The Role of Bio-productivity on Bio-energy Yields

Directory of Open Access Journals (Sweden)

Marc J. J. Janssens

2009-04-01

Full Text Available The principal photosynthetic pathways convert solar energy differently depending on the environmental conditions and the plant morphotype. Partitioning of energy storage within crops will vary according to environmental and seasonal conditions as well. Highest energy concentration is found in terpens like latex and, to a lesser extent, in lipids. Ideally, we want plant ingredients with high energy content easily amenable to ready-to-use bio-fuel. Generally, these crops are adapted to drier areas and tend to save on eco-volume space. Competition with food crops could be avoided by fetching energy from cheap agricultural by-products or waste products such as bagasse in the sugar cane. This would in fact mean that reducing power of agricultural residues should be extracted from the biomass through non-photosynthetic processes like animal ingestion or industrial bio-fermentation. Conversion and transformation efficiencies in the production chain are illustrated for some relevant crops in the light of the maximum power theorem.

Evaluating Maximum Wind Energy Exploitation in Active Distribution Networks

DEFF Research Database (Denmark)

Siano, Pierluigi; Chen, Peiyuan; Chen, Zhe

2010-01-01

The increased spreading of distributed and renewable generation requires moving towards active management of distribution networks. In this paper, in order to evaluate maximum wind energy exploitation in active distribution networks, a method based on a multi-period optimal power flow (OPF......) analysis is proposed. Active network management schemes such as coordinated voltage control, energy curtailment and power factor control are integrated in the method in order to investigate their impacts on the maximization of wind energy exploitation. Some case studies, using real data from a Danish...... distribution system, confirmed the effectiveness of the proposed method in evaluating the optimal applications of active management schemes to increase wind energy harvesting without costly network reinforcement for the connection of wind generation....

Electron energy spectrum and maximum disruption angle under multi-photon beamstrahlung

Energy Technology Data Exchange (ETDEWEB)

Yokoya, Kaoru; Chen, Pisin

1989-03-01

The final electron energy spectrum under multi-photon beamstrahlung process is derived analytically in the classical and the intermediate regimes. The maximum disruption angle from the low energy tail of the spectrum is also estimated. The results are then applied to the TLC and the CLIC parameters. 6 refs., 1 fig., 1 tab.

Different types of maximum power point tracking techniques for renewable energy systems: A survey

Science.gov (United States)

Khan, Mohammad Junaid; Shukla, Praveen; Mustafa, Rashid; Chatterji, S.; Mathew, Lini

2016-03-01

Global demand for electricity is increasing while production of energy from fossil fuels is declining and therefore the obvious choice of the clean energy source that is abundant and could provide security for development future is energy from the sun. In this paper, the characteristic of the supply voltage of the photovoltaic generator is nonlinear and exhibits multiple peaks, including many local peaks and a global peak in non-uniform irradiance. To keep global peak, MPPT is the important component of photovoltaic systems. Although many review articles discussed conventional techniques such as P & O, incremental conductance, the correlation ripple control and very few attempts have been made with intelligent MPPT techniques. This document also discusses different algorithms based on fuzzy logic, Ant Colony Optimization, Genetic Algorithm, artificial neural networks, Particle Swarm Optimization Algorithm Firefly, Extremum seeking control method and hybrid methods applied to the monitoring of maximum value of power at point in systems of photovoltaic under changing conditions of irradiance.

Hydrogen Production from Optimal Wind-PV Energies Systems

Energy Technology Data Exchange (ETDEWEB)

Tafticht, T.; Agbossou, K. [Institut de recherche sur l hydrogene, Universite du Quebec - Trois-Rivieres, C.P. 500, Trois-Rivieres, (Ciheam), G9A 5H7, (Canada)

2006-07-01

Electrolytic hydrogen offers a promising alternative for long-term energy storage of renewable energies (RE). A stand-alone RE system based on hydrogen production has been developed at the Hydrogen Research Institute and successfully tested for automatic operation with designed control devices. The system is composed of a wind turbine, a photovoltaic (PV) array, an electrolyser, batteries for buffer energy storage, hydrogen and oxygen storage tanks, a fuel cell, AC and DC loads, power conditioning devices and different sensors. The long-term excess energy with respect to load demand has been sent to the electrolyser for hydrogen production and then the fuel cell has utilised this stored hydrogen to produce electricity when there were insufficient wind and solar energies with respect to load requirements. The RE system components have substantially different voltage-current characteristics and they are integrated on the DC bus through power conditioning devices for optimal operation by using the developed Maximum Power Point Tracking (MPPT) control method. The experimental results show that the power gain obtained by this method clearly increases the hydrogen production and storage rate from wind-PV systems. (authors)

Hydrogen Production from Optimal Wind-PV Energies Systems

International Nuclear Information System (INIS)

T Tafticht; K Agbossou

2006-01-01

Electrolytic hydrogen offers a promising alternative for long-term energy storage of renewable energies (RE). A stand-alone RE system based on hydrogen production has been developed at the Hydrogen Research Institute and successfully tested for automatic operation with designed control devices. The system is composed of a wind turbine, a photovoltaic (PV) array, an electrolyzer, batteries for buffer energy storage, hydrogen and oxygen storage tanks, a fuel cell, AC and DC loads, power conditioning devices and different sensors. The long-term excess energy with respect to load demand has been sent to the electrolyser for hydrogen production and then the fuel cell has utilised this stored hydrogen to produce electricity when there were insufficient wind and solar energies with respect to load requirements. The RE system components have substantially different voltage-current characteristics and they are integrated on the DC bus through power conditioning devices for optimal operation by using the developed Maximum Power Point Tracking (MPPT) control method. The experimental results show that the power gain obtained by this method clearly increases the hydrogen production and storage rate from wind-PV systems. (authors)

Hydrogen Production from Optimal Wind-PV Energies Systems

International Nuclear Information System (INIS)

Tafticht, T.; Agbossou, K.

2006-01-01

Electrolytic hydrogen offers a promising alternative for long-term energy storage of renewable energies (RE). A stand-alone RE system based on hydrogen production has been developed at the Hydrogen Research Institute and successfully tested for automatic operation with designed control devices. The system is composed of a wind turbine, a photovoltaic (PV) array, an electrolyser, batteries for buffer energy storage, hydrogen and oxygen storage tanks, a fuel cell, AC and DC loads, power conditioning devices and different sensors. The long-term excess energy with respect to load demand has been sent to the electrolyser for hydrogen production and then the fuel cell has utilised this stored hydrogen to produce electricity when there were insufficient wind and solar energies with respect to load requirements. The RE system components have substantially different voltage-current characteristics and they are integrated on the DC bus through power conditioning devices for optimal operation by using the developed Maximum Power Point Tracking (MPPT) control method. The experimental results show that the power gain obtained by this method clearly increases the hydrogen production and storage rate from wind-PV systems. (authors)

Hydrogen Production from Optimal Wind-PV Energies Systems

Energy Technology Data Exchange (ETDEWEB)

T Tafticht; K Agbossou [Institut de recherche sur l hydrogene, Universite du Quebec - Trois-Rivieres, C.P. 500, Trois-Rivieres, (Ciheam), G9A 5H7, (Canada)

2006-07-01

Electrolytic hydrogen offers a promising alternative for long-term energy storage of renewable energies (RE). A stand-alone RE system based on hydrogen production has been developed at the Hydrogen Research Institute and successfully tested for automatic operation with designed control devices. The system is composed of a wind turbine, a photovoltaic (PV) array, an electrolyzer, batteries for buffer energy storage, hydrogen and oxygen storage tanks, a fuel cell, AC and DC loads, power conditioning devices and different sensors. The long-term excess energy with respect to load demand has been sent to the electrolyser for hydrogen production and then the fuel cell has utilised this stored hydrogen to produce electricity when there were insufficient wind and solar energies with respect to load requirements. The RE system components have substantially different voltage-current characteristics and they are integrated on the DC bus through power conditioning devices for optimal operation by using the developed Maximum Power Point Tracking (MPPT) control method. The experimental results show that the power gain obtained by this method clearly increases the hydrogen production and storage rate from wind-PV systems. (authors)

EFFECTIVENESS OF SELECTION OF WHEAT TO MODERN REQUIREMENTS FOR SUSTAINABLE DEVELOPMENT OF AGRICULTURE III. ENERGY PRODUCTIVITY OF CROPS

Directory of Open Access Journals (Sweden)

Elisaveta Vasileva

2014-03-01

Full Text Available Aim of the study was to conclude on adaptation of modern varieties to the requirements of sustainable agriculture and hence the effectiveness of their methods of selection with respect to these requirements. The comparison between genotypes in two directions - by the selection methods by which they were established and according to the time of their creation. Energy assessment shows that the gross energy yield of grain is higher ( in average 5% over standard for varieties produced by the methods of the Intervarietal hybridization and during the period 1995 to 1999. While absolute maximum values of the energy productivity of grain (at N18 and maximum average total gross energy productivity of crops (4% above standard were detected in genotypes generated by the methods of mutagenesis by irradiation with gamma rays. Absolute maximum value of the energy productivity of crops were reported in cultivar Zdravko (at N18, which was established by the method of plant biotechnology by combining and somaclonal variation.

Formulation of charged-particle pseudorapidity distribution in Au-Au collisions at the maximum RHIC energy

International Nuclear Information System (INIS)

Fu-Hu, Liu; Dong-Hai, Zhang; Mai-Ying, Duan

2003-01-01

The pseudorapidity distributions of charged particles produced in relativistic heavy-ion collider experiment are analyzed by the thermalized two-cylinder model. The calculated results are compared and found to be in agreement with the experimental data of Au-Au collisions at the maximum RHIC energy (the energy in the center-of-mass reference frame is √s = 200 A GeV) which is the maximum energy in the present accelerator energy region. (authors)

The Maximum Entropy Production Principle: Its Theoretical Foundations and Applications to the Earth System

Directory of Open Access Journals (Sweden)

Axel Kleidon

2010-03-01

Full Text Available The Maximum Entropy Production (MEP principle has been remarkably successful in producing accurate predictions for non-equilibrium states. We argue that this is because the MEP principle is an effective inference procedure that produces the best predictions from the available information. Since all Earth system processes are subject to the conservation of energy, mass and momentum, we argue that in practical terms the MEP principle should be applied to Earth system processes in terms of the already established framework of non-equilibrium thermodynamics, with the assumption of local thermodynamic equilibrium at the appropriate scales.

Energy-Efficient Algorithm for Sensor Networks with Non-Uniform Maximum Transmission Range

Directory of Open Access Journals (Sweden)

Yimin Yu

2011-06-01

Full Text Available In wireless sensor networks (WSNs, the energy hole problem is a key factor affecting the network lifetime. In a circular multi-hop sensor network (modeled as concentric coronas, the optimal transmission ranges of all coronas can effectively improve network lifetime. In this paper, we investigate WSNs with non-uniform maximum transmission ranges, where sensor nodes deployed in different regions may differ in their maximum transmission range. Then, we propose an Energy-efficient algorithm for Non-uniform Maximum Transmission range (ENMT, which can search approximate optimal transmission ranges of all coronas in order to prolong network lifetime. Furthermore, the simulation results indicate that ENMT performs better than other algorithms.

Maximum production rate optimization for sulphuric acid decomposition process in tubular plug-flow reactor

International Nuclear Information System (INIS)

Wang, Chao; Chen, Lingen; Xia, Shaojun; Sun, Fengrui

2016-01-01

A sulphuric acid decomposition process in a tubular plug-flow reactor with fixed inlet flow rate and completely controllable exterior wall temperature profile and reactants pressure profile is studied in this paper by using finite-time thermodynamics. The maximum production rate of the aimed product SO 2 and the optimal exterior wall temperature profile and reactants pressure profile are obtained by using nonlinear programming method. Then the optimal reactor with the maximum production rate is compared with the reference reactor with linear exterior wall temperature profile and the optimal reactor with minimum entropy generation rate. The result shows that the production rate of SO 2 of optimal reactor with the maximum production rate has an increase of more than 7%. The optimization of temperature profile has little influence on the production rate while the optimization of reactants pressure profile can significantly increase the production rate. The results obtained may provide some guidelines for the design of real tubular reactors. - Highlights: • Sulphuric acid decomposition process in tubular plug-flow reactor is studied. • Fixed inlet flow rate and controllable temperature and pressure profiles are set. • Maximum production rate of aimed product SO 2 is obtained. • Corresponding optimal temperature and pressure profiles are derived. • Production rate of SO 2 of optimal reactor increases by 7%.

Ion energy loss at maximum stopping power in a laser-generated plasma

International Nuclear Information System (INIS)

Cayzac, W.

2013-01-01

In the frame of this thesis, a new experimental setup for the measurement of the energy loss of carbon ions at maximum stopping power in a hot laser-generated plasma has been developed and successfully tested. In this parameter range where the projectile velocity is of the same order of magnitude as the thermal velocity of the plasma free electrons, large uncertainties of up to 50% are present in the stopping-power description. To date, no experimental data are available to perform a theory benchmarking. Testing the different stopping theories is yet essential for inertial confinement fusion and in particular for the understanding of the alpha-particle heating of the thermonuclear fuel. Here, for the first time, precise measurements were carried out in a reproducible and entirely characterized beam-plasma configuration. It involved a nearly fully-stripped ion beam probing a homogeneous fully-ionized plasma. This plasma was generated by irradiating a thin carbon foil with two high-energy laser beams and features a maximum electron temperature of 200 eV. The plasma conditions were simulated with a two-dimensional radiative hydrodynamic code, while the ion-beam charge-state distribution was predicted by means of a Monte-Carlo code describing the charge-exchange processes of projectile ions in plasma. To probe at maximum stopping power, high-frequency pulsed ion bunches were decelerated to an energy of 0.5 MeV per nucleon. The ion energy loss was determined by a time-of-flight measurement using a specifically developed chemical-vapor-deposition diamond detector that was screened against any plasma radiation. A first experimental campaign was carried out using this newly developed platform, in which a precision better than 200 keV on the energy loss was reached. This allowed, via the knowledge of the plasma and of the beam parameters, to reliably test several stopping theories, either based on perturbation theory or on a nonlinear T-Matrix formalism. A preliminary

Small scale wind energy harvesting with maximum power tracking

Directory of Open Access Journals (Sweden)

Joaquim Azevedo

2015-07-01

Full Text Available It is well-known that energy harvesting from wind can be used to power remote monitoring systems. There are several studies that use wind energy in small-scale systems, mainly with wind turbine vertical axis. However, there are very few studies with actual implementations of small wind turbines. This paper compares the performance of horizontal and vertical axis wind turbines for energy harvesting on wireless sensor network applications. The problem with the use of wind energy is that most of the time the wind speed is very low, especially at urban areas. Therefore, this work includes a study on the wind speed distribution in an urban environment and proposes a controller to maximize the energy transfer to the storage systems. The generated power is evaluated by simulation and experimentally for different load and wind conditions. The results demonstrate the increase in efficiency of wind generators that use maximum power transfer tracking, even at low wind speeds.

Energy consumption in the manufacture of sawn goods and wood-based panel products

Energy Technology Data Exchange (ETDEWEB)

Usenius, A.

1983-01-01

A study was made of energy consumption in 1979 and the possibilities of saving energy in the sawmill, plywood, particle board, fibreboard, joinery, wooden houses, glulam, and wood preservation industries. The energy consumption per product unit is minimum in sawmilling, 1.38 GJ/cubic meters and maximum in fibreboard manufacturing, 9.98 GJ/t. In plywood production, the energy consumption (6.95 GJ/cubic meters) is about double that in particleboard production (3.40 GJ/cubic meters). The main part of the energy (70-85%) is heat. In the drying process about 70-85% of total energy is used in individual processes. Over half (53.9%) of the total energy consumption is in the sawmill industry, 19.2% in the plywood industry, 12.2% in the particleboard industry, and 7.2% in the fibreboard industry.

Estimation of the Maximum Theoretical Productivity of Fed-Batch Bioreactors

Energy Technology Data Exchange (ETDEWEB)

Bomble, Yannick J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); St. John, Peter C [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Crowley, Michael F [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2017-10-18

A key step towards the development of an integrated biorefinery is the screening of economically viable processes, which depends sharply on the yields and productivities that can be achieved by an engineered microorganism. In this study, we extend an earlier method which used dynamic optimization to find the maximum theoretical productivity of batch cultures to explicitly include fed-batch bioreactors. In addition to optimizing the intracellular distribution of metabolites between cell growth and product formation, we calculate the optimal control trajectory of feed rate versus time. We further analyze how sensitive the productivity is to substrate uptake and growth parameters.

Radiation pressure acceleration: The factors limiting maximum attainable ion energy

Energy Technology Data Exchange (ETDEWEB)

Bulanov, S. S.; Esarey, E.; Schroeder, C. B. [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Bulanov, S. V. [KPSI, National Institutes for Quantum and Radiological Science and Technology, Kizugawa, Kyoto 619-0215 (Japan); A. M. Prokhorov Institute of General Physics RAS, Moscow 119991 (Russian Federation); Esirkepov, T. Zh.; Kando, M. [KPSI, National Institutes for Quantum and Radiological Science and Technology, Kizugawa, Kyoto 619-0215 (Japan); Pegoraro, F. [Physics Department, University of Pisa and Istituto Nazionale di Ottica, CNR, Pisa 56127 (Italy); Leemans, W. P. [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Physics Department, University of California, Berkeley, California 94720 (United States)

2016-05-15

Radiation pressure acceleration (RPA) is a highly efficient mechanism of laser-driven ion acceleration, with near complete transfer of the laser energy to the ions in the relativistic regime. However, there is a fundamental limit on the maximum attainable ion energy, which is determined by the group velocity of the laser. The tightly focused laser pulses have group velocities smaller than the vacuum light speed, and, since they offer the high intensity needed for the RPA regime, it is plausible that group velocity effects would manifest themselves in the experiments involving tightly focused pulses and thin foils. However, in this case, finite spot size effects are important, and another limiting factor, the transverse expansion of the target, may dominate over the group velocity effect. As the laser pulse diffracts after passing the focus, the target expands accordingly due to the transverse intensity profile of the laser. Due to this expansion, the areal density of the target decreases, making it transparent for radiation and effectively terminating the acceleration. The off-normal incidence of the laser on the target, due either to the experimental setup, or to the deformation of the target, will also lead to establishing a limit on maximum ion energy.

Wave Energy Converter Annual Energy Production Uncertainty Using Simulations

Directory of Open Access Journals (Sweden)

Clayton E. Hiles

2016-09-01

Full Text Available Critical to evaluating the economic viability of a wave energy project is: (1 a robust estimate of the electricity production throughout the project lifetime and (2 an understanding of the uncertainty associated with said estimate. Standardization efforts have established mean annual energy production (MAEP as the metric for quantification of wave energy converter (WEC electricity production and the performance matrix approach as the appropriate method for calculation. General acceptance of a method for calculating the MAEP uncertainty has not yet been achieved. Several authors have proposed methods based on the standard engineering approach to error propagation, however, a lack of available WEC deployment data has restricted testing of these methods. In this work the magnitude and sensitivity of MAEP uncertainty is investigated. The analysis is driven by data from simulated deployments of 2 WECs of different operating principle at 4 different locations. A Monte Carlo simulation approach is proposed for calculating the variability of MAEP estimates and is used to explore the sensitivity of the calculation. The uncertainty of MAEP ranged from 2%–20% of the mean value. Of the contributing uncertainties studied, the variability in the wave climate was found responsible for most of the uncertainty in MAEP. Uncertainty in MAEP differs considerably between WEC types and between deployment locations and is sensitive to the length of the input data-sets. This implies that if a certain maximum level of uncertainty in MAEP is targeted, the minimum required lengths of the input data-sets will be different for every WEC-location combination.

Paving the road to maximum productivity.

Science.gov (United States)

Holland, C

1998-01-01

"Job security" is an oxymoron in today's environment of downsizing, mergers, and acquisitions. Workers find themselves living by new rules in the workplace that they may not understand. How do we cope? It is the leader's charge to take advantage of this chaos and create conditions under which his or her people can understand the need for change and come together with a shared purpose to effect that change. The clinical laboratory at Arkansas Children's Hospital has taken advantage of this chaos to down-size and to redesign how the work gets done to pave the road to maximum productivity. After initial hourly cutbacks, the workers accepted the cold, hard fact that they would never get their old world back. They set goals to proactively shape their new world through reorganizing, flexing staff with workload, creating a rapid response laboratory, exploiting information technology, and outsourcing. Today the laboratory is a lean, productive machine that accepts change as a way of life. We have learned to adapt, trust, and support each other as we have journeyed together over the rough roads. We are looking forward to paving a new fork in the road to the future.

An automotive thermoelectric-photovoltaic hybrid energy system using maximum power point tracking

International Nuclear Information System (INIS)

Zhang Xiaodong; Chau, K.T.

2011-01-01

In recent years, there has been active research on exhaust gas waste heat energy recovery for automobiles. Meanwhile, the use of solar energy is also proposed to promote on-board renewable energy and hence to improve their fuel economy. In this paper, a new thermoelectric-photovoltaic (TE-PV) hybrid energy system is proposed and implemented for automobiles. The key is to newly develop the power conditioning circuit using maximum power point tracking so that the output power of the proposed TE-PV hybrid energy system can be maximized. An experimental system is prototyped and tested to verify the validity of the proposed system.

Thermoelectric automotive waste heat energy recovery using maximum power point tracking

International Nuclear Information System (INIS)

Yu Chuang; Chau, K.T.

2009-01-01

This paper proposes and implements a thermoelectric waste heat energy recovery system for internal combustion engine automobiles, including gasoline vehicles and hybrid electric vehicles. The key is to directly convert the heat energy from automotive waste heat to electrical energy using a thermoelectric generator, which is then regulated by a DC-DC Cuk converter to charge a battery using maximum power point tracking. Hence, the electrical power stored in the battery can be maximized. Both analysis and experimental results demonstrate that the proposed system can work well under different working conditions, and is promising for automotive industry.

Evaluation of maximum power point tracking in hydrokinetic energy conversion systems

Directory of Open Access Journals (Sweden)

Jahangir Khan

2015-11-01

Full Text Available Maximum power point tracking is a mature control issue for wind, solar and other systems. On the other hand, being a relatively new technology, detailed discussion on power tracking of hydrokinetic energy conversion systems are generally not available. Prior to developing sophisticated control schemes for use in hydrokinetic systems, existing know-how in wind or solar technologies can be explored. In this study, a comparative evaluation of three generic classes of maximum power point scheme is carried out. These schemes are (a tip speed ratio control, (b power signal feedback control, and (c hill climbing search control. In addition, a novel concept for maximum power point tracking: namely, extremum seeking control is introduced. Detailed and validated system models are used in a simulation environment. Potential advantages and drawbacks of each of these schemes are summarised.

A climate-change policy induced shift from innovations in carbon-energy production to carbon-energy savings

International Nuclear Information System (INIS)

Gerlagh, Reyer

2008-01-01

We develop an endogenous growth model with capital, labor and carbon-energy as production factors and three technology variables that measure accumulated innovations for carbon-energy production, carbon-energy savings, and neutral growth. All markets are complete and perfect, except for research, for which we assume that the marginal social benefits exceed the marginal private benefits by factor four. The model constants are calibrated so that the model reproduces the relevant global trends over the 1970-2000 period. The model contains a simple climate module, and is used to assess the impact of Induced Technological Change (ITC) for a policy that aims at a maximum level of atmospheric CO 2 concentration (450 ppmv). ITC is shown to reduce the required carbon tax by more than a factor 2, and to reduce costs of such a policy by half. When we do not constrain aggregate R and D expenditures to benchmark levels, costs are further reduced. Numerical simulations show that knowledge accumulation shifts from energy production to energy saving technology. We discuss reasons for differences between our results and earlier results reported in the literature. (author)

Energy productivity, fertilization rate and profitability of wheat production after various predecessors II.Profitability of wheat production

Directory of Open Access Journals (Sweden)

Z. Uhr

2016-03-01

Full Text Available Abstract. In the course of our study on the adaptation of modern genotypes common winter wheat (Triticum aestivum to the requirements of sustainable agriculture data were received concerning the influence of the predecessor and nitrogen fertilizer rate on energy efficiency and recyclable nitrogen fertilization and profitability of productivity.We share these data with the scientific community, as they are up-to-date and informative in both theoretical and practical aspects. The analyses are based on data from field experiments fertilizer derived after predecessor cereals – regular crop of sorghum, millet, maize and legumes after predecessor - separate sowing of chickpeas. Energy efficiency of nitrogen fertilization was calculated as the ratio between the energy supplied in the additional grain yield and energy input in the form of fertilizers. Refundable efficiency of nitrogen fertilization is the additional amount of nitrogen accumulated in the grain, with respect to the applied nitrogen fertilization. Economic profitability of production is evaluated by coefficient R = P/Ra (ratio of benefits/costs. The results show that energy efficiency and recyclable nitrogen fertilization are on average five times higher after cereal than after legumes predecessor, and decreased with increasing the fertilizer rate, the decrease was statistically significant only for the first item (exponent. Profitability ratio of production after the introduction of legumes predecessor in crop rotation increases by an average of 42% and retains maximum values of fertilization levels 0.06, 0.12 and 0.18 t/ha nitrogen. Profitability of wheat production using pre-legumes crop is not determined by the parameters nitrogen fertilizer rate and energy efficiency of nitrogen fertilization and refundable efficiency of nitrogen fertilization.

Theory and application of maximum magnetic energy in toroidal plasmas

International Nuclear Information System (INIS)

Chu, T.K.

1992-02-01

The magnetic energy in an inductively driven steady-state toroidal plasma is a maximum for a given rate of dissipation of energy (Poynting flux). A purely resistive steady state of the piecewise force-free configuration, however, cannot exist, as the periodic removal of the excess poloidal flux and pressure, due to heating, ruptures the static equilibrium of the partitioning rational surfaces intermittently. The rupture necessitates a plasma with a negative q'/q (as in reverse field pinches and spheromaks) to have the same α in all its force-free regions and with a positive q'/q (as in tokamaks) to have centrally peaked α's

Uninterrupted thermoelectric energy harvesting using temperature-sensor-based maximum power point tracking system

International Nuclear Information System (INIS)

Park, Jae-Do; Lee, Hohyun; Bond, Matthew

2014-01-01

Highlights: • Feedforward MPPT scheme for uninterrupted TEG energy harvesting is suggested. • Temperature sensors are used to avoid current measurement or source disconnection. • MPP voltage reference is generated based on OCV vs. temperature differential model. • Optimal operating condition is maintained using hysteresis controller. • Any type of power converter can be used in the proposed scheme. - Abstract: In this paper, a thermoelectric generator (TEG) energy harvesting system with a temperature-sensor-based maximum power point tracking (MPPT) method is presented. Conventional MPPT algorithms for photovoltaic cells may not be suitable for thermoelectric power generation because a significant amount of time is required for TEG systems to reach a steady state. Moreover, complexity and additional power consumption in conventional circuits and periodic disconnection of power source are not desirable for low-power energy harvesting applications. The proposed system can track the varying maximum power point (MPP) with a simple and inexpensive temperature-sensor-based circuit without instantaneous power measurement or TEG disconnection. This system uses TEG’s open circuit voltage (OCV) characteristic with respect to temperature gradient to generate a proper reference voltage signal, i.e., half of the TEG’s OCV. The power converter controller maintains the TEG output voltage at the reference level so that the maximum power can be extracted for the given temperature condition. This feedforward MPPT scheme is inherently stable and can be implemented without any complex microcontroller circuit. The proposed system has been validated analytically and experimentally, and shows a maximum power tracking error of 1.15%

Achieving energy efficiency through product policy: the UK experience

International Nuclear Information System (INIS)

Boardman, Brenda

2004-01-01

The focus of this paper is on energy efficiency of domestic equipment. It is contended that, in the UK and--by extension--elsewhere. Government has to take the lead in defining low-energy standards for products. In the absence of policy, manufacturers do not recognize the need for carbon reductions in the equipment they design and consumers are unaware of the variation in energy performance in the product range. At present, neither market pull nor technology push can be relied upon to deliver energy savings. The imposition of a weak minimum standard on domestic fridges and freezers in 1999 will, over the lifetime of the appliances already sold by December 2002, save 1 Mt C of carbon dioxide at nil cost to government or to the manufacturers, and a net benefit to consumers of pound 855 m: a highly cost-effective policy. The difference between energy efficiency and energy conservation is that it takes time for the cumulative benefits of an energy efficiency improvement to result in the maximum effect on energy demand reduction: the benefits of the 1999 energy efficiency standard will accumulate until at least 2020. This period is equivalent to the cycle of stock replacement for that particular object. The final level of energy conservation depends upon the offsetting effects of growth in ownership levels and the size of new equipment purchases

Energy inputs for production of wheat in Pakistan

International Nuclear Information System (INIS)

Khan, M.A.

2002-01-01

The energetics of the wheat crop on rainfed farms have been worked out and compared with the farms having canal and tube well irrigation. A survey was conducted to investigate the pattern of energy used in production of wheat. The information was recorded from selected farms through biweekly visits. Results indicated that the farmers on bullock operated farms used more family labour than tractor operated farms, whereas, farmers on tractor operated farms used more casual labour. Bullocks were main source of power for all farms operations on bullock operated farms, however, threshing was performed with tractor driven threshers on almost all farms. Farmers on tube well irrigated farms used maximum energy to irrigate their crop.(author)

Optimization of PV-based energy production by dynamic PV-panel/inverter configuration

DEFF Research Database (Denmark)

Paasch, Kasper; Nymand, Morten; Haase, Frerk

This paper investigates the possible increase in annual energy production of a PV system with more than one MPPT (maximum power point tracker) input channels under Nordic illumination conditions, in case a concept of dynamic switching of the PV panels is used at the inputs of the inverters....

High-energy solar flare observations at the Y2K maximum

Science.gov (United States)

Emslie, A. Gordon

2000-04-01

Solar flares afford an opportunity to observe processes associated with the acceleration and propagation of high-energy particles at a level of detail not accessible in any other astrophysical source. I will review some key results from previous high-energy solar flare observations, including those from the Compton Gamma-Ray Observatory, and the problems that they pose for our understanding of energy release and particle acceleration processes in the astrophysical environment. I will then discuss a program of high-energy observations to be carried out during the upcoming 2000-2001 solar maximum that is aimed at addressing and resolving these issues. A key element in this observational program is the High Energy Solar Spectroscopic Imager (HESSI) spacecraft, which will provide imaging spectroscopic observations with spatial, temporal, and energy resolutions commensurate with the physical processes believed to be operating, and will in addition provide the first true gamma-ray spectroscopy of an astrophysical source. .

Maximum entropy production: Can it be used to constrain conceptual hydrological models?

Science.gov (United States)

M.C. Westhoff; E. Zehe

2013-01-01

In recent years, optimality principles have been proposed to constrain hydrological models. The principle of maximum entropy production (MEP) is one of the proposed principles and is subject of this study. It states that a steady state system is organized in such a way that entropy production is maximized. Although successful applications have been reported in...

Lower Bounds on the Maximum Energy Benefit of Network Coding for Wireless Multiple Unicast

Directory of Open Access Journals (Sweden)

Matsumoto Ryutaroh

2010-01-01

Full Text Available We consider the energy savings that can be obtained by employing network coding instead of plain routing in wireless multiple unicast problems. We establish lower bounds on the benefit of network coding, defined as the maximum of the ratio of the minimum energy required by routing and network coding solutions, where the maximum is over all configurations. It is shown that if coding and routing solutions are using the same transmission range, the benefit in d-dimensional networks is at least . Moreover, it is shown that if the transmission range can be optimized for routing and coding individually, the benefit in 2-dimensional networks is at least 3. Our results imply that codes following a decode-and-recombine strategy are not always optimal regarding energy efficiency.

Modelling the existing Irish energy-system to identify future energy costs and the maximum wind penetration feasible

DEFF Research Database (Denmark)

Connolly, D.; Lund, Henrik; Mathiesen, Brian Vad

2010-01-01

energy- system to future energy costs by considering future fuel prices, CO2 prices, and different interest rates. The final investigation identifies the maximum wind penetration feasible on the 2007 Irish energy- system from a technical and economic perspective, as wind is the most promising fluctuating...... for the existing Irish energy-system is approximately 30% from both a technical and economic perspective based on 2020 energy prices. Future studies will use the model developed in this study to show that higher wind penetrations can be achieved if the existing energy-system is modified correctly. Finally...... renewable resource available in Ireland. It is concluded that the reference model simulates the Irish energy-system accurately, the annual fuel costs for Ireland’s energy could increase by approximately 58% from 2007 to 2020 if a business-as-usual scenario is followed, and the optimum wind penetration...

An Integrated Approach to Water-Energy Nexus in Shale-Gas Production

Directory of Open Access Journals (Sweden)

Fadhil Y. Al-Aboosi

2018-05-01

Full Text Available Shale gas production is associated with significant usage of fresh water and discharge of wastewater. Consequently, there is a necessity to create proper management strategies for water resources in shale gas production and to integrate conventional energy sources (e.g., shale gas with renewables (e.g., solar energy. The objective of this study is to develop a design framework for integrating water and energy systems including multiple energy sources, the cogeneration process and desalination technologies in treating wastewater and providing fresh water for shale gas production. Solar energy is included to provide thermal power directly to a multi-effect distillation plant (MED exclusively (to be more feasible economically or indirect supply through a thermal energy storage system. Thus, MED is driven by direct or indirect solar energy and excess or direct cogeneration process heat. The proposed thermal energy storage along with the fossil fuel boiler will allow for the dual-purpose system to operate at steady-state by managing the dynamic variability of solar energy. Additionally, electric production is considered to supply a reverse osmosis plant (RO without connecting to the local electric grid. A multi-period mixed integer nonlinear program (MINLP is developed and applied to discretize the operation period to track the diurnal fluctuations of solar energy. The solution of the optimization program determines the optimal mix of solar energy, thermal storage and fossil fuel to attain the maximum annual profit of the entire system. A case study is solved for water treatment and energy management for Eagle Ford Basin in Texas.

Lower Bounds on the Maximum Energy Benefit of Network Coding for Wireless Multiple Unicast

NARCIS (Netherlands)

Goseling, J.; Matsumoto, R.; Uyematsu, T.; Weber, J.H.

2010-01-01

We consider the energy savings that can be obtained by employing network coding instead of plain routing in wireless multiple unicast problems. We establish lower bounds on the benefit of network coding, defined as the maximum of the ratio of the minimum energy required by routing and network coding

Lower bounds on the maximum energy benefit of network coding for wireless multiple unicast

NARCIS (Netherlands)

Goseling, Jasper; Matsumoto, Ryutaroh; Uyematsu, Tomohiko; Weber, Jos H.

2010-01-01

We consider the energy savings that can be obtained by employing network coding instead of plain routing in wireless multiple unicast problems. We establish lower bounds on the benefit of network coding, defined as the maximum of the ratio of the minimum energy required by routing and network coding

Maximum hardness and minimum polarizability principles through lattice energies of ionic compounds

International Nuclear Information System (INIS)

Kaya, Savaş; Kaya, Cemal; Islam, Nazmul

2016-01-01

The maximum hardness (MHP) and minimum polarizability (MPP) principles have been analyzed using the relationship among the lattice energies of ionic compounds with their electronegativities, chemical hardnesses and electrophilicities. Lattice energy, electronegativity, chemical hardness and electrophilicity values of ionic compounds considered in the present study have been calculated using new equations derived by some of the authors in recent years. For 4 simple reactions, the changes of the hardness (Δη), polarizability (Δα) and electrophilicity index (Δω) were calculated. It is shown that the maximum hardness principle is obeyed by all chemical reactions but minimum polarizability principles and minimum electrophilicity principle are not valid for all reactions. We also proposed simple methods to compute the percentage of ionic characters and inter nuclear distances of ionic compounds. Comparative studies with experimental sets of data reveal that the proposed methods of computation of the percentage of ionic characters and inter nuclear distances of ionic compounds are valid.

Maximum hardness and minimum polarizability principles through lattice energies of ionic compounds

Energy Technology Data Exchange (ETDEWEB)

Kaya, Savaş, E-mail: savaskaya@cumhuriyet.edu.tr [Department of Chemistry, Faculty of Science, Cumhuriyet University, Sivas 58140 (Turkey); Kaya, Cemal, E-mail: kaya@cumhuriyet.edu.tr [Department of Chemistry, Faculty of Science, Cumhuriyet University, Sivas 58140 (Turkey); Islam, Nazmul, E-mail: nazmul.islam786@gmail.com [Theoretical and Computational Chemistry Research Laboratory, Department of Basic Science and Humanities/Chemistry Techno Global-Balurghat, Balurghat, D. Dinajpur 733103 (India)

2016-03-15

The maximum hardness (MHP) and minimum polarizability (MPP) principles have been analyzed using the relationship among the lattice energies of ionic compounds with their electronegativities, chemical hardnesses and electrophilicities. Lattice energy, electronegativity, chemical hardness and electrophilicity values of ionic compounds considered in the present study have been calculated using new equations derived by some of the authors in recent years. For 4 simple reactions, the changes of the hardness (Δη), polarizability (Δα) and electrophilicity index (Δω) were calculated. It is shown that the maximum hardness principle is obeyed by all chemical reactions but minimum polarizability principles and minimum electrophilicity principle are not valid for all reactions. We also proposed simple methods to compute the percentage of ionic characters and inter nuclear distances of ionic compounds. Comparative studies with experimental sets of data reveal that the proposed methods of computation of the percentage of ionic characters and inter nuclear distances of ionic compounds are valid.

Maximum entropy production rate in quantum thermodynamics

Energy Technology Data Exchange (ETDEWEB)

Beretta, Gian Paolo, E-mail: beretta@ing.unibs.i [Universita di Brescia, via Branze 38, 25123 Brescia (Italy)

2010-06-01

In the framework of the recent quest for well-behaved nonlinear extensions of the traditional Schroedinger-von Neumann unitary dynamics that could provide fundamental explanations of recent experimental evidence of loss of quantum coherence at the microscopic level, a recent paper [Gheorghiu-Svirschevski 2001 Phys. Rev. A 63 054102] reproposes the nonlinear equation of motion proposed by the present author [see Beretta G P 1987 Found. Phys. 17 365 and references therein] for quantum (thermo)dynamics of a single isolated indivisible constituent system, such as a single particle, qubit, qudit, spin or atomic system, or a Bose-Einstein or Fermi-Dirac field. As already proved, such nonlinear dynamics entails a fundamental unifying microscopic proof and extension of Onsager's reciprocity and Callen's fluctuation-dissipation relations to all nonequilibrium states, close and far from thermodynamic equilibrium. In this paper we propose a brief but self-contained review of the main results already proved, including the explicit geometrical construction of the equation of motion from the steepest-entropy-ascent ansatz and its exact mathematical and conceptual equivalence with the maximal-entropy-generation variational-principle formulation presented in Gheorghiu-Svirschevski S 2001 Phys. Rev. A 63 022105. Moreover, we show how it can be extended to the case of a composite system to obtain the general form of the equation of motion, consistent with the demanding requirements of strong separability and of compatibility with general thermodynamics principles. The irreversible term in the equation of motion describes the spontaneous attraction of the state operator in the direction of steepest entropy ascent, thus implementing the maximum entropy production principle in quantum theory. The time rate at which the path of steepest entropy ascent is followed has so far been left unspecified. As a step towards the identification of such rate, here we propose a possible

Energy intensities of food products. Energie-intensiteiten van voedingsmiddelen

Energy Technology Data Exchange (ETDEWEB)

Kok, R.; Biesiot, W.; Wilting, H.C.

1993-08-01

The energy intensity of a product is the amount of primary energy used per Dutch guilder spent on consumer goods. The energy intensity can differ for each spending and varies from household to household. The aim of this study is to calculate the energy intensities and to provide an overview of the total package of consumer goods, including sociological categories and lifestyles, and the related use of primary energy to produce these goods. Use is made of the Energy Analysis Program (EAP) to calculate the energy intensities. EAP is based on the hybrid method: both the process analysis and the input-output analysis are applied in the model. The data input of the model consists of data from the Budget Survey 1990 of the Dutch Central Bureau of Statistics, which holds data of consumptions from 2767 households. In the chapters 4 to 10 energy intensities are given of the categories bread, pastry and groceries (chapter four), potatoes, vegetables and fruits (chapter five), sugary products and beverages (chapter six), oils and fats (chapter seven), meat, meat products and fish (chapter eight), dairy products (chapter nine), and other food products (chapter ten). The highest energy intensity is found for oils and fats (13.5 MJ per Dutch guilder). The energy intensities for the other products vary from 4.0 to 6.6 MJ/gld. It appears that most of the energy intensive products are products which do not use a large part of the primary energy, mainly because the consumption of these products is low. On the other hand many of the products that consume much of the primary energy (i.e. are consumed much themselves) are relatively energy extensive. The products that show a high consumption rate have relatively low energy intensities. Some of the options to shift towards a more energy extensive food package are the use of fresh products and outside grown products instead of treated products or greenhouse products and a more balanced diet. 5 figs., 18 tabs., 2 appendices, 52 refs.

Life cycle energy efficiency and environmental impact assessment of bioethanol production from sweet potato based on different production modes

Science.gov (United States)

Zhang, Jun; Jia, Chunrong; Wu, Yi; Xi, Beidou; Wang, Lijun; Zhai, Youlong

2017-01-01

The bioethanol is playing an increasingly important role in renewable energy in China. Based on the theory of circular economy, integration of different resources by polygeneration is one of the solutions to improve energy efficiency and to reduce environmental impact. In this study, three modes of bioethanol production were selected to evaluate the life cycle energy efficiency and environmental impact of sweet potato-based bioethanol. The results showed that, the net energy ratio was greater than 1 and the value of net energy gain was positive in the three production modes, in which the maximum value appeared in the circular economy mode (CEM). The environment emission mainly occurred to bioethanol conversion unit in the conventional production mode (CPM) and the cogeneration mode (CGM), and eutrophication potential (EP) and global warming potential (GWP) were the most significant environmental impact category. While compared with CPM and CGM, the environmental impact of CEM significantly declined due to increasing recycling, and plant cultivation unit mainly contributed to EP and GWP. And the comprehensive evaluation score of environmental impact decreased by 73.46% and 23.36%. This study showed that CEM was effective in improving energy efficiency, especially in reducing the environmental impact, and it provides a new method for bioethanol production. PMID:28672044

Evaluation of a photovoltaic energy mechatronics system with a built-in quadratic maximum power point tracking algorithm

Energy Technology Data Exchange (ETDEWEB)

Chao, R.M.; Ko, S.H.; Lin, I.H. [Department of Systems and Naval Mechatronics Engineering, National Cheng Kung University, Tainan, Taiwan 701 (China); Pai, F.S. [Department of Electronic Engineering, National University of Tainan (China); Chang, C.C. [Department of Environment and Energy, National University of Tainan (China)

2009-12-15

The historically high cost of crude oil price is stimulating research into solar (green) energy as an alternative energy source. In general, applications with large solar energy output require a maximum power point tracking (MPPT) algorithm to optimize the power generated by the photovoltaic effect. This work aims to provide a stand-alone solution for solar energy applications by integrating a DC/DC buck converter to a newly developed quadratic MPPT algorithm along with its appropriate software and hardware. The quadratic MPPT method utilizes three previously used duty cycles with their corresponding power outputs. It approaches the maximum value by using a second order polynomial formula, which converges faster than the existing MPPT algorithm. The hardware implementation takes advantage of the real-time controller system from National Instruments, USA. Experimental results have shown that the proposed solar mechatronics system can correctly and effectively track the maximum power point without any difficulties. (author)

Maximum Energy Yield Oriented Turbine Control in PMSG based Wind Farm

DEFF Research Database (Denmark)

Tian, Jie; Zhou, Dao; Su, Chi

2017-01-01

: In the modern power systems, with the fast integration of the wind power into the grid, it turns to develop large-scale offshore wind farms equipped with the permanent magnet synchronous generator (PMSG) wind turbine. In large-scale offshore wind farms, the wind turbine operating reliability...... and the wake effect in the wind farm became important issues. The pitch angle and tip speed ratio are the two degrees of freedom for the PMSG wind turbine active power control, which are also the determining factors of the wind turbine lifetime. As the energy production of the wind turbine is the product...... of its active power and lifetime, the energy production can be maximised by optimising its pitch angle and tip speed ratio. In this study, the energy production of a 2 MW PMSG wind turbine is maximised by optimising its pitch angle and tip speed ratio. Moreover, taking into account the wake effect...

Information Entropy Production of Maximum Entropy Markov Chains from Spike Trains

Directory of Open Access Journals (Sweden)

Rodrigo Cofré

2018-01-01

Full Text Available The spiking activity of neuronal networks follows laws that are not time-reversal symmetric; the notion of pre-synaptic and post-synaptic neurons, stimulus correlations and noise correlations have a clear time order. Therefore, a biologically realistic statistical model for the spiking activity should be able to capture some degree of time irreversibility. We use the thermodynamic formalism to build a framework in the context maximum entropy models to quantify the degree of time irreversibility, providing an explicit formula for the information entropy production of the inferred maximum entropy Markov chain. We provide examples to illustrate our results and discuss the importance of time irreversibility for modeling the spike train statistics.

Climate-simulated raceway pond culturing: quantifying the maximum achievable annual biomass productivity of Chlorella sorokiniana in the contiguous USA

Energy Technology Data Exchange (ETDEWEB)

Huesemann, M.; Chavis, A.; Edmundson, S.; Rye, D.; Hobbs, S.; Sun, N.; Wigmosta, M.

2017-09-13

Chlorella sorokiniana (DOE 1412) emerged as one of the most promising microalgae strains from the NAABB consortium project, with a remarkable doubling time under optimal conditions of 2.57 hr-1. However, its maximum achievable annual biomass productivity in outdoor ponds in the contiguous United States remained unknown. In order to address this knowledge gap, this alga was cultured in indoor LED-lighted and temperature-controlled raceways in nutrient replete freshwater (BG-11) medium at pH 7 under conditions simulating the daily sunlight intensity and water temperature fluctuations during three seasons in Southern Florida, an optimal outdoor pond culture location for this organism identified by biomass growth modeling. Prior strain characterization indicated that the average maximum specific growth rate (µmax) at 36 ºC declined continuously with pH, with µmax corresponding to 5.92, 5.83, 4.89, and 4.21 day-1 at pH 6, 7, 8, and 9, respectively. In addition, the maximum specific growth rate declined nearly linearly with increasing salinity until no growth was observed above 35 g/L NaCl. In the climate-simulated culturing studies, the volumetric ash-free dry weight-based biomass productivities during the linear growth phase were 57, 69, and 97 mg/L-day for 30-year average light and temperature simulations for January (winter), March (spring), and July (summer), respectively, which corresponds to average areal productivities of 11.6, 14.1, and 19.9 g/m2-day at a constant pond depth of 20.5 cm. The photosynthetic efficiencies (PAR) in the three climate-simulated pond culturing experiments ranged from 4.1 to 5.1%. The annual biomass productivity was estimated as ca. 15 g/m2-day, nearly double the U.S. Department of Energy (DOE) 2015 State of Technology annual cultivation productivity of 8.5 g/m2-day, but this is still significantly below the projected 2022 target of ca. 25 g/m2-day (U.S. DOE, 2016) for economic microalgal biofuel production, indicating the need for

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.

The maximum energy of cosmic rays gained in the jet of black holes

International Nuclear Information System (INIS)

Tascau, Oana; Biermann, Peter

2003-01-01

In this paper we will present the results of the calculation of maximum energy gained by a particle in the acceleration process done by the black hole mechanism. We are using here the model of P. Biermann and H. Falcke to determine if and how the black holes contribute to the cosmic rays that reach the Earth. The conclusion is that at the highest energy only M87 contributes, as has been claimed for many years. Secondly, at lower energy, Cen A may indeed take over as second most important source, again as expected for some time. (authors)

Subsumed complexity: abiogenesis as a by-product of complex energy transduction

Science.gov (United States)

Adam, Z. R.; Zubarev, D.; Aono, M.; Cleaves, H. James

2017-11-01

The origins of life bring into stark relief the inadequacy of our current synthesis of thermodynamic, chemical, physical and information theory to predict the conditions under which complex, living states of organic matter can arise. Origins research has traditionally proceeded under an array of implicit or explicit guiding principles in lieu of a universal formalism for abiogenesis. Within the framework of a new guiding principle for prebiotic chemistry called subsumed complexity, organic compounds are viewed as by-products of energy transduction phenomena at different scales (subatomic, atomic, molecular and polymeric) that retain energy in the form of bonds that inhibit energy from reaching the ground state. There is evidence for an emergent level of complexity that is overlooked in most conceptualizations of abiogenesis that arises from populations of compounds formed from atomic energy input. We posit that different forms of energy input can exhibit different degrees of dissipation complexity within an identical chemical medium. By extension, the maximum capacity for organic chemical complexification across molecular and macromolecular scales subsumes, rather than emerges from, the underlying complexity of energy transduction processes that drive their production and modification. This article is part of the themed issue 'Reconceptualizing the origins of life'.

Research on Energy-Saving Production Scheduling Based on a Clustering Algorithm for a Forging Enterprise

Directory of Open Access Journals (Sweden)

Yifei Tong

2016-02-01

Full Text Available Energy efficiency is a buzzword of the 21st century. With the ever growing need for energy efficient and low-carbon production, it is a big challenge for high energy-consumption enterprises to reduce their energy consumption. To this aim, a forging enterprise, DVR (the abbreviation of a forging enterprise, is researched. Firstly, an investigation into the production processes of DVR is given as well as an analysis of forging production. Then, the energy-saving forging scheduling is decomposed into two sub-problems. One is for cutting and machining scheduling, which is similar to traditional machining scheduling. The other one is for forging and heat treatment scheduling. Thirdly, former forging production scheduling is presented and solved based on an improved genetic algorithm. Fourthly, the latter is discussed in detail, followed by proposed dynamic clustering and stacking combination optimization. The proposed stacking optimization requires making the gross weight of forgings as close to the maximum batch capacity as possible. The above research can help reduce the heating times, and increase furnace utilization with high energy efficiency and low carbon emissions.

A field study of energy consumption in wheat production in Canterbury, New Zealand

International Nuclear Information System (INIS)

Safa, M.; Samarasinghe, S.; Mohssen, M.

2011-01-01

Research highlights: → We determine the energy use in wheat production base on farm operation and energy sources on dryland and irrigated farms in New Zealand. → The study estimate and compare different energy inputs in wheat production using around 40 samples. → The results show fertilizer is the most important energy inputs on farms. → The significant correlation between energy use and wheat production must be taken into consideration. -- Abstract: This paper examines the energy consumption of wheat production in Canterbury province, New Zealand. This study was conducted within a 35,300 ha of irrigated and dry land wheat fields in Canterbury in the 2007-2008 harvest year. Total energy consumption for wheat production was estimated at 25,600 MJ/ha. On average, fertilizer and electricity were used more than other energy sources, at around 10,654 (47%) and 4870 (22%) MJ/ha, respectively. The energy consumption for wheat in irrigated farming systems and dry land farming systems was estimated at 25,600 and 17,458 MJ/ha, respectively. The main source of energy in both systems is fertilizer and it consumed around 10,188 and 11,429 MJ/ha for irrigated farming and dry land farming, respectively. The average operational energy consumption was 7997 MJ/ha. In irrigated farming system, operational energy was approximately three times more than that in dry land farming. The maximum energy consumed in operational wheat production was about 7762 (71%) MJ/ha for irrigated farming systems, including irrigation, and it was 1451 (46%) MJ/ha for dry land farming including tillage. The average values of estimated output to input energy ratio for wheat in irrigated and dry land farming systems were 11.5 and 15.1, respectively.

Quantifying biomass production in crops grown for energy

Energy Technology Data Exchange (ETDEWEB)

Bullard, M J; Christian, D; Wilkins, C

1997-12-31

One estimate suggests that continued CAP (Common Agricultural Policy) reform may lead to as much as 2 million hectares of land set aside from arable production by the year 2020 in the UK alone, with 20 million hectares in the EU in total. Set-aside currently occupies more than 500,000 hectares in the UK. Set-aside land is providing more opportunities for non-food crops, for example fuel crops, which provide biomass for energy. Whilst any crop species will produce biomass which can be burnt to produce energy, arable crops were not developed with this in mind but rather a specific harvestable commodity, e.g. grain, and therefore the total harvestable commodity is seldom maximised. The characteristics of an ideal fuel crop have been identified as: dry harvested material for efficient combustion; perennial growth to minimise establishment costs and lengthen the growing season; good disease resistance; efficient conversion of solar radiation to biomass energy; efficient use of nitrogen fertiliser (where required) and water; and yield close to the theoretical maximum. Miscanthus, a genus of Oriental and African C4 perennial grasses, has been identified as possessing the above characteristics. There may be other species, which, if not yielding quite as much biomass, have other characteristics of merit. This has led to the need to identify inherently productive species which are adapted to the UK, and to validate the productivity of species which have already been 'discovered'. (author)

Quantifying biomass production in crops grown for energy

Energy Technology Data Exchange (ETDEWEB)

Bullard, M.J.; Christian, D.; Wilkins, C.

1996-12-31

One estimate suggests that continued CAP (Common Agricultural Policy) reform may lead to as much as 2 million hectares of land set aside from arable production by the year 2020 in the UK alone, with 20 million hectares in the EU in total. Set-aside currently occupies more than 500,000 hectares in the UK. Set-aside land is providing more opportunities for non-food crops, for example fuel crops, which provide biomass for energy. Whilst any crop species will produce biomass which can be burnt to produce energy, arable crops were not developed with this in mind but rather a specific harvestable commodity, e.g. grain, and therefore the total harvestable commodity is seldom maximised. The characteristics of an ideal fuel crop have been identified as: dry harvested material for efficient combustion; perennial growth to minimise establishment costs and lengthen the growing season; good disease resistance; efficient conversion of solar radiation to biomass energy; efficient use of nitrogen fertiliser (where required) and water; and yield close to the theoretical maximum. Miscanthus, a genus of Oriental and African C4 perennial grasses, has been identified as possessing the above characteristics. There may be other species, which, if not yielding quite as much biomass, have other characteristics of merit. This has led to the need to identify inherently productive species which are adapted to the UK, and to validate the productivity of species which have already been 'discovered'. (author)

Present status of research on hydrogen energy and perspective of HTGR hydrogen production system

Energy Technology Data Exchange (ETDEWEB)

Miyamoto, Yoshiaki; Ogawa, Masuro; Akino, Norio [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment] [and others

2001-03-01

A study was performed to make a clear positioning of research and development on hydrogen production systems with a High Temperature Gas-cooled Reactor (HTGR) under currently promoting at the Japan Atomic Energy Research Institute through a grasp of the present status of hydrogen energy, focussing on its production and utilization as an energy in future. The study made clear that introduction of safe distance concept for hydrogen fire and explosion was practicable for a HTGR hydrogen production system, including hydrogen properties and need to provide regulations applying to handle hydrogen. And also generalization of hydrogen production processes showed technical issues of the HTGR system. Hydrogen with HTGR was competitive to one with fossil fired system due to evaluation of production cost. Hydrogen is expected to be used as promising fuel of fuel cell cars in future. In addition, the study indicated that there were a large amount of energy demand alternative to high efficiency power generation and fossil fuel with nuclear energy through the structure of energy demand and supply in Japan. Assuming that hydrogen with HTGR meets all demand of fuel cell cars, an estimation would show introduction of the maximum number of about 30 HTGRs with capacity of 100 MWt from 2020 to 2030. (author)

Energy ratios in Finnish agricultural production

Directory of Open Access Journals (Sweden)

H. J. MIKKOLA

2008-12-01

Full Text Available The objective of this study was to assess energy ratios and net energy in plant production and energy ratios in animal production in Finland. Energy ratios and net energy were determined on the basis of plant- and animal-specific energy analyses. In plant production, energy ratios and net energy were assessed as a function of nitrogen fertilization, because indirect energy input in the form of agrochemicals was 54—73% from the total energy input and nitrogen was responsible for the major part of this. The highest energy ratio was 18.6 for reed canary grass. As a whole reed canary grass was superior to the other crops, which were barley, spring wheat, spring turnip rape, ley for silage, potato and sugar beet. Reed canary grass and sugar beet gained the highest net energy yields of 111–115 GJ ha-1. The optimum energy ratio was gained in general with less nitrogen fertilization intensity than farmers use. The energy ratios in pork production varied between 0.14–1.28 depending on what was included or excluded in the analysis and for milk production between 0.15–1.85. Ratios of 1.28 in pork production and 1.85 in milk production are unrealistic as they do not give any shelter to the animals, although they can be approached in very low-input production systems. If the ratio is calculated with feed energy content then the ratio is low, 0.14–0.22 for pork and 0.15 for milk. This shows that animals can convert 14–22 percent of the input energy to usable products. In pork production, the largest portion of the energy input was the ventilation of the building. In milk production milking and cooling consumes a lot of energy and for this reason the electricity consumption is high.;

Maximum power gains of radio-frequency-driven two-energy-component tokamak reactors

International Nuclear Information System (INIS)

Jassby, D.L.

1974-11-01

Two-energy-component fusion reactors in which the suprathermal component (D) is produced by harmonic cyclotron ''runaway'' of resonant ions are considered. In one ideal case, the fast hydromagnetic wave at ω = 2ω/sub cD/ produces an energy distribution f(W) approximately constant (up to W/sub max/) that includes all deuterons, which then thermalize and react with the cold tritons. In another ideal case, f(W) approximately constant is maintained by the fast wave at ω = ω/sub cD/. If one neglects (1) direct rf input to the bulk-plasma electrons and tritons, and (2) the fact that many deuterons are not resonantly accelerated, then the maximum ideal power gain is about 0.85 Q/sub m/ in the first case and 1.05 Q/sub m/ in the second case, where Q/sub m/ is the maximum fusion gain in the beam-injection scheme (e.g., Q/sub m/ = 1.9 at T/sub e/ = 10 keV). Because of nonideal effects, the cyclotron runaway phenomenon may find its most practical use in the heating of 50:50 D--T plasmas to ignition. (auth)

Wavestar Energy Production Outlook

DEFF Research Database (Denmark)

Frigaard, Peter Bak; Andersen, Thomas Lykke; Kofoed, Jens Peter

It is of paramount importance to decrease the Cost of Energy (CoE) from Wavestar wave energy con-verters (WECs) in order to make the WECs competitive to other sources of renewable energy. The CoE can be decreased by reducing the cost of the machines (CAPEX and OPEX) and by increasing the in......-come. The income can most obviously be enlarged by increasing the energy production. The focus of the present note is solely on expectations to the yearly energy production from future Wavestar WECs....

Multi-digit maximum voluntary torque production on a circular object

Science.gov (United States)

SHIM, JAE KUN; HUANG, JUNFENG; HOOKE, ALEXANDER W.; LATSH, MARK L.; ZATSIORSKY, VLADIMIR M.

2010-01-01

Individual digit-tip forces and moments during torque production on a mechanically fixed circular object were studied. During the experiments, subjects positioned each digit on a 6-dimensional force/moment sensor attached to a circular handle and produced a maximum voluntary torque on the handle. The torque direction and the orientation of the torque axis were varied. From this study, it is concluded that: (1) the maximum torque in the closing (clockwise) direction was larger than in the opening (counter clockwise) direction; (2) the thumb and little finger had the largest and the smallest share of both total normal force and total moment, respectively; (3) the sharing of total moment between individual digits was not affected by the orientation of the torque axis or by the torque direction, while the sharing of total normal force between the individual digit varied with torque direction; (4) the normal force safety margins were largest and smallest in the thumb and little finger, respectively. PMID:17454086

Modelling the existing Irish energy-system to identify future energy costs and the maximum wind penetration feasible

International Nuclear Information System (INIS)

Connolly, D.; Leahy, M.; Lund, H.; Mathiesen, B.V.

2010-01-01

In this study a model of the Irish energy-system was developed using EnergyPLAN based on the year 2007, which was then used for three investigations. The first compares the model results with actual values from 2007 to validate its accuracy. The second illustrates the exposure of the existing Irish energy-system to future energy costs by considering future fuel prices, CO 2 prices, and different interest rates. The final investigation identifies the maximum wind penetration feasible on the 2007 Irish energy-system from a technical and economic perspective, as wind is the most promising fluctuating renewable resource available in Ireland. It is concluded that the reference model simulates the Irish energy-system accurately, the annual fuel costs for Ireland's energy could increase by approximately 58% from 2007 to 2020 if a business-as-usual scenario is followed, and the optimum wind penetration for the existing Irish energy-system is approximately 30% from both a technical and economic perspective based on 2020 energy prices. Future studies will use the model developed in this study to show that higher wind penetrations can be achieved if the existing energy-system is modified correctly. Finally, these results are not only applicable to Ireland, but also represent the issues facing many other countries. (author)

Existence and uniqueness of the maximum likelihood estimator for models with a Kronecker product covariance structure

NARCIS (Netherlands)

Ros, B.P.; Bijma, F.; de Munck, J.C.; de Gunst, M.C.M.

2016-01-01

This paper deals with multivariate Gaussian models for which the covariance matrix is a Kronecker product of two matrices. We consider maximum likelihood estimation of the model parameters, in particular of the covariance matrix. There is no explicit expression for the maximum likelihood estimator

Energy production systems engineering

CERN Document Server

Blair, Thomas Howard

2017-01-01

Energy Production Systems Engineering presents IEEE, Electrical Apparatus Service Association (EASA), and International Electrotechnical Commission (IEC) standards of engineering systems and equipment in utility electric generation stations. Electrical engineers that practice in the energy industry must understand the specific characteristics of electrical and mechanical equipment commonly applied to energy production and conversion processes, including the mechanical and chemical processes involved, in order to design, operate and maintain electrical systems that support and enable these processes. To aid this understanding, Energy Production Systems Engineeringdescribes the equipment and systems found in various types of utility electric generation stations. This information is accompanied by examples and practice problems. It also addresses common issues of electrical safety that arise in electric generation stations.

A novel algorithm for single-axis maximum power generation sun trackers

International Nuclear Information System (INIS)

Lee, Kung-Yen; Chung, Chi-Yao; Huang, Bin-Juine; Kuo, Ting-Jung; Yang, Huang-Wei; Cheng, Hung-Yen; Hsu, Po-Chien; Li, Kang

2017-01-01

Highlights: • A novel algorithm for a single-axis sun tracker is developed to increase the efficiency. • Photovoltaic module is rotated to find the optimal angle for generating the maximum power. • Electric energy increases up to 8.3%, compared with that of the tracker with three fixed angles. • The rotation range is optimized to reduce energy consumption from the rotation operations. - Abstract: The purpose of this study is to develop a novel algorithm for a single-axis maximum power generation sun tracker in order to identify the optimal stopping angle for generating the maximum amount of daily electric energy. First, the photovoltaic modules of the single-axis maximum power generation sun tracker are automatically rotated from 50° east to 50° west. During the rotation, the instantaneous power generated at different angles is recorded and compared, meaning that the optimal angle for generating the maximum power can be determined. Once the rotation (detection) is completed, the photovoltaic modules are then rotated to the resulting angle for generating the maximum power. The photovoltaic module is rotated once per hour in an attempt to detect the maximum irradiation and overcome the impact of environmental effects such as shading from cloud cover, other photovoltaic modules and surrounding buildings. Furthermore, the detection range is halved so as to reduce the energy consumption from the rotation operations and to improve the reliability of the sun tracker. The results indicate that electric energy production is increased by 3.4% in spring and autumn, 5.4% in summer, and 8.3% in winter, compared with that of the same sun tracker with three fixed angles of 50° east in the morning, 0° at noon and 50° west in the afternoon.

Concerning the maximum energy of ions accelerated at the front of a relativistic electron cloud expanding into vacuum

International Nuclear Information System (INIS)

Bulanov, S.V.; Esirkepov, T.Zh.; Koga, J.; Tajima, T.; Farina, D.

2004-01-01

Results of particle-in-cell simulations are presented that demonstrate characteristic interaction regimes of high-power laser radiation with plasma. It is shown that the maximum energy of fast ions can substantially exceed the electron energy. A theoretical model is proposed of ion acceleration at the front of a relativistic electron cloud expanding into vacuum in the regime of strong charge separation. The model describes the electric field structure and the dynamics of fast ions inside the electron cloud. The maximum energy the ions can gain at the front of the expanding electron cloud is found

Optimal operating conditions for maximum biogas production in anaerobic bioreactors

International Nuclear Information System (INIS)

Balmant, W.; Oliveira, B.H.; Mitchell, D.A.; Vargas, J.V.C.; Ordonez, J.C.

2014-01-01

The objective of this paper is to demonstrate the existence of optimal residence time and substrate inlet mass flow rate for maximum methane production through numerical simulations performed with a general transient mathematical model of an anaerobic biodigester introduced in this study. It is herein suggested a simplified model with only the most important reaction steps which are carried out by a single type of microorganisms following Monod kinetics. The mathematical model was developed for a well mixed reactor (CSTR – Continuous Stirred-Tank Reactor), considering three main reaction steps: acidogenesis, with a μ max of 8.64 day −1 and a K S of 250 mg/L, acetogenesis, with a μ max of 2.64 day −1 and a K S of 32 mg/L, and methanogenesis, with a μ max of 1.392 day −1 and a K S of 100 mg/L. The yield coefficients were 0.1-g-dry-cells/g-pollymeric compound for acidogenesis, 0.1-g-dry-cells/g-propionic acid and 0.1-g-dry-cells/g-butyric acid for acetogenesis and 0.1 g-dry-cells/g-acetic acid for methanogenesis. The model describes both the transient and the steady-state regime for several different biodigester design and operating conditions. After model experimental validation, a parametric analysis was performed. It was found that biogas production is strongly dependent on the input polymeric substrate and fermentable monomer concentrations, but fairly independent of the input propionic, acetic and butyric acid concentrations. An optimisation study was then conducted and optimal residence time and substrate inlet mass flow rate were found for maximum methane production. The optima found were very sharp, showing a sudden drop of methane mass flow rate variation from the observed maximum to zero, within a 20% range around the optimal operating parameters, which stresses the importance of their identification, no matter how complex the actual bioreactor design may be. The model is therefore expected to be a useful tool for simulation, design, control and

Production of bio-energies

International Nuclear Information System (INIS)

Gurtler, J.L.; Femenias, A.; Blondy, J.

2009-01-01

After having indicated the various possible origins of biomass, this paper considers the issue of bio-energies, i.e., energies produced with biomass related to forest or agriculture production. Some indicators are defined (share of renewable energies, share of biomass in the energy production and consumption, number of production units). Stake holders are identified. Then, major and emerging trends are identified and discussed. The major trends are: development and diversification of renewable energies, development of bio-fuels with the support of incentive policies, prevalence of the wood-energy sector on the whole renewable energies, increase of surfaces dedicated to bio-fuels since the end of the 1990's, a French biogas sector which is late with respect to other countries. The emerging trends are: the important role of oil price in the development of bio-fuels, a necessary public support for the development of biogas, mobilization of research and development of competitiveness poles for bio-industries. Some prospective issues are also discussed in terms of uncertainties (soil availabilities, environmental performance of bio-fuels, available biomass resource, need of a technological advance, and evolution of energy needs on a medium term, tax and public policy). Three hypotheses of bio-energy evolutions are discussed

Maximum Power from a Solar Panel

Directory of Open Access Journals (Sweden)

Michael Miller

2010-01-01

Full Text Available Solar energy has become a promising alternative to conventional fossil fuel sources. Solar panels are used to collect solar radiation and convert it into electricity. One of the techniques used to maximize the effectiveness of this energy alternative is to maximize the power output of the solar collector. In this project the maximum power is calculated by determining the voltage and the current of maximum power. These quantities are determined by finding the maximum value for the equation for power using differentiation. After the maximum values are found for each time of day, each individual quantity, voltage of maximum power, current of maximum power, and maximum power is plotted as a function of the time of day.

Flux and energy dependence of methane production from graphite due to H+ impact

International Nuclear Information System (INIS)

Davis, J.W.; Haasz, A.A.; Stangeby, P.C.

1986-06-01

Carbon is in widespread use for limiter surfaces, as well as first wall coatings in current tokamaks. Chemical erosion via methane formation, due to energetic H + impact, is expected to contribute to the total erosion rate of carbon from these surfaces. Experimental results are presented for the methane yield from pyrolytic graphite due to H + exposure, using a mass analyzed ion beam. H + energies of 0.1-3 keV and flux densities of ∼ 5x10 13 to l0 16 H + /cm 2 s were used. The measured methane yield (CH 4 /H + ) initially increases with flux density, then reaches a maximum, which is followed by a gradual decrease. The magnitude of the maximum yield and the flux density at which it occurs depends on the graphite temperature. The yields obtained at temperatures corresponding to yield maxima at specific flux densities also show an initial increase, followed by a shallow maximum and a gradual decrease as a function of flux density; the maximum occurs at ∼10 15 H + /cm 2 s. Also presented are results on the methane production dependence on ion energy over the range 0.1 to 3 keV, and graphite temperature dependence measurements

Maximum power point tracking: a cost saving necessity in solar energy systems

Energy Technology Data Exchange (ETDEWEB)

Enslin, J H.R. [Stellenbosch Univ. (South Africa). Dept. of Electrical and Electronic Engineering

1992-12-01

A well engineered renewable remote energy system, utilizing the principal of Maximum Power Point Tracking (MPPT) can improve cost effectiveness, has a higher reliability and can improve the quality of life in remote areas. A high-efficient power electronic converter, for converting the output voltage of a solar panel, or wind generator, to the required DC battery bus voltage has been realized. The converter is controlled to track the maximum power point of the input source under varying input and output parameters. Maximum power point tracking for relative small systems is achieved by maximization of the output current in a battery charging regulator, using an optimized hill-climbing, inexpensive microprocessor based algorithm. Through practical field measurements it is shown that a minimum input source saving of between 15 and 25% on 3-5 kWh/day systems can easily be achieved. A total cost saving of at least 10-15% on the capital cost of these systems are achievable for relative small rating Remote Area Power Supply (RAPS) systems. The advantages at large temperature variations and high power rated systems are much higher. Other advantages include optimal sizing and system monitor and control. (author).

The unintended energy impacts of increased nitrate contamination from biofuels production.

Science.gov (United States)

Twomey, Kelly M; Stillwell, Ashlynn S; Webber, Michael E

2010-01-01

Increases in corn cultivation for biofuels production, due to the Energy Independence and Security Act of 2007, are likely to lead to increases in nitrate concentrations in both surface and groundwater resources in the United States. These increases might trigger the requirement for additional energy consumption for water treatment to remove the nitrates. While these increasing concentrations of nitrate might pose a human health concern, most water resources were found to be within current maximum contaminant level (MCL) limits of 10 mg L(-1) NO(3)-N. When water resources exceed this MCL, energy-intensive drinking water treatment is required to reduce nitrate levels below 10 mg L(-1). Based on prior estimates of water supplies currently exceeding the nitrate MCL, we calculate that advanced drinking water treatment might require an additional 2360 million kWh annually (for nitrate affected areas only)--a 2100% increase in energy requirements for water treatment in those same areas--to mitigate nitrate contamination and meet the MCL requirement. We predict that projected increases in nitrate contamination in water may impact the energy consumed in the water treatment sector, because of the convergence of several related trends: (1) increasing cornstarch-based ethanol production, (2) increasing nutrient loading in surface water and groundwater resources as a consequence of increased corn-based ethanol production, (3) additional drinking water sources that exceed the MCL for nitrate, and (4) potentially more stringent drinking water standards for nitrate.

Determination of the wind power systems load to achieve operation in the maximum energy area

Science.gov (United States)

Chioncel, C. P.; Tirian, G. O.; Spunei, E.; Gillich, N.

2018-01-01

This paper analyses the operation of the wind turbine, WT, in the maximum power point, MPP, by linking the load of the Permanent Magnet Synchronous Generator, PMSG, with the wind speed value. The load control methods at wind power systems aiming an optimum performance in terms of energy are based on the fact that the energy captured by the wind turbine significantly depends on the mechanical angular speed of the wind turbine. The presented control method consists in determining the optimal mechanical angular speed, ωOPTIM, using an auxiliary low power wind turbine, WTAUX, operating without load, at maximum angular velocity, ωMAX. The method relies on the fact that the ratio ωOPTIM/ωMAX has a constant value for a given wind turbine and does not depend on the time variation of the wind speed values.

Novel high efficient speed sensorless controller for maximum power extraction from wind energy conversion systems

International Nuclear Information System (INIS)

Fathabadi, Hassan

2016-01-01

Highlights: • Novel sensorless MPPT technique without drawbacks of other sensor/sensorless methods. • Tracking the actual MPP of WECSs, no tracking the MPP of their wind turbines. • Actually extracting the highest output power from WECSs. • Novel MPPT technique having the MPPT efficiency more than 98.5% for WECSs. • Novel MPPT technique having short convergence time for WECSs. - Abstract: In this study, a novel high accurate sensorless maximum power point tracking (MPPT) method is proposed. The technique tracks the actual maximum power point of a wind energy conversion system (WECS) at which maximum output power is extracted from the system, not the maximum power point of its wind turbine at which maximum mechanical power is obtained from the turbine, so it actually extracts the highest output power from the system. The technique only uses input voltage and current of the converter used in the system, and neither needs any speed sensors (anemometer and tachometer) nor has the drawbacks of other sensor/sensorless based MPPT methods. The technique has been implemented as a MPPT controller by constructing a WECS. Theoretical results, the technique performance, and its advantages are validated by presenting real experimental results. The real static-dynamic response of the MPPT controller is experimentally obtained that verifies the proposed MPPT technique high accurately extracts the highest instant power from wind energy conversion systems with the MPPT efficiency of more than 98.5% and a short convergence time that is only 25 s for the constructed system having a total inertia and friction coefficient of 3.93 kg m 2 and 0.014 N m s, respectively.

Application of the maximum entropy production principle to electrical systems

International Nuclear Information System (INIS)

Christen, Thomas

2006-01-01

For a simple class of electrical systems, the principle of the maximum entropy production rate (MaxEP) is discussed. First, we compare the MaxEP principle and the principle of the minimum entropy production rate and illustrate the superiority of the MaxEP principle for the example of two parallel constant resistors. Secondly, we show that the Steenbeck principle for the electric arc as well as the ohmic contact behaviour of space-charge limited conductors follow from the MaxEP principle. In line with work by Dewar, the investigations seem to suggest that the MaxEP principle can also be applied to systems far from equilibrium, provided appropriate information is available that enters the constraints of the optimization problem. Finally, we apply the MaxEP principle to a mesoscopic system and show that the universal conductance quantum, e 2 /h, of a one-dimensional ballistic conductor can be estimated

Factors that promote renewable energy production in U.S. states: A fixed effect estimation

Science.gov (United States)

Nwokeji, Ekwuniru Chika

2011-12-01

also affect renewable energy production. It therefore appears that to obtain a maximum renewable energy production, policymakers need to adopt a policy approach that incorporates these contextual factors.

Sectoral Energy, and Labour, Productivity Convergence

International Nuclear Information System (INIS)

Mulder, P.; De Groot, H.L.F.

2007-01-01

This paper empirically investigates the development of cross-country differences in energy- and labour productivity. The analysis is performed at a detailed sectoral level for 14 OECD countries, covering the period 1970-1997. A ρ-convergence analysis reveals that the development over time of the cross-country variation in productivity performance differs across sectors as well as across different levels of aggregation. Both patterns of convergence as well as divergence are found. Cross-country variation of productivity levels is typically larger for energy than for labour. A β-convergence analysis provides support for the hypothesis that in most sectors lagging countries tend to catch up with technological leaders, in particular in terms of energy productivity. Moreover, the results show that convergence is conditional, meaning that productivity levels converge to country-specific steady states. Energy prices and wages are shown to positively affect energy- and labour-productivity growth, respectively. We also find evidence for the importance of economies of scale, whereas the investment share, openness and specialization play only a modest role in explaining cross-country variation in energy- and labour-productivity growth

Material and energy productivity.

Science.gov (United States)

Steinberger, Julia K; Krausmann, Fridolin

2011-02-15

Resource productivity, measured as GDP output per resource input, is a widespread sustainability indicator combining economic and environmental information. Resource productivity is ubiquitous, from the IPAT identity to the analysis of dematerialization trends and policy goals. High resource productivity is interpreted as the sign of a resource-efficient, and hence more sustainable, economy. Its inverse, resource intensity (resource per GDP) has the reverse behavior, with higher values indicating environmentally inefficient economies. In this study, we investigate the global systematic relationship between material, energy and carbon productivities, and economic activity. We demonstrate that different types of materials and energy exhibit fundamentally different behaviors, depending on their international income elasticities of consumption. Biomass is completely inelastic, whereas fossil fuels tend to scale proportionally with income. Total materials or energy, as aggregates, have intermediate behavior, depending on the share of fossil fuels and other elastic resources. We show that a small inelastic share is sufficient for the total resource productivity to be significantly correlated with income. Our analysis calls into question the interpretation of resource productivity as a sustainability indicator. We conclude with suggestions for potential alternatives.

Environmental considerations in energy crop production

International Nuclear Information System (INIS)

Ranney, J.W.; Mann, L.K.

1994-01-01

This paper is a preliminary attempt to provide information on the probable environmental effects of energy crop production relative to other potential uses of the land. While dedicated energy crop production is anticipated to occur primarily on land currently in agricultural production, some pastureland and forestland with a high potential for conversion to agricultural production may be utilized. Experimental results suggest that chemical use on energy crops will be lower than on most row crops and that land producing energy crops should experience less erosion than land producing row crops. Long-term site productivity should not be a major issue if macro-and micro-fertilizers are added as needed and nutrient-conserving production techniques are used. (Author)

Simulations of the energy loss of ions at the stopping-power maximum in a laser-induced plasma

International Nuclear Information System (INIS)

Cayzac, W.; Malka, G.; Frank, A.; Bagnoud, V.; Blažević, A.; Schlegel, T.; Ortner, A.; Bedacht, S.; Deppert, O.; Knetsch, A.; Schaumann, G.; Wagner, F.; Basko, M.M.; Gericke, D.O.; Hallo, L.; Pépitone, K.; Kraus, D.; Schumacher, D.; Tauschwitz, An.; Vorberger, J.

2016-01-01

Simulations have been performed to study the energy loss of carbon ions in a hot, laser-generated plasma in the velocity region of the stopping-power maximum. In this parameter range, discrepancies of up to 30% exist between the various stopping theories and hardly any experimental data are available. The considered plasma, created by irradiating a thin carbon foil with two high-energy laser beams, is fully-ionized with a temperature of nearly 200 eV. To study the interaction at the maximum stopping power, Monte-Carlo calculations of the ion charge state in the plasma are carried out at a projectile energy of 0.5 MeV per nucleon. The predictions of various stopping-power theories are compared and experimental campaigns are planned for a first-time theory benchmarking in this low-velocity range. (paper)

A single European pharmaceutical market: Does maximum harmonization enhance medicinal product innovation?

DEFF Research Database (Denmark)

Faeh, Andrea Beata

2013-01-01

the orphan medicinal products scheme. The latter is subject to uniform Union rules specifically introduced to stimulate research and development and has led to the development of a number of new products. The article shows that the most radical positive integration depends to a large extent on the prospect...... – Innovation Union’ – market fragmentation to be one of the major causes of the lack of innovation. In order to establish if maximum harmonization benefits innovation, two distinct legal regimes in the pharmaceutical sector will be compared. The general rules for medicinal products are weighed against...... of it yielding revenue for the innovator. Hence, fuller harmonization can benefit innovation, but it is just as important, if not more important, to address other factors such as pricing, reimbursement and patent protection....

Energy balance of the lavender oil production

Directory of Open Access Journals (Sweden)

Osman GÖKDOĞAN

2016-06-01

Full Text Available This research was carried out to determine the energy input-output analysis of lavender oil production. Data from agricultural farms in Isparta province was used. Energy input was calculated as 1993.89 MJ and energy output was calculated as 2925.51 MJ. Wood energy, fresh stalked lavender flower energy, equipment energy, human labour energy, electricity energy, and water energy inputs were 54.22 %, 41.86 %, 3.40 %, 0.23 %, 0.18 %, and 0.10 % of energy inputs, respectively. In this production, it is noteworthy that wood was used as fuel in the lavender oil production distillation process as the highest input. In the energy outputs, an average of 3.10 kg lavender oil and 130 kg lavender water were extracted by processing 234 kg fresh stalked lavender flower. Energy use efficiency, specific energy, energy productivity, and net energy for lavender oil production were calculated as 1.47, 643.19 MJ kg-1, 0.002 kg MJ-1 and 931.62 MJ, respectively.

Energy production from biomass

International Nuclear Information System (INIS)

Bestebroer, S.I.

1995-01-01

The aim of the task group 'Energy Production from Biomass', initiated by the Dutch Ministry of Economic Affairs, was to identify bottlenecks in the development of biomass for energy production. The bottlenecks were identified by means of a process analysis of clean biomass fuels to the production of electricity and/or heat. The subjects in the process analysis are the potential availability of biomass, logistics, processing techniques, energy use, environmental effects, economic impact, and stimulation measures. Three categories of biomass are distinguished: organic residual matter, imported biomass, and energy crops, cultivated in the Netherlands. With regard to the processing techniques attention is paid to co-firing of clean biomass in existing electric power plants (co-firing in a coal-fired power plant or co-firing of fuel gas from biomass in a coal-fired or natural gas-fired power plant), and the combustion or gasification of clean biomass in special stand-alone installations. 5 figs., 13 tabs., 28 refs

Productivity response of calcareous nannoplankton to Eocene Thermal Maximum 2 (ETM2

Directory of Open Access Journals (Sweden)

M. Dedert

2012-05-01

Full Text Available The Early Eocene Thermal Maximum 2 (ETM2 at ~53.7 Ma is one of multiple hyperthermal events that followed the Paleocene-Eocene Thermal Maximum (PETM, ~56 Ma. The negative carbon excursion and deep ocean carbonate dissolution which occurred during the event imply that a substantial amount (10³ Gt of carbon (C was added to the ocean-atmosphere system, consequently increasing atmospheric CO₂(pCO₂. This makes the event relevant to the current scenario of anthropogenic CO₂ additions and global change. Resulting changes in ocean stratification and pH, as well as changes in exogenic cycles which supply nutrients to the ocean, may have affected the productivity of marine phytoplankton, especially calcifying phytoplankton. Changes in productivity, in turn, may affect the rate of sequestration of excess CO₂ in the deep ocean and sediments. In order to reconstruct the productivity response by calcareous nannoplankton to ETM2 in the South Atlantic (Site 1265 and North Pacific (Site 1209, we employ the coccolith Sr/Ca productivity proxy with analysis of well-preserved picked monogeneric populations by ion probe supplemented by analysis of various size fractions of nannofossil sediments by ICP-AES. The former technique of measuring Sr/Ca in selected nannofossil populations using the ion probe circumvents possible contamination with secondary calcite. Avoiding such contamination is important for an accurate interpretation of the nannoplankton productivity record, since diagenetic processes can bias the productivity signal, as we demonstrate for Sr/Ca measurements in the fine (<20 μm and other size fractions obtained from bulk sediments from Site 1265. At this site, the paleoproductivity signal as reconstructed from the Sr/Ca appears to be governed by cyclic changes, possibly orbital forcing, resulting in a 20–30% variability in Sr/Ca in dominant genera as obtained by ion probe. The ~13 to 21

Effect of temperature on energy potential of pyrolysis products from oil palm shells

Directory of Open Access Journals (Sweden)

Lina María Romero Millán

2016-06-01

Full Text Available Context: Taking into account that near 220 000 tons of oil palm shells are produced every year in Colombia, as a waste of the Elaeis Guineensis palm oil transformation process, the aim of this work is to determine the energy potential of oil palm shells, when transformed through slow pyrolysis process. Methods: Using a fixed bed lab scale reactor, different oil palm shells pyrolysis tests were performed between 300°C and 500°C. The effect of the temperature in the process product yield and in the energy content of produced solids and gases were analyzed. Results: With a maximum mass yield of 50%, the char is considered the main product of oil palm shells pyrolysis, containing up to 73% of the raw biomass energy. The heating value of char raised with the temperature, from 29,6 MJ/kg at 300°C to 31,34 MJ/kg at 500°C. Moreover, the gas produced in the established temperature range had up to 13% of the energy content of the raw biomass, with a heating value near 12,5 MJ/m3. Conclusions: According to the results, slow pyrolysis can be considered an interesting process for the valorization of residual biomass as oil palm shells, through the production of solids and gases that can be used as fuels, or as precursor of other value-added products.

Geothermal Energy as source or energy production

International Nuclear Information System (INIS)

Lozano, E.

1998-01-01

This article shows the use and utilization of geothermal energy. This calorific energy can be used, through the wells perforation, in generation of electricity and many other tasks. In Colombia is possible the utilization of this energy in the electrical production due to the volcanic presence in the Western and Central mountain chains

Power electronics and control techniques for maximum energy harvesting in photovoltaic systems

CERN Document Server

Femia, Nicola

2012-01-01

Incentives provided by European governments have resulted in the rapid growth of the photovoltaic (PV) market. Many PV modules are now commercially available, and there are a number of power electronic systems for processing the electrical power produced by PV systems, especially for grid-connected applications. Filling a gap in the literature, Power Electronics and Control Techniques for Maximum Energy Harvesting in Photovoltaic Systems brings together research on control circuits, systems, and techniques dedicated to the maximization of the electrical power produced by a photovoltaic (PV) so

Productivity feedback did not terminate the Paleocene-Eocene Thermal Maximum (PETM

Directory of Open Access Journals (Sweden)

A. Torfstein

2010-04-01

Full Text Available The Paleocene-Eocene Thermal Maximum (PETM occurred approximately 55 million years ago, and is one of the most dramatic abrupt global warming events in the geological record. This warming was triggered by the sudden release of thousands of gigatons of carbon into the atmosphere and is widely perceived to be the best analogue for current anthropogenic climate change. Yet, the mechanism of recovery from this event remains controversial. A massive increase in the intensity of the marine biological pump ("productivity feedback" has been suggested to cause a drawdown of atmospheric CO₂ and subsequent carbon sequestration in the ocean. A re-evaluation of the "productivity feedback hypothesis", based on biogenic barium mass accumulation rates (Ba-MARs for a site in the Southern Ocean, finds that any increase in export production lagged the initial carbon release by at least ~70 000 years. This implies that export production did not facilitate rapid removal of excess carbon from the atmosphere. Thus, the most likely mechanism for carbon removal appears to be silicate weathering, which occurred at much slower rates than previously assumed.

Multifield stochastic particle production: beyond a maximum entropy ansatz

Energy Technology Data Exchange (ETDEWEB)

Amin, Mustafa A.; Garcia, Marcos A.G.; Xie, Hong-Yi; Wen, Osmond, E-mail: mustafa.a.amin@gmail.com, E-mail: marcos.garcia@rice.edu, E-mail: hxie39@wisc.edu, E-mail: ow4@rice.edu [Physics and Astronomy Department, Rice University, 6100 Main Street, Houston, TX 77005 (United States)

2017-09-01

We explore non-adiabatic particle production for N {sub f} coupled scalar fields in a time-dependent background with stochastically varying effective masses, cross-couplings and intervals between interactions. Under the assumption of weak scattering per interaction, we provide a framework for calculating the typical particle production rates after a large number of interactions. After setting up the framework, for analytic tractability, we consider interactions (effective masses and cross couplings) characterized by series of Dirac-delta functions in time with amplitudes and locations drawn from different distributions. Without assuming that the fields are statistically equivalent, we present closed form results (up to quadratures) for the asymptotic particle production rates for the N {sub f}=1 and N {sub f}=2 cases. We also present results for the general N {sub f} >2 case, but with more restrictive assumptions. We find agreement between our analytic results and direct numerical calculations of the total occupation number of the produced particles, with departures that can be explained in terms of violation of our assumptions. We elucidate the precise connection between the maximum entropy ansatz (MEA) used in Amin and Baumann (2015) and the underlying statistical distribution of the self and cross couplings. We provide and justify a simple to use (MEA-inspired) expression for the particle production rate, which agrees with our more detailed treatment when the parameters characterizing the effective mass and cross-couplings between fields are all comparable to each other. However, deviations are seen when some parameters differ significantly from others. We show that such deviations become negligible for a broad range of parameters when N {sub f}>> 1.

Manufactering of par-fried french-fries. Part 3: a blueprint to predict the maximum production yield

NARCIS (Netherlands)

Somsen, D.J.; Capelle, A.; Tramper, J.

2004-01-01

Very little research on the production yield of par-fried French-fries has been reported in the literature. This paper bridges the knowledge gap and outlines the development of a model to predict the maximum production yield of par-fried French-fries. This yield model can be used to calculate the

Comments on a derivation and application of the 'maximum entropy production' principle

International Nuclear Information System (INIS)

Grinstein, G; Linsker, R

2007-01-01

We show that (1) an error invalidates the derivation (Dewar 2005 J. Phys. A: Math. Gen. 38 L371) of the maximum entropy production (MaxEP) principle for systems far from equilibrium, for which the constitutive relations are nonlinear; and (2) the claim (Dewar 2003 J. Phys. A: Math. Gen. 36 631) that the phenomenon of 'self-organized criticality' is a consequence of MaxEP for slowly driven systems is unjustified. (comment)

Energy budget and greenhouse gas balance evaluation of sustainable coppice systems for electricity production

International Nuclear Information System (INIS)

Lettens, Suzanna; Muys, Bart; Ceulemans, Reinhart; Moons, Ellen; Garcia, Juan; Coppin, Pol

2003-01-01

The use of bio-energy crops for electricity production is considered an effective means to mitigate the greenhouse effect, mainly due to its ability to substitute fossil fuels. A whole range of crops qualify for bio-energy production and a rational choice is not readily made. This paper evaluates the energy and greenhouse gas balance of a mixed indigenous hardwood coppice as an extensive, low-input bio-energy crop. The impact on fossil energy use and greenhouse gas emission is calculated and discussed by comparing its life cycle (cultivation, processing and conversion into energy) with two conventional bio-energy crops (short rotation systems of willow and Miscanthus). For each life cycle process, the flows of fossil energy and greenhouse gas that are created for the production of one functional unit are calculated. The results show that low-input bio-energy crops use comparatively less fossil fuel and avoid more greenhouse gas emission per unit of produced energy than conventional bio-energy crops during the first 100 yr. Where the mixed coppice system avoids up till 0.13 t CO 2 eq./GJ, Miscanthus does not exceed 0.07 t CO 2 eq./GJ. After 100 yr their performances become comparable, amounting to 0.05 t CO 2 eq./ha/GJ. However, if the land surface itself is chosen as a functional unit, conventional crops perform better with respect to mitigating the greenhouse effect. Miscanthus avoids a maximum of 12.9 t CO 2 eq./ha/yr, while mixed coppice attains 9.5 t CO 2 eq./ha/yr at the most

48 CFR 52.223-15 - Energy Efficiency in Energy-Consuming Products.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false Energy Efficiency in... Provisions and Clauses 52.223-15 Energy Efficiency in Energy-Consuming Products. As prescribed in 23.206, insert the following clause: Energy Efficiency in Energy-Consuming Products (DEC 2007) (a) Definition. As...

Energy production, nutrient recovery and greenhouse gas emission Potentials from Integrated Pig Manure Management Systems

DEFF Research Database (Denmark)

Prapaspongsa, Trakarn; Poulsen, Tjalfe; Hansen, Jens Aage

2010-01-01

of waste materials were considered. Data for the analyses were obtained from existing waste treatment facilities, experimental plants, laboratory measurements and literature. The assessment reveals that incineration combined with liquid/solid separation and drying of the solids is a promising management...... option yielding a high potential energy utilization rate and greenhouse gas savings. If maximum electricity production is desired, anaerobic digestion is advantageous as the biogas can be converted to electricity at high efficiency in a gas engine while allowing production of heat for operation...

Dissipated energy and entropy production for an unconventional heat engine: the stepwise `circular cycle'

Science.gov (United States)

di Liberto, Francesco; Pastore, Raffaele; Peruggi, Fulvio

2011-05-01

When some entropy is transferred, by means of a reversible engine, from a hot heat source to a colder one, the maximum efficiency occurs, i.e. the maximum available work is obtained. Similarly, a reversible heat pumps transfer entropy from a cold heat source to a hotter one with the minimum expense of energy. In contrast, if we are faced with non-reversible devices, there is some lost work for heat engines, and some extra work for heat pumps. These quantities are both related to entropy production. The lost work, i.e. ? , is also called 'degraded energy' or 'energy unavailable to do work'. The extra work, i.e. ? , is the excess of work performed on the system in the irreversible process with respect to the reversible one (or the excess of heat given to the hotter source in the irreversible process). Both quantities are analysed in detail and are evaluated for a complex process, i.e. the stepwise circular cycle, which is similar to the stepwise Carnot cycle. The stepwise circular cycle is a cycle performed by means of N small weights, dw, which are first added and then removed from the piston of the vessel containing the gas or vice versa. The work performed by the gas can be found as the increase of the potential energy of the dw's. Each single dw is identified and its increase, i.e. its increase in potential energy, evaluated. In such a way it is found how the energy output of the cycle is distributed among the dw's. The size of the dw's affects entropy production and therefore the lost and extra work. The distribution of increases depends on the chosen removal process.

Production of chemical energy carriers by non-expendable energy sources

Energy Technology Data Exchange (ETDEWEB)

Nitsch, J

1976-01-01

The different forms of energy (radiation, high-temperature heat and electricity) arising from non-expendable energy sources like solar energy can be used for the production of chemical energy-carriers. Possible methods are the splitting of water by means of photolysis, thermochemical cycles and electrolysis, as well as the storage of energy in closed loop chemical systems. These methods are described and efficiencies and costs of the production of these energy carriers are specified. Special problems of the long-distance transportation of hydrogen produced by solar energy are described and the resulting costs are estimated.

The maximum temperature of a thermodynamic cycle effect on weight-dimensional characteristics of the NPP energy blocks with air cooling

International Nuclear Information System (INIS)

Bezborodov, Yu.A.; Bubnov, V.P.; Nesterenko, V.B.

1982-01-01

The cycle maximum temperature effect on the properties of individual apparatuses and total NPP energy blocks characteristics has been investigated. Air, nitrogen, helium and chemically reacting system N 2 O 4 +2NO+O 2 have been considered as coolants. The conducted investigations have shown that maximum temperature of thermodynamical cycle affects considerably both the weight-dimensional characteristics of individual elements of NPP and total characteristics of NPP energy block. Energy blocks of NPP with air cooling wherein dissociating nitrogen tetroxide is used as working body, have better indexes on the majority of characteristics in comparison with blocks with air, nitrogen and helium cooling. If technical restrictions are to be taken into account (thermal resistance of metals, coolant decomposition under high temperatures, etc.) then dissociating nitrogen tetroxide should be recommended as working body and maximum cycle temperature in the range from 500 up to 600 deg C

Microbial surface displayed enzymes based biofuel cell utilizing degradation products of lignocellulosic biomass for direct electrical energy.

Science.gov (United States)

Fan, Shuqin; Hou, Chuantao; Liang, Bo; Feng, Ruirui; Liu, Aihua

2015-09-01

In this work, a bacterial surface displaying enzyme based two-compartment biofuel cell for the direct electrical energy conversion from degradation products of lignocellulosic biomass is reported. Considering that the main degradation products of the lignocellulose are glucose and xylose, xylose dehydrogenase (XDH) displayed bacteria (XDH-bacteria) and glucose dehydrogenase (GDH) displayed bacteria (GDH-bacteria) were used as anode catalysts in anode chamber with methylene blue as electron transfer mediator. While the cathode chamber was constructed with laccase/multi-walled-carbon nanotube/glassy-carbon-electrode. XDH-bacteria exhibited 1.75 times higher catalytic efficiency than GDH-bacteria. This assembled enzymatic fuel cell exhibited a high open-circuit potential of 0.80 V, acceptable stability and energy conversion efficiency. Moreover, the maximum power density of the cell could reach 53 μW cm(-2) when fueled with degradation products of corn stalk. Thus, this finding holds great potential to directly convert degradation products of biomass into electrical energy. Copyright © 2015 Elsevier Ltd. All rights reserved.

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.

Maruhn-Greiner Maximum for Confirmation of Low Energy Nuclear Reactions (LENR) via a Compound Nucleus with Double Magic Numbers

Science.gov (United States)

Hora, Heinrich; Miley, George

2007-03-01

One of the most convincing facts about LENR due to deuterons (ds) or protons of very high concentration in host metals of palladium is the measurement of the large scale minimum in the reaction probability with product elements centered around the nucleon number A = 153. The local maximum was measured in this region is similar to fission of uranium at A = 119 where the local maximum follows the Maruhn-Greiner mechanism^1. We suggest this phenomenon can be explained by the strong screening of the Maxwellian ds on the degenerate rigid electron background within the swimming electrons at the metal surface or thin filem interfaces. The deuterons behave like neutrals at distances of above 2 picometers (pm) and form clusters due to soft attraction in the range of thermal energy; 10 pm diameter clusters can react over long time scales (10^6 s) with Pd leading to double magic number compound nuclei 306x126 decaying via fission to an A=153 element distribution. J. Maruhn et al, Phys. Rev. Letters 32, 548 (1974) H. Hora, G.H. Miley, CzechJ. Phys. 48, 1111 (1998)

Investigation of Energy Indices and Energy Consumption Optimization for Peach Production- Case Study: Saman Region in Chaharmahal va Bakhtiari Province

Directory of Open Access Journals (Sweden)

M Ghasemi-Varnamkhasti

2015-03-01

Full Text Available As one of the most important conditions in sustainable agriculture, optimization of energy consumption in agriculture is necessary in order to reduce the production cost and saving non renewable resources as well as reduction of air pollutants. In this regard, this study was conducted in Saman region, Chaharmahal va Bakhtiari province. A linear programming based on Data Envelopment Analysis (DEA was used for optimization of energy consumption in peach production in order to increase the technical efficiency. By performing a linear regression analysis, some inputs including animal fertilizer, pesticide, human labor and machinery had no significant influence on product yield, while some other inputs including fuel, electricity, water and chemical fertilizer showed a significant effect on the product yield. Therefore, the latter inputs and the product yield were considered as the inputs and output, respectively. Selecting the BCC model (efficiency to variable scale model of input nature and using DEA Solver software, efficient and inefficient farmers were determined. The efficient farmers had the technical efficiency of unit (one and the inefficient farmers had this value within 0.47-0.94. Also, the technical efficiency of inefficient farmers was computed as 0.74. This means that using 74% of the inputs and keeping the current yield, the inefficient farmers can approach to the efficiency limit. Total technical efficiency of all farmers was found to be 0.82. Based on the results, the maximum value of inefficiency belonged to electricity energy with 65.32%.

Determining Mean Annual Energy Production

DEFF Research Database (Denmark)

Kofoed, Jens Peter; Folley, Matt

2016-01-01

This robust book presents all the information required for numerical modelling of a wave energy converter, together with a comparative review of the different available techniques. The calculation of the mean annual energy production (MAEP) is critical to the assessment of the levelized cost...... of energy for a wave energy converter or wave farm. Fundamentally, the MAEP is equal to the sum of the product of the power capture of a set of sea-states and their average annual occurrence. In general, it is necessary in the calculation of the MAEP to achieve a balance between computational demand...

Petroleum production at Maximum Efficient Rate Naval Petroleum Reserve No. 1 (Elk Hills), Kern County, California

International Nuclear Information System (INIS)

1993-07-01

This document provides an analysis of the potential impacts associated with the proposed action, which is continued operation of Naval Petroleum Reserve No. I (NPR-1) at the Maximum Efficient Rate (MER) as authorized by Public law 94-258, the Naval Petroleum Reserves Production Act of 1976 (Act). The document also provides a similar analysis of alternatives to the proposed action, which also involve continued operations, but under lower development scenarios and lower rates of production. NPR-1 is a large oil and gas field jointly owned and operated by the federal government and Chevron U.SA Inc. (CUSA) pursuant to a Unit Plan Contract that became effective in 1944; the government's interest is approximately 78% and CUSA's interest is approximately 22%. The government's interest is under the jurisdiction of the United States Department of Energy (DOE). The facility is approximately 17,409 acres (74 square miles), and it is located in Kern County, California, about 25 miles southwest of Bakersfield and 100 miles north of Los Angeles in the south central portion of the state. The environmental analysis presented herein is a supplement to the NPR-1 Final Environmental Impact Statement of that was issued by DOE in 1979 (1979 EIS). As such, this document is a Supplemental Environmental Impact Statement (SEIS)

Barriers to retail marketing of renewable energy products in an energy-rich province

International Nuclear Information System (INIS)

Haner, S.A.

1999-01-01

Personal experiences in attempting to market photovoltaics and other renewable energy products in Alberta, a province rich in energy sources, are recounted as part of an exploration of ways to help industry to develop strategies that will advance the acceptance of renewable energy products, particularly in areas of the world that are not concerned about energy supply. Social acceptability, emphasis on a healthy and convenient lifestyle associated with renewable energy products, practical, user-friendly products, and competitive prices, are some of the key elements in successfully marketing renewable energy products

L1 Adaptive Speed Control of a Small Wind Energy Conversion System for Maximum Power Point Tracking

DEFF Research Database (Denmark)

Zhao, Haoran; Wu, Qiuwei; Rasmussen, Claus Nygaard

2014-01-01

This paper presents the design of an L1 adaptive controller for maximum power point tracking (MPPT) of a small variable speed Wind Energy Conversion System (WECS). The proposed controller generates the optimal torque command for the vector controlled generator side converter (GSC) based on the wi......) is used to carry out case studies using Matlab/Simulink. The case study results show that the designed L1 adaptive controller has good tracking performance even with unmodeled dynamics and in the presence of parameter uncertainties and unknown disturbances.......This paper presents the design of an L1 adaptive controller for maximum power point tracking (MPPT) of a small variable speed Wind Energy Conversion System (WECS). The proposed controller generates the optimal torque command for the vector controlled generator side converter (GSC) based on the wind...

France's energy balance for 2014: production peak and a consumption low

International Nuclear Information System (INIS)

Rouquette, Celine

2015-07-01

2014 was the warmest year since 1900 in France and in the rest of the world. In particular, the mild winter led to heating needs 7 million tonnes of oil equivalent (Mtoe) lower than the needs in an average year. Real primary energy consumption fell below the symbolic 250 Mtoe level, a low it had not reached since 1995. Although energy demand decreased, national primary energy production increased for the second year running, reaching 139 Mtoe, a little over 1 Mtoe higher than in 2013. This rise in production is explained by nuclear generated electricity. The 2014 physical trade deficit for energy therefore decreased significantly, by 10 Mtoe, to below 114 Mtoe. Such a low level had not been observed since 1988. The level of energy self-sufficiency rose sharply in 2014, to 55.8%, a level not hitherto reached. The decrease in net energy imports was accompanied by a drop in quoted prices for energy products on the European and international markets. As a result, France's energy bill was 17% lower than in 2013. At around euro 55 billion, it fell to a level close to that of the early 1980's. Even excluding the effects of the higher temperatures in 2014, thereby adjusting for climate variations, primary energy went from 275 Mtoe - its maximum, reached in 2005 - to 257 Mtoe, with an average annual decrease of -2 Mtoe, confirming the downward trend initiated in the mid-2000's. Final energy consumption was 150 Mtoe in 2014, the lowest level since 1996. It decreased by a little more than 1% in relation to 2013, with reductions in all sectors except for transport, where consumption remained stable. (author)

The impact of predicted demand on energy production

Science.gov (United States)

El kafazi, I.; Bannari, R.; Aboutafail, My. O.

2018-05-01

Energy is crucial for human life, a secure and accessible supply of power is essential for the sustainability of societies. Economic development and demographic progression increase energy demand, prompting countries to conduct research and studies on energy demand and production. Although, increasing in energy demand in the future requires a correct determination of the amount of energy supplied. Our article studies the impact of demand on energy production to find the relationship between the two latter and managing properly the production between the different energy sources. Historical data of demand and energy production since 2000 are used. The data are processed by the regression model to study the impact of demand on production. The obtained results indicate that demand has a positive and significant impact on production (high impact). Production is also increasing but at a slower pace. In this work, Morocco is considered as a case study.

Impact of Climate Change on Energy Production, Distribution, and Consumption in Russia

Science.gov (United States)

Klimenko, V. V.; Klimenko, A. V.; Tereshin, A. G.; Fedotova, E. V.

2018-05-01

An assessment of the overall impact of the observed and expected climatic changes on energy production, distribution, and consumption in Russia is presented. Climate model results of various complexity and evaluation data on the vulnerability of various energy production sectors to climate change are presented. It is shown that, due to the increase of air temperature, the efficiency of electricity production at thermal and nuclear power plants declines. According to the climate model results, the production of electricity at TPPs and NPPs by 2050 could be reduced by 6 billion kW h due to the temperature increase. At the same time, as a result of simulation, the expected increase in the rainfall amount and river runoff in Russia by 2050 could lead to an increase in the output of HPP by 4-6% as compared with the current level, i.e., by 8 billion kW h. For energy transmission and distribution, the climate warming will mean an increase in transmission losses, which, according to estimates, may amount to approximately 1 billion kW h by 2050. The increase of air temperature in summer will require higher energy consumption for air conditioning, which will increase by approximately 6 billion kW h by 2050. However, in total, the optimal energy consumption in Russia, corresponding to the postindustrial level, will decrease by 2050 by approximately 150 billion kW h as a result of climate- induced changes. The maximum global warming impact is focused on the heat demand sector. As a result of a decrease in the heating degree-days by 2050, the need for space heating is expected to fall by 10-15%, which will cause a fuel conservation sufficient for generating approximately 140 billion kW h of electricity. Hence, a conclusion about the positive direct impact of climate change on the Russia's energy sector follows, which is constituted in the additional available energy resource of approximately 300 billion kW h per year.

Energy aspects of microalgal biodiesel production

Directory of Open Access Journals (Sweden)

Edith Martinez-Guerra

2016-03-01

Full Text Available Algal biodiesel production will play a significant role in sustaining future transportation fuel supplies. A large number of researchers around the world are investigating into making this process sustainable by increasing the energy gains and by optimizing resource-utilization efficiencies. Although, research is being pursued aggressively in all aspects of algal biodiesel production from microalgal cell cultivation, cell harvesting, and extraction and transesterification steps to the final product separation and purification, there is a large disparity in the data presented in recent reports making it difficult to assess the real potential of microalgae as a future energy source. This article discusses some of the key issues in energy consumption in the process of algal biodiesel production and identifies the areas for improvement to make this process energy-positive and sustainable.

Potential benefits from improved energy efficiency of key electrical products: The case of India

International Nuclear Information System (INIS)

McNeil, Michael A.; Iyer, Maithili; Meyers, Stephen; Letschert, Virginie E.; McMahon, James E.

2008-01-01

The economy of the world's second most populous country continues to grow rapidly, bringing prosperity to a growing middle class while further straining an energy infrastructure already stretched beyond capacity. At the same time, efficiency policy initiatives have gained a foothold in India, and promise to grow in number over the coming years. This paper considers the maximum cost-effective potential of efficiency improvement for key energy-consuming products in the Indian context. The products considered are: household refrigerators, window air conditioners, motors and distribution transformers. Together, these products account for about 27% of delivered electricity consumption in India. The analysis estimates the minimum Life-Cycle Cost option for each product class, according to use patterns and prevailing customer marginal rates in each sector. This option represents an efficiency improvement ranging between 12% and 60%, depending on product class. If this level of efficiency was achieved starting in 2010, we estimate that total electricity consumption in India could be reduced by 4.7% by 2020, saving over 74 million tons of oil equivalent and over 246 million tons of carbon dioxide emissions. Net present financial savings of this efficiency improvement totals 8.1 billion dollars

Energy, carbon dioxide and water use implications of hydrous ethanol production

International Nuclear Information System (INIS)

Saffy, Howard A.; Northrop, William F.; Kittelson, David B.; Boies, Adam M.

2015-01-01

Highlights: • We use a chemical refinery model and exergy analysis to determine the impact of hydrous ethanol. • The process is 70% efficient with 86% of the losses from fermentation, steam generation and drying. • We found that producing 86 wt% ethanol is optimal for thermal energy consumption. • Hydrous ethanol production can reduce energy costs and emissions by ∼8%. • Hydrous ethanol reduces water use by decreasing evaporation in cooling towers. - Abstract: Sub-azeotropic hydrous ethanol has been demonstrated as an effective diesel fuel replacement when used in dual-fuel compression ignition engines. Previous studies have also suggested that hydrous ethanol may be more efficient to produce from corn than anhydrous ethanol. In this study, we investigate corn ethanol production from a dry-mill, natural gas-fired corn ethanol refinery, producing ethanol with a range of ethanol concentrations from 58 wt% to 100 wt% to determine the effect on energy use, water consumption and greenhouse gas (GHG) emissions in the refining stage of the corn ethanol lifecycle. A second law (exergy) analysis of anhydrous ethanol refining revealed the overall process to be 70% efficient, whereby 86% of the exergy losses could be accounted for by three processes: fermentation (34%), steam generation (29%) and distiller’s grains and solubles drying (23%). We found that producing 86 wt% ethanol is optimal as thermal energy consumption decreases by a maximum of 10% (from 7.7 MJ/L to 6.9 MJ/L). These savings have the potential to reduce energy costs by approximately 8% ($0.34/L) and reduce refinery emissions by 8% (2 g CO 2 e/MJ). Production of hydrous ethanol reduced refinery water use due to decreased evaporative losses in the cooling towers, leading to water savings of between 3% and 6% at 86 wt% ethanol.

Determination of Energy Use Efficiency of Sesame Production

OpenAIRE

BARAN, Mehmet Firat

2018-01-01

In this research it was aimed to determine an energy use efficiency of sesame production in Şanlıurfa province, during the production season of 2015. In order to determine the energy use efficiency of sesame production, trials and measurement were performed in sesame farm in the Bozova district of Şanlıurfa province. As energy inputs, human labour energy, machinery energy, chemical fertilizers energy, irrigation water energy, chemicals energy, diesel fuel energy and seed energy as were calcul...

Long-term affected energy production of waste to energy technologies identified by use of energy system analysis

DEFF Research Database (Denmark)

Münster, Marie; Meibom, Peter

2010-01-01

Affected energy production is often decisive for the outcome of consequential life-cycle assessments when comparing the potential environmental impact of products or services. Affected energy production is however difficult to determine. In this article the future long-term affected energy...... production is identified by use of energy system analysis. The focus is on different uses of waste for energy production. The Waste-to-Energy technologies analysed include co-combustion of coal and waste, anaerobic digestion and thermal gasification. The analysis is based on optimization of both investments...... and production of electricity, district heating and bio-fuel in a future possible energy system in 2025 in the countries of the Northern European electricity market (Denmark, Norway, Sweden, Finland and Germany). Scenarios with different CO2 quota costs are analysed. It is demonstrated that the waste...

Maximizing the transferred power to electric arc furnace for having maximum production

International Nuclear Information System (INIS)

Samet, Haidar; Ghanbari, Teymoor; Ghaisari, Jafar

2014-01-01

In order to increase production of an EAF (electric arc furnace) by reduction of melting time, one can increase transferred power to the EAF. In other words a certain value of energy can be transferred to the EAF in less time. The transferred power to the EAF reduces when series reactors are utilized in order to have stable arc with desired characteristics. To compensate the reduced transferred power, the secondary voltage of the EAF transformer should be increased by tap changing of the transformer. On the other hand, after any tap changing of the EAF transformer, improved arc stability is degraded. Therefore, the series reactor and EAF transformer tap changing should be simultaneously determined to achieve arc with desired characteristics. In this research, three approaches are proposed to calculate the EAF system parameters, by which the optimal set-points of the different series reactor and EAF transformer taps are determined. The electric characteristics relevant to the EAF for the all transformer and series reactor taps with and without SVC (static VAr compensator) are plotted and based on these graphs the optimal set-points are tabulated. Finally, an economic evaluation is also presented for the methods. - Highlights: • The main goal is to transfer the maximum power to electric arc furnace. • Optimal transformer and series reactor taps are determined. • Arc stability and transferred power to EAF determine the optimal performance. • An economic assessment is done and the number of increased meltings is calculated

The role of energy policy in agricultural biogas energy production in Visegrad countries

Directory of Open Access Journals (Sweden)

Chodkowska-Miszczuk Justyna

2017-03-01

Full Text Available Energy production by agricultural biogas plants has recently recorded considerable growth in Visegrad countries. The development was enhanced by European Union’s efforts to increase the proportion of energy produced from renewable sources. The paper aims to assess the role of energy policy in the development of agricultural biogas energy production in Visegrad region. Conducted studies have shown that among various forms of support for energy production from renewable energy sources, the price system prevails, including the support by feed in tariffs and bonuses. Feed in tariffs were adopted in Czech Republic, Hungary and Slovakia. Another kind of support system – a quota system – was adopted in Poland, what includes tendering and certificate systems. The results confirm the adoption of legal framework was necessary step to enable agricultural biogas energy production in Visegrad countries, but itself it was not enough to stimulate development of agricultural biogas energy production significantly. Rapid development in each country was recorded only after the certain financial support systems took effect, what made production of agricultural biogas energy economically efficient for investors. The production of energy from agricultural biogas grew the most in the Czech Republic and Slovakia, where the financial support was the highest. Nevertheless, the protracted process of changes in legal framework and transformation of energy policy, certain measures including state-controlled price-making systems, risk regarding with auction system might hamper agricultural biogas energy production further development.

Erich Regener and the ionisation maximum of the atmosphere

Science.gov (United States)

Carlson, P.; Watson, A. A.

2014-12-01

In the 1930s the German physicist Erich Regener (1881-1955) did important work on the measurement of the rate of production of ionisation deep under water and in the atmosphere. Along with one of his students, Georg Pfotzer, he discovered the altitude at which the production of ionisation in the atmosphere reaches a maximum, often, but misleadingly, called the Pfotzer maximum. Regener was one of the first to estimate the energy density of cosmic rays, an estimate that was used by Baade and Zwicky to bolster their postulate that supernovae might be their source. Yet Regener's name is less recognised by present-day cosmic ray physicists than it should be, largely because in 1937 he was forced to take early retirement by the National Socialists as his wife had Jewish ancestors. In this paper we briefly review his work on cosmic rays and recommend an alternative naming of the ionisation maximum. The influence that Regener had on the field through his son, his son-in-law, his grandsons and his students, and through his links with Rutherford's group in Cambridge, is discussed in an appendix. Regener was nominated for the Nobel Prize in Physics by Schrödinger in 1938. He died in 1955 at the age of 73.

Origin of a maximum of the astrophysical S factor in heavy-ion fusion reactions at deep subbarrier energies

Science.gov (United States)

Hagino, K.; Balantekin, A. B.; Lwin, N. W.; Thein, Ei Shwe Zin

2018-03-01

The hindrance phenomenon of heavy-ion fusion cross sections at deep subbarrier energies often accompanies a maximum of an astrophysical S factor at a threshold energy for fusion hindrance. We argue that this phenomenon can naturally be explained when the fusion excitation function is fitted with two potentials, with a larger (smaller) logarithmic slope at energies lower (higher) than the threshold energy. This analysis clearly suggests that the astrophysical S factor provides a convenient tool to analyze the deep subbarrier hindrance phenomenon, even though the S factor may have a strong energy dependence for heavy-ion systems unlike that for astrophysical reactions.

The maximum economic depth of groundwater abstraction for irrigation

Science.gov (United States)

Bierkens, M. F.; Van Beek, L. P.; de Graaf, I. E. M.; Gleeson, T. P.

2017-12-01

Over recent decades, groundwater has become increasingly important for agriculture. Irrigation accounts for 40% of the global food production and its importance is expected to grow further in the near future. Already, about 70% of the globally abstracted water is used for irrigation, and nearly half of that is pumped groundwater. In many irrigated areas where groundwater is the primary source of irrigation water, groundwater abstraction is larger than recharge and we see massive groundwater head decline in these areas. An important question then is: to what maximum depth can groundwater be pumped for it to be still economically recoverable? The objective of this study is therefore to create a global map of the maximum depth of economically recoverable groundwater when used for irrigation. The maximum economic depth is the maximum depth at which revenues are still larger than pumping costs or the maximum depth at which initial investments become too large compared to yearly revenues. To this end we set up a simple economic model where costs of well drilling and the energy costs of pumping, which are a function of well depth and static head depth respectively, are compared with the revenues obtained for the irrigated crops. Parameters for the cost sub-model are obtained from several US-based studies and applied to other countries based on GDP/capita as an index of labour costs. The revenue sub-model is based on gross irrigation water demand calculated with a global hydrological and water resources model, areal coverage of crop types from MIRCA2000 and FAO-based statistics on crop yield and market price. We applied our method to irrigated areas in the world overlying productive aquifers. Estimated maximum economic depths range between 50 and 500 m. Most important factors explaining the maximum economic depth are the dominant crop type in the area and whether or not initial investments in well infrastructure are limiting. In subsequent research, our estimates of

Energy production and financial analysis of photovoltaic energy plants in Ivory Coast

OpenAIRE

Guaita Pradas, Inmaculada; Marí Soucase, Bernabé; BOKO, AKA

2015-01-01

One key factor for boosting economic growth in developing countries is the energetic independence of the countries. Renewable energies are well suited for such purpose even if effective dissemination of renewable energies is their production price. The energy production of solar plants is highly dependent of both sun radiation and climate data and therefore dependent of their location. This paper reports on the economic and financial calculations related to the energy production of a standard...

IT support of energy-sensitive product development. Energy-efficient product and process innovations in production engineering. Virtual product development for energy-efficient products and processes; IT-Unterstuetzung zur energiesensitiven Produktentwicklung. Energieeffiziente Produkt- und Prozessinnovationen in der Produktionstechnik. Handlungsfeld virtuelle Produktentwicklung fuer energieeffiziente Produkte und Prozesse (PE)

Energy Technology Data Exchange (ETDEWEB)

Reichel, Thomas; Ruenger, Gudula; Steger, Daniel; Xu, Haibin

2010-07-07

The development of low-cost, energy-saving and resources-saving products is increasingly important. Thecalculation of the life cycle cost is an important basis for this. For this, it is necessary to extract empirical, decision-relevant data from IT systems of product development (e.g. product data management systems) and operation (e.g. enterprise resource planning systems), and to give the planner appropriate methods for data aggregation. Life cycle data are particularly important for optimising energy efficiency, which may be achieved either by enhanced productivity at constant energy consumption or by reduced energy consumption at constant productivity. The report presents an IT view of the product development process. First, modern methods of product development are analysed including IT support and IT systems. Requirements on IT systems are formulated which enable energy efficiency assessment and optimisation in all phases of product development on the basis of the IT systems used. IT systems for energy-sensitive product development will support the construction engineer in the development of energy-efficient products. For this, the functionalities of existing PDM systems must be enhanced by methods of analysis, synthesis and energy efficiency assessment. Finally, it is shown how the methods for analyzing energy-relevant data can be integrated in the work flow.

User's guide: Nimbus-7 Earth radiation budget narrow-field-of-view products. Scene radiance tape products, sorting into angular bins products, and maximum likelihood cloud estimation products

Science.gov (United States)

Kyle, H. Lee; Hucek, Richard R.; Groveman, Brian; Frey, Richard

1990-01-01

The archived Earth radiation budget (ERB) products produced from the Nimbus-7 ERB narrow field-of-view scanner are described. The principal products are broadband outgoing longwave radiation (4.5 to 50 microns), reflected solar radiation (0.2 to 4.8 microns), and the net radiation. Daily and monthly averages are presented on a fixed global equal area (500 sq km), grid for the period May 1979 to May 1980. Two independent algorithms are used to estimate the outgoing fluxes from the observed radiances. The algorithms are described and the results compared. The products are divided into three subsets: the Scene Radiance Tapes (SRT) contain the calibrated radiances; the Sorting into Angular Bins (SAB) tape contains the SAB produced shortwave, longwave, and net radiation products; and the Maximum Likelihood Cloud Estimation (MLCE) tapes contain the MLCE products. The tape formats are described in detail.

The limits of the integration of intermittent electricity productions

International Nuclear Information System (INIS)

Nifenecker, Herve

2013-01-01

Addressing the issue of intermittency of renewable energies and the associated need of an available spare energy, the author states that the installed nuclear power cannot be significantly decreased by a development of photovoltaic and wind energy productions. He shows that the maximum share of renewable energy which can be used in the energy mix is its load factor. In the case of wind energy, he formulates a set of theorems which notably address the possibilities to avoid an overproduction of wind energy, the assessment of the controllable production, the maximum share of wind energy. Based on these theorems, he computes the purchase cost of wind energy and the avoided cost of nuclear production. He addresses the case of photovoltaic energy for which he outlines the perspectives and obstacles related to energy storage

Net energy yield from production of conventional oil

International Nuclear Information System (INIS)

Dale, Michael; Krumdieck, Susan; Bodger, Pat

2011-01-01

Historic profitability of bringing oil to market was profound, but most easy oil has been developed. Higher cost resources, such as tar sands and deep off-shore, are considered the best prospects for the future. Economic modelling is currently used to explore future price scenarios commensurate with delivering fuel to market. Energy policy requires modelling scenarios capturing the complexity of resource and extraction aspects as well as the economic profitability of different resources. Energy-return-on-investment (EROI) expresses the profitability of bringing energy products to the market. Net energy yield (NEY) is related to the EROI. NEY is the amount of energy less expenditures necessary to deliver a fuel to the market. This paper proposes a pattern for EROI of oil production, based on historic oil development trends. Methodology and data for EROI is not agreed upon. The proposed EROI function is explored in relation to the available data and used to attenuate the International Energy Agency (IEA) world oil production scenarios to understand the implications of future declining EROI on net energy yield. The results suggest that strategies for management and mitigation of deleterious effects of a peak in oil production are more urgent than might be suggested by analyses focussing only on gross production. - Highlights: → Brief introduction to methodological issues concerning net energy analysis. → Description of EROI function over the whole production cycle of an energy resource. → Calibration of this function to EROI data from historic oil production. → Application to determine the net energy yield from current global oil production. → Calculation of net energy yield from IEA projections of future oil production.

Nuclear energy for sustainable Hydrogen production

International Nuclear Information System (INIS)

Gyoshev, G.

2004-01-01

There is general agreement that hydrogen as an universal energy carrier could play increasingly important role in energy future as part of a set of solutions to a variety of energy and environmental problems. Given its abundant nature, hydrogen has been an important raw material in the organic chemical industry. At recent years strong competition has emerged between nations as diverse as the U.S., Japan, Germany, China and Iceland in the race to commercialize hydrogen energy vehicles in the beginning of 21st Century. Any form of energy - fossil, renewable or nuclear - can be used to generate hydrogen. The hydrogen production by nuclear electricity is considered as a sustainable method. By our presentation we are trying to evaluate possibilities for sustainable hydrogen production by nuclear energy at near, medium and long term on EC strategic documents basis. The main EC documents enter water electrolysis by nuclear electricity as only sustainable technology for hydrogen production in early stage of hydrogen economy. In long term as sustainable method is considered the splitting of water by thermochemical technology using heat from high temperature reactors too. We consider that at medium stage of hydrogen economy it is possible to optimize the sustainable hydrogen production by high temperature and high pressure water electrolysis by using a nuclear-solar energy system. (author)

Mobile energy recording unit - the basis to improve energy productivity with principles of lean production; Mobile Energie-Erfassungseinheit (MobEE). Eine Grundlage zur Steigerung der Energieproduktivitaet auf Basis von Lean Production Prinzipien

Energy Technology Data Exchange (ETDEWEB)

Schnellbach, Peter [Fraunhofer IWU, Augsburg (Germany). Projektgruppe fuer Ressourceneffiziente mechatronische Verarbeitungsmaschinen; Beisbart, Ulrich [BMW Group, Muenchen (Germany). Abt. Steuerung Facility Management, Energie, Mobilitaet, Dienstleistungsmanagement; Reinhardt, Gunther [Technische Univ. Muenchen (Germany). Inst. fuer Werkzeugmaschinen und Betriebswissenschaften; RMV Augsburg (Germany). IWU Projektguppe; Schneider, Oliver

2012-10-15

Improvement of energy productivity in production processes will become more important in future. As one large customer, manufacturing industry has to take responsibility to make its contribution in this field. The mobile energy recording unit helps to create the necessary transparency to identify possible energy savings on the basis of lean production principles.

Space-time dependence between energy sources and climate related energy production

Science.gov (United States)

Engeland, Kolbjorn; Borga, Marco; Creutin, Jean-Dominique; Ramos, Maria-Helena; Tøfte, Lena; Warland, Geir

2014-05-01

The European Renewable Energy Directive adopted in 2009 focuses on achieving a 20% share of renewable energy in the EU overall energy mix by 2020. A major part of renewable energy production is related to climate, called "climate related energy" (CRE) production. CRE production systems (wind, solar, and hydropower) are characterized by a large degree of intermittency and variability on both short and long time scales due to the natural variability of climate variables. The main strategies to handle the variability of CRE production include energy-storage, -transport, -diversity and -information (smart grids). The three first strategies aim to smooth out the intermittency and variability of CRE production in time and space whereas the last strategy aims to provide a more optimal interaction between energy production and demand, i.e. to smooth out the residual load (the difference between demand and production). In order to increase the CRE share in the electricity system, it is essential to understand the space-time co-variability between the weather variables and CRE production under both current and future climates. This study presents a review of the literature that searches to tackle these problems. It reveals that the majority of studies deals with either a single CRE source or with the combination of two CREs, mostly wind and solar. This may be due to the fact that the most advanced countries in terms of wind equipment have also very little hydropower potential (Denmark, Ireland or UK, for instance). Hydropower is characterized by both a large storage capacity and flexibility in electricity production, and has therefore a large potential for both balancing and storing energy from wind- and solar-power. Several studies look at how to better connect regions with large share of hydropower (e.g., Scandinavia and the Alps) to regions with high shares of wind- and solar-power (e.g., green battery North-Sea net). Considering time scales, various studies consider wind

Minimal length, Friedmann equations and maximum density

Energy Technology Data Exchange (ETDEWEB)

Awad, Adel [Center for Theoretical Physics, British University of Egypt,Sherouk City 11837, P.O. Box 43 (Egypt); Department of Physics, Faculty of Science, Ain Shams University,Cairo, 11566 (Egypt); Ali, Ahmed Farag [Centre for Fundamental Physics, Zewail City of Science and Technology,Sheikh Zayed, 12588, Giza (Egypt); Department of Physics, Faculty of Science, Benha University,Benha, 13518 (Egypt)

2014-06-16

Inspired by Jacobson’s thermodynamic approach, Cai et al. have shown the emergence of Friedmann equations from the first law of thermodynamics. We extend Akbar-Cai derivation http://dx.doi.org/10.1103/PhysRevD.75.084003 of Friedmann equations to accommodate a general entropy-area law. Studying the resulted Friedmann equations using a specific entropy-area law, which is motivated by the generalized uncertainty principle (GUP), reveals the existence of a maximum energy density closed to Planck density. Allowing for a general continuous pressure p(ρ,a) leads to bounded curvature invariants and a general nonsingular evolution. In this case, the maximum energy density is reached in a finite time and there is no cosmological evolution beyond this point which leaves the big bang singularity inaccessible from a spacetime prospective. The existence of maximum energy density and a general nonsingular evolution is independent of the equation of state and the spacial curvature k. As an example we study the evolution of the equation of state p=ωρ through its phase-space diagram to show the existence of a maximum energy which is reachable in a finite time.

Scenarios for power production with biomass in the Finnish forest industry

International Nuclear Information System (INIS)

Nousiainen, I.K.; Malinen, H.O.; Villa, A.O.

1997-01-01

This study presents three scenarios for power production with biomass in Finnish pulp and paper mills. The basic scenario assumes that the production capacity in the forest industry increases as in the past. The green energy scenario assumes that there is a strong demand from the market for sustainable green energy production. The maximum scenario assumes that the production capacity of chemical pulp increases significantly and the use of wood raw material extends to the maximum level. According to the basic scenario the use of biofuels in the pulp and paper mills will increase from starting level, 3.24 Mtoe in 1992, to 5.07 Mtoe by the year 2010. The utilization potential of biofuels will increase to 5.45 Mtoe in green energy and to 6.43 Mtoe in the maximum biofuels scenario. The power production with biomass will increase from the starting level, 572 MW in 1992, to 930 MW in the basic, to 1 100 MW in the green energy and to 1 670 MW in the maximum biofuels scenario by the year 2010. (author)

Microwatt power consumption maximum power point tracking circuit using an analogue differentiator for piezoelectric energy harvesting

Science.gov (United States)

Chew, Z. J.; Zhu, M.

2015-12-01

A maximum power point tracking (MPPT) scheme by tracking the open-circuit voltage from a piezoelectric energy harvester using a differentiator is presented in this paper. The MPPT controller is implemented by using a low-power analogue differentiator and comparators without the need of a sensing circuitry and a power hungry controller. This proposed MPPT circuit is used to control a buck converter which serves as a power management module in conjunction with a full-wave bridge diode rectifier. Performance of this MPPT control scheme is verified by using the prototyped circuit to track the maximum power point of a macro-fiber composite (MFC) as the piezoelectric energy harvester. The MFC was bonded on a composite material and the whole specimen was subjected to various strain levels at frequency from 10 to 100 Hz. Experimental results showed that the implemented full analogue MPPT controller has a tracking efficiency between 81% and 98.66% independent of the load, and consumes an average power of 3.187 μW at 3 V during operation.

ENERGY STAR Certified Roof Products

Data.gov (United States)

U.S. Environmental Protection Agency — Certified models meet all ENERGY STAR requirements as listed in the Version 3.0 ENERGY STAR Program Requirements for Roof Products that are effective as of July 1,...

Effects of steam pretreatment and co-production with ethanol on the energy efficiency and process economics of combined biogas, heat and electricity production from industrial hemp

Science.gov (United States)

2013-01-01

Background The study presented here has used the commercial flow sheeting program Aspen Plus™ to evaluate techno-economic aspects of large-scale hemp-based processes for producing transportation fuels. The co-production of biogas, district heat and power from chopped and steam-pretreated hemp, and the co-production of ethanol, biogas, heat and power from steam-pretreated hemp were analysed. The analyses include assessments of heat demand, energy efficiency and process economics in terms of annual cash flows and minimum biogas and ethanol selling prices (MBSP and MESP). Results Producing biogas, heat and power from chopped hemp has the highest overall energy efficiency, 84% of the theoretical maximum (based on lower heating values), providing that the maximum capacity of district heat is delivered. The combined production of ethanol, biogas, heat and power has the highest energy efficiency (49%) if district heat is not produced. Neither the inclusion of steam pretreatment nor co-production with ethanol has a large impact on the MBSP. Ethanol is more expensive to produce than biogas is, but this is compensated for by its higher market price. None of the scenarios examined are economically viable, since the MBSP (EUR 103–128 per MWh) is higher than the market price of biogas (EUR 67 per MWh). The largest contribution to the cost is the cost of feedstock. Decreasing the retention time in the biogas process for low solids streams by partly replacing continuous stirred tank reactors by high-rate bioreactors decreases the MBSP. Also, recycling part of the liquid from the effluent from anaerobic digestion decreases the MBSP. The production and prices of methane and ethanol influence the process economics more than the production and prices of electricity and district heat. Conclusions To reduce the production cost of ethanol and biogas from biomass, the use of feedstocks that are cheaper than hemp, give higher output of ethanol and biogas, or combined production with

Energy security for India: Biofuels, energy efficiency and food productivity

International Nuclear Information System (INIS)

Gunatilake, Herath; Roland-Holst, David; Sugiyarto, Guntur

2014-01-01

The emergence of biofuel as a renewable energy source offers opportunities for significant climate change mitigation and greater energy independence to many countries. At the same time, biofuel represents the possibility of substitution between energy and food. For developing countries like India, which imports over 75% of its crude oil, fossil fuels pose two risks—global warming pollution and long-term risk that oil prices will undermine real living standards. This paper examines India's options for managing energy price risk in three ways: biofuel development, energy efficiency promotion, and food productivity improvements. Our salient results suggest that biodiesel shows promise as a transport fuel substitute that can be produced in ways that fully utilize marginal agricultural resources and hence promote rural livelihoods. First-generation bioethanol, by contrast, appears to have a limited ability to offset the impacts of oil price hikes. Combining the biodiesel expansion policy with energy efficiency improvements and food productivity increases proved to be a more effective strategy to enhance both energy and food security, help mitigate climate change, and cushion the economy against oil price shocks. - Highlights: • We investigate the role of biofuels in India applying a CGE model. • Biodiesel enhances energy security and improve rural livelihoods. • Sugarcane ethanol does not show positive impact on the economy. • Biodiesel and energy efficiency improvements together provide better results. • Food productivity further enhances biodiesel, and energy efficiency impacts

Neutron spectra unfolding with maximum entropy and maximum likelihood

International Nuclear Information System (INIS)

Itoh, Shikoh; Tsunoda, Toshiharu

1989-01-01

A new unfolding theory has been established on the basis of the maximum entropy principle and the maximum likelihood method. This theory correctly embodies the Poisson statistics of neutron detection, and always brings a positive solution over the whole energy range. Moreover, the theory unifies both problems of overdetermined and of underdetermined. For the latter, the ambiguity in assigning a prior probability, i.e. the initial guess in the Bayesian sense, has become extinct by virtue of the principle. An approximate expression of the covariance matrix for the resultant spectra is also presented. An efficient algorithm to solve the nonlinear system, which appears in the present study, has been established. Results of computer simulation showed the effectiveness of the present theory. (author)

Maximum power tracking in WECS (Wind energy conversion systems) via numerical and stochastic approaches

International Nuclear Information System (INIS)

Elnaggar, M.; Abdel Fattah, H.A.; Elshafei, A.L.

2014-01-01

This paper presents a complete design of a two-level control system to capture maximum power in wind energy conversion systems. The upper level of the proposed control system adopts a modified line search optimization algorithm to determine a setpoint for the wind turbine speed. The calculated speed setpoint corresponds to the maximum power point at given operating conditions. The speed setpoint is fed to a generalized predictive controller at the lower level of the control system. A different formulation, that treats the aerodynamic torque as a disturbance, is postulated to derive the control law. The objective is to accurately track the setpoint while keeping the control action free from unacceptably fast or frequent variations. Simulation results based on a realistic model of a 1.5 MW wind turbine confirm the superiority of the proposed control scheme to the conventional ones. - Highlights: • The structure of a MPPT (maximum power point tracking) scheme is presented. • The scheme is divided into the optimization algorithm and the tracking controller. • The optimization algorithm is based on an online line search numerical algorithm. • The tracking controller is treating the aerodynamics torque as a loop disturbance. • The control technique is simulated with stochastic wind speed by Simulink and FAST

Agrification: Agriculture for the industry and energy production

International Nuclear Information System (INIS)

Anon.

1992-01-01

The new aspect of agrification is the production of alternative products, which can replace fossil sources. This substitution is necessary in order to replace hazardous materials and to find a solution for the problem of depletion of conventional energy sources and basic materials. Attention is paid to some developments in Germany: agricultural products for the production of energy, and new industrial applications for vegetable filaments. With regard to energy production from agricultrual products one should distinguish between (a) solid energy sources (biomass), f.e. straw, fast-growing wood, elephant's grass, hay and rapeseed, and (b) fluid and gaseous energy sources, f.e. purified and partly refined rapeseed oil, rapeseed oil methyl-ester (RME), ethanol from sugar beet, methanol from straw and hydrogen from straw and/or elephant's grass. 4 figs., 7 refs

Short-rotation forestry of birch, maple, poplar and willow in Flanders (Belgium) II. Energy production and CO2 emission reduction potential

International Nuclear Information System (INIS)

Walle, Inge van de; Camp, Nancy van; Casteele, Liesbet van de; Verheyen, Kris; Lemeur, Raoul

2007-01-01

Belgium, being an EU country, has committed itself to a 7.5% reduction of greenhouse gas emissions during the first commitment period of the Kyoto Protocol. Within this framework, the Flemish government aims at reaching a share of 6% of renewable electricity in the total electricity production by 2010. In this work, the biomass production of birch, maple, poplar and willow in a short-rotation forestry (SRF) plantation after a 4-year growth period served as the base to calculate the amount of (electrical) energy that could be produced by this type of bioenergy crop in Flanders. The maximum amount of electricity that could be provided by SRF biomass was estimated at 72.9 GWh e year -1 , which only accounts for 0.16% of the total electricity production in this region. Although the energy output was rather low, the bioenergy production process under consideration appeared to be more energy efficient than energy production processes based on fossil fuels. The high efficiency of birch compared to the other species was mainly due to the high calorific value of the birch wood. The maximum CO 2 emission reduction potential of SRF plantations in Flanders was estimated at only 0.09% of the total annual CO 2 emission. The most interesting application of SRF in Flanders seemed to be the establishment of small-scale plantations, linked to a local combined heat and power plant. These plantations could be established on marginal arable soils or on polluted sites, and they could be of importance in the densely populated area of Flanders because of other environmental benefits, among which their function as (temporary) habitat for many species

Decision project related to the energy multi-year 2018/2023 planning (PPE). Evolution of capacities of production of power generating renewable energies: the headlong rush

International Nuclear Information System (INIS)

Perves, Jean-Pierre

2016-01-01

After having recalled that the French government, in its energy multi-year planning for 2018-2023, decided to develop wind and photovoltaic energies at a higher rate, despite their intermittency and the need for back-up nuclear and hydroelectric power plants (which do not emit carbon), and outlined that the power market is now in the torment, in France and in Europe, the author notices that such a development of renewable energies is a matter of concern in Europe, and indicates the objectives defined by the French government for onshore and offshore wind energy and for solar energy. Then, he proposes a critical analysis of the low level scenario of this development, a scenario which the author assesses as not very realistic. A table indicates the status and objectives for all the different renewable energies. The author discusses these values, notices that it is similar to a programme defined by the ADEME. He analyses the 2018/2023 low scenario (production, share, production efficiency, minimum and maximum power) by comparing it with the situation in 2015. He outlines important seasonal variations for wind and solar energy: their production level in winter requires a massive use of other sources. He briefly discusses the perspectives for 2030, and then addresses the development cost in terms of required investments. He discusses the impact of the scenario on greenhouse gas emissions. The appendix provides the official text of the decision project

Promoting greater Federal energy productivity [Final report

Energy Technology Data Exchange (ETDEWEB)

Hopkins, Mark; Dudich, Luther

2003-03-05

This document is a close-out report describing the work done under this DOE grant to improve Federal Energy Productivity. Over the four years covered in this document, the Alliance To Save Energy conducted liaison with the private sector through our Federal Energy Productivity Task Force. In this time, the Alliance held several successful workshops on the uses of metering in Federal facilities and other meetings. We also conducted significant research on energy efficiency, financing, facilitated studies of potential energy savings in energy intensive agencies, and undertook other tasks outlined in this report.

Production processes at extremely high energies

CERN Document Server

Gastmans, R; Wu, Tai Tsun

2013-01-01

The production processes are identified that contribute to the rise of the total cross section in proton-proton scattering at extremely high energies, s->~. At such energies, the scattering can be described by a black disk (completely absorptive) with a radius expanding logarithmically with energy surrounded by a gray fringe (partially absorptive). For the leading term of (lns)^2 in the increasing total cross section, the gray fringe is neglected, and geometrical optics is generalized to production processes. It is known that half of the rise in the total cross section is due to elastic scattering. The other half is found to originate from the production of jets with relatively small momenta in the center-of-mass system.

Wood for energy production. Technology - environment - economy

International Nuclear Information System (INIS)

Serup, H.; Falster, H.; Gamborg, C.

1999-01-01

'Wood for Energy Production', 2nd edition, is a readily understood guide to the application of wood in the Danish energy supply. The first edition was named 'Wood Chips for Energy Production'. It describes the wood fuel from forest to consumer and provides a concise introduction to technological, environmental, and financial matters concerning heating systems for farms, institutions, district heating plants, and CHP plants. The individual sections deal with both conventional, well known technology, as well as the most recent technological advances in the field of CHP production. The purpose of this publication is to reach the largest possible audiance, and it is designed so that the layman may find its background information of special relevance. 'Wood for Energy Production' is also available in German and Danish. (au)

Wood for energy production. Technology - environment - economy

Energy Technology Data Exchange (ETDEWEB)

Serup, H.; Falster, H.; Gamborg, C. [and others

1999-10-01

`Wood for Energy Production`, 2nd edition, is a readily understood guide to the application of wood in the Danish energy supply. The first edition was named `Wood Chips for Energy Production`. It describes the wood fuel from forest to consumer and provides a concise introduction to technological, environmental, and financial matters concerning heating systems for farms, institutions, district heating plants, and CHP plants. The individual sections deal with both conventional, well known technology, as well as the most recent technological advances in the field of CHP production. The purpose of this publication is to reach the largest possible audiance, and it is designed so that the layman may find its background information of special relevance. `Wood for Energy Production` is also available in German and Danish. (au)

Energy efficiency analysis method based on fuzzy DEA cross-model for ethylene production systems in chemical industry

International Nuclear Information System (INIS)

Han, Yongming; Geng, Zhiqiang; Zhu, Qunxiong; Qu, Yixin

2015-01-01

DEA (data envelopment analysis) has been widely used for the efficiency analysis of industrial production process. However, the conventional DEA model is difficult to analyze the pros and cons of the multi DMUs (decision-making units). The DEACM (DEA cross-model) can distinguish the pros and cons of the effective DMUs, but it is unable to take the effect of the uncertainty data into account. This paper proposes an efficiency analysis method based on FDEACM (fuzzy DEA cross-model) with Fuzzy Data. The proposed method has better objectivity and resolving power for the decision-making. First we obtain the minimum, the median and the maximum values of the multi-criteria ethylene energy consumption data by the data fuzzification. On the basis of the multi-criteria fuzzy data, the benchmark of the effective production situations and the improvement directions of the ineffective of the ethylene plants under different production data configurations are obtained by the FDEACM. The experimental result shows that the proposed method can improve the ethylene production conditions and guide the efficiency of energy utilization during ethylene production process. - Highlights: • This paper proposes an efficiency analysis method based on FDEACM (fuzzy DEA cross-model) with data fuzzification. • The proposed method is more efficient and accurate than other methods. • We obtain an energy efficiency analysis framework and process based on FDEACM in ethylene production industry. • The proposed method is valid and efficient in improvement of energy efficiency in the ethylene plants

Energy conservation and maximal entropy production in enzyme reactions.

Science.gov (United States)

Dobovišek, Andrej; Vitas, Marko; Brumen, Milan; Fajmut, Aleš

2017-08-01

A procedure for maximization of the density of entropy production in a single stationary two-step enzyme reaction is developed. Under the constraints of mass conservation, fixed equilibrium constant of a reaction and fixed products of forward and backward enzyme rate constants the existence of maximum in the density of entropy production is demonstrated. In the state with maximal density of entropy production the optimal enzyme rate constants, the stationary concentrations of the substrate and the product, the stationary product yield as well as the stationary reaction flux are calculated. The test, whether these calculated values of the reaction parameters are consistent with their corresponding measured values, is performed for the enzyme Glucose Isomerase. It is found that calculated and measured rate constants agree within an order of magnitude, whereas the calculated reaction flux and the product yield differ from their corresponding measured values for less than 20 % and 5 %, respectively. This indicates that the enzyme Glucose Isomerase, considered in a non-equilibrium stationary state, as found in experiments using the continuous stirred tank reactors, possibly operates close to the state with the maximum in the density of entropy production. Copyright © 2017 Elsevier B.V. All rights reserved.

Grasses for energy production: hydrological guidelines

Energy Technology Data Exchange (ETDEWEB)

Hall, R.L.

2003-07-01

This report provides hydrological guidelines for growers, land and water resource managers, environmental groups and other parties interested in utilising grasses for energy production. The aim of the report is to help interested parties decide if a location is suitable for planting energy grasses by considering whether potential hydrological impacts will have an adverse effect on crop productivity and yield. The guidelines consider: the water use of energy grasses compared with other crops; the factors governing water use; the water requirements for a productive crop; and the likely impacts on the availability and quantity of water. The report points out that there are still gaps in our knowledge of the processes controlling the water use and growth of energy grasses and notes that, in some situations, there will be considerable uncertainty in predictions of water use and the magnitude of the associated hydrological impacts.

Modelling energy consumption in a manufacturing plant using productivity KPIs

Energy Technology Data Exchange (ETDEWEB)

Gallachoir, Brian O.; Cahill, Caiman (Sustainable Energy Research Group, Dept. of Civil and Environmental Engineering, Univ. College Cork (Ireland))

2009-07-01

Energy efficiency initiatives in industrial plants are often focused on getting energy-consuming utilities and devices to operate more efficiently, or on conserving energy. While such device-oriented energy efficiency measures can achieve considerable savings, greater energy efficiency improvement may be achieved by improving the overall productivity and quality of manufacturing processes. The paper highlights the observed relationship between productivity and energy efficiency using aggregated data on unit consumption and production index data for Irish industry. Past studies have developed simple top-down models of final energy consumption in manufacturing plants using energy consumption and production output figures, but these models do not help identify opportunities for energy savings that could achieved through increased productivity. This paper proposes an improved and innovative method of modelling plant final energy demand that introduces standard productivity Key Performance Indicators (KPIs) into the model. The model demonstrates the relationship between energy consumption and productivity, and uses standard productivity metrics to identify the areas of manufacturing activity that offer the most potential for improved energy efficiency. The model provides a means of comparing the effect of device-oriented energy efficiency measures with the potential for improved energy efficiency through increased productivity.

Intelligent Photovoltaic Maximum Power Point Tracking Controller for Energy Enhancement in Renewable Energy System

Directory of Open Access Journals (Sweden)

Subiyanto

2013-01-01

Full Text Available Photovoltaic (PV system is one of the promising renewable energy technologies. Although the energy conversion efficiency of the system is still low, but it has the advantage that the operating cost is free, very low maintenance and pollution-free. Maximum power point tracking (MPPT is a significant part of PV systems. This paper presents a novel intelligent MPPT controller for PV systems. For the MPPT algorithm, an optimized fuzzy logic controller (FLC using the Hopfield neural network is proposed. It utilizes an automatically tuned FLC membership function instead of the trial-and-error approach. The MPPT algorithm is implemented in a new variant of coupled inductor soft switching boost converter with high voltage gain to increase the converter output from the PV panel. The applied switching technique, which includes passive and active regenerative snubber circuits, reduces the insulated gate bipolar transistor switching losses. The proposed MPPT algorithm is implemented using the dSPACE DS1104 platform software on a DS1104 board controller. The prototype MPPT controller is tested using an agilent solar array simulator together with a 3 kW real PV panel. Experimental test results show that the proposed boost converter produces higher output voltages and gives better efficiency (90% than the conventional boost converter with an RCD snubber, which gives 81% efficiency. The prototype MPPT controller is also found to be capable of tracking power from the 3 kW PV array about 2.4 times more than that without using the MPPT controller.

Solar energy; Product information. Zonne-energie; Produktinformatie

Energy Technology Data Exchange (ETDEWEB)

Kruisheer, N

1992-03-20

In five brief articles product information is given on solar energy applications with special attention to the Netherlands. After an introduction on solar energy availability in the Netherlands the developments in solar boiler techniques are dealt with. Solar water heaters have advantages for the environment, and government subsidies stimulate different uses of such water heaters. Also the developments of solar cells show good prospects, not only for developing countries, but also for the industrialized countries. In brief the developments in solar energy storage and the connection of solar equipment to the grid are discussed. Finally attention is paid to the applications of passive solar energy in the housing construction, the use of transparent thermal insulation and the developments of translucent materials. 18 figs., 18 ills.

Energy productivity growth in the Dutch Greenhouse Industry

NARCIS (Netherlands)

Oude Lansink, A.G.J.M.; Ondersteijn, C.J.M.

2006-01-01

Profitability of Dutch greenhouse firms is largely dependent on energy costs, and policy makers focus on reducing the use of energy by these firms. This article uses Russell measures of TE to develop indicators of energy productivity growth. Results show that energy productivity grew by 2.8%

Maximum power point tracking algorithm based on sliding mode and fuzzy logic for photovoltaic sources under variable environmental conditions

Science.gov (United States)

Atik, L.; Petit, P.; Sawicki, J. P.; Ternifi, Z. T.; Bachir, G.; Della, M.; Aillerie, M.

2017-02-01

Solar panels have a nonlinear voltage-current characteristic, with a distinct maximum power point (MPP), which depends on the environmental factors, such as temperature and irradiation. In order to continuously harvest maximum power from the solar panels, they have to operate at their MPP despite the inevitable changes in the environment. Various methods for maximum power point tracking (MPPT) were developed and finally implemented in solar power electronic controllers to increase the efficiency in the electricity production originate from renewables. In this paper we compare using Matlab tools Simulink, two different MPP tracking methods, which are, fuzzy logic control (FL) and sliding mode control (SMC), considering their efficiency in solar energy production.

Energy efficiency and econometric analysis of broiler production farms

International Nuclear Information System (INIS)

Heidari, M.D.; Omid, M.; Akram, A.

2011-01-01

The objective of this study was to determine the energy consumption per 1000 bird for the broiler production in Yazd province, Iran. The data were collected from 44 farms by using a face-to-face questionnaire method during January–February 2010. The collected information was analyzed using descriptive statistics, economic analysis and stochastic frontier production function. The production technology of the farmer was assumed to be specified by the Cobb–Douglas (CD) production function. Total input energy was found to be 186,885.87 MJ (1000 bird) −1 while the output energy was 27,461.21 MJ (1000 bird) −1 . The values of specific energy and energy ratio were calculated at 71.95 MJ kg −1 and 0.15, respectively. The sensitivity of energy inputs was estimated using the marginal physical productivity (MPP) method. The MPP value showed the high impact of human labor and machinery energy inputs on output energy. Returns to scale (RTS) values for broiler were found to be 0.96; thus, there prevailed a decreasing RTS for the estimated model. The net return was found positive, as 1386.53 $ (1000 bird) −1 and the benefit to cost ratio from broiler production was calculated to be 1.38. The study revealed that production of meat was profitable in the studied area. -- Highlights: ► We determined the energy use efficiency (EUE) for the broiler production as 0.15, indicating inefficiency use of energy in these farms. ► Total input and output energies were found to be 186,885.87 MJ (1000 bird) −1 and 27,461.21 MJ (1000 bird) −1 , respectively. ► Cobb–Douglas (CD) frontier production function was found useful in developing econometric model for broiler production. ► The results of budgetary analysis indicate production of meat in broiler farms is profitable in the studied area.

White Paper on Energy Efficiency Status of Energy-Using Products in China (2011)

Energy Technology Data Exchange (ETDEWEB)

Zhou, Nan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Romankiewicz, John [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Fridley, David [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2012-06-01

This White Paper focuses on the areas and products involved in the above tasks, based on the White Paper - Energy Efficiency Status of Energy-Using Products in China (2010), here referred to as “White Paper 2010”, which analyzed the energy efficiency status of 21 typical energy-using products in five sectors: household appliances, office equipment, commercial equipment, industrial equipment, and lighting equipment. Table 1 illustrates the detailed product coverage for this year’s paper, noting the addition of three household appliance items (automatic electric rice cooker, AC electric fan, and household induction cooktop) and one industrial sector item (three-phase distribution transformer).

Self-energy production applied to buildings

Energy Technology Data Exchange (ETDEWEB)

Carlo, Fabricio Ramos del; Balestieri, Jose Antonio Perrella [Sao Paulo State University Julio de Mesquita Filho (UNESP), Guaratingueta, SP (Brazil)], E-mail: perrella@feg.unesp.br; Holanda, Marcelo Rodrigues de [Sao Paulo Univ. (EEL/USP), Lorena, SP (Brazil). Engineering School], E-mail: marcelo@debas.eel.usp.br

2010-07-01

The decentralization of energy production in order to obtain better environmental conditions, reducing greenhouse gas emissions and the cost reduction of electricity and thermal energy consumed in residential buildings has been proposed in the literature. This paper proposes to demonstrate what are the chances of having a microcogeneration system toward the residential application. In this study, we contemplate the technologies involved and their possible inputs that are arranged in a superstructure to be studied. As a first step we obtain the cost of the products generated by the configuration that consists basically of two sources of power generation, and through optimization calculations intended to obtain the best configuration, taking into consideration the selection between four fuels, two equipment generators (Fuel Cell and Internal Combustion Engine)and three levels of energy production for each one. An economic analysis is also presented to evaluate the opportunity of selling the energy generated considering the fluctuations of the residential building consumption needs. (author)

Integration of the nuclear energy among the production facilities of energy in France; Integration de l'energie nucleaire parmi les moyens de production de l'energie en france

Energy Technology Data Exchange (ETDEWEB)

Ailleret, P [Electricite de France (EDF), 75 - Paris (France). Direction des Etudes et Recherches; Taranger, P [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1955-07-01

The present report gives an overview of the present facilities of energy productions in France and their perspectives. the electric production comes for half about power stations hydraulics and for half of thermal power stations. However due to the increase of the energy consumption, France is particularly interested by the atomic energy that appears to bring a supply in due time to the hydraulics and to limit a development of the thermal power stations to which the natural resources of France in classic fuel would not permit to cope presumably. The integration of the nuclear plants to the other production facilities will make itself gradually according to the evolution of the energy needs. (M.B.) [French] Le present rapport donne un apercu des moyens actuels de productions energetiques en France et de ses perspectives. la production electrique provient pour moitie environ de centrales hydraulique et pour moitie de centrales thermiques. Cependant face a l'augmentation de la consommation energetique, la France est tres particulierement interessee par l'energie atomique qui parait devoir apporter en temps utile la releve a l'hydraulique et limiter un developpement des centrales thermiques auxquels les ressources naturelles de la France en combustible classique ne permettraient vraisemblablement pas de faire face. L'integration des centrales nucleaires aux autres moyens de production se fera graduellment en fonction de l'evolution des besoins energetiques. (M.B.)

The Prospects of Rubberwood Biomass Energy Production in Malaysia

Directory of Open Access Journals (Sweden)

Jegatheswaran Ratnasingam

2015-03-01

Full Text Available Rubber has been shown to be one of the most important plantation crops in Malaysia, and rubber tree biomass has widespread applications in almost all sectors of the wood products manufacturing sector. Despite its abundance, the exploitation of rubberwood biomass for energy generation is limited when compared to other available biomass such as oil palm, rice husk, cocoa, sugarcane, coconut, and other wood residues. Furthermore, the use of biomass for energy generation is still in its early stages in Malaysia, a nation still highly dependent on fossil fuels for energy production. The constraints for large scale biomass energy production in Malaysia are the lack of financing for such projects, the need for large investments, and the limited research and development activities in the sector of efficient biomass energy production. The relatively low cost of energy in Malaysia, through the provision of subsidy, also restricts the potential utilization of biomass for energy production. In order to fully realize the potential of biomass energy in Malaysia, the environmental cost must be factored into the cost of energy production.

Department of Energy programs and objectives: energy conservation in agricultural production

Energy Technology Data Exchange (ETDEWEB)

1977-12-01

This document describes the current Department of Energy agriculture research program as it relates to the research recommendations submitted by a 1976 workshop on energy conservation in agricultural production. In-depth discussions on fertilizers, irrigation, crop drying, fuel substitution, crop and animal production systems, greenhouses, materials handling, and transport systems are included. (MCW)

From Policy to Compliance: Federal Energy Efficient Product Procurement

Energy Technology Data Exchange (ETDEWEB)

DeMates, Laurèn [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Scodel, Anna [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2017-09-06

Federal buyers are required to purchase energy-efficient products in an effort to minimize energy use in the federal sector, save the federal government money, and spur market development of efficient products. The Federal Energy Management Program (FEMP)’s Energy Efficient Product Procurement (EEPP) Program helps federal agencies comply with the requirement to purchase energy-efficient products by providing technical assistance and guidance and setting efficiency requirements for certain product categories. Past studies have estimated the savings potential of purchasing energy-efficient products at over $500 million per year in energy costs across federal agencies.1 Despite the strong policy support for EEPP and resources available, energy-efficient product purchasing operates within complex decision-making processes and operational structures; implementation challenges exist that may hinder agencies’ ability to comply with purchasing requirements. The shift to purchasing green products, including energy-efficient products, relies on “buy in” from a variety of potential actors throughout different purchasing pathways. Challenges may be especially high for EEPP relative to other sustainable acquisition programs given that efficient products frequently have a higher first cost than non-efficient ones, which may be perceived as a conflict with fiscal responsibility, or more simply problematic for agency personnel trying to stretch limited budgets. Federal buyers may also face challenges in determining whether a given product is subject to EEPP requirements. Previous analysis on agency compliance with EEPP, conducted by the Alliance to Save Energy (ASE), shows that federal agencies are getting better at purchasing energy-efficient products. ASE conducted two reviews of relevant solicitations for product and service contracts listed on Federal Business Opportunities (FBO), the centralized website where federal agencies are required to post procurements greater

High energy gamma-ray production in nuclear reactions

International Nuclear Information System (INIS)

Pinston, J.A.; Nifenecker, H.; Nifenecker, H.

1989-01-01

Experimental techniques used to study high energy gamma-ray production in nuclear reactions are reviewed. High energy photon production in nucleus-nucleus collisions is discussed. Semi-classical descriptions of the nucleus-nucleus gamma reactions are introduced. Nucleon-nucleon gamma cross sections are considered, including theoretical aspects and experimental data. High energy gamma ray production in proton-nucleus reactions is explained. Theoretical explanations of photon emission in nucleus-nucleus collisions are treated. The contribution of charged pion currents to photon production is mentioned

Energy production and social marginalisation in China

Energy Technology Data Exchange (ETDEWEB)

Philip Andrews-Speed; Xin Ma

2008-05-15

The exploitation and production of primary energy resources and the supply of this energy is critical for China's economic development. Despite the obvious economic benefit to the nation, this energy production has had significant negative socio-economic impacts on certain groups of people at local and national scales. This paper documents three cases of energy production in China and demonstrates that, in each case, marginalisation of social groups has either been created or has been enhanced. These cases are the Three Gorges Dam, the Yumen oilfield, and township and village coal mines. The causes of this marginalisation have their roots in the structures, processes and approaches taken in the making and implementation of national policy in China, and are compounded by poor regulation and monitoring, poor civil rights, and the tension between central and local governments. The government which came to power in 2003 recognised the extent and importance of these social challenges relating to energy production, and has started to take steps to address them.

Study of renewable energy, fuel cell and demotics integration for stationary energy production

Energy Technology Data Exchange (ETDEWEB)

Andaloro, L.; Ferraro, M.; Sergi, F.; Brunaccini, G.; Antonucci, V. [National Research Inst., Messina (Italy)

2009-07-01

This paper described a study in which a small house equipped with various renewable technologies was modelled. The aim of the study was to evaluated the integration of fuel cells with various other energy sources. Technologies installed in the house included a photovoltaic (PV) system; a hydrogen system; fuel cells; a battery-storage system; and a thermal solar panel. Maximum energy savings were evaluated for different configurations and combinations of the installed energy sources. A domotic system was also used to automatically control the use of electrical appliances and improve safety and comfort. An energy side management system was designed and compared with a demand side management system. Various scenarios were simulated in order to test the energy management systems in relation to the automated domotic system.

78 FR 17648 - Energy Conservation Program for Consumer Products: Representative Average Unit Costs of Energy

Science.gov (United States)

2013-03-22

... Conservation Program for Consumer Products: Representative Average Unit Costs of Energy'', dated April 26, 2012... DEPARTMENT OF ENERGY Office of Energy Efficiency and Renewable Energy Energy Conservation Program for Consumer Products: Representative Average Unit Costs of Energy AGENCY: Office of Energy Efficiency...

Centrality and collision system dependence of antiproton production from p+A to Au+Au collisions at AGS energies

International Nuclear Information System (INIS)

Sako, H.; Ahle, L.; Akiba, Y.

1997-12-01

Antiproton production in heavy ion collisions reflects subtle interplay between initial production and absorption by nucleons. Because the AGS energies (10--20 A·GeV/c) are close to the antiproton production threshold, antiproton may be sensitive to cooperative processes such as QGP and hadronic multi-step processes. On the other hand, antiproton has been proposed as a probe of baryon density due to large N anti N annihilation cross sections. Cascade models predict the maximum baryon density reaches about 10 times the normal nucleus density in central Au+Au collisions, where the strong antiproton absorption is expected. In this paper, the authors show systematic studies of antiproton production from p+A to Au+Au collisions

Prospects for dedicated energy crop production and attitudes towards agricultural straw use: The case of livestock farmers

International Nuclear Information System (INIS)

Wilson, P.; Glithero, N.J.; Ramsden, S.J.

2014-01-01

Second generation biofuels utilising agricultural by-products (e.g. straw), or dedicated energy crops (DECs) produced on ‘marginal’ land, have been called for. A structured telephone survey of 263 livestock farmers, predominantly located in the west or ‘marginal’ upland areas of England captured data on attitudes towards straw use and DECs. Combined with farm physical and business data, the survey results show that 7.2% and 6.3% of farmers would respectively consider growing SRC and miscanthus, producing respective maximum potential English crop areas of 54,603 ha and 43,859 ha. If higher market prices for straw occurred, most livestock farmers would continue to buy straw. Reasons for not being willing to consider growing DECs include concerns over land quality, committing land for a long time period, lack of appropriate machinery, profitability, and time to financial return; a range of moral, land quality, production conflict and lack of crop knowledge factors were also cited. Results demonstrate limited potential for the production of DECs on livestock farms in England. Changes in policy support to address farmer concerns with respect to DECs will be required to incentivise farmers to increase energy crop production. Policy support for DEC production must be cognisant of farm-level economic, tenancy and personal objectives. - Highlights: • Survey of English livestock farms determining attitudes to dedicated energy crops. • 6.3% to 7.2% of surveyed farmers would consider growing energy crops. • Limited potential for dedicated energy crops on livestock farms in England. • Livestock farmers would continue to buy straw, even at higher market prices. • Wide range of reasons given for farmers’ decisions related to energy crops

Energy-Performance as a driver for optimal production planning

International Nuclear Information System (INIS)

Salahi, Niloofar; Jafari, Mohsen A.

2016-01-01

Highlights: • A 2-dimensional Energy-Performance measure is proposed for energy aware production. • This is a novel approach integrates energy efficiency with production requirements. • This approach simultaneously incorporates machine and process related specifications. • The problem is solved as stochastic MILP with constraints addressing risk averseness. • The optimization is illustrated for 2 cases of single and serial machining operation. • Impact of various electricity pricing schemes on proposed production plan is analyzed. - Abstract: In this paper, we present energy-aware production planning using a two-dimensional “Energy-Performance” measure. With this measure, the production plan explicitly takes into account machine-level requirements, process control strategies, product types and demand patterns. The “Energy-Performance” measure is developed based on an existing concept, namely, “Specific Energy” at machine level. It is further expanded to an “Energy-Performance” profile for a production line. A production planning problem is formulated as a stochastic MILP with risk-averse constraints to account for manufacturer’s risk averseness. The objective is to attain an optimal production plan that minimizes the total loss distribution subject to system throughput targets, probabilistic risk constraints and constraints imposed by the underlying “Energy-Performance” pattern. Electricity price and demand per unit time are assumed to be stochastic. Conditional Value at Risk (CVaR) of loss distributions is used as the manufacturer’s risk measure. Both single-machine and production lines are studied for different profiles and electricity pricing schemes. It is shown that the shape of “Energy-Performance” profile can change optimal plans.

Macro-level integrated renewable energy production schemes for sustainable development

International Nuclear Information System (INIS)

Subhadra, Bobban G.

2011-01-01

The production of renewable clean energy is a prime necessity for the sustainable future existence of our planet. However, because of the resource-intensive nature, and other challenges associated with these new generation renewable energy sources, novel industrial frameworks need to be co-developed. Integrated renewable energy production schemes with foundations on resource sharing, carbon neutrality, energy-efficient design, source reduction, green processing plan, anthropogenic use of waste resources for the production green energy along with the production of raw material for allied food and chemical industries is imperative for the sustainable development of this sector especially in an emission-constrained future industrial scenario. To attain these objectives, the scope of hybrid renewable production systems and integrated renewable energy industrial ecology is briefly described. Further, the principles of Integrated Renewable Energy Park (IREP) approach, an example for macro-level energy production, and its benefits and global applications are also explored. - Research highlights: → Discusses the need for macro-level renewable energy production schemes. → Scope of hybrid and integrated industrial ecology for renewable energy production. → Integrated Renewable Energy Parks (IREPs): A macro-level energy production scheme. → Discusses the principle foundations and global applications of IREPs. → Describes the significance of IREPs in the carbon-neutral future business arena.

Energy and environmental implications of copper production

Energy Technology Data Exchange (ETDEWEB)

Alvardo, Sergio [Chile Univ., Dept. of Mechanical Engineering, Santiago (Chile); Maldonado, Pedro; Jaques, Ivan [Chile Univ., Energy Research Program, Santiago (Chile)

1999-04-01

Primary copper production is a major activity in the mining sector. It is highly energy-intensive, ranking third in specific energy consumption (SEC) among the five major basic metals (aluminum, copper, iron, lead and zinc) and poses important environmental hazards. We examine the large discrepancy between theoretical (from thermodynamics) and actual (from empirical data) SECs and then describe relevant environmental issues, focusing on the most significant energy-related environmental impacts of primary copper production with emphasis on greenhouse-gas (GHG) emissions. An example of GHG energy-related abatement that concurrently improves energy use is presented. (Author)

Long-term affected energy production of waste to energy technologies identified by use of energy system analysis.

Science.gov (United States)

Münster, M; Meibom, P

2010-12-01

Affected energy production is often decisive for the outcome of consequential life-cycle assessments when comparing the potential environmental impact of products or services. Affected energy production is however difficult to determine. In this article the future long-term affected energy production is identified by use of energy system analysis. The focus is on different uses of waste for energy production. The Waste-to-Energy technologies analysed include co-combustion of coal and waste, anaerobic digestion and thermal gasification. The analysis is based on optimization of both investments and production of electricity, district heating and bio-fuel in a future possible energy system in 2025 in the countries of the Northern European electricity market (Denmark, Norway, Sweden, Finland and Germany). Scenarios with different CO(2) quota costs are analysed. It is demonstrated that the waste incineration continues to treat the largest amount of waste. Investments in new waste incineration capacity may, however, be superseded by investments in new Waste-to-Energy technologies, particularly those utilising sorted fractions such as organic waste and refuse derived fuel. The changed use of waste proves to always affect a combination of technologies. What is affected varies among the different Waste-to-Energy technologies and is furthermore dependent on the CO(2) quota costs and on the geographical scope. The necessity for investments in flexibility measures varies with the different technologies such as storage of heat and waste as well as expansion of district heating networks. Finally, inflexible technologies such as nuclear power plants are shown to be affected. Copyright © 2010 Elsevier Ltd. All rights reserved.

Periodic variations of Auger energy maximum distribution following He2+ + H2 collisions: A complete analogy with photon interferences

International Nuclear Information System (INIS)

Cholet, M.; Minerbe, F.; Oliviero, G.; Pestel, V.; Frémont, F.

2014-01-01

Highlights: • Young type interferences with electrons are revisited. • Oscillations in the angular distribution of the energy maximum of Auger spectra are evidenced. • Model calculations are in good agreement with the experimental result. • The position of the Auger spectra oscillates in counterphase with the total intensity. - Abstract: In this article, we present experimental evidence of a particular electron-interference phenomenon. The electrons are provided by autoionization of 2l2l′ doubly excited He atoms following the capture of H 2 electrons by a slow He 2+ incoming ion. We observe that the position of the energy maximum of the Auger structures oscillates with the detection angle. Calculation based on a simple model that includes interferences clearly shows that the present oscillations are due to Young-type interferences caused by electrons scattering on both H + centers

IEA Energy Technology Essentials: Biofuel Production

Energy Technology Data Exchange (ETDEWEB)

NONE

2007-01-15

The IEA Energy Technology Essentials series offers concise four-page updates on the different technologies for producing, transporting and using energy. Biofuel Production is the topic covered in this edition.

Expected energy production evaluation for photovoltaic systems

DEFF Research Database (Denmark)

Ding, Yi; Østergaard, Jacob; Peng, Wang

2011-01-01

A photovoltaic (PV) system consists of many solar panels, which are connected in series, parallel or a combination of both. Energy production for the PV system with various configurations is different. In this paper, a methodology is developed to evaluate and analyze the expected energy production...

The mechanics of granitoid systems and maximum entropy production rates.

Science.gov (United States)

Hobbs, Bruce E; Ord, Alison

2010-01-13

A model for the formation of granitoid systems is developed involving melt production spatially below a rising isotherm that defines melt initiation. Production of the melt volumes necessary to form granitoid complexes within 10(4)-10(7) years demands control of the isotherm velocity by melt advection. This velocity is one control on the melt flux generated spatially just above the melt isotherm, which is the control valve for the behaviour of the complete granitoid system. Melt transport occurs in conduits initiated as sheets or tubes comprising melt inclusions arising from Gurson-Tvergaard constitutive behaviour. Such conduits appear as leucosomes parallel to lineations and foliations, and ductile and brittle dykes. The melt flux generated at the melt isotherm controls the position of the melt solidus isotherm and hence the physical height of the Transport/Emplacement Zone. A conduit width-selection process, driven by changes in melt viscosity and constitutive behaviour, operates within the Transport Zone to progressively increase the width of apertures upwards. Melt can also be driven horizontally by gradients in topography; these horizontal fluxes can be similar in magnitude to vertical fluxes. Fluxes induced by deformation can compete with both buoyancy and topographic-driven flow over all length scales and results locally in transient 'ponds' of melt. Pluton emplacement is controlled by the transition in constitutive behaviour of the melt/magma from elastic-viscous at high temperatures to elastic-plastic-viscous approaching the melt solidus enabling finite thickness plutons to develop. The system involves coupled feedback processes that grow at the expense of heat supplied to the system and compete with melt advection. The result is that limits are placed on the size and time scale of the system. Optimal characteristics of the system coincide with a state of maximum entropy production rate. This journal is © 2010 The Royal Society

Energy productivity and efficiency of wheat farming in Bangladesh

International Nuclear Information System (INIS)

Rahman, Sanzidur; Hasan, M. Kamrul

2014-01-01

Wheat is the second most important cereal crop in Bangladesh and production is highly sensitive to variations in the environment. We estimate productivity and energy efficiency of wheat farming in Bangladesh by applying a stochastic production frontier approach while accounting for the environmental constraints affecting production. Wheat farming is energy efficient with a net energy balance of 20,596 MJ per ha and energy ratio of 2.34. Environmental constraints such as a combination of unsuitable land, weed and pest attack, bad weather, planting delay and infertile soils significantly reduce wheat production and its energy efficiency. Environmental constraints account for a mean energy efficiency of 3 percentage points. Mean technical efficiency is 88% thereby indicating that elimination of inefficiencies can increase wheat energy output by 12%. Farmers' education, access to agricultural information and training in wheat production significantly improves efficiency, whereas events such as a delay in planting and first fertilization significantly reduce it. Policy recommendations include development of varieties that are resistant to environmental constraints and suitable for marginal areas; improvement of wheat farming practices; and investments in education and training of farmers as well as dissemination of information. - Highlights: • Bangladesh wheat farming is energy efficient at 20,596 MJha −1 ; energy ratio 2.34. • Environmental factors significantly influence productivity and energy efficiency. • Environmental factors must be taken into account when estimating wheat productivity. • Government policies must focus on ways of alleviating environmental factors. • Farmers' education, training and information sources increase technical efficiency

Water for energy and fuel production

CERN Document Server

Shah, Yatish T

2014-01-01

Water, in all its forms, may be the key to an environmentally friendly energy economy. Water is free, there is plenty of it, plus it carries what is generally believed to be the best long-term source of green energy-hydrogen. Water for Energy and Fuel Production explores the many roles of water in the energy and fuel industry. The text not only discusses water's use as a direct source of energy and fuel-such as hydrogen from water dissociation, methane from water-based clathrate molecules, hydroelectric dams, and hydrokinetic energy from tidal waves, off-shore undercurrents, and inland waterways-but also: Describes water's benign application in the production of oil, gas, coal, uranium, biomass, and other raw fuels, and as an energy carrier in the form of hot water and steam Examines water's role as a reactant, reaction medium, and catalyst-as well as steam's role as a reactant-for the conversion of raw fuels to synthetic fuels Explains how supercritical water can be used to convert fossil- and bio-based feed...

Maximum Recoverable Gas from Hydrate Bearing Sediments by Depressurization

KAUST Repository

Terzariol, Marco

2017-11-13

The estimation of gas production rates from hydrate bearing sediments requires complex numerical simulations. This manuscript presents a set of simple and robust analytical solutions to estimate the maximum depressurization-driven recoverable gas. These limiting-equilibrium solutions are established when the dissociation front reaches steady state conditions and ceases to expand further. Analytical solutions show the relevance of (1) relative permeabilities between the hydrate free sediment, the hydrate bearing sediment, and the aquitard layers, and (2) the extent of depressurization in terms of the fluid pressures at the well, at the phase boundary, and in the far field. Close form solutions for the size of the produced zone allow for expeditious financial analyses; results highlight the need for innovative production strategies in order to make hydrate accumulations an economically-viable energy resource. Horizontal directional drilling and multi-wellpoint seafloor dewatering installations may lead to advantageous production strategies in shallow seafloor reservoirs.

Green energy criteria and life cycle assessment in assessing environmental competitiveness of energy products

International Nuclear Information System (INIS)

Maelkki, H.; Hongisto, M.; Turkulainen, T.; Kuisma, J.; Loikkanen, T.

1999-01-01

The liberalisation of energy markets has increased the need to enlarge the information base of fuel chains, to evaluate the environmental quality of energy products transparently and to communicate results in a credible way. The preparedness of energy purchasers, producers and sellers to support energy choices of their customers and to meet the information requirements of various stake holders can be strengthened. The environmental impacts related to energy products are turning into a significant dimension of competitiveness. Possibilities to promote market-driven environmental protection mechanisms and to construct incentives, which cover the whole energy production system exist and can be supported. Knowledge of environmental impacts of various energy products can be increased by means of several supplementary instruments like eco-profiles, environmental labels and life cycle assessments of products. Life cycle assessment forms a systematic basis of information, which supports the environmental communications directed to various stake holders. In this study selected public LCA-studies concerning energy production have been compared, criteria of green energy have been charted and their outlook has been assessed. In addition the development of an LCA- based relative environmental performance indicator system, which supports various transparent comparisons, has been outlined. The mapping of methodological differences of published LCA-studies regarding various energy alternatives proves, that there is differences e.g. in allocation principles, system boundaries, and age of source information and in many other details. These discrepancies should be known, because they also affect the results. That is why the use of available LCA studies as a basis for comparative assertions may be problematic. The renewability of an energy source is a threshold requirement in eco-energy criteria formulated and introduced by Finnish, Swedish and Norwegian nature conservation

A novel minimum cost maximum power algorithm for future smart home energy management.

Science.gov (United States)

Singaravelan, A; Kowsalya, M

2017-11-01

With the latest development of smart grid technology, the energy management system can be efficiently implemented at consumer premises. In this paper, an energy management system with wireless communication and smart meter are designed for scheduling the electric home appliances efficiently with an aim of reducing the cost and peak demand. For an efficient scheduling scheme, the appliances are classified into two types: uninterruptible and interruptible appliances. The problem formulation was constructed based on the practical constraints that make the proposed algorithm cope up with the real-time situation. The formulated problem was identified as Mixed Integer Linear Programming (MILP) problem, so this problem was solved by a step-wise approach. This paper proposes a novel Minimum Cost Maximum Power (MCMP) algorithm to solve the formulated problem. The proposed algorithm was simulated with input data available in the existing method. For validating the proposed MCMP algorithm, results were compared with the existing method. The compared results prove that the proposed algorithm efficiently reduces the consumer electricity consumption cost and peak demand to optimum level with 100% task completion without sacrificing the consumer comfort.

Microalgal cultivation and utilization in sustainable energy production

Energy Technology Data Exchange (ETDEWEB)

Lakaniemi, A.-M.

2012-07-01

Microalgae are a promising feedstock for biofuel and bioenergy production due to their high photosynthetic efficiencies, high growth rates and no need for external organic carbon supply. However, microalgal biomass cultivation for energy production purposes is still rare in commercial scale. Further research and development is needed to make microalgal derived energy sustainable and economically competitive. This work investigated cultivation of fresh water microalga Chlorella vulgaris and marine microalga Dunaliella tertiolecta and their utilization in production of hydrogen, methane, electricity, butanol and bio-oil after bulk harvesting the biomass. Growth of the two microalgae was studied in five different photobioreactor (PBR) configurations especially concentrating on the quantification and characterization of heterotrophic bacteria in non-axenic microalgal cultivations and microalgal utilization of different nitrogen sources. Anaerobic cultures used for the energy conversion processes were enriched from a mesophilic municipal sewage digester separately for production of H{sub 2}, CH{sub 4} and electricity from the two microalgal species. After culture enrichment, energy conversion yields of microalgal biomass to the different energy carriers were compared. In summary, this study demonstrated that both C. vulgaris and D. tertiolecta can be used for production of Hv(2), CHv(4), electricity, butanol and lipids. Based on this study C. vulgaris is more suitable for bioenergy production than D. tertiolecta. Depending on cellular lipid content, lipid utilization for bio-oil production and anaerobic digestion were the most potent means of converting C. vulgaris biomass to energy. The study also revealed diverse microbial communities in non-axenic microalgal photobioreactor cultures and in anaerobic consortia converting microalgal biomass to energy carriers

Energy for Tomorrow's World - Acting Now

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-06-01

WEC, with over 75 years of history, is concentrating on study and research about production and utilization of sustainable energy and regional and technology program for the maximum benefit of human beings. WEC is a global multi energy organization with supports from private companies, public corporations, governments, academics and famous people in around one hundred countries. The activities of WEC include major energy production and consumption market. 18 figs., 17 tabs.

Energy condensed packaged systems. Composition, production, properties

Directory of Open Access Journals (Sweden)

Igor L. Kovalenko

2015-03-01

Full Text Available In this paper it is presented the substantiation of choice of fuel phase composition and optimal technology of emulsion production on the basis of binary solution of ammonium and calcium nitrates, which provide the obtaining of energy condensed packaged systems with specified properties. The thermal decomposition of energy condensed systems on the basis of ammonium nitrate is investigated. It is shown that the fuel phase of emulsion systems should be based on esters of polyunsaturated acids or on combinations thereof with petroleum products. And ceresin or petroleum wax can be used as the structuring additive. The influence of the technology of energy condensed systems production on the physicochemical and detonation parameters of emulsion explosives is considered. It is shown the possibility of obtaining of emulsion systems with dispersion of 1.3...1.8 microns and viscosity higher than 103 Pa∙s in the apparatus of original design. The sensitizing effect of chlorinated paraffin CP-470 on the thermolysis of energy condensed emulsion system is shown. The composition and production technology of energy condensed packaged emulsion systems of mark Ukrainit-P for underground mining in mines not dangerous on gas and dust are developed.

Automatic control algorithm effects on energy production

Science.gov (United States)

Mcnerney, G. M.

1981-01-01

A computer model was developed using actual wind time series and turbine performance data to simulate the power produced by the Sandia 17-m VAWT operating in automatic control. The model was used to investigate the influence of starting algorithms on annual energy production. The results indicate that, depending on turbine and local wind characteristics, a bad choice of a control algorithm can significantly reduce overall energy production. The model can be used to select control algorithms and threshold parameters that maximize long term energy production. The results from local site and turbine characteristics were generalized to obtain general guidelines for control algorithm design.

Assessment of environmental external effects in the production of energy

DEFF Research Database (Denmark)

Schleisner, L.; Meyer, H.J.; Morthorst, P.E.

1995-01-01

A project in Denmark has been carried out with the purpose to assess the environmental damages and the external costs in the production of energy. The energy production technologies that will be reported in this paper are wind power and a conventional coal fired plant. In the project the environm......A project in Denmark has been carried out with the purpose to assess the environmental damages and the external costs in the production of energy. The energy production technologies that will be reported in this paper are wind power and a conventional coal fired plant. In the project...... the environmental damages for the energy production technologies are compared, and externalities in the production of energy using renewable energy and fossil fuels are identified, estimated and monetized....

Electrorheology for energy production and conservation

Science.gov (United States)

Huang, Ke

Recently, based on the physics of viscosity, we developed a new technology, which utilizes electric or magnetic fields to change the rheology of complex fluids to reduce the viscosity, while keeping the temperature unchanged. The method is universal and applicable to all complex fluids with suspended particles of nano-meter, submicrometer, or micrometer size. Completely different from the traditional viscosity reduction method, raising the temperature, this technology is energy-efficient, as it only requires small amount of energy to aggregate the suspended particles. In this thesis, we will first discuss this new technology in detail, both in theory and practice. Then, we will report applications of our technology to energy science research. Presently, 80% of all energy sources are liquid fuels. The viscosity of liquid fuels plays an important role in energy production and energy conservation. With an electric field, we can reduce the viscosity of asphalt-based crude oil. This is important and useful for heavy crude oil and off-shore crude oil production and transportation. Especially, since there is no practical way to raise the temperature of crude oil inside the deepwater pipelines, our technology may play a key role in future off-shore crude oil production. Electrorehology can also be used to reduce the viscosity of refinery fuels, such as diesel fuel and gasoline. When we apply this technology to fuel injection, the fuel droplets in the fuel atomization become smaller, leading to faster combustion in the engine chambers. As the fuel efficiency of internal combustion engines depends on the combustion speed and timing, the fast combustion produces much higher fuel efficiency. Therefore, adding our technology on existing engines improves the engine efficiency significantly. A theoretical model for the engine combustion, which explains how fast combustion improves the engine efficiency, is also presented in the thesis. As energy is the key to our national

ENERGY USE ANALYSIS FOR RICE PRODUCTION IN NASARAWA STATE, NIGERIA

Directory of Open Access Journals (Sweden)

Hussaini Yusuf Ibrahim

2012-12-01

Full Text Available The study was conducted to analyze energy use for in rice production in Nasarawa state Nigeria using a sample of 120 randomly selected rice farmers. Energy productivity, energy efficiency and specific energy were computed and simple descriptive statistics was used for data analysis. The energy use pattern shows that, rice production consumed an average total energy of 12906.8 MJha-1, with herbicide energy input contributing the largest share (53.55 %. Human labour had the least share (0.74 % of the total energy input used. The energy productivity, Specific energy and energy efficiency were 0.3 MJ-1, 3.6 MJ-1 and 4.1 respectively. A total of 10925.0 MJ of energy was used in the form of indirect energy and 1981.8MJ was in the direct form of energy. Non-renewable energy forms contributed the largest share (80.63 % of the total energy input used for rice production in the study area. Rice production in the study area was observed to be mainly dependent on non-renewable and indirect energy input especially herbicide. Thus, the study recommends the introduction of integrated weed management system in order to reduce cost and dependence on a non-renewable input for weed control.

Effects of Pyrolysis Temperature on Product Yields and Energy Recovery from Co-Feeding of Cotton Gin Trash, Cow Manure, and Microalgae: A Simulation Study

Science.gov (United States)

Hanif, Muhammad Usman; Capareda, Sergio C.; Iqbal, Hamid; Arazo, Renato Ortiz; Baig, Muhammad Anwar

2016-01-01

The intensive search of new and cleaner energy catches interest in recent years due to huge consumption of fossil fuels coupled with the challenge of energy and environmental sustainability. Production of renewable and environmentally benign energy from locally available raw materials is coming in the frontline. In this work, conversion of the combined biomass (cotton gin trash, cow manure, and Microalgae [Nannochloropsis oculata]) through batch pyrolysis has been investigated. The effect of temperature to the production of energy fuels such as bio-oil, char, and biogas have been simulated considering the yield and energy content as responses. Result of the investigation generally revealed that the proportions of the different biomass did not significantly affect the product yield and energy recovery. Significant effect of temperature is evident in the simulation result of energy recovery whereby maximum conversion was achieved at 400°C for char (91 wt%), 600°C for syngas (22 wt%), and 551°C for bio-oil (48 wt%). Overall energy conversion efficiency of 75.5% was obtained at 589°C in which 15.6 MJ/kg of mixed biomass will be elevated to pyrolysis products. PMID:27043929

The impact of future energy demand on renewable energy production – Case of Norway

International Nuclear Information System (INIS)

Rosenberg, Eva; Lind, Arne; Espegren, Kari Aamodt

2013-01-01

Projections of energy demand are an important part of analyses of policies to promote conservation, efficiency, technology implementation and renewable energy production. The development of energy demand is a key driver of the future energy system. This paper presents long-term projections of the Norwegian energy demand as a two-step methodology of first using activities and intensities to calculate a demand of energy services, and secondly use this as input to the energy system model TIMES-Norway to optimize the Norwegian energy system. Long-term energy demand projections are uncertain and the purpose of this paper is to illustrate the impact of different projections on the energy system. The results of the analyses show that decreased energy demand results in a higher renewable fraction compared to an increased demand, and the renewable energy production increases with increased energy demand. The most profitable solution to cover increased demand is to increase the use of bio energy and to implement energy efficiency measures. To increase the wind power production, an increased renewable target or higher electricity export prices have to be fulfilled, in combination with more electricity export. - Highlights: • Projections to 2050 of Norwegian energy demand services, carriers and technologies. • Energy demand services calculated based on intensities and activities. • Energy carriers and technologies analysed by TIMES-Norway. • High renewable target results in more wind power production and electricity export. • Increased energy efficiency is important for a high renewable fraction

Energy Production System Management - Renewable energy power supply integration with Building Automation System

International Nuclear Information System (INIS)

Figueiredo, Joao; Martins, Joao

2010-01-01

Intelligent buildings, historically and technologically, refers to the integration of four distinctive systems: Building Automation Systems (BAS), Telecommunication Systems, Office Automation Systems and Computer Building Management Systems. The increasing sophisticated BAS has become the 'heart and soul' of modern intelligent buildings. Integrating energy supply and demand elements - often known as Demand-Side Management (DSM) - has became an important energy efficiency policy concept. Nowadays, European countries have diversified their power supplies, reducing the dependence on OPEC, and developing a broader mix of energy sources maximizing the use of renewable energy domestic sources. In this way it makes sense to include a fifth system into the intelligent building group: Energy Production System Management (EPSM). This paper presents a Building Automation System where the Demand-Side Management is fully integrated with the building's Energy Production System, which incorporates a complete set of renewable energy production and storage systems.

THE RENEWABLE ENERGY PRODUCTION-ECONOMIC DEVELOPMENT NEXUS

Directory of Open Access Journals (Sweden)

Gorkemli Kazar

2014-04-01

Full Text Available As renewable energy requirements increases, its relation with development is controversial. In this study, by taking human development index for development level, the relationship between renewable electricity net generation values and development has been searched with panel analysis. Study covers two different time periods: 1980-2010 with 5 year data to analyze long term effects and 2005-2010 yearly data for short term effects. Unlike previous studies, energy generation has been taken into consideration for it is thought to be more related with economic development. It is found that in the long run economic development will be leading to renewable energy production, while in the short run there exists a bidirectional causal relationship between renewable energy production and economic development. In addition, the causal relationship between economic development and renewable energy production varies both in the long run and in the short run due to human development level of the countries.

ENERGY SAVING RESERVES IN THE PRODUCTION OF FEED ADDITIVES WITH THE SPECIFIED GRANULOMETRIC COMPOSITION

Directory of Open Access Journals (Sweden)

A. A. Shevtsov

2015-01-01

Full Text Available Due to the growing need to substitute expensive foreign-made feed products need for expanding food resources in the Russian market appears. The disadvantages of existing technological lines for the preparation of mineral feed additives are high specific energy consumption, low economic efficiency and inadequate conditions for environmental safety insuring. That is why energy-efficient production method for the feed additive based on zeolite and a technological line for its realization was developed at the Department of Technology of bread, pastry, pasta and grain processing industries in VSUET. Application of refrigeration unit operating in heat pump mode allows preparation of heat transfer agents with a maximum utilization of secondary heat sources. After drying the spent drying agent is fed to the preheating methioninate copper suspension through the regenerative heat exchange, then to the dehumidification into the evaporator of refrigeration unit and then it is returned to the first section of the two-part condenser in closed-loop mode. Feed fat is heated to 55 ... 60 ° C, by "hot water", heating of which takes place in the second section of the 11th condenser to the temperature of 70 ... 75 ° C and is fed into the jacket of fat melting device. Then it is returned to the second capacitor section to form a recirculation loop. We developed a feed additive with the following particle size distribution: a large fraction of 2.8%, the average fraction of 95.2%, the fine fraction of 2.0%, the residue on the sieve with a mesh № 1,2 of 2,0%, with a moisture content of 6.2%, the angle of repose of 42 deg., dispersibility of 6.9%, a bulk density of 385 kg / m3. The proposed method for the production of the feed additive based on zeolite ensures environmental safety of production due to closed recirculation circuits on material and energy flows, helps to reduce energy and resource consumption for the production of the feed additive, to obtain high

Maximum pseudorapidity gap analysis in nuclear interaction from a few GeV to few hundred GeV

International Nuclear Information System (INIS)

Ghosh, Dipak; Deb, Argha; Haldar, Prabir Kumar; Sahoo, Swarup Ranjan

2002-01-01

In the study of multiparticle production two important parameters are usually investigated - pseudorapidity distribution of pions and pseudorapidity gap distribution. This communication presents all study on maximum pseudorapidity gap distribution in case of nucleus nucleus collision in approximately entire accelerator energy available (4.5 - 200 AGeV)

Correlation between blister skin thickness, the maximum in the damage-energy distribution, and projected ranges of He+ ions in metals: V

International Nuclear Information System (INIS)

Kaminsky, M.; Das, S.K.; Fenske, G.

1976-01-01

In these experiments a systematic study of the correlation of the skin thickness measured directly by scanning electron microscopy with both the calculated projected-range values and the maximum in the damage-energy distribution has been conducted for a broad helium-ion energy range (100 keV-1000 keV in polycrystalline vanadium. (Auth.)

Study of the renewable energy potential and development in Alsace

International Nuclear Information System (INIS)

2016-01-01

This report is part of a study which aimed at assessing the possibility of a renewable energy production equal to or greater than Alsace energy production between 2020 and 2050. It comprised an analysis of potentials and deadlocks for the development of each renewable energy. After an overview of renewable energy production by the end of 2012, the report addresses the different sectors (solar, biomass fuel, geothermal, heat recovery, aero-thermal, wind, hydroelectricity, methanization, agricultural fuels, transports). For each of them, it proposes assessments for the different specific technical resources and processes. Then, after a synthesis of the obtained maximum theoretical resources, it reports the development of three scenarios (a trend-based one, a maximum one, and a proactive one) while addressing each resource within them

Emf, maximum power and efficiency of fuel cells

International Nuclear Information System (INIS)

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

1990-01-01

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

Carbon and nitrogen trade-offs in biomass energy production

Energy Technology Data Exchange (ETDEWEB)

Cucek, Lidija; Klemes, Jiri Jaromir [University of Pannonia, Centre for Process Integration and Intensification (CPI" 2), Research Institute of Chemical and Process Engineering, Faculty of Information Technology, Veszprem (Hungary); Kravanja, Zdravko [University of Maribor, Faculty of Chemistry and Chemical Engineering, Maribor (Slovenia)

2012-06-15

This contribution provides an overview of carbon (CFs) and nitrogen footprints (NFs) concerning their measures and impacts on the ecosystem and human health. The adversarial relationship between them is illustrated by the three biomass energy production applications, which substitute fossil energy production applications: (i) domestic wood combustion where different fossil energy sources (natural gas, coal, and fuel oil) are supplemented, (ii) bioethanol production from corn grain via the dry-grind process, where petrol is supplemented, and (iii) rape methyl ester production from rape seed oil via catalytic trans-esterification, where diesel is supplemented. The life cycle assessment is applied to assess the CFs and NFs resulting from different energy production applications from 'cradle-to-grave' span. The results highlighted that all biomass-derived energy generations have lower CFs and higher NFs whilst, on the other hand, fossil energies have higher CFs and lower NFs. (orig.)

Energy production, conversion, storage, conservation, and coupling

CERN Document Server

Demirel, Yaşar

2012-01-01

Understanding the sustainable use of energy in various processes is an integral part of engineering and scientific studies, which rely on a sound knowledge of energy systems. Whilst many institutions now offer degrees in energy-related programs, a comprehensive textbook, which introduces and explains sustainable energy systems and can be used across engineering and scientific fields, has been lacking. Energy: Production, Conversion, Storage, Conservation, and Coupling provides the reader with a practical understanding of these five main topic areas of energy including 130 examples and over 600 practice problems. Each chapter contains a range of supporting figures, tables, thermodynamic diagrams and charts, while the Appendix supplies the reader with all the necessary data including the steam tables. This new textbook presents a clear introduction of basic vocabulary, properties, forms, sources, and balances of energy before advancing to the main topic areas of: • Energy production and conversion in importa...

Environmental consequences of energy production: Proceedings

Energy Technology Data Exchange (ETDEWEB)

none,

1989-01-01

The Seventeenth Annual Illinois Energy conference entitled Environmental consequences of Energy Production was held in Chicago, Illinois on October 19-20, 1989. The purpose of the meeting was to provide a forum for exchange of information on the technical, economic and institutional issues surrounding energy production and related environmental problems. The conference program was developed by a planning committee which included Illinois energy and environmental specialists from the major sectors including energy industries, environmental organizations, research universities, utility companies, federal, state and local government agencies, and public interest groups. The conference included presentations on four major topic areas. The issue areas were: urban pollution: where are we now and what needs to be done in the future; the acid rain problem: implications of proposed federal legislation on the Midwest; global warming: an update on the scientific debate; and strategies to minimize environmental damage. Separate abstracts have been prepared for the individual presentations. (FL)

Energy use pattern analyses of greenhouse vegetable production

Energy Technology Data Exchange (ETDEWEB)

Canakci, M.; Akinci, I. [Department of Agricultural Machinery, Faculty of Agriculture, Akdeniz University, 07070 Antalya (Turkey)

2006-07-15

Greenhouse farming is a growing industry in many states. It is a very expensive way to produce greenhouse crops and there are many variables to consider before the farmer decides to take this route. A good location is essential for crop planning and growing. However, current studies related to energy use patterns and resources present in vegetable production are very limited. This research attempts to investigate the energy use patterns in greenhouse vegetable production, to determine the energy output-input ratio and their relationships. Antalya province, which has greenhouse area of about 13,337ha (30.2%), is the center of greenhouse farming in Turkey. A questionnaire was distributed to 101 greenhouse farms from 11 villages in order to obtain the available data for vegetable production. Power requirement of the machines used in greenhouse operations were measured by using a computer based data acquisition system. Energy and economical variables (i.e. output-input ratio, specific energy, production cost, net return, etc.) were calculated by using the standard equations. As a result, the operational energy and energy source requirements of the greenhouse vegetable production were found between the ranges of 23,883.5-28,034.7 and 45,763.3-49,978.8MJ/1000m{sup 2}, respectively. The energy ratio of four major greenhouse vegetables-tomato, pepper, cucumber and eggplant-was 0.32, 0.19, 0.31, 0.23, respectively. The crop yields increased as a function of the total energy inputs with the best form being second-degree polynomial. The net return of the vegetable production was found in the 595.6-2775.3$/1000m{sup 2} ranges. Among the greenhouse vegetables, tomato cultivation resulted in being the most profitable. (author)

Straw for energy production. Technology - Environment - Economy

Energy Technology Data Exchange (ETDEWEB)

Nikolaisen, L.; Nielsen, C.; Larsen, M.G.; Nielsen, V.; Zielke, U.; Kristensen, J.K.; Holm-Christensen, B.

1998-12-31

`Straw for Energy Production`, second edition, provides a readily accessible background information of special relevance to the use of straw in the Danish energy supply. Technical, environmental, and economic aspects are described in respect of boiler plants for farms, district heating plants, and combined heat and power plants (CHP). The individual sections deal with both well-known, tested technology and the most recent advances in the field of CHP production. This publication is designed with the purpose of reaching the largest possible numbers of people and so adapted that it provides a valuable aid and gives the non-professional, general reader a thorough knowledge of the subject. `Straw for Energy Production` is also available in German and Danish. (au)

Wood for energy production. Technology - environment - economy[Denmark

Energy Technology Data Exchange (ETDEWEB)

Serup, H.; Falster, H.; Gamborg, C. [and others

1999-07-01

'Wood for Energy Production', 2nd edition, is a readily understood guide to the application of wood in the Danish energy supply. The first edition was named 'Wood Chips for Energy Production'. It describes the wood fuel from forest to consumer and provides a concise introduction to technological, environmental, and financial matters concerning heating systems for farms, institutions, district heating plants, and CHP plants. The individual sections deal with both conventional, well known technology, as well as the most recent technological advances in the field of CHP production. The purpose of this publication is to reach the largest possible audiance, and it is designed so that the layman may find its background information of special relevance. 'Wood for Energy Production' is also available in German and Danish. (au)

A step by step selection method for the location and the size of a waste-to-energy facility targeting the maximum output energy and minimization of gate fee.

Science.gov (United States)

Kyriakis, Efstathios; Psomopoulos, Constantinos; Kokkotis, Panagiotis; Bourtsalas, Athanasios; Themelis, Nikolaos

2017-06-23

This study attempts the development of an algorithm in order to present a step by step selection method for the location and the size of a waste-to-energy facility targeting the maximum output energy, also considering the basic obstacle which is in many cases, the gate fee. Various parameters identified and evaluated in order to formulate the proposed decision making method in the form of an algorithm. The principle simulation input is the amount of municipal solid wastes (MSW) available for incineration and along with its net calorific value are the most important factors for the feasibility of the plant. Moreover, the research is focused both on the parameters that could increase the energy production and those that affect the R1 energy efficiency factor. Estimation of the final gate fee is achieved through the economic analysis of the entire project by investigating both expenses and revenues which are expected according to the selected site and outputs of the facility. In this point, a number of commonly revenue methods were included in the algorithm. The developed algorithm has been validated using three case studies in Greece-Athens, Thessaloniki, and Central Greece, where the cities of Larisa and Volos have been selected for the application of the proposed decision making tool. These case studies were selected based on a previous publication made by two of the authors, in which these areas where examined. Results reveal that the development of a «solid» methodological approach in selecting the site and the size of waste-to-energy (WtE) facility can be feasible. However, the maximization of the energy efficiency factor R1 requires high utilization factors while the minimization of the final gate fee requires high R1 and high metals recovery from the bottom ash as well as economic exploitation of recovered raw materials if any.

Green energy from marine algae: biogas production and composition from the anaerobic digestion of Irish seaweed species.

Science.gov (United States)

Vanegas, C H; Bartlett, J

2013-01-01

Marine algae have emerged as an alternative feedstock for the production of a number of renewable fuels, including biogas. In addition to energy potential, other characteristics make them attractive as an energy source, including their ability to absorb carbon dioxide (CO2), higher productivity rates than land-based crops and the lack of water use or land competition. For Ireland, biofuels from marine algae can play an important role by reducing imports of fossil fuels as well as providing the necessary energy in rural communities. In this study, five potential seaweed species common in Irish waters, Saccorhiza polyschides, Ulva sp., Laminaria digitata, Fucus serratus and Saccharina latissima, were co-digested individually with bovine slurry. Batch reactors of 120ml and 1000ml were set up and incubated at 35 degrees C to investigate their suitability for production of biogas. Digesters fed with S. latissima produced the maximum methane yield (335 ml g volatile solids(-1) (g(VS)(-1) followed by S. polyschides with 255 ml g(VS)(-1). L. digitata produced 246ml g(VS)(-1) and the lowest yields were from the green seaweed Ulva sp. 191ml g(VS)(-1). The methane and CO2 percentages ranged between 50-72% and 10-45%, respectively. The results demonstrated that the seaweed species investigated are good feedstocks candidates for the production of biogas and methane as a source of energy. Their use on a large-scale process will require further investigation to increase yields and reduce production costs.

Interest in energy wood and energy crop production among Finnish non-industrial private forest owners

International Nuclear Information System (INIS)

Raemoe, A.-K.; Jaervinen, E.; Latvala, T.; Toivonen, R.; Silvennoinen, H.

2009-01-01

EU targets and regulations regarding energy production and the reduction of greenhouse gas emissions have been tightening in the 2000s. In Finland the targets are planned to be achieved mainly by increasing the use of biomass. Wood already accounts for a marked proportion of Finnish energy production, but additional reserves are still available. Energy crop production also has considerable potential. Practically all Finnish farmers are also forest owners. Therefore, private forest owners are in a decisive position regarding the supply of energy wood and crops in Finland. In this paper the future supply of biomass is examined according to their past behaviour, intentions and attitudes. Finnish forest owners have a positive attitude towards the use of wood and crops in energy production. Price is becoming more critical as a motive for the supply of energy wood. Recreation and nature conservation play a smaller role than factors related to wood production and forest management as for motives for harvesting energy wood. However, almost a half of forest owners in this study were uncertain of their willingness to supply biomass. This is partly due to limited knowledge of the issues involved in energy wood and agricultural energy crop production and the underdeveloped markets for energy biomass. In order to achieve the targets, supply should be activated by further developing market practices, information, guidance and possibly other incentives for landowners. In general, there is interest among landowners in increasing the supply of energy biomass. However, the growth of supply presumes that production is an economically attractive and competitive alternative, that the markets are better organized than at present, and that more comprehensive information is available about bioenergy and biomass markets and production techniques.

Biomass in Switzerland. Energy production

International Nuclear Information System (INIS)

Guggisberg, B.

2006-01-01

In the long term, biomass could be used for energy production in a three times more intensive way, compared to current figures. A major contribution would be delivered to Switzerland's energy supply. Numerous biomass conversion technologies do exist, for the production of heat, power or vehicle fuel. However, the implementation of such a large-scale utilisation of biomass requires a couple of strategic decisions in order to improve the framework conditions for biomass development and precisely target the supporting measures applicable to both research and pilot plants. In short, a clear and efficient strategy is necessary in what regards biomass, that will be used for the definition of a future catalogue of measures. (author)

Causal nexus between energy consumption and carbon dioxide emission for Malaysia using maximum entropy bootstrap approach.

Science.gov (United States)

Gul, Sehrish; Zou, Xiang; Hassan, Che Hashim; Azam, Muhammad; Zaman, Khalid

2015-12-01

This study investigates the relationship between energy consumption and carbon dioxide emission in the causal framework, as the direction of causality remains has a significant policy implication for developed and developing countries. The study employed maximum entropy bootstrap (Meboot) approach to examine the causal nexus between energy consumption and carbon dioxide emission using bivariate as well as multivariate framework for Malaysia, over a period of 1975-2013. This is a unified approach without requiring the use of conventional techniques based on asymptotical theory such as testing for possible unit root and cointegration. In addition, it can be applied in the presence of non-stationary of any type including structural breaks without any type of data transformation to achieve stationary. Thus, it provides more reliable and robust inferences which are insensitive to time span as well as lag length used. The empirical results show that there is a unidirectional causality running from energy consumption to carbon emission both in the bivariate model and multivariate framework, while controlling for broad money supply and population density. The results indicate that Malaysia is an energy-dependent country and hence energy is stimulus to carbon emissions.

Production of sustainable methane from renewable energy and captured carbon dioxide with the use of Solid Oxide Electrolyzer: A thermodynamic assessment

International Nuclear Information System (INIS)

Stempien, Jan Pawel; Ni, Meng; Sun, Qiang; Chan, Siew Hwa

2015-01-01

A possible pathway for renewable and sustainable methane production from captured carbon dioxide, water (or seawater) and renewable electricity is proposed and analysed. The proposed system includes Solid Oxide Electrolyzer Cell combined with ex-situ methane synthesis reactor comprising Sabatier, Methanation and Water-Gas Shift reactions. A well validated electrochemical model is used to describe the behaviour of the electrolyzer for steam/carbon dioxide co-electrolysis. The methane synthesis reactor is modelled by a set of equations based on thermodynamic equilibrium reaction constants. Effects of current density, temperature, pressure and initial steam to carbon dioxide ratio on system performance are analysed and their effects are discussed. It is found that a simple, single-pass system without heat recuperation could achieve a maximum overall energy efficiency of 60.87% (based on lower heating value), a maximum electrical energy efficiency of 81.08% (based on lower heating value), and a maximum amount of methane production of ∼1.52 Nm 3  h −1  m −2 of electrolyzer. It is also found that conversion of ∼100% captured carbon dioxide is possible in the proposed system. - Highlights: • Analysis of Solid Oxide Electrolyzer combined with methane synthesis process. • Efficiency of converting water and carbon dioxide into synthetic, renewable methane above 81%. • Effects of process temperature, pressure, gas flux and compositions were analysed. • Methane production of ∼1.52 [Nm 3 h −1 m −2 of electrolyzer]. • Conversion of ∼100% of captured CO 2 is possible

Hydrogen Production Using Nuclear Energy

Energy Technology Data Exchange (ETDEWEB)

Verfondern, K. [Research Centre Juelich (Germany)

2013-03-15

world. In recent years, the scope of the IAEA's programme has been widened to include other more promising applications such as nuclear hydrogen production and higher temperature process heat applications. The OECD Nuclear Energy Agency, Euratom and the Generation IV International Forum have also shown interest in the non-electric applications of nuclear power based on future generation advanced and innovative nuclear reactors. This report was developed under an IAEA project with the objective of providing updated, balanced and objective information on the current status of hydrogen production processes using nuclear energy. It documents the state of the art of the development of hydrogen as an energy carrier in many Member States, as well as its corresponding production through the use of nuclear power. The report includes an introduction to the technology of nuclear process heat reactors as a means of producing hydrogen or other upgraded fuels, with a focus on high temperature reactor technology to achieve simultaneous generation of electricity and high temperature process heat and steam. Special emphasis is placed on the safety aspects of nuclear hydrogen production systems.

Innovations in greenhouse systems - Energy conservation by system design, sensors and decision support systems

NARCIS (Netherlands)

Hemming, S.; Balendonck, J.; Dieleman, J.A.; Gelder, De A.; Kempkes, F.L.K.; Swinkels, G.L.A.M.; Visser, De P.H.B.; Zwart, De H.F.

2017-01-01

The targets for energy saving in Dutch horticulture are high. Research follows the two lines: total energy reduction and sustainability. The principles for that are: maximum use of natural sunlight (free energy input to greenhouse, free light for crop growth and production); maximum insulation

Dossier: renewable energies for heat production; Dossier: energies renouvelables pour la production de chaleur

Energy Technology Data Exchange (ETDEWEB)

Anon.

2002-09-01

This dossier makes a state-of-the-art of today's applications of renewable energy sources in the residential, collective and tertiary sectors for the space heating and the hot water production. In France, three energy sources profit by a particularly favorable evolution: the solar thermal, the wood fuel and the geothermal energies. In these sectors, the offer of reliable and technically achieved appliances has been considerably widen thanks to the impulse of some French and German manufacturers. Part 1 - solar thermal: individual solar water heaters (monobloc, thermosyphon with separate tank, forced circulation systems, auxiliary heating systems); combined solar systems (direct heating floor, system with storage); collective solar systems for hot water production (receivers, efficiency, heat storage and transfer, auxiliary heating, decentralized systems); heating of open-air swimming pools; some attempts in air-conditioning; the warranty of results. Part 2 - wood fuels: domestic space heating (log boilers, installation rules, hydro-accumulation, automatic boilers); collective and tertiary wood-fueled heating plants (design of boiler plants, fuel supply, combustion chamber, smoke purification systems, ash removal, regulation system), fuels for automatic collective plants, design and installation rules. Part 3 - geothermal energy: different types (water-source and ground-source heat pumps, financial incentive). (J.S.)

Market distortions and aggregate productivity: Evidence from Chinese energy enterprises

International Nuclear Information System (INIS)

Dai, Xiaoyong; Cheng, Liwei

2016-01-01

Market distortions can generate resource misallocations across heterogeneous firms and reduce aggregate productivity. This paper measures market distortions and aggregate productivity growth in China's energy sector. We use the wedge between output elasticities and factor shares in revenues to recover a measure of firm-level market distortions. Using data on a large sample of Chinese energy enterprises from 1999 to 2007, our estimations provide strong evidence of the existence of both factor and product market distortions within and across China's various energy industries. The productivity aggregation and decomposition results demonstrate that the estimated aggregate productivity growth (APG) is, on average, 2.595% points per year, of which technological change, resource reallocation, and firm entries and exits account for 1.981, 0.068, and 0.546% points, respectively. The weak contributions of resource reallocation and firm turnover to APG are also found in energy sub-industries, except in the coal industry. Our research suggests that China's energy sector has major potential for productivity gains from resource reallocation through the reduction of market distortions. - Highlights: •We estimate market distortions and productivity growth of China's energy sector. •We use a large sample of Chinese energy enterprises. •There are evidences of the existence of factor and product market distortions. •Aggregate productivity growth is largely driven by firm-level technological change. •China's energy sector can realize productivity gains from resource reallocations.

Maximum power point tracking techniques for wind energy systems using three levels boost converter

Science.gov (United States)

Tran, Cuong Hung; Nollet, Frédéric; Essounbouli, Najib; Hamzaoui, Abdelaziz

2018-05-01

This paper presents modeling and simulation of three level Boost DC-DC converter in Wind Energy Conversion System (WECS). Three-level Boost converter has significant advantage compared to conventional Boost. A maximum power point tracking (MPPT) method for a variable speed wind turbine using permanent magnet synchronous generator (PMSG) is also presented. Simulation of three-level Boost converter topology with Perturb and Observe algorithm and Fuzzy Logic Control is implemented in MATLAB/SIMULINK. Results of this simulation show that the system with MPPT using fuzzy logic controller has better performance to the Perturb and Observe algorithm: fast response under changing conditions and small oscillation.

Hydrogen production from solar energy

Science.gov (United States)

Eisenstadt, M. M.; Cox, K. E.

1975-01-01

Three alternatives for hydrogen production from solar energy have been analyzed on both efficiency and economic grounds. The analysis shows that the alternative using solar energy followed by thermochemical decomposition of water to produce hydrogen is the optimum one. The other schemes considered were the direct conversion of solar energy to electricity by silicon cells and water electrolysis, and the use of solar energy to power a vapor cycle followed by electrical generation and electrolysis. The capital cost of hydrogen via the thermochemical alternative was estimated at $575/kW of hydrogen output or $3.15/million Btu. Although this cost appears high when compared with hydrogen from other primary energy sources or from fossil fuel, environmental and social costs which favor solar energy may prove this scheme feasible in the future.

Unbinned maximum likelihood fit for the CP conserving couplings for W + photon production at CDF

International Nuclear Information System (INIS)

Lannon, K.

1994-01-01

We present an unbinned maximum likelihood fit as an alternative to the currently used fit for the CP conserving couplings W plus photon production studied at CDF. We show that a four parameter double exponential fits the E T spectrum of the photon very well. We also show that the fit parameters can be related to and by a second order polynomial. Finally, we discuss various conclusions we have reasoned from our results to the fit so far

Energy use pattern and optimization of energy required for broiler production using data envelopment analysis

Directory of Open Access Journals (Sweden)

Sama Amid

2016-06-01

Full Text Available A literature review shows that energy consumption in agricultural production in Iran is not efficient and a high degree of inefficiency in broiler production exists in Iran. Energy consumption of broiler production in Ardabil province of Iran was studied and the non-parametric method of data envelopment analysis (DEA was used to analyze energy efficiency, separate efficient from inefficient broiler producers, and calculate wasteful use of energy to optimize energy. Data was collected using face-to-face questionnaires from 70 broiler farmers in the study area. Constant returns to scale (CCR and variable returns to scale (BCC models of DEA were applied to assess the technical efficiency of broiler production. The results indicated that total energy use was 154,283 MJ (1000 bird−1 and the share of fuel at 61.4% was the highest of all inputs. The indices of energy efficiency, energy productivity, specific energy, and net energy were found to be 0.18, 0.02 kg MJ−1, 59.56 MJ kg−1, and −126,836 MJ (1000 bird−1, respectively. The DEA results revealed that 40% and 22.86% of total units were efficient based on the CCR and BCC models, respectively. The average technical, pure technical, and scale efficiency of broiler farmers was 0.88, 0.93, and 0.95, respectively. The results showed that 14.53% of total energy use could be saved by converting the present units to optimal conditions. The contribution of fuel input to total energy savings was 72% and was the largest share, followed by feed and electricity energy inputs. The results of this study indicate that there is good potential for increasing energy efficiency of broiler production in Iran by following the recommendations for efficient energy use.

Hydrogen Production Costs of Various Primary Energy Sources

International Nuclear Information System (INIS)

Choi, Jae Hyuk; Tak, Nam Il; Kim, Yong Hee; Park, Won Seok

2005-11-01

Many studies on the economical aspects of hydrogen energy technologies have been conducted with the increase of the technical and socioeconomic importance of the hydrogen energy. However, there is still no research which evaluates the economy of hydrogen production from the primary energy sources in consideration of Korean situations. In this study, the hydrogen production costs of major primary energy sources are compared in consideration of the Korean situations such as feedstock price, electricity rate, and load factor. The evaluation methodology is based on the report of the National Academy of Science (NAS) of U.S. The present study focuses on the possible future technology scenario defined by NAS. The scenario assumes technological improvement that may be achieved if present research and development (R and D) programs are successful. The production costs by the coal and natural gas are 1.1 $/kgH 2 and 1.36 $/kgH 2 , respectively. However, the fossil fuels are susceptible to the price variation depending on the oil and the raw material prices, and the hydrogen production cost also depends on the carbon tax. The economic competitiveness of the renewable energy sources such as the wind, solar, and biomass are relatively low when compared with that of the other energy sources. The estimated hydrogen production costs from the renewable energy sources range from 2.35 $/kgH 2 to 6.03 $/kgH 2 . On the other hand, the production cost by nuclear energy is lower than that of natural gas or coal when the prices of the oil and soft coal are above $50/barrel and 138 $/ton, respectively. Taking into consideration the recent rapid increase of the oil and soft coal prices and the limited fossil resource, the nuclear-hydrogen option appears to be the most economical way in the future

Biomass production for direct generation of energy

International Nuclear Information System (INIS)

1992-01-01

In continuing its activities for the formation of public opinion the Deutsche Farming Association) held a colloquium in 1991 on the issue of biomass production and combustion. Its aim was to gather all current knowledge on this issue and, for the first time, to make a comprehensive appraisal of it. The following aspects were dealt with: Abatement of atmospheric pollution, ecologically oriented production, nature conservation, organisation of decentralized power plant operating corporations, state of the art in combustion technology, operational calculations and, not least, agrarin-political framework conditions. The meeting yielded important statements on remarkable innovations in the area of ecological biomass production and for its utilization as an energy source together with the conventional energy sources of oil, gas, coal and nuclear energy. (orig.) [de

Environmental costs of fossil fuel energy production

International Nuclear Information System (INIS)

Riva, A.; Trebeschi, C.

1997-01-01

The costs of environmental impacts caused by fossil fuel energy production are external to the energy economy and normally they are not reflected in energy prices. To determine the environmental costs associated with an energy source a detailed analysis of all environmental impacts of the complete energy cycle is required. The economic evaluation of environmental damages is presented caused by atmospheric emissions produced by fossil fuel combustion for different uses. Considering the emission factors of sulphur oxides, nitrogen oxides, dust and carbon dioxide and the economic evaluation of their environmental damages reported in literature, a range of environmental costs associated with different fossil fuels and technologies is presented. A comparison of environmental costs resulting from atmospheric emissions produced by fossil-fuel combustion for energy production shows that natural gas has a significantly higher environmental value than other fossil fuels. (R.P.)

A novel minimum cost maximum power algorithm for future smart home energy management

Directory of Open Access Journals (Sweden)

A. Singaravelan

2017-11-01

Full Text Available With the latest development of smart grid technology, the energy management system can be efficiently implemented at consumer premises. In this paper, an energy management system with wireless communication and smart meter are designed for scheduling the electric home appliances efficiently with an aim of reducing the cost and peak demand. For an efficient scheduling scheme, the appliances are classified into two types: uninterruptible and interruptible appliances. The problem formulation was constructed based on the practical constraints that make the proposed algorithm cope up with the real-time situation. The formulated problem was identified as Mixed Integer Linear Programming (MILP problem, so this problem was solved by a step-wise approach. This paper proposes a novel Minimum Cost Maximum Power (MCMP algorithm to solve the formulated problem. The proposed algorithm was simulated with input data available in the existing method. For validating the proposed MCMP algorithm, results were compared with the existing method. The compared results prove that the proposed algorithm efficiently reduces the consumer electricity consumption cost and peak demand to optimum level with 100% task completion without sacrificing the consumer comfort.

Energy conservation opportunities: audit vis-a-vis mine productivity

Energy Technology Data Exchange (ETDEWEB)

Iyer, G.H.

2009-07-01

Mining operation, whether opencast or underground, with modern equipment is highly energy intensive, needing energy conservation and management to ensure efficiency, cost effectiveness, and overall productivity. Exhaustible primary energy resources such as coal, lignite, oil, and nuclear fuels are being mined out to meet our energy needs. An attempt has been made in this paper to highlight the energy conservation opportunities, energy audit, the relevant Energy Conservation Act 2001 and certain energy saving measures leading to higher productivity followed by a few case study examples. 3 refs.

Ergodicity, Maximum Entropy Production, and Steepest Entropy Ascent in the Proofs of Onsager's Reciprocal Relations

Science.gov (United States)

Benfenati, Francesco; Beretta, Gian Paolo

2018-04-01

We show that to prove the Onsager relations using the microscopic time reversibility one necessarily has to make an ergodic hypothesis, or a hypothesis closely linked to that. This is true in all the proofs of the Onsager relations in the literature: from the original proof by Onsager, to more advanced proofs in the context of linear response theory and the theory of Markov processes, to the proof in the context of the kinetic theory of gases. The only three proofs that do not require any kind of ergodic hypothesis are based on additional hypotheses on the macroscopic evolution: Ziegler's maximum entropy production principle (MEPP), the principle of time reversal invariance of the entropy production, or the steepest entropy ascent principle (SEAP).

ENERGY STAR Certified Products - Lighting

Data.gov (United States)

U.S. Environmental Protection Agency — This data set contains a simplified list of all currently certified ENERGY STAR Lighting models with basic model information collected across all product categories...

Improving energy productivity of sunflower production using data envelopment analysis (DEA) approach.

Science.gov (United States)

Avval, Seyed Hashem Mousavi; Rafiee, Shahin; Jafari, Ali; Mohammadi, Ali

2011-08-15

Efficient use of energy in agriculture is one of the conditions for sustainable agricultural production. This study applies the data envelopment analysis (DEA) approach to the data of 95 randomly selected farms to investigate the technical and scale efficiencies of farmers with respect to energy use for sunflower production in Golestan province, Iran. The study also helps to identify the wasteful usage and the optimum level of energy from different inputs. According to the results of DEA models, about 36% of farmers were found to be technically efficient and the mean efficiency of sunflower producers was found to be 0.87 and 0.96 under the constant and variable returns to scale assumptions respectively. The optimum energy requirement was calculated as 8448.3 MJ ha⁻¹; accordingly, a potential reduction of 10.8% (1020.3 MJ ha⁻¹) in total energy input could be achieved by raising the performance of farmers to the highest level. Applying a better machinery management technique and conservation tillage methods, application of fertilisers by performance monitoring and utilisation of alternative sources of energy such as compost and chopped residues may be the pathways for improving energy productivity and reducing the environmental footprint. Copyright © 2011 Society of Chemical Industry.

Technology selection for hydrogen production using nuclear energy

International Nuclear Information System (INIS)

Siti Alimah; Erlan Dewita

2008-01-01

The NPP can either be used to produce electricity, or as heat source for non-electric applications (cogeneration). High Temperature Reactor (HTR) with high outlet coolant temperature around 900~1000 o C, is a reactor type potential for cogeneration purposes such as hydrogen production and other chemical industry processes that need high heat. Considering the national energy policy that a balanced arrangement of renewable and unrenewable natural resources has to be made to keep environmental conservation for the sake of society prosperity in the future, hydrogen gas production using nuclear heat is an appropriate choice. Hydrogen gas is a new energy which is environmentally friendly that it is a prospecting alternative energy source in the future. Within the study, a comparison of three processes of hydrogen gas production covering electrolysis, steam reforming and sulfur-iodine cycle, have been conducted. The parameters that considered are the production cost, capital cost and energy cost, technological status, the independence of fossil fuel, the environmental friendly aspect, as well as the efficiency and the independence of corrosion-resistance material. The study result showed that hydrogen gas production by steam reforming is a better process compared to electrolysis and sulfur-iodine process. Therefore, steam reforming process can be a good choice for hydrogen gas production using nuclear energy in Indonesia. (author)

Productivity and Energy Expenditure by Sawyers When Using ...

African Journals Online (AJOL)

Therefore, based on overall results it is concluded that, the PLSP is technically more appropriate technology or method for reducing energy expenditure and for increasing productivity during timber harvesting in agroforestry farms. Keywords: Productivity, Energy expenditure, Pitsawing and Portable log sawing. Rwanda ...

Information Entropy Production of Maximum Entropy Markov Chains from Spike Trains

Science.gov (United States)

Cofré, Rodrigo; Maldonado, Cesar

2018-01-01

We consider the maximum entropy Markov chain inference approach to characterize the collective statistics of neuronal spike trains, focusing on the statistical properties of the inferred model. We review large deviations techniques useful in this context to describe properties of accuracy and convergence in terms of sampling size. We use these results to study the statistical fluctuation of correlations, distinguishability and irreversibility of maximum entropy Markov chains. We illustrate these applications using simple examples where the large deviation rate function is explicitly obtained for maximum entropy models of relevance in this field.

Energy, exergy and sustainability analyses of hybrid renewable energy based hydrogen and electricity production and storage systems: Modeling and case study

International Nuclear Information System (INIS)

Caliskan, Hakan; Dincer, Ibrahim; Hepbasli, Arif

2013-01-01

In this study, hybrid renewable energy based hydrogen and electricity production and storage systems are conceptually modeled and analyzed in detail through energy, exergy and sustainability approaches. Several subsystems, namely hybrid geothermal energy-wind turbine-solar photovoltaic (PV) panel, inverter, electrolyzer, hydrogen storage system, Proton Exchange Membrane Fuel Cell (PEMFC), battery and loading system are considered. Also, a case study, based on hybrid wind–solar renewable energy system, is conducted and its results are presented. In addition, the dead state temperatures are considered as 0 °C, 10 °C, 20 °C and 30 °C, while the environment temperature is 30 °C. The maximum efficiencies of the wind turbine, solar PV panel, electrolyzer, PEMFC are calculated as 26.15%, 9.06%, 53.55%, and 33.06% through energy analysis, and 71.70%, 9.74%, 53.60%, and 33.02% through exergy analysis, respectively. Also, the overall exergy efficiency, ranging from 5.838% to 5.865%, is directly proportional to the dead state temperature and becomes higher than the corresponding energy efficiency of 3.44% for the entire system. -- Highlights: ► Developing a three-hybrid renewable energy (geothermal–wind–solar)-based system. ► Undertaking a parametric study at various dead state temperatures. ► Investigating the effect of dead state temperatures on exergy efficiency

Nuclear energy contribution to restraining greenhouse gas emissions and long-term energy production

International Nuclear Information System (INIS)

Khoda-Bakhsh, R.

2004-01-01

An important source of greenhouse gases, in particular Co 2 , is fossil fuel combustion for energy applications. Since nuclear power is an energy source that does not produce Co 2 , nuclear energy is already making a contribution to restraining greenhouse gas emissions. Because it has been internationally decided to reduce carbon dioxide emission before the year 2005 in order to avoid the green house catastrophy of the earth's atmosphere, and since there is an urgent need of energy especially in the developing countries, there is now a strong demand for alternative energy sources. While the established low cost energy production by light water nuclear fission reactors could be a solution for a period of transition (limited by resources of the light Uranium isotope), fusion energy is of interest for long- term and large scale energy production to provide the increased energy demand

Exploring high-density baryonic matter: Maximum freeze-out density

Energy Technology Data Exchange (ETDEWEB)

Randrup, Joergen [Lawrence Berkeley National Laboratory, Nuclear Science Division, Berkeley, CA (United States); Cleymans, Jean [University of Cape Town, UCT-CERN Research Centre and Department of Physics, Rondebosch (South Africa)

2016-08-15

The hadronic freeze-out line is calculated in terms of the net baryon density and the energy density instead of the usual T and μ{sub B}. This analysis makes it apparent that the freeze-out density exhibits a maximum as the collision energy is varied. This maximum freeze-out density has μ{sub B} = 400 - 500 MeV, which is above the critical value, and it is reached for a fixed-target bombarding energy of 20-30 GeV/N well within the parameters of the proposed NICA collider facility. (orig.)

ENERGY USE IN APPLE PRODUCTION IN THE ESFAHAN ...

African Journals Online (AJOL)

journal

Apple production needs to improve the efficiency of energy consumption and to employ renewable energy. ... derived from Neyman method (Ozkan et al.,. 2004). .... management might reduce the indirect energy .... Handbook of Energy.

Energy productivity and Chinese local officials’ promotions: Evidence from provincial governors

International Nuclear Information System (INIS)

Chen, Xiude; Qin, Quande; Wei, Y.-M.

2016-01-01

Improving energy productivity is one of the most cost-effective ways to achieve a sustainable development target. The existing literature has shown some factors that have driven the improvement in China’s energy productivity. However, these studies do little to tackle the role of Chinese local officials. Political promotions can be seen as the most important career incentive for Chinese local officials. Hence, we intend to study whether energy productivity affects Chinese local officials’ promotions in this paper. The data of position changes for the 31 provincial governors during 1978‐2012 are utilized. We adopted probit models to empirically examine the correlation between provincial governors’ political promotions and energy productivity. The empirical results demonstrate that (1) energy productivity has a significantly positive impact on provincial governors’ political promotions in China, meaning that the provincial governors have the momentum to improve energy productivity; and (2) the effect of energy productivity on provincial governors’ political promotions has evolved, dynamically changing along with the transformation of the economic growth mode and the adjustment of the local officials’ promotion mechanism. The results are helpful in understanding the drivers of the improvement in China’s energy productivity and provide insightful implications for conducting energy policy in China. - Highlights: •The data of position changes for China’s provincial governors during 1978–2012 are utilized. •Energy productivity has a positive impact on provincial governors’ promotion in China. •Political incentive is an important driver of the improvement in China’s energy productivity. •The correlation between energy productivity and local officials’ promotions was evolved.

Biomass energy production in agriculture: A weighted goal programming analysis

International Nuclear Information System (INIS)

Ballarin, A.; Vecchiato, D.; Tempesta, T.; Marangon, F.; Troiano, S.

2011-01-01

Energy production from biomasses can be an important resource that, when combined with other green energies such as wind power and solar plants, can contribute to reduce dependency on fossil fuels. The aim of this study is to assess how agriculture could contribute to the production of bio-energy. A multi-period Weighted Goal Programming model (MpWGP) has been applied to identify the optimal land use combinations that simultaneously maximise farmers' income and biomass energy production under three concurrent constraints: water, labour and soil availability. Alternative scenarios are considered that take into account the effect of climate change and social change. The MpWGP model was tested with data from the Rovigo county area (Italy) over a 15-year time period. Our findings show that trade-off exists between the two optimisation targets considered. Although the optimisation of the first target requires traditional agricultural crops, which are characterised by high revenue and a low production of biomass energy, the latter would be achievable with intensive wood production, namely, high-energy production and low income. Our results also show the importance of the constraints imposed, particularly water availability; water scarcity has an overall negative effect and specifically affects the level of energy production. - Research Highlights: → The aim of this study is to assess how agriculture could contribute to the production of bio-energy. → A multi-period (15-year) Weighted Goal Programming model (MpWGP) has been applied. → We identify the optimal land use combinations that simultaneously maximise farmers' income and biomass energy production. → Three concurrent constraints have been considered: water, labour and soil availability.→ Water scarcity has an overall negative effect and specifically affects the level of energy production.

A maximum power point tracking for photovoltaic-SPE system using a maximum current controller

Energy Technology Data Exchange (ETDEWEB)

Muhida, Riza [Osaka Univ., Dept. of Physical Science, Toyonaka, Osaka (Japan); Osaka Univ., Dept. of Electrical Engineering, Suita, Osaka (Japan); Park, Minwon; Dakkak, Mohammed; Matsuura, Kenji [Osaka Univ., Dept. of Electrical Engineering, Suita, Osaka (Japan); Tsuyoshi, Akira; Michira, Masakazu [Kobe City College of Technology, Nishi-ku, Kobe (Japan)

2003-02-01

Processes to produce hydrogen from solar photovoltaic (PV)-powered water electrolysis using solid polymer electrolysis (SPE) are reported. An alternative control of maximum power point tracking (MPPT) in the PV-SPE system based on the maximum current searching methods has been designed and implemented. Based on the characteristics of voltage-current and theoretical analysis of SPE, it can be shown that the tracking of the maximum current output of DC-DC converter in SPE side will track the MPPT of photovoltaic panel simultaneously. This method uses a proportional integrator controller to control the duty factor of DC-DC converter with pulse-width modulator (PWM). The MPPT performance and hydrogen production performance of this method have been evaluated and discussed based on the results of the experiment. (Author)

Risk of energy production

International Nuclear Information System (INIS)

Inhaber, Herbert.

1978-03-01

Every human activity involves risk of accident or disease. Generation of energy is no exception. Although such risk has been considered for conventional systems (coal, oil and nuclear), a similar analysis for the so-called alternative or non-conventional systems (solar, wind, ocean thermal and methanol) has been lacking. This paper presents an evaluation of the risk, both occupational and to the public, of non-conventional energy systems. They are considered both in absolute terms and in relation to conventional systems. The risk of most non-conventional systems, per unit of energy output, is comparable to, and in some cases much higher than, the risk from coal and oil. This conclusion holds whether we consider deaths or injuries. Nuclear power and natural gas had the lowest overall risk of the ten technologies considered. Ocean thermal energy ranked third. The surprising result is that the other seven technologies considered were found to be up to 100 times less safe. The total risk is calculated by considering six components: material acquisition and construction, emissions caused by material production, operation and maintenance, energy back-up, energy storage, and transportation. In this way the risk of widely different systems can be fairly assessed. This methodology of 'risk accounting' will not tell us which energy technology to use. However, it can be employed to inform society of the risk inherent in competing energy systems. (author)

Energy analysis of solar photovoltaic module production in India

International Nuclear Information System (INIS)

Prakash, R.; Bansal, N.K.

1995-01-01

The objective of this article is to evaluate the energy consumption in solar photovoltaic (SPV) module production in India and examine its implications for large-scale introduction of SPV plants in the country. Data on energy used in SPV production were collected from existing manufacturing facilities in the country. The energy payback period turns out to be approximately 4 years. This is comparable to energy payback periods of similar modules produced internationally. However, if an ambitious program of introducing SPV power production is undertaken to contribute substantially to the power scenario in the country, an annual growth rate beyond 21% will render the program an energy sink rather than an energy source, as borne out by dynamic energy analysis. Policy implications are also discussed in light of this analysis

High-Efficiency Food Production in a Renewable Energy Based Micro-Grid

Science.gov (United States)

Bubenheim, David L.

2017-01-01

Controlled Environment Agriculture (CEA) systems can be used to produce high-quality, desirable food year round, and the fresh produce can positively contribute to the health and well being of residents in communities with difficult supply logistics. While CEA has many positive outcomes for a remote community, the associated high electric demands have prohibited widespread implementation in what is typically already a fully subscribed power generation and distribution system. Recent advances in CEA technologies as well as renewable power generation, storage, and micro-grid management are increasing system efficiency and expanding the possibilities for enhancing community supporting infrastructure without increasing demands for outside supplied fuels. We will present examples of how new lighting, nutrient delivery, and energy management and control systems can enable significant increases in food production efficiency while maintaining high yields in CEA.Examples from Alaskan communities where initial incorporation of renewable power generation, energy storage and grid management techniques have already reduced diesel fuel consumption for electric generation by more than 40 and expanded grid capacity will be presented. We will discuss how renewable power generation, efficient grid management to extract maximum community service per kW, and novel energy storage approaches can expand the food production, water supply, waste treatment, sanitation and other community support services without traditional increases of consumable fuels supplied from outside the community. These capabilities offer communities with a range of choices to enhance their communities. The examples represent a synergy of technology advancement efforts to develop sustainable community support systems for future space-based human habitats and practical implementation of infrastructure components to increase efficiency and enhance health and well-being in remote communities today and tomorrow.

Energy use in the food-products (not elsewhere classified) industry

Energy Technology Data Exchange (ETDEWEB)

Cleland, A.C.; Earle, M.D.

1980-06-01

Energy consumption data in the food products industry were collected by a postal survey and by factory energy surveys. Average levels of energy consumption were evaluated for various product types, sugar refining was found to require 4.0 MJ/kg, fat and oil processing 8.5 MJ/kg, pasta product manufacture 4.3 MJ/kg, instant coffee production 48 MJ/kg, roasting of coffee beans 2.2 MJ/kg, vinegar production 3.3 MJ/litre, compressed yeast production 5.4 MJ/kg, sandwich spread preparation 5.3 MJ/kg, drying of products with initial moisture contents below 30% 8.2 MJ/kg, drying of products with initial moisture contents of 70 to 90% 39 MJ/kg and dry mixing of powders 0.46 MJ/kg. Data were also obtained for a variety of other minor products. For any particular product, differences in energy use that occurred between factories could largely be explained by differences in types of factory services and processes. Some data were available for equivalent US industries and in general, the New Zealand industy uses either a similar amount of or less energy than these United States industries. Possible areas for energy conservation in the industry are discussed.

Energy-Based Evaluations on Eucalyptus Biomass Production

Directory of Open Access Journals (Sweden)

Thiago L. Romanelli

2012-01-01

Full Text Available Dependence on finite resources brings economic, social, and environmental concerns. Planted forests are a biomass alternative to the exploitation of natural forests. In the exploitation of the planted forests, planning and management are key to achieve success, so in forestry operations, both economic and noneconomic factors must be considered. This study aimed to compare eucalyptus biomass production through energy embodiment of anthropogenic inputs and resource embodiment including environmental contribution (emergy for the commercial forest in the Sao Paulo, Brazil. Energy analyses and emergy synthesis were accomplished for the eucalyptus production cycles. It was determined that emergy synthesis of eucalyptus production and sensibility analysis for three scenarios to adjust soil acidity (lime, ash, and sludge. For both, energy analysis and emergy synthesis, harvesting presented the highest input demand. Results show the differences between energy analysis and emergy synthesis are in the conceptual underpinnings and accounting procedures. Both evaluations present similar trends and differ in the magnitude of the participation of an input due to its origin. For instance, inputs extracted from ores, which represent environmental contribution, are more relevant for emergy synthesis. On the other hand, inputs from industrial processes are more important for energy analysis.

Fusion Energy for Hydrogen Production

Energy Technology Data Exchange (ETDEWEB)

Fillo, J. A.; Powell, J. R.; Steinberg, M.; Salzano, F.; Benenati, R.; Dang, V.; Fogelson, S.; Isaacs, H.; Kouts, H.; Kushner, M.; Lazareth, O.; Majeski, S.; Makowitz, H.; Sheehan, T. V.

1978-09-01

The decreasing availability of fossil fuels emphasizes the need to develop systems which will produce synthetic fuel to substitute for and supplement the natural supply. An important first step in the synthesis of liquid and gaseous fuels is the production of hydrogen. Thermonuclear fusion offers an inexhaustible source of energy for the production of hydrogen from water. Depending on design, electric generation efficiencies of approximately 40 to 60% and hydrogen production efficiencies by high temperature electrolysis of approximately 50 to 70% are projected for fusion reactors using high temperature blankets.

Rate maximum calculation of Dpa in CNA-II pressure vessel

International Nuclear Information System (INIS)

Mascitti, J. A

2012-01-01

The maximum dpa rate was calculated for the reactor in the following state: fresh fuel, no Xenon, a Boron concentration of 15.3 ppm, critical state, its control rods in the criticality position, hot, at full power (2160 MW). It was determined that the maximum dpa rate under such conditions is 3.54(2)x10 12 s -1 and it is located in the positions corresponding to θ=210 o in the azimuthal direction, and z=20 cm and -60 cm respectively in the axial direction, considering the calculation mesh centered at half height of the fuel element (FE) active length. The dpa rate spectrum was determined as well as the contribution to it for 4 energy groups: a thermal group, two epithermal groups and a fast one. The maximum dpa rate considering the photo-neutrons production from (γ, n) reaction in the heavy water of coolant and moderator was 3.93(4)x10 12 s -1 that is 11% greater than the obtained without photo-neutrons. This verified significant difference between both cases, suggest that photo-neutrons in large heavy water reactors such as CNA-II should not be ignored. The maximum DPA rate in the first mm of the reactor pressure vessel was calculated too and it was obtained a value of 4.22(6)x10 12 s -1 . It should be added that the calculation was carried out with the reactor complete accurate model, with no approximations in spatial or energy variables. Each value has, between parentheses, a percentage relative error representing the statistical uncertainty due to the probabilistic Monte Carlo method used to estimate it. More representative values may be obtained with this method if equilibrium burn-up distribution is used (author)

WIND ENERGY CONVERSION SYSTEMS - A TECHNICAL REVIEW

Directory of Open Access Journals (Sweden)

N. RAMESH BABU

2013-08-01

Full Text Available Wind power production has been under the main focus for the past decade in power production and tremendous amount of research work is going on renewable energy, specifically on wind power extraction. Wind power provides an eco-friendly power generation and helps to meet the national energy demand when there is a diminishing trend in terms of non-renewable resources. This paper reviews the modeling of Wind Energy Conversion Systems (WECS, control strategies of controllers and various Maximum Power Point Tracking (MPPT technologies that are being proposed for efficient production of wind energy from the available resource.

Non-equilibrium thermodynamics, maximum entropy production and Earth-system evolution.

Science.gov (United States)

Kleidon, Axel

2010-01-13

The present-day atmosphere is in a unique state far from thermodynamic equilibrium. This uniqueness is for instance reflected in the high concentration of molecular oxygen and the low relative humidity in the atmosphere. Given that the concentration of atmospheric oxygen has likely increased throughout Earth-system history, we can ask whether this trend can be generalized to a trend of Earth-system evolution that is directed away from thermodynamic equilibrium, why we would expect such a trend to take place and what it would imply for Earth-system evolution as a whole. The justification for such a trend could be found in the proposed general principle of maximum entropy production (MEP), which states that non-equilibrium thermodynamic systems maintain steady states at which entropy production is maximized. Here, I justify and demonstrate this application of MEP to the Earth at the planetary scale. I first describe the non-equilibrium thermodynamic nature of Earth-system processes and distinguish processes that drive the system's state away from equilibrium from those that are directed towards equilibrium. I formulate the interactions among these processes from a thermodynamic perspective and then connect them to a holistic view of the planetary thermodynamic state of the Earth system. In conclusion, non-equilibrium thermodynamics and MEP have the potential to provide a simple and holistic theory of Earth-system functioning. This theory can be used to derive overall evolutionary trends of the Earth's past, identify the role that life plays in driving thermodynamic states far from equilibrium, identify habitability in other planetary environments and evaluate human impacts on Earth-system functioning. This journal is © 2010 The Royal Society

The Peak of the Oil Age - Analyzing the world oil production Reference Scenario in World Energy Outlook 2008

International Nuclear Information System (INIS)

Aleklett, Kjell; Hoeoek, Mikael; Jakobsson, Kristofer; Lardelli, Michael; Snowden, Simon; Soederbergh, Bengt

2010-01-01

The assessment of future global oil production presented in the IEA's World Energy Outlook 2008 (WEO 2008) is divided into 6 fractions; four relate to crude oil, one to non-conventional oil, and the final fraction is natural-gas-liquids (NGL). Using the production parameter, depletion-rate-of-recoverable-resources, we have analyzed the four crude oil fractions and found that the 75 Mb/d of crude oil production forecast for year 2030 appears significantly overstated, and is more likely to be in the region of 55 Mb/d. Moreover, analysis of the other fractions strongly suggests lower than expected production levels. In total, our analysis points to a world oil supply in 2030 of 75 Mb/d, some 26 Mb/d lower than the IEA predicts. The connection between economic growth and energy use is fundamental in the IEA's present modelling approach. Since our forecast sees little chance of a significant increase in global oil production, our findings suggest that the 'policy makers, investors and end users' to whom WEO 2008 is addressed should rethink their future plans for economic growth. The fact that global oil production has very probably passed its maximum implies that we have reached the Peak of the Oil Age.

Energy efficiency improvements in ammonia production--perspectives and uncertainties

International Nuclear Information System (INIS)

Rafiqul, Islam; Weber, Christoph; Lehmann, Bianca; Voss, Alfred

2005-01-01

The paper discusses the energy consumption and energy saving potential for a major energy-intensive product in the chemical industry-ammonia, based on technologies currently in use and possible process improvements. The paper consists of four parts. In the first part, mainly references to various ammonia production technologies are given. Energy consumption, emissions and saving potentials are discussed in the second part. Thereby, the situation in Europe, the US and India is highlighted and various data sources are compared. In the third part of the paper, a novel approach for modeling energy efficiency improvements is described that accounts for uncertainties and unobserved heterogeneity in the production processes. Besides new investments, revamping investments are also included in the modeling and the development of the production stock is accounted for. Finally, in the fourth part, this approach is applied to the modeling of energy efficiency improvements and CO 2 emission reductions in ammonia production. Thereby, considerable improvements in specific energy use and CO 2 emissions are found in the reference scenario, yet under the assumption of high oil and gas prices, a partial switch to coal based technologies is expected which lowers notably the CO 2 efficiency. Introduction of a CO 2 penalty under a certificate trading or other regime is on contrary found to foster energy efficiency and the use of low carbon technologies

The South African energy scene

International Nuclear Information System (INIS)

Burger, H.T.

1983-01-01

The basic objective of any energy policy is to ensure that the energy-economy of the country developes in accordance with the national interest and promotes national well-being. Energy policies are necessarily based on the tenet of adequate energy availability at acceptable cost levels. Energy policy will evolve in each country to suit the particular circumstances applicable to that country. The overriding aspect of the South African energy policy is the striving towards maximum energy self-sufficiency under secure conditions. This implies maximum reduction and replacement of imported crude oil within financial and manpower constraints. In South Africa energy is not only one of the most important production factors in national economy, but also an important catalyst and stimulus for economic growth and development. The controlled export of energy can be utilized to enhance foreign exchange earnings. The various energy carriers and elements of the South African energy economy can consequently be discussed and evaluated as they are affected by the energy policy guidelines and objectives

Neural Network Based Maximum Power Point Tracking Control with Quadratic Boost Converter for PMSG—Wind Energy Conversion System

Directory of Open Access Journals (Sweden)

Ramji Tiwari

2018-02-01

Full Text Available This paper proposes an artificial neural network (ANN based maximum power point tracking (MPPT control strategy for wind energy conversion system (WECS implemented with a DC/DC converter. The proposed topology utilizes a radial basis function network (RBFN based neural network control strategy to extract the maximum available power from the wind velocity. The results are compared with a classical Perturb and Observe (P&O method and Back propagation network (BPN method. In order to achieve a high voltage rating, the system is implemented with a quadratic boost converter and the performance of the converter is validated with a boost and single ended primary inductance converter (SEPIC. The performance of the MPPT technique along with a DC/DC converter is demonstrated using MATLAB/Simulink.

Utilisation of biomass gasification by-products for onsite energy production.

Science.gov (United States)

Vakalis, S; Sotiropoulos, A; Moustakas, K; Malamis, D; Baratieri, M

2016-06-01

Small scale biomass gasification is a sector with growth and increasing applications owing to the environmental goals of the European Union and the incentivised policies of most European countries. This study addresses two aspects, which are at the centre of attention concerning the operation and development of small scale gasifiers; reuse of waste and increase of energy efficiency. Several authors have denoted that the low electrical efficiency of these systems is the main barrier for further commercial development. In addition, gasification has several by-products that have no further use and are discarded as waste. In the framework of this manuscript, a secondary reactor is introduced and modelled. The main operating principle is the utilisation of char and flue gases for further energy production. These by-products are reformed into secondary producer gas by means of a secondary reactor. In addition, a set of heat exchangers capture the waste heat and optimise the process. This case study is modelled in a MATLAB-Cantera environment. The model is non-stoichiometric and applies the Gibbs minimisation principle. The simulations show that some of the thermal energy is depleted during the process owing to the preheating of flue gases. Nonetheless, the addition of a secondary reactor results in an increase of the electrical power production efficiency and the combined heat and power (CHP) efficiency. © The Author(s) 2016.

The impact of energy prices on industrial energy efficiency and productivity

International Nuclear Information System (INIS)

Boyd, G.A.

1993-01-01

Energy prices moved into the forefront of concern in the mid and late seventies when two oil price shocks drove up energy prices dramatically. The analysis of the subsequent increase in industrial energy efficiency, i.e., decline in energy use per unit of industrial output, has filled volumes of government and private studies. Despite the volumes of analysis, there remains no consensus on the magnitude of the effect of energy prices on industrial energy efficiency or the effect of the change in energy prices on productivity. This paper examines some sources of the controversy to initiate a dialog between policy makers, analysts, and the energy consumers and producers

Maximum Power Tracking by VSAS approach for Wind Turbine, Renewable Energy Sources

Directory of Open Access Journals (Sweden)

Nacer Kouider Msirdi

2015-08-01

Full Text Available This paper gives a review of the most efficient algorithms designed to track the maximum power point (MPP for catching the maximum wind power by a variable speed wind turbine (VSWT. We then design a new maximum power point tracking (MPPT algorithm using the Variable Structure Automatic Systems approach (VSAS. The proposed approachleads efficient algorithms as shown in this paper by the analysis and simulations.

DEPENDENCE OF ENERGY EFFICIENCY AND COST OF PRODUCTION

Directory of Open Access Journals (Sweden)

D. Sklyarov

2016-01-01

Full Text Available Economic systems exist on condition of receipt and spending of energy. Energy consumption is a necessary condition for the existence and functioning of the economic systems of any scale: macroeconomics, microeconomics, regional economy or the world economy.The economic system operates on the scale at which it is able to produce energy and get access to energy. Moreover, receipt and consumption of energy in the operation of the economic system is mainly determined by, the level of energy production from energy sources, since this level is determined by the level of energy consumption by industries and enterprises of the economy.Currently, the economic system does not produce energy in reserve. Thus, the question of energy effi ciency and energy saving was always acute.The article describes the energy efficiency and energy saving effect on the cost of production. Were used two methods: “costs and release” matrix and “price - value added” matrix. The result is the equation of dependence of energy efficiency and costs.

78 FR 9631 - Energy Efficiency Program for Consumer Products: Energy Conservation Standards for Residential...

Science.gov (United States)

2013-02-11

... Efficiency Program for Consumer Products: Energy Conservation Standards for Residential Boilers AGENCY: Office of Energy Efficiency and Renewable Energy, Department of Energy. ACTION: Notice of public meeting.... Department of Energy, Office of Energy Efficiency and Renewable Energy, Building Technologies Program, EE-2J...

Sources of energy productivity change in China during 1997–2012: A decomposition analysis based on the Luenberger productivity indicator

International Nuclear Information System (INIS)

Wang, Ke; Wei, Yi-Ming

2016-01-01

Given that different energy inputs play different roles in production and that energy policy decision making requires an evaluation of productivity change in individual energy input to provide insight into the scope for improvement of the utilization of specific energy input, this study develops, based on the Luenberger productivity indicator and data envelopment analysis models, an aggregated specific energy productivity indicator combining the individual energy input productivity indicators that account for the contributions of each specific energy input toward energy productivity change. In addition, these indicators can be further decomposed into four factors: pure efficiency change, scale efficiency change, pure technology change, and scale of technology change. These decompositions enable a determination of which specific energy input is the driving force of energy productivity change and which of the four factors is the primary contributor of energy productivity change. An empirical analysis of China's energy productivity change over the period 1997–2012 indicates that (i) China's energy productivity growth may be overestimated if energy consumption structure is omitted; (ii) in regard to the contribution of specific energy input toward energy productivity growth, oil and electricity show positive contributions, but coal and natural gas show negative contributions; (iii) energy-specific productivity changes are mainly caused by technical changes rather than efficiency changes; and (iv) the Porter Hypothesis is partially supported in China that carbon emissions control regulations may lead to energy productivity growth. - Highlights: • An energy input specific Luenberger productivity indicator is proposed. • It enables to examine the contribution of specific energy input productivity change. • It can be decomposed for identifying pure and scale efficiency changes, as well as pure and scale technical changes. • China's energy productivity growth may

Power production and energy consumption in Norway

International Nuclear Information System (INIS)

2001-03-01

The main electrical resource of Norway comes from its rivers: 99% of the electric power is produced by hydroelectric power plants. Other sources, like wind and natural gas, are envisaged for the enhancement of Norway's energy production capacity. In this document, the part devoted to power production presents the different electricity production sources and their impact on the Norwegian economy. The energy consumption is detailed in the third part with an historical review of its evolution and a description of the main sectors involved in this consumption. The forth part describes the main actors of the energy sector with their industrial structure, the research institutes and universities performing R and D in this domain, and the energy trades with surrounding countries. The fifth part stresses on the research projects, on the government promoting actions through the Norwegian Research Council, and gives some examples of todays research projects. The sixth part deals with international cooperation in the R and D domain with a particular attention given to the relations between Norway, France and Europe. (J.S.)

Application of advanced methods for the prognosis of production energy consumption

International Nuclear Information System (INIS)

Stetter, R; Witczak, P; Spindler, C; Hertel, J; Staiger, B

2014-01-01

This paper, based on a current research project, describes the application of advanced methods that are frequently used in fault-tolerance control and addresses the issue of the prognosis of energy efficiency. Today, the energy a product requires during its operation is the subject of many activities in research and development. However, the energy necessary for the production of goods is very often not analysed in comparable depth. In the field of electronics, studies come to the conclusion that about 80% of the total energy used by a product is from its production [1]. The energy consumption in production is determined very early in the product development process by designers and engineers, for example through selection of raw materials, explicit and implicit requirements concerning the manufacturing and assembly processes, or through decisions concerning the product architecture. Today, developers and engineers have at their disposal manifold design and simulation tools which can help to predict the energy consumption during operation relatively accurately. In contrast, tools with the objective to predict the energy consumption in production and disposal are not available. This paper aims to present an explorative study of the use of methods such as Fuzzy Logic to predict the production energy consumption early in the product development process

Calendar Year 2008 Program Benefits for ENERGY STAR Labeled Products

Energy Technology Data Exchange (ETDEWEB)

Homan, GregoryK; Sanchez, Marla; Brown, RichardE; Lai, Judy

2010-08-24

This paper presents current and projected savings for ENERGY STAR labeled products, and details the status of the model as implemented in the September 2009 spreadsheets. ENERGY STAR is a voluntary energy efficiency labeling program operated jointly by the Environmental Protection Agency (US EPA) and the U.S. Department of Energy (US DOE), designed to identify and promote energy-efficient products, buildings and practices. Since the program inception in 1992, ENERGY STAR has become a leading international brand for energy efficient products, and currently labels more than thirty products, spanning office equipment, heating, cooling and ventilation equipment, commercial and residential lighting, home electronics, and major appliances. ENERGY STAR's central role in the development of regional, national and international energy programs necessitates an open process whereby its program achievements to date as well as projected future savings are shared with stakeholders. This report presents savings estimates for ENERGY STAR labeled products. We present estimates of energy, dollar, and carbon savings achieved by the program in the year 2008, annual forecasts for 2009 and 2010, and cumulative savings estimates for the period 1993 through 2008 and cumulative forecasts for the period 2009 through 2015. Through 2008 the program saved 8.8 Quads of primary energy and avoided the equivalent of 158 metric tones carbon (MtC). The forecast for the period 2009-2015 is 18.1 Quads or primary energy saved and 316 MtC emissions avoided. The sensitivity analysis bounds the best estimate of carbon avoided between 104 MtC and 213 MtC (1993 to 2008) and between 206 MtC and 444 MtC (2009 to 2015). In this report we address the following questions for ENERGY STAR labeled products: (1) How are ENERGY STAR impacts quantified; (2) What are the ENERGY STAR achievements; and (3) What are the limitations to our method?

Energy requirement and economic analysis of citrus production in Turkey

Energy Technology Data Exchange (ETDEWEB)

Ozkan, Burhan E-mail: bozkan@akdeniz.edu.tr; Akcaoz, Handan; Karadeniz, Feyza

2004-07-01

The aim of this research was to examine the energy requirements of the inputs and output in citrus production in the Antalya province of Turkey. Data for the production of citrus fruits (orange, lemon and mandarin) were collected from 105 citrus farms by using a face to face questionnaire method. The research results revealed that lemon production was the most energy intensive among the three fruits investigated. The energy input of chemical fertilizer (49.68%), mainly nitrogen, has the biggest share in the total energy inputs followed by Diesel (30.79%). The lemon production consumed a total of 62 977.87 MJ/ha followed by orange and mandarin with 60 949.69 and 48 838.17 MJ/ha, respectively. The energy ratios for orange, mandarin and lemon were estimated to be 1.25, 1.17 and 1.06, respectively. On average, the non-renewable form of energy input was 95.90% of the total energy input used in citrus production compared to only 3.74% for the renewable form. The benefit-cost ratio was the highest in orange production (2.37) followed by lemon. The results indicate that orange production in the research area is most remunerative to growers compared to lemon and mandarin.

Energy use and gross margin analysis for sesame production in ...

African Journals Online (AJOL)

As the negative impacts of energy by-products affect the climate, the knowledge and efficient use of energy in crop production will minimise environmental problems and promote sustainable agriculture as an economic production system in Nigeria and else where. The aim of the study was to evaluate energy use and gross ...

Influence of epoxy resin as encapsulation material of silicon photovoltaic cells on maximum current

Directory of Open Access Journals (Sweden)

Acevedo-Gómez David

2017-01-01

Full Text Available This work presents an analysis about how the performance of silicon photovoltaic cells is influenced by the use of epoxy resin as encapsulation material with flat roughness. The effect of encapsulation on current at maximum power of mono-crystalline cell was tested indoor in a solar simulator bench at 1000 w/m² and AM1.5G. The results show that implementation of flat roughness layer onto cell surface reduces the maximum current inducing on average 2.7% less power with respect to a cell before any encapsulation. The losses of power and, in consequence, the less production of energy are explained by resin light absorption, reflection and partially neutralization of non-reflective coating.

Periodic variations of Auger energy maximum distribution following He{sup 2+} + H{sub 2} collisions: A complete analogy with photon interferences

Energy Technology Data Exchange (ETDEWEB)

Cholet, M.; Minerbe, F.; Oliviero, G.; Pestel, V. [Université de Caen, 6 bd du Mal Juin, 14050 Caen Cedex (France); Frémont, F., E-mail: francois.fremont@ensicaen.fr [Centre de Recherche sur les Ions, les Matériaux et la Photonique, Unité Mixte Université de Caen-CEA-CNRS-EnsiCaen, 6 bd du Mal Juin, 14050 Caen Cedex 4 (France)

2014-08-15

Highlights: • Young type interferences with electrons are revisited. • Oscillations in the angular distribution of the energy maximum of Auger spectra are evidenced. • Model calculations are in good agreement with the experimental result. • The position of the Auger spectra oscillates in counterphase with the total intensity. - Abstract: In this article, we present experimental evidence of a particular electron-interference phenomenon. The electrons are provided by autoionization of 2l2l′ doubly excited He atoms following the capture of H{sub 2} electrons by a slow He{sup 2+} incoming ion. We observe that the position of the energy maximum of the Auger structures oscillates with the detection angle. Calculation based on a simple model that includes interferences clearly shows that the present oscillations are due to Young-type interferences caused by electrons scattering on both H{sup +} centers.

Towards a more efficient energy use in photovoltaic powered products

NARCIS (Netherlands)

Kan, S.Y.; Strijk, R.

2006-01-01

This paper analyzes the energy saving and power management solutions necessary to improve the energy consumption efficiency in photovoltaic powered products. Important in the design of such products is not only the energy supply optimization required to deliver the actual energy to fulfil their

Environmental policy and the energy efficiency of vertically differentiated consumer products

International Nuclear Information System (INIS)

Brzeskot, Magdalena; Haupt, Alexander

2013-01-01

We analyse optimal environmental policies in a market that is vertically differentiated in terms of the energy efficiency of products. Considering energy taxes, subsidies to firms for investment in more eco-friendly products, and product standards, we are particularly interested in how distributional goals in addition to environmental goals shape the choice of policy instruments. We find that an industry-friendly government levies an energy tax to supplement a lax product standard, but shies away from subsidies to firms. By contrast, a consumer-friendly government relies heavily on a strict product standard and additionally implements a moderate subsidy to firms, but avoids energy taxes. - Highlights: ► We analyse how distributional goals shape environmental policy. ► Firms invest in the energy efficiency of their products and compete in prices. ► An industry-friendly government implements an energy tax and a lax product standard. ► A consumer-friendly government chooses a subsidy to firms instead of an energy tax. ► A consumer-friendly government implements a strict energy efficiency standard

77 FR 38743 - Energy Efficiency Program for Consumer Products: Energy Conservation Standards for Battery...

Science.gov (United States)

2012-06-29

... Efficiency Program for Consumer Products: Energy Conservation Standards for Battery Chargers and External Power Supplies AGENCY: Office of Energy Efficiency and Renewable Energy, Department of Energy. ACTION... Energy Efficiency and Renewable Energy, Building Technologies Program, EE-2J, 1000 Independence Avenue SW...

Assessment of energy return on energy investment (EROEI) of oil bearing crops for renewable fuel production

OpenAIRE

A. Restuccia; S. Failla; D. Longo; L. Caruso; I. Mallia; G. Schillaci

2013-01-01

As reported in literature the production of biodiesel should lead to a lower energy consumption than those obtainable with its use. So, to justify its consumption, a sustainable and “low input” production should be carried out. In order to assess the sustainability of Linum usitatissimum, Camelina sativa and Brassica carinata cultivation for biodiesel production in terms of energy used compared to that obtained, the index EROEI (Energy Return On Energy Invested) has been used. At this aim, an...

Particle Swarm Optimization Based of the Maximum Photovoltaic ...

African Journals Online (AJOL)

Photovoltaic electricity is seen as an important source of renewable energy. The photovoltaic array is an unstable source of power since the peak power point depends on the temperature and the irradiation level. A maximum peak power point tracking is then necessary for maximum efficiency. In this work, a Particle Swarm ...

Trade-facilitated technology spillovers in energy productivity convergence processes across EU countries

International Nuclear Information System (INIS)

Wan, Jun; Baylis, Kathy; Mulder, Peter

2015-01-01

This empirical paper tests for trade-facilitated spillovers in the convergence of energy productivity across 16 European Union (EU) countries from 1995 to 2005. One might anticipate that by inducing specialization, trade limits the potential for convergence in energy productivity. Conversely, by inducing competition and knowledge diffusion, trade may spur sectors to greater energy productivity. Unlike most previous work on convergence, we explain productivity dynamics from cross-country interactions at a detailed sector level and apply a spatial panel data approach to explicitly account for trade-flow related spatial effects in the convergence analysis. Our study confirms the existence of convergence in manufacturing energy productivity, caused by efficiency improvements in lagging countries, while undermined by increasing international differences in sector structure. Further, we find that trade flows explain 30 to 40% of the unobserved variation in energy productivity. Trade continues to explain the unobserved variation in energy productivity even after accounting for geographic proximity. Last, we find that those countries and sectors with higher dependence on trade both have higher energy productivity growth and a higher rate of convergence, further implying that trade can enhance energy productivity. Thus, unlike concerns that trade may spur a ‘race to the bottom’, we find that promoting trade may help stimulate energy efficiency improvements across countries. - Highlights: • We test for trade-facilitated spillovers in cross-country energy productivity convergence. • We use a spatial panel-data approach and data for 16 European Union countries. • Efficiency improvements in lagging countries cause energy productivity convergence. • Trade flows explain 30 to 40% of unobserved variation in energy productivity. • Higher dependence on trade means higher rates of energy productivity growth

Ethylene Production Maximum Achievable Control Technology (MACT) Compliance Manual

Science.gov (United States)

This July 2006 document is intended to help owners and operators of ethylene processes understand and comply with EPA's maximum achievable control technology standards promulgated on July 12, 2002, as amended on April 13, 2005 and April 20, 2006.

The US department of energy programme on hydrogen production

International Nuclear Information System (INIS)

Paster, M.D.

2004-01-01

Clean forms of energy are needed to support sustainable global economic growth while mitigating greenhouse gas emissions and impacts on air quality. To address these challenges, the U.S. President's National Energy Policy and the U.S. Department of Energy's (DOE's) Strategic Plan call for expanding the development of diverse domestic energy supplies. Working with industry, the Department developed a national vision for moving toward a hydrogen economy - a solution that holds the potential to provide sustainable clean, safe, secure, affordable, and reliable energy. In February 2003, President George W. Bush announced a new Hydrogen Fuel Initiative to achieve this vision. To realize this vision, the U.S. must develop and demonstrate advanced technologies for hydrogen production, delivery, storage, conversion, and applications. Toward this end, the DOE has worked with public and private organizations to develop a National Hydrogen Energy Technology Road-map. The Road-map identifies the technological research, development, and demonstration steps required to make a successful transition to a hydrogen economy. One of the advantages of hydrogen is that it can utilize a variety of feedstocks and a variety of production technologies. Feedstock options include fossil resources such as coal, natural gas, and oil, and non-fossil resources such as biomass and water. Production technologies include thermochemical, biological, electrolytic and photolytic processes. Energy needed for these processes can be supplied through fossil, renewable, or nuclear sources. Hydrogen can be produced in large central facilities and distributed to its point of use or it can be produced in a distributed manner in small volumes at the point of use such as a refueling station or stationary power facility. In the shorter term, distributed production will play an important role in initiating the use of hydrogen due to its lower capital investment. In the longer term, it is likely that centralized

Water Use of Fossil Energy Production and Supply in China

Directory of Open Access Journals (Sweden)

Gang Lin

2017-07-01

Full Text Available Fossil energy and water resources are both important for economic and social development in China, and they are tightly interlinked. Fossil energy production consumes large amounts of water, and it is essential to investigate the water footprint of fossil energy production (WFEP in China. In addition, fossil energy is supplied to consumers in China by both domestic and foreign producers, and understanding the water footprint of fossil energy supply (WFES is also highly significant for water and energy development programs in the long-term. The objectives of this paper were to provide an estimation of the blue component of WFEP and WFES in China for the period from 2001 to 2014, and to evaluate the impact on water resources from energy production, the contribution of internal and external WFES, and water-energy related issues of the international energy trade by applying water footprint analysis based on the bottom-up approach. The results indicate that generally, the WFEP and WFES in China both maintained steady growth before 2013, with the WFEP increasing from approximately 3900 million m3/year to 10,400 million m3/year, while the WFES grew from 3900 million m3/year to 11,600 million m3/year. The fossil energy production caps of the 13th Five Year Plan can bring the water consumed for fossil energy production back to a sustainable level. Over the long-term, China’s energy trade plan should also consider the water and energy resources of the countries from which fossil energy is imported.

Nuclear Energy - Hydrogen Production - Fuel Cell: A Road Towards Future China's Sustainable Energy Strategy

International Nuclear Information System (INIS)

Zhiwei Zhou

2006-01-01

Sustainable development of Chinese economy in 21. century will mainly rely on self-supply of clean energy with indigenous natural resources. The burden of current coal-dominant energy mix and the environmental stress due to energy consumptions has led nuclear power to be an indispensable choice for further expanding electricity generation capacity in China and for reducing greenhouse effect gases emission. The application of nuclear energy in producing substitutive fuels for road transportation vehicles will also be of importance in future China's sustainable energy strategy. This paper illustrates the current status of China's energy supply and the energy demand required for establishing a harmonic and prosperous society in China. In fact China's energy market faces following three major challenges, namely (1) gaps between energy supply and demand; (2) low efficiency in energy utilization, and (3) severe environmental pollution. This study emphasizes that China should implement sustainable energy development policy and pay great attention to the construction of energy saving recycle economy. Based on current forecast, the nuclear energy development in China will encounter a high-speed track. The demand for crude oil will reach 400-450 million tons in 2020 in which Chinese indigenous production will remain 180 million tons. The increase of the expected crude oil will be about 150 million tons on the basis of 117 million tons of imported oil in 2004 with the time span of 15 years. This demand increase of crude oil certainly will influence China's energy supply security and to find the substitution will be a big challenge to Chinese energy industry. This study illustrates an analysis of the market demands to future hydrogen economy of China. Based on current status of technology development of HTGR in China, this study describes a road of hydrogen production with nuclear energy. The possible technology choices in relation to a number of types of nuclear reactors are

Particle production at collider energies

International Nuclear Information System (INIS)

Geich-Gimbel, C.

1987-11-01

Key features of the SPS panti p Collider and the detectors of the UA-experiments involved are dealt with in chapter 2, which includes and accord to the ramping mode of the Collider, which allowed to raise the c.m. energy to 900 GeV in the UA5/2 experiment. The following chapters concentrate on physics results. Starting with a discussion of cross sections and diffraction dissociation in chapter 3 we then continue with a presentation of basic features of particle production such as rapidity and multiplicity distributions in chapter 4. There one of the unexpected findings at Collider energies, the breakdown of the so-called KNO-scaling, and new regularities potentially governing multiplicity distributions, are discussed. The findings about correlations among the final state particles, which may tell about the underlying dynamics of multi-particle production and be relevant to models thereof, are described in due detail in chapter 5. Transverse spectra and their trends with energy are shown in chapter 6. Results on identified particles are collected in a separate chapter in order to stress that this piece of information was an important outcome of the UA5 experiment. (orig./HSI)

Towards nuclear energy applications other than electricity production

International Nuclear Information System (INIS)

Lecomte, M.

2007-01-01

Use of nuclear energy relies on operation of a boiler, involving practically no greenhouse gas emission. Whereas production of electricity is, nowadays, virtually its sole purpose, demand for heat production could equally arise, particularly with the emergence of high-temperature, or even very-high-temperature reactors. With the abilities this involves, as regards the recovery of heavy crude oils from tar sands, seawater desalination, or, most importantly, production of hydrogen by electrolysis, or thermochemistry, this being the energy carrier of tomorrow. (authors)

Estimating the maximum potential revenue for grid connected electricity storage :

Energy Technology Data Exchange (ETDEWEB)

Byrne, Raymond Harry; Silva Monroy, Cesar Augusto.

2012-12-01

The valuation of an electricity storage device is based on the expected future cash flow generated by the device. Two potential sources of income for an electricity storage system are energy arbitrage and participation in the frequency regulation market. Energy arbitrage refers to purchasing (stor- ing) energy when electricity prices are low, and selling (discharging) energy when electricity prices are high. Frequency regulation is an ancillary service geared towards maintaining system frequency, and is typically procured by the independent system operator in some type of market. This paper outlines the calculations required to estimate the maximum potential revenue from participating in these two activities. First, a mathematical model is presented for the state of charge as a function of the storage device parameters and the quantities of electricity purchased/sold as well as the quantities o ered into the regulation market. Using this mathematical model, we present a linear programming optimization approach to calculating the maximum potential revenue from an elec- tricity storage device. The calculation of the maximum potential revenue is critical in developing an upper bound on the value of storage, as a benchmark for evaluating potential trading strate- gies, and a tool for capital nance risk assessment. Then, we use historical California Independent System Operator (CAISO) data from 2010-2011 to evaluate the maximum potential revenue from the Tehachapi wind energy storage project, an American Recovery and Reinvestment Act of 2009 (ARRA) energy storage demonstration project. We investigate the maximum potential revenue from two di erent scenarios: arbitrage only and arbitrage combined with the regulation market. Our analysis shows that participation in the regulation market produces four times the revenue compared to arbitrage in the CAISO market using 2010 and 2011 data. Then we evaluate several trading strategies to illustrate how they compare to the

Forecasting forest chip energy production in Finland 2008-2014

International Nuclear Information System (INIS)

Linden, Mikael

2011-01-01

Energy policy measures aim to increase energy production from forest chips in Finland to 10 TWh by year 2010. However, on the regional level production differences are large, and the regional estimates of the potential base of raw materials for the production of forest chips are heterogeneous. In order to analyse the validity of the above target, two methods are proposed to derive forecasts for region-level energy production from forest chips in Finland in the years 2008-2014. The plant-level data from 2003-2007 gives a starting point for a detailed statistical analysis of present and future region-level forest chip production. Observed 2008 regional levels are above the estimated prediction 95% confidence intervals based on aggregation of plant-level time averages. A simple time trend model with fixed-region effects provides accurate forecasts for the years 2008-2014. Forest chip production forecast confidence intervals cover almost all regions for the 2008 levels and the estimates of potential production levels for 2014. The forecast confidence intervals are also derived with re-sampling methods, i.e. with bootstrap methods, to obtain more reliable results. Results confirm that a general materials shortfall is not expected in the near future for forest chip energy production in Finland.

Biochemical and photosynthetic aspects of energy production

Energy Technology Data Exchange (ETDEWEB)

San Pietro, A [ed.

1980-01-01

Photosynthesis is the only method of solar energy conversion presently practiced on a large scale, supplying all food energy as well as fiber and wood. This book is an attempt to describe and evaluate biological processes that may serve in the future to provide alternative energy resources. Areas covered include marine biomass production, algal-bacterial systems, agricultural residues, energy farming and biological nitrogen fixation with an emphasis on the legumes.

Energy-efficient approach to minimizing the energy consumption in an extended job-shop scheduling problem

Science.gov (United States)

Tang, Dunbing; Dai, Min

2015-09-01

The traditional production planning and scheduling problems consider performance indicators like time, cost and quality as optimization objectives in manufacturing processes. However, environmentally-friendly factors like energy consumption of production have not been completely taken into consideration. Against this background, this paper addresses an approach to modify a given schedule generated by a production planning and scheduling system in a job shop floor, where machine tools can work at different cutting speeds. It can adjust the cutting speeds of the operations while keeping the original assignment and processing sequence of operations of each job fixed in order to obtain energy savings. First, the proposed approach, based on a mixed integer programming mathematical model, changes the total idle time of the given schedule to minimize energy consumption in the job shop floor while accepting the optimal solution of the scheduling objective, makespan. Then, a genetic-simulated annealing algorithm is used to explore the optimal solution due to the fact that the problem is strongly NP-hard. Finally, the effectiveness of the approach is performed smalland large-size instances, respectively. The experimental results show that the approach can save 5%-10% of the average energy consumption while accepting the optimal solution of the makespan in small-size instances. In addition, the average maximum energy saving ratio can reach to 13%. And it can save approximately 1%-4% of the average energy consumption and approximately 2.4% of the average maximum energy while accepting the near-optimal solution of the makespan in large-size instances. The proposed research provides an interesting point to explore an energy-aware schedule optimization for a traditional production planning and scheduling problem.

A consistent high primary production and chlorophyll-a maximum in a narrow strait – effects of hydraulic control

DEFF Research Database (Denmark)

Lund-Hansen, Lars Chresten; Nielsen, Morten Holtegaard; Bruhn, Annette

2008-01-01

and the North Sea. The time-series were supplemented with Scan Fish transects — a towed CTD, ADCP measurements, and nutrient data. There is a significant maximum in primary production (mg C m− 2 day− 1) in central LB, which is 30% higher than outside the LB region. Chl-a concentrations are 30% higher in central...

76 FR 13168 - Energy Conservation Program for Consumer Products: Representative Average Unit Costs of Energy

Science.gov (United States)

2011-03-10

... average unit costs of residential energy in a Federal Register notice entitled, ``Energy Conservation... DEPARTMENT OF ENERGY Office of Energy Efficiency and Renewable Energy Energy Conservation Program for Consumer Products: Representative Average Unit Costs of Energy AGENCY: Office of Energy Efficiency...

Hydrogen production from water: Recent advances in photosynthesis research

Energy Technology Data Exchange (ETDEWEB)

Greenbaum, E.; Lee, J.W. [Oak Ridge National Lab., TN (United States). Chemical Technology Div.

1997-12-31

The great potential of hydrogen production by microalgal water splitting is predicated on quantitative measurement of the algae`s hydrogen-producing capability, which is based on the following: (1) the photosynthetic unit size of hydrogen production; (2) the turnover time of photosynthetic hydrogen production; (3) thermodynamic efficiencies of conversion of light energy into the Gibbs free energy of molecular hydrogen; (4) photosynthetic hydrogen production from sea water using marine algae; (5) the potential for research advances using modern methods of molecular biology and genetic engineering to maximize hydrogen production. ORNL has shown that sustained simultaneous photoevolution of molecular hydrogen and oxygen can be performed with mutants of the green alga Chlamydomonas reinhardtii that lack a detectable level of the Photosystem I light reaction. This result is surprising in view of the standard two-light reaction model of photosynthesis and has interesting scientific and technological implications. This ORNL discovery also has potentially important implications for maximum thermodynamic conversion efficiency of light energy into chemical energy by green plant photosynthesis. Hydrogen production performed by a single light reaction, as opposed to two, implies a doubling of the theoretically maximum thermodynamic conversion efficiency from {approx}10% to {approx}20%.

Future materials requirements for the high-energy-intensity production of aluminum

Science.gov (United States)

Welch, B. J.; Hyland, M. M.; James, B. J.

2001-02-01

Like all metallurgical industries, aluminum smelting has been under pressure from two fronts—to give maximum return on investment to the shareholders and to comply with environmental regulations by reducing greenhouse emissions. The smelting process has advanced by improving efficiency and productivity while continuing to seek new ways to extend the cell life. Materials selection (particularly the use of more graphitized cathodic electrodes) has enabled lower energy consumption, while optimization of the process and controlling in a narrow band has enabled increases in productivity and operations at higher current densities. These changes have, in turn, severely stressed the materials used for cell construction, and new problems are emerging that are resulting in a reduction of cell life. The target for aluminum electro-winning has been to develop an oxygen-evolving electrode, rather than one that evolves substantial amounts of carbon dioxide. Such an electrode, when combined with suitable wettable cathode material developments, would reduce operating costs by eliminating the need for frequent electrode change and would enable more productive cell designs and reduce plant size. The materials specifications for developing these are, however, an extreme challenge. Those specifications include minimized corrosion rate of any electrode into the electrolyte, maintaining an electronically conducting oxidized surface that is of low electrical resistance, meeting the metal purity targets, and enabling variable operating current densities. Although the materials specifications can readily be written, the processing and production of the materials is the challenge.

Assessment of energy return on energy investment (EROEI of oil bearing crops for renewable fuel production

Directory of Open Access Journals (Sweden)

A. Restuccia

2013-09-01

Full Text Available As reported in literature the production of biodiesel should lead to a lower energy consumption than those obtainable with its use. So, to justify its consumption, a sustainable and “low input” production should be carried out. In order to assess the sustainability of Linum usitatissimum, Camelina sativa and Brassica carinata cultivation for biodiesel production in terms of energy used compared to that obtained, the index EROEI (Energy Return On Energy Invested has been used. At this aim, an experimental field was realised in the south-eastern Sicilian land. During the autumn-winter crop cycle, no irrigation was carried out and some suitable agricultural practices have been carried out taking into account the peculiarity of each type of used seeds. The total energy consumed for the cultivation of oil bearing crops from sowing to the production of biodiesel represents the Input of the process. In particular, this concerned the energy embodied in machinery and tools utilized, in seed, chemical fertilizer and herbicide but also the energy embodied in diesel fuels and lubricant oils. In addition, the energy consumption relating to machines and reagents required for the processes of extraction and transesterification of the vegetable oil into biodiesel have been calculated for each crops. The energy obtainable from biodiesel production, taking into account the energy used for seed pressing and for vegetable oil transesterification into biodiesel, represents the Output of the process. The ratio Output/Input gets the EROEI index which in the case of Camelina sativa and Linum usatissimum is greater than one. These results show that the cultivation of these crops for biofuels production is convenient in terms of energy return on energy investment. The EROEI index for Brassica carinata is lower than one. This could means that some factors, concerning mechanisation and climatic

Assessment of building integrated energy supply and energy saving schemes on a national level in Denmark

Energy Technology Data Exchange (ETDEWEB)

Muenster, M.; Morthorst, P.E.; Birkl, C.

2011-06-15

In the future, buildings will not only act as consumers of energy but as producers as well. For these ''prosumers'', energy production by use of solar panels, photovoltaics and heat pumps etc will be essential. The objective of this project was to find the most optimal combinations of building insulation and use of renewable energy sources in existing buildings in terms of economics and climate impacts. Five houses were analyzed based on different personal load, consumption profiles, solar orientation and proposed building envelope improvements and use of combinations of renewable energy systems. The results of these analyses were integrated in five scenarios to examine the consequences at national level of implementing insulation together with solar panels, photovoltaics and heat pumps in single-family houses. The simulations focused on the building period between 1961 and 1972 characterised by high building activity and low energy performance. The five scenarios - a baseline scenario, a maximum savings scenario, a maximum production scenario, and a combination scenario - showed that regardless of scenario, a consequent use of individual heat pumps leads to the greatest energy savings and CO{sub 2} reductions. (ln)

Maximum Safety Regenerative Power Tracking for DC Traction Power Systems

Directory of Open Access Journals (Sweden)

Guifu Du

2017-02-01

Full Text Available Direct current (DC traction power systems are widely used in metro transport systems, with running rails usually being used as return conductors. When traction current flows through the running rails, a potential voltage known as “rail potential” is generated between the rails and ground. Currently, abnormal rises of rail potential exist in many railway lines during the operation of railway systems. Excessively high rail potentials pose a threat to human life and to devices connected to the rails. In this paper, the effect of regenerative power distribution on rail potential is analyzed. Maximum safety regenerative power tracking is proposed for the control of maximum absolute rail potential and energy consumption during the operation of DC traction power systems. The dwell time of multiple trains at each station and the trigger voltage of the regenerative energy absorbing device (READ are optimized based on an improved particle swarm optimization (PSO algorithm to manage the distribution of regenerative power. In this way, the maximum absolute rail potential and energy consumption of DC traction power systems can be reduced. The operation data of Guangzhou Metro Line 2 are used in the simulations, and the results show that the scheme can reduce the maximum absolute rail potential and energy consumption effectively and guarantee the safety in energy saving of DC traction power systems.

Environmental assessment for the Consumer Products Efficiency Standards program

Energy Technology Data Exchange (ETDEWEB)

1980-05-23

The Energy Policy and Conservation Act of 1975 as amended by the National Energy Conservation Policy Act of 1978, requires the DOE to prescribe energy efficiency standards for thirteen consumer products. The Consumer Products Efficiency Standards (CPES) program covers the following products: refrigerators and refrigerator-freezers; freezers;clothes dryers;water heaters; room air conditioners; home heating equipment (not including furnaces); kitchen ranges and ovens; central air conditioners (cooling and heat pumps); furnaces; dishwashers; television sets; clothes washers; and humidifiers and dehumidifiers. DOE is proposing two sets of standards for all thirteen consumer products: intermediate standards to become effective in 1981 for the first nine products and in 1982 for the second four products, and final standards to become effective in 1986 and 1987, respectively. The final standards are more restrictive than the intermediate standards and will provide manufacturers with the maximum time permitted under the Act to plan and develop extensive new lines of efficient consumer products. The final standards proposed by DOE require the maximum improvements in efficiency which are technologically feasible and economically justified, as required by Section 325(c) of EPCA. The thirteen consumer products account for approximately 90% of all the energy consumed in the nation's residences, or more than 20% of the nation's energy needs. Increases in the energy efficiency of these consumer products can help to narrow the gap between the nation's increasing demand for energy and decreasing supplies of domestic oil and natural gas. Improvements in the efficiency of consumer products can thus help to solve the nation's energy crisis.

Waste incineration with production of clean and reliable energy

Energy Technology Data Exchange (ETDEWEB)

Pavlas, Martin; Tous, Michal; Klimek, Petr; Bebar, Ladislav [Brno University of Technology, Department of Process and Environmental Engineering (UPEI VUT Brno), Brno (Czech Republic)

2011-08-15

Discussion about utilization of waste for energy production (waste-to-energy, WTE) has moved on to next development phase. Waste fired power plants are discussed and investigated. These facilities focus on electricity production whereas heat supply is diminished and operations are not limited by insufficient heat demand. Present results of simulation prove that increase of net electrical efficiency above 20% for units processing 100 kt/year (the most common ones) is problematic and tightly bound with increased investments. Very low useful heat production in Rankine-cycle based cogeneration system with standard steam parameters leads to ineffective utilization of energy. This is documented in this article with the help of newly developed methodology based on primary energy savings evaluation. This approach is confronted with common method for energy recovery efficiency evaluation required by EU legislation (Energy Efficiency - R1 Criteria). New term highly-efficient WTE is proposed and condition under which is the incinerator classified as highly efficient are specified and analyzed. Once sole electricity production is compelled by limited local heat demand, application of non-conventional arrangements is highly beneficial to secure effective energy utilization. In the paper a system where municipal solid waste incinerator is integrated with combined gas-steam cycle is evaluated in the same manner. (orig.)

Tool life and cutting speed for the maximum productivity at the drilling of the stainless steel X22CrMoV12-1

Science.gov (United States)

Vlase, A.; Blăjină, O.; Iacob, M.; Darie, V.

2015-11-01

Two addressed issues in the research regarding the cutting machinability, establishing of the optimum cutting processing conditions and the optimum cutting regime, do not yet have sufficient data for solving. For this reason, in the paper it is proposed the optimization of the tool life and the cutting speed at the drilling of a certain stainless steel in terms of the maximum productivity. For this purpose, a nonlinear programming mathematical model to maximize the productivity at the drilling of the steel is developed in the paper. The optimum cutting tool life and the associated cutting tool speed are obtained by solving the numerical mathematical model. Using this proposed model allows increasing the accuracy in the prediction of the productivity for the drilling of a certain stainless steel and getting the optimum tool life and the optimum cutting speed for the maximum productivity. The results presented in this paper can be used in the production activity, in order to increase the productivity of the stainless steels machining. Also new research directions for the specialists in this interested field may come off from this paper.

Renewable energy production by photoelectrochemical oxidation of organic wastes using WO3 photoanodes.

Science.gov (United States)

Raptis, Dimitrios; Dracopoulos, Vassilios; Lianos, Panagiotis

2017-07-05

The present work has studied renewable hydrogen production by photoelectrocatalytic degradation of model organic substances representing biomass derived organic wastes. Its purpose was to show that renewable energy can be produced by consuming wastes. The study has been carried out by employing nanoparticulate WO 3 photoanodes in the presence of ethanol, glycerol or sorbitol, i.e. three substances which are among typical biomass products. In these substances, the molecular weight and the number of hydroxyl groups increases from ethanol to sorbitol. The photocurrent produced by the cell was the highest in the presence of ethanol, smaller in the case of glycerol and further decreased in the presence of sorbitol. The photocurrent was roughly the double of that produced in the absence of an organic additive thus demonstrating current doubling phenomena. Hydrogen was produced only under illumination and was monitored at two forward bias, 0.8 and 1.6V vs Ag/AgCl. Hydrogen production rates followed the same order as the photocurrent thus indicating that hydrogen production by reduction of protons mainly depends on the current flowing through the external circuit connecting photoanode with cathode. The maximum solar-to-hydrogen efficiency reached by the present system was 2.35%. Copyright © 2017 Elsevier B.V. All rights reserved.

Optimizing Regional Food and Energy Production under Limited Water Availability through Integrated Modeling

Directory of Open Access Journals (Sweden)

Junlian Gao

2018-05-01

Full Text Available Across the world, human activity is approaching planetary boundaries. In northwest China, in particular, the coal industry and agriculture are competing for key limited inputs of land and water. In this situation, the traditional approach to planning the development of each sector independently fails to deliver sustainable solutions, as solutions made in sectorial ‘silos’ are often suboptimal for the entire economy. We propose a spatially detailed cost-minimizing model for coal and agricultural production in a region under constraints on land and water availability. We apply the model to the case study of Shanxi province, China. We show how such an integrated optimization, which takes maximum advantage of the spatial heterogeneity in resource abundance, could help resolve the conflicts around the water–food–energy (WFE nexus and assist in its management. We quantify the production-possibility frontiers under different water-availability scenarios and demonstrate that in water-scarce regions, like Shanxi, the production capacity and corresponding production solutions are highly sensitive to water constraints. The shadow prices estimated in the model could be the basis for intelligent differentiated water pricing, not only to enable the water-resource transfer between agriculture and the coal industry, and across regions, but also to achieve cost-effective WFE management.

The forest products industry at an energy/climate crossroads

International Nuclear Information System (INIS)

Brown, Marilyn A.; Baek, Youngsun

2010-01-01

Transformational energy and climate policies are being debated worldwide that could have significant impact upon the future of the forest products industry. Because woody biomass can produce alternative transportation fuels, low-carbon electricity, and numerous other 'green' products in addition to traditional paper and lumber commodities, the future use of forest resources is highly uncertain. Using the National Energy Modeling System (NEMS), this paper assesses the future of the forest products industry under three possible U.S. policy scenarios: (1) a national renewable electricity standard, (2) a national policy of carbon constraints, and (3) incentives for industrial energy efficiency. In addition, we discuss how these policy scenarios might interface with the recently strengthened U.S. renewable fuels standards. The principal focus is on how forest products including residues might be utilized under different policy scenarios, and what such market shifts might mean for electricity and biomass prices, as well as energy consumption and carbon emissions. The results underscore the value of incentivizing energy efficiency in a portfolio of energy and climate policies in order to moderate electricity and biomass price escalation while strengthening energy security and reducing CO 2 emissions. - Research highlights: →Transformational energy and climate policies such as a national renewable electricity standard, a national policy of carbon constraints, and incentives for industrial energy efficiency could have significant impact upon the future of the forest products industry. →Each policy scenario reduces CO 2 emissions over time, compared to the business-as-usual forecast, with the carbon constrained policy producing the largest decline. As a package, the three policies together could cut CO 2 emissions from the electricity sector by an estimated 41% by 2030. →This study underscores the value of incentivizing energy efficiency in a portfolio of energy and

The power of design product innovation in sustainable energy technologies

CERN Document Server

Reinders, Angele H; Brezet, Han

2012-01-01

The Power of Design offers an introduction and a practical guide to product innovation, integrating the key topics that are necessary for the design of sustainable and energy-efficient products using sustainable energy technologies. Product innovation in sustainable energy technologies is an interdisciplinary field. In response to its growing importance and the need for an integrated view on the development of solutions, this text addresses the functional principles of various energy technologies next to the latest design processes and innovation methods. From the perspec

Energy expense by logistics within sugarcane's energy production chain : two case studies

International Nuclear Information System (INIS)

Romanelli, T.L.; Berruto, R.; Busato, P.; Neves, P.T.; Romanelli, L.L.

2010-01-01

As a renewable energy, biofuels are a viable alternative to fossil fuels. This study evaluated the energy expenditures of 2 case studies within the ethanol production chain in Brazil, notably ethanol for road transportation; and baled straw from mechanical harvesting of sugarcane, for electricity cogeneration. For ethanol road transportation, the 2 most commons tanker-trucks were evaluated. For the baled straw, prismatic and cylindrical bales were evaluated along with 3 types of raking. Although the largest vehicle for ethanol transportation consumed more fuel, it expended 12.42 per cent less energy per distance and transported mass. Proportionally, it had lower carbon dioxide emissions. The prismatic baled straw required 19.72 per cent less fuel due to the truck loading capacities of these bales. It was concluded that these results may prove useful when choosing alternatives within energy production systems.

Utilization of solar and nuclear energy for hydrogen production

International Nuclear Information System (INIS)

Fischer, M.

1987-01-01

Although the world-wide energy supply situation appears to have eased at present, non-fossil primary energy sources and hydrogen as a secondary energy carrier will have to take over a long-term and increasing portion of the energy supply system. The only non-fossil energy sources which are available in relevant quantities, are nuclear energy, solar energy and hydropower. The potential of H 2 for the extensive utilization of solar energy is of particular importance. Status, progress and development potential of the electrolytic H 2 production with photovoltaic generators, solar-thermal power plants and nuclear power plants are studied and discussed. The joint German-Saudi Arabian Research, Development and Demonstration Program HYSOLAR for the solar hydrogen production and utilization is summarized. (orig.)

Nuclear energy for hydrogen production

International Nuclear Information System (INIS)

Verfondern, K.

2007-01-01

In the long term, H 2 production technologies will be strongly focusing on CO 2 -neutral or CO 2 -free methods. Nuclear with its virtually no air-borne pollutants emissions appears to be an ideal option for large-scale centralized H 2 production. It will be driven by major factors such as production rates of fossil fuels, political decisions on greenhouse gas emissions, energy security and independence of foreign oil uncertainties, or the economics of large-scale hydrogen production and transmission. A nuclear reactor operated in the heat and power cogeneration mode must be located in close vicinity to the consumer's site, i.e., it must have a convincing safety concept of the combined nuclear/ chemical production plant. A near-term option of nuclear hydrogen production which is readily available is conventional low temperature electrolysis using cheap off-peak electricity from present nuclear power plants. This, however, is available only if the share of nuclear in power production is large. But as fossil fuel prices will increase, the use of nuclear outside base-load becomes more attractive. Nuclear steam reforming is another important near-term option for both the industrial and the transportation sector, since principal technologies were developed, with a saving potential of some 35 % of methane feedstock. Competitiveness will benefit from increasing cost level of natural gas. The HTGR heated steam reforming process which was simulated in pilot plants both in Germany and Japan, appears to be feasible for industrial application around 2015. A CO 2 emission free option is high temperature electrolysis which reduces the electricity needs up to about 30 % and could make use of high temperature heat and steam from an HTGR. With respect to thermochemical water splitting cycles, the processes which are receiving presently most attention are the sulfur-iodine, the Westinghouse hybrid, and the calcium-bromine (UT-3) cycles. Efficiencies of the S-I process are in the

Hydrogen Production from Nuclear Energy

Science.gov (United States)

Walters, Leon; Wade, Dave

2003-07-01

During the past decade the interest in hydrogen as transportation fuel has greatly escalated. This heighten interest is partly related to concerns surrounding local and regional air pollution from the combustion of fossil fuels along with carbon dioxide emissions adding to the enhanced greenhouse effect. More recently there has been a great sensitivity to the vulnerability of our oil supply. Thus, energy security and environmental concerns have driven the interest in hydrogen as the clean and secure alternative to fossil fuels. Remarkable advances in fuel-cell technology have made hydrogen fueled transportation a near-term possibility. However, copious quantities of hydrogen must be generated in a manner independent of fossil fuels if environmental benefits and energy security are to be achieved. The renewable technologies, wind, solar, and geothermal, although important contributors, simply do not comprise the energy density required to deliver enough hydrogen to displace much of the fossil transportation fuels. Nuclear energy is the only primary energy source that can generate enough hydrogen in an energy secure and environmentally benign fashion. Methods of production of hydrogen from nuclear energy, the relative cost of hydrogen, and possible transition schemes to a nuclear-hydrogen economy will be presented.

Low energy intense electron beams with extra-low energy spread

International Nuclear Information System (INIS)

Aleksandrov, A.V.; Calabrese, R.; Ciullo, G.; Dikansky, N.S.; Guidi, V.; Kot, N.C.; Kudelainen, V.I.; Lamanna, G.; Lebedev, V.A.; Logachov, P.V.; Tecchio, L.; Yang, B.

1994-01-01

Maximum achievable intensity for low energy electron beams is a feature that is not very often compatible with low energy spread. We show that a proper choice of the source and the acceleration optics allows one to match them together. In this scheme, a GaAs photocathode excited by a single-mode infrared laser and adiabatic acceleration in fully magnetised optics enables the production of a low-energy-spread electron beam with relatively high intensity. The technological problems associated with the method are discussed together with its limitations. (orig.)

A Theoretical Study of two Novel Concept Systems for Maximum Thermal-Chemical Conversion of Biomass to Hydrogen

Directory of Open Access Journals (Sweden)

Jacob N. Chung

2014-01-01

Full Text Available Two concept systems that are based on the thermochemical process of high-temperature steam gasification of lignocellulosic biomass and municipal solid waste are introduced. The primary objectives of the concept systems are 1 to develop the best scientific, engineering, and technology solutions for converting lignocellulosic biomass, as well as agricultural, forest and municipal waste to clean energy (pure hydrogen fuel, and 2 to minimize water consumption and detrimental impacts of energy production on the environment (air pollution and global warming. The production of superheated steam is by hydrogen combustion using recycled hydrogen produced in the first concept system while in the second concept system concentrated solar energy is used for the steam production. A membrane reactor that performs the hydrogen separation and water gas shift reaction is involved in both systems for producing more pure hydrogen and CO2 sequestration. Based on obtaining the maximum hydrogen production rate the hydrogen recycled ratio is around 20% for the hydrogen combustion steam heating system. Combined with pure hydrogen production, both high temperature steam gasification systems potentially possess more than 80% in first law overall system thermodynamic efficiencies.

A Theoretical Study of Two Novel Concept Systems for Maximum Thermal-Chemical Conversion of Biomass to Hydrogen

Energy Technology Data Exchange (ETDEWEB)

Chung, J. N., E-mail: jnchung@ufl.edu [Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, FL (United States)

2014-01-02

Two concept systems that are based on the thermochemical process of high temperature steam gasification of lignocellulosic biomass and municipal solid waste are introduced. The primary objectives of the concept systems are (1) to develop the best scientific, engineering, and technology solutions for converting lignocellulosic biomass, as well as agricultural, forest, and municipal waste to clean energy (pure hydrogen fuel), and (2) to minimize water consumption and detrimental impacts of energy production on the environment (air pollution and global warming). The production of superheated steam is by hydrogen combustion using recycled hydrogen produced in the first concept system while in the second concept system concentrated solar energy is used for the steam production. A membrane reactor that performs the hydrogen separation and water gas shift reaction is involved in both systems for producing more pure hydrogen and CO{sub 2} sequestration. Based on obtaining the maximum hydrogen production rate the hydrogen recycled ratio is around 20% for the hydrogen combustion steam heating system. Combined with pure hydrogen production, both high temperature steam gasification systems potentially possess more than 80% in first law overall system thermodynamic efficiencies.

Advertising, marketing and purchase behavior for energy-related products

Energy Technology Data Exchange (ETDEWEB)

Tiedemann, K.; Nelson, D.

1998-07-01

Energy conservation programs have relied heavily on incentives and regulatory standards to reduce residential energy consumption. However, in the changing market environment characterized by competitive pressures, alternative mechanisms such as marketing and promotions may increase substantially in importance compared to the demand-side management programs which have been the focus of most research. This paper describes the role of marketing and promotions in encouraging energy efficiency at the household level in British Columbia. The paper examines three related issues: first, the purchase process for energy-related products; second, the criteria used by customers in making purchase decisions; and third, the impact and effectiveness of alternative marketing tools. A key finding is the energy-related purchases do not fall into the impulse purchase category. There are two reasons for this: first, most of these products require installation and this requires a high level of commitment on the part of the purchaser; second, many energy-related products require a significant outlay of funds and this reduces impulse buying.

Improving energy productivity in paddy production through benchmarking-An application of data envelopment analysis

International Nuclear Information System (INIS)

Chauhan, Narvendra Singh; Mohapatra, Pratap K.J.; Pandey, Keshaw Prasad

2006-01-01

In this study, a data envelopment analysis approach has been used to determine the efficiencies of farmers with regard to energy use in rice production activities in the alluvial zone in the state of West Bengal in India. The study has helped to segregate efficient farmers from inefficient ones, identify wasteful uses of energy from different sources by inefficient farmers and to suggest reasonable savings in energy uses from different sources. The methods of cross efficiency matrix and distribution of virtual inputs are used to get insights into the performance of individual farmers, rank efficient farmers and identify the improved operating practices followed by a group of truly efficient farmers. The results reveal that, on an average, about 11.6% of the total input energy could be saved if the farmers follow the input package recommended by the study. The study also suggests that better use of power tillers and introduction of improved machinery would improve the efficiency of energy use and thereby improve the energy productivity of the rice production system in the zone

Improving energy productivity in paddy production through benchmarking-An application of data envelopment analysis

Energy Technology Data Exchange (ETDEWEB)

Chauhan, Narvendra Singh [Department of Agronomy, Uttar Banga Krishi Viswavidyalaya, P.O. Pundibari, District Cooch Behar (West Bengal) 736 165 (India)]. E-mail: nsc_01@rediffmail.com; Mohapatra, Pratap K.J. [Department of Industrial Engineering and Management, Indian Institute of Technology, Kharagpur (West Bengal) 721 302 (India); Pandey, Keshaw Prasad [Department of Agricultural and Food Engineering, Indian Institute of Technology, Kharagpur (West Bengal) 721 302 (India)

2006-06-15

In this study, a data envelopment analysis approach has been used to determine the efficiencies of farmers with regard to energy use in rice production activities in the alluvial zone in the state of West Bengal in India. The study has helped to segregate efficient farmers from inefficient ones, identify wasteful uses of energy from different sources by inefficient farmers and to suggest reasonable savings in energy uses from different sources. The methods of cross efficiency matrix and distribution of virtual inputs are used to get insights into the performance of individual farmers, rank efficient farmers and identify the improved operating practices followed by a group of truly efficient farmers. The results reveal that, on an average, about 11.6% of the total input energy could be saved if the farmers follow the input package recommended by the study. The study also suggests that better use of power tillers and introduction of improved machinery would improve the efficiency of energy use and thereby improve the energy productivity of the rice production system in the zone.

Short-time maximum entropy method analysis of molecular dynamics simulation: Unimolecular decomposition of formic acid

Science.gov (United States)

Takahashi, Osamu; Nomura, Tetsuo; Tabayashi, Kiyohiko; Yamasaki, Katsuyoshi

2008-07-01

We performed spectral analysis by using the maximum entropy method instead of the traditional Fourier transform technique to investigate the short-time behavior in molecular systems, such as the energy transfer between vibrational modes and chemical reactions. This procedure was applied to direct ab initio molecular dynamics calculations for the decomposition of formic acid. More reactive trajectories of dehydrolation than those of decarboxylation were obtained for Z-formic acid, which was consistent with the prediction of previous theoretical and experimental studies. Short-time maximum entropy method analyses were performed for typical reactive and non-reactive trajectories. Spectrograms of a reactive trajectory were obtained; these clearly showed the reactant, transient, and product regions, especially for the dehydrolation path.

MD simulations to evaluate effects of applied tensile strain on irradiation-induced defect production at various PKA energies

International Nuclear Information System (INIS)

Miyashiro, S.; Fujita, S.; Okita, T.; Okuda, H.

2012-01-01

Highlights: ► Strain effects on defect formation were evaluated at various PKA energies by MD. ► Radiation-induced defects were increased numerically by external strain. ► Enhanced formation of larger clusters causes the numerical increase of defects. ► Strain influence on the number of defects was greatest at about 20 keV PKA. ► Cluster size, which is mostly affected by strain, was greater with higher PKA energy. - Abstract: Molecular Dynamics (MD) simulations were conducted to investigate the influence of applied tensile strain on defect production during cascade damages at various Primary Knock-on Atom (PKA) energies of 1–30 keV. When 1% strain was applied, the number of surviving defects increased at PKA energies higher than 5 keV, although they did not increase at 1 keV. The rate of increase by strain application was higher with higher PKA energy, and attained the maximum at 20 keV PKA energy with a subsequent gradual decrease at 30 keV PKA energy The cluster size, mostly affected by strain, was larger with higher PKA energy, although clusters with fewer than seven interstitials did not increase in number at any PKA energy.

High energy photons production in nuclear reactions

International Nuclear Information System (INIS)

Nifenecker, H.; Pinston, J.A.

1990-01-01

Hard photon production, in nucleus-nucleus collisions, were studied at beam energies between 10 and 125 MeV. The main characteristics of the photon emission are deduced. They suggest that the neutron-proton collisions in the early stage of the reaction are the main source of high energy gamma-rays. An overview of the theoretical approaches is given and compared with experimental results. Theoretical attempts to include the contribution of charged pion exchange currents to photon production, in calculations of proton-nucleus-gamma and nucleus-nucleus-gamma reactions, showed suitable fitting with experimental data

Energy use in pig production: an examination of current Iowa systems.

Science.gov (United States)

Lammers, P J; Kenealy, M D; Kliebenstein, J B; Harmon, J D; Helmers, M J; Honeyman, M S

2012-03-01

This paper compares energy use for different pig production systems in Iowa, a leader in US swine production. Pig production systems include not only the growth and performance of the pigs, but also the supporting infrastructure of pig production. This supporting infrastructure includes swine housing, facility management, feedstuff provision, swine diets, and manure management. Six different facility type × diet formulation × cropping sequence scenarios were modeled and compared. The baseline system examined produces 15,600 pigs annually using confinement facilities and a corn-soybean cropping sequence. Diet formulations for the baseline system were corn-soybean meal diets that included the synthetic AA l-lysine and exogenous phytase. The baseline system represents the majority of current US pork production in the Upper Midwest, where most US swine are produced. This system was found to require 744.6 MJ per 136-kg market pig. An alternative system that uses bedded hoop barns for grow-finish pigs and gestating sows would require 3% less (720.8 MJ) energy per 136-kg market pig. When swine production systems were assessed, diet type and feed ingredient processing were the major influences on energy use, accounting for 61 and 79% of total energy in conventional and hoop barn-based systems, respectively. Improving feed efficiency and better matching the diet formulation with the thermal environment and genetic potential are thus key aspects of reducing energy use by pig production, particularly in a hoop barn-based system. The most energy-intensive aspect of provisioning pig feed is the production of synthetic N for crop production; thus, effectively recycling manure nutrients to cropland is another important avenue for future research. Almost 25% of energy use by a conventional farrow-to-finish pig production system is attributable to operation of the swine buildings. Developing strategies to minimize energy use for heating and ventilation of swine buildings while

Wind energy status in renewable electrical energy production in Turkey

International Nuclear Information System (INIS)

Kaygusuz, Kamil

2010-01-01

Main electrical energy sources of Turkey are thermal and hydraulic. Most of the thermal sources are derived from natural gas. Turkey imports natural gas; therefore, decreasing usage of natural gas is very important for both economical and environmental aspects. Because of disadvantages of fossil fuels, renewable energy sources are getting importance for sustainable energy development and environmental protection. Among the renewable sources, Turkey has very high wind energy potential. The estimated wind power capacity of Turkey is about 83,000 MW while only 10,000 MW of it seems to be economically feasible to use. Start 2009, the total installed wind power capacity of Turkey was only 4.3% of its total economical wind power potential (433 MW). However, the strong development of wind energy in Turkey is expected to continue in the coming years. In this study, Turkey's installed electric power capacity, electric energy production is investigated and also Turkey current wind energy status is examined. (author)

Evaluating Fenestration Products for Zero-Energy Buildings: Issuesfor Discussion

Energy Technology Data Exchange (ETDEWEB)

Arasteh, Dariush; Curcija, Charlie; Huang, Joe; Huizenga,Charlie; Kohler, Christian

2006-07-25

Computer modeling to determine fenestration product energy properties (U-factor, SHGC, VT) has emerged as the most cost-effective and accurate means to quantify them. Fenestration product simulation tools have been effective in increasing the use of low-e coatings and gas fills in insulating glass and in the widespread use of insulating frame designs and materials. However, for more efficient fenestration products (low heat loss products, dynamic products, products with non-specular optical characteristics, light re-directing products) to achieve widespread use, fenestration modeling software needs to be improved. This paper addresses the following questions: (1) Are the current properties (U, SHGC, VT) calculated sufficient to compare and distinguish between windows suitable for Zero Energy Buildings and conventional window products? If not, what data on the thermal and optical performance, on comfort, and on peak demand of windows is needed. (2) Are the algorithms in the tools sufficient to model the thermal and optical processes? Are specific heat transfer and optical effects not accounted for? Is the existing level of accuracy enough to distinguish between products designed for Zero Energy Buildings? Is the current input data adequate?

Energy sources consumption: end uses, efficiency and productivity

International Nuclear Information System (INIS)

Martin, J.M.

2005-01-01

This document analyzes the impact of the choices made by all actors, from the energy producers to the process and infrastructure designers and the end users, in the evolution of energy consumptions. Some very little improvements made in the energy efficiency of appliances can become equivalent to the production of several oil fields or power plants at the world scale. More efficient energy uses will not replace the additional productions but they must be considered together to be compared. The energy files are first analyzed as a whole in order to show the hidden field of energy choices. In this framework, users, designers and fitters have to face very different choices because they consider efficiency improvements under different aspects: scientifical, technical, economical and social (public information and habits). These differences in efficiency uses have a time and spatial impact on the growth of energy consumption. The economical and social factors influence the collective way to consume energy and are expressed by the energy intensity of the economic activity. The last part of this document analyzes the influence of this notion on the world energy consumption scenarios at the 2050 prospects. (J.S.)

Estimation of external costs of energy production in Finland

International Nuclear Information System (INIS)

Estlander, A.; Otterstroem, T.

1994-01-01

The goal of the project is to develop a method for estimation of external costs of energy production in Finland. The purpose of the method is to take into account all the most important impacts on health, materials and the environment. The study will assess environmental effects of emissions from Finnish energy production on people and the environment locally (population centres), nationally (Finland) and globally. The different energy production forms to be included in the study are heat and electric energy generated with coal, natural gas, fuel oil and peat (not industry's energy production). Local and national environmental impact assessment is carried out within the Finnish borders. The economic influence of emissions (in particular greenhouse gases) originating outside Finland but with global impact will also be assessed, as far as Finland is concerned. When studying the amounts of emissions the whole fuel chain is taken into account: production, processing or transport, storage in the different stages of the chain of use, and end use. The main components under review are SO 2 , NO x , CO 2 , H x C y , CO, particulates and a couple of heavy metals. In addition. the study considers ozone (O 3 ), which is formed in the atmosphere. The primary monetary valuation method used is the indirect monetarization. which is based on dose-response functions and the use of both market prices and willingness-to-pay assessments. The method to be developed during the project for monetary valuation of effects caused by emissions on health, materials and the environment can be utilized in further monetarization studies. The results of the work can used to assess the profitability of energy production plants and energy companies from the economic point of view

Energy production and storage inorganic chemical strategies for a warming world

CERN Document Server

Crabtree, Robert H

2013-01-01

Energy production and storage are central problems for our time. In principle, abundant energy is available from the sun to run the earth in a sustainable way. Solar energy can be directly harnessed by agricultural and photovoltaic means, but the sheer scale of the energy demand poses severe challenges, for example any major competition between biomass production and food production would simply transfer scarcity from energy to food. Indirect use of solar energy in the form of wind looks also promising, especially for those regions not blessed with abundant sunlight. Other modes such as tidal

Energy production study of crops with biofuel potential in Argentina

Energy Technology Data Exchange (ETDEWEB)

Donato, Lidia; Huerga, Ignacio; Hilbert, Jorge [Instituto Nacional de Tecnologia Agropecuaria (CIA/INTA), Buenos Aires (Argentina). Centro de Investigacion de Agroindustria. Inst. de Ingenieria Rural], Emails: ingdonato@cnia.inta.gov.ar, ihuerga@cnia.inta.gov.ar, hilbert@cnia.inta.gov.ar

2008-07-01

The present study is focus on the final energy balance of bioenergy production in Argentina using soybean, sunflower, rapeseed, corn and sorghum as feedstocks. The balance considers the difference between the energy contained per unit and the amount used for its generation in all the different steps from sowing to final destination. For direct energy consumption Costo Maq software was employed using local fuel consumption forecast for each field labor. Particular attention is paid to the energy consumption in the agricultural steps considering the distinctive no till system spread out in Argentina that has a very low energy input. Direct and indirect energy were considered in the different steps of bioethanol and biodiesel generation. Industrial conversion consumption was based on international literature data. Comparisons were made between tilled and no till practices and considering or not the energy contained in co products. Results indicate a balance ranging from 0.96 to 1.54 not considering the co products. If co products were introduced the balances ranged between 1.09 and 4.67. (author)

Process for production of a carbide by-product with microwave energy and aluminum by electrolysis

International Nuclear Information System (INIS)

Fuller, T.E.; Finell, L.R.

1985-01-01

Means and method for utilizing radiated electromagnetic energy to elevate at least one of two or more reactants to a temperature at which a chemical reaction will take place so as to provide a desired reaction product. In practice, at least one of reactants must be, or be made, susceptible to heating when radiated with electromagnetic energy. Electromagnetic energy source provides sufficient power to raise the temperature of said at least one reactant to cause that reactant to further raise the temperature of associated reactant materials making them further susceptible to heating under the influence of the impinging electromagnetic energy waves. The electromagnetic energy is provided at sufficient power to raise the temperature to the point at which reactants will react chemically to produce a desired reaction product. Since the heating action is localized, little or no energy is wasted in raising the wall temperatures of the reaction vessel in which the material is radiated. The use of a temperature sensitive sphincter output of reactor vessel provides means for recovering the desired chemical reaction product and for controlling the active time of microwave energy source and the injection of new reactant material when the product of the reaction is drawn off

Energy and materials flows in the production of olefins and their derivatives

Energy Technology Data Exchange (ETDEWEB)

Gaines, L.L.; Shen, S.Y.

1980-08-01

Production of olefins and their derivatives uses almost 3.5% of the oil and gas consumed annually in the United States. It is estimated that their production requires an input energy of 2 Q, which is 50% of the energy used in the production of all petrochemicals. Substantial amounts of this energy could be recovered through recycling. For example, recycling of a single plastic product, polyester soft drink bottles, could have recovered about 0.014 Q in 1979. (About 1.4 Q is used to produce plastic derivatives of olefins). Petrochemical processes use fuels as feedstocks, as well as for process energy, and a portion of this energy is not foregone and can be recovered through combustion of the products. The energy foregone in the production of ethylene is estimated to be 7800 Btu/lb. The energy foregone in plastics production ranges from 12,100 Btu/lb for the new linear low-density polyethylene to 77,200 Btu/lb for nylon 66, which is about 60% of the total energy input for that product. Further investigation of the following areas could yield both material and energy savings in the olefins industry: (1) recycling of petrochemical products to recover energy in addition to that recoverable through combustion, (2) impact of feedstock substitution on utilization of available national resources, and (3) effective use of the heat embodied in process steam. This steam accounts for a major fraction of the industry's energy input.

Report revision master: an energy analysis of consumer products packaging

Energy Technology Data Exchange (ETDEWEB)

1980-03-01

This report serves as a foundation for quantifying the potential for energy conservation in the Canadian consumer products packaging sector. Investigation was made of energy consumption, waste management, and energy conservation potential in the various stages of the packaging and consumption process: raw material acquisition, material and packaging manufacture, package filling and distribution, consumer use, post-consumption options (energy recovery, disposal, recycling), and cleaning and transportation (if applicable) between each stage. The food and beverage industry was singled out as the most important sector because of its large consumption of packaging. Significant opportunities for energy conservation were found, although any savings accomplished through packaging changes appear to be difficult to implement. Packaging energy savings seem to be able to be achieved only through a product-by-product, industry-by-industry initiative by means of product and package standardization. An efficient example of this is the milk distribution system, where refillable plastic jugs require only 1.4 MBtu per 3000 quarts delivered (as compared with, for example, 68.9 MBtu for disposable aluminium soft drink cans). Other conclusions are made concerning the optimization of packaging energy, with respect to types of packaging, energy requirements related to use of packaged products, impact of government policies and of retailing techiques, consumer lifestyles, and the like. 95 refs., 3 figs., 54 tabs.

Energy management in production: A novel method to develop key performance indicators for improving energy efficiency

International Nuclear Information System (INIS)

May, Gökan; Barletta, Ilaria; Stahl, Bojan; Taisch, Marco

2015-01-01

Highlights: • We propose a 7-step methodology to develop firm-tailored energy-related KPIs (e-KPIs). • We provide a practical guide for companies to identify their most important e-KPIs. • e-KPIs support identification of energy efficiency improvement areas in production. • The method employs an action plan for achieving energy saving targets. • The paper strengthens theoretical base for energy-based decision making in manufacturing. - Abstract: Measuring energy efficiency performance of equipments, processes and factories is the first step to effective energy management in production. Thus, enabled energy-related information allows the assessment of the progress of manufacturing companies toward their energy efficiency goals. In that respect, the study addresses this challenge where current industrial approaches lack the means and appropriate performance indicators to compare energy-use profiles of machines and processes, and for the comparison of their energy efficiency performance to that of competitors’. Focusing on this challenge, the main objective of the paper is to present a method which supports manufacturing companies in the development of energy-based performance indicators. For this purpose, we provide a 7-step method to develop production-tailored and energy-related key performance indicators (e-KPIs). These indicators allow the interpretation of cause-effect relationships and therefore support companies in their operative decision-making process. Consequently, the proposed method supports the identification of weaknesses and areas for energy efficiency improvements related to the management of production and operations. The study therefore aims to strengthen the theoretical base necessary to support energy-based decision making in manufacturing industries

Maximum Power Point Tracking in Variable Speed Wind Turbine Based on Permanent Magnet Synchronous Generator Using Maximum Torque Sliding Mode Control Strategy

Institute of Scientific and Technical Information of China (English)

Esmaeil Ghaderi; Hossein Tohidi; Behnam Khosrozadeh

2017-01-01

The present study was carried out in order to track the maximum power point in a variable speed turbine by minimizing electromechanical torque changes using a sliding mode control strategy.In this strategy,fhst,the rotor speed is set at an optimal point for different wind speeds.As a result of which,the tip speed ratio reaches an optimal point,mechanical power coefficient is maximized,and wind turbine produces its maximum power and mechanical torque.Then,the maximum mechanical torque is tracked using electromechanical torque.In this technique,tracking error integral of maximum mechanical torque,the error,and the derivative of error are used as state variables.During changes in wind speed,sliding mode control is designed to absorb the maximum energy from the wind and minimize the response time of maximum power point tracking (MPPT).In this method,the actual control input signal is formed from a second order integral operation of the original sliding mode control input signal.The result of the second order integral in this model includes control signal integrity,full chattering attenuation,and prevention from large fluctuations in the power generator output.The simulation results,calculated by using MATLAB/m-file software,have shown the effectiveness of the proposed control strategy for wind energy systems based on the permanent magnet synchronous generator (PMSG).

Hypernuclei, dibaryon and antinuclei production in high energy heavy ion collisions: Thermal production vs. coalescence

International Nuclear Information System (INIS)

Steinheimer, J.; Gudima, K.; Botvina, A.; Mishustin, I.; Bleicher, M.; Stöcker, H.

2012-01-01

We study the production of (hyper-)nuclei and dibaryons in most central heavy ion collisions at energies of E lab =1-160 A GeV. In particular we are interested in clusters produced from the hot and dense fireball. The formation rate of strange and non-strange clusters is estimated by assuming thermal production from the intermediate phase of the UrQMD-hydro hybrid model and alternatively by the coalescence mechanism from a hadronic cascade model. Both model types are compared in detail. For most energies we find that both approaches agree in their predictions for the yields of the clusters. Only for very low beam energies, and for dibaryons including Ξ's, we observe considerable differences. We also study the production of anti-matter clusters up to top RHIC energies and show that the observation of anti- 4 He and even anti- 4 Λ He is feasible. We have found a considerable qualitative difference in the energy dependence of the strangeness population factor R H when comparing the thermal production with the coalescence results.

Disaggregate energy consumption and industrial production in South Africa

International Nuclear Information System (INIS)

Ziramba, Emmanuel

2009-01-01

This paper tries to assess the relationship between disaggregate energy consumption and industrial output in South Africa by undertaking a cointegration analysis using annual data from 1980 to 2005. We also investigate the causal relationships between the various disaggregate forms of energy consumption and industrial production. Our results imply that industrial production and employment are long-run forcing variables for electricity consumption. Applying the [Toda, H.Y., Yamamoto, T., 1995. Statistical inference in vector autoregressions with possibly integrated processes. Journal of Econometrics 66, 225-250] technique to Granger-causality, we find bi-directional causality between oil consumption and industrial production. For the other forms of energy consumption, there is evidence in support of the energy neutrality hypothesis. There is also evidence of causality between employment and electricity consumption as well as coal consumption causing employment.

Higgs production as a probe of dark energy interactions

CERN Document Server

Brax, Philippe; Davis, Anne-Christine; Seery, David; Weltman, Amanda

2010-01-01

We study Higgs production under the influence of a light, scalar dark energy field with chameleon-like couplings to matter. Our analysis is relevant for hadron colliders, such as the Large Hadron Collider, which are expected to manufacture Higgs particles through weak boson fusion, or associated production with a Z or W. We show that the corrections arising in these models are too small to be observed. This result can be attributed to the gauge invariance of the low energy Lagrangian. As a by-product of our analysis, we provide the first microphysical realization of a dark energy model coupled to the electromagnetic field strength. In models where dark energy couples to all matter species in a uniform manner we are able to give a new, stringent bound on its coupling strength.

Higgs production as a probe of dark energy interactions

International Nuclear Information System (INIS)

Brax, Philippe; Davis, Anne-Christine; Seery, David

2009-11-01

We study Higgs production under the influence of a light, scalar dark energy field with chameleon-like couplings to matter. Our analysis is relevant for hadron colliders, such as the Large Hadron Collider, which are expected to manufacture Higgs particles through weak boson fusion, or associated production with a Z or W ± . We show that the corrections arising in these models are too small to be observed. This result can be attributed to the gauge invariance of the low energy Lagrangian. As a by-product of our analysis, we provide the first microphysical realization of a dark energy model coupled to the electromagnetic field strength. In models where dark energy couples to all matter species in a uniform manner we are able to give a new, stringent bound on its coupling strength. (orig.)

Higgs production as a probe of dark energy interactions

Energy Technology Data Exchange (ETDEWEB)

Brax, Philippe [CEA, IPhT, CNRS, URA2306, Gif-sur-Yvette (France). Inst. de Physique Theorique; Burrage, Clare [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Davis, Anne-Christine; Seery, David [Cambridge Univ. (United Kingdom). Dept. of Applied Mathematics and Theoretical Physics, Centre for Mathematical Sciences; Weltmann, Amanda [Cambridge Univ. (United Kingdom). Dept. of Applied Mathematics and Theoretical Physics, Centre for Mathematical Sciences; Cape Town Univ. (South Africa). Dept. of Mathematics and Applied Mathematics; Centre for Theoretical Cosmology Fellow, Cambridge (United Kingdom)

2009-11-15

We study Higgs production under the influence of a light, scalar dark energy field with chameleon-like couplings to matter. Our analysis is relevant for hadron colliders, such as the Large Hadron Collider, which are expected to manufacture Higgs particles through weak boson fusion, or associated production with a Z or W{sup {+-}}. We show that the corrections arising in these models are too small to be observed. This result can be attributed to the gauge invariance of the low energy Lagrangian. As a by-product of our analysis, we provide the first microphysical realization of a dark energy model coupled to the electromagnetic field strength. In models where dark energy couples to all matter species in a uniform manner we are able to give a new, stringent bound on its coupling strength. (orig.)

Mesonic atom production in high-energy nuclear collisions

International Nuclear Information System (INIS)

Wakai, M.; Bando, H.; Sano, M.

1987-08-01

The production probability of π-mesonic atom in high-energy nuclear collisions is estimated by a coalescence model. The production cross section is calculated for p + Ne and Ne + Ne systems at 2.1 GeV/A and 5.0 GeV/A beam energy. It is shown that nuclear fragments with larger charge numbers have the advantage in the formation of π-mesonic atoms. The cross section is proportional to Z 3 and of the order of magnitude of 1 ∼ 10 μb in all the above cases. The production cross sections of K-mesonic atoms are also estimated. (author)

Calendar Year 2009 Program Benefits for ENERGY STAR Labeled Products

Energy Technology Data Exchange (ETDEWEB)

Homan, Gregory K; Sanchez, Marla C.; Brown, Richard E.

2010-11-15

ENERGY STAR is a voluntary energy efficiency labeling program operated jointly by the Environmental Protection Agency (US EPA) and the U.S. Department of Energy (US DOE), designed to identify and promote energy-efficient products, buildings and practices. Since the program inception in 1992, ENERGY STAR has become a leading international brand for energy efficient products, and currently labels more than thirty products, spanning office equipment, heating, cooling and ventilation equipment, commercial and residential lighting, home electronics, and major appliances. ENERGY STAR's central role in the development of regional, national and international energy programs necessitates an open process whereby its program achievements to date as well as projected future savings are shared with stakeholders. This report presents savings estimates from the use ENERGY STAR labeled products. We present estimates of energy, dollar, and carbon savings achieved by the program in the year 2009, annual forecasts for 2010 and 2011, and cumulative savings estimates for the period 1993 through 2009 and cumulative forecasts for the period 2010 through 2015. Through 2009 the program saved 9.5 Quads of primary energy and avoided the equivalent of 170 million metric tons carbon (MMTC). The forecast for the period 2009-2015 is 11.5 Quads or primary energy saved and 202 MMTC emissions avoided. The sensitivity analysis bounds the best estimate of carbon avoided between 110 MMTC and 231 MMTC (1993 to 2009) and between 130 MMTC and 285 MMTC (2010 to 2015).

Innovative energy production in fusion reactors

International Nuclear Information System (INIS)

Iiyoshi, A.; Momota, H.; Motojima, O.

1994-01-01

Concepts of innovative energy production in neutron-lean fusion reactors without having the conventional turbine-type generator are proposed for improving the plant efficiency. These concepts are (a) traveling wave direct energy conversion of 14.7 MeV protons, (b) cusp type direct energy conversion of charged particles, (c) efficient use of radiation with semiconductor and supplying clean fuel in a form of hydrogen gas, and (d) direct energy conversion from deposited heat to electric power with semiconductor utilizing Nernst effect. The candidates of reactors such as a toroidal system and an open system are also studied for application of the new concepts. The study shows the above concepts for a commercial reactor are promising. (author)

Innovative energy production in fusion reactors

International Nuclear Information System (INIS)

Iiyoshi, A.; Momota, H.; Motojima, O.; Okamoto, M.; Sudo, S.; Tomita, Y.; Yamaguchi, S.; Ohnishi, M.; Onozuka, M.; Uenosono, C.

1993-10-01

Concepts of innovative energy production in neutron-lean fusion reactors without having the conventional turbine-type generator are proposed for improving the plant efficiency. These concepts are (a) traveling wave direct energy conversion of 14.7 MeV protons, (b) cusp type direct energy conversion of charged particles, (c) efficient use of radiation with semiconductor and supplying clean fuel in a form of hydrogen gas, and (d) direct energy conversion from deposited heat to electric power with semiconductor utilizing Nernst effect. The candidates of reactors such as a toroidal system and an open system are also studied for application of the new concepts. The study shows the above concepts for a commercial reactor are promising. (author)

Innovative energy production in fusion reactors

Science.gov (United States)

Iiyoshi, A.; Momota, H.; Motojima, O.; Okamoto, M.; Sudo, S.; Tomita, Y.; Yamaguchi, S.; Ohnishi, M.; Onozuka, M.; Uenosono, C.

1993-10-01

Concepts of innovative energy production in neutron-lean fusion reactors without having the conventional turbine-type generator are proposed for improving the plant efficiency. These concepts are: (1) traveling wave direct energy conversion of 14.7 MeV protons; (2) cusp type direct energy conversion of charged particles; (3) efficient use of radiation with semiconductor and supplying clean fuel in a form of hydrogen gas; and (4) direct energy conversion from deposited heat to electric power with semiconductor utilizing Nernst effect. The candidates of reactors such as a toroidal system and an open system are also studied for application of the new concepts. The study shows the above concepts for a commercial reactor are promising.

Innovative energy production in fusion reactors

Energy Technology Data Exchange (ETDEWEB)

Iiyoshi, A.; Momota, H.; Motojima, O.; Okamoto, M.; Sudo, S.; Tomita, Y.; Yamaguchi, S.; Ohnishi, M.; Onozuka, M.; Uenosono, C.

1993-10-01

Concepts of innovative energy production in neutron-lean fusion reactors without having the conventional turbine-type generator are proposed for improving the plant efficiency. These concepts are (a) traveling wave direct energy conversion of 14.7 MeV protons, (b) cusp type direct energy conversion of charged particles, (c) efficient use of radiation with semiconductor and supplying clean fuel in a form of hydrogen gas, and (d) direct energy conversion from deposited heat to electric power with semiconductor utilizing Nernst effect. The candidates of reactors such as a toroidal system and an open system are also studied for application of the new concepts. The study shows the above concepts for a commercial reactor are promising. (author).

The global contribution of energy consumption by product exports from China.

Science.gov (United States)

Tang, Erzi; Peng, Chong

2017-06-01

This paper presents a model to analyze the mechanism of the global contribution of energy usage by product exports. The theoretical analysis is based on the perspective that contribution estimates should be in relatively smaller sectors in which the production characteristics could be considered, such as the productivity distribution for each sector. Then, we constructed a method to measure the global contribution of energy usage. The simple method to estimate the global contribution is the percentage of goods export volume compared to the GDP as a multiple of total energy consumption, but this method underestimates the global contribution because it ignores the structure of energy consumption and product export in China. According to our measurement method and based on the theoretical analysis, we calculated the global contribution of energy consumption only by industrial manufactured product exports in a smaller sector per industry or manufacturing sector. The results indicated that approximately 42% of the total energy usage in the whole economy for China in 2013 was contributed to foreign regions. Along with the primary products and service export in China, the global contribution of energy consumption for China in 2013 by export was larger than 42% of the total energy usage.

Energy analysis of hydrogen and electricity production from aluminum-based processes

International Nuclear Information System (INIS)

Wang, Huizhi; Leung, Dennis Y.C.; Leung, Michael K.H.

2012-01-01

The aluminum energy conversion processes have been characterized to be carbon-free and sustainable. However, their applications are restrained by aluminum production capacity as aluminum is never found as a free metal on the earth. This study gives an assessment of typical aluminum-based energy processes in terms of overall energy efficiency and cost. Moreover, characteristics associated with different processes are identified. Results in this study indicate the route from which aluminum is produced can be a key factor in determining the efficiency and costs. Besides, the aluminum–air battery provides a more energy-efficient manner for the conversion of energy stored in primary aluminum and recovered aluminum from products compared to aluminum-based hydrogen production, whereas the aluminum-based hydrogen production gives a more energy-efficient way of utilizing energy stored in secondary aluminum or even scrap aluminum.

Energy production from marine biomass (Ulva lactuca)

Energy Technology Data Exchange (ETDEWEB)

Nikolaisen, L; Daugbjerg Jensen, P; Svane Bech, K [Danish Technological Institute (DTI), Taastrup (Denmark); and others

2011-11-15

In this project, methods for producing liquid, gaseous and solid biofuel from the marine macroalgae Ulva lactuca has been studied. To get an understanding of the growth conditions of Ulva lactuca, laboratory scale growth experiments describing N, P, and CO{sub 2} uptake and possible N{sub 2}O and CH{sub 4} production are carried out. The macroalgae have been converted to bioethanol and methane (biogas) in laboratory processes. Further the potential of using the algae as a solid combustible biofuel is studied. Harvest and conditioning procedures are described together with the potential of integrating macroalgae production at a power plant. The overall conclusions are: 1. Annual yield of Ulva lactuca is 4-5 times land-based energy crops. 2. Potential for increased growth rate when bubbling with flue gas is up to 20%. 3. Ethanol/butanol can be produced from pretreated Ulva of C6 and - for butanol - also C5 sugars. Fermentation inhibitors can possibly be removed by mechanical pressing. The ethanol production is 0,14 gram pr gram dry Ulva lactuca. The butanol production is lower. 4. Methane yields of Ulva are at a level between cow manure and energy crops. 5. Fast pyrolysis produces algae oil which contains 78 % of the energy content of the biomass. 6. Catalytic supercritical water gasification of Ulva lactuca is feasible and a methane rich gas can be obtained. 7. Thermal conversion of Ulva is possible with special equipment as low temperature gasification and grate firing. 8. Co-firing of Ulva with coal in power plants is limited due to high ash content. 9. Production of Ulva only for energy purposes at power plants is too costly. 10. N{sub 2}O emission has been observed in lab scale, but not in pilot scale production. 11. Analyses of ash from Ulva lactuca indicates it as a source for high value fertilizers. 12. Co-digestion of Ulva lactuca together with cattle manure did not alter the overall fertilization value of the digested cattle manure alone. (LN)

Maximum power point tracking

International Nuclear Information System (INIS)

Enslin, J.H.R.

1990-01-01

A well engineered renewable remote energy system, utilizing the principal of Maximum Power Point Tracking can be m ore cost effective, has a higher reliability and can improve the quality of life in remote areas. This paper reports that a high-efficient power electronic converter, for converting the output voltage of a solar panel, or wind generator, to the required DC battery bus voltage has been realized. The converter is controlled to track the maximum power point of the input source under varying input and output parameters. Maximum power point tracking for relative small systems is achieved by maximization of the output current in a battery charging regulator, using an optimized hill-climbing, inexpensive microprocessor based algorithm. Through practical field measurements it is shown that a minimum input source saving of 15% on 3-5 kWh/day systems can easily be achieved. A total cost saving of at least 10-15% on the capital cost of these systems are achievable for relative small rating Remote Area Power Supply systems. The advantages at larger temperature variations and larger power rated systems are much higher. Other advantages include optimal sizing and system monitor and control

Energy analysis of ethanol production from sweet sorghum

Energy Technology Data Exchange (ETDEWEB)

Worley, J.W. (Georgia Univ., Athens, GA (United States). Dept. of Agricultural Engineering); Vaughan, D.H.; Cundiff, J.S. (Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States). Dept. of Agricultural Engineering)

1992-01-01

The Piedmont System is a collection of equipment for efficiently removing the juice from sweet sorghum stalks for the production of ethanol. The concept is to separate the whole stalks into pith and rind-leaf fractions, pass only the pith fraction through a screw press, and thus achieve an improvement in juice-expression efficiency and press capacity. An energy analysis was done for two options of this proposed harvesting/processing system: (Option 1) The juice is evaporated to syrup and used throughout the year to produce ethanol, and the by-products are used as cattle feed. (Option 2) The juice is fermented as it is harvested, and the by-products (along with other cellulosic materials) are used as feedstock for the remainder of the year. Energy ratios (energy output/energy input) of 0.9, 1.1 and 0.8 were found for sweet sorghum Option 1, sweet sorghum Option 2, and corn, respectively, as feedstocks for ethanol. If only liquid fuels are considered, the ratios are increased to 3.5, 7.9 and 4.5. (author).

Buy Energy-Efficient Products: A Guide for Federal Purchasers and Specifiers

Energy Technology Data Exchange (ETDEWEB)

2016-07-01

In a single year, energy-efficient product purchases could save the federal government almost a half billion dollars worth of energy. By purchasing products that exceed the minimum required efficiency levels, buyers can save the government even more energy and money. Federal employees and contractors must take an active role in ensuring that the government receives products that meet efficiency requirements. This document provides an overview of product purchasing requirements and shows you how to write compliant contracts, find funding, and confirm product compliance.

Application of controlled thermonuclear reactor fusion energy for food production

International Nuclear Information System (INIS)

Dang, V.D.; Steinberg, M.

1975-06-01

Food and energy shortages in many parts of the world in the past two years raise an immediate need for the evaluation of energy input in food production. The present paper investigates systematically (1) the energy requirement for food production, and (2) the provision of controlled thermonuclear fusion energy for major energy intensive sectors of food manufacturing. Among all the items of energy input to the ''food industry,'' fertilizers, water for irrigation, food processing industries, such as beet sugar refinery and dough making and single cell protein manufacturing, have been chosen for study in detail. A controlled thermonuclear power reactor was used to provide electrical and thermal energy for all these processes. Conceptual design of the application of controlled thermonuclear power, water and air for methanol and ammonia synthesis and single cell protein production is presented. Economic analysis shows that these processes can be competitive. (auth)

Production of Energy Efficient Preform Structures (PEEPS)

Energy Technology Data Exchange (ETDEWEB)

Dr. John A. Baumann

2012-06-08

Due to its low density, good structural characteristics, excellent fabrication properties, and attractive appearance, aluminum metal and its alloys continue to be widely utilized. The transportation industry continues to be the largest consumer of aluminum products, with aerospace as the principal driver for this use. Boeing has long been the largest single company consumer of heat-treated aluminum in the U.S. The extensive use of aluminum to build aircraft and launch vehicles has been sustained, despite the growing reliance on more structurally efficient carbon fiber reinforced composite materials. The trend in the aerospace industry over the past several decades has been to rely extensively on large, complex, thin-walled, monolithic machined structural components, which are fabricated from heavy billets and thick plate using high speed machining. The use of these high buy-to-fly ratio starting product forms, while currently cost effective, is energy inefficient, with a high environmental impact. The widespread implementation of Solid State Joining (SSJ) technologies, to produce lower buy-to-fly ratio starting forms, tailored to each specific application, offers the potential for a more sustainable manufacturing strategy, which would consume less energy, require less material, and reduce material and manufacturing costs. One objective of this project was to project the energy benefits of using SSJ techniques to produce high-performance aluminum structures if implemented in the production of the world fleet of commercial aircraft. A further objective was to produce an energy consumption prediction model, capable of calculating the total energy consumption, solid waste burden, acidification potential, and CO2 burden in producing a starting product form - whether by conventional or SSJ processes - and machining that to a final part configuration. The model needed to be capable of computing and comparing, on an individual part/geometry basis, multiple possible

The energy balance of utilising meadow grass in Danish biogas production

DEFF Research Database (Denmark)

Meyer, Ane Katharina Paarup; Raju, Chitra Sangaraju; Kucheryavskiy, Sergey V.

2015-01-01

of meadow areas, different relevant geo-datasets, spatial analyses, and various statistical analyses. The results show that values for the energy return on energy invested (EROEI) ranging from 1.7 to 3.3 can be obtained when utilising meadow grasses in local biogas production. The total national net energy......This paper presents a study of the energy balance of utilising nature conservation biomass from meadow habitats in Danish biogas production. Utilisation of nature conservation grass in biogas production in Denmark represents an interesting perspective for enhancing nature conservation of the open...... grassland habitats, while introducing an alternative to the use of intensively cultivated energy crops as co-substrates in manure based biogas plants. The energy balance of utilising nature conservation grass was investigated by using: data collected from previous investigations on the productivity...

Energy use pattern in production agriculture of a typical village in arid zone - Part III

International Nuclear Information System (INIS)

Singh, H.; Mishra, D.; Nahar, N.M.

2004-01-01

India has 31.71 Mha of hot arid areas, of which 61.8% is in Western Rajasthan, commonly known as the 'Thar Desert'. A detailed study of the energy use pattern in production agriculture for a representative village, Pemasar, district Bikaner of zone II (200 mm/yr ≤ annual rainfall < 300 mm/yr) has been conducted. Out of the total geographical area (945.7 ha) of the village, 693.6 ha is cultivable land. The main crops grown in the village are cluster bean, moth bean, groundnut, green gram (Kharif), wheat, mustard, gram, barley and rocket salad (Rabi). In general, Kharif crops are grown as rain fed crops, but due to low rainfall in the zone and the presence of the Indira Gandhi Canal, even Kharif crops are raised under irrigated conditions. However, the area covered under irrigation is meagre as the availability of canal water is very much limited and uncertain. Operation wise, the total energy consumed for rain fed Kharif crops is minimum (1187.6 MJ/ha) for moth bean and maximum (1261.9 MJ/ha) for cluster bean, while for irrigated crops, it is minimum (2847.3 MJ/ha) for moth bean, and maximum (12,809.6 MJ/ha) for groundnut. The average specific energy for cultivation of cluster bean (rain fed), cluster bean (irrigated), moth bean (rain fed), moth bean (irrigated) and groundnut were 11.7, 7.5, 7.7, 7.4 and 11.2 MJ/ha, respectively. Operation wise, the energy consumed for Rabi crops is minimum (3855.6 MJ/ha) for rocket salad followed by 4779.4 MJ/ha for mustard, 4845.2 MJ/ha for gram and maximum (7953.2 MJ/ha) for wheat. The average specific energy for cultivation of wheat, gram, mustard and rocket salad were 11.4, 16.5, 13.2 and 13.7 MJ/ha, respectively. The average values of estimated energy ratio for cluster bean (rain fed), cluster bean (irrigated), moth bean (rain fed), moth bean (irrigated) and groundnut were 2.1, 0.5, 3.4, 3.5 and 3.0, respectively. This suggests that the moth bean crop is more remunerating to the farmers in Kharif as compared to cluster bean

Energy use pattern in production agriculture of a typical village in arid zone - Part III

Energy Technology Data Exchange (ETDEWEB)

Singh, H. E-mail: hsingh11@rediffmail.com; Mishra, D.; Nahar, N.M

2004-09-01

India has 31.71 Mha of hot arid areas, of which 61.8% is in Western Rajasthan, commonly known as the 'Thar Desert'. A detailed study of the energy use pattern in production agriculture for a representative village, Pemasar, district Bikaner of zone II (200 mm/yr {<=} annual rainfall < 300 mm/yr) has been conducted. Out of the total geographical area (945.7 ha) of the village, 693.6 ha is cultivable land. The main crops grown in the village are cluster bean, moth bean, groundnut, green gram (Kharif), wheat, mustard, gram, barley and rocket salad (Rabi). In general, Kharif crops are grown as rain fed crops, but due to low rainfall in the zone and the presence of the Indira Gandhi Canal, even Kharif crops are raised under irrigated conditions. However, the area covered under irrigation is meagre as the availability of canal water is very much limited and uncertain. Operation wise, the total energy consumed for rain fed Kharif crops is minimum (1187.6 MJ/ha) for moth bean and maximum (1261.9 MJ/ha) for cluster bean, while for irrigated crops, it is minimum (2847.3 MJ/ha) for moth bean, and maximum (12,809.6 MJ/ha) for groundnut. The average specific energy for cultivation of cluster bean (rain fed), cluster bean (irrigated), moth bean (rain fed), moth bean (irrigated) and groundnut were 11.7, 7.5, 7.7, 7.4 and 11.2 MJ/ha, respectively. Operation wise, the energy consumed for Rabi crops is minimum (3855.6 MJ/ha) for rocket salad followed by 4779.4 MJ/ha for mustard, 4845.2 MJ/ha for gram and maximum (7953.2 MJ/ha) for wheat. The average specific energy for cultivation of wheat, gram, mustard and rocket salad were 11.4, 16.5, 13.2 and 13.7 MJ/ha, respectively. The average values of estimated energy ratio for cluster bean (rain fed), cluster bean (irrigated), moth bean (rain fed), moth bean (irrigated) and groundnut were 2.1, 0.5, 3.4, 3.5 and 3.0, respectively. This suggests that the moth bean crop is more remunerating to the farmers in Kharif as compared to

Economic competitiveness of electricity production means inside smart grids: application to nuclear energy and variable renewable energies

International Nuclear Information System (INIS)

Keppler, J.H.; Baritaud, M.; Berthelemy, M.

2017-01-01

For a long time the comparison of the production costs of electricity from various primary sources were made on the basis of levelised costs of electricity (LCOE). LCOE is in fact the cost of the technology used for the production. In recent years solar and wind energies have seen their LCOE drop sharply (-60 % for solar power in 5 years) while nuclear energy's LCOE is now stabilized. In order to assess the cost of renewable energies, LCOE are not sufficient because variable energies like solar or wind power require other means of production to compensate their variability. Another point is that renewable energies are decentralized and as a consequence require investments to develop the power distribution system. This analysis presents a new methodology to compare the costs of electricity production means. This methodology takes into account LCOE and a system cost that represents the cost of the effects of the technology on the rest of the electricity production system. (A.C.)

Energy management for cost reduction in the production. TEEM - Total Energy Efficiency Management; Energiemanagement zur Kostensenkung in der Produktion. TEEM - Total Energy Efficiency Management

Energy Technology Data Exchange (ETDEWEB)

Westkaemper, Engelbert; Verl, Alexander (eds.)

2009-07-01

Within the workshop of the Fraunhofer Institute for Manufacturing Engineering and Automation IPA (Stuttgart, Federal Republic of Germany) at 6th October, 2009, in Stuttgart the following lectures were held: (1) Presentation of Fraunhofer Institute for Manufacturing Engineering and Automation IPA (Engelbert Westkaemper); (2) TEEM - Total Energy Efficiency Management - ''With energy management to an energy efficient production'' (Alexander Schloske); (3) DIN EN 16001 Introduction of an energy management system - utilization and advantages for companies (Sylvia Wahren); (4) Analysis of the energy efficiency with power flow - Support and implementation at factory planning and optimization of production (Klaus Erlach); (5) Total Energy Efficiency Management - Approaches at the company Kaercher in injection moulding for example (Axel Leschtar); (6) Modelling the embodied product energy (Shahin Rahimifard); (7) Acquisition of energy data in the production - Technologies and possibilities (Joachim Neher); (8) Active energy management by means of an ''energy control centre'' - Analysis of the real situation and upgrading measures in the production using coating plants as an example (Wolfgang Klein); (9) Visualisation and simulation of energy values in the digital factory (Carmen Constantinescu, Axel Bruns).

Disaggregate energy consumption and industrial production in South Africa

Energy Technology Data Exchange (ETDEWEB)

Ziramba, Emmanuel [Department of Economics, University of South Africa, P.O Box 392, UNISA 0003 (South Africa)

2009-06-15

This paper tries to assess the relationship between disaggregate energy consumption and industrial output in South Africa by undertaking a cointegration analysis using annual data from 1980 to 2005. We also investigate the causal relationships between the various disaggregate forms of energy consumption and industrial production. Our results imply that industrial production and employment are long-run forcing variables for electricity consumption. Applying the [Toda, H.Y., Yamamoto, T., 1995. Statistical inference in vector autoregressions with possibly integrated processes. Journal of Econometrics 66, 225-250] technique to Granger-causality, we find bi-directional causality between oil consumption and industrial production. For the other forms of energy consumption, there is evidence in support of the energy neutrality hypothesis. There is also evidence of causality between employment and electricity consumption as well as coal consumption causing employment. (author)

Initial study - compilation and synthesis of knowledge about energy crops from field to energy production

Energy Technology Data Exchange (ETDEWEB)

Berg, Magnus; Bubholz, Monika; Forsberg, Maya; Myringer, Aase; Palm, Ola; Roennbaeck, Marie; Tullin, Claes

2007-11-15

Energy crops constitute an yet not fully utilised potential as fuel for heating and power production. As competition for biomass increases interest in agricultural fuels such as straw, energy grain, willow, reed canary grass and hemp is increasing. Exploiting the potential for energy crops as fuels will demand that cultivation and harvest be coordinated with transportation, storage and combustion of the crops. Together, Vaermeforsk and the Swedish Farmers' Foundation for Agricultural Research (SLF), have taken the initiative to a common research programme. The long-term aim of the programme is to increase production and utilisation of bioenergy from agriculture to combustion for heat and power production in Sweden. The vision is that during the course of the 2006 - 2009 programme, decisive steps will be taken towards a functioning market for biofuels for bioenergy from agriculture. This survey has compiled and synthesised available knowledge and experiences about energy crops from field to energy production. The aim has been to provide a snapshot of knowledge today, to identify knowledge gaps and to synthesise knowledge we have today into future research needs. A research plan proposal has been developed for the research programme

Deep Geothermal Energy Production in Germany

Directory of Open Access Journals (Sweden)

Thorsten Agemar

2014-07-01

Full Text Available Germany uses its low enthalpy hydrothermal resources predominantly for balneological applications, space and district heating, but also for power production. The German Federal government supports the development of geothermal energy in terms of project funding, market incentives and credit offers, as well as a feed-in tariff for geothermal electricity. Although new projects for district heating take on average six years, geothermal energy utilisation is growing rapidly, especially in southern Germany. From 2003 to 2013, the annual production of geothermal district heating stations increased from 60 GWh to 530 GWh. In the same time, the annual power production increased from 0 GWh to 36 GWh. Currently, almost 200 geothermal facilities are in operation or under construction in Germany. A feasibility study including detailed geological site assessment is still essential when planning a new geothermal facility. As part of this assessment, a lot of geological data, hydraulic data, and subsurface temperatures can be retrieved from the geothermal information system GeotIS, which can be accessed online [1].

Oil sand synfuel production using nuclear energy

International Nuclear Information System (INIS)

Barnert, H.

1984-10-01

The importance of oil sand as a primary energy carrier is illustrated. The oil sand mining project 'synfuel' in Fort McMurray, Alberta, Canada, is described. On the basis of a layout of an In-situ-process different possibilities of introducing nuclear energy to the process are described. This leads to an increase of the product yield, leading finally to a doubling of the energy output compared to the reference layout. The introduction of nuclear energy contributes to the reduction of emissions, in particular to the emission of carbon dioxide in the conversion process. (orig.)

Energy inputs and greenhouse gases emissions in wheat production in Gorgan, Iran

International Nuclear Information System (INIS)

Soltani, Afshin; Rajabi, M.H.; Zeinali, E.; Soltani, Elias

2013-01-01

The objectives of this study were to analyze energy use and greenhouse gases (GHG) emissions in various wheat production scenarios in north eastern Iran and to identify measures to reduce energy use and GHG emissions. Three high-input, a low-input, a better crop management and a usual production scenarios were included. All activities and production processes were monitored and recorded. Averages of total energy input and output were 15.58 and 94.4 GJ ha −1 , respectively. Average across scenarios, GHG emissions of 1137 kg CO 2 -eq ha −1 and 291 kg CO 2 -eq t −1 were estimated. The key factors relating to energy use and GHG emissions were seedbed preparation and sowing and applications of nitrogen fertilizer. The better crop management production scenario required 38% lower nitrogen fertilizer (and 33% lower total fertilizer), consumed 11% less input energy and resulted in 33% more grain yield and output energy compared to the usual production scenario. It also resulted in 20% less GHG emissions per unit field area and 40% less GHG emissions per ton of grain. It was concluded that this scenario was the cleaner production scenario in terms of energy use and GHG emissions. Measures of improvement in energy use and GHG emission were identified. - Highlights: ► Wheat production scenarios were evaluated for energy use and greenhouse gases emission. ► A better crop management production scenario was the cleaner production scenario. ► Measures to reduce energy use and greenhouse gases emission were identified

Maruhn-Greiner Maximum of Uranium Fission for Confirmation of Low Energy Nuclear Reactions LENR via a Compound Nucleus with Double Magic Numbers

Science.gov (United States)

Hora, H.; Miley, G. H.

2007-12-01

One of the most convincing facts about LENR due to deuterons of very high concentration in host metals as palladium is the measurement of the large scale minimum of the reaction probability depending on the nucleon number A of generated elements at A = 153 where a local maximum was measured. This is similar to the fission of uranium at A = 119 where the local maximum follows from the Maruhn-Greiner theory if the splitting nuclei are excited to about MeV energy. The LENR generated elements can be documented any time after the reaction by SIMS or K-shell X-ray excitation to show the very unique distribution with the local maximum. An explanation is based on the strong Debye screening of the Maxwellian deuterons within the degenerate rigid electron background especially within the swimming electron layer at the metal surface or at interfaces. The deuterons behave like neutrals at distances of about 2 picometers. They may form clusters due to soft attraction in the range above thermal energy. Clusters of 10 pm diameter may react over long time probabilities (megaseconds) with Pd nuclei leading to a double magic number compound nucleus which splits like in fission to the A = 153 element distribution.

Utilization of geothermal energy for drying fish products

International Nuclear Information System (INIS)

Arason, S.; Arnason, H.

1992-01-01

This paper is about industrial uses of geothermal energy for drying of fish products. Drying is an ancient method for preservation of foods, the main purpose of which is to increase the preservation time. For drying, an external source of energy is needed to extract water. In this paper an emphasis is placed on drying fish and associated processes, and how geothermal energy can be used to substitute oil or electricity. The Icelandic Fisheries Laboratories have been experimenting with different methods of drying, and several drying stations have been designed for indoor drying of fish products. Today there are more than a dozen companies in this country which are drying fish indoors using for that purpose electricity and/or geothermal energy. Further possibilities are available when fish processing plants are located in geothermal areas

Meson production in two-photon interactions at LHC energies

Energy Technology Data Exchange (ETDEWEB)

Da Silva, D. T.; Goncalves, V. P.; Sauter, W. K. [Instituto de Fisica e Matematica, Universidade Federal de Pelotas, Campus Universitario UFPel, CP 354, 96010-900, Capao do Leao-RS (Brazil)

2013-03-25

The LHC opens a new kinematical regime at high energy, where several questions related to the description of the high-energy regime of the Quantum Chromodynamics (QCD) remain without satisfactory answers. Some open questions are the search for non-q-bar q resonances, the determination of the spectrum of q-bar q states and the identification of states with anomalous {gamma}{gamma} couplings. A possible way to study these problems is the study of meson production in two-photon interactions. In this contribution we calculate the meson production in two-photon interactions at LHC energies considering proton - proton collisions and estimate the total cross section for the production of the mesons {pi}, a, f, {eta} and {chi}.

Investigation of energy inputs for peach production using sensitivity analysis in Iran

International Nuclear Information System (INIS)

Royan, Mahsa; Khojastehpour, Mehdi; Emadi, Bagher; Mobtaker, Hassan Ghasemi

2012-01-01

Highlights: ► We investigated energy use and inputs–output relationship in peach production. ► Total energy consumption in peach production was 37536.96 MJ ha −1 . ► Diesel fuel with about (26.32%) was the major energy consumer. ► Energy use efficiency and energy productivity were 0.55 and 0.29 kg MJ −1 . ► The machinery energy was the most significant input affecting the output level. - Abstract: The purpose of this research was to investigate the energy balance between the energy inputs and yield in peach production in Golestan province of Iran as a case study. The results showed that total energy consumption in peach production was 37536.96 MJ ha −1 where the diesel fuel with about (26.32%) was the major energy consumer. The direct energy shared about (50.98%) whereas the indirect energy did (49.02%). Energy use efficiency, energy productivity, specific energy and net energy were 0.55, 0.29 kg MJ −1 , 3.41 MJ kg −1 and −16642.03 MJ ha −1 , respectively. Econometric assessment results revealed that the energy inputs of human labor, machinery, diesel fuel, chemical fertilizers and farm yard manure had significant influence on the yield. The impact of human labor energy (1.36) was found as the highest among the other input parameters. Sensitivity analysis indicated that the MPP value of energy inputs was between −2.8 and 11.31. Also the MPP value of human labor was the highest, followed by diesel fuel and farm yard manure energy inputs, respectively.