emissions could be reduced per one operating cycle. - Abstract: A new thermoregulating material containing the commercial paraffin Rubitherm®RT27 stabilized by SiO 2 with a polymeric shell from polystyrene–divinylbenzene (Polymeric-SiO 2 -PCMs) was incorporated into gypsum up to a 15 mass ratio respect to the initial hemihydrate in order to develop building materials with a high thermal energy store (TES) capacity. The effect of this material on the gypsum crystals and the main physical, thermal and mechanical properties were studied and compared to those caused by another three kinds of thermoregulating materials. Polymeric-SiO 2 -PCMs presented the lowest agglomeration and therefore, the best distribution into the gypsum pores. As expected, the thermoregulating effect of the PCM improved the thermal properties of the gypsum since, the higher the microcapsules content, the higher the equivalent heat capacity (c p ) and the accumulated heat power (q acc ). Considering a conversion of 100% of the accumulated heat into electricity savings, the addition of a 15% of microcapsules respect to the hemihydrate allowed to save 10.20 kW h/m 3 and, consequently, reduced the CO 2 emissions in a 1.26 kg of CO 2 per operating cycle. Besides, the addition of the Polymeric-SiO 2 -PCMs reduces the gypsum density, but it is always higher than 600 kg/m 3 , as required by the European regulation EN 13279-2. The thermal conductivity (k) is also reduced by the microcapsules addition but for the case of a content of 15%. On the other hand, the porosity is barely affected just varying always less than a 3.5%. Finally, despite of the

  16. Thermal and Daylighting Performance of Energy-Efficient Windows in Highly Glazed Residential Buildings: Case Study in Korea

    Directory of Open Access Journals (Sweden)

    Chang Heon Cheong

    2014-10-01

    Full Text Available Cooling load in highly glazed residential building can be excessively large due to uncontrolled solar energy entering the indoor space. This study focuses on the cooling load reduction and changes in the daylighting properties via the application of a double window system (DWS with shading with various surface reflectivities in highly glazed residential buildings. Evaluation of thermal and daylighting performances is carried out using simulation tools. The reductions in cooling load and energy cost through the use of DWS are evaluated through a comparative simulation considering conventional windows: a single window and a double window. Three variables of window types, natural ventilation, and shading reflectivity are reflected in the study. According to our results, implementation of DWS reduced cooling load by 43%–61%. Electricity cost during the cooling period was reduced by a maximum of 24%. However, a shading device setting that prioritizes effective cooling load reduction can greatly decrease the daylighting factor and luminance level of indoor space. A DWS implementing shading device with highly reflective at all surfaces is appropriate option for the more comfortable thermal and visual environment, while a shading device with low reflectivity at rear of the surface can contribute an additional 4% cooling load reduction.

  17. Designing for an imagined user: Provision for thermal comfort in energy-efficient extra-care housing

    International Nuclear Information System (INIS)

    Lewis, Alan

    2015-01-01

    Regarded as one solution to the problem of how to enable older people to retain their independence, extra-care housing, where each resident has their own self-contained dwelling and access to communal facilities and to care, has received extensive funding in recent years. Implicit in the concept of specialist housing is the notion of ‘special’ occupants, imagined older people. Adopting a socio-technical approach, this paper considers how ideas about ageing inform those aspects of extra-care-housing-design that relate to thermal comfort. The paper draws on semi-structured interviews with 13 people involved in the design, development and management of UK-based extra-care housing. Participants characterised imagined occupants as vulnerable to cold, at risk from fuel poverty and liable to be burned by hot surfaces or fall from high windows. These user representations were reportedly inscribed into the design of extra-care housing schemes through the inclusion of building features such as communal heating, under-floor heating, restricted window opening and heated corridors. The utilisation of stereotypical user representations of older people raises questions, given that older people's thermal comfort needs can be highly diverse. The paper explores the implications for energy demand. -- Highlights: •Explores the factors that condition energy demand in older people's housing. •Considers how user representations are scripted into building design. •Older occupants characterised as vulnerable to cold and having low incomes. •These user representations affect selection of thermal technologies. •Priority given to keeping occupants warm, leading to possible risk of overheating

  18. Implications of the energy efficiency in the attenuation of environmental impacts and the conservation of the energy: The case of the Thermal Power stations to Gas in Colombia

    International Nuclear Information System (INIS)

    Amell A, A.; Cadavid, F.J.

    1999-01-01

    In the present work a comparative analysis is done about the implication for our country, from a point of view of energetic sources conservation and environmental impact, of the execution of natural gas thermal projects with high and low efficiency technology

  19. Comparative thermal performance of static sunshade and brick cavity wall for energy efficient building envelope in composite climate

    Directory of Open Access Journals (Sweden)

    Charde Meghana

    2014-01-01

    Full Text Available Energy efficient building technologies can reduce energy consumption in buildings. In present paper effect of designed static sunshade, brick cavity wall with brick projections and their combined effect on indoor air temperature has been analyzed by constructing three test rooms each of habitable dimensions (3.0 m × 4.0 m × 3.0 m and studying hourly temperatures on typical days for one month in summer and winter each. The three rooms have also been simulated using a software and the results have been compared with the experimental results. Designed static sunshade increased indoor air temperature in winter while proposed brick cavity wall with brick projections lowered it in summer. Combined effect of building elements lowered indoor air temperature in summer and increased it in winter as compared to outdoor air temperature. It is thus useful for energy conservation in buildings in composite climate.

  20. Energy efficiency; Energieffektivisering

    Energy Technology Data Exchange (ETDEWEB)

    2009-06-15

    The Low Energy Panel will halve the consumption in buildings. The Panel has proposed a halving of consumption in the construction within 2040 and 20 percent reduction in the consumption in the industry within 2020. The Panel consider it as possible to gradually reduce consumption in buildings from the current level of 80 TWh with 10 TWh in 2020, 25 TWh in 2030 and 40 TWh in 2040. According the committee one such halving can be reached by significant efforts relating to energy efficiency, by greater rehabilitations, energy efficiency in consisting building stock and stricter requirements for new construction. For the industry field the Panel recommend a political goal to be set at least 20 percent reduction in specific energy consumption in the industry and primary industry beyond general technological development by the end of 2020. This is equivalent to approximately 17 TWh based on current level of activity. The Panel believes that a 5 percent reduction should be achieved by the end of 2012 by carrying out simple measures. The Low Energy Panel has since March 2009 considered possibilities to strengthen the authorities' work with energy efficiency in Norway. The wide complex panel adds up proposals for a comprehensive approach for increased energy efficiency in particular in the building- and industry field. The Panel has looked into the potential for energy efficiency, barriers for energy efficiency, assessment of strengths and weaknesses in the existing policy instruments and members of the Panel's recommendations. In addition the report contains a review of theoretical principles for effects of instruments together with an extensive background. One of the committee members have chosen to take special notes on the main recommendations in the report. (AG)

  1. Energy efficiency system development

    Science.gov (United States)

    Leman, A. M.; Rahman, K. A.; Chong, Haw Jie; Salleh, Mohd Najib Mohd; Yusof, M. Z. M.

    2017-09-01

    By subjecting to the massive usage of electrical energy in Malaysia, energy efficiency is now one of the key areas of focus in climate change mitigation. This paper focuses on the development of an energy efficiency system of household electrical appliances for residential areas. Distribution of Questionnaires and pay a visit to few selected residential areas are conducted during the fulfilment of the project as well as some advice on how to save energy are shared with the participants. Based on the collected data, the system developed by the UTHM Energy Team is then evaluated from the aspect of the consumers' behaviour in using electrical appliances and the potential reduction targeted by the team. By the end of the project, 60% of the participants had successfully reduced the electrical power consumption set by the UTHM Energy Team. The reasons for whether the success and the failure is further analysed in this project.

  2. Increasing the efficiency of thermal power stations

    International Nuclear Information System (INIS)

    Schwarz, N.F.

    1984-01-01

    High energy prices and an increased investment of costs in power plants as well as the necessity to minimize all kinds of environmental pollution have severe consequences on the construction and operation of thermal power stations. One of the most promising measures to cope with the mentioned problems is to raise the thermal efficiency of power plants. With the example of an Austrian electric utility it can be shown that by application of high efficiency combined cycles primary energy can be converted into electricity in a most efficient manner. Excellent operating experience has proved the high reliability of these relatively complex systems. Raising the temperature of the gas topping process still higher will not raise the efficiency considerably. In this respect a Rankine cycle is superior to a Brayton cycle. In a temperature range of 850 to 900 0 C were conventional materials with known properties can still be used, only the alkali metals cesium and potassium have the necessary physical and thermodynamic properties for application in Rankine topping cycles. Building on experience gained in the Fast Breeder development and from the US space program, a potassium topping cycle linked to a conventional water steam cycle with an intermediate diphenyl vapour cycle has been proposed which should give thermal efficiencies in excess of 50%. In a multi-national program this so called Treble Rankine Cycle is being investigated under the auspices of the International Energy Agency. Work is in progress to investigate the technical and economic feasibility of this energy conversion system. Experimental investigations are already under way in the Austrian Research Center Seibersdorf where high temperature liquid metal test facilities have been operated since 1968. (Author)

  3. Manipulation of Thermally Activated Delayed Fluorescence of Blue Exciplex Emission: Fully Utilizing Exciton Energy for Highly Efficient Organic Light Emitting Diodes with Low Roll-Off.

    Science.gov (United States)

    Wang, Zixing; Wang, Hedan; Zhu, Jun; Wu, Peng; Shen, Bowen; Dou, Dehai; Wei, Bin

    2017-06-28

    The application of exciplex energy has become a unique way to achieve organic light-emitting diodes (OLEDs) with high efficiencies, low turn-on voltage, and low roll-off. Novel δ-carboline derivatives with high triplet energy (T 1 ≈ 2.92 eV) and high glass transition temperature (T g ≈ 153 °C) were employed to manipulate exciplex emissions in this paper. Deep blue (peak at 436 nm) and pure blue (peak at 468 nm) thermally activated delayed fluorescence (TADF) of exciplex OLEDs were demonstrated by utilizing them as emitters with the maximum current efficiency (CE) of 4.64 cd A -1 , power efficiency (PE) of 2.91 lm W -1 , and external quantum efficiency (EQE) of 2.36%. Highly efficient blue phosphorescent OLEDs doped with FIrpic showed a maximum CE of 55.6 cd A -1 , PE of 52.9 lm W -1 , and EQE of 24.6% respectively with very low turn on voltage at 2.7 V. The devices still remain high CE of 46.5 cd A -1 at 100 cd m -2 , 45.4 cd A -1 at 1000 cd m -2 and 42.3 cd A -1 at 5000 cd m -2 with EQE close to 20% indicating low roll-off. Manipulating blue exciplex emissions by chemical structure gives an ideal strategy to fully utilize all exciton energies for lighting of OLEDs.

  4. Energy Efficient Digital Networks

    Energy Technology Data Exchange (ETDEWEB)

    Lanzisera, Steven [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Brown, Richard [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2013-01-01

    Digital networks are the foundation of the information services, and play an expanding and indispensable role in our lives, via the Internet, email, mobile phones, etc. However, these networks consume energy, both through the direct energy use of the network interfaces and equipment that comprise the network, and in the effect they have on the operating patterns of devices connected to the network. The purpose of this research was to investigate a variety of technology and policy issues related to the energy use caused by digital networks, and to further develop several energy-efficiency technologies targeted at networks.

  5. Productivity and energy efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Lovins, H. [Rocky Mountain Inst., Snowmass, CO (United States)

    1995-12-31

    Energy efficient building and office design offers the possibility of significantly increased worker productivity. By improving lighting, heating and cooling, workers can be made more comfortable and productive. An increase of 1 percent in productivity can provide savings to a company that exceed its entire energy bill. Efficient design practices are cost effective just from their energy savings. The resulting productivity gains make them indispensable. This paper documents eight cases in which efficient lighting, heating, and cooling have measurably increased worker productivity, decreased absenteeism, and/or improved the quality of work performed. They also show that efficient lighting can measurably increase work quality by removing errors and manufacturing defects. The case studies presented include retrofit of existing buildings and the design of new facilities, and cover a variety of commercial and industrial settings. Each case study identifies the design changes that were most responsible for increased productivity. As the eight case studies illustrate, energy efficient design may be one of the least expensive ways for a business to improve the productivity of its workers and the quality of its product. (author). 15 refs.

  6. Dimensions of energy efficiency

    International Nuclear Information System (INIS)

    Ramani, K.V.

    1992-01-01

    In this address the author describes three dimensions of energy efficiency in order of increasing costs: conservation, resource and technology substitution, and changes in economic structure. He emphasizes the importance of economic rather than environmental rationales for energy efficiency improvements in developing countries. These countries do not place high priority on the problems of global climate change. Opportunities for new technologies may exist in resource transfer, new fuels and, possibly, small reactors. More research on economic and social impacts of technologies with greater sensitivity to user preferences is needed

  7. Danish Energy Efficiency Policy

    DEFF Research Database (Denmark)

    Togeby, Mikael; Larsen, Anders; Dyhr-Mikkelsen, Kirsten

    2009-01-01

    Ten groups of policy instruments for promoting energy efficiency are actively used in Denmark. Among these are the EU instruments such as the CO2 emissions trading scheme and labelling of appliances, labelling of all buildings, combined with national instruments such as high taxes especially...... of the entire Danish energy efficiency policy portfolio must be carried out before end 2008 and put forward for discussion among governing parties no later than February 2009. A consortium comprising Ea Energy Analyses, Niras, the Department of Society and Globalisation (Roskilde University) and 4-Fact...... on households and the public sector, obligations for energy companies (electricity, natural gas, district heating, and oil) to deliver documented savings, strict building codes, special instructions for the public sector, and an Electricity Saving Trust. A political agreement from 2005 states that an evaluation...

  8. Coal fires, fresh air and the hardy British: A historical view of domestic energy efficiency and thermal comfort in Britain

    International Nuclear Information System (INIS)

    Rudge, Janet

    2012-01-01

    Fuel poverty has been most commonly researched in the UK although it is experienced in other parts of Europe, to varying degrees. showed that energy inefficient buildings and heating systems are the most significant components of fuel poverty and highlighted the legacy of older buildings in this country that remain the majority of those now recognised as hard to treat. This paper considers the historical context for fuel poverty as a particularly British phenomenon. It examines claims that this is due to the mild climate and low indoor temperature expectations. It is concluded that there are significant differences from the European situation. The climate, particularly its characteristic changeability, has influenced building and heating methods, and the low priority given to energy efficiency by legislators. Significantly, economic priorities produced poor quality mass housing during the industrial revolution. The availability of coal encouraged the use of open fires, which demanded high ventilation rates. The British do value warmth but older buildings designed for heating with radiant open fires are difficult to adapt to convective central heating. Lessons can be drawn for newly industrialised economies similarly producing poor quality mass housing with low priorities for energy efficiency. - Highlights: ► Historical reasons for fuel poverty as a particularly UK phenomenon are considered. ► There are significant differences with the European situation. ► The changeable climate influenced building and heating methods as well as health. ► Fuel supply encouraged heating by inefficient open fires that needed draughts. ► Improving airtightness in an oldhousing stock remains challenging.

  9. Energy Efficiency Project Development

    Energy Technology Data Exchange (ETDEWEB)

    IUEP

    2004-03-01

    The International Utility Efficiency Partnerships, Inc. (IUEP) has been a leader among the industry groups that have supported voluntary initiatives to promote international energy efficiency projects and address global climate change. The IUEP maintains its leadership by both supporting international greenhouse gas (GHG) reduction projects under the auspices of the U.S. Department of Energy (DOE) and by partnering with U.S. and international organizations to develop and implement strategies and specific energy efficiency projects. The goals of the IUEP program are to (1) provide a way for U.S. industry to maintain a leadership role in international energy efficiency infrastructure projects; (2) identify international energy project development opportunities to continue its leadership in supporting voluntary market-based mechanisms to reduce GHG emissions; and (3) demonstrate private sector commitment to voluntary approaches to global climate issues. The IUEP is dedicated to identifying, promoting, managing, and assisting in the registration of international energy efficiency projects that result in demonstrated voluntary reductions of GHG emissions. This Final Technical Report summarizes the IUEP's work in identifying, promoting, managing, and assisting in development of these projects and IUEP's effort in creating international cooperative partnerships to support project development activities that develop and deploy technologies that (1) increase efficiency in the production, delivery and use of energy; (2) increase the use of cleaner, low-carbon fuels in processing products; and (3) capture/sequester carbon gases from energy systems. Through international cooperative efforts, the IUEP intends to strengthen partnerships for energy technology innovation and demonstration projects capable of providing cleaner energy in a cost-effective manner. As detailed in this report, the IUEP met program objectives and goals during the reporting period January 1

  10. Modelling study, efficiency analysis and optimisation of large-scale Adiabatic Compressed Air Energy Storage systems with low-temperature thermal storage

    International Nuclear Information System (INIS)

    Luo, Xing; Wang, Jihong; Krupke, Christopher; Wang, Yue; Sheng, Yong; Li, Jian; Xu, Yujie; Wang, Dan; Miao, Shihong; Chen, Haisheng

    2016-01-01

    Highlights: • The paper presents an A-CAES system thermodynamic model with low temperature thermal energy storage integration. • The initial parameter value ranges for A-CAES system simulation are identified from the study of a CAES plant in operation. • The strategies of system efficiency improvement are investigated via a parametric study with a sensitivity analysis. • Various system configurations are discussed for analysing the efficiency improvement potentials. - Abstract: The key feature of Adiabatic Compressed Air Energy Storage (A-CAES) is the reuse of the heat generated from the air compression process at the stage of air expansion. This increases the complexity of the whole system since the heat exchange and thermal storage units must have the capacities and performance to match the air compression/expansion units. Thus it raises a strong demand in the whole system modelling and simulation tool for A-CAES system optimisation. The paper presents a new whole system mathematical model for A-CAES with simulation implementation and the model is developed with consideration of lowing capital cost of the system. The paper then focuses on the study of system efficiency improvement strategies via parametric analysis and system structure optimisation. The paper investigates how the system efficiency is affected by the system component performance and parameters. From the study, the key parameters are identified, which give dominant influences in improving the system efficiency. The study is extended onto optimal system configuration and the recommendations are made for achieving higher efficiency, which provides a useful guidance for A-CAES system design.

  11. Energy efficiency in pumps

    Energy Technology Data Exchange (ETDEWEB)

    Kaya, Durmus; Yagmur, E. Alptekin [TUBITAK-MRC, P.O. Box 21, 41470 Gebze, Kocaeli (Turkey); Yigit, K. Suleyman; Eren, A. Salih; Celik, Cenk [Engineering Faculty, Kocaeli University, Kocaeli (Turkey); Kilic, Fatma Canka [Department of Air Conditioning and Refrigeration, Kocaeli University, Kullar, Kocaeli (Turkey)

    2008-06-15

    In this paper, ''energy efficiency'' studies, done in a big industrial facility's pumps, are reported. For this purpose; the flow rate, pressure and temperature have been measured for each pump in different operating conditions and at maximum load. In addition, the electrical power drawn by the electric motor has been measured. The efficiencies of the existing pumps and electric motor have been calculated by using the measured data. Potential energy saving opportunities have been studied by taking into account the results of the calculations for each pump and electric motor. As a conclusion, improvements should be made each system. The required investment costs for these improvements have been determined, and simple payback periods have been calculated. The main energy saving opportunities result from: replacements of the existing low efficiency pumps, maintenance of the pumps whose efficiencies start to decline at certain range, replacements of high power electric motors with electric motors that have suitable power, usage of high efficiency electric motors and elimination of cavitation problems. (author)

  12. Energy efficiency in pumps

    International Nuclear Information System (INIS)

    Kaya, Durmus; Yagmur, E. Alptekin; Yigit, K. Suleyman; Kilic, Fatma Canka; Eren, A. Salih; Celik, Cenk

    2008-01-01

    In this paper, 'energy efficiency' studies, done in a big industrial facility's pumps, are reported. For this purpose; the flow rate, pressure and temperature have been measured for each pump in different operating conditions and at maximum load. In addition, the electrical power drawn by the electric motor has been measured. The efficiencies of the existing pumps and electric motor have been calculated by using the measured data. Potential energy saving opportunities have been studied by taking into account the results of the calculations for each pump and electric motor. As a conclusion, improvements should be made each system. The required investment costs for these improvements have been determined, and simple payback periods have been calculated. The main energy saving opportunities result from: replacements of the existing low efficiency pumps, maintenance of the pumps whose efficiencies start to decline at certain range, replacements of high power electric motors with electric motors that have suitable power, usage of high efficiency electric motors and elimination of cavitation problems

  13. Energy efficiency labelling

    Energy Technology Data Exchange (ETDEWEB)

    1978-04-01

    This research assesses the likely effects on UK consumers of the proposed EEC energy-efficiency labeling scheme. Unless (or until) an energy-labeling scheme is introduced, it is impossible to do more than postulate its likely effects on consumer behavior. This report shows that there are indeed significant differences in energy consumption between different brands and models of the same appliance of which consumers are unaware. Further, the report suggests that, if a readily intelligible energy-labeling scheme were introduced, it would provide useful information that consumers currently lack; and that, if this information were successfully presented, it would be used and could have substantial effects in reducing domestic fuel consumption. Therefore, it is recommended that an energy labeling scheme be introduced.

  14. Phase Change Materials for Thermal Energy Storage

    OpenAIRE

    Stiebra, L; Cabulis, U; Knite, M

    2014-01-01

    Phase change materials (PCMs) for thermal energy storage (TES) have become an important subject of research in recent years. Using PCMs for thermal energy storage provides a solution to increase the efficiency of the storage and use of energy in many domestic and industrial sectors. Phase change TES systems offer a number of advantages over other systems (e.g. chemical storage systems): particularly small temperature distance between the storage and retrieval cycles, small unit sizes and lo...

  15. Energy efficient data centers

    Energy Technology Data Exchange (ETDEWEB)

    Tschudi, William; Xu, Tengfang; Sartor, Dale; Koomey, Jon; Nordman, Bruce; Sezgen, Osman

    2004-03-30

    Data Center facilities, prevalent in many industries and institutions are essential to California's economy. Energy intensive data centers are crucial to California's industries, and many other institutions (such as universities) in the state, and they play an important role in the constantly evolving communications industry. To better understand the impact of the energy requirements and energy efficiency improvement potential in these facilities, the California Energy Commission's PIER Industrial Program initiated this project with two primary focus areas: First, to characterize current data center electricity use; and secondly, to develop a research ''roadmap'' defining and prioritizing possible future public interest research and deployment efforts that would improve energy efficiency. Although there are many opinions concerning the energy intensity of data centers and the aggregate effect on California's electrical power systems, there is very little publicly available information. Through this project, actual energy consumption at its end use was measured in a number of data centers. This benchmark data was documented in case study reports, along with site-specific energy efficiency recommendations. Additionally, other data center energy benchmarks were obtained through synergistic projects, prior PG&E studies, and industry contacts. In total, energy benchmarks for sixteen data centers were obtained. For this project, a broad definition of ''data center'' was adopted which included internet hosting, corporate, institutional, governmental, educational and other miscellaneous data centers. Typically these facilities require specialized infrastructure to provide high quality power and cooling for IT equipment. All of these data center types were considered in the development of an estimate of the total power consumption in California. Finally, a research ''roadmap'' was developed

  16. Review of Strategies for Thermal Efficiency in Landscape Planning of Cities for Conservation of Energy and Enhanced Climatic Resilience to Urban Warming

    Science.gov (United States)

    Imam, Aabshar U. K.; Banerjee, Uttam Kumar

    2017-09-01

    Thermal discomfort, increased energy consumption, and heat related stress are some of the most prominent consequences of urban warming. Instances of heat related deaths have been reported; the elderly and the poor remain especially vulnerable. Urban greening has often been cited as an economically efficient method for inducing ambient cooling. Consequently, increased impetus is given to provision of public green spaces. However, a general increase in urban green cover especially in the form of parks and green spaces may be inadequate to achieve desired results. This article serves to highlight the thermal heterogeneity of landcape elements and stresses on the need for strategic shade provision. The originality of this study lies in the fact that it provides a comparative review of energy conservation potential of public and private green spaces. It is found that large parks may not have substantial cooling effect on the indoor built environment. Moreover, people tend to spend more time indoors than outdoors. Thus the need for greening of private areas has become an undeniable climatic necessity. The potential of shade trees, green walls, and roof gardens for cooling of built environment are discussed with quantitative evidences of their thermal and economic benefits. Parameters incurring cost expenditure and weaknesses of the greening strategies are enumerated for enabling prudent selection/implementation of strategies. Proposals are generated to improve climatic resilience to urban warming and for diligent planning of cities.

  17. Waste energy harvesting mechanical and thermal energies

    CERN Document Server

    Ling Bing, Kong; Hng, Huey Hoon; Boey, Freddy; Zhang, Tianshu

    2014-01-01

    Waste Energy Harvesting overviews the latest progress in waste energy harvesting technologies, with specific focusing on waste thermal mechanical energies. Thermal energy harvesting technologies include thermoelectric effect, storage through phase change materials and pyroelectric effect. Waste mechanical energy harvesting technologies include piezoelectric (ferroelectric) effect with ferroelectric materials and nanogenerators. The book aims to strengthen the syllabus in energy, materials and physics and is well suitable for students and professionals in the fields.

  18. Thermal efficiency of a non-transferred thermal plasma cannon

    International Nuclear Information System (INIS)

    Mercado, A.; Cota, G.; Merlo, L.; Pacheco, J.; Pena, R.; Cruz, A.

    1997-01-01

    This work shows a thermal efficiency research (ν) for a plasma torch in d.c. which was carried out through the realization of an energy balance around the system under consideration. The plasma torch is manufactured in copper with a tungsten incrustations in cathode. The gas used was argon and the gas fluxes were at the rank of 10 and 40 lt/min to the total pressure of 1.2 bar (1.1 atm). With these conditions it was worked with electric currents at the rank of 40 and 180 A. The data were collected through a data acquisition card which was programmed in Windows environment. (Author)

  19. Using energy efficiently

    International Nuclear Information System (INIS)

    Nipkow, J.; Brunner, C. U.

    2005-01-01

    This comprehensive article discusses the perspectives for reducing electricity consumption in Switzerland. The increase in consumption is discussed that has occurred in spite of the efforts of the Swiss national energy programmes 'Energy 2000' and 'SwissEnergy'. The fact that energy consumption is still on the increase although efficient and economically-viable technology is available is commented on. The authors are of the opinion that the market alone cannot provide a complete solution and that national and international efforts are needed to remedy things. In particular, the external costs that are often not included when estimating costs are stressed. Several technical options available, such as the use of fluorescent lighting, LCD monitors and efficient electric motors, are looked at as are other technologies quoted as being a means of reducing power consumption. Ways of reducing stand-by losses and system optimisation are looked at as are various scenarios for further development and measures that can be implemented in order to reduce power consumption

  20. Energy efficiency fallacies revisited

    International Nuclear Information System (INIS)

    Brookes, Leonard

    2000-01-01

    A number of governments including that of the UK subscribe to the belief that a national program devoted to raising energy efficiency throughout the economy provides a costless - indeed profitable - route to meeting international environmental obligations. This is a seductive policy. It constitutes the proverbial free lunch - not only avoiding politically unpopular measures like outlawing, taxing or rationing offending fuels or expanding non-carboniferous sources of energy like nuclear power but doing so with economic benefit. The author of this contribution came to doubt the validity of this solution when it was offered as a way of mitigating the effect of the OPEC price hikes of the 1970s, maintaining that economically justified improvement in energy efficiency led to higher levels of energy consumption at the economy-wide level than in the absence of any efficiency response. More fundamentally, he argues that there is no case for preferentially singling out energy, from among all the resources available to us, for efficiency maximisation. The least damaging policy is to determine targets, enact the restrictive measures needed to curb consumption, and then leave it to consumers - intermediate and final - to reallocate all the resources available to them to best effect subject to the new enacted constraints and any others they might be experiencing. There is no reason to suppose that it is right for all the economic adjustment following a new resource constraint to take the form of improvements in the productivity of that resource alone. As many others have argued, any action to impose resource constraint entails an inevitable economic cost in the shape of a reduction in production and consumption possibilities: there would be no free lunch. In the last few years debate about the validity of these contentions has blossomed, especially under the influence of writers on the western side of the Atlantic. In this contribution the author outlines the original arguments

  1. Hybrid energy harvesting using active thermal backplane

    Science.gov (United States)

    Kim, Hyun-Wook; Lee, Dong-Gun

    2016-04-01

    In this study, we demonstrate the concept of a new hybrid energy harvesting system by combing solar cells with magneto-thermoelectric generator (MTG, i.e., thermal energy harvesting). The silicon solar cell can easily reach high temperature under normal operating conditions. Thus the heated solar cell becomes rapidly less efficient as the temperature of solar cell rises. To increase the efficiency of the solar cell, air or water-based cooling system is used. To surpass conventional cooling devices requiring additional power as well as large working space for air/water collectors, we develop a new technology of pairing an active thermal backplane (ATB) to solar cell. The ATB design is based on MTG technology utilizing the physics of the 2nd order phase transition of active ferromagnetic materials. The MTG is cost-effective conversion of thermal energy to electrical energy and is fundamentally different from Seebeck TEG devices. The ATB (MTG) is in addition to being an energy conversion system, a very good conveyor of heat through both conduction and convection. Therefore, the ATB can provide dual-mode for the proposed hybrid energy harvesting. One is active convective and conductive cooling for heated solar cell. Another is active thermal energy harvesting from heat of solar cell. These novel hybrid energy harvesting device have potentially simultaneous energy conversion capability of solar and thermal energy into electricity. The results presented can be used for better understanding of hybrid energy harvesting system that can be integrated into commercial applications.

  2. Thermal efficiency improvements - an imperative for nuclear generating stations

    International Nuclear Information System (INIS)

    Hassanien, S.; Rouse, S.

    1997-01-01

    A one and a half percent thermal performance improvement of Ontario Hydro's operating nuclear units (Bruce B, Pickering B, and Darlington) means almost 980 GWh are available to the transmission system (assuming an 80% capacity factor). This is equivalent to the energy consumption of 34,000 electrically-heated homes in Ontario, and worth more than $39 million in revenue to Ontario Hydro Nuclear Generation. Improving nuclear plant thermal efficiency improves profitability (more GWh per unit of fuel) and competitiveness (cost of unit energy), and reduces environmental impact (less spent fuel and nuclear waste). Thermal performance will naturally decrease due to the age of the units unless corrective action is taken. Most Ontario Hydro nuclear units are ten to twenty years old. Some common causes for loss of thermal efficiency are: fouling and tube plugging of steam generators, condensers, and heat exchangers; steam leaks in the condenser due to valve wear, steam trap and drain leaks; deposition, pitting, cracking, corrosion, etc., of turbine blades; inadequate feedwater metering resulting from corrosion and deposition. This paper stresses the importance of improving the nuclear units' thermal efficiency. Ontario Hydro Nuclear has demonstrated energy savings results are achievable and affordable. Between 1994 and 1996, Nuclear reduced its energy use and improved thermal efficiency by over 430,000 MWh. Efficiency improvement is not automatic - strategies are needed to be effective. This paper suggests practical strategies to systematically improve thermal efficiency. (author)

  3. Measures for energy efficiency improvement of buildings

    Directory of Open Access Journals (Sweden)

    Vukadinović Ana V.

    2015-01-01

    Full Text Available The increase in energy consumption in buildings causes the need to propose energy efficiency improvement measures. Urban planning in accordance with micro location conditions can lead to energy consumption reduction in buildings through the passive solar design. While satisfying the thermal comfort to the user space purpose, energy efficiency can be achieved by optimizing the architectural and construction parameters such as shape of the building, envelope structure and the percentage of glazing. The improvement of the proposed measures, including the use of renewable energy sources, can meet requirements of Directive 2010/31 / EU of 'nearly zero energy buildings'.

  4. Renewable energy sources: Energy Efficiency Agency

    International Nuclear Information System (INIS)

    Bulgarensky, Mihael

    2004-01-01

    The paper presents the activities of the Energy Efficiency Agency, its main functions, as well as the new legislation stimulating the use of RES, stipulated in the new Energy Law of Bulgaria. The second part of the paper describes the potential of renewable energy in i.e. wind energy; solar energy; biomass energy; hydro energy; geothermal energy; draft of a National Program on RES 2005-2015. The third part describes the main issues of the new ENERGY EFFICIENCY LAW and the established Energy efficiency fund. (Author)

  5. Energy Efficient Mobile Operating Systems

    OpenAIRE

    Muhammad Waseem

    2013-01-01

    Energy is an important resource in mobile computers now days. It is important to manage energy in efficient manner so that energy consumption will be reduced. Developers of operating system decided to increase the battery life time of mobile phones at operating system level. So, design of energy efficient mobile operating system is the best way to reduce the energy consumption in mobile devices. In this paper, currently used energy efficient mobile operating system is discussed and compared. ...

  6. Manipulating the Electronic Excited State Energies of Pyrimidine-Based Thermally Activated Delayed Fluorescence Emitters To Realize Efficient Deep-Blue Emission.

    Science.gov (United States)

    Komatsu, Ryutaro; Ohsawa, Tatsuya; Sasabe, Hisahiro; Nakao, Kohei; Hayasaka, Yuya; Kido, Junji

    2017-02-08

    The development of efficient and robust deep-blue emitters is one of the key issues in organic light-emitting devices (OLEDs) for environmentally friendly, large-area displays or general lighting. As a promising technology that realizes 100% conversion from electrons to photons, thermally activated delayed fluorescence (TADF) emitters have attracted considerable attention. However, only a handful of examples of deep-blue TADF emitters have been reported to date, and the emitters generally show large efficiency roll-off at practical luminance over several hundreds to thousands of cd m -2 , most likely because of the long delayed fluorescent lifetime (τ d ). To overcome this problem, we molecularly manipulated the electronic excited state energies of pyrimidine-based TADF emitters to realize deep-blue emission and reduced τ d . We then systematically investigated the relationships among the chemical structure, properties, and device performances. The resultant novel pyrimidine emitters, called Ac-XMHPMs (X = 1, 2, and 3), contain different numbers of bulky methyl substituents at acceptor moieties, increasing the excited singlet (E S ) and triplet state (E T ) energies. Among them, Ac-3MHPM, with a high E T of 2.95 eV, exhibited a high external quantum efficiency (η ext,max ) of 18% and an η ext of 10% at 100 cd m -2 with Commission Internationale de l'Eclairage chromaticity coordinates of (0.16, 0.15). These efficiencies are among the highest values to date for deep-blue TADF OLEDs. Our molecular design strategy provides fundamental guidance to design novel deep-blue TADF emitters.

  7. ENERGY EFFICIENT DESALINATOR

    Directory of Open Access Journals (Sweden)

    T. A. Ismailov

    2017-01-01

    Full Text Available Objectives. The aim of the research is to develop a thin-film semiconductor thermoelectric heat pump of cylindrical shape for the desalination of sea water.Methods. To improve the efficiency of the desalination device, a  special thin-film semiconductor thermoelectric heat pump of  cylindrical shape is developed. The construction of the thin-film  semiconductor thermoelectric heat pump allows the flow rates of  incoming sea water and outflowing fresh water and brine to be  equalised by changing the geometric dimensions of the desalinator.  The cross-sectional area of the pipeline for incoming sea water is equal to the total area of outflowing fresh water and brine.Results. The use of thin-film semiconductor p- and n-type branches  in a thermo-module reduces their electrical resistance virtually to  zero and completely eliminates Joule's parasitic heat release. The  Peltier thermoelectric effect on heating and cooling is completely  preserved, bringing the efficiency of the heat pump to almost 100%, improving the energy-saving characteristics of the  desalinator as a whole. To further increase the efficiency of the  proposed desalinator, thermoelectric modules with radiation can be  used as thermoelectric devices.Conclusion. As a consequence of the creation of conditions of high rarefaction under which water will be converted to steam, which, at  20° C, is cold (as is the condensed distilled water, energy costs can  be reduced. In this case, the energy for heating and cooling is not  wasted; moreover, sterilisation is also achieved using the ultraviolet  radiation used in the thermoelectric devices, which, on the one hand, generate electromagnetic ultraviolet radiation, and, on the other, cooling. Such devices operate in optimal mode without heat  release. The desalination device can be used to produce fresh water and concentrated solutions from any aqueous solutions, including wastewater from industrial

  8. Energy efficiency in Swedish industry

    International Nuclear Information System (INIS)

    Zhang, Shanshan; Lundgren, Tommy; Zhou, Wenchao

    2016-01-01

    This paper assesses energy efficiency in Swedish industry. Using unique firm-level panel data covering the years 2001–2008, the efficiency estimates are obtained for firms in 14 industrial sectors by using data envelopment analysis (DEA). The analysis accounts for multi-output technologies where undesirable outputs are produced alongside with the desirable output. The results show that there was potential to improve energy efficiency in all the sectors and relatively large energy inefficiencies existed in small energy-use industries in the sample period. Also, we assess how the EU ETS, the carbon dioxide (CO_2) tax and the energy tax affect energy efficiency by conducting a second-stage regression analysis. To obtain consistent estimates for the regression model, we apply a modified, input-oriented version of the double bootstrap procedure of Simar and Wilson (2007). The results of the regression analysis reveal that the EU ETS and the CO_2 tax did not have significant influences on energy efficiency in the sample period. However, the energy tax had a positive relation with the energy efficiency. - Highlights: • We use DEA to estimate firm-level energy efficiency in Swedish industry. • We examine impacts of climate and energy policies on energy efficiency. • The analyzed policies are Swedish carbon and energy taxes and the EU ETS. • Carbon tax and EU ETS did not have significant influences on energy efficiency. • The energy tax had a positive relation with energy efficiency.

  9. Energy efficient solid state lighting

    Energy Technology Data Exchange (ETDEWEB)

    Dam-Hansen, C.; Petersen, Poul Michael

    2012-11-15

    Even though vast improvements have been made on efficiency and light quality, SSL is still in its infancy. One of the barriers for a market introduction is the price, which still is around 5 times higher than traditional lighting technologies. In order to fulfil the potential of SSL, further research and development needs to increase the light extraction from semiconductor materials, provide better and cheaper production and packaging, and advanced optical systems for optimized light distribution and new thermal solutions for SSL lamps and luminaires. Nanotechnology and applied research at DTU Fotonik in close collaboration with industry are essential parts in the development of new enhanced LED optical systems and LEDs with higher light extraction efficiency. Photonic crystals can help to efficiently extract light from LEDs and to form a desired emission profile. Future directions are devoted to the next generation of LEDs, in which the spontaneous emission is photon enhanced. One realization of this idea is using LEDs with a layer of nanocrystals, which are coupled to the quantum well of the LED. Such R and D work is ongoing all over the world and DOE roadmaps foresee luminous efficiencies by 2020 that are close to 250 lm/W for both cold and warm white light from LEDs, and prices in the order of one dollar per kilolumen. Such figures will drastically reduce the energy consumption worldwide for lighting, and hence a marked reduction in carbon emissions. (Author)

  10. Energy Efficiency in Swimming Facilities

    OpenAIRE

    Kampel, Wolfgang

    2015-01-01

    High and increasing energy use is a worldwide issue that has been reported and documented in the literature. Various studies have been performed on renewable energy and energy efficiency to counteract this trend. Although using renewable energy sources reduces pollution, improvements in energy efficiency reduce total energy use and protect the environment from further damage. In Europe, 40 % of the total energy use is linked to buildings, making them a main objective concerning...

  11. Thermal energy at the nanoscale

    CERN Document Server

    Fisher, Timothy S

    2014-01-01

    These lecture notes provide a detailed treatment of the thermal energy storage and transport by conduction in natural and fabricated structures. Thermal energy in two carriers, i.e. phonons and electrons -- are explored from first principles. For solid-state transport, a common Landauer framework is used for heat flow. Issues including the quantum of thermal conductance, ballistic interface resistance, and carrier scattering are elucidated. Bulk material properties, such as thermal and electrical conductivity, are derived from particle transport theories, and the effects of spatial confinement on these properties are established. Readership: Students and professionals in physics and engineering.

  12. A novel thermally driven rotor-vane/pressure-exchange ejector refrigeration system with environmental benefits and energy efficiency

    International Nuclear Information System (INIS)

    Hong, W.J.; Alhussan, Khaled; Zhang Hongfang; Garris, Charles A.

    2004-01-01

    The latest results of an ongoing coordinated experimental and computational program on the design and performance of a novel supersonic rotor-vane/pressure-exchange ejector for thermally driven ejector refrigeration systems are presented. For the supersonic rotor-vane/pressure-exchange ejector, careful management of the entropy rise through the oblique shocks and boundary layers is required for obtaining an advance in ejector performance. Since the invention of this new ejector is quite recent, understanding its aerodynamics, with the consequent optimization of performance, is in the formative stage. This paper shows how the supersonic aerodynamics is managed to provide the desirable flow induction characteristics through computational study and, in parallel, experimental results including flow visualization showing actual behavior with different-shaped rotor vanes. The importance of the existence of the tail part with a long expansion ramp, the sharp leading edge such as knife-edge, the proper height of leading edges, for the overall shape of rotor vane, were observed. Also the larger spin-angle rotor vane produces better flow induction and mixing between primary flow and secondary flow

  13. Efficient thermal diode with ballistic spacer

    Science.gov (United States)

    Chen, Shunda; Donadio, Davide; Benenti, Giuliano; Casati, Giulio

    2018-03-01

    Thermal rectification is of importance not only for fundamental physics, but also for potential applications in thermal manipulations and thermal management. However, thermal rectification effect usually decays rapidly with system size. Here, we show that a mass-graded system, with two diffusive leads separated by a ballistic spacer, can exhibit large thermal rectification effect, with the rectification factor independent of system size. The underlying mechanism is explained in terms of the effective size-independent thermal gradient and the match or mismatch of the phonon bands. We also show the robustness of the thermal diode upon variation of the model's parameters. Our finding suggests a promising way for designing realistic efficient thermal diodes.

  14. Functional materials for energy-efficient buildings

    Science.gov (United States)

    Ebert, H.-P.

    2015-08-01

    The substantial improving of the energy efficiency is essential to meet the ambitious energy goals of the EU. About 40% of the European energy consumption belongs to the building sector. Therefore the reduction of the energy demand of the existing building stock is one of the key measures to deliver a substantial contribution to reduce CO2-emissions of our society. Buildings of the future have to be efficient in respect to energy consumption for construction and operation. Current research activities are focused on the development of functional materials with outstanding thermal and optical properties to provide, for example, slim thermally superinsulated facades, highly integrated heat storage systems or adaptive building components. In this context it is important to consider buildings as entities which fulfill energy and comfort claims as well as aesthetic aspects of a sustainable architecture.

  15. Functional materials for energy-efficient buildings

    Directory of Open Access Journals (Sweden)

    Ebert H.-P

    2015-01-01

    Full Text Available The substantial improving of the energy efficiency is essential to meet the ambitious energy goals of the EU. About 40% of the European energy consumption belongs to the building sector. Therefore the reduction of the energy demand of the existing building stock is one of the key measures to deliver a substantial contribution to reduce CO2-emissions of our society. Buildings of the future have to be efficient in respect to energy consumption for construction and operation. Current research activities are focused on the development of functional materials with outstanding thermal and optical properties to provide, for example, slim thermally superinsulated facades, highly integrated heat storage systems or adaptive building components. In this context it is important to consider buildings as entities which fulfill energy and comfort claims as well as aesthetic aspects of a sustainable architecture.

  16. Ocean Thermal Extractable Energy Visualization

    Energy Technology Data Exchange (ETDEWEB)

    Ascari, Matthew [Lockheed Martin Corporation, Bethesda, MD (United States)

    2012-10-28

    The Ocean Thermal Extractable Energy Visualization (OTEEV) project focuses on assessing the Maximum Practicably Extractable Energy (MPEE) from the world’s ocean thermal resources. MPEE is defined as being sustainable and technically feasible, given today’s state-of-the-art ocean energy technology. Under this project the OTEEV team developed a comprehensive Geospatial Information System (GIS) dataset and software tool, and used the tool to provide a meaningful assessment of MPEE from the global and domestic U.S. ocean thermal resources.

  17. How energy efficient is your car?

    Science.gov (United States)

    Roura, Pere; Oliu, Daniel

    2012-07-01

    A detailed energy balance indicating how fuel energy is transferred from the engine to the wheels of a commercial car is obtained using non-specialized experiments that can be readily understood using elementary mechanics. These experiments allow us to determine the engine's thermal efficiency, its mechanical losses, and the rolling (friction) and aerodynamic (drag) coefficients. We find that approximately 28% of the fuel energy is transferred to the wheels.

  18. Advanced Energy Efficient Roof System

    Energy Technology Data Exchange (ETDEWEB)

    Jane Davidson

    2008-09-30

    Energy consumption in buildings represents 40 percent of primary U.S. energy consumption, split almost equally between residential (22%) and commercial (18%) buildings.1 Space heating (31%) and cooling (12%) account for approximately 9 quadrillion Btu. Improvements in the building envelope can have a significant impact on reducing energy consumption. Thermal losses (or gains) from the roof make up 14 percent of the building component energy load. Infiltration through the building envelope, including the roof, accounts for an additional 28 percent of the heating loads and 16 percent of the cooling loads. These figures provide a strong incentive to develop and implement more energy efficient roof systems. The roof is perhaps the most challenging component of the building envelope to change for many reasons. The engineered roof truss, which has been around since 1956, is relatively low cost and is the industry standard. The roof has multiple functions. A typical wood frame home lasts a long time. Building codes vary across the country. Customer and trade acceptance of new building products and materials may impede market penetration. The energy savings of a new roof system must be balanced with other requirements such as first and life-cycle costs, durability, appearance, and ease of construction. Conventional residential roof construction utilizes closely spaced roof trusses supporting a layer of sheathing and roofing materials. Gypsum board is typically attached to the lower chord of the trusses forming the finished ceiling for the occupied space. Often in warmer climates, the HVAC system and ducts are placed in the unconditioned and otherwise unusable attic. High temperature differentials and leaky ducts result in thermal losses. Penetrations through the ceilings are notoriously difficult to seal and lead to moisture and air infiltration. These issues all contribute to greater energy use and have led builders to consider construction of a conditioned attic. The

  19. Energy efficiency and greenhouse gases

    International Nuclear Information System (INIS)

    Hamburg, A.; Martins, A.; Pesur, A.; Roos, I.

    1996-01-01

    Estonia's energy balance for 1990 - 1994 is characterized by the dramatic changes in the economy after regaining independence in 1991. In 1990 - 1993, primary energy supply decreased about 1.9 times. The reasons were a sharp decrease in exports of electric energy and industrial products, a steep increase in fuel prices and the transition from the planned to a market-oriented economy. Over the same period, the total amount of emitted greenhouse gases decreased about 45%. In 1993, the decrease in energy production and consumption stopped, and in 1994, a moderate increase occurred (about 6%), which is a proof stabilizing economy. Oil shale power engineering will remain the prevailing energy resource for the next 20 - 25 years. After stabilization, the use of oil shale will rise in Estonia's economy. Oil shale combustion in power plants will be the greatest source of greenhouse gases emissions in near future. The main problem is to decrease the share of CO 2 emissions from the decomposition of carbonate part of oil shale. This can be done by separating limestone particles from oil shale before its burning by use of circulating fluidized bed combustion technology. Higher efficiency of oil shale power plants facilitates the reduction of CO 2 emissions per generated MWh electricity considerably. The prognoses for the future development of power engineering depend essentially on the environmental requirements. Under the highly restricted development scenario, which includes strict limitations to emissions (CO 2 , SO 2 , thermal waste) and a severe penalty system, the competitiveness of nuclear power will increase. The conceptual steps taken by the Estonian energy management should be in compliance with those of neighboring countries, including the development programs of the other Baltic states

  20. Improving Thermal and Electrical Efficiency in Photovoltaic Thermal Systems for Sustainable Cooling System Integration

    Directory of Open Access Journals (Sweden)

    Mohammad Alobaid

    2018-06-01

    Full Text Available Research into photovoltaic thermal systems is important in solar technologies as photovoltaic thermal systems are designed to produce both electrical and thermal energy, this can lead to improved performance of the overall system. The performance of photovoltaic thermal systems is based on several factors that include photovoltaic thermal materials, design, ambient temperature, inlet and outlet fluid temperature and photovoltaic cell temperature. The aim of this study is to investigate the effect of photovoltaic thermal outlet water temperatures and solar cell temperature on both electrical and thermal efficiency for different range of inlet water temperature. To achieve this, a mathematical model of a photovoltaic thermal system was developed to calculate the anticipated system performance. The factors that affect the efficiency of photovoltaic thermal collectors were discussed and the outlet fluid temperature from the photovoltaic thermal is investigated in order to reach the highest overall efficiency for the solar cooling system. An average thermal and electrical efficiency of 65% and 13.7%, respectively, was achieved and the photovoltaic thermal mathematical model was validated with experimental data from literature.

  1. Energy conservation, efficiency and energy audit

    International Nuclear Information System (INIS)

    Sharma, R.A.

    2006-01-01

    In this paper the author discusses the conservation, efficiency, audit, fundamentals, differences and methods, the objectives of energy conservation, definitions of energy audit, scope, short term, medium term and long term measures to be taken for conservation are discussed

  2. Efficiency Evaluation of Energy Systems

    CERN Document Server

    Kanoğlu, Mehmet; Dinçer, İbrahim

    2012-01-01

    Efficiency is one of the most frequently used terms in thermodynamics, and it indicates how well an energy conversion or process is accomplished. Efficiency is also one of the most frequently misused terms in thermodynamics and is often a source of misunderstanding. This is because efficiency is often used without being properly defined first. This book intends to provide a comprehensive evaluation of various efficiencies used for energy transfer and conversion systems including steady-flow energy devices (turbines, compressors, pumps, nozzles, heat exchangers, etc.), various power plants, cogeneration plants, and refrigeration systems. The book will cover first-law (energy based) and second-law (exergy based) efficiencies and provide a comprehensive understanding of their implications. It will help minimize the widespread misuse of efficiencies among students and researchers in energy field by using an intuitive and unified approach for defining efficiencies. The book will be particularly useful for a clear ...

  3. Energy efficiency: Lever for the Energy Transition

    International Nuclear Information System (INIS)

    2012-12-01

    The Eco-electric industry group (FFIE, FGME, Gimelec, IGNES, SERCE) has conducted a study to evaluate the energy saving potential of active energy efficiency solutions in the residential and commercial building sectors. Based on field implementations and demonstrators, it has been demonstrated that active energy efficiency can sustainably achieve substantial savings for households, companies and public authorities. Energy Efficiency - Lever for the energy transition presents the results and conclusions of that study, alongside with recommendations for public authority in terms of building retrofit policy for putting France on the best possible 'trajectory' from a budgetary and environmental point of view. (author)

  4. Energy efficient lighting

    International Nuclear Information System (INIS)

    Aslam, M.

    1992-01-01

    The main sources of Pakistan's energy supply are oil, natural gas, coal, hydro power, nuclear power and liquefied petroleum gas. At present 75 % of total energy delivered is met through oil and gas. The limited resources and financial constraints have proved to be stumbling block in the way of prosperity and economics stability. Lighting is a conspicuous consumer of energy and thus an easy prey for saving drives which is indeed a very promising target for energy saving. (A.B.)

  5. Energy Efficient Televisions

    DEFF Research Database (Denmark)

    Andersen, Rikke Dorothea; Remmen, Arne

    The EuP Directive sets the frame for implementing ecodesign requirements for energy-using and energy-related products. The aim of the Directive is to achieve a high level of protection for the environment by reducing the potential environmental impact of energy-related products. The focus...

  6. Energy efficiency: 2004 world overview

    International Nuclear Information System (INIS)

    2004-01-01

    Since 1992 the World Energy Council (WEC) has been collaborating with ADEME (Agency for Environment and Energy Efficiency, France) on a joint project 'Energy Efficiency Policies and Indicators'. APERC (Asia Pacific Energy Research Centre) and OLADE (Latin American Energy Organisation) have also participated in the study, which has been monitoring and evaluating energy efficiency policies and their impacts around the world. WEC Member Committees have been providing data and information and ENERDATA (France) has provided technical assistance. This report, published in August 2004, presents and evaluates energy efficiency policies in 63 countries, with a specific focus on five policy measures, for which in-depth case studies were prepared by selected experts: - Minimum energy efficiency standards for household electrical appliances; - Innovative energy efficiency funds; - Voluntary/negotiated agreements on energy efficiency/ CO 2 ; - Local energy information centres; - Packages of measures. In particular, the report identifies the policy measures, which have proven to be the most effective, and can be recommended to countries which have recently embarked on the development and implementation of energy demand management policies. During the past ten years, the Kyoto Protocol and, more recently, emerging concerns about security of supply have raised, both the public and the political profile of energy efficiency. Almost all OECD countries and an increasing number of other countries are implementing energy efficiency policies adapted to their national circumstances. In addition to the market instruments (voluntary agreements, labels, information, etc.), regulatory measures are widely introduced where the market fails to give the right signals (buildings, appliances). In developing countries, energy efficiency is equally important, even if the drivers are different compared to industrialized countries. Reduction of greenhouse gas emissions and local pollution often have a

  7. Recent development in thermally activated desalination methods: achieving an energy efficiency less than 2.5 kWhelec/m3

    KAUST Repository

    Shahzad, Muhammad Wakil

    2015-05-19

    Water-Energy-Environment nexus is a crucial consideration when designing seawater desalination processes, particularly for the water-stressed countries where the annual water availability is less than 250 m3 per capita. Despite the thermodynamics limit for seawater desalination at normal conditions is about 0.78 to 1.09 kWhelec/m3, the specific energy consumption of desalination of real plants is found to operate at several folds higher. Today’s technological advancement in membranes, namely the reverse osmosis processes, has set an energy consumption of around 3.5–5 kWhelec/m3, while the conventional perception of thermally activated processes such as MSF and MED tends to be higher. Although the higher energetic specific consumption of MED or MSF processes appeared to be higher at 60–100 kWhthermal/m3, their true electricity equivalent has been converted, hitherto, using the energetic analyses where the work potential of working steam of the processes cannot be captured adequately. Thermally activated processes, such as MED and MSF, form the bottoming cycle of a cogeneration plant where both electricity and desalination processes operate in tandem in a cascaded manner. Only the bled-steam at lower exergy is extracted for the desalination processes. In this presentation, we demonstrate that in a cogen plant with 30% bled-steam for MED processes, the exergy destruction ratio is found to be less than 7% of the total available exergy that emanated from the boilers. By the exergetic approach, the equivalent electricity consumption of an average 75 kWhthermal/m3 would result in an electrical equivalent of less than 2.5 kWhelec/m3. Also in this presentation, the authors will elaborate the latest developments in the use of hybridization concept where the MED and the AD cycles are thermodynamically integrated and enhancing the overall efficiency of desalination. © 2015 Balaban Desalination Publications. All rights reserved.

  8. Energy efficiency: utopia or reality?

    International Nuclear Information System (INIS)

    Anon.

    2006-01-01

    In its 2006 allocution the world council on the energy WEC, analyzes the role of the energy efficiency in the energy life cycle. In spite of different objectives followed by the developing and developed countries, implement a world energy efficiency economy is a challenge possible by the cooperation.The WEC is an ideal forum for the information and experience exchange. (A.L.B.)

  9. Increasing the thermal efficiency of boiler plant

    Directory of Open Access Journals (Sweden)

    Uyanchinov Evgeniy

    2017-01-01

    Full Text Available The thermal efficiency increase of boiler plant is actual task of scientific and technical researches. The optimization of boiler operating conditions is task complex, which determine by most probable average load of boiler, operating time and characteristics of the auxiliary equipment. The work purpose – the determination of thermodynamic efficiency increase ways for boiler plant with a gas-tube boiler. The tasks, solved at the research are the calculation of heat and fuel demand, the exergetic analysis of boilerhouse and heat network equipment, the determination of hydraulic losses and exergy losses due to restriction. The calculation was shown that the exergy destruction can be reduced by 2.39% due to excess air reducing to 10%; in addition the oxygen enrichment of air can be used that leads to reducing of the exergy destruction rate. The processes of carbon deposition from the side of flame and processes of scale formation on the water side leads to about 4.58% losses of fuel energy at gas-tube boiler. It was shown that the exergy losses may be reduced by 2.31% due to stack gases temperature reducing to 148 °C.

  10. USSR energy efficiency and prospects

    International Nuclear Information System (INIS)

    Sinyak, Y.

    1991-06-01

    The U.S.S.R. is the largest energy producer and the second largest energy consumer in the world. Its share of global energy use reached above 17% in 1988. The soviet energy system is characterized by low efficiency and high per capita energy consumption, although there are some reasons justifying the greater U.S.S.R. energy use per unit of product output than in other industrialized countries. The present energy-savings potential is approximately equal to one-half of the domestic energy consumption. Improvements in energy efficiency at all levels of the national economy are now considered to be the primary goal of national energy policy for the next couple of decades. Being endowed with abundant natural gas resources, the U.S.S.R. will count on this energy source in the future to improve its energy efficiency, reduce expenses and cope with air pollution. After 2005-2010, stabilized primary energy consumption may be reached or there may even be a decline of total energy use. The U.S.S.R. could reduce CO 2 emissions by 20% by 2030 but with substantial negative impacts on GNP growth. Required improvements in the Soviet energy system depend on changes in energy management, including reduction of the role of centralized planning, decentralization and privatization of energy-producing facilities, energy-price reforms, reshaping of investment patterns, reduction in military expenditures, etc. (author)

  11. Is energy efficiency environmentally friendly?

    Energy Technology Data Exchange (ETDEWEB)

    Herring, H. [Open University, Milton Keynes (United Kingdom). Energy and Environment Research Unit

    2000-07-01

    The paper challenges the view that improving the efficiency of energy use will lead to a reduction in national energy consumption, and hence is an effective policy for reducing CO{sub 2} emissions. It argues that improving energy efficiency lowers the implicit price of energy and hence makes its use more affordable, thus leading to greater use. The paper presents the views of economists, as well as green critics of 'efficiency' and the 'dematerialization' thesis. It argues that a more effective CO{sub 2} policy is to concentrate on shifting to non-fossil fuel, like renewables, subsidized through a carbon tax. Ultimately what is needed, to limit energy consumption is energy conservation not energy efficiency. 44 refs.

  12. Thermal-based modeling of coupled carbon, water, and energy fluxes using nominal light use efficiencies constrained by leaf chlorophyll observations

    KAUST Repository

    Schull, M. A.

    2015-03-11

    Recent studies have shown that estimates of leaf chlorophyll content (Chl), defined as the combined mass of chlorophyll a and chlorophyll b per unit leaf area, can be useful for constraining estimates of canopy light use efficiency (LUE). Canopy LUE describes the amount of carbon assimilated by a vegetative canopy for a given amount of absorbed photosynthetically active radiation (APAR) and is a key parameter for modeling land-surface carbon fluxes. A carbon-enabled version of the remote-sensing-based two-source energy balance (TSEB) model simulates coupled canopy transpiration and carbon assimilation using an analytical sub-model of canopy resistance constrained by inputs of nominal LUE (βn), which is modulated within the model in response to varying conditions in light, humidity, ambient CO2 concentration, and temperature. Soil moisture constraints on water and carbon exchange are conveyed to the TSEB-LUE indirectly through thermal infrared measurements of land-surface temperature. We investigate the capability of using Chl estimates for capturing seasonal trends in the canopy βn from in situ measurements of Chl acquired in irrigated and rain-fed fields of soybean and maize near Mead, Nebraska. The results show that field-measured Chl is nonlinearly related to βn, with variability primarily related to phenological changes during early growth and senescence. Utilizing seasonally varying βn inputs based on an empirical relationship with in situ measured Chl resulted in improvements in carbon flux estimates from the TSEB model, while adjusting the partitioning of total water loss between plant transpiration and soil evaporation. The observed Chl-βn relationship provides a functional mechanism for integrating remotely sensed Chl into the TSEB model, with the potential for improved mapping of coupled carbon, water, and energy fluxes across vegetated landscapes.

  13. 78 FR 48855 - Renewable Energy and Energy Efficiency Advisory Committee

    Science.gov (United States)

    2013-08-12

    ... Administration Renewable Energy and Energy Efficiency Advisory Committee AGENCY: International Trade... the international competitiveness of the U.S. renewable energy and energy efficiency industries. The... Renewable Energy and Energy Efficiency Advisory Committee, Attention: Ryan Mulholland, Office of Energy and...

  14. Romania needs a strategy for thermal energy

    Directory of Open Access Journals (Sweden)

    Leca Aureliu

    2015-06-01

    Full Text Available The energy sector in Romania consists of three sub-sectors: electricity, natural gas and heat. Among these, the sub-sector of thermal energy is in the most precarious situation because it has been neglected for a long time. This sub-sector is particularly important both due to the amount of final heat consumption (of over 50% of final energy consumption, and to the fact that it has a direct negative effect on the population, industry and services. This paper presents the main directions for developing a modern strategy of the thermal energy sub-sector, which would fit into Romania’s Energy Strategy that is still in preparation This is based on the author’s 50 years of experience in this field that includes knowledge about the processes and the equipment of thermal energy, expertise in the management and restructuring of energy companies and also knowledge of the specific legislation. It is therefore recommended, following the European regulations and practices, the promotion and upgrading of district heating systems using efficient cogeneration, using trigeneration in Romania, modernizing buildings in terms of energy use, using of renewable energy sources for heating, especially biomass, and modernizing the energy consumption of rural settlements.

  15. Thermodynamic analysis of thermal efficiency and power of Minto engine

    International Nuclear Information System (INIS)

    He, Wei; Hou, Jingxin; Zhang, Yang; Ji, Jie

    2011-01-01

    Minto engine is a kind of liquid piston heat engine that operates on a small temperature gradient. But there is no power formula for it yet. And its thermal efficiency is low and formula sometimes is misused. In this paper, deriving the power formula and simplifying the thermal efficiency formula of Minto engine based on energy distribution analysis will be discussed. To improve the original Minto engine, a new design of improved Minto engine is proposed and thermal efficiency formula and power formula are also given. A computer program was developed to analyze thermal efficiency and power of original and improved Minto engines operating between low and high-temperature heat sources. The simulation results show that thermal efficiency of improved Minto engine can reach over 7% between 293.15 K and 353.15 K which is much higher than that of original one; the temperature difference between upper and lower containers is lower than half of that between low and high temperature of heat sources when the original Minto engines output the maximum power; on the contrary, it is higher in the improved Minto engines. -- Highlights: ► The thermal efficiency formula of Minto engine is simplified and the power formula is established. ► A high-powered design of improved Minto engine is proposed. ► A computer simulation program based on real operating environment is developed.

  16. Energy efficiency policies and measures

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    This document makes a review of the energy efficiency and demand side management (DSM) policies and measures in European Union countries and Norway in 1999: institutional changes, measures and programmes, budget, taxation, existence of a national DSM programme, national budgets for DSM programmes, electricity pricing: energy/environment tax, national efficiency standards and regulation for new electrical appliances, implementation of Commission directives, efficiency requirements, labelling, fiscal and economic incentives. (J.S.)

  17. Energy efficiency, renewable energy and sustainable development

    Energy Technology Data Exchange (ETDEWEB)

    Ervin, C.A.

    1994-12-31

    The Office of Energy Efficiency and Renewable Energy (EE) is part of the U.S. Department of Energy that is specifically charged with encouraging the more efficient use of energy resources, and the use of renewable energy resources - such as solar power, wind power, biomass energy and geothermal energy. In the past several years, EE has increased its emphasis on technology deployment through partnerships with states, local governments and private companies. Partnerships move new discoveries more quickly into the marketplace, where they can create jobs, prevent pollution, save resources, and produce many other benefits. The author then emphasizes the importance of this effort in a number of different sections of the paper: energy consumption pervades everything we do; U.S. energy imports are rising to record levels; transportation energy demand is increasing; U.S. energy use is increasing; population growth increases world energy demand; total costs of energy consumption aren`t always counted; world energy markets offer incredible potential; cost of renewables is decreasing; clean energy is essential to sustainable development; sustainable energy policy; sustainable energy initiatives: utilities, buildings, and transportation.

  18. Energy efficiency, renewable energy and sustainable development

    International Nuclear Information System (INIS)

    Ervin, C.A.

    1994-01-01

    The Office of Energy Efficiency and Renewable Energy (EE) is part of the U.S. Department of Energy that is specifically charged with encouraging the more efficient use of energy resources, and the use of renewable energy resources - such as solar power, wind power, biomass energy and geothermal energy. In the past several years, EE has increased its emphasis on technology deployment through partnerships with states, local governments and private companies. Partnerships move new discoveries more quickly into the marketplace, where they can create jobs, prevent pollution, save resources, and produce many other benefits. The author then emphasizes the importance of this effort in a number of different sections of the paper: energy consumption pervades everything we do; U.S. energy imports are rising to record levels; transportation energy demand is increasing; U.S. energy use is increasing; population growth increases world energy demand; total costs of energy consumption aren't always counted; world energy markets offer incredible potential; cost of renewables is decreasing; clean energy is essential to sustainable development; sustainable energy policy; sustainable energy initiatives: utilities, buildings, and transportation

  19. Energy efficiency evaluation of hospital building office

    Science.gov (United States)

    Fitriani, Indah; Sangadji, Senot; Kristiawan, S. A.

    2017-01-01

    One of the strategy employed in building design is reducing energy consumption while maintaining the best comfort zone in building indoor climate. The first step to improve office buildings energy performance by evaluating its existing energy usage using energy consumption intensity (Intensitas Konsumsi Energi, IKE) index. Energy evaluation of office building for hospital dr. Sayidiman at Kabupaten Magetan has been carried out in the initial investigation. The office building is operated with active cooling (air conditioning, AC) and use limited daylighting which consumes 14.61 kWh/m2/month. This IKE value is attributed into a slightly inefficient category. Further investigation was carried out by modeling and simulating thermal energy load and room lighting in every building zone using of Ecotect from Autodesk. Three scenarios of building energy and lighting retrofit have been performed simulating representing energy efficiency using cross ventilation, room openings, and passive cooling. The results of the numerical simulation indicate that the third scenario by employing additional windows, reflector media and skylight exhibit the best result and in accordance with SNI 03-6575-2001 lighting standard. Total thermal load of the existing building which includes fabric gains, indirect solar gains, direct solar gains, ventilation fans, internal gains, inter-zonal gains and cooling load were 162,145.40 kWh. Based on the three scenarios, the thermal load value (kWh) obtained was lowest achieved scenario 2 with the thermal value of 117,539.08 kWh.The final results are interpreted from the total energy emissions evaluated using the Ecotect software, the heating and cooling demand value and specific design of the windows are important factors to determine the energy efficiency of the buildings.

  20. Energy efficiency evaluation of hospital building office

    International Nuclear Information System (INIS)

    Fitriani, Indah; Sangadji, Senot; Kristiawan, S.A.

    2017-01-01

    One of the strategy employed in building design is reducing energy consumption while maintaining the best comfort zone in building indoor climate. The first step to improve office buildings energy performance by evaluating its existing energy usage using energy consumption intensity (Intensitas Konsumsi Energi, IKE) index. Energy evaluation of office building for hospital dr. Sayidiman at Kabupaten Magetan has been carried out in the initial investigation. The office building is operated with active cooling (air conditioning, AC) and use limited daylighting which consumes 14.61 kWh/m2/month. This IKE value is attributed into a slightly inefficient category. Further investigation was carried out by modeling and simulating thermal energy load and room lighting in every building zone using of Ecotect from Autodesk. Three scenarios of building energy and lighting retrofit have been performed simulating representing energy efficiency using cross ventilation, room openings, and passive cooling. The results of the numerical simulation indicate that the third scenario by employing additional windows, reflector media and skylight exhibit the best result and in accordance with SNI 03-6575-2001 lighting standard. Total thermal load of the existing building which includes fabric gains, indirect solar gains, direct solar gains, ventilation fans, internal gains, inter-zonal gains and cooling load were 162,145.40 kWh. Based on the three scenarios, the thermal load value (kWh) obtained was lowest achieved scenario 2 with the thermal value of 117,539.08 kWh.The final results are interpreted from the total energy emissions evaluated using the Ecotect software, the heating and cooling demand value and specific design of the windows are important factors to determine the energy efficiency of the buildings. (paper)

  1. Energy-efficient and cost-effective use of district heating bypass for improving the thermal comfort in bathrooms in low-energy buildings

    DEFF Research Database (Denmark)

    Dalla Rosa, Alessandro; Brand, Marek; Svendsen, Svend

    2012-01-01

    , in the example considered 10-35% lower than in the traditional “intermittent bypass” case; secondly, it can be used to increase the thermal comfort outside the heating-season in bathrooms through floor heating, without causing overheating. It is important that the building design foresees the use of shading......, the utilization of the bypass in bathroom floor heating is a cost-effective solution, both for the DH utilities (reduced heat loss from the DH network and higher revenues), the end-users (improved thermal comfort) and the society (reduction of greenhouse gas emissions)....... floor heating to increase the users’ comfort; its techno-economic analysis, including the modelling of the in-house space heating system; the effect of the bypass to the DH network. Some conclusions were derived. First, the “continuous bypass” guarantees low heat losses in the service pipe...

  2. Effective education for energy efficiency

    International Nuclear Information System (INIS)

    Zografakis, Nikolaos; Menegaki, Angeliki N.; Tsagarakis, Konstantinos P.

    2008-01-01

    A lot of today's world vices can be eliminated if certain targeted modules and adapted curricula are introduced in the schooling system. One of these vices is energy squandering with all its negative consequences for the planet (e.g. depletion of finite energy sources and the subsequent climate change). This paper describes the results of an energy-thrift information and education project taking place in different levels of education in Crete-Greece, which records 321 students' and their parents' routine energy-related behavior and proves that this behavior changes to a more energy efficient one, after the dissemination of relevant information and the participation into the energy education projects. Namely, response percentages indicating the energy-efficient behavior increased after project participation while the ones indicating an energy-squandering behavior decreased. The Wilcoxon signed rank test was statistically significant in all energy behavior questions related to students and to most questions related to parents

  3. Energy sustainability: consumption, efficiency, and ...

    Science.gov (United States)

    One of the critical challenges in achieving sustainability is finding a way to meet the energy consumption needs of a growing population in the face of increasing economic prosperity and finite resources. According to ecological footprint computations, the global resource consumption began exceeding planetary supply in 1977 and by 2030, global energy demand, population, and gross domestic product are projected to greatly increase over 1977 levels. With the aim of finding sustainable energy solutions, we present a simple yet rigorous procedure for assessing and counterbalancing the relationship between energy demand, environmental impact, population, GDP, and energy efficiency. Our analyses indicated that infeasible increases in energy efficiency (over 100 %) would be required by 2030 to return to 1977 environmental impact levels and annual reductions (2 and 3 %) in energy demand resulted in physical, yet impractical requirements; hence, a combination of policy and technology approaches is needed to tackle this critical challenge. This work emphasizes the difficulty in moving toward energy sustainability and helps to frame possible solutions useful for policy and management. Based on projected energy consumption, environmental impact, human population, gross domestic product (GDP), and energy efficiency, for this study, we explore the increase in energy-use efficiency and the decrease in energy use intensity required to achieve sustainable environmental impact le

  4. Energy efficiency initiatives: Indian experience

    Energy Technology Data Exchange (ETDEWEB)

    Dey, Dipankar [ICFAI Business School, Kolkata, (IBS-K) (India)

    2007-07-01

    India, with a population of over 1.10 billion is one of the fastest growing economies of the world. As domestic sources of different conventional commercial energy are drying up, dependence on foreign energy sources is increasing. There exists a huge potential for saving energy in India. After the first 'oil shock' (1973), the government of India realized the need for conservation of energy and a 'Petroleum Conservation Action Group' was formed in 1976. Since then many initiatives aiming at energy conservation and improving energy efficiency, have been undertaken (the establishment of Petroleum Conservation Research Association in 1978; the notification of Eco labelling scheme in 1991; the formation of Bureau of Energy Efficiency in 2002). But no such initiative was successful. In this paper an attempt has been made to analyze the changing importance of energy conservation/efficiency measures which have been initiated in India between 1970 and 2005.The present study tries to analyze the limitations and the reasons of failure of those initiatives. The probable reasons are: fuel pricing mechanism (including subsidies), political factors, corruption and unethical practices, influence of oil and related industry lobbies - both internal and external, the economic situation and the prolonged protection of domestic industries. Further, as India is opening its economy, the study explores the opportunities that the globally competitive market would offer to improve the overall energy efficiency of the economy. The study suggests that the Bureau of Energy Efficiency (BEE) - the newly formed nodal agency for improving energy efficiency of the economy may be made an autonomous institution where intervention from the politicians would be very low. For proper implementation of different initiatives to improve energy efficiency, BEE should involve more the civil societies (NGO) from the inception to the implementation stage of the programs. The paper also

  5. Energy Efficiency and Renewable Energy Program. Bibliography, 1993 edition

    Energy Technology Data Exchange (ETDEWEB)

    Vaughan, K.H.

    1993-06-01

    The Bibliography contains listings of publicly available reports, journal articles, and published conference papers sponsored by the DOE Office of Energy Efficiency and Renewable Energy and published between 1987 and mid-1993. The topics of Bibliography include: analysis and evaluation; building equipment research; building thermal envelope systems and materials; district heating; residential and commercial conservation program; weatherization assistance program; existing buildings research program; ceramic technology project; alternative fuels and propulsion technology; microemulsion fuels; industrial chemical heat pumps; materials for advanced industrial heat exchangers; advanced industrial materials; tribology; energy-related inventions program; electric energy systems; superconducting technology program for electric energy systems; thermal energy storage; biofuels feedstock development; biotechnology; continuous chromatography in multicomponent separations; sensors for electrolytic cells; hydropower environmental mitigation; environmental control technology; continuous fiber ceramic composite technology.

  6. China's energy efficiency target 2010

    International Nuclear Information System (INIS)

    Yang Ming

    2008-01-01

    The Chinese government has set an ambitious target: reducing China's energy intensity by 20%, or 4.36% each year between 2006 and 2010 on the 2005 level. Real data showed that China missed its target in 2006, having reduced its energy intensity only by 1.3%. The objective of this study is to evaluate the feasibility and potential of the Chinese to achieve the target. This paper presents issues of macro-economy, population migration, energy savings, and energy efficiency policy measures to achieve the target. A top-down approach was used to analyse the relationship between the Chinese economic development and energy demand cycles and to identify the potentials of energy savings in sub-sectors of the Chinese economy. A number of factors that contribute to China's energy intensity are identified in a number of energy-intensive sectors. This paper concludes that China needs to develop its economy at its potential GDP growth rate; strengthen energy efficiency auditing, monitoring and verification; change its national economy from a heavy-industry-dominated mode to a light industry or a commerce-dominated mode; phase out inefficient equipment in industrial sectors; develop mass and fast railway transportation; and promote energy-efficient technologies at the end use. This paper transfers key messages to policy makers for designing their policy to achieve China's energy efficiency target

  7. Energy planning and energy efficiency assistance

    Energy Technology Data Exchange (ETDEWEB)

    Markel, L. [Electrotek Concepts, Inc., Knoxville, TN (United States)

    1995-12-31

    Electrotek is an engineering services company specializing in energy-related programs. Clients are most utilities, large energy users, and the U.S. Electric Power Research Institute. Electrotek has directed energy projects for the U.S. Agency for International Development and the U.S. Department of Energy in Poland and other countries of Central Europe. The objective is to assist the host country organizations to identify and implement appropriate energy efficiency and pollution reduction technologies, to transfer technical and organizational knowledge, so that further implementations are market-driven, without needed continuing foreign investment. Electrotek has worked with the Silesian Power Distribution Company to design an energy efficiency program for industrial customers that has proven to be profitable for the company and for its customers. The program has both saved energy and costs, and reduced pollution. The program is expanding to include additional customers, without needing more funding from the U.S. government.

  8. Energy Efficiency Governance

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    The purpose of this report is to help EE practitioners, government officials and stakeholders to establish the most effective EE governance structures, given their specific country context. It also aims to provide readers with relevant and accessible information to support the development of comprehensive and effective governance mechanisms. The International Energy Agency (IEA) conducted a global review of many elements of EE governance,including legal frameworks, institutional frameworks, funding mechanisms, co-ordination mechanisms and accountability arrangements, such as evaluation and oversight. The research tools included a survey of over 500 EE experts in 110 countries, follow-up interviews of over 120 experts in 27 countries and extensive desk study and literature searches on good EE governance.

  9. Energy Efficient Cooking - The EffiCooker

    DEFF Research Database (Denmark)

    Schjær-Jacobsen, Jørgen

    2011-01-01

    Substantial energy savings in moist heat cooking may be achieved by employing a pan with integrated electric heating element rather than an ordinary pan on a conventional electric range. The electric pan should be thermally insulated and equipped with an "intelligent" controller and timer....... A working prototype of a saucepan, dubbed the EffiCooker, has been constructed according to these guidelines. The EffiCooker has demonstrated energy savings in the range from 28% to 81% compared to conventional equipment when performing ordinary cooking tasks. The user need not be particularly aware...... of energy conservation to realize such savings; even those who are more concerned with their culinary achievements than with energy efficiency are likely to benefit. Besides being energy efficient the EffiCooker is user friendly. Many cooking tasks, once initiated, are performed automatically without any...

  10. Aquifer Thermal Energy Storage for Seasonal Thermal Energy Balance

    Science.gov (United States)

    Rostampour, Vahab; Bloemendal, Martin; Keviczky, Tamas

    2017-04-01

    Aquifer Thermal Energy Storage (ATES) systems allow storing large quantities of thermal energy in subsurface aquifers enabling significant energy savings and greenhouse gas reductions. This is achieved by injection and extraction of water into and from saturated underground aquifers, simultaneously. An ATES system consists of two wells and operates in a seasonal mode. One well is used for the storage of cold water, the other one for the storage of heat. In warm seasons, cold water is extracted from the cold well to provide cooling to a building. The temperature of the extracted cold water increases as it passes through the building climate control systems and then gets simultaneously, injected back into the warm well. This procedure is reversed during cold seasons where the flow direction is reversed such that the warmer water is extracted from the warm well to provide heating to a building. From the perspective of building climate comfort systems, an ATES system is considered as a seasonal storage system that can be a heat source or sink, or as a storage for thermal energy. This leads to an interesting and challenging optimal control problem of the building climate comfort system that can be used to develop a seasonal-based energy management strategy. In [1] we develop a control-oriented model to predict thermal energy balance in a building climate control system integrated with ATES. Such a model however cannot cope with off-nominal but realistic situations such as when the wells are completely depleted, or the start-up phase of newly installed wells, etc., leading to direct usage of aquifer ambient temperature. Building upon our previous work in [1], we here extend the mathematical model for ATES system to handle the above mentioned more realistic situations. Using our improved models, one can more precisely predict system behavior and apply optimal control strategies to manage the building climate comfort along with energy savings and greenhouse gas reductions

  11. Energy Efficiency in Future PONs

    DEFF Research Database (Denmark)

    Reschat, Halfdan; Laustsen, Johannes Russell; Wessing, Henrik

    2012-01-01

    There is a still increasing tendency to give energy efficiency a high priority, even in already low energy demanding systems. This is also the case for Passive Optical Networks (PONs) for which many different methods for saving energy are proposed. This paper uses simulations to evaluate three...... proposed power saving solutions for PONs which use sleep mechanisms for saving power. The discovered advantages and disadvantages of these methods are then used as a basis for proposing a new solution combining different techniques in order to increase the energy efficiency further. This novel solution...

  12. Numerical conversion efficiency of thermally isolated Seebeck nanoantennas

    Directory of Open Access Journals (Sweden)

    Edgar Briones

    2016-11-01

    Full Text Available In this letter, we evaluate the conversion efficiency of thermally isolated Seebeck nanoantennas by numerical simulations and discuss their uses and scope for energy harvesting applications. This analysis includes the simple case of titanium-nickel dipoles suspended in air above the substrate by a 200 nm silicon dioxide membrane to isolate the heat dissipation. Results show that substantially thermal gradients are induced along the devices leading to a harvesting efficiency around 10-4 %, 400 % higher than the previously reported Seebeck nanoantennas. In the light of these results, different optimizing strategies should be considered in order to make the Seebeck nanoantennas useful for harvesting applications.

  13. Energy efficiency: potentials and profits

    International Nuclear Information System (INIS)

    Sigaud, J.B.

    2011-01-01

    In this work, Jean-Marie Bouchereau (ADEME) has presented a review of the energy efficiency profits in France during the last 20 years and the prospects from now to 2020. Then, Geoffrey Woodward (TOTAL) and Sebastien Huchette (AXENS) have recalled the stakes involved in the energy efficiency of the upstream and downstream sectors respectively and presented examples of advances approaches illustrated by concrete cases of applications. (O.M.)

  14. Increased energy efficiency of hobs

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-01-01

    The objective of the project is to save energy when cooking food on hobs. A great part of the total energy consumption used for cooking is consumed by hobs. The amount of energy depends on the temperature used for cooking and energy used for evaporation of liquid, focussing especially on the latter in this project. CHEC B is a method for controlling the supply of energy to the zone, so that a minimum of energy is used for reaching a set temperature of the food/liquid in the pot and maintaining this temperature. Today the efficiency of hobs is between 50 - 75%. Using CHEC B the energy efficiency is expected to be higher. (au)

  15. Energy Efficiency: Finding Leadership Opportunities

    Directory of Open Access Journals (Sweden)

    William Rosehart

    2014-01-01

    Full Text Available Between 1995 and 2011, the population of Alberta increased by roughly 40 per cent, but energy use in the province grew much faster, with a 62 per cent increase over the same period. In the industrial sector, the province’s largest energy consumer, demands grew 110 per cent. In mining and oil-and-gas extraction specifically, energy use over that period soared, growing by 355 per cent. That remarkable growth in energy consumption creates a particular challenge for Alberta Premier Alison Redford, who in 2011 ordered her ministers to develop a plan that “would make Alberta the national leader in energy efficiency and sustainability.” The province is still waiting. The incentives to become more energy efficient are not particularly strong in Alberta. The province’s terrain and size favour larger and less-efficient vehicles. Energy in the province is abundant, so there is little cause for concern over energy security. And energy is relatively affordable, particularly for a population that is more affluent than the Canadian average. There is little pressure on Albertans to radically alter their energy consumption behaviour. Yet, improved energy efficiency could position businesses in Alberta to become even more globally competitive, in addition to leading to improved air quality and public health. And for a province racing to keep up with growing energy demand, effective measures that promote conservation will prove much cheaper than adding yet more expensive infrastructure to the energy network. Many other jurisdictions have already provided examples of methods Alberta could employ to effectively promote energy conservation. First, Alberta must set hard targets for its goals to save energy, and then monitor that progress through transparent accounting, measuring and reporting. The provincial government can also nurture a culture of energy conservation, by formally and publicly recognizing leadership in efficiency improvements in industry and

  16. Thermal energy storage devices, systems, and thermal energy storage device monitoring methods

    Science.gov (United States)

    Tugurlan, Maria; Tuffner, Francis K; Chassin, David P.

    2016-09-13

    Thermal energy storage devices, systems, and thermal energy storage device monitoring methods are described. According to one aspect, a thermal energy storage device includes a reservoir configured to hold a thermal energy storage medium, a temperature control system configured to adjust a temperature of the thermal energy storage medium, and a state observation system configured to provide information regarding an energy state of the thermal energy storage device at a plurality of different moments in time.

  17. Cleanroom Energy Efficiency Workshop Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Tschudi, Bill

    1999-03-15

    On March 15, 1999, Lawrence Berkeley National Laboratory hosted a workshop focused on energy efficiency in Cleanroom facilities. The workshop was held as part of a multiyear effort sponsored by the California Institute for Energy Efficiency, and the California Energy Commission. It is part of a project that concentrates on improving energy efficiency in Laboratory type facilities including cleanrooms. The project targets the broad market of laboratory and cleanroom facilities, and thus cross-cuts many different industries and institutions. This workshop was intended to raise awareness by sharing case study success stories, providing a forum for industry networking on energy issues, contributing LBNL expertise in research to date, determining barriers to implementation and possible solutions, and soliciting input for further research.

  18. Energy - efficient buildings in pakistan

    International Nuclear Information System (INIS)

    Sohail, M.; Qureshi, M.U.D.

    2011-01-01

    Pakistan is one of the countries with the highest energy consumption for domestic use. Annual energy consumption by the domestic sector is 45.9 % of the total, while the industrial sector, consumes about 27.5%. About half of the total energy consumed is used in buildings and/or heating, ventilation and air-conditioning (HVAC) and lighting appliances. The energy consumed for the same purposes in China and UK is 25 to 30 % and 40 %, respectively, even in extreme weather conditions. Energy deficiency in Pakistan is approximately 5,000 MWe, which results in worst load-shedding in summers and, lately, even in winters. Building new energy sources like dams, coal power plants and renewable energy power projects are some possible solutions, but these are time taking and need at least 2 to 6 years to complete, depending upon the nature of the project. Fast development of energy-efficient buildings is, therefore, necessary to deal with exacerbating energy-crisis and related environmental impact in Pakistan. Innovations in the prevailing building-design will help the country in reducing the energy burden. These innovations may include improved architectural designs, energy-efficient building materials, electrical appliances and implementation of building energy-efficiency codes. In 1987, the National Energy Conservation Centre (ENERCON), was established under Ministry of Environment, Government of Pakistan, with the aim to build awareness among the masses for energy conservation, and to make policies regarding energy-conservation structures in the country. But no policy regarding building energy codes has been introduced by ENERCON till now. In collaboration with Pakistan Engineering Council (PEC), ENERCON has recently finalized the Building Energy Code of Pakistan Energy Provisions 2011 for which statutory notification is under process for necessary amendment in the building by-laws. The implementation of this Energy Code will result in 25 to 30 % of energy savings in the

  19. Energy efficiency opportunities in Hotels

    Directory of Open Access Journals (Sweden)

    Dina Said

    2017-03-01

    Full Text Available According to the statistics in Egypt (2013, the number of hotels is 1193, about 407 of them have contracted power greater than 500 kW.Air conditioning, lighting, water heating and refrigeration represent the main activities demanding electrical energy in hotel business.The energy consumption per night spend changes a lot, depending on various factors; facilities provided, category of hotel, occupancy , geographical situation, weather conditions, nationality of clients, design and control of the installations.Energy benchmarking is an internal management tool designed to provide ongoing, reliable and verifiable tracking on the hotels performance. The most useful performance indicator (or Energy Efficiency Benchmarking of hotels are: Lighting Power Density (LPD in W (for lighting/m2, and energy intensity (kWh/m2/ y.There are multiple benefits for improving energy in hotel business; reduces the hotel's operating cost, reduces climate change risks and promotes green tourism.Energy efficiency opportunities are low-cost measures and cost- effective investments.   There are many energy saving opportunities for lighting in hotel's guest rooms as well as the more obvious savings in lobbies and exterior lighting areas. Behavior campaigns can yield substantial energy savings, both through the guests and housekeeper behavior. Encouraging housekeepers to use natural light during room cleaning is a simple first step to implement energy saving program.This paper presents the energy efficiency guidelines and energy benchmarking for hotels. Also a case study showing how the energy efficiency program implemented is presented. 

  20. Energy efficiency in the foreground

    International Nuclear Information System (INIS)

    Baettig, I.

    2006-01-01

    In this interview with Eberhard Jochem, professor at the Centre for Energy Policy and Economics at the Federal Institute of Science and Technology (ETH) in Zurich, Switzerland, several energy-relevant topics are discussed. These include high oil prices, possible power shortages and binding commitments in the climate-protection area. The question is asked, how, in consideration of such general conditions, energy use and energy supply should develop in Switzerland. Options for increasing efficiency or the tapping of new energy sources is discussed, as is Switzerland's increasing energy consumption. The '2000 Watt' concept being worked on at the ETH and the activities needed for its realisation are discussed. The effects of this concept on economical and business development are discussed. The potential of renewable forms of energy and the possibility of building combined gas and steam power stations are looked at. Ways of promoting renewable energy and questions concerning the extent of the state intervention in the energy business are considered

  1. Energy production and reactor efficiency

    International Nuclear Information System (INIS)

    Anon.

    1975-01-01

    Doubts have been raised in relation to the economic and energetic efficiency of nuclear reactors. Some economists are questioning whether, when all the capital and material inputs to fission technology are considered, nuclear reactors yield sufficiently large amounts of energy to show a nett gain of energy. (author)

  2. Aquifer thermal energy storage. International symposium: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-05-01

    Aquifers have been used to store large quantities of thermal energy to supply process cooling, space cooling, space heating, and ventilation air preheating, and can be used with or without heat pumps. Aquifers are used as energy sinks and sources when supply and demand for energy do not coincide. Aquifer thermal energy storage may be used on a short-term or long-term basis; as the sole source of energy or as a partial storage; at a temperature useful for direct application or needing upgrade. The sources of energy used for aquifer storage are ambient air, usually cold winter air; waste or by-product energy; and renewable energy such as solar. The present technical, financial and environmental status of ATES is promising. Numerous projects are operating and under development in several countries. These projects are listed and results from Canada and elsewhere are used to illustrate the present status of ATES. Technical obstacles have been addressed and have largely been overcome. Cold storage in aquifers can be seen as a standard design option in the near future as it presently is in some countries. The cost-effectiveness of aquifer thermal energy storage is based on the capital cost avoidance of conventional chilling equipment and energy savings. ATES is one of many developments in energy efficient building technology and its success depends on relating it to important building market and environmental trends. This paper attempts to provide guidance for the future implementation of ATES. Individual projects have been processed separately for entry onto the Department of Energy databases.

  3. Mobilising Investment in Energy Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-07-01

    Taxes, loans and grants, trading schemes and white certificates, public procurement and investment in R&D or infrastructure: known collectively as 'economic instruments', these tools can be powerful means of mobilising the finances needed to achieve policy goals by implementing energy efficiency measures. The role of economic instruments is to kick-start the private financial markets and to motivate private investors to fund EE measures. They should reinforce and promote energy performance regulations. This IEA analysis addresses the fact that, to date, relatively little effort has been directed toward evaluating how well economic instruments work. Using the buildings sector to illustrate how such measures can support energy efficiency, this paper can help policy makers better select and design economic instruments appropriate to their policy objectives and national contexts. This report’s three main aims are to: 1) Examine how economic instruments are currently used in energy efficiency policy; 2) Consider how economic instruments can be more effective and efficient in supporting low-energy buildings; and 3) Assess how economic instruments should be funded, where public outlay is needed. Detailed case studies in this report assess examples of economic instruments for energy efficiency in the buildings sector in Canada (grants), France (tax relief and loans), Germany (loans and grants), Ireland (grants) and Italy (white certificates and tax relief).

  4. Thermal energy storage for smart grid applications

    Science.gov (United States)

    Al-Hallaj, Said; Khateeb, Siddique; Aljehani, Ahmed; Pintar, Mike

    2018-01-01

    Energy consumption for commercial building cooling accounts for 15% of all commercial building's electricity usage [1]. Electric utility companies charge their customers time of use consumption charges (/kWh) and additionally demand usage charges (/kW) to limit peak energy consumption and offset their high operating costs. Thus, there is an economic incentive to reduce both the electricity consumption charges and demand charges by developing new energy efficient technologies. Thermal energy storage (TES) systems using a phase change material (PCM) is one such technology that can reduce demand charges and shift the demand from on-peak to off-peak rates. Ice and chilled water have been used in thermal storage systems for many decades, but they have certain limitations, which include a phase change temperature of 0 degrees Celsius and relatively low thermal conductivity in comparison to other materials, which limit their applications as a storage medium. To overcome these limitations, a novel phase change composite (PCC) TES material was developed that has much higher thermal conductivity that significantly improves the charge / discharge rate and a customizable phase change temperature to allow for better integration with HVAC systems. Compared to ice storage, the PCC TES system is capable of very high heat transfer rate and has lower system and operational costs. Economic analysis was performed to compare the PCC TES system with ice system and favorable economics was proven. A 4.5 kWh PCC TES prototype system was also designed for testing and validation purpose.

  5. Energy efficiency and energy management: an abundance

    International Nuclear Information System (INIS)

    Coullet-Demaiziere, Corinne; Barthet, Marie-Claire; Tourneur, Jean-Claude; Mirguet, Olivier

    2015-01-01

    As France has just published a decree on the energy audit for large companies, and has thus been among the first countries to comply with an article of the European directive on energy efficiency, a set of articles discusses various aspects of these issues of energy efficiency and energy management. A first one presents this mandatory energy audit as a tool for a better energy efficiency, and illustrates the relationship between this commitment and the ISO 50001 standard for French large companies. A second article outlines the tools and standards of application of this energy audit in different legal texts. A third one comments the introduction of four new European arrangements on the labelling of products (indication of energy performance by retailers, objective of reduction of energy consumption, information displayed on site and on-line for various household appliances, current legislation). The next article comments the new German legislation on renewable energies which implements environmental requirements higher than European objectives, and tries to boost the carbon market. The presence of the ISO 50001 certification in the German law is also briefly addressed. Then, an article proposes an overview of a bill project, opinions of experts, and way to go for the new arrangement for energy saving certificates (CEE, certificat d'economie d'energie) launched by the French ministry of Ecology, and which aims at a 700 TWh saving. The content of each article of the bill project is presented and explained, and the relationship between certificate application and some standards is highlighted. The last article comments the decision of the European Court of Justice on the compatibility of Flemish Green Certificates with the European law

  6. Green corridor : energy efficiency initiatives

    Energy Technology Data Exchange (ETDEWEB)

    Bartlett, M.; Strickland, R.; Harding, N. [Windsor Univ., ON (Canada)

    2005-07-01

    This presentation discussed environmental sustainability using alternative energy technologies. It discussed Ecohouse, which is a house designed using conventional and inventive products and techniques to represent an eco-efficient model for living, a more sustainable house, demonstrating sustainable technologies in action and setting a new standard for resource efficiency in Windsor. The presentation provided a building analysis and discussed the following: geothermal heating; distributive power; green roof; net metering; grey water plumbing; solar water heating; passive lighting; energy efficient lighting and geothermal heating and cooling. It also discussed opportunities for innovation, namely: greenhouse; composting toilets; alternative insulation; net metering; solar arrays; hydroponics; and expansion of the house. Also discussed were a nature bridge, an underwater electric kite, and a vertically aerodynamic turbine. The benefits of renewable energy, small hydro power potential, and instream energy generation technology were presented. 9 refs., figs.

  7. Energy Efficiency Policy in Slovenia

    International Nuclear Information System (INIS)

    Beravs, F.

    1998-01-01

    When Slovenia gained its independence in 1991, its energy sector was characterised by largely centralised state planning and artificially low prices maintained by widespread subsidies. Supply side considerations tended to dominate the energy policy and sectoral planning. As a result the final energy intensity in Slovenia was (still albeit declining) considerably higher than the EU average. In order to support economic growth and transition to a modern market economy, integrated and competitive in the European and world market structures, the National Assembly of the Republic of Slovenia adopted a resolution on the Strategy of Energy Use and Supply of Slovenia in early 1996. In the field of energy use, the long-term strategic orientation is to increase energy efficiency in all sectors of energy consumption. The main objective can be summarised as to secure the provision of reliable and environmentally friendly energy services at least costs. In quantitative terms the Strategy attaches a high priority to energy efficiency and environmental protection and sets the target of improving the overall energy efficiency by 2% p.a. over the next 10 to 15 years. To achieve the target mentioned above the sectoral approach and a number of policy instruments have been foreseen. Besides market based energy prices which will, according to the European Energy Charter, gradually incorporate the cost of environment and social impacts, the following policy instruments will be intensified and budget-supported: education and awareness building, energy consultation, regulations and agreements, financial incentives, innovation and technology development. The ambitious energy conservation objectives represent a great challenge to the whole society. (author)

  8. Energy Efficiency Indicators Methodology Booklet

    Energy Technology Data Exchange (ETDEWEB)

    Sathaye, Jayant; Price, Lynn; McNeil, Michael; de la rue du Can, Stephane

    2010-05-01

    This Methodology Booklet provides a comprehensive review and methodology guiding principles for constructing energy efficiency indicators, with illustrative examples of application to individual countries. It reviews work done by international agencies and national government in constructing meaningful energy efficiency indicators that help policy makers to assess changes in energy efficiency over time. Building on past OECD experience and best practices, and the knowledge of these countries' institutions, relevant sources of information to construct an energy indicator database are identified. A framework based on levels of hierarchy of indicators -- spanning from aggregate, macro level to disaggregated end-use level metrics -- is presented to help shape the understanding of assessing energy efficiency. In each sector of activity: industry, commercial, residential, agriculture and transport, indicators are presented and recommendations to distinguish the different factors affecting energy use are highlighted. The methodology booklet addresses specifically issues that are relevant to developing indicators where activity is a major factor driving energy demand. A companion spreadsheet tool is available upon request.

  9. Local Thermal Insulating Materials For Thermal Energy Storage ...

    African Journals Online (AJOL)

    Thermal insulation is one of the most important components of a thermal energy storage system. In this paper the thermal properties of selected potential local materials which can be used for high temperature insulation are presented. Thermal properties of seven different samples were measured. Samples consisted of: ...

  10. Microwavable thermal energy storage material

    Science.gov (United States)

    Salyer, I.O.

    1998-09-08

    A microwavable thermal energy storage material is provided which includes a mixture of a phase change material and silica, and a carbon black additive in the form of a conformable dry powder of phase change material/silica/carbon black, or solid pellets, films, fibers, moldings or strands of phase change material/high density polyethylene/ethylene vinyl acetate/silica/carbon black which allows the phase change material to be rapidly heated in a microwave oven. The carbon black additive, which is preferably an electrically conductive carbon black, may be added in low concentrations of from 0.5 to 15% by weight, and may be used to tailor the heating times of the phase change material as desired. The microwavable thermal energy storage material can be used in food serving applications such as tableware items or pizza warmers, and in medical wraps and garments. 3 figs.

  11. CEE Energy Efficiency Report - Slovakia

    International Nuclear Information System (INIS)

    Hecl, V.

    2005-01-01

    A review of future trends of energy consumption shows that, in the absence of an active energy policy which promotes energy efficiency, energy consumption will increase as a whole by approximately 6.8% by 2012 continuing to raise after this period.. This result hides large differences between the different sources of energy (mainly heat, fuels and electricity) and between the different sectors - transport, industry, buildings etc. It is therefore clear that a strong energy policy is needed to counterbalance the expected increase in energy consumption in all sectors, with emphasis on measures in the building sector (both residential and tertiary) and in the transport sector. Furthermore improvements in the district heating sector are also essential to prevent further disconnection from district heating and a shift to other means of heating. A review of the main barriers to energy efficiency leads to the conclusion that while significant changes are needed in the regulatory framework, the lack of access to finance and the general lack of awareness about existing technologies and best practice represent the greatest barriers. In order to evaluate the success of energy. In a few studies available from past 2-3 years the calculation of low and high targets for energy policy was elaborated. The low targets would represent about 11% - 12% reduction in overall energy consumption. The high targets would represent a 13% - 15% reduction in overall energy consumption. Policy instruments have been identified which can turn energy efficiency into one of the driving forces of the overall economic and development strategy of the country. Some of these instruments deal with general issues such as general policy issues, regulatory and legal aspects, the institutional framework and fiscal, taxation and pricing policy. They are designed to improve the present conditions and would use only a limited part of the available public budget. The state budget dedicated to energy issues will

  12. Effects of thermal efficiency in DCMD and the preparation of membranes with low thermal conductivity

    Energy Technology Data Exchange (ETDEWEB)

    Li, Zhehao, E-mail: ccgri_lzh@163.com [Changchun Gold Research Institute, 130012 (China); Peng, Yuelian, E-mail: pyl@live.com.au [Department of Chemistry and Chemical Engineering, College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124 (China); Dong, Yajun; Fan, Hongwei [Department of Chemistry and Chemical Engineering, College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124 (China); Chen, Ping [The Research Institute of Environmental Protection, North China Pharmaceutical Group Corporation, 050015 (China); Qiu, Lin [Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100190 (China); Jiang, Qi [National Major Science and Technology Program Management Office for Water Pollution Control and Treatment, MEP, 100029 (China)

    2014-10-30

    Highlights: • The effects on vapor flux and thermal efficiency were simulated. • The conditions favoring vapor flux also favored thermal efficiency. • Four microporous polymer membranes were compared. • The SiO{sub 2} aerogel coating reduced the thermal conductivity of polymer membranes. • A 3ω technique was used to measure the thermal conductivity of membranes. - Abstract: The effects of the membrane characteristics and operational conditions on the vapor flux and thermal efficiency in a direct contact membrane distillation (DCMD) process were studied with a mathematical simulation. The membrane temperature, driving force of vapor transfer, membrane distillation coefficient, etc. were used to analyze the effects. The operating conditions that increased the vapor flux improved the thermal efficiency. The membrane characteristics of four microporous membranes and their performances in DCMD were compared. A polysulfone (PSf) membrane prepared via vapor-induced phase separation exhibited the lowest thermal conductivity. The PSf and polyvinylidene difluoride (PVDF) membranes were modified using SiO{sub 2} aerogel blending and coating to reduce the thermal conductivity of the membrane. The coating process was more effective than the blending process toward this end. The changes in the structure of the modified membrane were observed with a scanning electron microscope. Si was found on the modified membrane surface with an energy spectrometer. The PVDF composite and support membranes were tested during the DCMD process; the composite membrane had a higher vapor flux and a better thermal efficiency than the support. A new method based on a 3ω technique was used to measure the thermal conductivity of the membranes.

  13. Effects of thermal efficiency in DCMD and the preparation of membranes with low thermal conductivity

    International Nuclear Information System (INIS)

    Li, Zhehao; Peng, Yuelian; Dong, Yajun; Fan, Hongwei; Chen, Ping; Qiu, Lin; Jiang, Qi

    2014-01-01

    Highlights: • The effects on vapor flux and thermal efficiency were simulated. • The conditions favoring vapor flux also favored thermal efficiency. • Four microporous polymer membranes were compared. • The SiO 2 aerogel coating reduced the thermal conductivity of polymer membranes. • A 3ω technique was used to measure the thermal conductivity of membranes. - Abstract: The effects of the membrane characteristics and operational conditions on the vapor flux and thermal efficiency in a direct contact membrane distillation (DCMD) process were studied with a mathematical simulation. The membrane temperature, driving force of vapor transfer, membrane distillation coefficient, etc. were used to analyze the effects. The operating conditions that increased the vapor flux improved the thermal efficiency. The membrane characteristics of four microporous membranes and their performances in DCMD were compared. A polysulfone (PSf) membrane prepared via vapor-induced phase separation exhibited the lowest thermal conductivity. The PSf and polyvinylidene difluoride (PVDF) membranes were modified using SiO 2 aerogel blending and coating to reduce the thermal conductivity of the membrane. The coating process was more effective than the blending process toward this end. The changes in the structure of the modified membrane were observed with a scanning electron microscope. Si was found on the modified membrane surface with an energy spectrometer. The PVDF composite and support membranes were tested during the DCMD process; the composite membrane had a higher vapor flux and a better thermal efficiency than the support. A new method based on a 3ω technique was used to measure the thermal conductivity of the membranes

  14. Thermal Energy Storage with Phase Change Material

    Directory of Open Access Journals (Sweden)

    Lavinia Gabriela SOCACIU

    2012-08-01

    Full Text Available Thermal energy storage (TES systems provide several alternatives for efficient energy use and conservation. Phase change materials (PCMs for TES are materials supplying thermal regulation at particular phase change temperatures by absorbing and emitting the heat of the medium. TES in general and PCMs in particular, have been a main topic in research for the last 30 years, but although the information is quantitatively enormous, it is also spread widely in the literature, and difficult to find. PCMs absorb energy during the heating process as phase change takes place and release energy to the environment in the phase change range during a reverse cooling process. PCMs possesses the ability of latent thermal energy change their state with a certain temperature. PCMs for TES are generally solid-liquid phase change materials and therefore they need encapsulation. TES systems using PCMs as a storage medium offers advantages such as high TES capacity, small unit size and isothermal behaviour during charging and discharging when compared to the sensible TES.

  15. Improvement of energy efficiency: the use of thermography and air-tightness test in verification of thermal performance of school buildings

    Science.gov (United States)

    Kauppinen, Timo; Siikanen, Sami

    2011-05-01

    The improvement of energy efficiency is the key issue after the energy performance of buildings directive came into the force in European Union countries. The city of Kuopio participate a project, in which different tools will be used, generated and tested to improve the energy efficiency of public buildings. In this project there are 2 schools, the other consuming much more heating energy than the other same type of school. In this paper the results of the thermography in normal conditions and under 50 Pa pressure drop will be presented; as well as the results of remote controlled air tightness test of the buildings. Thermography combined with air tightness test showed clearly the reasons of specific consumption differences of heating energy - also in the other hand, the measurements showed the problems in the performance of ventilation system. Thermography, air tightness test and other supporting measurements can be used together to solve energy loss problems - if these measurements will be carried out by proper way.

  16. Energy and Water Efficiency on Campus | NREL

    Science.gov (United States)

    Energy and Water Efficiency on Campus Energy and Water Efficiency on Campus NREL ensures the resiliency of our future energy and water systems through energy efficiency strategies and technologies , renewable energy, and water efficiency on the NREL campus. FY17 Energy Intensity. The South Table Mountain

  17. Energy Efficient Hydraulic Hybrid Drives

    OpenAIRE

    Rydberg, Karl-Erik

    2009-01-01

    Energy efficiency of propulsion systems for cars, trucks and construction machineries has become one of the most important topics in today’s mobile system design, mainly because of increased fuel costs and new regulations about engine emissions, which is needed to save the environment. To meet the increased requirements on higher efficiency and better functionality, components and systems have been developed over the years. For the last ten years the development of hybrid systems can be divid...

  18. Energy Efficient Drivepower: An Overview.

    Energy Technology Data Exchange (ETDEWEB)

    Ula, Sadrul; Birnbaum, Larry E.; Jordan, Don

    1993-05-01

    This report examines energy efficiency in drivepower systems. Only systems where the prime movers are electrical motors are discussed. A systems approach is used to examine all major aspects of drivepower, including motors, controls, electrical tune-ups, mechanical efficiency, maintenance, and management. Potential annual savings to the US society of $25 to $50 billion are indicated. The report was written for readers with a semi-technical background.

  19. Highly Efficient Green-Emitting Phosphors Ba2Y5B5O17 with Low Thermal Quenching Due to Fast Energy Transfer from Ce3+ to Tb3.

    Science.gov (United States)

    Xiao, Yu; Hao, Zhendong; Zhang, Liangliang; Xiao, Wenge; Wu, Dan; Zhang, Xia; Pan, Guo-Hui; Luo, Yongshi; Zhang, Jiahua

    2017-04-17

    This paper demonstrates a highly thermally stable and efficient green-emitting Ba 2 Y 5 B 5 O 17 :Ce 3+ , Tb 3+ phosphor prepared by high-temperature solid-state reaction. The phosphor exhibits a blue emission band of Ce 3+ and green emission lines of Tb 3+ upon Ce 3+ excitation in the near-UV spectral region. The effect of Ce 3+ to Tb 3+ energy transfer on blue to green emission color tuning and on luminescence thermal stability is studied in the samples codoped with 1% Ce 3+ and various concentrations (0-40%) of Tb 3+ . The green emission of Tb 3+ upon Ce 3+ excitation at 150 °C can keep, on average, 92% of its intensity at room temperature, with the best one showing no intensity decreasing up to 210 °C for 30% Tb 3+ . Meanwhile, Ce 3+ emission intensity only keeps 42% on average at 150 °C. The high thermal stability of the green emission is attributed to suppression of Ce 3+ thermal de-excitation through fast energy transfer to Tb 3+ , which in the green-emitting excited states is highly thermally stable such that no lifetime shortening is observed with raising temperature to 210 °C. The predominant green emission is observed for Tb 3+ concentration of at least 10% due to efficient energy transfer with the transfer efficiency approaching 100% for 40% Tb 3+ . The internal and external quantum yield of the sample with Tb 3+ concentration of 20% can be as high as 76% and 55%, respectively. The green phosphor, thus, shows attractive performance for near-UV-based white-light-emitting diodes applications.

  20. The Challenge of Energy Efficiency

    International Nuclear Information System (INIS)

    Alonso Gonzalez, J. A.

    2009-01-01

    Recent Directive 2009/28/EC on the promotion of the use of renewable energies sets some binding targets for the contribution of renewable energies in 2020 to total consumption, setting the share at 20% of final energy demand, with a particularisation of 10% for the transport sector, and also a 20% reduction of greenhouse gases Together with these targets, it also sets another target relative to energy efficiency, aiming for a 20% improvement, under the terms set down by the Commission in its announcement dated 19 October 2006. This energy saving target is going to have a decisive influence on the achievement of the other two. In order to quantify the degree of difficulty of achieving the saving target and determine the policies and measures to be taken, we are going to analyze the evolution of energy efficiency (energy consumption energy units per unit of GDP - economic unit) in Spain from 1980 to date and the value of energy intensity that we should have in 2020 to achieve the targets. This will give us an idea of the magnitude of the challenge and, therefore, of the efforts we will have to make to achieve the target. (Author)

  1. Energy efficiency standards and innovation

    Science.gov (United States)

    Morrison, Geoff

    2015-01-01

    Van Buskirk et al (2014 Environ. Res. Lett. 9 114010) demonstrate that the purchase price, lifecycle cost and price of improving efficiency (i.e. the incremental price of efficiency gain) decline at an accelerated rate following the adoption of the first energy efficiency standards for five consumer products. The authors show these trends using an experience curve framework (i.e. price/cost versus cumulative production). While the paper does not draw a causal link between standards and declining prices, they provide suggestive evidence using markets in the US and Europe. Below, I discuss the potential implications of the work.

  2. State Energy Efficiency Benefits and Opportunities

    Science.gov (United States)

    Describes the benefits of energy efficiency and how to assess its potential for your state. Also, find details on energy efficiency policies, programs, and resources available for furthering energy efficiency goals.

  3. Thermal performance and heat transport in aquifer thermal energy storage

    NARCIS (Netherlands)

    Sommer, W.T.; Doornenbal, P.J.; Drijver, B.C.; Gaans, van P.F.M.; Leusbrock, I.; Grotenhuis, J.T.C.; Rijnaarts, H.H.M.

    2014-01-01

    Aquifer thermal energy storage (ATES) is used for seasonal storage of large quantities of thermal energy. Due to the increasing demand for sustainable energy, the number of ATES systems has increased rapidly, which has raised questions on the effect of ATES systems on their surroundings as well as

  4. EYES -- Energy Efficient Sensor Networks

    NARCIS (Netherlands)

    Havinga, Paul J.M.; Etalle, Sandro; Karl, Holger; Petrioli, Chiara; Zorzi, Michele; Kip, Harry; Lentsch, Thomas; Conti, M.; Giordano, S.; Gregori, E.; Olariu, S.

    The EYES project (IST-2001-34734) is a three years European research project on self-organizing and collaborative energy-efficient sensor networks. It will address the convergence of distributed information processing, wireless communications, and mobile computing. The goal of the project is to

  5. Development of the ultra high efficiency thermal power generation facility

    Energy Technology Data Exchange (ETDEWEB)

    Sano, Toshihiro

    2010-09-15

    In order to prevent global warming, attention is focused on nuclear power generation and renewable energy such as wind and solar power generation. The electric power suppliers of Japan are aiming to increase the amount of nuclear and non-fossil fuel power generation over 50% of the total power generation by 2020. But this means that the remaining half will still be of thermal power generation using fossil fuel and will still play an important role. Under such circumstances, further efficiency improvement of the thermal power generation and its aggressive implementation is ongoing in Japan.

  6. Utilities and energy efficiency Denmark report

    Energy Technology Data Exchange (ETDEWEB)

    Olesen, G.B.; Lyck, N.C.

    1996-11-01

    The report is the Danish contribution to the project `Utilities and Energy Efficiency` produced for the European Commission by IET, Nikkel straat 15, 4823 AE Breda, The Netherlands. Information is given under the headings of existing situation and desired situation. Recommendations are also given under the headings of legislation concerning the objectives of the utilities, of government programs and targets, of organizational structure, required market dependence and internal objectives of the utilities, for regulation and standardization, and of tariff structure. Flow diagrams are presented for the Danish energy system 1990, 1993. The 1993 follow up of the energy plan `Energy 2000` points out that the goals set up at that time, first and foremost the 20% reduction in CO{sub 2} emissions in 2005 compared to the 1988 level, will not be reached without changes in policy, such as an increase in the use of renewable energy, more transparent and consistent tariff systems as a greater incentive for energy conservation, regulations on thermal insulation of houses, increase in public information activities,a new subsidy scheme to stimulate improvements of energy efficiency in buildings and regulations on energy supply to large buildings. (ARW) 55 refs.

  7. Southern Energy Efficiency Center (SEEC)

    Energy Technology Data Exchange (ETDEWEB)

    Vieira, Robin; Sonne, Jeffrey; Withers, Charles; Cummings, James; Verdict, Malcolm; Roberts, Sydney

    2009-09-30

    The Southern Energy Efficiency Center (SEEC) builds collaborative partnerships with: state and local governments and their program support offices, the building delivery industry (designers, contractors, realtors and commissioning agents), product manufacturers and their supply chains, utilities and their program implementers, consumers and other stakeholders in order to forge a strong regional network of building energy efficiency allies. Through a project Steering Committee composed of the state energy offices and building industry stakeholders, the SEEC works to establish consensus-based goals, priorities and strategies at the regional, state and local levels that will materially advance the deployment of high-performance “beyond code” buildings. In its first Phase, SEEC will provide limited technical and policy support assistance, training, certification and education to a wide spectrum of the building construction, codes and standards, and the consumer marketplace.

  8. From photoluminescence to thermal emission: Thermally-enhanced PL (TEPL) for efficient PV (Conference Presentation)

    Science.gov (United States)

    Manor, Assaf; Kruger, Nimrod; Martin, Leopoldo L.; Rotschild, Carmel

    2016-09-01

    The Shockley-Queisser efficiency limit of 40% for single-junction photovoltaic (PV) cells is mainly caused by the heat dissipation accompanying the process of electro-chemical potential generation. Concepts such as solar thermo-photovoltaics (STPV) aim to harvest this heat loss by the use of a primary absorber which acts as a mediator between the sun and the PV, spectrally shaping the light impinging on the cell. However, this approach is challenging to realize due to the high operating temperatures of above 2000K required in order to generate high thermal emission fluxes. After over thirty years of STPV research, the record conversion efficiency for STPV device stands at 3.2% for 1285K operating temperature. In contrast, we recently demonstrated how thermally-enhanced photoluminescence (TEPL) is an optical heat-pump, in which photoluminescence is thermally blue-shifted upon heating while the number of emitted photons is conserved. This process generates energetic photon-rates which are comparable to thermal emission in significantly reduced temperatures, opening the way for a TEPL based energy converter. In such a device, a photoluminescent low bandgap absorber replaces the STPV thermal absorber. The thermalization heat induces a temperature rise and a blue-shifted emission, which is efficiently harvested by a higher bandgap PV. We show that such an approach can yield ideal efficiencies of 70% at 1140K, and realistic efficiencies of almost 50% at moderate concentration levels. As an experimental proof-of-concept, we demonstrate 1.4% efficient TEPL energy conversion of an Nd3+ system coupled to a GaAs cell, at 600K.

  9. 77 FR 50489 - Office of Energy Efficiency and Renewable Energy

    Science.gov (United States)

    2012-08-21

    ... DEPARTMENT OF ENERGY Office of Energy Efficiency and Renewable Energy Wind and Water Power Program AGENCY: Office of Energy Efficiency and Renewable Energy, Department of Energy. ACTION: Notice of public... FURTHER INFORMATION CONTACT: Mr. Hoyt Battey, Office of Energy Efficiency and Renewable Energy, U.S...

  10. Ocean thermal-energy conversion

    Energy Technology Data Exchange (ETDEWEB)

    Ford, G; Niblett, C; Walker, L

    1983-03-01

    Ocean thermal-energy conversion (OTEC) is a novel 'alternative' energy technology that has created much interest in a number of countries; namely, the USA, Japan, France, Sweden, Holland, India and most recently, the UK. In particular, the first three of these have had programmes to develop the required technology. However, most interest has been centred in the USA, where the current hiatus in Federal funding provides a timely opportunity to assess progress. This paper offers a survey of the prevailing position there; outlining the outstanding technical and associated problems, and likely future developments. Non-USA programmes are only mentioned to contrast them with the American position. At present, it does not appear that OTEC plants will be commercially viable on a widespread basis even in the tropics. This is particularly true of the larger plants (400 MWe, MWe = megawatts of electrical energy, the final output of a power station) towards which the American programme is ultimately geared. There does seem to be a strong possibility that small OTEC plants, around 40 MWe or less, can be commercial in certain circumstances. This would be possible when one or, preferably, more of the following conditions are met: (i) where a land-based rather than 'at sea' plant is possible, (ii) where alternative energy supplies are at a premium, i.e. islands or regions without indigenous energy supplies, and (iii) where conditions are such that an OTEC plant could operate in conjunction with either or both an aquaculture or desalination plant.

  11. Energy Performance and Thermal Comfort of a High Efficiency House: RhOME for denCity, Winner of Solar Decathlon Europe 2014

    Directory of Open Access Journals (Sweden)

    Gabriele Battista

    2015-07-01

    Full Text Available The increase of people living in large cities and the expansion of new urban areas are keys to defining new sustainable models. It is estimated that about 70% of the EU population lives in urban areas, and it is expected to reach 80% by 2030. Consequently, it is important to find a new concept of buildings that can reduce the total energy consumption. The Solar Decathlon is an international university competition, born in 2002, created by the U.S. State Energy Department (DOE. Students are challenged to design and operate a full-scale, innovative and sustainable house able to exploit solar radiation as its sole energy source. The objective of the competition is to promote research and education in sustainable architecture and solar energy fields. This paper presents an overview on the contribution of LIFT (Interdisciplinary Laboratory of Technical Physics of Roma Tre University to the winning project of the Solar Decathlon Europe 2014 competition: The RhOME for denCity. This project consists of a building properly designed to produce a solar-powered house that is cost-effective, energy-efficient, and attractive.

  12. Energy-Efficient Neuromorphic Classifiers.

    Science.gov (United States)

    Martí, Daniel; Rigotti, Mattia; Seok, Mingoo; Fusi, Stefano

    2016-10-01

    Neuromorphic engineering combines the architectural and computational principles of systems neuroscience with semiconductor electronics, with the aim of building efficient and compact devices that mimic the synaptic and neural machinery of the brain. The energy consumptions promised by neuromorphic engineering are extremely low, comparable to those of the nervous system. Until now, however, the neuromorphic approach has been restricted to relatively simple circuits and specialized functions, thereby obfuscating a direct comparison of their energy consumption to that used by conventional von Neumann digital machines solving real-world tasks. Here we show that a recent technology developed by IBM can be leveraged to realize neuromorphic circuits that operate as classifiers of complex real-world stimuli. Specifically, we provide a set of general prescriptions to enable the practical implementation of neural architectures that compete with state-of-the-art classifiers. We also show that the energy consumption of these architectures, realized on the IBM chip, is typically two or more orders of magnitude lower than that of conventional digital machines implementing classifiers with comparable performance. Moreover, the spike-based dynamics display a trade-off between integration time and accuracy, which naturally translates into algorithms that can be flexibly deployed for either fast and approximate classifications, or more accurate classifications at the mere expense of longer running times and higher energy costs. This work finally proves that the neuromorphic approach can be efficiently used in real-world applications and has significant advantages over conventional digital devices when energy consumption is considered.

  13. ICT applications enhancing energy efficiency

    Directory of Open Access Journals (Sweden)

    A. G. Matani

    2016-06-01

    Full Text Available Computers, laptops and mobile devices – information technology (IT accounts for 2% of human greenhouse gas emissions worldwide, as evidenced in a study by Global Action Plan, a UK based environmental organization. This figure can be reduced if the green segment, or Green IT, continues to grow. Energy can also be saved through cloud computing, namely the principle of outsourcing the programs and functions of one’s own computer to service providers over the internet. This also means sharing storage capacity with others. This paper highlights the impact of information technology applications towards enhancing energy efficiency of the systems.

  14. 78 FR 20896 - Renewable Energy and Energy Efficiency Advisory Committee

    Science.gov (United States)

    2013-04-08

    ... DEPARTMENT OF COMMERCE International Trade Administration Renewable Energy and Energy Efficiency... of an Open Meeting. SUMMARY: The Renewable Energy and Energy Efficiency Advisory Committee (RE&EEAC... industry-specific teams--renewable energy, energy efficiency, energy storage and transmission, and biofuels...

  15. 75 FR 70214 - Renewable Energy and Energy Efficiency Advisory Committee

    Science.gov (United States)

    2010-11-17

    ... DEPARTMENT OF COMMERCE International Trade Administration Renewable Energy and Energy Efficiency... of an open meeting. SUMMARY: The Renewable Energy and Energy Efficiency Advisory Committee (RE&EEAC... submitted to the Renewable Energy and Energy Efficiency Advisory Committee, Office of Energy and...

  16. Frontiers in the economics of energy efficiency

    International Nuclear Information System (INIS)

    Miguel, Carlos de; Labandeira, Xavier; Löschel, Andreas

    2015-01-01

    Energy efficiency has become an essential instrument to obtain effective greenhouse gas mitigation and reduced energy dependence. This introductory article contextualizes the contributions of the supplemental issue by showing the new setting for energy efficiency economics and policy; discussing the role of price instruments to promote energy savings; presenting new approaches for energy efficiency policies; and placing energy efficiency within a wider energy and environmental framework.

  17. Energy-efficient neuromorphic classifiers

    OpenAIRE

    Martí, Daniel; Rigotti, Mattia; Seok, Mingoo; Fusi, Stefano

    2015-01-01

    Neuromorphic engineering combines the architectural and computational principles of systems neuroscience with semiconductor electronics, with the aim of building efficient and compact devices that mimic the synaptic and neural machinery of the brain. Neuromorphic engineering promises extremely low energy consumptions, comparable to those of the nervous system. However, until now the neuromorphic approach has been restricted to relatively simple circuits and specialized functions, rendering el...

  18. Effective use of thermal energy at both hot and cold side of thermoelectric module for developing efficient thermoelectric water distillation system

    International Nuclear Information System (INIS)

    Al-Madhhachi, Hayder; Min, Gao

    2017-01-01

    Highlights: • New distillation process using thermoelectric to assist evaporation/condensation. • Novel thermoelectric distillation system with reduced specific energy consumption. • Freshwater production by thermoelectrically assisted evaporation and condensation. - Abstract: An efficient thermoelectric distillation system has been designed and constructed for production of drinkable water. The unique design of this system is to use the heat from hot side of the thermoelectric module for water evaporation and the cold side for vapour condensation simultaneously. This novel design significantly reduces energy consumption and improves the system performance. The results of experiments show that the average water production is 28.5 mL/h with a specific energy consumption of 0.00114 kW h/mL in an evaporation chamber filled with 10 × 10 × 30 mm"3 of water. This is significantly lower than the energy consumption required by other existing thermoelectric distillation systems. The results also show that a maximum temperature difference between the hot and cold side of the thermoelectric module is 42.3 °C, which led to temperature increases of 26.4 °C and 8.4 °C in water and vapour, respectively.

  19. Energy efficiency information systems. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    It is well known that different cultures and countries are receptive in different ways to information transfer. Modern information technology, including computers, videos, and telecommunications, can provide a very useful tool for the dissemination of information. At the same time, however, the use of new media involves many new and varied challenges. It is important therefore that the new dissemination methods are developed and utilised in the most effective way depending on the subjects distinctive character, needs and traditions. This workshop was designed to gather experts from all the CADDET member countries, to share knowledge, experiences and ideas about the use of new methods of information exchange and training in the field of energy efficiency. The workshop was divided into four plenary sessions: dissemination of information on energy efficient technologies; training technologies and effective learning; computer-based training tools on energy efficiency; databases and network resources. Two discussion groups followed the plenary sessions, to concentrate on: different aspects of information exchange; and different aspects of state-of-the-art training tools. The workshop was attended by 44 participants from 17 countries, and included 14 speakers

  20. Building energy efficiency in different climates

    International Nuclear Information System (INIS)

    Lam, Joseph C.; Wan, Kevin K.W.; Tsang, C.L.; Yang Liu

    2008-01-01

    Energy simulation was conducted for office buildings in the five major climate zones - severe cold, cold, hot summer and cold winter, mild, and hot summer and warm winter - in China using DOE-2.1E. The primary aim was to investigate the thermal and energy performance of office buildings with centralised heating, ventilation and air conditioning plants in the major climatic zones in China. The computed results were analysed in three aspects - heating load, cooling load and the corresponding building energy consumption. The building peak monthly heating load varied from 142 MW h (1033 MW h cooling) in Hong Kong to 447 MW h (832 MW h cooling) in Harbin. It was also found that passive solar designs could have large energy savings potential in the severe cold and cold climates. In Harbin, the window solar component helped lower the annual building heating load by 650 MW h. Internal loads (lighting and office equipment) and part load operations of fans and pumps also played a significant role in the overall building energy efficiency. This paper presents the work, its findings and energy efficiency implications

  1. New energy technologies 4. Energy management and energy efficiency

    International Nuclear Information System (INIS)

    Sabonnadiere, J.C.; Caire, R.; Raison, B.; Quenard, D.; Verneau, G.; Zissis, G.

    2007-01-01

    This forth tome of the new energy technologies handbook is devoted to energy management and to the improvement of energy efficiency. The energy management by decentralized generation insertion and network-driven load control, analyzes the insertion and management means of small power generation in distribution networks and the means for load management by the network with the aim of saving energy and limiting peak loads. The second part, devoted to energy efficiency presents in a detailed way the technologies allowing an optimal management of energy in buildings and leading to the implementation of positive energy buildings. A special chapter treats of energy saving using new lighting technologies in the private and public sectors. Content: 1 - decentralized power generation - impacts and solutions: threat or opportunity; deregulation; emerging generation means; impact of decentralized generation on power networks; elements of solution; 2 - mastery of energy demand - loads control by the network: stakes of loads control; choice of loads to be controlled; communication needs; measurements and controls for loads control; model and algorithm needs for loads control. A better energy efficiency: 3 - towards positive energy buildings: key data for Europe; how to convert fossil energy consuming buildings into low-energy consuming and even energy generating buildings; the Minergie brand; the PassivHaus or 'passive house' label; the zero-energy house/zero-energy home (ZEH); the zero-energy building (ZEB); the positive energy house; comparison between the three Minergie/PassivHaus/ZEH types of houses; beyond the positive energy building; 4 - light sources and lighting systems - from technology to energy saving: lighting yesterday and today; light sources and energy conversion; energy saving in the domain of lighting: study of some type-cases; what future for light sources. (J.S.)

  2. Solar energy thermally powered electrical generating system

    Science.gov (United States)

    Owens, William R. (Inventor)

    1989-01-01

    A thermally powered electrical generating system for use in a space vehicle is disclosed. The rate of storage in a thermal energy storage medium is controlled by varying the rate of generation and dissipation of electrical energy in a thermally powered electrical generating system which is powered from heat stored in the thermal energy storage medium without exceeding a maximum quantity of heat. A control system (10) varies the rate at which electrical energy is generated by the electrical generating system and the rate at which electrical energy is consumed by a variable parasitic electrical load to cause storage of an amount of thermal energy in the thermal energy storage system at the end of a period of insolation which is sufficient to satisfy the scheduled demand for electrical power to be generated during the next period of eclipse. The control system is based upon Kalman filter theory.

  3. Application of the thermal efficiency analysis software 'EgWin' at existing power plants

    International Nuclear Information System (INIS)

    Koda, E.; Takahashi, T.; Nakao, Y.

    2008-01-01

    'EgWin' is the general purpose software to analyze a thermal efficiency of power system developed in CRIEPI. This software has been used to analyze the existing power generation unit of 30 or more, and the effectiveness has been confirmed. In thermal power plants, it was used for the clarification of the thermal efficiency decrease factor and the quantitative estimation of the influence that each factor gave to the thermal efficiency of the plant. Also it was used for the quantitative estimation of the effect by the operating condition change and the facility remodeling in thermal power, atomic energy, and geothermal power plants. (author)

  4. 77 FR 6783 - Renewable Energy and Energy Efficiency Advisory Committee

    Science.gov (United States)

    2012-02-09

    ... DEPARTMENT OF COMMERCE International Trade Administration Renewable Energy and Energy Efficiency... of an open meeting. SUMMARY: The Renewable Energy and Energy Efficiency Advisory Committee (RE&EEAC... competitiveness of U.S. renewable [[Page 6784

  5. Energy efficiency public service advertising campaign

    Energy Technology Data Exchange (ETDEWEB)

    Gibson-Grant, Amanda [Advertising Council, New York, NY (United States)

    2015-06-12

    The Advertising Council (“the Ad Council”) and The United States Department of Energy (DOE) created and launched a national public service advertising campaign designed to promote energy efficiency. The objective of the Energy Efficiency campaign was to redefine how consumers approach energy efficiency by showing that saving energy can save homeowners money.

  6. Energy Efficiency in Manufacturing Systems

    CERN Document Server

    Thiede, Sebastian

    2012-01-01

    Energy consumption is of great interest to manufacturing companies. Beyond considering individual processes and machines, the perspective on process chains and factories as a whole holds major potentials for energy efficiency improvements. To exploit these potentials, dynamic interactions of different processes as well as auxiliary equipment (e.g. compressed air generation) need to be taken into account. In addition, planning and controlling manufacturing systems require  balancing technical, economic and environmental objectives. Therefore, an innovative and comprehensive methodology – with a generic energy flow-oriented manufacturing simulation environment as a core element – is developed and embedded into a step-by-step application cycle. The concept is applied in its entirety to a wide range of case studies such as aluminium die casting, weaving mills, and printed circuit board assembly in order to demonstrate the broad applicability and the benefits that can be achieved.

  7. Energy efficient home in Lebanon

    International Nuclear Information System (INIS)

    1997-01-01

    The purpose of the study is to present new methods or new products that could save money while improving the environment in Lebanon. Cost of energy is on the increase and is predicted to increase even more in the future. Environmental issues and awareness are gaining momentum in Lebanon. With electricity production directly linked to power plants that represent about 30% of the air pollution which is also linked to health related issues. There is an intermediate need to introduce more energy efficient products in the construction industry which require less energy to operate or could be linked indirectly to energy. In this context, cost-benefit analysis of heating, light, painting, energy consumption and energy lamp burning hours in addition to fuel burner, gas and electric heater in buildings are presented in tables. Finally, there is a lack of awareness on the positive impact on the environment reflected in the saving of natural resources, reducing pollution and creation of a better living environment

  8. Thermal energy management process experiment

    Science.gov (United States)

    Ollendorf, S.

    1984-01-01

    The thermal energy management processes experiment (TEMP) will demonstrate that through the use of two-phase flow technology, thermal systems can be significantly enhanced by increasing heat transport capabilities at reduced power consumption while operating within narrow temperature limits. It has been noted that such phenomena as excess fluid puddling, priming, stratification, and surface tension effects all tend to mask the performance of two-phase flow systems in a 1-g field. The flight experiment approach would be to attack the experiment to an appropriate mounting surface with a 15 to 20 meter effective length and provide a heat input and output station in the form of heaters and a radiator. Using environmental data, the size, location, and orientation of the experiment can be optimized. The approach would be to provide a self-contained panel and mount it to the STEP through a frame. A small electronics package would be developed to interface with the STEP avionics for command and data handling. During the flight, heaters on the evaporator will be exercised to determine performance. Flight data will be evaluated against the ground tests to determine any anomalous behavior.

  9. Study of Aquifer Thermal Energy Storage

    Science.gov (United States)

    Okuyama, Masaaki; Umemiya, Hiromichi; Shibuya, Ikuko; Haga, Eiji

    Yamagata University 'Aquifer Thermal Energy Storage (ATES)' is the experimental system which has been running since 1982. From the results for along terms of experiments, we obtain many important knowledge. This paper presents the accomplishments for 16 years and the characteristics of thermal energy storage in thermal energy storage well. The conclusions show as follows. 1)In recent years, the thermal recovery factor of warm energy storage well becomes almost constant at about 60%. 2) The thermal recovery factor of cool energy storage well increases gradually and becomes at about 15%. 3) Since the ferric colloidal dam is formed in aquifer, thermal recovery factor increase year after year. 4) Back wash can remove clogging for ferric colloidal dam. 5) The apparent thermal diffusivity decrease gradually due to ferric colloidal dam.

  10. Solar energy thermalization and storage device

    Science.gov (United States)

    McClelland, J.F.

    A passive solar thermalization and thermal energy storage assembly which is visually transparent is described. The assembly consists of two substantial parallel, transparent wall members mounted in a rectangular support frame to form a liquid-tight chamber. A semitransparent thermalization plate is located in the chamber, substantially paralled to and about equidistant from the transparent wall members to thermalize solar radiation which is stored in a transparent thermal energy storage liquid which fills the chamber. A number of the devices, as modules, can be stacked together to construct a visually transparent, thermal storage wall for passive solar-heated buildings.

  11. Factors influencing energy efficiency investments in existing Swedish residential buildings

    International Nuclear Information System (INIS)

    Nair, Gireesh; Gustavsson, Leif; Mahapatra, Krushna

    2010-01-01

    We used the data from a survey conducted in 2008 of 3,000 owners of detached houses to analyse the factors that influence the adoption of investment measures to improve the energy efficiency of their buildings. For the majority of Swedish homeowners, it was important to reduce their household energy use, and most of them undertook no-cost measures as compared to investment measures. Personal attributes such as income, education, age and contextual factors, including age of the house, thermal discomfort, past investment, and perceived energy cost, influence homeowners' preference for a particular type of energy efficiency measure. The implications for promoting the implementation of energy efficiency investment measures are discussed.

  12. Energy-efficient cooking methods

    Energy Technology Data Exchange (ETDEWEB)

    De, Dilip K. [Department of Physics, University of Jos, P.M.B. 2084, Jos, Plateau State (Nigeria); Muwa Shawhatsu, N. [Department of Physics, Federal University of Technology, Yola, P.M.B. 2076, Yola, Adamawa State (Nigeria); De, N.N. [Department of Mechanical and Aerospace Engineering, The University of Texas at Arlington, Arlington, TX 76019 (United States); Ikechukwu Ajaeroh, M. [Department of Physics, University of Abuja, Abuja (Nigeria)

    2013-02-15

    Energy-efficient new cooking techniques have been developed in this research. Using a stove with 649{+-}20 W of power, the minimum heat, specific heat of transformation, and on-stove time required to completely cook 1 kg of dry beans (with water and other ingredients) and 1 kg of raw potato are found to be: 710 {+-}kJ, 613 {+-}kJ, and 1,144{+-}10 s, respectively, for beans and 287{+-}12 kJ, 200{+-}9 kJ, and 466{+-}10 s for Irish potato. Extensive researches show that these figures are, to date, the lowest amount of heat ever used to cook beans and potato and less than half the energy used in conventional cooking with a pressure cooker. The efficiency of the stove was estimated to be 52.5{+-}2 %. Discussion is made to further improve the efficiency in cooking with normal stove and solar cooker and to save food nutrients further. Our method of cooking when applied globally is expected to contribute to the clean development management (CDM) potential. The approximate values of the minimum and maximum CDM potentials are estimated to be 7.5 x 10{sup 11} and 2.2 x 10{sup 13} kg of carbon credit annually. The precise estimation CDM potential of our cooking method will be reported later.

  13. 77 FR 23224 - Renewable Energy and Energy Efficiency Advisory Committee

    Science.gov (United States)

    2012-04-18

    ... DEPARTMENT OF COMMERCE International Trade Administration Renewable Energy and Energy Efficiency... of an open meeting. SUMMARY: The Renewable Energy and Energy Efficiency Advisory Committee (RE&EEAC.... competitiveness in exporting renewable energy and energy efficiency (RE&EE) products and services, such as access...

  14. 76 FR 7815 - Renewable Energy and Energy Efficiency Advisory Committee

    Science.gov (United States)

    2011-02-11

    ... DEPARTMENT OF COMMERCE International Trade Administration Renewable Energy and Energy Efficiency... of an open meeting. SUMMARY: The Renewable Energy and Energy Efficiency Advisory Committee (RE&EEAC... programs support the competitiveness of U.S. renewable energy and energy efficiency companies, to review...

  15. 78 FR 69370 - Renewable Energy and Energy Efficiency Advisory Committee

    Science.gov (United States)

    2013-11-19

    ... DEPARTMENT OF COMMERCE International Trade Administration Renewable Energy and Energy Efficiency... of an open meeting. SUMMARY: The Renewable Energy and Energy Efficiency Advisory Committee (RE&EEAC....S. renewable energy and energy efficiency industries. The December 3, 2013 meeting of the RE&EEAC...

  16. 78 FR 2952 - Renewable Energy and Energy Efficiency Advisory Committee

    Science.gov (United States)

    2013-01-15

    ... DEPARTMENT OF COMMERCE International Trade Administration Renewable Energy and Energy Efficiency... of an open meeting. SUMMARY: The Renewable Energy and Energy Efficiency Advisory Committee (RE&EEAC... competitiveness of U.S. renewable energy and energy efficiency exports. The meeting is open to the public and the...

  17. 76 FR 54431 - Renewable Energy and Energy Efficiency Advisory Committee

    Science.gov (United States)

    2011-09-01

    ... DEPARTMENT OF COMMERCE International Trade Administration Renewable Energy and Energy Efficiency... of an Open Meeting. SUMMARY: The Renewable Energy and Energy Efficiency Advisory Committee (RE&EEAC... competitiveness of the U.S. renewable energy and energy efficiency industries, including specific challenges...

  18. 77 FR 32531 - Renewable Energy and Energy Efficiency Advisory Committee

    Science.gov (United States)

    2012-06-01

    ... DEPARTMENT OF COMMERCE International Trade Administration Renewable Energy and Energy Efficiency... of an Open Meeting. SUMMARY: The Renewable Energy and Energy Efficiency Advisory Committee (RE&EEAC... new capital for investment in the U.S. renewable energy and energy efficiency sectors, increasing the...

  19. 78 FR 78340 - Renewable Energy and Energy Efficiency Advisory Committee

    Science.gov (United States)

    2013-12-26

    ... DEPARTMENT OF COMMERCE International Trade Administration Renewable Energy and Energy Efficiency... of an Open Meeting. SUMMARY: The Renewable Energy and Energy Efficiency Advisory Committee (RE&EEAC... affecting U.S. competitiveness in exporting renewable energy and energy efficiency (RE&EE) products and...

  20. 77 FR 64112 - Office of Energy Efficiency and Renewable Energy

    Science.gov (United States)

    2012-10-18

    ... DEPARTMENT OF ENERGY Office of Energy Efficiency and Renewable Energy Nationwide Categorical Waivers of the American Recovery and Reinvestment Act AGENCY: Office of Energy Efficiency and Renewable... Efficiency and Renewable Energy, U.S. Department of Energy. [FR Doc. 2012-25636 Filed 10-17-12; 8:45 am...

  1. 76 FR 44576 - Renewable Energy and Energy Efficiency Advisory Committee

    Science.gov (United States)

    2011-07-26

    ... DEPARTMENT OF COMMERCE International Trade Administration Renewable Energy and Energy Efficiency... of an Open Meeting. SUMMARY: The Renewable Energy and Energy Efficiency Advisory Committee (RE&EEAC.... renewable energy and energy efficiency industries. The RE&EEAC held its first meeting on December 7, 2010...

  2. Heat transfer efficiency of Al2O3-MWCNT/thermal oil hybrid nanofluid as a cooling fluid in thermal and energy management applications: An experimental and theoretical investigation

    DEFF Research Database (Denmark)

    Asadi, Amin; Asadi, Meisam; Rezaniakolaei, Alireza

    2018-01-01

    efficiency of the nanofluid has been evaluated based on different figures of merit. It is revealed that using this nanofluid instead of the base fluid can be beneficial in all the studied solid concentrations and temperatures for both the internal laminar and turbulent flow regimes except the solid...... concentrations of 1 and 1.5% in internal turbulent flow regimes. The effect of adding nanoparticles on pumping power and convective heat transfer coefficient has also been theoretically investigated.......The main objective of the present study is to assess the heat transfer efficiency of Al2O3-MWCNT/thermal oil hybrid nanofluid over different temperatures (25–50 °C) and solid concentrations (0.125%–1.5%). To this end, first of all, the stability of the nano-oil has been studied through the Zeta...

  3. Revisit ocean thermal energy conversion system

    International Nuclear Information System (INIS)

    Huang, J.C.; Krock, H.J.; Oney, S.K.

    2003-01-01

    The earth, covered more than 70.8% by the ocean, receives most of its energy from the sun. Solar energy is transmitted through the atmosphere and efficiently collected and stored in the surface layer of the ocean, largely in the tropical zone. Some of the energy is re-emitted to the atmosphere to drive the hydrologic cycle and wind. The wind field returns some of the energy to the ocean in the form of waves and currents. The majority of the absorbed solar energy is stored in vertical thermal gradients near the surface layer of the ocean, most of which is in the tropical region. This thermal energy replenished each day by the sun in the tropical ocean represents a tremendous pollution-free energy resource for human civilization. Ocean Thermal Energy Conversion (OTEC) technology refers to a mechanical system that utilizes the natural temperature gradient that exists in the tropical ocean between the warm surface water and the deep cold water, to generate electricity and produce other economically valuable by-products. The science and engineering behind OTEC have been studied in the US since the mid-seventies, supported early by the U.S. Government and later by State and private industries. There are two general types of OTEC designs: closed-cycle plants utilize the evaporation of a working fluid, such as ammonia or propylene, to drive the turbine-generator, and open-cycle plants use steam from evaporated sea water to run the turbine. Another commonly known design, hybrid plants, is a combination of the two. OTEC requires relatively low operation and maintenance costs and no fossil fuel consumption. OTEC system possesses a formidable potential capacity for renewable energy and offers a significant elimination of greenhouse gases in producing power. In addition to electricity and drinking water, an OTEC system can produce many valuable by-products and side-utilizations, such as: hydrogen, air-conditioning, ice, aquaculture, and agriculture, etc. The potential of these

  4. Energy efficiency of housing for older citizens: Does it matter?

    International Nuclear Information System (INIS)

    Miller, Wendy; Vine, Desley; Amin, Zakaria

    2017-01-01

    Global population ageing has significant implications for public policy in areas such as health, housing and economic security. The notion of housing as a public health issue is not new, yet very little research has examined the links between housing specifically built for older people, energy performance and occupant health and economic security. Utilising a case study approach, this research examined the interplay between the energy efficiency of housing explicitly designed for this demographic, the thermal efficiency of their dwellings, and the impact on internal temperatures and monthly energy costs. The study shows that the thermal efficiency of the dwellings is not the same across all dwellings, impacting the internal temperatures experienced by the elderly occupants and their finances. This has implications for energy efficiency policy, policy governing the energy performance of buildings specifically designed for older people, as well as the mandatory disclosure of building performance. The study highlights in particular the need for energy policy to be further refined to link the thermal performance requirements of buildings to the broader health care plan and specific needs of older people. - Highlights: • Housing quality impacts on the health and economic wellbeing of older people. • This demographic can have limited capacity to manage and pay for thermal comfort. • Building thermal performance is not disclosed or linked to occupants' health care. • Energy and health policies need to be much more closely aligned. • This can be through building regulations, mandatory disclosure and heat wave plans.

  5. Temperature Distribution and Thermal Performance of an Aquifer Thermal Energy Storage System

    Science.gov (United States)

    Ganguly, Sayantan

    2017-04-01

    Energy conservation and storage has become very crucial to make use of excess energy during times of future demand. Excess thermal energy can be captured and stored in aquifers and this technique is termed as Aquifer Thermal Energy Storage (ATES). Storing seasonal thermal energy in water by injecting it into subsurface and extracting in time of demand is the principle of an ATES system. Using ATES systems leads to energy savings, reduces the dependency on fossil fuels and thus leads to reduction in greenhouse gas emission. This study numerically models an ATES system to store seasonal thermal energy and evaluates the performance of it. A 3D thermo-hydrogeological numerical model for a confined ATES system is presented in this study. The model includes heat transport processes of advection, conduction and heat loss to confining rock media. The model also takes into account regional groundwater flow in the aquifer, geothermal gradient and anisotropy in the aquifer. Results show that thermal injection into the aquifer results in the generation of a thermal-front which grows in size with time. Premature thermal-breakthrough causes thermal interference in the system when the thermal-front reaches the production well and consequences in the fall of system performance and hence should be avoided. This study models the transient temperature distribution in the aquifer for different flow and geological conditions. This may be effectively used in designing an efficient ATES project by ensuring safety from thermal-breakthrough while catering to the energy demand. Based on the model results a safe well spacing is proposed. The thermal energy discharged by the system is determined and strategy to avoid the premature thermal-breakthrough in critical cases is discussed. The present numerical model is applied to simulate an experimental field study which is found to approximate the field results quite well.

  6. Global status report on energy efficiency 2008

    NARCIS (Netherlands)

    Blok, K.; van Breevoort, P.; Roes, A.L.; Coenraads, R.; Müller, N.

    2008-01-01

    There is wide agreement that energy efficiency improvement is one of the key strategies to achieve greater sustainability of the energy system. In the past, the contribution of energy efficiency has already been considerable.Without the energy efficiency improvements achieved since the 1970s,

  7. 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.

  8. Thermal energy storage apparatus, controllers and thermal energy storage control methods

    Science.gov (United States)

    Hammerstrom, Donald J.

    2016-05-03

    Thermal energy storage apparatus, controllers and thermal energy storage control methods are described. According to one aspect, a thermal energy storage apparatus controller includes processing circuitry configured to access first information which is indicative of surpluses and deficiencies of electrical energy upon an electrical power system at a plurality of moments in time, access second information which is indicative of temperature of a thermal energy storage medium at a plurality of moments in time, and use the first and second information to control an amount of electrical energy which is utilized by a heating element to heat the thermal energy storage medium at a plurality of moments in time.

  9. Energy Storage Thermal Safety | Transportation Research | NREL

    Science.gov (United States)

    reaction/thermal runaway, internal short circuit, and electrical/chemical/thermal network models are used contributions to the U.S. Department of Energy's Computer-Aided Engineering of Batteries (CAEBAT) project Li-ion battery geometries. Chemical components in Li-ion batteries become thermally unstable when

  10. Solar-thermal conversion and thermal energy storage of graphene foam-based composite

    KAUST Repository

    Zhang, Lianbin

    2016-07-11

    Among various utilizations of solar energy, solar-thermal conversion has recently gained renewed research interest due to its extremely high energy efficiency. However, one limiting factor common to all solar-based energy conversion technologies is the intermittent nature of solar irradiation, which makes them unable to stand-alone to satisfy continuous energy need. Herein, we report a three-dimensional (3D) graphene foam and phase change material (PCM) composite for the seamlessly combined solar-thermal conversion and thermal storage for sustained energy release. The composite is obtained by infiltrating the 3D graphene foam with a commonly used PCM, paraffin wax. The high macroporosity and low density of the graphene foam allow for high weight fraction of the PCM to be incorporated, which enhances heat storage capacity of the composite. The interconnected graphene sheets in the composite provide (1) the solar-thermal conversion capability, (2) high thermal conductivity and (3) form stability of the composite. Under light irradiation, the composite effectively collects and converts the light energy into thermal energy, and the converted thermal energy is stored in the PCM and released in an elongated period of time for sustained utilization. This study provides a promising route for sustainable utilization of solar energy.

  11. Solar-thermal conversion and thermal energy storage of graphene foam-based composites.

    Science.gov (United States)

    Zhang, Lianbin; Li, Renyuan; Tang, Bo; Wang, Peng

    2016-08-14

    Among various utilizations of solar energy, solar-thermal conversion has recently gained renewed research interest due to its extremely high energy efficiency. However, one limiting factor common to all solar-based energy conversion technologies is the intermittent nature of solar irradiation, which makes them unable to stand-alone to satisfy the continuous energy need. Herein, we report a three-dimensional (3D) graphene foam and phase change material (PCM) composite for the seamlessly combined solar-thermal conversion and thermal storage for sustained energy release. The composite is obtained by infiltrating the 3D graphene foam with a commonly used PCM, paraffin wax. The high macroporosity and low density of the graphene foam allow for high weight fraction of the PCM to be incorporated, which enhances the heat storage capacity of the composite. The interconnected graphene sheets in the composite provide (1) the solar-thermal conversion capability, (2) high thermal conductivity and (3) form stability of the composite. Under light irradiation, the composite effectively collects and converts the light energy into thermal energy, and the converted thermal energy is stored in the PCM and released in an elongated period of time for sustained utilization. This study provides a promising route for sustainable utilization of solar energy.

  12. Energy efficiency networks; Energieeffizienz-Netzwerke

    Energy Technology Data Exchange (ETDEWEB)

    Gruber, Anna [Forschungsgesellschaft fuer Energiewirtschaft mbH (FfE GmbH), Muenchen (Germany)

    2011-07-01

    Energy efficiency networks are an attractive method to increase the energy efficiency and to reduce the costs and CO{sub 2} emissions of the companies operating in this network. A special feature of the energy efficiency networks is the exchange of experiences and training of the energy managers. Energy efficiency networks consist of about ten to fifteen locally domiciled companies. During the project period of three to four years, there are two main phases. In the first phase, the initial consultation phase, the actual state of a company is captured, and measures to increase the efficiency and energy conservation are identified. Parallel to this, in the second phase every three months a meeting with the participating companies takes place. Experience exchange and implementation of energy efficiency measures are the focus of these meetings. Initial studies show that the increase of the energy efficiency during participating in the energy efficiency network almost can be doubled in comparison to the average of the industry.

  13. Rapid charging of thermal energy storage materials through plasmonic heating.

    Science.gov (United States)

    Wang, Zhongyong; Tao, Peng; Liu, Yang; Xu, Hao; Ye, Qinxian; Hu, Hang; Song, Chengyi; Chen, Zhaoping; Shang, Wen; Deng, Tao

    2014-09-01

    Direct collection, conversion and storage of solar radiation as thermal energy are crucial to the efficient utilization of renewable solar energy and the reduction of global carbon footprint. This work reports a facile approach for rapid and efficient charging of thermal energy storage materials by the instant and intense photothermal effect of uniformly distributed plasmonic nanoparticles. Upon illumination with both green laser light and sunlight, the prepared plasmonic nanocomposites with volumetric ppm level of filler concentration demonstrated a faster heating rate, a higher heating temperature and a larger heating area than the conventional thermal diffusion based approach. With controlled dispersion, we further demonstrated that the light-to-heat conversion and thermal storage properties of the plasmonic nanocomposites can be fine-tuned by engineering the composition of the nanocomposites.

  14. USE Efficiency -- Universities and Students for Energy Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Melandri, Daniela

    2010-09-15

    Universities and Student for Energy Efficiency is a European Project within the Intelligent Energy Programme. It intends to create a common stream for energy efficiency systems in university buildings. Universities and students are proposed as shining examples for energy efficiency solutions and behaviour. The Project involves 10 countries and has the aim to improve energy efficiency in university buildings. Students are the main actors of the project together with professors and technicians. To act on students means to act on direct future market players in diffusion of public opinions. A strong communication action supports the succeeding of the action.

  15. Potential energy savings and thermal comfort

    DEFF Research Database (Denmark)

    Jensen, Karsten Ingerslev; Rudbeck, Claus Christian; Schultz, Jørgen Munthe

    1996-01-01

    The simulation results on the energy saving potential and influence on indoor thermal comfort by replacement of common windows with aerogel windows as well as commercial low-energy windows are described and analysed.......The simulation results on the energy saving potential and influence on indoor thermal comfort by replacement of common windows with aerogel windows as well as commercial low-energy windows are described and analysed....

  16. Means of increasing efficiency of CPC solar energy collector

    Science.gov (United States)

    Chao, B.T.; Rabl, A.

    1975-06-27

    A device is provided for improving the thermal efficiency of a cylindrical radiant energy collector. A channel is placed next to and in close proximity to the nonreflective side of an energy reflective wall of a cylindrical collector. A coolant is piped through the channel and removes a portion of the nonreflective energy incident on the wall which is absorbed by the wall. The energy transferred to the coolant may be utilized in a useful manner.

  17. Concrete thermal energy storage for steam generation

    DEFF Research Database (Denmark)

    Singh, Shobhana; Sørensen, Kim

    2017-01-01

    Establishing enhancement methods to develop cost-effective thermal energy storage technology requires a detailed analysis. In this paper, a numerical investigation of the concrete based thermal energy storage system is carried out. The storage system consists of a heat transfer fluid flowing inside...

  18. Design Considerations of a Solid State Thermal Energy Storage

    Science.gov (United States)

    Janbozorgi, Mohammad; Houssainy, Sammy; Thacker, Ariana; Ip, Peggy; Ismail, Walid; Kavehpour, Pirouz

    2016-11-01

    With the growing governmental restrictions on carbon emission, renewable energies are becoming more prevalent. A reliable use of a renewable source however requires a built-in storage to overcome the inherent intermittent nature of the available energy. Thermal design of a solid state energy storage has been investigated for optimal performance. The impact of flow regime, laminar vs. turbulent, on the design and sizing of the system is also studied. The implications of low thermal conductivity of the storage material are discussed and a design that maximizes the round trip efficiency is presented. This study was supported by Award No. EPC-14-027 Granted by California Energy Commission (CEC).

  19. Thermodynamic limits of energy harvesting from outgoing thermal radiation.

    Science.gov (United States)

    Buddhiraju, Siddharth; Santhanam, Parthiban; Fan, Shanhui

    2018-04-17

    We derive the thermodynamic limits of harvesting power from the outgoing thermal radiation from the ambient to the cold outer space. The derivations are based on a duality relation between thermal engines that harvest solar radiation and those that harvest outgoing thermal radiation. In particular, we derive the ultimate limit for harvesting outgoing thermal radiation, which is analogous to the Landsberg limit for solar energy harvesting, and show that the ultimate limit far exceeds what was previously thought to be possible. As an extension of our work, we also derive the ultimate limit of efficiency of thermophotovoltaic systems.

  20. Efficient thermal management for multiprocessor systems

    OpenAIRE

    Coşkun, Ayşe Kıvılcım

    2009-01-01

    High temperatures and large thermal variations on the die create severe challenges in system reliability, performance, leakage power, and cooling costs. Designing for worst-case thermal conditions is highly costly and time-consuming. Therefore, dynamic thermal management methods are needed to maintain safe temperature levels during execution. Conventional management techniques sacrifice performance to control temperature and only consider the hot spots, neglecting the effects of thermal varia...

  1. Energy analysis of thermal energy storages with grid configurations

    International Nuclear Information System (INIS)

    Rezaie, Behnaz; Reddy, Bale V.; Rosen, Marc A.

    2014-01-01

    Highlights: • Grid configurations of TESs are developed and assessed. • Characteristics of various configurations of TESs are developed as functions of properties. • Functions for the discharge temperature and the discharge energy of the TES are developed. - Abstract: In some thermal networks like district energy systems, there can exist conditions, depending on space availability, economics, project requirements, insulation, storing media type and other issues, for which it may be advantageous to utilize several thermal energy storages (TESs) instead of one. Here, various configurations for multiple TESs are proposed and investigated. Significant parameters for a TES, or a set of TESs, include discharging temperature and recovered energy. First, one TES is modeled to determine the final temperature, energy recovery, and energy efficiency. Next, characteristics for various grid configurations of multiple TESs are developed as functions of TES characteristics (e.g., charging and discharging temperatures and energy quantities). Series, parallel and comprehensive grid TES configurations are considered. In the parallel configuration, the TESs behave independently. This suggests that the TES can consist of different storage media types and sizes, and that there is no restriction on initial temperature of the TES. In the series configuration, the situation is different because the TESs are connected directly or indirectly through a heat exchanger. If there is no heat exchanger between the TESs, the TES storage media should be the same, because the outlet of one TES in the series is the inlet to the next. The initial temperature of the second TES must be smaller than the discharge temperature of the first. There is no restriction on the TES size for series configurations. The general grid configuration is observed to exhibit characteristics of both series and parallel configurations

  2. Energy efficiency in the British housing stock: Energy demand and the Homes Energy Efficiency Database

    International Nuclear Information System (INIS)

    Hamilton, Ian G.; Steadman, Philip J.; Bruhns, Harry; Summerfield, Alex J.; Lowe, Robert

    2013-01-01

    The UK Government has unveiled an ambitious retrofit programme that seeks significant improvement to the energy efficiency of the housing stock. High quality data on the energy efficiency of buildings and their related energy demand is critical to supporting and targeting investment in energy efficiency. Using existing home improvement programmes over the past 15 years, the UK Government has brought together data on energy efficiency retrofits in approximately 13 million homes into the Homes Energy Efficiency Database (HEED), along with annual metered gas and electricity use for the period of 2004–2007. This paper describes the HEED sample and assesses its representativeness in terms of dwelling characteristics, the energy demand of different energy performance levels using linked gas and electricity meter data, along with an analysis of the impact retrofit measures has on energy demand. Energy savings are shown to be associated with the installation of loft and cavity insulation, and glazing and boiler replacement. The analysis illustrates this source of ‘in-action’ data can be used to provide empirical estimates of impacts of energy efficiency retrofit on energy demand and provides a source of empirical data from which to support the development of national housing energy efficiency retrofit policies. - Highlights: • The energy efficiency level for 50% of the British housing stock is described. • Energy demand is influenced by size and age and energy performance. • Housing retrofits (e.g. cavity insulation, glazing and boiler replacements) save energy. • Historic differences in energy performance show persistent long-term energy savings

  3. Energy Efficiency of Low-Temperature Deaeration of Makeup Water for a District Heating System

    Energy Technology Data Exchange (ETDEWEB)

    Sharapov, V. I., E-mail: vlad-sharapov2008@yandex.ru; Kudryavtseva, E. V. [Ulyanovsk State Technical University (Russian Federation)

    2016-07-15

    It is shown that the temperature of makeup water in district heating systems has a strong effect on the energy efficiency of turbines of thermal power plants. A low-temperature deaeration process that considerably improves the energy efficiency of thermal power plants is developed. The desorbing agent is the gas supplied to the burners of the boiler. The energy efficiency of the process for a typical unit of thermal power plant is assessed.

  4. Thermal energy systems design and analysis

    CERN Document Server

    Penoncello, Steven G

    2015-01-01

    IntroductionThermal Energy Systems Design and AnalysisSoftwareThermal Energy System TopicsUnits and Unit SystemsThermophysical PropertiesEngineering DesignEngineering EconomicsIntroductionCommon Engineering Economics NomenclatureEconomic Analysis Tool: The Cash Flow DiagramTime Value of MoneyTime Value of Money ExamplesUsing Software to Calculate Interest FactorsEconomic Decision MakingDepreciation and TaxesProblemsAnalysis of Thermal Energy SystemsIntroductionNomenclatureThermophysical Properties of SubstancesSuggested Thermal Energy Systems Analysis ProcedureConserved and Balanced QuantitiesConservation of MassConservation of Energy (The First Law of Thermodynamics)Entropy Balance (The Second Law of Thermodynamics)Exergy Balance: The Combined LawEnergy and Exergy Analysis of Thermal Energy CyclesDetailed Analysis of Thermal Energy CyclesProblemsFluid Transport in Thermal Energy SystemsIntroductionPiping and Tubing StandardsFluid Flow FundamentalsValves and FittingsDesign and Analysis of Pipe NetworksEconomi...

  5. Geospatial Technologies to Improve Urban Energy Efficiency

    Directory of Open Access Journals (Sweden)

    Bharanidharan Hemachandran

    2011-07-01

    Full Text Available The HEAT (Home Energy Assessment Technologies pilot project is a FREE Geoweb mapping service, designed to empower the urban energy efficiency movement by allowing residents to visualize the amount and location of waste heat leaving their homes and communities as easily as clicking on their house in Google Maps. HEAT incorporates Geospatial solutions for residential waste heat monitoring using Geographic Object-Based Image Analysis (GEOBIA and Canadian built Thermal Airborne Broadband Imager technology (TABI-320 to provide users with timely, in-depth, easy to use, location-specific waste-heat information; as well as opportunities to save their money and reduce their green-house-gas emissions. We first report on the HEAT Phase I pilot project which evaluates 368 residences in the Brentwood community of Calgary, Alberta, Canada, and describe the development and implementation of interactive waste heat maps, energy use models, a Hot Spot tool able to view the 6+ hottest locations on each home and a new HEAT Score for inter-city waste heat comparisons. We then describe current challenges, lessons learned and new solutions as we begin Phase II and scale from 368 to 300,000+ homes with the newly developed TABI-1800. Specifically, we introduce a new object-based mosaicing strategy, an adaptation of Emissivity Modulation to correct for emissivity differences, a new Thermal Urban Road Normalization (TURN technique to correct for scene-wide microclimatic variation. We also describe a new Carbon Score and opportunities to update city cadastral errors with automatically defined thermal house objects.

  6. Establishing an energy efficiency recommendation for commercial boilers

    International Nuclear Information System (INIS)

    Ware, Michelle J.

    2000-01-01

    To assist the federal government in meeting its energy reduction goals, President Clinton's Executive Order 12902 established the Procurement Challenge, which directed all federal agencies to purchase equipment within the top 25th percentile of efficiency. Under the direction of DOE's Federal Energy Management Program (FEMP), the Procurement Challenge's goal is to create efficiency recommendations for all energy-using products that could substantially impact the government's energy reduction goals, like commercial boilers. A typical 5,000,000 Btuh boiler, with a thermal efficiency of 83.2%, can have lifetime energy cost savings of$40,000 when compared to a boiler with a thermal efficiency of 78%. For the federal market, which makes up 2% of the boiler market, this means lifetime energy cost savings of over$25,600,000. To establish efficiency recommendations, FEMP uses standardized performance ratings for products sold in the marketplace. Currently, the boiler industry uses combustion efficiency and, sometimes, thermal efficiency performance measures when specifying a commercial boiler. For many years, the industry has used these efficiency measures interchangeably, causing confusion about boiler performance measurements, and making it difficult for FEMP to establish the top 25th percentile of efficiency. This paper will illustrate the method used to establish FEMP's recommendation for boilers. The method involved defining a correlation between thermal and combustion efficiency among boiler classifications; using the correlation to model a data set of all the boiler types available in the market; and identifying how the correlation affected the top 25th percentile analysis. The paper also will discuss the applicability of this method for evaluating other equipment for which there are limited data on performance ratings

  7. Compare of Energy Efficiency of Windows in Aalborg and Chongqing

    DEFF Research Database (Denmark)

    Lin, Zhenguo; Heiselberg, Per; Yao, Runming

    2007-01-01

    Focus on window's energy efficiency, this paper compared the difference of windows in Aalborg and Chongqing. The author analysed the designing process, the thermal insulation performances, the sun shading devices and the ventilation of windows in Aalborg and Chongqing respectively. Furthermore......, the author explored the reasons for window problems in Chongqing, found out the main barriers to overcome and measures to take for solving the problem. Deeper analysis should be made before the energy efficient windows of Aalborg used in Chongqing....

  8. Mechanical efficiency of the energy release during a steam explosion

    International Nuclear Information System (INIS)

    Krieg, R.

    1997-01-01

    The mechanical processes during the expansion phase of a steam explosion with intimately fragmented liquid particles is investigated based on elementary principles and analytical solutions. During a short load pulse, the different densities of the water and the melted particles lead to different velocities. After the load pulse, viscosity effects lead to a slow down of the higher velocities and to a corresponding reconversion of the kinetic energy of the mixture into thermal energy. It is shown that both effects are proportional to each other. The ratio between the residual and the applied mechanical energy is defined as the mechanical efficiency of the steam explosion. Using data typical for a steam explosion in a pressurized water reactor, mechanical efficiencies of <50% are estimated. Considering that the thermodynamic efficiencies are quite limited, the very low conversion rates from thermal energy into mechanical energy observed during steam explosion experiments can be more easily understood

  9. Increasing the efficiency of solar thermal panels

    Science.gov (United States)

    Dobrnjac, M.; Latinović, T.; Dobrnjac, S.; Živković, P.

    2016-08-01

    The popularity of solar heating systems is increasing for several reasons. These systems are reliable, adaptable and pollution-free, because the renewable solar energy is used. There are many variants of solar systems in the market mainly constructed with copper pipes and absorbers with different quality of absorption surface. Taking into account the advantages and disadvantages of existing solutions, in order to increase efficiency and improve the design of solar panel, the innovative solution has been done. This new solar panel presents connection of an attractive design and the use of constructive appropriate materials with special geometric shapes. Hydraulic and thermotechnical tests that have been performed on this panel showed high hydraulic and structural stability. Further development of the solar panel will be done in the future in order to improve some noticed disadvantages.

  10. Flexible operation of thermal plants with integrated energy storage technologies

    Science.gov (United States)

    Koytsoumpa, Efthymia Ioanna; Bergins, Christian; Kakaras, Emmanouil

    2017-08-01

    The energy system in the EU requires today as well as towards 2030 to 2050 significant amounts of thermal power plants in combination with the continuously increasing share of Renewables Energy Sources (RES) to assure the grid stability and to secure electricity supply as well as to provide heat. The operation of the conventional fleet should be harmonised with the fluctuating renewable energy sources and their intermittent electricity production. Flexible thermal plants should be able to reach their lowest minimum load capabilities while keeping the efficiency drop moderate as well as to increase their ramp up and down rates. A novel approach for integrating energy storage as an evolutionary measure to overcome many of the challenges, which arise from increasing RES and balancing with thermal power is presented. Energy storage technologies such as Power to Fuel, Liquid Air Energy Storage and Batteries are investigated in conjunction with flexible power plants.

  11. Energy efficient elevators and escalators

    Energy Technology Data Exchange (ETDEWEB)

    Patrao, Carlos; Fong, Joao; Almeida, Anibal de (Dep. Electrical Engineering, Univ. of Coimbra, Coimbra (Portugal)); Rivet, Luc

    2009-07-01

    Elevators and escalators are the crucial element that makes it practical to live and work several floors above ground - more than 4,3 million units are installed in Europe. Due to ageing of the European population the installation of elevators in single family houses is experiencing a significant growth, as well as equipping existing buildings. Elevators use about 4% of the electricity in tertiary sector buildings. High untapped saving potentials exist with respect to energy-efficient technologies, investment decisions and behavioural approaches, in these sectors. This paper presents preliminary results from the IEE project E4, whose overall objective is the improvement of the energy performance of elevators and escalators, in tertiary sector buildings and in multi family residential buildings. The project is characterizing people conveyors electricity consumption in the tertiary sector and in residential buildings in the EU. The installed park is characterised by a survey among elevators national associations in each country. An assessment of the barriers has been made in the first phase of the project and will be presented. Monitoring campaigns in elevators and escalators are being conducted in each country according to a common developed methodology. More than fifty elevators and escalators will be audited. This will allow the collection of load curves (start up, travel up and down, travel full and empty), including the characterization of standby consumption. Standby consumption of an elevator can represent up to 80% of the total energy consumed per year, and can be drastically reduced. This paper presents the preliminary results of the first ten audits performed in Portugal by Isr-UC.

  12. Thermal energy accumulators. A bibliographical study

    International Nuclear Information System (INIS)

    Charlety, Paul

    1971-01-01

    Energy storage is a challenge, notably for spacecraft, submarines and non-polluting automotive vehicles. After a comparison of mass energies of different principles of energy accumulation (magnetic, electrostatic, solid elasticity, kinetic energy, gaseous elasticity, electro-chemistry, sensitive heat, freezing heat, fuels, radioactivity, nuclear fission or fusion, mass energy), the author discusses the choice of thermal storage, presents the main bodies used for thermal energy accumulation (molten salts such as lithium hydride or lithium salt eutectics, or other compounds such as alumina, paraffins), and gives an overview of the main theoretical problems [fr

  13. Market conditions affecting energy efficiency investments

    International Nuclear Information System (INIS)

    Seabright, J.

    1996-01-01

    The global energy efficiency market is growing, due in part to energy sector and macroeconomic reforms and increased awareness of the environmental benefits of energy efficiency. Many countries have promoted open, competitive markets, thereby stimulating economic growth. They have reduced or removed subsidies on energy prices, and governments have initiated energy conservation programs that have spurred the wider adoption of energy efficiency technologies. The market outlook for energy efficiency is quite positive. The global market for end-use energy efficiency in the industrial, residential and commercial sectors is now estimated to total more than $34 billion per year. There is still enormous technical potential to implement energy conservation measures and to upgrade to the best available technologies for new investments. For many technologies, energy-efficient designs now represent less than 10--20% of new product sales. Thus, creating favorable market conditions should be a priority. There are a number of actions that can be taken to create favorable market conditions for investing in energy efficiency. Fostering a market-oriented energy sector will lead to energy prices that reflect the true cost of supply. Policy initiatives should address known market failures and should support energy efficiency initiatives. And market transformation for energy efficiency products and services can be facilitated by creating an institutional and legal structure that favors commercially-oriented entities

  14. Optimization of thermal insulation to achieve energy savings in low energy house (refurbishment)

    International Nuclear Information System (INIS)

    Bojić, Milorad; Miletić, Marko; Bojić, Ljubiša

    2014-01-01

    Highlights: • For buildings that require heating, a thickness of their thermal insulation is optimized. • The objective was to improve energy efficiency of the building. • The optimization is performed by using EnergyPlus and Hooke–Jeeves method. • The embodied energy of thermal insulation and the entire life cycle of the house are taken into account. - Abstract: Due to the current environmental situation, saving energy and reducing CO 2 emission have become the leading drive in modern research. For buildings that require heating, one of the solutions is to optimize a thickness of their thermal insulation and thus improve energy efficiency and reduce energy needs. In this paper, for a small residential house in Serbia, an optimization in the thickness of its thermal insulation layer is investigated by using EnergyPlus software and Hooke–Jeeves direct search method. The embodied energy of thermal insulation is taken into account. The optimization is done for the entire life cycle of thermal insulation. The results show the optimal thickness of thermal insulation that yields the minimum primary energy consumption

  15. Thermal performance and heat transport in aquifer thermal energy storage

    Science.gov (United States)

    Sommer, W. T.; Doornenbal, P. J.; Drijver, B. C.; van Gaans, P. F. M.; Leusbrock, I.; Grotenhuis, J. T. C.; Rijnaarts, H. H. M.

    2014-01-01

    Aquifer thermal energy storage (ATES) is used for seasonal storage of large quantities of thermal energy. Due to the increasing demand for sustainable energy, the number of ATES systems has increased rapidly, which has raised questions on the effect of ATES systems on their surroundings as well as their thermal performance. Furthermore, the increasing density of systems generates concern regarding thermal interference between the wells of one system and between neighboring systems. An assessment is made of (1) the thermal storage performance, and (2) the heat transport around the wells of an existing ATES system in the Netherlands. Reconstruction of flow rates and injection and extraction temperatures from hourly logs of operational data from 2005 to 2012 show that the average thermal recovery is 82 % for cold storage and 68 % for heat storage. Subsurface heat transport is monitored using distributed temperature sensing. Although the measurements reveal unequal distribution of flow rate over different parts of the well screen and preferential flow due to aquifer heterogeneity, sufficient well spacing has avoided thermal interference. However, oversizing of well spacing may limit the number of systems that can be realized in an area and lower the potential of ATES.

  16. Theoretical efficiency limits for thermoradiative energy conversion

    International Nuclear Information System (INIS)

    Strandberg, Rune

    2015-01-01

    A new method to produce electricity from heat called thermoradiative energy conversion is analyzed. The method is based on sustaining a difference in the chemical potential for electron populations above and below an energy gap and let this difference drive a current through an electric circuit. The difference in chemical potential originates from an imbalance in the excitation and de-excitation of electrons across the energy gap. The method has similarities to thermophotovoltaics and conventional photovoltaics. While photovoltaic cells absorb thermal radiation from a body with higher temperature than the cell itself, thermoradiative cells are hot during operation and emit a net outflow of photons to colder surroundings. A thermoradiative cell with an energy gap of 0.25 eV at a temperature of 500 K in surroundings at 300 K is found to have a theoretical efficiency limit of 33.2%. For a high-temperature thermoradiative cell with an energy gap of 0.4 eV, a theoretical efficiency close to 50% is found while the cell produces 1000 W/m 2 has a temperature of 1000 K and is placed in surroundings with a temperature of 300 K. Some aspects related to the practical implementation of the concept are discussed and some challenges are addressed. It is, for example, obvious that there is an upper boundary for the temperature under which solid state devices can work properly over time. No conclusions are drawn with regard to such practical boundaries, because the work is aimed at establishing upper limits for ideal thermoradiative devices

  17. Micro rectennas: Brownian ratchets for thermal-energy harvesting

    International Nuclear Information System (INIS)

    Pan, Y.; Powell, C. V.; Balocco, C.; Song, A. M.

    2014-01-01

    We experimentally demonstrated the operation of a rectenna for harvesting thermal (blackbody) radiation and converting it into dc electric power. The device integrates an ultrafast rectifier, the self-switching nanodiode, with a wideband log-periodic spiral microantenna. The radiation from the thermal source drives the rectenna out of thermal equilibrium, permitting the rectification of the excess thermal fluctuations from the antenna. The power conversion efficiency increases with the source temperatures up to 0.02% at 973 K. The low efficiency is attributed mainly to the impedance mismatch between antenna and rectifier, and partially to the large field of view of the antenna. Our device not only opens a potential solution for harvesting thermal energy but also provides a platform for experimenting with Brownian ratchets

  18. Micro rectennas: Brownian ratchets for thermal-energy harvesting

    Science.gov (United States)

    Pan, Y.; Powell, C. V.; Song, A. M.; Balocco, C.

    2014-12-01

    We experimentally demonstrated the operation of a rectenna for harvesting thermal (blackbody) radiation and converting it into dc electric power. The device integrates an ultrafast rectifier, the self-switching nanodiode, with a wideband log-periodic spiral microantenna. The radiation from the thermal source drives the rectenna out of thermal equilibrium, permitting the rectification of the excess thermal fluctuations from the antenna. The power conversion efficiency increases with the source temperatures up to 0.02% at 973 K. The low efficiency is attributed mainly to the impedance mismatch between antenna and rectifier, and partially to the large field of view of the antenna. Our device not only opens a potential solution for harvesting thermal energy but also provides a platform for experimenting with Brownian ratchets.

  19. Micro rectennas: Brownian ratchets for thermal-energy harvesting

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Y.; Powell, C. V.; Balocco, C., E-mail: claudio.balocco@durham.ac.uk [School of Engineering and Computing Sciences, Durham University, Durham DH1 3LE (United Kingdom); Song, A. M. [School of Electrical and Electronic Engineering, University of Manchester, Manchester M13 9PL (United Kingdom)

    2014-12-22

    We experimentally demonstrated the operation of a rectenna for harvesting thermal (blackbody) radiation and converting it into dc electric power. The device integrates an ultrafast rectifier, the self-switching nanodiode, with a wideband log-periodic spiral microantenna. The radiation from the thermal source drives the rectenna out of thermal equilibrium, permitting the rectification of the excess thermal fluctuations from the antenna. The power conversion efficiency increases with the source temperatures up to 0.02% at 973 K. The low efficiency is attributed mainly to the impedance mismatch between antenna and rectifier, and partially to the large field of view of the antenna. Our device not only opens a potential solution for harvesting thermal energy but also provides a platform for experimenting with Brownian ratchets.

  20. Energy efficiency: from principles to reality

    International Nuclear Information System (INIS)

    Baudry, Paul; Ballot-Miguel, Benedicte; Binet, Guillaume; Bordigoni, Mathieu; Decellas, Fabrice; Hauser, Chantal; Hita, Laurent; Laurent, Marie-Helene; Osso, Dominique; Peureux, Jean-Louis; Pham Van Cang, Christian

    2015-01-01

    This collective publication proposes a comprehensive overview of issues related to energy efficiency: associated stakes, methods of assessment of energy savings and of their costs, methods of action for energy efficiency policies, application in the housing, office building and industry sectors based on energy consumption modes in these different sectors, and main technologies aimed at improving energy efficiency. The first chapter proposes an historical perspective on energy, outlines the crucial role of energy efficiency in today's and tomorrow's contexts, and discusses which are the different levers of action to increase this efficiency. The next chapters address methods of assessment of energy efficiency, identify and discuss the use of different potential sources of energy saving, propose an overview of the various objectives and instruments of policies for energy efficiency, and address the issue of energy efficiency in the housing sector, in the office building sector, and in the industry sector by indicating the current levels of energy consumption, by identifying the various potential sources of energy saving, and by indicating available technologies aimed at improving energy efficiency

  1. General Motors LLC Final Project Report: Improving Energy Efficiency by Developing Components for Distributed Cooling and Heating Based on Thermal Comfort Modeling

    Energy Technology Data Exchange (ETDEWEB)

    Bozeman, Jeffrey [General Motors LLC, Detroit, MI (United States); Chen, Kuo-Huey [General Motors LLC, Detroit, MI (United States)

    2014-12-09

    On November 3, 2009, General Motors (GM) accepted U.S. Department of Energy (DOE) Cooperative Agreement award number DE-EE0000014 from the National Energy Technology Laboratory (NETL). GM was selected to execute a three-year cost shared research and development project on Solid State Energy Conversion for Vehicular Heating, Ventilation & Air Conditioning (HVAC) and for Waste Heat Recovery.

  2. Health, Energy Efficiency and Climate Change

    Science.gov (United States)

    Climate change is becoming a driving force for improving energy efficiency because saving energy can help reduce the greenhouse gas emissions that contribute to climate change. However, it is important to balance energy saving measures with ventilation...

  3. Scalable, "Dip-and-Dry" Fabrication of a Wide-Angle Plasmonic Selective Absorber for High-Efficiency Solar-Thermal Energy Conversion.

    Science.gov (United States)

    Mandal, Jyotirmoy; Wang, Derek; Overvig, Adam C; Shi, Norman N; Paley, Daniel; Zangiabadi, Amirali; Cheng, Qian; Barmak, Katayun; Yu, Nanfang; Yang, Yuan

    2017-11-01

    A galvanic-displacement-reaction-based, room-temperature "dip-and-dry" technique is demonstrated for fabricating selectively solar-absorbing plasmonic-nanoparticle-coated foils (PNFs). The technique, which allows for facile tuning of the PNFs' spectral reflectance to suit different radiative and thermal environments, yields PNFs which exhibit excellent, wide-angle solar absorptance (0.96 at 15°, to 0.97 at 35°, to 0.79 at 80°), and low hemispherical thermal emittance (0.10) without the aid of antireflection coatings. The thermal emittance is on par with those of notable selective solar absorbers (SSAs) in the literature, while the wide-angle solar absorptance surpasses those of previously reported SSAs with comparable optical selectivities. In addition, the PNFs show promising mechanical and thermal stabilities at temperatures of up to 200 °C. Along with the performance of the PNFs, the simplicity, inexpensiveness, and environmental friendliness of the "dip-and-dry" technique makes it an appealing alternative to current methods for fabricating selective solar absorbers. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Industrial energy efficiency: A policy perspective

    International Nuclear Information System (INIS)

    Chandler, W.U.

    1990-01-01

    Policies that promote energy efficiency can work; but potential energy savings are unlikely to be realized without effective policy leadership. This article discusses the opportunities in several countries for increasing energy efficiency. Both ''open'' and centrally planned economies could be much more energy efficient. In the United States, for example, the government needs to stimulate energy efficiency. This could be done by sponsoring research to develop new processes, creating favourable financial conditions for investment in efficiency, and making the advantages of energy efficiency technologies better known. International collaboration in sponsoring research and transfer technologies could be of the greatest importance in improving energy efficiency in countries with centrally planned economies, including the Soviet Union, as well as in developing countries. Favourable conditions for achieving both economic development and environmental protection can be created through cooperation on the international level. (author). 24 refs, 4 tabs

  5. State-Level Benefits of Energy Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Tonn, Bruce Edward [ORNL

    2007-02-01

    This report describes benefits attributable to state-level energy efficiency programs. Nationwide, state-level energy efficiency programs have targeted all sectors of the economy and have employed a wide range of methods to promote energy efficiency. Standard residential and industrial programs typically identify between 20 to 30% energy savings in homes and plants, respectively. Over a 20 year period of time, an average state that aggressively pursues even a limited array of energy efficiency programs can potentially reduce total state energy use by as much as 20%. Benefit-cost ratios of effective energy efficiency programs typically exceed 3 to 1 and are much higher when non-energy and macroeconomic benefits are included. Indeed, energy efficiency and associated programs and investments can create significant numbers of new jobs and enhance state tax revenues. Several states have incorporated energy efficiency into their economic development programs. It should also be noted that increasing amounts of venture capital are being invested in the energy sector in general and in specific technologies like solar power in particular. Well-designed energy efficiency programs can be expected to help overcome numerous barriers to the market penetration of energy efficient technologies and accelerate the market penetration of the technologies.

  6. State-level benefits of energy efficiency

    International Nuclear Information System (INIS)

    Tonn, Bruce; Peretz, Jean H.

    2007-01-01

    This paper describes benefits attributable to state-level energy efficiency programs. Nationwide, state-level energy efficiency programs have targeted all sectors of the economy and have employed a wide range of methods to promote energy efficiency. Standard residential and industrial programs typically identify between 20% and 30% energy savings in homes and plants, respectively. Over a 20-year period of time, an average state that aggressively pursues even a limited array of energy efficiency programs can potentially reduce total state energy use by as much as 20%. Well-designed energy efficiency programs can be expected to help overcome numerous barriers to the market penetration of energy efficient technologies and accelerate the market penetration of the technologies. Energy efficiency programs are cost-effective; typical benefit-cost ratios exceed 3:1 and are much higher when non-energy and macroeconomic benefits are included. Indeed, energy efficiency and associated programs and investments can create significant numbers of new jobs and enhance state tax revenues. Several states have incorporated energy efficiency into their economic development programs. It should also be noted that increasing amounts of venture capital are being invested in the energy sector in general and in specific technologies like solar power in particular. (author)

  7. Measuring energy efficiency: Is energy intensity a good evidence base?

    International Nuclear Information System (INIS)

    Proskuryakova, L.; Kovalev, A.

    2015-01-01

    Highlights: • Energy intensity measure reflects consumption, not energy efficiency. • Thermodynamic indicators should describe energy efficiency at all levels. • These indicators should have no reference to economic or financial parameters. • A set of energy efficiency indicators should satisfy several basic principles. • There are trade-offs between energy efficiency, power and costs. - Abstract: There is a widespread assumption in energy statistics and econometrics that energy intensity and energy efficiency are equivalent measures of energy performance of economies. The paper points to the discrepancy between the engineering concept of energy efficiency and the energy intensity as it is understood in macroeconomic statistics. This double discrepancy concerns definitions (while engineering concept of energy efficiency is based on the thermodynamic definition, energy intensity includes economic measures) and use. With regard to the latter, the authors conclude that energy intensity can only provide indirect and delayed evidence of technological and engineering energy efficiency of energy conversion processes, which entails shortcomings for management and policymaking. Therefore, we suggest to stop considering subsectoral, sectoral and other levels of energy intensities as aggregates of lower-level energy efficiency. It is suggested that the insufficiency of energy intensity indicators can be compensated with the introduction of thermodynamic indicators describing energy efficiency at the physical, technological, enterprise, sub-sector, sectoral and national levels without references to any economic or financial parameters. Structured statistical data on thermodynamic efficiency is offered as a better option for identifying break-through technologies and technological bottle-necks that constrain efficiency advancements. It is also suggested that macro-level thermodynamic indicators should be based on the thermodynamic first law efficiency and the energy

  8. Energy efficiency of mobile soft robots.

    Science.gov (United States)

    Shui, Langquan; Zhu, Liangliang; Yang, Zhe; Liu, Yilun; Chen, Xi

    2017-11-15

    The performance of mobile soft robots is usually characterized by their locomotion/velocity efficiency, whereas the energy efficiency is a more intrinsic and fundamental criterion for the performance evaluation of independent or integrated soft robots. In this work, a general framework is established to evaluate the energy efficiency of mobile soft robots by considering the efficiency of the energy source, actuator and locomotion, and some insights for improving the efficiency of soft robotic systems are presented. Proposed as the ratio of the desired locomotion kinetic energy to the input mechanical energy, the energy efficiency of locomotion is found to play a critical role in determining the overall energy efficiency of soft robots. Four key factors related to the locomotion energy efficiency are identified, that is, the locomotion modes, material properties, geometric sizes, and actuation states. It is found that the energy efficiency of most mobile soft robots reported in the literature is surprisingly low (mostly below 0.1%), due to the inefficient mechanical energy that essentially does not contribute to the desired locomotion. A comparison of the locomotion energy efficiency for several representative locomotion modes in the literature is presented, showing a descending ranking as: jumping ≫ fish-like swimming > snake-like slithering > rolling > rising/turning over > inchworm-like inching > quadruped gait > earthworm-like squirming. Besides, considering the same locomotion mode, soft robots with lower stiffness, higher density and larger size tend to have higher locomotion energy efficiency. Moreover, a periodic pulse actuation instead of a continuous actuation mode may significantly reduce the input mechanical energy, thus improving the locomotion energy efficiency, especially when the pulse actuation matches the resonant states of the soft robots. The results presented herein indicate a large and necessary space for improving the locomotion energy

  9. Radon and energy efficient homes

    International Nuclear Information System (INIS)

    Burkart, W.

    1981-09-01

    Radon and its daughters in indoor air are presently responsible for dose equivalents of about 31 mSv/year (3 rem/year) to parts of the respiratory tract. Linear extrapolation from the dose response values of uranium miners heavily exposed to radon and its decay products would suggest that almost all lung cancers in the non-smoking population are caused by environmental 222 Rn. Using epidemiological data on the types of lung cancer found in non-smokers of the general public as compared to the miners, a smaller effect of low level radon exposure is assumed, which would result in a lung cancer mortality rate due to radon of about 10 deaths per year and million or 25% of the non-smoker rate. Higher indoor radon concentrations in energy efficient homes mostly caused by reduced air exchange rates will lead to a several fold increase of the lung cancer incidence from radon. Based on the above assumption, about 100 additional lung cancer deaths/year-million will result both from an increase in radionuclide concentrations in indoor air and a concomitant rise in effectiveness of radiation to cause cancer with higher exposure levels. Possibilities to reduce indoor radon levels in existing buildings and costs involved are discussed. (Auth.)

  10. Promoting energy efficiency in Egyptian industry

    International Nuclear Information System (INIS)

    Selim, M.H.

    1990-01-01

    The energy situation in Egypt is characterized by a rather high energy demand, a high annual increase in energy consumption, inefficient utilization of energy, and heavily subsidized energy prices. Energy efficiency is therefore considered to be a matter of top priority, as it would lead to substantial savings. A national policy for efficient use of energy in industry has been outlined, including the establishment of an Industrial Energy Conservation Centre (IECC), the training and upgrading of energy management specialists, and the introduction of energy efficiency technologies in industrial plants. In this article the assistance that international organizations and donors can give to energy efficiency programmes is demonstrated. The results obtained so far are discussed and the lessons, findings and experience gained are outlined. (author). 1 tab

  11. 75 FR 69655 - Energy Efficiency and Renewable Energy Advisory Committee (ERAC)

    Science.gov (United States)

    2010-11-15

    ... DEPARTMENT OF ENERGY Office of Energy Efficiency and Renewable Energy Energy Efficiency and Renewable Energy Advisory Committee (ERAC) AGENCY: Department of Energy, Office of Energy Efficiency and... Energy Efficiency and Renewable Energy Advisory [[Page 69656

  12. Research opportunities in salt hydrates for thermal energy storage

    Science.gov (United States)

    Braunstein, J.

    1983-11-01

    The state of the art of salt hydrates as phase change materials for low temperature thermal energy storage is reviewed. Phase equilibria, nucleation behavior and melting kinetics of the commonly used hydrate are summarized. The development of efficient, reliable inexpensive systems based on phase change materials, especially salt hydrates for the storage (and retrieval) of thermal energy for residential heating is outlined. The use of phase change material thermal energy storage systems is not yet widespread. Additional basic research is needed in the areas of crystallization and melting kinetics, prediction of phase behavior in ternary systems, thermal diffusion in salt hydrate systems, and in the physical properties pertinent to nonequilibrium and equilibrium transformations in these systems.

  13. Efficiency improvement of thermal coal power plants

    Energy Technology Data Exchange (ETDEWEB)

    Hourfar, D. [VEBA Kraftwerke Ruhr Ag, Gelsenkirchen (Germany)

    1996-12-31

    The discussion concerning an increase of the natural greenhouse effect by anthropogenic changes in the composition of the atmosphere has increased over the past years. The greenhouse effect has become an issue of worldwide debate. Carbon dioxide is the most serious emission of the greenhouse gases. Fossil-fired power plants have in the recent past been responsible for almost 30 % of the total CO{sub 2} emissions in Germany. Against this background the paper will describe the present development of CO{sub 2} emissions from power stations and present actual and future opportunities for CO{sub 2} reduction. The significance attached to hard coal as one of today`s prime sources of energy with the largest reserves worldwide, and, consequently, its importance for use in power generation, is certain to increase in the years to come. The further development of conventional power plant technology, therefore, is vital, and must be carried out on the basis of proven operational experience. The main incentive behind the development work completed so far has been, and continues to be, the achievement of cost reductions and environmental benefits in the generation of electricity by increasing plant efficiency, and this means that, in both the short and the long term, power plants with improved conventional technology will be used for environmentally acceptable coal-fired power generation.

  14. Thermal Comfort and Strategies for Energy Conservation.

    Science.gov (United States)

    Rohles, Frederick H., Jr.

    1981-01-01

    Discusses studies in thermal comfort which served as the basis for the comfort standard. Examines seven variables in the human response to the thermal environment in terms of the ways in which they can be modified to conserve energy. (Author/MK)

  15. Energy Efficiency Resources to Support State Energy Planning

    Energy Technology Data Exchange (ETDEWEB)

    Office of Strategic Programs, Strategic Priorities and Impact Analysis Team

    2017-06-01

    An early step for most energy efficiency planning is to identify and quantify energy savings opportunities, and then to understand how to access this potential. The U.S. Department of Energy’s Office of Energy Efficiency and Renewable Energy offers resources that can help with both of these steps. This fact sheet presents those resources. The resources are also available on the DOE State and Local Solution Center on the "Energy Efficiency: Savings Opportunities and Benefits" page: https://energy.gov/eere/slsc/energy-efficiency-savings-opportunities-and-benefits.

  16. Advances in solar thermal energy in Uruguay

    International Nuclear Information System (INIS)

    Franco Noceto, P.

    2012-01-01

    This article is about the law 18585 which declared de solar thermal energy as national interest. This law establishes the obligation to incorporate solar heating systems in health care centers, hotels and sports clubs.

  17. An Improved Flexible Solar Thermal Energy Integration Process for Enhancing the Coal-Based Energy Efficiency and NOx Removal Effectiveness in Coal-Fired Power Plants under Different Load Conditions

    Directory of Open Access Journals (Sweden)

    Yu Han

    2017-09-01

    Full Text Available An improved flexible solar-aided power generation system (SAPG for enhancing both selective catalytic reduction (SCR de-NOx efficiency and coal-based energy efficiency of coal-fired power plants is proposed. In the proposed concept, the solar energy injection point is changed for different power plant loads, bringing about different benefits for coal-fired power generation. For partial/low load, solar energy is beneficially used to increase the flue gas temperature to guarantee the SCR de-NOx effectiveness as well as increase the boiler energy input by reheating the combustion air. For high power load, solar energy is used for saving steam bleeds from turbines by heating the feed water. A case study for a typical 1000 MW coal-fired power plant using the proposed concept has been performed and the results showed that, the SCR de-NOx efficiency of proposed SAPG could increase by 3.1% and 7.9% under medium load and low load conditions, respectively, as compared with the reference plant. The standard coal consumption rate of the proposed SAPG could decrease by 2.68 g/kWh, 4.05 g/kWh and 6.31 g/kWh for high, medium and low loads, respectively, with 0.040 USD/kWh of solar generated electricity cost. The proposed concept opens up a novel solar energy integration pattern in coal-fired power plants to improve the pollutant removal effectiveness and decrease the coal consumption of the power plant.

  18. Energy efficiency in industry and transportation

    International Nuclear Information System (INIS)

    Ruscoe, J.

    1990-01-01

    The discussion of energy issues has changed since the 1970s as improvements have been made in energy efficiency. The present capacity for surplus energy production in economically advanced countries reflects a decrease in energy requirements as well as new production sources. At the same time, the energy crisis can be seen as having discouraged improvements in energy efficiency because of its negative impact on growth. And the centrally planned economies remain highly inefficient energy users. Economic growth encourages the use of new technologies which are likely to be less energy-intensive than those they replace. Permanent gains in energy efficiency are derived from structural changes in the economy and from the introduction of energy-efficient technologies. This article addresses the prospect of increased energy conservation, particularly in industry (the end-use which consumes the most energy) and transportation. Although investments in projects to promote energy conservation are more cost-effective and environment-friendly than investments in energy supply, there is still widespread support for the latter. Developing countries naturally give preference to quantitative growth, with an increasing consumption of energy, but in these countries, too, more efficient use of energy could greatly reduce demand. The policies of international development agencies which still favour increasing energy supply over conservation need to change. Awareness of the need to reduce energy demand is, however, growing worldwide. (author)

  19. Development of Energy Efficiency Indicators in Russia

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    Russia is sometimes referred to as 'the Saudi Arabia of energy efficiency'; its vast potential to reduce energy consumption can be considered a significant 'energy reserve'. Russia, recognising the benefits of more efficient use of energy, is taking measures to exploit this potential. The president has set the goal to reduce energy intensity by 40% between 2007 and 2020. In the past few years, the IEA has worked closely with Russian authorities to support the development of energy efficiency indicators in Russia, critical to an effective implementation and monitoring of Russia's ambitious energy intensity and efficiency goals. The key findings of the IEA work with Russia on developing energy efficiency indicators form the core of this report.

  20. Benefits for whom? Energy efficiency within the efficient market

    International Nuclear Information System (INIS)

    Chello, Dario

    2015-01-01

    How should the lack of an efficient energy market affect the design of energy efficiency policies and their implementation? What the consequences of an inefficient energy market on end users’ behaviour? This article tries to give an answer to such questions, by considering the decision making of domestic users following a few fundamental concepts of behavioural economics. The mechanism of price formation in the market, with particular reference to the internal energy market in Europe, will be examined and we will show that price remains the inflexible attribute in making an energy choice. Then, some conclusions will be addressed to policy makers on how to overcome the barriers illustrated.

  1. Energy and exergy analyses of an ice-on-coil thermal energy storage system

    International Nuclear Information System (INIS)

    Ezan, Mehmet Akif; Erek, Aytunç; Dincer, Ibrahim

    2011-01-01

    In this study, energy and exergy analyses are carried out for the charging period of an ice-on-coil thermal energy storage system. The present model is developed using a thermal resistance network technique. First, the time-dependent variations of the predicted total stored energy, mass of ice, and outlet temperature of the heat transfer fluid from a storage tank are compared with the experimental data. Afterward, performance of an ice-on-coil type latent heat thermal energy storage system is investigated for several working and design parameters. The results of a comparative study are presented in terms of the variations of the heat transfer rate, total stored energy, dimensionless energetic/exergetic effectiveness and energy/exergy efficiency. The results indicate that working and design parameters of the ice-on-coil thermal storage tank should be determined by considering both energetic and exergetic behavior of the system. For the current parameters, storage capacity and energy efficiency of the system increases with decreasing the inlet temperature of the heat transfer fluid and increasing the length of the tube. Besides, the exergy efficiency increases with increasing the inlet temperature of the heat transfer fluid and increasing the length of the tube. -- Highlights: ► A comprehensive study on energy and exergy analyses of an ice-on-coil TES system. ► Determination of irreversibilities and their potential sources. ► Evaluation of both energy and exergy efficiencies and their comparisons.

  2. Promotion of energy efficiency in enterprises

    International Nuclear Information System (INIS)

    Beltrani, G.; Schelske, O.; Peter, D.; Oettli, B.

    2003-01-01

    This comprehensive report for the Swiss Federal Office of Energy (SFOE) presents the results of a study made within the framework of the research programme on energy-economics fundamentals on how the energy efficiency of enterprises can be improved. The report first examines the present state of affairs in Swiss enterprises and looks into the interaction of energy efficiency and environmental management systems. ISO 14001 certification is discussed and examples are given of the responses of various enterprises to a survey concerning the role of energy efficiency in environmental management. Both hindrances and success factors for the embedding of energy-efficiency measures in environmental management activities are discussed and examples are given. Instruments available in Switzerland and from abroad that can be used to promote energy efficiency in enterprises are discussed. Four particular instruments are presented; guidelines and computer-based tools that help in the making of energy-relevant investment decisions, incentives to take part in an energy-benchmark system for small and medium-sized enterprises (SME), low-interest loans for investments in energy-efficiency for SMEs and the closer definition of 'continuous improvement' of energy efficiency within the framework of ISO 14001. The results of a survey amongst those involved are discussed. The report is concluded with recommendations for the implementation of the guidelines and for improvements in the integration of energy efficiency in environmental management systems

  3. Recent development in thermally activated desalination methods: achieving an energy efficiency less than 2.5 kWhelec/m3

    KAUST Repository

    Shahzad, Muhammad Wakil; Thu, Kyaw; Ng, Kim Choon; WonGee, Chun

    2015-01-01

    Water-Energy-Environment nexus is a crucial consideration when designing seawater desalination processes, particularly for the water-stressed countries where the annual water availability is less than 250 m3 per capita. Despite the thermodynamics

  4. Novel Magnetic-to-Thermal Conversion and Thermal Energy Management Composite Phase Change Material

    Directory of Open Access Journals (Sweden)

    Xiaoqiao Fan

    2018-05-01

    Full Text Available Superparamagnetic materials have elicited increasing interest due to their high-efficiency magnetothermal conversion. However, it is difficult to effectively manage the magnetothermal energy due to the continuous magnetothermal effect at present. In this study, we designed and synthesized a novel Fe3O4/PEG/SiO2 composite phase change material (PCM that can simultaneously realize magnetic-to-thermal conversion and thermal energy management because of outstanding thermal energy storage ability of PCM. The composite was fabricated by in situ doping of superparamagnetic Fe3O4 nanoclusters through a simple sol–gel method. The synthesized Fe3O4/PEG/SiO2 PCM exhibited good thermal stability, high phase change enthalpy, and excellent shape-stabilized property. This study provides an additional promising route for application of the magnetothermal effect.

  5. Enhancing radiative energy transfer through thermal extraction

    Science.gov (United States)

    Tan, Yixuan; Liu, Baoan; Shen, Sheng; Yu, Zongfu

    2016-06-01

    Thermal radiation plays an increasingly important role in many emerging energy technologies, such as thermophotovoltaics, passive radiative cooling and wearable cooling clothes [1]. One of the fundamental constraints in thermal radiation is the Stefan-Boltzmann law, which limits the maximum power of far-field radiation to P0 = σT4S, where σ is the Boltzmann constant, S and T are the area and the temperature of the emitter, respectively (Fig. 1a). In order to overcome this limit, it has been shown that near-field radiations could have an energy density that is orders of magnitude greater than the Stefan-Boltzmann law [2-7]. Unfortunately, such near-field radiation transfer is spatially confined and cannot carry radiative heat to the far field. Recently, a new concept of thermal extraction was proposed [8] to enhance far-field thermal emission, which, conceptually, operates on a principle similar to oil immersion lenses and light extraction in light-emitting diodes using solid immersion lens to increase light output [62].Thermal extraction allows a blackbody to radiate more energy to the far field than the apparent limit of the Stefan-Boltzmann law without breaking the second law of thermodynamics. Thermal extraction works by using a specially designed thermal extractor to convert and guide the near-field energy to the far field, as shown in Fig. 1b. The same blackbody as shown in Fig. 1a is placed closely below the thermal extractor with a spacing smaller than the thermal wavelength. The near-field coupling transfers radiative energy with a density greater than σT4. The thermal extractor, made from transparent and high-index or structured materials, does not emit or absorb any radiation. It transforms the near-field energy and sends it toward the far field. As a result, the total amount of far-field radiative heat dissipated by the same blackbody is greatly enhanced above SσT4, where S is the area of the emitter. This paper will review the progress in thermal

  6. Energy efficiency practices among road freight hauliers

    International Nuclear Information System (INIS)

    Liimatainen, Heikki; Stenholm, Pekka; Tapio, Petri; McKinnon, Alan

    2012-01-01

    The reduction of greenhouse gases (GHG) is a highly prevalent public policy goal among European Union member countries. In the new White Paper on transport, the role of road freight transports in this is strongly emphasized. This far, however, the efficiency practices utilised in logistics firms are less studied. Drawing from policy goals and new survey data on 295 road transport firms our results show that hauliers are aware of the possible energy efficiency actions but lack the knowledge and resources to fully utilize them. Energy efficiency seems also to be unimportant for many shippers, so there are no incentives for hauliers to improve it. Examples from various countries show that clear energy efficiency improvements can be achieved with active cooperation between hauliers, shippers and policy makers. Such cooperation can be developed in Finland through the sectoral energy efficiency agreements. The novelty and the utility of these results allow scholars to answer important open questions in the national-level determinants of enhancing energy efficiency practices among road freight hauliers, and contribute to our understanding of how these can be fostered in public policies. - Highlights: ► Hauliers still monitor their fuel consumption with unsophisticated methods. ► Larger hauliers are more active in energy efficiency related issues than smaller ones. ► Hauliers are aware of energy efficiency actions, but lack knowledge of implementation. ► Finnish energy efficiency agreement provides a good framework for public policies. ► Companies that monitor and improve energy efficiency may gain competitive advantage.

  7. Industrial Energy Efficiency and Climate Change Mitigation

    Energy Technology Data Exchange (ETDEWEB)

    Worrell, Ernst; Bernstein, Lenny; Roy, Joyashree; Price, Lynn; de la Rue du Can, Stephane; Harnisch, Jochen

    2009-02-02

    Industry contributes directly and indirectly (through consumed electricity) about 37% of the global greenhouse gas emissions, of which over 80% is from energy use. Total energy-related emissions, which were 9.9 GtCO2 in 2004, have grown by 65% since 1971. Even so, industry has almost continuously improved its energy efficiency over the past decades. In the near future, energy efficiency is potentially the most important and cost-effective means for mitigating greenhouse gas emissions from industry. This paper discusses the potential contribution of industrial energy efficiency technologies and policies to reduce energy use and greenhouse gas emissions to 2030.

  8. Speech for the defense of energy efficiency

    International Nuclear Information System (INIS)

    Escande, Ph.; Laforce, M.

    2006-01-01

    This article reprints an interview of C. Mandil, executive director of IEA who comments some of the recent energy policy events: the recent mergers between European energy companies and the competition on energy markets, the role and share of nuclear energy and renewable energies in the energy mix, the Russian gas affair and the energy efficiency in Russia, the oil prices and the Iranian threat of exports disruption, the peak oil and the decay of petroleum production, the energy efficiency in China, the global warming and the Kyoto protocol. (J.S.)

  9. Energy efficiency trends and policy in Slovenia

    International Nuclear Information System (INIS)

    Al-Mansour, Fouad

    2011-01-01

    The energy dependency of Slovenia is high (52.1%), but it is a little lower than the average energy dependency in the EU 27 (53.8%). Slovenia imports all its petroleum products and natural gas and partly coal and electricity. The energy intensity of Slovenia is higher by about 50% than the average in the EU 27. The target of the EU Directive on energy end-use efficiency and energy services adopted in 2006 is to achieve a 9% improvement of EE (energy efficiency) within the period 2008-2016. The new target of the EU climate and energy package '20-20-20 plan' is a 20% increase in EE by 2020. Since 1991 the Slovenian government has been supporting energy efficiency activities. The improvement of EE was one of the targets of strategic energy documents ReSROE (Resolution on the Strategy of Use and Supply of Energy in Slovenia from 1996 and ReNEP (Resolution on the National Energy Programme) from 2004 adopted by the Slovenian National Assembly (Parliament) in previous years. The Energy Act adopted in 1999 defines the objective of energy policy as giving priority to EE and utilization of renewable energy sources. The goals of the 'National Energy Action Plan 2008-2016 (NEEAP)' adopted by the Slovenian government in 2008 include a set of energy efficiency improvement instruments in the residential, industrial, transport and tertiary sectors. The target of the NEEAP is to save final energy in the 2008-2016 period, amounting to at least 4261 GWh or 9% of baseline consumption. The indicators of energy efficiency trends show considerable improvement in the period from 1998 to 2007. The improvement of EE was reached in all sectors: manufacturing, transport and households. The paper analyses the structure, trends of energy consumption and energy efficiency indicators by sectors of economic activity. A review of energy efficiency policy and measures is described in the paper.

  10. Graphene Thermal Properties: Applications in Thermal Management and Energy Storage

    Directory of Open Access Journals (Sweden)

    Jackie D. Renteria

    2014-11-01

    Full Text Available We review the thermal properties of graphene, few-layer graphene and graphene nanoribbons, and discuss practical applications of graphene in thermal management and energy storage. The first part of the review describes the state-of-the-art in the graphene thermal field focusing on recently reported experimental and theoretical data for heat conduction in graphene and graphene nanoribbons. The effects of the sample size, shape, quality, strain distribution, isotope composition, and point-defect concentration are included in the summary. The second part of the review outlines thermal properties of graphene-enhanced phase change materials used in energy storage. It is shown that the use of liquid-phase-exfoliated graphene as filler material in phase change materials is promising for thermal management of high-power-density battery parks. The reported experimental and modeling results indicate that graphene has the potential to outperform metal nanoparticles, carbon nanotubes, and other carbon allotropes as filler in thermal management materials.

  11. Energy efficiency rating of districts, case Finland

    International Nuclear Information System (INIS)

    Hedman, Åsa; Sepponen, Mari; Virtanen, Mikko

    2014-01-01

    There is an increasing political pressure on the city planning to create more energy efficient city plans. Not only do the city plans have to enable and promote energy efficient solutions, but it also needs to be clearly assessed how energy efficient the plans are. City planners often have no or poor know how about energy efficiency and building technologies which makes it difficult for them to answer to this need without new guidelines and tools. An easy to use tool for the assessment of the energy efficiency of detailed city plans was developed. The aim of the tool is for city planners to easily be able to assess the energy efficiency of the proposed detailed city plan and to be able to compare the impacts of changes in the plan. The tool is designed to be used with no in-depth knowledge about energy or building technology. With a wide use of the tool many missed opportunities for improving energy efficiency can be avoided. It will provide better opportunities for sustainable solutions leading to less harmful environmental impact and reduced emissions. - Highlights: • We have created a tool for assessing energy efficiency of detailed city plans. • The energy source is the most important factor for efficiency of districts in Finland. • Five case districts in Finland were analyzed. • In this paper one residential district has in-depth sensitivity analyses done

  12. Quantum efficiency and thermal emittance of metal photocathodes

    Directory of Open Access Journals (Sweden)

    David H. Dowell

    2009-07-01

    Full Text Available Modern electron beams have demonstrated the brilliance needed to drive free electron lasers at x-ray wavelengths with major advances occurring since the invention of the photocathode gun and the realization of emittance compensation. These state-of-the-art electron beams are now becoming limited by the intrinsic thermal emittance of the cathode. In both dc and rf photocathode guns details of the cathode emission physics strongly influence the quantum efficiency and the thermal emittance. Therefore improving cathode performance is essential to increasing the brightness of beams. It is especially important to understand the fundamentals of cathode quantum efficiency and thermal emittance. This paper investigates the relationship between the quantum efficiency and the thermal emittance for metal cathodes using the Fermi-Dirac model for the electron distribution. We use a consistent theory to derive the quantum efficiency and thermal emittance, and compare our results to those of others.

  13. The Quantum Efficiency and Thermal Emittance of Metal Photocathodes

    International Nuclear Information System (INIS)

    Dowell, D.

    2009-01-01

    Modern electron beams have demonstrated the brilliance needed to drive free electron lasers at x-ray wavelengths, with the principle improvements occurring since the invention of the photocathode gun. The state-of-the-art normalized emittance electron beams are now becoming limited by the thermal emittance of the cathode. In both DC and RF photocathode guns, details of the cathode emission physics strongly influence the quantum efficiency and the thermal emittance. Therefore improving cathode performance is essential to increasing the brightness of beams. It is especially important to understand the fundamentals of cathode quantum efficiency and thermal emittance. This paper investigates the relationship between the quantum efficiency and the thermal emittance of metal cathodes using the Fermi-Dirac model for the electron distribution. We derive the thermal emittance and its relationship to the quantum efficiency, and compare our results to those of others

  14. Transition Towards Energy Efficient Machine Tools

    CERN Document Server

    Zein, André

    2012-01-01

    Energy efficiency represents a cost-effective and immediate strategy of a sustainable development. Due to substantial environmental and economic implications, a strong emphasis is put on the electrical energy requirements of machine tools for metalworking processes. The improvement of energy efficiency is however confronted with diverse barriers, which sustain an energy efficiency gap of unexploited potential. The deficiencies lie in the lack of information about the actual energy requirements of machine tools, a minimum energy reference to quantify improvement potential and the possible actions to improve the energy demand. Therefore, a comprehensive concept for energy performance management of machine tools is developed which guides the transition towards energy efficient machine tools. It is structured in four innovative concept modules, which are embedded into step-by-step workflow models. The capability of the performance management concept is demonstrated in an automotive manufacturing environment. The ...

  15. Thermal energy storage using phase change materials fundamentals and applications

    CERN Document Server

    Fleischer, Amy S

    2015-01-01

    This book presents a comprehensive introduction to the use of solid‐liquid phase change materials to store significant amounts of energy in the latent heat of fusion. The proper selection of materials for different applications is covered in detail, as is the use of high conductivity additives to enhance thermal diffusivity. Dr. Fleischer explores how applications of PCMS have expanded over the past 10 years to include the development of high efficiency building materials to reduce heating and cooling needs, smart material design for clothing, portable electronic systems thermal management, solar thermal power plant design and many others. Additional future research directions and challenges are also discussed.

  16. Promotion of Efficient Use of Energy

    Energy Technology Data Exchange (ETDEWEB)

    Harry Misuriello; DOE Project Officer - Keith Bennett

    2006-01-25

    The Department of Energy funded the Alliance to Save Energy to promote the efficient use of energy under a multiyear cooperative agreement. This funding allowed the Alliance to be innovative and flexible in its program development, and to initiate and enhance projects it would otherwise not have been able to pursue. The program period was 1999 through 2004. The mission of the Alliance to Save Energy is to promote energy efficiency domestically and worldwide. The Alliance followed this mission by working closely with consumers, government, policy makers, and energy efficient product and service providers. The projects that were initiated by the Alliance included communication and consumer education, policy analysis and research, the promotion of interaction among the energy efficiency industry, and international energy efficiency programs. The funding from the Department of Energy allowed the Alliance to study new issues in energy efficiency, draw public attention to those issues, and create targeted programs, such as the Efficient Windows Collaborative or the Green Schools program, which now function on their own to promote energy efficiency in important areas.

  17. Energy efficient heating and ventilation of large halls

    CERN Document Server

    Hojer, Ondrej; Kabele, Karel; Kotrbaty, Miroslav; Sommer, Klaus; Petras, Dusan

    2011-01-01

    This guidebook is focused on modern methods for design, control and operation of energy efficient heating systems in large spaces and industrial halls. The book deals with thermal comfort, light and dark gas radiant heaters, panel radiant heating, floor heating and industrial air heating systems. Various heating systems are illustrated with case studies. Design principles, methods and modeling tools are presented for various systems.

  18. Residential Energy Efficiency Potential: Texas

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-02

    Energy used by Texas single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  19. Residential Energy Efficiency Potential: Oregon

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-02

    Energy used by Oregon single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  20. Residential Energy Efficiency Potential: Pennsylvania

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-02

    Energy used by Pennsylvania single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  1. Residential Energy Efficiency Potential: Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-02

    Energy used by Tennessee single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  2. Residential Energy Efficiency Potential: Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-16

    Energy used by Nevada single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  3. Residential Energy Efficiency Potential: Nebraska

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-22

    Energy used by Nebraska single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  4. Residential Energy Efficiency Potential: Washington

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-27

    Energy used by Washington single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  5. Residential Energy Efficiency Potential: Alabama

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-15

    Energy used by Alabama single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  6. Residential Energy Efficiency Potential: Maryland

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-16

    Energy used by Maryland single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  7. Residential Energy Efficiency Potential: Minnesota

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-22

    Energy used by Minnesota single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  8. Residential Energy Efficiency Potential: Florida

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-16

    Energy used by Florida single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  9. Residential Energy Efficiency Potential: Wisconsin

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-27

    Energy used by Wisconsin single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  10. Residential Energy Efficiency Potential: Maine

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-02

    Energy used by Maine single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  11. Residential Energy Efficiency Potential: Georgia

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-17

    Energy used by Georgia single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  12. Residential Energy Efficiency Potential: Missouri

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-22

    Energy used by Missouri single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  13. Residential Energy Efficiency Potential: Utah

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-22

    Energy used by Utah single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  14. Residential Energy Efficiency Potential: Idaho

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-02

    Energy used by Idaho single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  15. Residential Energy Efficiency Potential: Arizona

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-16

    Energy used by Arizona single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  16. Residential Energy Efficiency Potential: Virginia

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-27

    Energy used by Virginia single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  17. Residential Energy Efficiency Potential: Kentucky

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-02

    Energy used by Kentucky single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  18. Residential Energy Efficiency Potential: Kansas

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-02

    Energy used by Kansas single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  19. Residential Energy Efficiency Potential: Louisiana

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-02

    Energy used by Louisiana single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  20. Residential Energy Efficiency Potential: Iowa

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-02

    Energy used by Iowa single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  1. Residential Energy Efficiency Potential: Wyoming

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-27

    Energy used by Wyoming single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  2. Residential Energy Efficiency Potential: Illinois

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-02

    Energy used by Illinois single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  3. Residential Energy Efficiency Potential: Delaware

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-16

    Energy used by Delaware single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  4. Residential Energy Efficiency Potential: Arkansas

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-16

    Energy used by Arkansas single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  5. Residential Energy Efficiency Potential: Montana

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-22

    Energy used by Montana single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  6. Residential Energy Efficiency Potential: Mississippi

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-22

    Energy used by Mississippi single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  7. Residential Energy Efficiency Potential: Michigan

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-22

    Energy used by Michigan single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  8. Residential Energy Efficiency Potential: Colorado

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-16

    Energy used by Colorado single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  9. Residential Energy Efficiency Potential: Connecticut

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-16

    Energy used by Connecticut single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  10. Residential Energy Efficiency Potential: Indiana

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-02

    Energy used by Indiana single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  11. Residential Energy Efficiency Potential: California

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-16

    Energy used by California single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  12. Residential Energy Efficiency Potential: Vermont

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-22

    Energy used by Vermont single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  13. Residential Energy Efficiency Potential: Massachusetts

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-21

    Energy used by Massachusetts single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  14. Residential Energy Efficiency Potential: Ohio

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-02

    Energy used by Ohio single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  15. Residential Energy Efficiency Potential: Oklahoma

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Eric J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-02

    Energy used by Oklahoma single-family homes that can be saved through cost-effective improvements. Prepared by Eric Wilson and Noel Merket, NREL, and Erin Boyd, U.S. Department of Energy Office of Energy Policy and Systems Analysis.

  16. Regional level approach for increasing energy efficiency

    International Nuclear Information System (INIS)

    Viholainen, Juha; Luoranen, Mika; Väisänen, Sanni; Niskanen, Antti; Horttanainen, Mika; Soukka, Risto

    2016-01-01

    Highlights: • Comprehensive snapshot of regional energy system for decision makers. • Connecting regional sustainability targets and energy planning. • Involving local players in energy planning. - Abstract: Actions for increasing the renewable share in the energy supply and improving both production and end-use energy efficiency are often built into the regional level sustainability targets. Because of this, many local stakeholders such as local governments, energy producers and distributors, industry, and public and private sector operators require information on the current state and development aspects of the regional energy efficiency. The drawback is that an overall view on the focal energy system operators, their energy interests, and future energy service needs in the region is often not available for the stakeholders. To support the local energy planning and management of the regional energy services, an approach for increasing the regional energy efficiency is being introduced. The presented approach can be seen as a solid framework for gathering the required data for energy efficiency analysis and also evaluating the energy system development, planned improvement actions, and the required energy services at the region. This study defines the theoretical structure of the energy efficiency approach and the required steps for revealing such energy system improvement actions that support the regional energy plan. To demonstrate the use of the approach, a case study of a Finnish small-town of Lohja is presented. In the case example, possible actions linked to the regional energy targets were evaluated with energy efficiency analysis. The results of the case example are system specific, but the conducted study can be seen as a justified example of generating easily attainable and transparent information on the impacts of different improvement actions on the regional energy system.

  17. Southwest Energy Efficiency Project (SWEEP) Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Geller, Howard [Southwest Energy Efficiency Project (SWEEP), Boulder, CO (United States); Meyers, Jim [Southwest Energy Efficiency Project (SWEEP), Boulder, CO (United States)

    2018-01-29

    SWEEP worked with Energy Efficiency and Renewable Energy (EERE) programs to foster greater energy efficiency throughout the Southwest. SWEEP accomplished this through a combination of analysis and support; preparation and distribution of materials on best practice technologies, policies and programs; and technical assistance and information dissemination to states and municipalities in the southwest supporting BTO, AMO, OWIP for advancement of efficiency in products and practices. These efforts were accomplished during the period 2012 through 2017.

  18. Energy efficiency, market failures, and government policy

    International Nuclear Information System (INIS)

    Levine, M.D.; Koomey, J.G.; McMahon, J.E.; Sanstad, A.H.; Hirst, E.

    1994-03-01

    This paper presents a framework for evaluating engineering-economic evidence on the diffusion of energy efficiency improvements. Four examples are evaluated within this framework. The analysis provides evidence of market failures related to energy efficiency. Specific market failures that may impede the adoption of cost-effective energy efficiency are discussed. Two programs that have had a major impact in overcoming these market failures, utility DSM programs and appliance standards, are described

  19. Energy Efficiency in Norway 1990-2000

    Energy Technology Data Exchange (ETDEWEB)

    Rosenberg, Eva

    2003-06-01

    This is the national report for Norway in the EU/SAVE project ''Indicators for Energy Efficiency Monitoring and Target setting (ODYSSEE)''. The report deals with energy use and energy efficiency in Norway 1990-2000 (2001 for overall energy use). Final energy use per Gross Domestic Product (GDP) was reduced by approximately 1.9% pr year in the period 1990 to 2001. The energy efficiency improvement has been calculated to 0.6% pr year, while the role of structural changes has been 1.3% pr year. A detailed sector analysis has been done, applying Laspeyres indices to attribute changes in energy use to activity, structure or intensity (efficiency). Aggregating sectors, we have found a total efficiency improvement of approximately 11 TWh from 1990 to 2000. (author)

  20. Indicators for industrial energy efficiency in India

    International Nuclear Information System (INIS)

    Gielen, Dolf; Taylor, Peter

    2009-01-01

    India accounts for 4.5% of industrial energy use worldwide. This share is projected to increase as the economy expands rapidly. The level of industrial energy efficiency in India varies widely. Certain sectors, such as cement, are relatively efficient, while others, such as pulp and paper, are relatively inefficient. Future energy efficiency efforts should focus on direct reduced iron, pulp and paper and small-scale cement kilns because the potentials for improvement are important in both percentage and absolute terms. Under business as usual, industrial energy use is projected to rise faster than total final energy use. A strong focus on energy efficiency can reduce this growth, but CO 2 emissions will still rise substantially. If more substantial CO 2 emissions reductions are to be achieved then energy efficiency will need to be combined with measures that reduce the carbon intensity of the industrial fuel mix.

  1. Investing in Energy Efficiency. Removing the Barriers

    International Nuclear Information System (INIS)

    2004-01-01

    Investing in improving energy efficiency has the clear advantages of reducing energy costs, improving security of supply and mitigating the environmental impacts of energy use. And still, many viable opportunities for higher energy efficiency are not tapped because of the existence of numerous barriers to such investments. These lost opportunities imply costs to the individual energy consumers and to the society as a whole and they are particularly important in economies in transition. This report identifies various types of barriers for making energy efficiency investments (be they of legal, administrative, institutional or financial nature), mainly in buildings, district heating and efficient lighting. The role of various bodies and organisations for the facilitation of energy efficiency investments is analysed, from public authorities and regulators to banks and international financing institutions

  2. DTU International Energy Report 2012: Energy efficiency improvements

    DEFF Research Database (Denmark)

    Increased energy efficiency can reduce global CO2 emissions over the period to 2050 with up to 25%. On the top of that large profits can be gained for very little investment. Energy efficiency improvements can save investment in new energy infrastructure, cut fuel costs, increase competitiveness...... and increase consumer welfare. Thus, it is natural for DTU International Energy Report 2012 to take up this issue and analyze the global, regional and national challenges in exploiting energy efficiency and promote research and development in energy efficiency....

  3. Novel thermal efficiency-based model for determination of thermal conductivity of membrane distillation membranes

    International Nuclear Information System (INIS)

    Vanneste, Johan; Bush, John A.; Hickenbottom, Kerri L.; Marks, Christopher A.; Jassby, David

    2017-01-01

    Development and selection of membranes for membrane distillation (MD) could be accelerated if all performance-determining characteristics of the membrane could be obtained during MD operation without the need to recur to specialized or cumbersome porosity or thermal conductivity measurement techniques. By redefining the thermal efficiency, the Schofield method could be adapted to describe the flux without prior knowledge of membrane porosity, thickness, or thermal conductivity. A total of 17 commercially available membranes were analyzed in terms of flux and thermal efficiency to assess their suitability for application in MD. The thermal-efficiency based model described the flux with an average %RMSE of 4.5%, which was in the same range as the standard deviation on the measured flux. The redefinition of the thermal efficiency also enabled MD to be used as a novel thermal conductivity measurement device for thin porous hydrophobic films that cannot be measured with the conventional laser flash diffusivity technique.

  4. Monitoring tools for energy efficiency in Europe

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    This document brings together the different definitions of the indicators used in the European Odyssee project on energy efficiency indicators. This project was initiated in 1990. It benefits from the combined support of the SAVE programme of the European Commission, of Ademe and of 15 national Efficiency Agencies within the European network of energy efficiency agencies. The objective of the project is to develop and maintain indicators that enable to review progress in energy efficiency and CO{sub 2} emissions abatement, by sector, end-use, etc.. for each country and the EU as a whole. To reach this objective, all data and indicators are stored in a common database called ODYSSEE that is regularly updated. A common methodology is used to produce comparative energy efficiency indicators from the database. The definitions presented in this document concern: 1) the general points (energy intensity, consumption, savings, efficiency, the unit consumption effect and index, the technological effect or savings, the substitution effect and the behavioural/management effect); 2) the macro-indicators (primary and final energy intensities at constant structure, at purchasing power parities, at reference economic structure); 3) industry (energy intensity of industry/manufacturing, of industry at constant structure and at reference structure, unit consumption of steel, cement etc.., process effect); 4) transports (energy intensity, unit consumption of vehicles, average specific consumption, test specific consumption, unit consumption, specific consumption, behavioural energy savings; 5) households and services (unit consumption, specific consumption, energy intensity of households, appliances); 6) transformations (apparent efficiency of energy sector or transformations, efficiency at constant fuel mix, efficiency of electricity sector). The same work is made for the 'key energy efficiency indicators', for the 'aggregate energy efficiency indicators' for

  5. Efficiency assessment and benchmarking of thermal power plants in India

    International Nuclear Information System (INIS)

    Shrivastava, Naveen; Sharma, Seema; Chauhan, Kavita

    2012-01-01

    Per capita consumption of electricity in India is many folds lesser than Canada, USA, Australia, Japan, Chaina and world average. Even though, total energy shortage and peaking shortage were recorded as 11.2% and 11.85%, respectively, in 2008–09 reflecting non-availability of sufficient supply of electricity. Performance improvement of very small amount can lead to large contribution in financial terms, which can be utilized for capacity addition to reduce demand supply gap. Coal fired thermal power plants are main sources of electricity in India. In this paper, relative technical efficiency of 60 coal fired power plants has been evaluated and compared using CCR and BCC models of data envelopment analysis. Target benchmark of input variables has also been evaluated. Performance comparison includes small versus medium versus large power plants and also state owned versus central owned versus private owned. Result indicates poor performance of few power plants due to over use of input resources. Finding reveals that efficiency of small power plants is lower in comparison to medium and large category and also performance of state owned power plants is comparatively lower than central and privately owned. Study also suggests different measures to improve technical efficiency of the plants. - Highlights: ► This study evaluates relative technical efficiency of 60 coal fired thermal power plants of India. ► Input oriented CCR and BCC models of data envelopment analysis have been used. ► Small, medium and large power plants have been compared. ► Study will help investor while setting up new power projects. ► Power plants of different ownerships have also been compared.

  6. National Action Plan for Energy Efficiency Report

    Energy Technology Data Exchange (ETDEWEB)

    National Action Plan for Energy Efficiency

    2006-07-01

    Summarizes recommendations, key barriers, and methods for energy efficiency in utility ratemaking as well as revenue requirements, resource planning processes, rate design, and program best practices.

  7. Transition towards energy efficient machine tools

    Energy Technology Data Exchange (ETDEWEB)

    Zein, Andre [Technische Univ. Braunschweig (Germany). Inst. fuer Werkzeugmaschinen und Fertigungstechnik

    2012-07-01

    Provides unique data about industrial trends affecting the energy demand of machine tools. Presents a comprehensive methodology to assess the energy efficiency of machining processes. Contains an integrated management concept to implement energy performance measures into existing industrial systems. Includes an industrial case study with two exemplary applications. Energy efficiency represents a cost-effective and immediate strategy of a sustainable development. Due to substantial environmental and economic implications, a strong emphasis is put on the electrical energy requirements of machine tools for metalworking processes. The improvement of energy efficiency is however confronted with diverse barriers, which sustain an energy efficiency gap of unexploited potential. The deficiencies lie in the lack of information about the actual energy requirements of machine tools, a minimum energy reference to quantify improvement potential and the possible actions to improve the energy demand. Therefore, a comprehensive concept for energy performance management of machine tools is developed which guides the transition towards energy efficient machine tools. It is structured in four innovative concept modules, which are embedded into step-by-step workflow models. The capability of the performance management concept is demonstrated in an automotive manufacturing environment. The target audience primarily comprises researchers and practitioners challenged to enhance energy efficiency in manufacturing. The book may also be beneficial for graduate students who want to specialize in this field.

  8. Energy efficient technologies for the mining industry

    Energy Technology Data Exchange (ETDEWEB)

    Klein, B.; Bamber, A.; Weatherwax, T.; Dozdiak, J.; Nadolski, S.; Roufail, R.; Parry, J.; Roufail, R.; Tong, L.; Hall, R. [British Columbia Univ., Vancouver, BC (Canada). Centre for Environmental Research in Minerals, Metals and Materials, Norman B. Keevil Inst. of Mining Engineering

    2010-07-01

    Mining in British Columbia is the second largest industrial electricity consumer. This presentation highlighted methods to help the mining industry reduce their energy requirements by limiting waste and improving efficiency. The measures are aimed at optimizing energy-use and efficiency in mining and processing and identifying opportunities and methods of improving this efficiency. Energy conservation in comminution and beneficiation is a primary focus of research activities at the University of British Columbia (UBC). The objective is to reduce energy usage in metal mines by 20 per cent overall. Open pit copper, gold and molybdenum mines are being targeted. Projects underway at UBC were outlined, with particular reference to energy usage, recovery and alternative energy sources; preconcentration; reducing energy usage from comminution in sorting, high pressure grinding rolls and high speed stirred mills; Hydromet; other energy efficient technologies such as control and flotation; and carbon dioxide sequestration. Studies were conducted at various mining facilities, including mines in Sudbury, Ontario. tabs., figs.

  9. Enhancing Low-Grade Thermal Energy Recovery in a Thermally Regenerative Ammonia Battery Using Elevated Temperatures

    KAUST Repository

    Zhang, Fang

    2015-02-13

    © 2015 WILEY-VCH Verlag GmbH & Co. KGaA. A thermally regenerative ammonia battery (TRAB) is a new approach for converting low-grade thermal energy into electricity by using an ammonia electrolyte and copper electrodes. TRAB operation at 72°C produced a power density of 236±8 Wm-2, with a linear decrease in power to 95±5 Wm-2 at 23°C. The improved power at higher temperatures was due to reduced electrode overpotentials and more favorable thermodynamics for the anode reaction (copper oxidation). The energy density varied with temperature and discharge rates, with a maximum of 650 Whm-3 at a discharge energy efficiency of 54% and a temperature of 37°C. The energy efficiency calculated with chemical process simulation software indicated a Carnot-based efficiency of up to 13% and an overall thermal energy recovery of 0.5%. It should be possible to substantially improve these energy recoveries through optimization of electrolyte concentrations and by using improved ion-selective membranes and energy recovery systems such as heat exchangers.

  10. National energy efficiency study. The Czech Republic

    International Nuclear Information System (INIS)

    Maly, M.; Jakubes, J.; Spitz, J.; Van Wees, M.T.; Uyterlinde, M.A.; Martens, J.W.; Van Oostvoorn, F.; Henelova, V.; Vazac, V.; Zalesak, M.; Marousek, J.; Szomolanyiova, J.; Havlickova, M.; Zeman, J.; Ten Donkelaar, M.; Travnicek, S.; Stejskal, F.; Pribyl, E.; Blokker, L.; Bizek, V.; Velthuijsen, J.W.

    1999-08-01

    Energy efficiency and renewable energy production contribute to the three major goals of the national energy policy of the Czech Republic: overall competitiveness, security of supply; and environmental protection. Therefore, the Czech Government aims to promote these two sustainable options. The National Energy Efficiency Study has developed specific policies for the promotion of end use energy efficiency and renewables. These are described in two Action Plans, and in this report which serves as a background document. It contains detailed information on options and measures, potentials, barriers and policy instruments for energy efficiency and renewables. The main part is a detailed outline for a new energy efficiency and renewable policy, including a listing of actions for implementation. Also, it includes recommendations for financing schemes to overcome the investment constraints in the Czech Republic. Finally, a list of concrete projects is presented to support project identification. In addition, two separate Action Plans have been published: (1) The Energy Efficiency Action Plan focuses on promotion of energy efficiency in end-use (separate document, ECN-C-99-065); and (2) The Renewable Energy Action Plan (separate document, ECN-C-99-064) deals with policy on promotion of renewable energy production. These two policy documents should provide policy makers in the Czech Government with essential information on potentials, targets, the required budget, and recommended policy instruments. The core of the Action Plans is the list of concrete policy actions, ready for implementation

  11. Electrothermal efficiency, temperature and thermal conductivity of ...

    Indian Academy of Sciences (India)

    Different types of DC plasma torches operating at power levels between 2 to 6000 kW [1] ... systems and showed that η was higher for the LPPS system. ..... [8] M I Boulos, P Fauchais and E Pfender, Thermal plasmas fundamentals and ...

  12. Energy technologies and energy efficiency in economic modelling

    DEFF Research Database (Denmark)

    Klinge Jacobsen, Henrik

    1998-01-01

    This paper discusses different approaches to incorporating energy technologies and technological development in energy-economic models. Technological development is a very important issue in long-term energy demand projections and in environmental analyses. Different assumptions on technological ...... of renewable energy and especially wind power will increase the rate of efficiency improvement. A technologically based model in this case indirectly makes the energy efficiency endogenous in the aggregate energy-economy model....... technological development. This paper examines the effect on aggregate energy efficiency of using technological models to describe a number of specific technologies and of incorporating these models in an economic model. Different effects from the technology representation are illustrated. Vintage effects...... illustrates the dependence of average efficiencies and productivity on capacity utilisation rates. In the long run regulation induced by environmental policies are also very important for the improvement of aggregate energy efficiency in the energy supply sector. A Danish policy to increase the share...

  13. Efficient Use of Energy: as a Life Style

    Directory of Open Access Journals (Sweden)

    Omneya Sabry

    2017-06-01

    Full Text Available Since the Early Eighties of the last Century, the Egyptian Government considered Energy Conservation as one of the main pillars of Energy Planning in Egypt, based on the fact that investing in Energy Efficiency is more cost effective than in constructing new Power Plants.Energy Efficiency (EE Programs financed by International Financing Institutions focused at that time, on Energy Audits in Industrial Buildings, Power Plants, Electricity Transmission and in some other Governmental Buildings. Recommendations for Efficient Use of Energy and reducing energy consumption at those entities were implemented by the Use of Efficient Lamps, Improving Power Factor, Waste Heat Recovery, Thermal Insulation, Efficient Firing in Boilers…. Consequently, High Quality Energy Efficient Products were competing in the market with others not having the same advantage.Although the above mentioned EE Programs included Awareness Campaigns for all sectors but the consumption in Residential Sector remained high and increased more and more ,exceeding even the consumption in Industrial Sector specially that the prices of electricity were highly subsidized.For that reason, more awareness campaigns (Lectures, Brochures, Audio and visual advertisement and more incentives were offered by Ministry of Electricity and Renewable Energy (MoERE to consumers in the Residential Sector. Meanwhile, a Program to reduce gradually subsidies on electricity prices started aiming to push consumers to follow energy efficiency instructions and buy efficient appliances especially while they were suffering from electricity cut for about two years.To prepare for Market Transformation to efficient appliances the Government, issued the Standard Specifications and Labeling for Energy Efficient Appliances (lamps, refrigerators, freezers, washing machines, air conditioners, dish washers and others. Meanwhile, these Standards are supported with Accredited Testing Labs in National Entities (NREA

  14. Efficient Energy-Storage Concept

    Science.gov (United States)

    Brantley, L. W. J.; Rupp, C.

    1982-01-01

    Space-platform energy-storage and attitude-stabilization system utilizes variable moment of inertia of two masses attached to ends of retractable cable. System would be brought to its initial operating speed by gravity-gradient pumping. When fully developed, concept could be part of an orbiting solar-energy collection system. Energy would be temporarily stored in system then transmitted to Earth by microwaves or other method.

  15. SSTL based thermal and power efficient RAM design on 28nm FPGA for spacecraft

    DEFF Research Database (Denmark)

    Kalia, Kartik; Pandey, Bishwajeet; Hussain, D. M.A.

    2016-01-01

    In this paper, an approach is made to design a Thermal and Power efficient RAM for that reason we have used DDR4L memory and six different members of SSTL I/Os standards on 28nm technology. Every spacecraft requires most energy efficient electronic system and for that very purpose we have designe...

  16. An interdisciplinary perspective on industrial energy efficiency

    International Nuclear Information System (INIS)

    Palm, Jenny; Thollander, Patrik

    2010-01-01

    This paper combines engineering and social science approaches to enhance our understanding of industrial energy efficiency and broaden our perspective on policy making in Europe. Sustainable development demands new strategies, solutions, and policy-making approaches. Numerous studies of energy efficiency potential state that cost-effective energy efficiency technologies in industry are not always implemented for various reasons, such as lack of information, procedural impediments, and routines not favoring energy efficiency. Another reason for the efficiency gap is the existence of particular values, unsupportive of energy efficiency, in the dominant networks of a branch of trade. Analysis indicates that different sectors of rather closed communities have established their own tacit knowledge, perceived truths, and routines concerning energy efficiency measures. Actors in different industrial sectors highlight different barriers to energy efficiency and why cost-effective energy efficiency measures are not being implemented. The identified barriers can be problematized in relation to the social context to understand their existence and how to resolve them.

  17. A study on electric bicycle energy efficiency

    Directory of Open Access Journals (Sweden)

    Ivan EVTIMOV

    2015-09-01

    Full Text Available The paper presents a construction of an experimental electric bicycle for evaluation of the energy efficiency. The bicycle is equipped with onboard computer which can store the information about motion and energy consumption. The result concerning power, energy consumption, recharging during brake process, etc. are given. Energy consumption for 3 typical city routes is studied.

  18. Energy efficiency buildings program, FY 1980

    Energy Technology Data Exchange (ETDEWEB)

    1981-05-01

    A separate abstract was prepared on research progress in each group at LBL in the energy efficient buildings program. Two separate abstracts were prepared for the Windows and Lighting Program. Abstracts prepared on other programs are: Energy Performance of Buildings; Building Ventilation and Indoor Air Quality Program; DOE-21 Building Energy Analysis; and Building Energy Data Compilation, Analysis, and Demonstration. (MCW)

  19. Energy efficient residential house wall system

    International Nuclear Information System (INIS)

    Aldawi, Fayez; Date, Abhijit; Alam, Firoz; Khan, Iftekhar; Alghamdi, Mohammed

    2013-01-01

    The energy consumption and greenhouse gas emission by the residential housing sector are considered to be one of the largest in economically developed countries. The larger energy consumption and greenhouse gas emission not only put additional pressure on finite fossil fuel resources but also cause global warming and climate change. Additionally, the residential housing sector will be consuming more energy as the house demand and average house floor area are progressively increasing. With currently used residential house wall systems, it is hard to reduce energy consumption for ongoing house space heating and cooling. A smart house wall envelope with optimal thermal masses and insulation materials is vital for reducing our increasing energy consumption. The major aim of this study is to investigate thermal performance and energy saving potential of a new house wall system for variable climate conditions. The thermal performance modelling was carried out using commercially developed software AccuRate ® . The findings indicate that a notable energy savings can be accomplished if a smart house wall system is used. -- Highlights: • Smart house wall system. • Thermal performance modelling and star energy rating. • Energy savings and greenhouse gas reduction

  20. Mathematical modelling of a steam boiler room to research thermal efficiency

    International Nuclear Information System (INIS)

    Bujak, J.

    2008-01-01

    This paper introduces a mathematical model of a boiler room to research its thermal efficiency. The model is regarded as an open thermodynamic system exchanging mass, energy, and heat with the atmosphere. On those grounds, the energy and energy balance were calculated. Here I show several possibilities concerning how this model may be applied. Test results of the coefficient of thermal efficiency were compared to a real object, i.e. a steam boiler room of the Provincial Hospital in Wloclawek (Poland). The tests were carried out for 18 months. The results obtained in the boiler room were used for verification of the mathematical model

  1. Options to improve energy efficiency for educational building

    Science.gov (United States)

    Jahan, Mafruha

    The cost of energy is a major factor that must be considered for educational facility budget planning purpose. The analysis of energy related issues and options can be complex and requires significant time and detailed effort. One way to facilitate the inclusion of energy option planning in facility planning efforts is to utilize a tool that allows for quick appraisal of the facility energy profile. Once such an appraisal is accomplished, it is then possible to rank energy improvement options consistently with other facility needs and requirements. After an energy efficiency option has been determined to have meaningful value in comparison with other facility planning options, it is then possible to utilize the initial appraisal as the basis for an expanded consideration of additional facility and energy use detail using the same analytic system used for the initial appraisal. This thesis has developed a methodology and an associated analytic model to assist in these tasks and thereby improve the energy efficiency of educational facilities. A detailed energy efficiency and analysis tool is described that utilizes specific university building characteristics such as size, architecture, envelop, lighting, occupancy, thermal design which allows reducing the annual energy consumption. Improving the energy efficiency of various aspects of an educational building's energy performance can be complex and can require significant time and experience to make decisions. The approach developed in this thesis initially assesses the energy design for a university building. This initial appraisal is intended to assist administrators in assessing the potential value of energy efficiency options for their particular facility. Subsequently this scoping design can then be extended as another stage of the model by local facility or planning personnel to add more details and engineering aspects to the initial screening model. This approach can assist university planning efforts to

  2. A treatment of thermal efficiency improvement in the Brayton cycle

    International Nuclear Information System (INIS)

    Fujii, Terushige; Akagawa, Koji; Nakanishi, Shigeyasu; Inoue, Kiyoshi; Ishigai, Seikan.

    1982-01-01

    So far, as the working fluid for power-generating plants, mainly water and air (combustion gas) have been used. In this study, in regeneration and isothermal compression processes being considered as the means for the efficiency improvement in Brayton cycle, the investigation of equivalent graphical presentation method with T-S diagrams, the introduction of the new characteristic number expressing the possibility of thermal efficiency improvement by regeneration, and the investigation of the effect of the difference of working fluid on thermal efficiency were carried out. Next, as the cycle approximately realizing isothermal compression process with condensation process, the super-critical pressure cycle with liquid phase compression was rated, and four working fluids, NH 3 , SO 2 , CO 2 and H 2 O were examined as perfect gas and real gas. The advantage of CO 2 regeneration for the thermal efficiency improvement was clarified by using the dimensionless characteristic number. The graphical presentation of effective work, the thermal efficiency improvement by regeneration, the thermal efficiency improvement by making compression process isothermal, the effect on thermal efficiency due to various factors and working fluids, the characteristic number by regeneration, and the application to real working fluids are reported. (Kako, I.)

  3. ECOWAS renewable energy and energy efficiency status report - 2014

    International Nuclear Information System (INIS)

    Auth, Katie; Musolino, Evan; Thomas, Tristram; Adebiyi, Adeola; Reiss, Karin; Semedo, Eder; Williamson, Laura E.; Chawla, Kanika; Diarra, Charles

    2014-01-01

    In recent years, the Economic Community of West African States (ECOWAS), comprising 15 Member States, it has emerged as one of the most active and dynamic regional economic communities on the African continent. Expanding access to modern, reliable, and affordable energy services is a key priority, prompting inter-state cooperation in crucial areas including capacity building, policy development and implementation, and investment. Recognising the critical role that sustainable energy plays in catalysing social, economic, and industrial development across the region, ECOWAS Member States formally inaugurated the ECOWAS Centre for Renewable Energy and Energy Efficiency (ECREEE) in 2010 to 'contribute to the sustainable economic, social and environmental development of West Africa by improving access to modern, reliable and affordable energy services, energy security and reduction of energy related externalities'. Drawing on data from the ECOWAS Observatory for Renewable Energy and Energy Efficiency (ECOWREX) and a network of contributors and researchers across the region, the ECOWAS Renewable Energy and Energy Efficiency Status Report supports ECREEE's efforts to increase the deployment of renewable energy and energy efficiency in West Africa by providing a comprehensive regional review of renewable energy and energy efficiency developments, evolving policy landscapes, market trends and related activities, investments in renewable energy and off-grid energy solutions, and the crucial nexus between energy access and gender

  4. Energy efficiency of high-rise buildings

    Science.gov (United States)

    Zhigulina, Anna Yu.; Ponomarenko, Alla M.

    2018-03-01

    The article is devoted to analysis of tendencies and advanced technologies in the field of energy supply and energy efficiency of tall buildings, to the history of the emergence of the concept of "efficiency" and its current interpretation. Also the article show the difference of evaluation criteria of the leading rating systems LEED and BREEAM. Authors reviewed the latest technologies applied in the construction of energy efficient buildings. Methodological approach to the design of tall buildings taking into account energy efficiency needs to include the primary energy saving; to seek the possibility of production and accumulation of alternative electric energy by converting energy from the sun and wind with the help of special technical devices; the application of regenerative technologies.

  5. Regional and global exergy and energy efficiencies

    Energy Technology Data Exchange (ETDEWEB)

    Nakicenovic, N; Kurz, R [International Inst. for Applied Systems Analysis, Laxenburg (Austria). Environmentally Compatible Energy Strategies (Ecuador) Project; Gilli, P V [Graz Univ. of Technology (Austria)

    1996-03-01

    We present estimates of global energy efficiency by applying second-law (exergy) analysis to regional and global energy balances. We use a uniform analysis of national and regional energy balances and aggregate these balances first for three main economic regions and subsequently into world totals. The procedure involves assessment of energy and exergy efficiencies at each step of energy conversion, from primary exergy to final and useful exergy. Ideally, the analysis should be extended to include actual delivered energy services; unfortunately, data are scarce and only rough estimates can be given for this last stage of energy conversion. The overall result is that the current global primary to useful exergy efficiency is about one-tenth of the theoretical maximum and the service efficiency is even lower. (Author)

  6. Factors influencing energy efficiency investments in existing Swedish residential buildings

    Energy Technology Data Exchange (ETDEWEB)

    Nair, Gireesh; Gustavsson, Leif; Mahapatra, Krushna [Ecotechnology, Mid Sweden University, SE-83125 Oestersund (Sweden)

    2010-06-15

    We used the data from a survey conducted in 2008 of 3,000 owners of detached houses to analyse the factors that influence the adoption of investment measures to improve the energy efficiency of their buildings. For the majority of Swedish homeowners, it was important to reduce their household energy use, and most of them undertook no-cost measures as compared to investment measures. Personal attributes such as income, education, age and contextual factors, including age of the house, thermal discomfort, past investment, and perceived energy cost, influence homeowners' preference for a particular type of energy efficiency measure. The implications for promoting the implementation of energy efficiency investment measures are discussed. (author)

  7. Center for Efficiency in Sustainable Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Abraham, Martin [Youngstown State Univ., OH (United States)

    2016-01-31

    /actuator/controller modules to enhance energy capture and reduce aerodynamic loading and noise by way of virtual aerodynamic shaping. Accomplishments: Task I. Improved Energy Efficiency for Industrial Processes: We organized an energy management training session held on February 22, 2011, which was advertised through a regional manufacturing association to provide wide-ranging notification. Over two dozen companies were represented a the seminar, ranging from heavy manufacturing businesses with $5,000,000 per year energy expenses, to small, light manufacturing facilities. Task 2. Landfill Fuel Cell Power Generation Solid Oxide Fuel Cells (SOFCs) were constructed and evaluated as a means of obtaining electrical energy from landfill gas. Analysis of landfill gas. Attempts at collecting gas samples at the landfill and evaluating them on campus were still unsuccessful. Even a Teflon® sample bag would lose its H2S content. Evaluation of Gas Clean-up We consider this a confirmation of the CO2 effect on the solubility of H2S in water making much less sulfide available for the photocatalyst. It also means that another method should be employed to clean up landfill gas. Nonetheless, composition of impurities in landfill gas was reduced sufficiently to allow successful operation of the test fuel cell. Comparison to a PEM fuel cell system. If a PEMFC were to be operated with landfill gas as the fuel, the gas would have to be treated for sulfur removal, and then processed in a reformer large enough to drive the equilibrium far toward the products, so that negligible CO would flow into the fuel cell. Analysis of a fuel cell running on landfill gas. Using a Gow-Mac gas chromatograph with a thermal conductivity detector, unambiguous determination of CO can be made, at least as a primary constituent Task 3: Task 3 Plasma Controlled Turbine Blades Wind Turbine Selection. After carefully reviewing the various model available in the market the team selected the ARE 110 (2.5kW). The ARE 110 provides a very

  8. Energy saving and energy efficiency concepts for policy making

    NARCIS (Netherlands)

    Oikonomou, V.; Becchis, F.; Steg, L.; Russolillo, D.

    Departing from the concept of rational use of energy, the paper outlines the microeconomics of end-use energy saving as a result of frugality or efficiency measures. Frugality refers to the behaviour that is aimed at energy conservation, and with efficiency we refer to the technical ratio between

  9. Energy saving and energy efficiency concepts for policy making

    NARCIS (Netherlands)

    Oikonomou, V.; Becchis, F.; Steg, L.; Russolillo, D.

    2009-01-01

    Departing from the concept of rational use of energy, the paper outlines the microeconomics of end-use energy saving as a result of frugality or efficiency measures. Frugality refers to the behaviour that is aimed at energy conservation, and with efficiency we refer to the technical ratio between

  10. Phase-Change Thermal Energy Storage

    Science.gov (United States)

    1989-11-01

    The goal of this program is to advance the engineering and scientific understanding of solar thermal technology and to establish the technology base from which private industry can develop solar thermal power production options for introduction into the competitive energy market. Solar thermal technology concentrates the solar flux using tracking mirrors or lenses onto a receiver where the solar energy is absorbed as heat and converted into electricity or incorporated into products as process heat. The two primary solar thermal technologies, central receivers and distributed receivers, employ various point and line-focus optics to concentrate sunlight. Current central receiver systems use fields of heliostats (two-axes tracking mirrors) to focus the sun's radiant energy onto a single, tower-mounted receiver. Point focus concentrators up to 17 meters in diameter track the sun in two axes and use parabolic dish mirrors or Fresnel lenses to focus radiant energy onto a receiver. Troughs and bowls are line-focus tracking reflectors that concentrate sunlight onto receiver tubes along their focal lines. Concentrating collector modules can be used alone or in a multimodule system. The concentrated radiant energy absorbed by the solar thermal receiver is transported to the conversion process by a circulating working fluid. Receiver temperatures range from 100 C in low-temperature troughs to over 1500 C in dish and central receiver systems.

  11. Energy Efficiency Policy and Carbon Pricing

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    The main message of this paper is that while carbon pricing is a prerequisite for least-cost carbon mitigation strategies, carbon pricing is not enough to overcome all the barriers to cost-effective energy efficiency actions. Energy efficiency policy should be designed carefully for each sector to ensure optimal outcomes for a combination of economic, social and climate change goals. This paper aims to examine the justification for specific energy efficiency policies in economies with carbon pricing in place. The paper begins with an inventory of existing market failures that attempt to explain the limited uptake of energy efficiency. These market failures are investigated to see which can be overcome by carbon pricing in two subsectors -- electricity use in residential appliances and heating energy use in buildings. This analysis finds that carbon pricing addresses energy efficiency market failures such as externalities and imperfect energy markets. However, several market and behavioural failures in the two subsectors are identified that appear not to be addressed by carbon pricing. These include: imperfect information; principal-agent problems; and behavioural failures. In this analysis, the policies that address these market failures are identified as complementary to carbon pricing and their level of interaction with carbon pricing policies is relatively positive. These policies should be implemented when they can improve energy efficiency effectively and efficiently (and achieve other national goals such as improving socio-economic efficiency).

  12. The benefits of energy efficiency - why wait?

    NARCIS (Netherlands)

    Blok, K.; Breevoort, P. van

    2012-01-01

    Improving energy efficiency globally leads to many benefits. First and foremost, improved energy efficiency of equipment, buildings, vehicles and industrial processes will lead to a reduction of the use of electricity, heat and fuels. This will save large amounts of money. Moreover,

  13. Priorities for energy efficiency measures in agriculture

    NARCIS (Netherlands)

    Visser, de C.L.M.

    2013-01-01

    This report provides research gaps and priorities for energy efficiency measures in agriculture across Europe, based on the analysis of the Coordination and Support Action AGREE (Agriculture & Energy Efficiency) funded by the 7th research framework of the EU (www.agree.aua.gr). The analysis from

  14. Energy efficient idler for belt conveyor systems

    Energy Technology Data Exchange (ETDEWEB)

    Mukhopadhyay, A.K.; Chattopadhyay, A. [Indian School of Mines Univ., Dhanbad (India). Dept. of Mechanical Engineering and Mining; Soni, R.; Bhattnagar, M.

    2009-07-01

    In today's economic and legal environment, energy efficiency has become more important than ever. This paper proposes a new design of idler rollers for belt conveyors that could help to them even more efficient by reducing their energy consumption and also their CO{sub 2} footprint. (orig.)

  15. Energy efficiency: From regional to global cooperation

    International Nuclear Information System (INIS)

    Brendow, K.

    1994-01-01

    In developing, reforming and emerging countries in particular, institutional hurdles have hindered the introduction of energy efficient technology. The author develops the theme from two U.N. projects: A new institutional accessibility to supra-regional cooperation could provide an important stimulus for future worldwide cooperation in the field of energy efficiency. (orig.) [de

  16. The energy efficiency of onboard hydrogen storage

    DEFF Research Database (Denmark)

    Jensen, Jens Oluf; Li, Qingfeng; Bjerrum, Niels

    2010-01-01

    Global warming resulting from the use of fossil fuels is threatening the environment and energy efficiency is one of the most important ways to reduce this threat. Industry, transport and buildings are all high energy-using sectors in the world and even in the most technologically optimistic...... perspectives energy use is projected to increase in the next 50 years. How and when energy is used determines society's ability to create long-term sustainable energy systems. This is why this book, focusing on energy efficiency in these sectors and from different perspectives, is sharp and also important...

  17. Energy efficiency and social equity in South Africa: seeking convergence

    Energy Technology Data Exchange (ETDEWEB)

    Van Horen, C.; Simmonds, G. [University of Cape Town, Rondebosch (South Africa). Energy and Development Research Centre

    1998-09-01

    A key challenge facing post-apartheid South Africa is to achieve a balance between equity and efficiency goals. On the one hand, the democratic government wishes to improve the quality of life of the majority of the population, whilst on the other, the country needs an efficient and internationally competitive economy. At the more specific level of household energy policy, this efficiency-equity linkage represents a key challenge for policy-making and implementation: it is essential that convergence is sought between household energy strategies aimed at improving energy efficiency, and those strategies which improve the living conditions of the poor. This paper begins by reviewing developments in South Africa`s household energy sector in the early-1990s, most notably the national electrification plan which was launched in 1991. A second development, in 1994, was the establishment of the National Electricity Regulator. Despite the attention given to energy efficiency in the government`s new energy policy, energy efficiency considerations have not yet emerged as a major force in the energy sector. Electricity prices underestimated the environmental and other impacts of coal and nuclear-generated electricity. A range of economic and institutional reasons for this are identified and considered. Finally, two interventions on which some progress has been made, are described: these include insulation and thermal performance projects in new lost-cost houses, and a compact fluorescent lighting programme. 37 refs., 4 figs.

  18. Towards energy efficient mobile communications

    CSIR Research Space (South Africa)

    Masonta, MT

    2010-10-01

    Full Text Available The rapid growth and development of wireless communication services and applications corresponds to an increase in associated energy consumption. For broadband wireless network deployment in rural areas affected by unreliability and unavailability...

  19. Jcpenney Buying into Energy Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2013-03-01

    Jcpenney partnered with the Department of Energy (DOE) to develop and implement solutions to build new, low-energy buildings that are at least 50% below Standard 90.1-2004 of the American Society of Heating, Refrigerating, and Air- Conditioning Engineers (ASHRAE), the American National Standards Institute (ANSI), and the Illuminating Engineering Society of North America (IESNA) as part of DOE’s Commercial Building Partnerships (CBP) Program.

  20. Coordination of Energy Efficiency and Demand Response

    Energy Technology Data Exchange (ETDEWEB)

    Goldman, Charles; Reid, Michael; Levy, Roger; Silverstein, Alison

    2010-01-29

    This paper reviews the relationship between energy efficiency and demand response and discusses approaches and barriers to coordinating energy efficiency and demand response. The paper is intended to support the 10 implementation goals of the National Action Plan for Energy Efficiency's Vision to achieve all cost-effective energy efficiency by 2025. Improving energy efficiency in our homes, businesses, schools, governments, and industries - which consume more than 70 percent of the nation's natural gas and electricity - is one of the most constructive, cost-effective ways to address the challenges of high energy prices, energy security and independence, air pollution, and global climate change. While energy efficiency is an increasingly prominent component of efforts to supply affordable, reliable, secure, and clean electric power, demand response is becoming a valuable tool in utility and regional resource plans. The Federal Energy Regulatory Commission (FERC) estimated the contribution from existing U.S. demand response resources at about 41,000 megawatts (MW), about 5.8 percent of 2008 summer peak demand (FERC, 2008). Moreover, FERC recently estimated nationwide achievable demand response potential at 138,000 MW (14 percent of peak demand) by 2019 (FERC, 2009).2 A recent Electric Power Research Institute study estimates that 'the combination of demand response and energy efficiency programs has the potential to reduce non-coincident summer peak demand by 157 GW' by 2030, or 14-20 percent below projected levels (EPRI, 2009a). This paper supports the Action Plan's effort to coordinate energy efficiency and demand response programs to maximize value to customers. For information on the full suite of policy and programmatic options for removing barriers to energy efficiency, see the Vision for 2025 and the various other Action Plan papers and guides available at www.epa.gov/eeactionplan.

  1. Efficient renewable energy scenarios study for Victoria

    International Nuclear Information System (INIS)

    Armstrong, Graham

    1991-01-01

    This study examines the possible evolution of Victorian energy markets over the 1998-2030 period from technical, economic and environmental perspectives. The focus is on the technical and economic potential over the study period for renewable energy and energy efficiency to increase their share of energy markets, through their economic competitiveness with the non-renewables of oil, gas and fossil fulled electricity. The study identifies a range of energy options that have a lower impact on carbon dioxide emissions that current projections for the Victorian energy sector, together with the savings in energy, dollars and carbon dioxide emissions. In addition the macroeconomic implications of the energy paths are estimated. Specifically it examines a scenario (R-efficient renewable) where energy efficiency and renewable energy sources realise their estimated economic potential to displace non-renewable energy over the 1988-2030 period. In addition, a scenario (T-Toronto) is examined where energy markets are pushed somewhat harder, but again on an economic basis, so that what is called the Toronto target of reducing 1988 carbon dioxide (CO 2 ) emissions by 20 per cent by 2005 is attained. It is concluded that over the next forty years there is substantial economic potential in Victoria for significant gains from energy efficiency in all sectors - residential, commercial, industrial and transport - and contributions from renewable energy both in those sectors and in electricity generations. 7 figs., 5 tabs

  2. Environment-friendly building. Energy efficiency - thermal comfort - materials. Publication on the occasion of the 60th birthday of Gerd Hauser; Umweltbewusstes Bauen. Energieeffizienz - Behaglichkeit - Materialien. Festschrift zum 60. Geburtstag von Gerd Hauser

    Energy Technology Data Exchange (ETDEWEB)

    Maas, A. (ed.)

    2008-07-01

    In honour of the 60th birthday of Professor Gerd Hauser, ''father of the Energy Passport'' in this festival script 38 contributions are compiled in recognition of his work. These articles present the whole thematics of heat- and energy transfer in the building sector. The broad spectra is arranged into the sections energy efficiency, thermal comfort and materials. Constructive problems on sun protection, computer-simulated models of indoor climate, energetic sanitation of monuments taking into account preservative aspects, problems of sound emission from traffic as the constructional physical evaluation of materials in the building envelope. Furtheron the actual discussion on energy saving construction is reflected due to perspective and strategies of climate policy in Germany. The spectrum of the contribution from research and practice shows clearly, that construction physics has developed since last decades from a niche position to a comprehensive branche. (orig./GL) [German] Aus Anlass des 60. Geburtstages von Professor Gerd Hauser, dem Vater des Energiepasses, sind in dieser Festschrift in Anerkennung seines Werkes 38 Beitraege zusammengestellt. Diese stellen die gesamte Thematik der Waerme- und Energieuebertragung im Gebaeudebereich vor. Das breite Spektrum ist in die Abschnitte Energieeffizienz, Behaglichkeit und Materialien gegliedert. Behandelt werden beispielsweise baukonstruktive Fragestellungen beim Sonnenschutz, Computer simulierte Raumklimamodelle, denkmalpflegerische Aspekte bei der energetischen Sanierung, Probleme der Schalluebertragung im Verkehr sowie die bauphysikalische Bewertung von Materialien der Gebaeudehuelle. Darueber hinaus wird die aktuelle Diskussion zum Energiesparenden Bauen im Hinblick auf die Perspektiven und Strategien der Klimapolitik in Deutschland wiedergegeben. Die Bandbreite der Beitraege aus Forschung und Praxis zeigen anschaulich, dass sich die Bauphysik in den letzten Jahrzehnten aus einer

  3. Solar Thermal Energy; Energia Solar Termica

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Martinez, M; Cuesta-Santianes, M J; Cabrera Jimenez, J A

    2008-07-01

    Approximately, 50 % of worldwide primary energy consumption is done in the form of heat in applications with a temperature lower than 250 degree centigree (low-medium temperature heat). These data clearly demonstrate the great potential of solar thermal energy to substitute conventional fossil fuels, which are becoming more expensive and are responsible for global warming. Low-medium temperature solar thermal energy is mainly used to obtain domestic hot water and provide space heating. Active solar thermal systems are those related to the use of solar thermal collectors. This study is dealing with low temperature solar thermal applications, mainly focusing on active solar thermal systems. This kind of systems has been extensively growing worldwide during the last years. At the end of 2006, the collector capacity in operation worldwide equalled 127.8 GWth. The technology is considered to be already developed and actions should be aimed at favouring a greater market penetration: diffusion, financial support, regulations establishment, etc. China and USA are the leading countries with a technology based on evacuated tube collectors and unglazed collectors, respectively. The rest of the world markets are dominated by the flat glazed collectors technology. (Author) 15 refs.

  4. Energy in buildings: Efficiency, renewables and storage

    Science.gov (United States)

    Koebel, Matthias M.

    2017-07-01

    This lecture summary provides a short but comprehensive overview on the "energy and buildings" topic. Buildings account for roughly 40% of the global energy demands. Thus, an increased adoption of existing and upcoming materials and solutions for the building sector represents an enormous potential to reduce building related energy demands and greenhouse gas emissions. The central question is how the building envelope (insulation, fenestration, construction style, solar control) affects building energy demands. Compared to conventional insulation materials, superinsulation materials such as vacuum insulation panels and silica aerogel achieve the same thermal performance with significantly thinner insulation layers. With low-emissivity coatings and appropriate filler gasses, double and triple glazing reduce thermal losses by up to an order of magnitude compared to old single pane windows, while vacuum insulation and aerogel filled glazing could reduce these even further. Electrochromic and other switchable glazing solutions maximize solar gains during wintertime and minimize illumination demands whilst avoiding overheating in summer. Upon integration of renewable energy systems into the building energy supply, buildings can become both producers and consumers of energy. Combined with dynamic user behavior, temporal variations in the production of renewable energy require appropriate storage solutions, both thermal and electrical, and the integration of buildings into smart grids and energy district networks. The combination of these measures allows a reduction of the existing building stock by roughly a factor of three —a promising, but cost intensive way, to prepare our buildings for the energy turnaround.

  5. From energy efficiency towards resource efficiency within the Ecodesign Directive

    DEFF Research Database (Denmark)

    Bundgaard, Anja Marie; Mosgaard, Mette; Remmen, Arne

    2017-01-01

    on the most significant environmental impact has often resulted in a focus on energy efficiency in the use phase. Therefore, the Ecodesign Directive should continue to target resource efficiency aspects but also consider environ- mental aspects with a large improvement potential in addition to the most...... significant environmental impact. For the introduction of resource efficiency requirements into the Ecodesign Directive, these requirements have to be included in the preparatory study. It is therefore recommended to broaden the scope of the Methodology for the Ecodesign of Energy-related products and the Eco......The article examines the integration of resource efficiency into the European Ecodesign Directive. The purpose is to analyse the processes and stakeholder interactions, which formed the basis for integrating resource efficiency requirements into the implementing measure for vacuum cleaners...

  6. Energy efficiency: a recipe for success

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-09-15

    Produced in cooperation with ADEME and Enerdata, this report presents and evaluates energy efficiency policies and trends in about 90 countries around the world. It reviews the impact of energy efficiency measures and highlights the trends and results of their implementation. Energy efficiency is ''a low hanging fruit'' on the ''energy tree'' which can help address a number of objectives at the same time and at a low or negative cost: security of supply, environmental impacts, competitiveness, balance of trade, investment requirements, social aspects and others. Despite its significant potential for energy savings, energy efficiency is still far from realising this potential. Why? There is no single answer to this question. A meaningful response requires major research and an analytical effort.

  7. Energy efficiency: a recipe for success

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-09-15

    Produced in cooperation with ADEME and Enerdata, this report presents and evaluates energy efficiency policies and trends in about 90 countries around the world. It reviews the impact of energy efficiency measures and highlights the trends and results of their implementation. Energy efficiency is ''a low hanging fruit'' on the ''energy tree'' which can help address a number of objectives at the same time and at a low or negative cost: security of supply, environmental impacts, competitiveness, balance of trade, investment requirements, social aspects and others. Despite its significant potential for energy savings, energy efficiency is still far from realising this potential. Why? There is no single answer to this question. A meaningful response requires major research and an analytical effort.

  8. Energy efficient hydrocyclones; Energieffektive hydrocykloner

    Energy Technology Data Exchange (ETDEWEB)

    Korsbaek, P.; Damgaard, L.; Nielsen, John Bo; Christensen, Kent; Overgaard, J.

    2009-05-15

    The project's primary purpose is to investigate the energy savings opportunities by using hydro cyclones for separation instead of more traditional separation technologies like rotary sieves and centrifuges. The hydro cyclone plant has been tested through two campaigns. In the 2007/2008 campaign the plant was tested at the Karup potato flour factory and here the cyclone plant achieved energy savings of approx. 32% compared to the current sieve plant. This result includes consumption for a macerator shredder, pre-filtering of the gratings and additional dewatering of the pulp. In the 2008/2009 campaign the plant was tested at the Brande potato flour factory, and here the plant achieved energy savings of 54% compared with the traditional sieve system. This result includes consumption for a shear pump for the homogenization of the gratings and additional consumption for dewatering of pulp. Pre-filtering of the gratings is not thought to be necessary. (ln)

  9. Thermal energy storage in granular deposits

    Science.gov (United States)

    Ratuszny, Paweł

    2017-10-01

    Energy storage technology is crucial for the development of the use of renewable energy sources. This is a substantial constraint, however it can, to some extent, be solved by storing energy in its various forms: electrical, mechanical, chemical and thermal. This article presents the results of research in thermal properties of granular deposits. Correlation between temperature changes in the stores over a period of time and their physical properties has been studied. The results of the research have practical application in designing thermal stores based on bulk materials and ground deposits. Furthermore, the research results are significant for regeneration of the lower ground sources for heat pumps and provide data for designing ground heat exchangers for ventilation systems.

  10. Measure Guideline. Energy-Efficient Window Performance and Selection

    Energy Technology Data Exchange (ETDEWEB)

    Carmody, John [Univ. of Minnesota, St. Paul, MN (United States). NorthernSTAR; Haglund, Kerry [Univ. of Minnesota, St. Paul, MN (United States). NorthernSTAR

    2012-11-01

    This document provides guidelines for the selection of energy-efficient windows in new and existing residential construction in all U.S. climate zones. It includes information on window products, their attributes and performance. It provides cost/benefit information on window energy savings as well as information on non-energy benefits such as thermal comfort and reduced HVAC demands. The report also provides information on energy impacts of design decisions such as window orientation, total glazing area and shading devices and conditions. Information on resources for proper window installation is included as well.

  11. Toward an energy efficient community

    Science.gov (United States)

    Horn, M.

    1980-10-01

    The current oil policy of the OPEC countries means that a substantial oil shortage may be expected in the future. Conservative estimates indicate an oil shortage of 65 billion tons in the year 2000. The results of numerous new studies show that (from the technological point of view) the savings potential is high enough to achieve an absolute decrease in total energy consumption by the year 2000, provided better use is made of secondary energy sources in the form of electric power, gas, and solar heat.

  12. Energy efficiency and cleaner production

    International Nuclear Information System (INIS)

    Konstantinoff, M.; Grozeva, Iv.

    1999-01-01

    Energy is the fundamental driver of the economic growth in the todays society. It is an absolute prerequisite for the industrial development in the developed countries as well as for improving the quality of life and reducing the poverty in the developing world. It is expected that the energy demand in the developing countries will increase rapidly in the next decades, and will even exceed the level of consumption in the rich countries due to rising population and incomes. The burning of fossil fuel, however, inevitably leads to negative environmental impact, which no longer can be neglected

  13. International Congress on Energy Efficiency and Energy Related Materials

    CERN Document Server

    Bahsi, Zehra; Ozer, Mehmet; ENEFM2013

    2014-01-01

    The International Congress on Energy Efficiency and Energy Related Materials (ENEFM2013) was held on 9-12 October, 2013. This three-day congress focused on the latest developments of sustainable energy technologies, materials for sustainable energy applications and environmental & economic perspectives of energy. These proceedings include 63 peer reviewed technical papers, submitted from leading academic and research institutions from over 23 countries, representing some of the most cutting edge research available. The papers included were presented at the congress in the following sessions: General Issues Wind Energy Solar Energy Nuclear Energy Biofuels and Bioenergy Energy Storage Energy Conservation and Efficiency Energy in Buildings   Economical and Environmental Issues Environment Energy Requirements Economic Development   Materials for Sustainable Energy Hydrogen Production and Storage Photovoltaic Cells Thermionic Converters Batteries and Superconductors Phase Change Materials Fuel Cells Supercon...

  14. ENERGY EFFICIENCY. TRENDS AND INFLUENCE FACTORS

    Directory of Open Access Journals (Sweden)

    Zizi GOSCHIN

    2006-12-01

    Full Text Available Energy efficiency is correlated with many factors of influence: Gross National Income per capita, energy imports (% of energy use, renewable combustible and waste (% of total, energy use per capita, services as % of GDP and others. In this paper we are testing a model of piecewise linear regression with breakpoint in order to measure the influence of these factors on the variation of GDP per unit of energy use in Europe in the year 2003.

  15. ENERGY EFFICIENT BUILDINGS PROGRAM. CHAPTER FROM THE ENERGY AND ENVIRONMENT DIVISION ANNUAL REPORT 1979

    Energy Technology Data Exchange (ETDEWEB)

    Authors, Various

    1979-12-01

    The research reported in this volume was undertaken during FY 1979 within the Energy & Environment Division of the Lawrence Berkeley Laboratory. This volume will comprise a section of the Energy & Environment Division 1979 Annual Report, to be published in the summer of 1980. Work reported relate to: thermal performance of building envelopes; building ventilation and indoor air quality; a computer program for predicting energy use in buildings; study focused specifically on inherently energy intensive hospital buildings; energy efficient windows and lighting; potential for energy conservation and savings in the buildings sector; and evaluation of energy performance standards for residential buildings.

  16. Aquifer thermal energy storage in Finland

    Energy Technology Data Exchange (ETDEWEB)

    Iihola, H; Ala-Peijari, T; Seppaenen, H

    1988-01-01

    The rapid changes and crises in the field of energy during the 1970s and 1980s have forced us to examine the use of energy more critically and to look for new ideas. Seasonal aquifer thermal energy storage (T < 100/sup 0/C) on a large scale is one of the grey areas which have not yet been extensively explored. However, projects are currently underway in a dozen countries. In Finland there have been three demonstration projects from 1974 to 1987. International co-operation under the auspices of the International Energy Agency, Annex VI, 'Environmental and Chemical Aspects of Thermal Energy Storage in Aquifers and Research and Development of Water Treatment Methods' started in 1987. The research being undertaken in 8 countries includes several elements fundamental to hydrochemistry and biochemistry.

  17. Encouraging energy efficiency: Policies and programs

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    Successfully overcoming the barriers to higher energy efficiency requires development of policies designed for specific users and locations. Reform of energy pricing, which entails removing subsidies and beginning internalization of externalities, is critical to give technology producers and users proper signals for investment and management decisions. But while a rise in energy prices increases the amount of energy-efficiency improvement that is cost-effective, it does not remove other barriers that deter investment. Minimum efficiency standards or agreements can raise the market floor, and are important because they affect the entire market in the near-term. But they may not raise the celining very much, and do little to push the efficiency frontier. To accomplish these goals, incentives and other market-development strategies are needed. Utility programs in particular can play a key role in pushing energy efficiency beyond the level where users are likely to invest on their own. Policies, programs, and pricing should complement one another. Pricing reform alone will not overcome the many entrenched barriers to higher energy efficiency, but trying to accelerate energy efficiency improvement without addressing energy pricing problems will lead to limited success. Whether tagerting new equipment or management of existing systems, policies must reflect a thorough understanding of the particular system and an awareness of the motivations of the actors. 25 refs

  18. Governance and communication for energy efficiency

    International Nuclear Information System (INIS)

    Thomas, Stefan

    2015-01-01

    Energy efficiency has multiple benefits. It usually is a win-win option for all aspects of sustainability – environment, social objectives, and economy. We need to evaluate and communicate these multiple benefits – to citizens, companies, and policy-makers. Due to strong market barriers, effective governance and policy packages for energy efficiency are needed. Evaluation shows effective policy can achieve around 2% per year of additional energy savings.

  19. Energy efficiency of milkmaid systems in Uruguay

    International Nuclear Information System (INIS)

    LLanos, E.; Astigarraga, L.; Jacques, R.; Picasso, V.

    2013-01-01

    Reducing fossil fuel consumption and increasing energy efficiency of agricultural systems may result in environmental and economic benefits. The aim of this study was to analyze dairy production systems from an energy perspective, to identify the main variables affecting energy efficiency and fossil energy consumption, through a model of inputs and outputs. The model included as inputs energy costs of food, labor, electricity, agrochemicals, fuels and machinery, and as outputs dairy and meat production. We analyzed a database of 30 dairy farms from southern Uruguay, from the Cooperative Nacional de Product ores de Leche (Conaprole), organized in three strata based on their dairy productivity per hectare. The fossil energy use was 2.40, 3.63 y 3.80 MJ.l-1 for productivity strata low, medium and high respectively (P<0.01). Energy efficiency averages were 1.40, 0.90 y 0.86 for the same strata (P<0.01). Fossil energy of agrochemicals and fuel accounted for more than 80% of the energy consumed in the three strata. The greater the percentage of concentrate in the diet, the lower energy efficiency (P<0.01). These results suggest the existence of a negative relationship between the intensification of dairy production and energy efficiency

  20. Energy conservation through thermally insulated structures

    International Nuclear Information System (INIS)

    Abu-Dayyeh, Ayoub

    2006-01-01

    The propose of this paper is to explicate its title through investigating the different available thermal insulating materials and the various techniques of application, as practiced in Jordan, in particular, and as practiced in many parts of the world in general, which will satisfy Jordanian standards in terms of heat transmittance and thermal comfort. A brief comparison with international standards will shed some light on the stringent measures enforced in the developed world and on our striving aspirations to keep pace. The paper consists of four main parts, pseudoally divided. The first part will deal with the mechanism of heat loss and heat gain in structures during summer and winter. It will also explain the Time-lag phenomenon which is vital for providing thermal comfort inside the dwellings. The second part will evaluate the damages induced by the temperature gradients on the different elements of the structure, particularly next to exterior opening. The paper will also demonstrate the damages induced by water condensation and fungus growth on the internal surfaces of the structure and within its skeleton. A correlation between condensation and thermal insulation will be established. The third part of the paper will evaluate the different available thermal insulating materials and the application techniques which will satisfy the needs for thermal insulating and thermal comfort at the least cost possible. The criteria of an economical design shall be established. As a conclusion, the paper infers answers to the following different criteria discussed throughout the different parts of the paper. The main theme of questions can be summarized as follows: 1)How energy conservation is possible due to thermal insulation? 2)The feasibility of investing in thermal insulation? 3)Is thermal comfort and a healthy atmosphere possible inside the dwellings during all season! What are the conditions necessary to sustain them? 4)What environmental impacts can exist due to

  1. Solar applications of thermal energy storage. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Lee, C.; Taylor, L.; DeVries, J.; Heibein, S.

    1979-01-01

    A technology assessment is presented on solar energy systems which use thermal energy storage. The study includes characterization of the current state-of-the-art of thermal energy storage, an assessment of the energy storage needs of solar energy systems, and the synthesis of this information into preliminary design criteria which would form the basis for detailed designs of thermal energy storage. (MHR)

  2. Molecular Entropy, Thermal Efficiency, and Designing of Working Fluids for Organic Rankine Cycles

    Science.gov (United States)

    Wang, Jingtao; Zhang, Jin; Chen, Zhiyou

    2012-06-01

    A shortage of fossil energy sources boosts the utilization of renewable energy. Among numerous novel techniques, recovering energy from low-grade heat sources through power generation via organic Rankine cycles (ORCs) is one of the focuses. Properties of working fluids are crucial for the ORC's performance. Many studies have been done to select proper working fluids or to design new working fluids. However, no researcher has systematically investigated the relationship between molecular structures and thermal efficiencies of various working fluids for an ideal ORC. This paper has investigated the interrelations of molecular structures, molecular entropies, and thermal efficiencies of various working fluids for an ideal ORC. By calculating thermal efficiencies and molecular entropies, we find that the molecular entropy is the most appropriate thermophysical property of a working fluid to determine how much energy can be converted into work and how much cannot in a system. Generally speaking, working fluids with low entropies will generally have high thermal efficiency for an ideal ORC. Based on this understanding, the direct interrelations of molecular structures and entropies provide an explicit interrelation between molecular structures and thermal efficiencies, and thus provide an insightful direction for molecular design of novel working fluids for ORCs.

  3. Aquifer thermal energy (heat and chill) storage

    Energy Technology Data Exchange (ETDEWEB)

    Jenne, E.A. (ed.)

    1992-11-01

    As part of the 1992 Intersociety Conversion Engineering Conference, held in San Diego, California, August 3--7, 1992, the Seasonal Thermal Energy Storage Program coordinated five sessions dealing specifically with aquifer thermal energy storage technologies (ATES). Researchers from Sweden, The Netherlands, Germany, Switzerland, Denmark, Canada, and the United States presented papers on a variety of ATES related topics. With special permission from the Society of Automotive Engineers, host society for the 1992 IECEC, these papers are being republished here as a standalone summary of ATES technology status. Individual papers are indexed separately.

  4. LiH thermal energy storage device

    Science.gov (United States)

    Olszewski, M.; Morris, D.G.

    1994-06-28

    A thermal energy storage device for use in a pulsed power supply to store waste heat produced in a high-power burst operation utilizes lithium hydride as the phase change thermal energy storage material. The device includes an outer container encapsulating the lithium hydride and an inner container supporting a hydrogen sorbing sponge material such as activated carbon. The inner container is in communication with the interior of the outer container to receive hydrogen dissociated from the lithium hydride at elevated temperatures. 5 figures.

  5. Energy Efficiency and Renewable Energy in SIPs and TIPs

    Science.gov (United States)

    Tools and guides to encourage state, tribal and local agencies to consider incorporating Energy Efficiency (EE) and Renewable Energy (RE) policies and programs in their State and Tribal Implementation Plans (SIPs/TIPs).

  6. Energy Efficiency Program Administrators and Building Energy Codes

    Science.gov (United States)

    Explore how energy efficiency program administrators have helped advance building energy codes at federal, state, and local levels—using technical, institutional, financial, and other resources—and discusses potential next steps.

  7. LEAN and energy efficiency; Lean og energieffektivisering

    Energy Technology Data Exchange (ETDEWEB)

    Jespersen, Per T; Vesterager Christensen, D; Andersen, Hans [Teknologisk Institut, Energi og Klima, Taastrup (Denmark); Dam Wied, M; Dam, M [NRGi Raadgivning, Aarhus (Denmark); Thorndahl, M [Horsens Kommune, Horsens (Denmark); Weldingh, P [Lokal Energi, Viby J. (Denmark); Maagoee, P; Kristensen, Kenneth T [Viegand og Maagoee, Copenhagen (Denmark); Kirketerp Friis, A [Novozymes, Bagsvaerd (Denmark)

    2010-03-15

    By means of theoretical reports and three specific cases, the project showed how Lean principles can improve energy consulting efficiency, thus making it easier for end-users and energy consultants to record and document energy savings achieved. The three cases documented various types of extra benefits of integrating energy efficiency improvement in Lean processes. As a result of process optimisation, one manufacturing company successfully reduced both staffing and energy consumption, thus making production in Denmark competitive with out-sourced production in Asia. (LN)

  8. Modeling energy flexibility of low energy buildings utilizing thermal mass

    DEFF Research Database (Denmark)

    Foteinaki, Kyriaki; Heller, Alfred; Rode, Carsten

    2016-01-01

    In the future energy system a considerable increase in the penetration of renewable energy is expected, challenging the stability of the system, as both production and consumption will have fluctuating patterns. Hence, the concept of energy flexibility will be necessary in order for the consumption...... to match the production patterns, shifting demand from on-peak hours to off-peak hours. Buildings could act as flexibility suppliers to the energy system, through load shifting potential, provided that the large thermal mass of the building stock could be utilized for energy storage. In the present study...... the load shifting potential of an apartment of a low energy building in Copenhagen is assessed, utilizing the heat storage capacity of the thermal mass when the heating system is switched off for relieving the energy system. It is shown that when using a 4-hour preheating period before switching off...

  9. The Energy Efficiency of Onboard Hydrogen Storage

    DEFF Research Database (Denmark)

    Jensen, Jens Oluf; Vestbø, Andreas Peter; Li, Qingfeng

    2007-01-01

    A number of the most common ways of storing hydrogen are reviewed in terms of energy efficiency. Distinction is made between energy losses during regeneration and during hydrogen liberation. In the latter case, the energy might have to be provided by part of the released hydrogen, and the true...

  10. The Next Frontier in Industiral Energy Efficiency

    NARCIS (Netherlands)

    Worrell, E.

    2010-01-01

    Industry contributes directly and indirectly (through consumed electricity) about 37% of the global greenhouse gas emissions, of which over 80% is from energy use. Total energy-related emissions, which were 9.9 GtCO2 in 2004, have grown by 65% since 1971. In the near future, energy efficiency is

  11. Energy efficiency indicators. Case study, Liguria

    International Nuclear Information System (INIS)

    Ciarallo, M. A.

    2001-01-01

    The report examines the trend in the Liguria Region's energy requirements over the period 1988-1996. The trend was analysed using the regional energy balances and energy efficiency indicators, both in aggregate form and on a single sector basis. The residential sector, in particular, was singled out for an in-depth analysis using publishing and processed data [it

  12. Sustaining with efficiency the renewable energy sources

    International Nuclear Information System (INIS)

    Bano, L.; Lorenzoni, A.

    2008-01-01

    European energy policy requires actions, in favour of a more widespread diffusion of renewable energy sources. Is essential to have an efficient financial support to reduce costs. Are presented an estimated of electric power from renewable energy sources and some criticism. Is proposed a modification of green certificates market based on bilateral tradable agreements [it

  13. Modeling international trends in energy efficiency

    International Nuclear Information System (INIS)

    Stern, David I.

    2012-01-01

    I use a stochastic production frontier to model energy efficiency trends in 85 countries over a 37-year period. Differences in energy efficiency across countries are modeled as a stochastic function of explanatory variables and I estimate the model using the cross-section of time-averaged data, so that no structure is imposed on technological change over time. Energy efficiency is measured using a new energy distance function approach. The country using the least energy per unit output, given its mix of outputs and inputs, defines the global production frontier. A country's relative energy efficiency is given by its distance from the frontier—the ratio of its actual energy use to the minimum required energy use, ceteris paribus. Energy efficiency is higher in countries with, inter alia, higher total factor productivity, undervalued currencies, and smaller fossil fuel reserves and it converges over time across countries. Globally, technological change was the most important factor counteracting the energy-use and carbon-emissions increasing effects of economic growth.

  14. Structural Materials for Efficient Energy Production Systems

    International Nuclear Information System (INIS)

    Gomez Briceno, D.

    2009-01-01

    Increasing the efficiency of electric power production systems implies increasing the operating temperature above those of systems currently in operation. The viability of new systems depends completely on the availability of structural materials that withstand the operating conditions specified in the design: adequate features under mechanical stress at high temperatures and compatibility with the medium. In the case of nuclear systems (fission, fusion), an important requirement is their response to irradiation induced damage. In spite of the significant differences that exist in the design of nuclear power plants, fusion reactors, innovative fission systems, supercritical fossil plants, biomass plants, solar concentration thermal plants, etc., all of them have as a common characteristic the use of resistant materials at high temperatures. The qualification of existing materials for the new and more demanding operating conditions and the development of new materials is one of the challenges faced by the electric power production industry. The science of materials and the understanding of the basic processes that take place in structural materials on exposure to the operating conditions of energy production systems are the tools that are available to obtain safe and economically viable solutions. (Authors) 4 refs.

  15. Energy efficiency and renewables policies: Promoting efficiency or facilitating monopsony?

    International Nuclear Information System (INIS)

    Brennan, Timothy J.

    2011-01-01

    The cliche in the electricity sector, the 'cheapest power plant is the one we don't build,' neglects the benefits of the energy that plant would generate. That economy-wide perspective need not apply in considering benefits to only consumers if not building that plant was the exercise of monopsony power. A regulator maximizing consumer welfare may need to avoid rationing demand at monopsony prices. Subsidizing energy efficiency to reduce electricity demand at the margin can solve that problem, if energy efficiency and electricity use are substitutes. Renewable energy subsidies, percentage use standards, or feed in tariffs may also serve monopsony as well with sufficient inelasticity in fossil fuel electricity supply. We may not observe these effects if the regulator can set price as well as quantity, lacks buyer-side market power, or is legally precluded from denying generators a reasonable return on capital. Nevertheless, the possibility of monopsony remains significant in light of the debate as to whether antitrust enforcement should maximize consumer welfare or total welfare. - Research Highlights: → Subsidizing energy efficiency can promote monopsony, if efficiency and use are substitutes. → Renewable energy subsidies, portfolio standards, or feed-in tariffs may also promote monopsony. → Effects require buyer-side market power and ability to deny generators a reasonable return. → Monopsony is significant in light of whether antitrust should maximize consumer or total welfare.

  16. Moving around efficiently: Energy and transportation

    Directory of Open Access Journals (Sweden)

    Hermans L. J. F.

    2013-06-01

    Full Text Available Worldwide, transportation takes almost 20% of the total energy use, and more than half of the oil consumption. By far the largest part is used by cars powered by internal combustion engines. The reason is simple: oil and gasoline are ideal energy carriers for transportation, since their energy density is extremely high. However, in terms of energy efficiency the internal combustion engine has a poor performance: about 25% only. How does this compare with electric cars? What are the alternative transportation systems and their efficiencies anyway? In this lecture we will analyse the efficiency of various transport systems, using elementary physics principles. We will look at cars, buses, trains and TGVs, ships, aircraft and zeppelins. Also the efficiency of human powered vehicles will be considered. Special attention is given to future mobile energy carriers like hydrogen, batteries and super capacitors.

  17. Data analytics for simplifying thermal efficiency planning in cities.

    Science.gov (United States)

    Abdolhosseini Qomi, Mohammad Javad; Noshadravan, Arash; Sobstyl, Jake M; Toole, Jameson; Ferreira, Joseph; Pellenq, Roland J-M; Ulm, Franz-Josef; Gonzalez, Marta C

    2016-04-01

    More than 44% of building energy consumption in the USA is used for space heating and cooling, and this accounts for 20% of national CO2emissions. This prompts the need to identify among the 130 million households in the USA those with the greatest energy-saving potential and the associated costs of the path to reach that goal. Whereas current solutions address this problem by analysing each building in detail, we herein reduce the dimensionality of the problem by simplifying the calculations of energy losses in buildings. We present a novel inference method that can be used via a ranking algorithm that allows us to estimate the potential energy saving for heating purposes. To that end, we only need consumption from records of gas bills integrated with a building's footprint. The method entails a statistical screening of the intricate interplay between weather, infrastructural and residents' choice variables to determine building gas consumption and potential savings at a city scale. We derive a general statistical pattern of consumption in an urban settlement, reducing it to a set of the most influential buildings' parameters that operate locally. By way of example, the implications are explored using records of a set of (N= 6200) buildings in Cambridge, MA, USA, which indicate that retrofitting only 16% of buildings entails a 40% reduction in gas consumption of the whole building stock. We find that the inferred heat loss rate of buildings exhibits a power-law data distribution akin to Zipf's law, which provides a means to map an optimum path for gas savings per retrofit at a city scale. These findings have implications for improving the thermal efficiency of cities' building stock, as outlined by current policy efforts seeking to reduce home heating and cooling energy consumption and lower associated greenhouse gas emissions. © 2016 The Author(s).

  18. Energy efficiency. Lever for the German energy transition

    International Nuclear Information System (INIS)

    Persem, Melanie; Roesner, Sven

    2014-05-01

    This document provides some key data on energy consumption in housing and public buildings, indicates the national German objectives in terms of reduction of energy consumption, of reduction of electricity consumption, of energy efficiency, and of evolution of energy consumption in housing and public buildings and in the transport sector. It gives some data related to energy saving and achievements: energy efficiency of the German economy, improvements in housing energy efficiency and insulation, financial support for low income households, reduction of energy consumption within small-medium enterprises, the public sector, the data processing sector and public lighting, and energy saving potential by renewal of public buildings. It indicates the main measures and arrangements: information, support programs for enterprises, local communities and individuals. A graph illustrates a comparison of shares of household power consumption in France and in Germany

  19. Thermal solar energy, towards a sunny interval?

    International Nuclear Information System (INIS)

    Anon.

    2017-01-01

    While its market results are continuously decreasing, the thermal solar sector regains confidence with the perspectives of a new thermal legislation in France, a higher carbon tax and the growing volume of installed equipment. This document contains 5 articles, which themes are: The renewal of the thermal solar energy sector in France, notably for the building market, due to a new regulation and a reduction in costs; Several companies are developing large capacity thermal solar plant for industrial facilities (one of them covers 10000 m 2 ) while another company is developing an all-in-one containerised system (less than 1 MW); Another example is given with a Caribbean chemical company which use thermal solar energy for its processes, with a reduction of the fuel consumption by a 2.5 factor; The return of experience show that hybrid solar panels present some limitations, especially in terms of performances and sizing; A collective building (35 apartments) in the West of France has 100 pc of its heating needs (hot water production and space heating) satisfied with solar energy

  20. Enhancing radiative energy transfer through thermal extraction

    Directory of Open Access Journals (Sweden)

    Tan Yixuan

    2016-06-01

    Full Text Available Thermal radiation plays an increasingly important role in many emerging energy technologies, such as thermophotovoltaics, passive radiative cooling and wearable cooling clothes [1]. One of the fundamental constraints in thermal radiation is the Stefan-Boltzmann law, which limits the maximum power of far-field radiation to P0 = σT4S, where σ is the Boltzmann constant, S and T are the area and the temperature of the emitter, respectively (Fig. 1a. In order to overcome this limit, it has been shown that near-field radiations could have an energy density that is orders of magnitude greater than the Stefan-Boltzmann law [2-7]. Unfortunately, such near-field radiation transfer is spatially confined and cannot carry radiative heat to the far field. Recently, a new concept of thermal extraction was proposed [8] to enhance far-field thermal emission, which, conceptually, operates on a principle similar to oil immersion lenses and light extraction in light-emitting diodes using solid immersion lens to increase light output [62].Thermal extraction allows a blackbody to radiate more energy to the far field than the apparent limit of the Stefan-Boltzmann law without breaking the second law of thermodynamics.

  1. Power shifts: the dynamics of energy efficiency

    International Nuclear Information System (INIS)

    Edenhofer, O.; Jaeger, C.C.

    1998-01-01

    Induced technical change is crucial for tackling the problem of timing in environmental policy. However, it is by no means obvious that the state has the ability to impose its will concerning technical change on the other relevant actors. Therefore, we conceptualize power in a non-linear model with social conflict and induced technical change. The model shows how economic growth, business cycles and innovation waves interact in the dynamics of energy efficiency. We assess three different ways of government control: energy taxes, energy and labor subsidies, and energy caps. Energy taxes help to select more energy efficient technologies. However, a successful selection of such technologies presupposes that they are available in the pool of technologies. As for energy subsidies, their existence helps to explain why in contemporary economies labor productivity grows faster than energy efficiency. With an energy cap, the social network of the relevant agents may be stabilized via social norms. It seems plausible that innovation waves comprise several business cycles and that such a wave is currently in the making. Proposals to postpone policies for improving energy efficiency increase the risk of energy inefficient lock-in effects. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

  2. Financial Crisis and Energy Efficiency. Information paper

    Energy Technology Data Exchange (ETDEWEB)

    de T' Serclaes, Philippine; Gasc, Emilien; Saussay, Aurelien

    2009-10-15

    Governments have understood the importance of financing energy efficiency now. This realisation is exemplified through the central role occupied by energy efficiency in most stimulus packages. The purpose of this memo is to identify the impact of the financial and economic crisis on the evolution of public sector investments, energy efficiency policy development, and private sector investments. The paper will first identify trends which have emerged from the implementation of IEA government stimulus packages. Most relevant case studies are then provided along with lessons and challenges.

  3. Energy efficient lighting in the retail sector

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    This Good Practice Guide gives details on how energy efficient lighting can be incorporated in the brief for a lighting consultant or contractor. The advantages of energy efficiency are highlighted, and the lighting of retail stores, the introduction of energy efficiency measures, and the application of good practice are discussed. Case studies of W H Smith, Cambridge, Tesco Stores, Boots plc, the Harvey Centre, Harlow, and the National Westminster Bank plc are presented. A guide for senior executives and specialists in lighting design is also included. (UK)

  4. Energy efficient distributed computing systems

    CERN Document Server

    Lee, Young-Choon

    2012-01-01

    The energy consumption issue in distributed computing systems raises various monetary, environmental and system performance concerns. Electricity consumption in the US doubled from 2000 to 2005.  From a financial and environmental standpoint, reducing the consumption of electricity is important, yet these reforms must not lead to performance degradation of the computing systems.  These contradicting constraints create a suite of complex problems that need to be resolved in order to lead to 'greener' distributed computing systems.  This book brings together a group of outsta

  5. Thermal Transmittance and the Embodied Energy of Timber Frame Lightweight Walls Insulated with Straw and Reed

    Science.gov (United States)

    Miljan, M.; Miljan, J.

    2015-11-01

    Sustainable energy use has become topical in the whole world. Energy gives us comfort we are used to. EU and national regulations determine energy efficiency of the buildings. This is one side of the problem - energy efficiency of houses during exploitation. But the other side is primary energy content of used materials and more rational use of resources during the whole life cycle of a building. The latter value constitutes about 8 - 20% from the whole energy content. Calculations of energy efficiency of materials lead us to energy efficiency of insulation materials and to comparison of natural and industrial materials taking into account their thermal conductivity as well as their primary energy content. Case study of the test house (built in 2012) insulated with straw bales gave the result that thermal transmittance of investigated straw bale walls was according to the minimum energy efficiency requirements set in Estonia U = 0.12 - 0.22 W/m2K (for walls).

  6. Benchmarking urban energy efficiency in the UK

    International Nuclear Information System (INIS)

    Keirstead, James

    2013-01-01

    This study asks what is the ‘best’ way to measure urban energy efficiency. There has been recent interest in identifying efficient cities so that best practices can be shared, a process known as benchmarking. Previous studies have used relatively simple metrics that provide limited insight on the complexity of urban energy efficiency and arguably fail to provide a ‘fair’ measure of urban performance. Using a data set of 198 urban UK local administrative units, three methods are compared: ratio measures, regression residuals, and data envelopment analysis. The results show that each method has its own strengths and weaknesses regarding the ease of interpretation, ability to identify outliers and provide consistent rankings. Efficient areas are diverse but are notably found in low income areas of large conurbations such as London, whereas industrial areas are consistently ranked as inefficient. The results highlight the shortcomings of the underlying production-based energy accounts. Ideally urban energy efficiency benchmarks would be built on consumption-based accounts, but interim recommendations are made regarding the use of efficiency measures that improve upon current practice and facilitate wider conversations about what it means for a specific city to be energy-efficient within an interconnected economy. - Highlights: • Benchmarking is a potentially valuable method for improving urban energy performance. • Three different measures of urban energy efficiency are presented for UK cities. • Most efficient areas are diverse but include low-income areas of large conurbations. • Least efficient areas perform industrial activities of national importance. • Improve current practice with grouped per capita metrics or regression residuals

  7. Energy Saving: Scaling Network Energy Efficiency Faster than Traffic Growth

    NARCIS (Netherlands)

    Chen, Y.; Blume, O.; Gati, A.; Capone, A.; Wu, C.-E.; Barth, U.; Marzetta, T.; Zhang, H.; Xu, S.

    2013-01-01

    As the mobile traffic is expected to continue its exponential growth in the near future, energy efficiency has gradually become a must criterion for wireless network design. Three fundamental questions need to be answered before the detailed design could be carried out, namely what energy efficiency

  8. China Energy Group - Sustainable Growth Through EnergyEfficiency

    Energy Technology Data Exchange (ETDEWEB)

    Levine, Mark; Fridley, David; Lin, Jiang; Sinton, Jonathan; Zhou,Nan; Aden, Nathaniel; Huang, Joe; Price, Lynn; McKane, Aimee T.

    2006-03-20

    China is fueling its phenomenal economic growth with huge quantities of coal. The environmental consequences reach far beyond its borders--China is second only to the United States in greenhouse gas emissions. Expanding its supply of other energy sources, like nuclear power and imported oil, raises trade and security issues. Soaring electricity demand necessitates the construction of 40-70 GW of new capacity per year, creating sustained financing challenges. While daunting, the challenge of meeting China's energy needs presents a wealth of opportunities, particularly in meeting demand through improved energy efficiency and other clean energy technologies. The China Energy Group at the Lawrence Berkeley National Laboratory (LBNL) is committed to understanding these opportunities, and to exploring their implications for policy and business. We work collaboratively with energy researchers, suppliers, regulators, and consumers in China and elsewhere to: better understand the dynamics of energy use in China. Our Research Focus Encompasses Three Major Areas: Buildings, Industry, and Cross-Cutting Activities. Buildings--working to promote energy-efficient buildings and energy-efficient equipment used in buildings. Current work includes promoting the design and use of minimum energy efficiency standards and energy labeling for appliances, and assisting in the development and implementation of building codes for energy-efficient residential and commercial/public buildings. Past work has included a China Residential Energy Consumption Survey and a study of the health impacts of rural household energy use. Industry--understanding China's industrial sector, responsible for the majority of energy consumption in China. Current work includes benchmarking China's major energy-consuming industries to world best practice, examining energy efficiency trends in China's steel and cement industries, implementing voluntary energy efficiency agreements in various

  9. Energy-efficient wireless mesh infrastructures

    OpenAIRE

    Al-Hazmi, Y.; de Meer, Hermann; Hummel, Karin Anna; Meyer, Harald; Meo, Michela; Remondo Bueno, David

    2011-01-01

    The Internet comprises access segments with wired and wireless technologies. In the future, we can expect wireless mesh infrastructures (WMIs) to proliferate in this context. Due to the relatively low energy efficiency of wireless transmission, as compared to wired transmission, energy consumption of WMIs can represent a significant part of the energy consumption of the Internet as a whole. We explore different approaches to reduce energy consumption in WMIs, taking into accoun...

  10. Biogeochemical aspects of aquifer thermal energy storage

    NARCIS (Netherlands)

    Brons, H.J.

    1992-01-01

    During the process of aquifer thermal energy storage the in situ temperature of the groundwater- sediment system may fluctuate significantly. As a result the groundwater characteristics can be considerably affected by a variety of chemical, biogeochemical and microbiological

  11. Plasma thermal energy transport: theory and experiments

    International Nuclear Information System (INIS)

    Coppi, B.

    Experiments on the transport across the magnetic field of electron thermal energy are reviewed (Alcator, Frascati Torus). In order to explain the experimental results, a transport model is described that reconfirmed the need to have an expression for the local diffusion coefficient with a negative exponent of the electron temperature

  12. A Comprehensive Review of Thermal Energy Storage

    Directory of Open Access Journals (Sweden)

    Ioan Sarbu

    2018-01-01

    Full Text Available Thermal energy storage (TES is a technology that stocks thermal energy by heating or cooling a storage medium so that the stored energy can be used at a later time for heating and cooling applications and power generation. TES systems are used particularly in buildings and in industrial processes. This paper is focused on TES technologies that provide a way of valorizing solar heat and reducing the energy demand of buildings. The principles of several energy storage methods and calculation of storage capacities are described. Sensible heat storage technologies, including water tank, underground, and packed-bed storage methods, are briefly reviewed. Additionally, latent-heat storage systems associated with phase-change materials for use in solar heating/cooling of buildings, solar water heating, heat-pump systems, and concentrating solar power plants as well as thermo-chemical storage are discussed. Finally, cool thermal energy storage is also briefly reviewed and outstanding information on the performance and costs of TES systems are included.

  13. Productivity benefits of industrial energy efficiency measures

    Energy Technology Data Exchange (ETDEWEB)

    Worrell, Ernst; Laitner, John A.; Michael, Ruth; Finman, Hodayah

    2004-08-30

    We review the relationship between energy efficiency improvement measures and productivity in industry. We review over 70 industrial case studies from widely available published databases, followed by an analysis of the representation of productivity benefits in energy modeling. We propose a method to include productivity benefits in the economic assessment of the potential for energy efficiency improvement. The case-study review suggests that energy efficiency investments can provide a significant boost to overall productivity within industry. If this relationship holds, the description of energy-efficient technologies as opportunities for larger productivity improvements has significant implications for conventional economic assessments. The paper explores the implications this change in perspective on the evaluation of energy-efficient technologies for a study of the iron and steel industry in the US. This examination shows that including productivity benefits explicitly in the modeling parameters would double the cost-effective potential for energy efficiency improvement, compared to an analysis excluding those benefits. We provide suggestions for future research in this important area.

  14. Energy efficiency and CO2: is electricity the key factor?

    Energy Technology Data Exchange (ETDEWEB)

    Bamberger, Y.

    2007-07-01

    Europe must face soon to the depletion of fossil energy resources. Efficiency in end energy uses is a key to prepare this challenge. First, the report shows that significant energy efficiency capacities remain in the main economy sectors in France and Europe: buildings, industry, transportation. The key technologies, mainly electricity-driven, are briefly presented, together with the related main tracks for R and D: heat pumps, thermal insulation, induction and mechanical vapour compression for industry, plugged hybrid vehicle, LED sources for lighting. Their ability to decrease CO2 emissions is shown. Control equipment and users behaviour are pointed out, mainly with the key role of price energy with recent French experience : load shifting, peak shaving. Finally, the report shows that a firm policy, based on high performance equipments, could lead to a significant decrease of energy needs in France around 2030.

  15. Measure Guideline: Energy-Efficient Window Performance and Selection

    Energy Technology Data Exchange (ETDEWEB)

    Carmody, J.; Haglund, K.

    2012-11-01

    This document provides guidelines for the selection of energy-efficient windows in new and existing residential construction in all US climate zones. It includes information on window products, their attributes and performance. It provides cost/benefit information on window energy savings as well as information on non-energy benefits such as thermal comfort and reduced HVAC demands. The document also provides information on energy impacts of design decisions such as window orientation, total glazing area and shading devices and conditions. Information on resources for proper window installation is included as well. This document is for builders, homeowners, designers and anyone making decisions about selecting energy efficient window. It is intended to complement other Building America information and efforts.

  16. Energy Efficiency Plan 2009-2012; Energie Efficiency Plan 2009-2012

    Energy Technology Data Exchange (ETDEWEB)

    Meulen, M.M.W. (ed.)

    2009-02-15

    The aim of the Energy Efficiency Plan is to give an overview of the energy conservation plans of the Eindhoven University of Technology in Eindhoven, Netherlands, which must result in efficient use of energy conform the long-range agreements between businesses, industry and organizations and the Dutch government to improve energy efficiency (MJA3) [Dutch] Het doel van het EEP (Energie Efficiency Plan) is het in beeld brengen van de energiebesparingsplannen die leiden tot een efficienter gebruik van energie conform de MJA-3 afspraak (de derde Meerjaren Afspraak)

  17. Potentials and policy implications of energy and material efficiency improvement

    Energy Technology Data Exchange (ETDEWEB)

    Worrell, Ernst; Levine, Mark; Price, Lynn; Martin, Nathan; van den Broek, Richard; Block, Kornelis

    1997-01-01

    There is a growing awareness of the serious problems associated with the provision of sufficient energy to meet human needs and to fuel economic growth world-wide. This has pointed to the need for energy and material efficiency, which would reduce air, water and thermal pollution, as well as waste production. Increasing energy and material efficiency also have the benefits of increased employment, improved balance of imports and exports, increased security of energy supply, and adopting environmentally advantageous energy supply. A large potential exists for energy savings through energy and material efficiency improvements. Technologies are not now, nor will they be, in the foreseeable future, the limiting factors with regard to continuing energy efficiency improvements. There are serious barriers to energy efficiency improvement, including unwillingness to invest, lack of available and accessible information, economic disincentives and organizational barriers. A wide range of policy instruments, as well as innovative approaches have been tried in some countries in order to achieve the desired energy efficiency approaches. These include: regulation and guidelines; economic instruments and incentives; voluntary agreements and actions, information, education and training; and research, development and demonstration. An area that requires particular attention is that of improved international co-operation to develop policy instruments and technologies to meet the needs of developing countries. Material efficiency has not received the attention that it deserves. Consequently, there is a dearth of data on the qualities and quantities for final consumption, thus, making it difficult to formulate policies. Available data, however, suggest that there is a large potential for improved use of many materials in industrialized countries.

  18. Adsorption thermal energy storage for cogeneration in industrial batch processes: Experiment, dynamic modeling and system analysis

    International Nuclear Information System (INIS)

    Schreiber, Heike; Graf, Stefan; Lanzerath, Franz; Bardow, André

    2015-01-01

    Adsorption thermal energy storage is investigated for heat supply with cogeneration in industrial batch processes. The feasibility of adsorption thermal energy storage is demonstrated with a lab-scale prototype. Based on these experiments, a dynamic model is developed and successfully calibrated to measurement data. Thereby, a reliable description of the dynamic behavior of the adsorption thermal energy storage unit is achieved. The model is used to study and benchmark the performance of adsorption thermal energy storage combined with cogeneration for batch process energy supply. As benchmark, we consider both a peak boiler and latent thermal energy storage based on a phase change material. Beer brewing is considered as an example of an industrial batch process. The study shows that adsorption thermal energy storage has the potential to increase energy efficiency significantly; primary energy consumption can be reduced by up to 25%. However, successful integration of adsorption thermal storage requires appropriate integration of low grade heat: Preferentially, low grade heat is available at times of discharging and in demand when charging the storage unit. Thus, adsorption thermal energy storage is most beneficial if applied to a batch process with heat demands on several temperature levels. - Highlights: • A highly efficient energy supply for industrial batch processes is presented. • Adsorption thermal energy storage (TES) is analyzed in experiment and simulation. • Adsorption TES can outperform both peak boilers and latent TES. • Performance of adsorption TES strongly depends on low grade heat temperature.

  19. Energy efficiency benchmarking of energy-intensive industries in Taiwan

    International Nuclear Information System (INIS)

    Chan, David Yih-Liang; Huang, Chi-Feng; Lin, Wei-Chun; Hong, Gui-Bing

    2014-01-01

    Highlights: • Analytical tool was applied to estimate the energy efficiency indicator of energy intensive industries in Taiwan. • The carbon dioxide emission intensity in selected energy-intensive industries is also evaluated in this study. • The obtained energy efficiency indicator can serve as a base case for comparison to the other regions in the world. • This analysis results can serve as a benchmark for selected energy-intensive industries. - Abstract: Taiwan imports approximately 97.9% of its primary energy as rapid economic development has significantly increased energy and electricity demands. Increased energy efficiency is necessary for industry to comply with energy-efficiency indicators and benchmarking. Benchmarking is applied in this work as an analytical tool to estimate the energy-efficiency indicators of major energy-intensive industries in Taiwan and then compare them to other regions of the world. In addition, the carbon dioxide emission intensity in the iron and steel, chemical, cement, textile and pulp and paper industries are evaluated in this study. In the iron and steel industry, the energy improvement potential of blast furnace–basic oxygen furnace (BF–BOF) based on BPT (best practice technology) is about 28%. Between 2007 and 2011, the average specific energy consumption (SEC) of styrene monomer (SM), purified terephthalic acid (PTA) and low-density polyethylene (LDPE) was 9.6 GJ/ton, 5.3 GJ/ton and 9.1 GJ/ton, respectively. The energy efficiency of pulping would be improved by 33% if BAT (best available technology) were applied. The analysis results can serve as a benchmark for these industries and as a base case for stimulating changes aimed at more efficient energy utilization

  20. Research for energy efficiency; Forschung fuer Energieeffizienz

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-09-15

    The Federal Ministry of Economy enhanced its funding for research in the field of non-nuclear energy in the programme ''Forschung fuer Energieeffizienz'' (Research for Energy Efficiency). The programme focuses on established areas like modern power plant technologies (''Moderne Kraftwerkstechnologien''), fuel cells and hydrogen (''Brennstoffzelle, Wasserstoff''), and energy-optimized building construction (''Energieoptimiertes Bauen''). New subjects are energy-efficient towns and cities (''Energieeffiziente Stadt''), power grids for future power supply (''Netze fuer die Stromversorgung der Zukunft''), power storage (''Stromspeicher''), and electromobility (''Elektromobilitaet''). The brochure presents research and demonstration projects that illustrate the situation in 2010 when the programme was initiated. (orig.)

  1. Energy efficiency in existing detached housing

    DEFF Research Database (Denmark)

    Gram-Hanssen, Kirsten; Christensen, Toke Haunstrup

    This memo is written as an input to the German project Enef-haus on energy- efficient restoration of single-family houses in Germany. The memo contains a summary of the Danish experiences divided into three main sections: first is a short historic overview of the Danish energy policy indicating...... when different relevant instruments have been introduced to increase the energy efficiency of privately owned single-family houses. Second is a short introduction to the Danish housing sector and its energy supplies. The third and main part of the report is an examination of the most recent...

  2. Tariff regulation with energy efficiency goals

    International Nuclear Information System (INIS)

    Abrardi, Laura; Cambini, Carlo

    2015-01-01

    We study the optimal tariff structure that could induce a regulated utility to promote energy efficiency by its customers given that it is privately informed about the effectiveness of its effort on demand reduction. The regulator should optimally offer a menu of incentive compatible two-part tariffs. If the firm's energy efficiency activities have a high impact on demand reduction, the consumer should pay a high fixed fee but a low per unit price, approximating the tariff structure to a decoupling policy, which strengthens the firm's incentives to pursue energy conservation. Instead, if the firm's effort to adopt energy efficiency actions is scarcely effective, the tariff is characterized by a low fixed fee but a high price per unit of energy consumed, thus shifting the incentives for energy conservation on consumers. The optimal tariff structure also depends on the cost of the consumer's effort (in case the consumer can also adopt energy efficiency measures) and on the degree of substitutability between the consumer's and the firm's efforts. - Highlights: • We study the optimal tariff structure that induces an utility to adopt energy efficiency activities. • The regulator optimally offer a menu of incentive compatible two-part tariffs. • If energy efficiency activities have a high effectiveness, decoupling emerges as a solution. • If the energy efficiency actions are less effective, the tariff has a higher per unit price and lower fixed fee. • The optimal tariff structure also depends on the degree of substitutability between the consumer's and the firm's efforts

  3. The promotion of energy efficiency in Italy

    International Nuclear Information System (INIS)

    De Paoli, L.; Bongiolatti, L.

    2006-01-01

    In 2004 Italy introduced an obligation for electricity and gas distribution companies to reach specific objectives regarding the improvement of energy efficiency in final energy consumption. The scope of the provision is to promote investments in energy efficiency in order to meet the greenhouse gases reduction target set by the Kyoto protocol. The adoption of binding targets of energy efficiency will also lead to the development of an energy services market, modifying the traditional relation between energy dealers and final consumers, thus leading to a more efficient use of the available resources. Similar mechanisms have already been applied in other European countries (as France and United Kingdom) and will be likely introduced in other countries with the implementation of European Directive on energy end-use efficiency and energy services. This paper describes and analyzes both the measures adopted in Italy and the results obtained after the first year of operation of the mechanism. The paper is divided in six different sections. In the first part we highlight the main problems related to the development of system based on tradable white certificates. In the second part we provide a brief description of the Italian regulatory context. In the third part there is an economic analysis of investments in energy efficiency. The fourth part considers the different options that distribution companies face in order to reach the energy efficiency targets. The fifth part shows the results obtained after the first year of operation of the mechanism. Finally, we propose some possible modifications to the scheme adopted in Italy considering the results obtained and the alternative solutions already applied in France and United Kingdom [it

  4. Energy efficiency opportunities within the powder coating industry

    Energy Technology Data Exchange (ETDEWEB)

    Osbeck, Sofie; Bergek, Charlotte; Klaessbo, Anders (Swerea IVF AB, Moelndal (Sweden)), e-mail: anders.klassbo@swerea.se; Thollander, Patrik; Rohdin, Patrik (Dept. of Management and Engineering, Linkoeping Univeristy, Linkoeping (Sweden)); Harvey, Simon (Dept. of Energy and Environment, Chalmers Univ. of Technology, Goeteborg (Sweden))

    2011-06-15

    A new challenge to reduce energy usage has emerged in Swedish industry because of increasing energy costs. Energy usage in the Swedish powder coating industry is about 525 GWh annually. This industry has a long and successful record of working towards reduced environmental impact. However, they have not given priority to energy saving investments. Electricity and LPG, for which end-user prices are predicted to increase by as much as 50 - 60% by 2020, are the main energy carriers used in the plants. This paper presents the results of two detailed industrial energy audits conducted with the aim of quantifying the energy efficiency potential for the Swedish powder coating industry. Energy auditing and pinch analysis methods were used to identify possible energy housekeeping measures and heat exchanging opportunities. The biggest users of energy within the plants are the cure oven, drying oven and pre-treatment units. The energy use reduction by the housekeeping measures is 8 - 19% and by thermal heat recovery an additional 8 - 13%. These measures result in an average energy cost saving of 25% and reduction of carbon dioxide emissions of 30%. The results indicate that the powder coating industry has a total energy efficiency potential of at least 20%

  5. Fourth Annual Report on Energy Efficiency

    International Nuclear Information System (INIS)

    Di Franco, Nino; Bertini, Ilaria; Federici, Alessandro; Moneta Roberto

    2015-01-01

    Here we present the main elements of the annual report on energy efficiency 2015. The results indicate that, thanks to national policies for energy efficiency, Italy saved over 7.5 million tons of oil equivalent per year in the period 2005-2013. Compared to the National Plan for Energy Efficiency 2014, the report shows that the 2020 objectives have already been achieved for more than 20%, with residential (35.7% of the target) and industry (26.6%) among the sectors that contributed most to this result. Substantial savings could result from the agribusiness sector through the dissemination of efficient technologies in the logistics and large retail chains. A key role lies with the banks: 86% of banks has developed products dedicated to efficiency, necessitating guidelines for replicability of projects, and audit and rating to assess their quality [it

  6. Energy efficiency in future wireless broadband networks

    CSIR Research Space (South Africa)

    Masonta, MT

    2012-10-01

    Full Text Available greener economy and environment. In this research, we investigate the concept of green radio communications in wireless networks and discuss approaches for energy efficient solutions in wireless broadband network deployments. These solutions include...

  7. National Action Plan for Energy Efficiency

    Science.gov (United States)

    Provides resources for policy-makers, consumers, utilities, and others produced through NAPEE - a private-public initiative to create a sustainable, aggressive national commitment to energy efficiency through a collaborative effort of stakeholders.

  8. Building Energy Efficiency through Innovative Thermodevices (BEEIT)

    Energy Technology Data Exchange (ETDEWEB)

    Ju, Y. Sungtaek [Univ. of California, Los Angeles, CA (United States); Dunn, Bruce [Univ. of California, Los Angeles, CA (United States); Pei, Qibing [Univ. of California, Los Angeles, CA (United States); Kim, C. -J. [Univ. of California, Los Angeles, CA (United States)

    2012-12-14

    This is the final scientific/technical report for the project "Compact MEMS Electrocaloric Cooling Module" sponsored by ARAPA-E as part of its Building Energy Efficiency through Innovative Thermodevices (BEEIT) program.

  9. Determinants of energy efficiency across countries

    Science.gov (United States)

    Yao, Guolin

    With economic development, environmental concerns become more important. Economies cannot be developed without energy consumption, which is the major source of greenhouse gas emissions. Higher energy efficiency is one means of reducing emissions, but what determines energy efficiency? In this research we attempt to find answers to this question by using cross-sectional country data; that is, we examine a wide range of possible determinants of energy efficiency at the country level in an attempt to find the most important causal factors. All countries are divided into three income groups: high-income countries, middle-income countries, and low-income countries. Energy intensity is used as a measurement of energy efficiency. All independent variables belong to two categories: quantitative and qualitative. Quantitative variables are measures of the economic conditions, development indicators and energy usage situations. Qualitative variables mainly measure political, societal and economic strengths of a country. The three income groups have different economic and energy attributes. Each group has different sets of variables to explain energy efficiency. Energy prices and winter temperature are both important in high-income and middle-income countries. No qualitative variables appear in the model of high-income countries. Basic economic factors, such as institutions, political stability, urbanization level, population density, are important in low-income countries. Besides similar variables, such as macroeconomic stability and index of rule of law, the hydroelectricity share in total electric generation is also a driver of energy efficiency in middle-income countries. These variables have different policy implications for each group of countries.

  10. Modeling Pumped Thermal Energy Storage with Waste Heat Harvesting

    Science.gov (United States)

    Abarr, Miles L. Lindsey

    This work introduces a new concept for a utility scale combined energy storage and generation system. The proposed design utilizes a pumped thermal energy storage (PTES) system, which also utilizes waste heat leaving a natural gas peaker plant. This system creates a low cost utility-scale energy storage system by leveraging this dual-functionality. This dissertation first presents a review of previous work in PTES as well as the details of the proposed integrated bottoming and energy storage system. A time-domain system model was developed in Mathworks R2016a Simscape and Simulink software to analyze this system. Validation of both the fluid state model and the thermal energy storage model are provided. The experimental results showed the average error in cumulative fluid energy between simulation and measurement was +/- 0.3% per hour. Comparison to a Finite Element Analysis (FEA) model showed heat transfer. The system model was used to conduct sensitivity analysis, baseline performance, and levelized cost of energy of a recently proposed Pumped Thermal Energy Storage and Bottoming System (Bot-PTES) that uses ammonia as the working fluid. This analysis focused on the effects of hot thermal storage utilization, system pressure, and evaporator/condenser size on the system performance. This work presents the estimated performance for a proposed baseline Bot-PTES. Results of this analysis showed that all selected parameters had significant effects on efficiency, with the evaporator/condenser size having the largest effect over the selected ranges. Results for the baseline case showed stand-alone energy storage efficiencies between 51 and 66% for varying power levels and charge states, and a stand-alone bottoming efficiency of 24%. The resulting efficiencies for this case were low compared to competing technologies; however, the dual-functionality of the Bot-PTES enables it to have higher capacity factor, leading to 91-197/MWh levelized cost of energy compared to 262

  11. The energy-efficiency business - Energy utility strategies

    International Nuclear Information System (INIS)

    Loebbe, S.

    2009-01-01

    This article takes a look at the energy-efficiency business and the advantages it offers. The author quotes that energy-efficiency can contribute to making savings in primary energy, minimise the economic impact of global warming, improve reliability of supply and protect the gross national product. The advantages of new products for the efficient use of energy are reviewed and the resulting advantages for power customers are noted. Also, possibilities for the positioning of electricity suppliers in the environmental niche is noted. The partial markets involved and estimates concerning the impact of energy-efficiency measures are reviewed. Climate protection, co-operation with energy agencies, consulting services and public relations aspects are also discussed. The prerequisites for successful marketing by the utilities are examined and new business models are discussed along with the clear strategies needed. The development from an electricity utility to a system-competence partner is reviewed

  12. Energy-efficient fault-tolerant systems

    CERN Document Server

    Mathew, Jimson; Pradhan, Dhiraj K

    2013-01-01

    This book describes the state-of-the-art in energy efficient, fault-tolerant embedded systems. It covers the entire product lifecycle of electronic systems design, analysis and testing and includes discussion of both circuit and system-level approaches. Readers will be enabled to meet the conflicting design objectives of energy efficiency and fault-tolerance for reliability, given the up-to-date techniques presented.

  13. Energy Efficiency in Grocery Distribution in Denmark

    DEFF Research Database (Denmark)

    Jørgensen, Kaj

    1997-01-01

    Evaluation of the development of the energy efficiency of grocery distribution from 1960 to the present in Denmark, covering both the distribution to the shops and the shopping transport (distribution from shops to individual homes)......Evaluation of the development of the energy efficiency of grocery distribution from 1960 to the present in Denmark, covering both the distribution to the shops and the shopping transport (distribution from shops to individual homes)...

  14. Application of nanomaterials in solar thermal energy storage

    Science.gov (United States)

    Shamshirgaran, Seyed Reza; Khalaji Assadi, Morteza; Viswanatha Sharma, Korada

    2018-06-01

    Solar thermal conversion technology harvests the sun's energy, rather than fossil fuels, to generate low-cost, low/zero-emission energy in the form of heating, cooling or electrical form for residential, commercial, and industrial sectors. The advent of nanofluids and nanocomposites or phase change materials, is a new field of study which is adapted to enhance the efficiency of solar collectors. The concepts of thermal energy storage technologies are investigated and the role of nanomaterials in energy conversion is discussed. This review revealed that although the exploitation of nanomaterials will boost the performance of solar collectors almost in all cases, this would be accompanied by certain challenges such as production cost, instability, agglomeration and erosion. Earlier studies have dealt with the enhancement of thermal conductivity and heat capacity; however, less attention has been given to the facing challenges. Moreover, no exact criteria can be found for the selection of appropriate nanomaterials and their properties for a specific application. In most research studies, the nanoparticles' material and properties have not been selected based on estimated values so that all the aspects of desired application could be considered simultaneously. The wide spread use of nanomaterials can lead to cost effective solutions as well. Therefore, it seems there should be a sense of techno-economic optimization in exploiting nanomaterials for solar thermal energy storage applications. The optimization should cover the key parameters, particularly nanoparticle type, size, loading and shape which depends on the sort of application and also dispersion technology.

  15. Application of nanomaterials in solar thermal energy storage

    Science.gov (United States)

    Shamshirgaran, Seyed Reza; Khalaji Assadi, Morteza; Viswanatha Sharma, Korada

    2017-12-01

    Solar thermal conversion technology harvests the sun's energy, rather than fossil fuels, to generate low-cost, low/zero-emission energy in the form of heating, cooling or electrical form for residential, commercial, and industrial sectors. The advent of nanofluids and nanocomposites or phase change materials, is a new field of study which is adapted to enhance the efficiency of solar collectors. The concepts of thermal energy storage technologies are investigated and the role of nanomaterials in energy conversion is discussed. This review revealed that although the exploitation of nanomaterials will boost the performance of solar collectors almost in all cases, this would be accompanied by certain challenges such as production cost, instability, agglomeration and erosion. Earlier studies have dealt with the enhancement of thermal conductivity and heat capacity; however, less attention has been given to the facing challenges. Moreover, no exact criteria can be found for the selection of appropriate nanomaterials and their properties for a specific application. In most research studies, the nanoparticles' material and properties have not been selected based on estimated values so that all the aspects of desired application could be considered simultaneously. The wide spread use of nanomaterials can lead to cost effective solutions as well. Therefore, it seems there should be a sense of techno-economic optimization in exploiting nanomaterials for solar thermal energy storage applications. The optimization should cover the key parameters, particularly nanoparticle type, size, loading and shape which depends on the sort of application and also dispersion technology.

  16. Thermal Storage Systems Assessment for Energy Sustainability in Housing Units

    Directory of Open Access Journals (Sweden)

    Tania I. Lagunes Vega

    2016-04-01

    Full Text Available In order to achieve greater enhancements in energy sustainability for housing, the function and efficiency of two different passive cooling systems were studied: encapsulated water in recycled bottles of Polyethylene terephthalate (PET and polystyrene plates, in comparison with standard concrete slab systems, which are customarily used in housing. Experiments were placed over a tile surface, in which temperature changes were monitored for a period of 20 days from 08:00 to 20:00. The efficiency of passive thermal storage systems was endorsed through statistical analysis using the “SPSS” software. This resulted in a 17% energy saving, thus promoting energy sustainability in housing units, which reduces the use of electrical appliances required to stabilize conditions to achieve optimum thermal comfort for the human body inside a house, therefore, reducing electrical power consumption, CO2 emissions to the atmosphere and generating savings. Due to the complexity of a system with temperature changes, a fractal analysis was performed for each experimental system, using the “Benoit” software (V.1.3 with self-compatible tools of rescaled range (R/S and a wavelets method, showing that the thermal fluctuations on the tiles with the thermal storage system adapt to the rescaled range analysis and the regular tiles adapt to the wavelets method.

  17. Recycled Thermal Energy from High Power Light Emitting Diode Light Source.

    Science.gov (United States)

    Ji, Jae-Hoon; Jo, GaeHun; Ha, Jae-Geun; Koo, Sang-Mo; Kamiko, Masao; Hong, JunHee; Koh, Jung-Hyuk

    2018-09-01

    In this research, the recycled electrical energy from wasted thermal energy in high power Light Emitting Diode (LED) system will be investigated. The luminous efficiency of lights has been improved in recent years by employing the high power LED system, therefore energy efficiency was improved compared with that of typical lighting sources. To increase energy efficiency of high power LED system further, wasted thermal energy should be re-considered. Therefore, wasted thermal energy was collected and re-used them as electrical energy. The increased electrical efficiency of high power LED devices was accomplished by considering the recycled heat energy, which is wasted thermal energy from the LED. In this work, increased electrical efficiency will be considered and investigated by employing the high power LED system, which has high thermal loss during the operating time. For this research, well designed thermoelement with heat radiation system was employed to enhance the collecting thermal energy from the LED system, and then convert it as recycled electrical energy.

  18. Simulation of energy- efficient building prototype using different insulating materials

    Science.gov (United States)

    Ouhaibi, Salma; Belouaggadia, Naoual; Lbibb, Rachid; Ezzine, Mohammed

    2018-05-01

    The objective of this work is to analyze the energetic efficiency of an individual building including an area of 130 m2 multi-zone, located in the region of FEZ which is characterized by a very hot and dry climate in summer and a quite cold one in winter, by incorporating insulating materials. This study was performed using TRNSYS V16 simulation software during a typical year of the FEZ region. Our simulation consists in developing a comparative study of two types of polystyrene and silica-aerogel insulation materials, in order to determine the best thermal performance. The results show that the thermal insulation of the building envelope is among the most effective solutions that give a significant reduction in energy requirements. Similarly, the use of silica-aerogels gives a good thermal performance, and therefore a good energy gain.

  19. Analysis of the impact of storage conditions on the thermal recovery efficiency of low-temperature ATES systems

    NARCIS (Netherlands)

    Bloemendal, Martin; Hartog, Niels

    Aquifer thermal energy storage (ATES) is a technology with worldwide potential to provide sustainable space heating and cooling using groundwater stored at different temperatures. The thermal recovery efficiency is one of the main parameters that determines the overall energy savings of ATES systems

  20. Analysis of the impact of storage conditions on the thermal recovery efficiency of low-temperature ATES systems

    NARCIS (Netherlands)

    Bloemendal, J.M.; Hartog, Niels

    2018-01-01

    Aquifer thermal energy storage (ATES) is a technology with worldwide potential to provide sustainable space heating and cooling using groundwater stored at different temperatures. The thermal recovery efficiency is one of the main parameters that determines the overall energy savings of ATES systems