Paul Scherrer Institute Scientific Report 1998. Volume V: General Energy

Energy Technology Data Exchange (ETDEWEB)

Daum, C; Leuenberger, J [eds.

1999-08-01

In view of its mission to contribute towards the development of a globally more sustainable energy supply system, the General Energy Department is focusing on four topical areas: advancing technologies for the use of renewable energies; investigating options for chemical and electrochemical energy storage on various time scales; developing highly efficient converters for the low emission use of fossil and renewable fuels, including both combustion devices and fuel cells; analyzing the consequences of energy use, and advancing scenarios for the development of the energy supply system. Progress in 1998 in these topical areas is described in this report. A list of scientific publications in 1998 is also provided. (author) figs., tabs., refs.

Chinese hotel general managers' perspectives on energy-saving practices

Science.gov (United States)

Zhu, Yidan

As hotels' concern about sustainability and budget-control is growing steadily, energy-saving issues have become one of the important management concerns hospitality industry face. By executing proper energy-saving practices, previous scholars believed that hotel operation costs can decrease dramatically. Moreover, they believed that conducting energy-saving practices may eventually help the hotel to gain other benefits such as an improved reputation and stronger competitive advantage. The energy-saving issue also has become a critical management problem for the hotel industry in China. Previous research has not investigated energy-saving in China's hotel segment. To achieve a better understanding of the importance of energy-saving, this document attempts to present some insights into China's energy-saving practices in the tourist accommodations sector. Results of the study show the Chinese general managers' attitudes toward energy-saving issues and the differences among the diverse hotel managers who responded to the study. Study results indicate that in China, most of the hotels' energy bills decrease due to the implementation of energy-saving equipments. General managers of hotels in operation for a shorter period of time are typically responsible for making decisions about energy-saving issues; older hotels are used to choosing corporate level concerning to this issue. Larger Chinese hotels generally have official energy-saving usage training sessions for employees, but smaller Chinese hotels sometimes overlook the importance of employee training. The study also found that for the Chinese hospitality industry, energy-saving practices related to electricity are the most efficient and common way to save energy, but older hotels also should pay attention to other ways of saving energy such as water conservation or heating/cooling system.

General Business Model Patterns for Local Energy Management Concepts

International Nuclear Information System (INIS)

Facchinetti, Emanuele; Sulzer, Sabine

2016-01-01

The transition toward a more sustainable global energy system, significantly relying on renewable energies and decentralized energy systems, requires a deep reorganization of the energy sector. The way how energy services are generated, delivered, and traded is expected to be very different in the coming years. Business model innovation is recognized as a key driver for the successful implementation of the energy turnaround. This work contributes to this topic by introducing a heuristic methodology easing the identification of general business model patterns best suited for Local Energy Management concepts such as Energy Hubs. A conceptual framework characterizing the Local Energy Management business model solution space is developed. Three reference business model patterns providing orientation across the defined solution space are identified, analyzed, and compared. Through a market review, a number of successfully implemented innovative business models have been analyzed and allocated within the defined solution space. The outcomes of this work offer to potential stakeholders a starting point and guidelines for the business model innovation process, as well as insights for policy makers on challenges and opportunities related to Local Energy Management concepts.

General Business Model Patterns for Local Energy Management Concepts

Energy Technology Data Exchange (ETDEWEB)

Facchinetti, Emanuele, E-mail: emanuele.facchinetti@hslu.ch; Sulzer, Sabine [Lucerne Competence Center for Energy Research, Lucerne University of Applied Science and Arts, Horw (Switzerland)

2016-03-03

The transition toward a more sustainable global energy system, significantly relying on renewable energies and decentralized energy systems, requires a deep reorganization of the energy sector. The way how energy services are generated, delivered, and traded is expected to be very different in the coming years. Business model innovation is recognized as a key driver for the successful implementation of the energy turnaround. This work contributes to this topic by introducing a heuristic methodology easing the identification of general business model patterns best suited for Local Energy Management concepts such as Energy Hubs. A conceptual framework characterizing the Local Energy Management business model solution space is developed. Three reference business model patterns providing orientation across the defined solution space are identified, analyzed, and compared. Through a market review, a number of successfully implemented innovative business models have been analyzed and allocated within the defined solution space. The outcomes of this work offer to potential stakeholders a starting point and guidelines for the business model innovation process, as well as insights for policy makers on challenges and opportunities related to Local Energy Management concepts.

Energy Usage Analysis System

Data.gov (United States)

General Services Administration — The EUAS application is a web based system which serves Energy Center of Expertise, under the Office of Facilitates Management and Service Programs. EUAS is used for...

Energy Hub’s Structural and Operational Optimization for Minimal Energy Usage Costs in Energy Systems

Directory of Open Access Journals (Sweden)

Thanh Tung Ha

2018-03-01

Full Text Available The structural and optimal operation of an Energy Hub (EH has a tremendous influence on the hub’s performance and reliability. This paper envisions an innovative methodology that prominently increases the synergy between structural and operational optimization and targets system cost affordability. The generalized energy system structure is presented theoretically with all selective hub sub-modules, including electric heater (EHe and solar sources block sub-modules. To minimize energy usage cost, an energy hub is proposed that consists of 12 kinds of elements (i.e., energy resources, conversion, and storage functions and is modeled mathematically in a General Algebraic Modeling System (GAMS, which indicates the optimal hub structure’s corresponding elements with binary variables (0, 1. Simulation results contrast with 144 various scenarios established in all 144 categories of hub structures, in which for each scenario the corresponding optimal operation cost is previously calculated. These case studies demonstrate the effectiveness of the suggested model and methodology. Finally, avenues for future research are also prospected.

Evolving energy systems

Energy Technology Data Exchange (ETDEWEB)

Mills, E.

1991-04-01

This thesis presents scenarios of future energy systems, a cost-benefit analysis of measures to avoid greenhouse-gas emissions, an analysis of the effect of energy prices on end-use efficiencies and fuel choices, and an evaluation of financial-incentive programs designed to induce investments in efficient energy use. Twelve integrated energy supply/demand scenarios for the Swedish heat-and-power sector are presented to illustrate the potential for improvements in end-use efficiency and increased utilization of renewable energy sources. The results show that greenhouse-gas emissions could be reduced by 35 per cent from 1987 levels by 2010, with a net economic benefit compared to a business-as-usual scenario. A generalized methodology for calculating the net costs of reducing greenhouse-gas emissions is applied to a variety of fuel choices and energy end-use technologies. A key finding is that a combination of increased end-use efficiencies and use of renewable energy systems is required to achieve maximum cost-effective emissions reductions. End-use efficiencies and inter-fuel competition in Denmark and Sweden are compared during a time period in which real electricity prices were declining in Sweden and increasing in Denmark. Despite these different price environments, efficiencies and choices of heating fuels did not generally develop as expected according to economic theory. The influences of counter-price and non-price factors are important in understanding this outcome. Relying on prices alone injects considerable uncertainty into the energy planning process, and precludes efficiency improvements and fuel choices attainable with other mechanisms. Incentive programs can be used to promote energy-efficient technologies. Utilities in Europe have recently offered financial incentives intended to stimulate the adoption of compact-fluorescent lamps. These programs have been cost-effective in comparison to new electric supply. (au).

Hamiltonian Dynamics and Positive Energy in General Relativity

Energy Technology Data Exchange (ETDEWEB)

Deser, S. [Physics Department, Brandeis University, Waltham, MA (United States)

1969-07-15

A review is first given of the Hamiltonian formulation of general relativity; the gravitational field is a self-interacting massless spin-two system within the framework of ordinary Lorentz covariant field theory. The recently solved problem of positive-definiteness of the field energy is then discussed. The latter, a conserved functional of the dynamical variables, is shown to have only one extremum, a local minimum, which is the vacuum state (flat space). This implies positive energy for the field, with the vacuum as ground-state. Similar results hold when minimally coupled matter is present. (author)

Distributed energy systems with wind power and energy storage

Energy Technology Data Exchange (ETDEWEB)

Korpaas, Magnus

2004-07-01

The topic of this thesis is the study of energy storage systems operating with wind power plants. The motivation for applying energy storage in this context is that wind power generation is intermittent and generally difficult to predict, and that good wind energy resources are often found in areas with limited grid capacity. Moreover, energy storage in the form of hydrogen makes it possible to provide clean fuel for transportation. The aim of this work has been to evaluate how local energy storage systems should be designed and operated in order to increase the penetration and value of wind power in the power system. Optimization models and sequential and probabilistic simulation models have been developed for this purpose. Chapter 3 presents a sequential simulation model of a general wind hydrogen energy system. Electrolytic hydrogen is used either as a fuel for transportation or for power generation in a stationary fuel cell. The model is useful for evaluating how hydrogen storage can increase the penetration of wind power in areas with limited or no transmission capacity to the main grid. The simulation model is combined with a cost model in order to study how component sizing and choice of operation strategy influence the performance and economics of the wind-hydrogen system. If the stored hydrogen is not used as a separate product, but merely as electrical energy storage, it should be evaluated against other and more energy efficient storage options such as pumped hydro and redox flow cells. A probabilistic model of a grid-connected wind power plant with a general energy storage unit is presented in chapter 4. The energy storage unit is applied for smoothing wind power fluctuations by providing a firm power output to the grid over a specific period. The method described in the chapter is based on the statistical properties of the wind speed and a general representation of the wind energy conversion system and the energy storage unit. This method allows us to

On the generalized entropy pseudoadditivity for complex systems

International Nuclear Information System (INIS)

Wang, Qiuping A.; Nivanen, Laurent; Le Mehaute, Alain; Pezeril, Michel

2002-01-01

We show that Abe's general pseudoadditivity for entropy prescribed by thermal equilibrium in nonextensive systems holds not only for entropy, but also for energy. The application of this general pseudoadditivity to Tsallis entropy tells us that the factorization of the probability of a composite system into a product of the probabilities of the subsystems is just a consequence of the existence of thermal equilibrium and not due to the independence of the subsystems. (author)

Paul Scherrer Institute Scientific Report 1999. Volume V: General Energy

Energy Technology Data Exchange (ETDEWEB)

Daum, Christina; Leuenberger, Jakob [eds.

2000-07-01

Strengthening of international collaborations represented a strategic goal of the General Energy Research Department for 1999. For the Fifth Framework Program of the European Union, we participated in consortia and in the successful preparation of several proposals. National networks with partners from academia and Industry have been formed in two topical areas of central interest in the context of sustainability, i.e. 'Ecoefficient energy use and material cycles' and 'Sustainable transportation' on the other hand. Research at PSI comprises all aspects of human energy use, with the ultimate goal of promoting development towards a sustainable energy supply system. In the General Energy Research Department, technologies are being advanced for the utilization of renewable energy sources, low-loss energy storage, efficient conversion, and low emission energy use. Experimental and model-based assessment of these emissions forms the basis of a comprehensive assessment of economic, ecological and environmental consequences, for both present and future energy supply systems. The research program of the department is centered around 1) development, use, and characterisation of catalysts for energy technologies in many different fields, like e.g. the partial oxidation of methanol for hydrogen production, the processing of methane by catalytic combustion and reforming; 2) use of concentrated solar radiation to induce chemical conversions, thereby producing energy carriers; 3) development of efficient, less polluting combustion engines and burners by advancing the detailed understanding of reaction mechanisms and combustion pathways; 4) research and development of low temperature polymer electrolyte fuel cells, novel batteries and capacitors, with applications envisaged for electric vehicles, photovoltaics and on-site load leveling; 5) experimental and model based research concerning transportation and chemistry of atmospheric trace gases related to anthropogenic energy

Paul Scherrer Institute Scientific Report 1999. Volume V: General Energy

International Nuclear Information System (INIS)

Daum, Christina; Leuenberger, Jakob

2000-01-01

Strengthening of international collaborations represented a strategic goal of the General Energy Research Department for 1999. For the Fifth Framework Program of the European Union, we participated in consortia and in the successful preparation of several proposals. National networks with partners from academia and Industry have been formed in two topical areas of central interest in the context of sustainability, i.e. 'Ecoefficient energy use and material cycles' and 'Sustainable transportation' on the other hand. Research at PSI comprises all aspects of human energy use, with the ultimate goal of promoting development towards a sustainable energy supply system. In the General Energy Research Department, technologies are being advanced for the utilization of renewable energy sources, low-loss energy storage, efficient conversion, and low emission energy use. Experimental and model-based assessment of these emissions forms the basis of a comprehensive assessment of economic, ecological and environmental consequences, for both present and future energy supply systems. The research program of the department is centered around 1) development, use, and characterisation of catalysts for energy technologies in many different fields, like e.g. the partial oxidation of methanol for hydrogen production, the processing of methane by catalytic combustion and reforming; 2) use of concentrated solar radiation to induce chemical conversions, thereby producing energy carriers; 3) development of efficient, less polluting combustion engines and burners by advancing the detailed understanding of reaction mechanisms and combustion pathways; 4) research and development of low temperature polymer electrolyte fuel cells, novel batteries and capacitors, with applications envisaged for electric vehicles, photovoltaics and on-site load leveling; 5) experimental and model based research concerning transportation and chemistry of atmospheric trace gases related to anthropogenic energy

Paul Scherrer Institute Scientific Report 1999. Volume V: General Energy

Energy Technology Data Exchange (ETDEWEB)

Daum, Christina; Leuenberger, Jakob [eds.

2000-07-01

Strengthening of international collaborations represented a strategic goal of the General Energy Research Department for 1999. For the Fifth Framework Program of the European Union, we participated in consortia and in the successful preparation of several proposals. National networks with partners from academia and Industry have been formed in two topical areas of central interest in the context of sustainability, i.e. 'Ecoefficient energy use and material cycles' and 'Sustainable transportation' on the other hand. Research at PSI comprises all aspects of human energy use, with the ultimate goal of promoting development towards a sustainable energy supply system. In the General Energy Research Department, technologies are being advanced for the utilization of renewable energy sources, low-loss energy storage, efficient conversion, and low emission energy use. Experimental and model-based assessment of these emissions forms the basis of a comprehensive assessment of economic, ecological and environmental consequences, for both present and future energy supply systems. The research program of the department is centered around 1) development, use, and characterisation of catalysts for energy technologies in many different fields, like e.g. the partial oxidation of methanol for hydrogen production, the processing of methane by catalytic combustion and reforming; 2) use of concentrated solar radiation to induce chemical conversions, thereby producing energy carriers; 3) development of efficient, less polluting combustion engines and burners by advancing the detailed understanding of reaction mechanisms and combustion pathways; 4) research and development of low temperature polymer electrolyte fuel cells, novel batteries and capacitors, with applications envisaged for electric vehicles, photovoltaics and on-site load leveling; 5) experimental and model based research concerning transportation and chemistry of atmospheric trace gases related to

Generalized formulation of free energy and application to photosynthesis

Science.gov (United States)

Zhang, Hwe Ik; Choi, M. Y.

2018-03-01

The origin of free energy on the earth is solar radiation. However, the amount of free energy it contains has seldom been investigated, because the free energy concept was believed to be inappropriate for a system of photons. Instead, the origin of free energy has been sought in the process of photosynthesis, imposing a limit of conversion given by the Carnot efficiency. Here we present a general formulation, capable of not only assessing accurately the available amount of free energy in the photon gas but also explaining the primary photosynthetic process more succinctly. In this formulation, the problem of "photosynthetic conversion of the internal energy of photons into the free energy of chlorophyll" is replaced by simple "free energy transduction" between the photons and chlorophyll. An analytic expression for the photosynthetic efficiency is derived and shown to deviate from the Carnot efficiency. Some predictions verifiable possibly by observation are also suggested.

Loss energy states of nonstationary quantum systems

International Nuclear Information System (INIS)

Dodonov, V.V.; Man'ko, V.I.

1978-01-01

The concept of loss energy states is introduced. The loss energy states of the quantum harmonic damping oscillator are considered in detail. The method of constructing the loss energy states for general multidimensional quadratic nonstationary quantum systems is briefly discussed

Alternative Energy Systems

Energy Technology Data Exchange (ETDEWEB)

West, M.; Duckers, L.; Lockett, P.; Loughridge, B.; Peatfield, T.; White, P.

1984-01-01

The Coventry (Lanchester) Polytechnic Wave Energy Group has been involved in the United Kingdom wave energy research programme since its inception in 1975. Whilst the work of the group is mainly concerned with wave energy, and currently is directed towards the design of a wave energy device tailored to the needs of isolated/island communities, it has some involvement with other aspects of the alternatives. This conference, dealing with alternative energy systems and their electrical integration and utilisation was engendered by the general interest which the Polytechnic group members have in the alternatives and their use. The scope for electrical integration and utilisation is very broad. Energy for family groups may be provided in a relatively unsophisticated way which is acceptable to them. Small population centres, for example island communities relying upon diesel equipment, can reap the benefits of the alternatives through their ability to accept novel integration schemes and a flexible approach to the use of the energy available. Consumers already enjoying the benefits of a 'firm' electricity grid supply can use energy from a variety of alternative systems, via the grid, without having to modify their energy consumption habits. In addition to the domestic and industrial applications and coastal possibilities, specialist applications in isolated environments have also emerged. The Proceedings detail practical, technical and economic aspects of the alternatives and their electrical integration and utilisation.

Covariant generalized holographic dark energy and accelerating universe

Energy Technology Data Exchange (ETDEWEB)

Nojiri, Shin' ichi [Nagoya University, Department of Physics, Nagoya (Japan); Nagoya University, Kobayashi-Maskawa Institute for the Origin of Particles and the Universe, Nagoya (Japan); Odintsov, S.D. [ICREA, Barcelona (Spain); Institute of Space Sciences (IEEC-CSIC), Barcelona (Spain); National Research Tomsk State University, Tomsk (Russian Federation); Tomsk State Pedagogical University, Tomsk (Russian Federation)

2017-08-15

We propose the generalized holographic dark energy model where the infrared cutoff is identified with the combination of the FRW universe parameters: the Hubble rate, particle and future horizons, cosmological constant, the universe lifetime (if finite) and their derivatives. It is demonstrated that with the corresponding choice of the cutoff one can map such holographic dark energy to modified gravity or gravity with a general fluid. Explicitly, F(R) gravity and the general perfect fluid are worked out in detail and the corresponding infrared cutoff is found. Using this correspondence, we get realistic inflation or viable dark energy or a unified inflationary-dark energy universe in terms of covariant holographic dark energy. (orig.)

Covariant generalized holographic dark energy and accelerating universe

International Nuclear Information System (INIS)

Nojiri, Shin'ichi; Odintsov, S.D.

2017-01-01

We propose the generalized holographic dark energy model where the infrared cutoff is identified with the combination of the FRW universe parameters: the Hubble rate, particle and future horizons, cosmological constant, the universe lifetime (if finite) and their derivatives. It is demonstrated that with the corresponding choice of the cutoff one can map such holographic dark energy to modified gravity or gravity with a general fluid. Explicitly, F(R) gravity and the general perfect fluid are worked out in detail and the corresponding infrared cutoff is found. Using this correspondence, we get realistic inflation or viable dark energy or a unified inflationary-dark energy universe in terms of covariant holographic dark energy. (orig.)

Covariant generalized holographic dark energy and accelerating universe

Science.gov (United States)

Nojiri, Shin'ichi; Odintsov, S. D.

2017-08-01

We propose the generalized holographic dark energy model where the infrared cutoff is identified with the combination of the FRW universe parameters: the Hubble rate, particle and future horizons, cosmological constant, the universe lifetime (if finite) and their derivatives. It is demonstrated that with the corresponding choice of the cutoff one can map such holographic dark energy to modified gravity or gravity with a general fluid. Explicitly, F( R) gravity and the general perfect fluid are worked out in detail and the corresponding infrared cutoff is found. Using this correspondence, we get realistic inflation or viable dark energy or a unified inflationary-dark energy universe in terms of covariant holographic dark energy.

Advanced Grid Control Technologies Workshop Series | Energy Systems

Science.gov (United States)

: Smart Grid and Beyond John McDonald, Director, Technical Strategy and Policy Development, General Control Technologies Workshop Series In July 2015, NREL's energy systems integration team hosted workshops the Energy Systems Integration Facility (ESIF) and included a technology showcase featuring projects

Wind energy systems

International Nuclear Information System (INIS)

Richardson, R.D.; McNerney, G.M.

1993-01-01

Wind energy has matured to a level of development where it is ready to become a generally accepted utility generation technology. A brief discussion of this development is presented, and the operating and design principles are discussed. Alternative designs for wind turbines and the tradeoffs that must be considered are briefly compared. Development of a wind energy system and the impacts on the utility network including frequency stability, voltage stability, and power quality are discussed. The assessment of wind power station economics and the key economic factors that determine the economic viability of a wind power plant are presented

State energy-price system: 1981 update

Energy Technology Data Exchange (ETDEWEB)

Fang, J.M.; Imhoff, K.L.; Hood, L.J.

1983-08-01

This report updates the State Energy Price Data System (STEPS) to include state-level energy prices by fuel and by end-use sectors for 1981. Both physical unit prices and Btu prices are presented. Basic documentation of the data base remains generally the same as in the original report: State Energy Price System; Volume 1: Overview and Technical Documentation (DOE/NBB-0029 Volume 1 of 2, November 1982). The present report documents only the changes in procedures necessitated by the update to 1981 and the corrections to the basic documentation.

Energy innovation systems indicator report 2012

Energy Technology Data Exchange (ETDEWEB)

Borup, M. [Technical Univ. of Denmark. DTU Management Engineering, Kgs. Lyngby (Denmark); Klitkou, A.; Iversen, E. [Nordic Institute for Studies in Innovation, Research and Education, Oslo (Norway)

2012-12-15

Knowledge about the innovation systems with respect to new energy solutions and technologies is of central importance for understanding the dynamics of change in the energy sector and assessment of opportunities for moving towards more climate-friendly and sustainable energy systems and for socio-economic development in the field, creation of new businesses, work places, etc.. This is the topic that in general is addressed in the research activities of the ''EIS - Strategic research alliance for Energy Innovation Systems and their dynamics - Denmark in global competition''. As part of this, the present report gives an overview of the available indicators of energy innovation systems and points out some of the limitations and potentials there currently are in this connection. Focus is on Denmark. Figures for other countries, primarily Nordic or European, are in some cases showed as well, offering a comparative perspective. (Author)

Exergy Analysis of Complex Ship Energy Systems

Directory of Open Access Journals (Sweden)

Pierre Marty

2016-04-01

Full Text Available With multiple primary and secondary energy converters (diesel engines, steam turbines, waste heat recovery (WHR and oil-fired boilers, etc. and extensive energy networks (steam, cooling water, exhaust gases, etc., ships may be considered as complex energy systems. Understanding and optimizing such systems requires advanced holistic energy modeling. This modeling can be done in two ways: The simpler approach focuses on energy flows, and has already been tested, approved and presented; a new, more complicated approach, focusing on energy quality, i.e., exergy, is presented in this paper. Exergy analysis has rarely been applied to ships, and, as a general rule, the shipping industry is not familiar with this tool. This paper tries to fill this gap. We start by giving a short reminder of what exergy is and describe the principles of exergy modeling to explain what kind of results should be expected from such an analysis. We then apply these principles to the analysis of a large two-stroke diesel engine with its cooling and exhaust systems. Simulation results are then presented along with the exergy analysis. Finally, we propose solutions for energy and exergy saving which could be applied to marine engines and ships in general.

Multiple Energy System Analysis of Smart Energy Systems

DEFF Research Database (Denmark)

Thellufsen, Jakob Zinck

2015-01-01

thermal grids and smart gas grids, Smart Energy Systems moves the flexibility away from the fuel as is the case in current energy systems and into the system itself. However, most studies applying a Smart Energy System approach deals with analyses for either single countries or whole continents......To eliminate the use of fossil fuels in the energy sector it is necessary to transition to future 100% renewable energy systems. One approach for this radical change in our energy systems is Smart Energy Systems. With a focus on development and interaction between smart electricity grids, smart......, but it is unclear how regions, municipalities, and communities should deal with these national targets. It is necessary to be able to provide this information since Smart Energy Systems utilize energy resources and initiatives that have strong relations to local authorities and communities, such as onshore wind...

Solar thermal energy utilization. German studies on technology and application. Vol. 1. General investigations on energy availability

Energy Technology Data Exchange (ETDEWEB)

Becker, M. (Deutsche Forschungs- und Versuchsanstalt fuer Luft- und Raumfahrt e.V. (DFVLR), Koeln (Germany, F.R.). Hauptabteilung Energietechnik) (ed.)

1987-01-01

The first volume of a three-volume series titled 'Solar thermal energy utilization' comprises three papers dealing with general investigations into energy availability. Their titles are: Yearly yield of solar CRS-process heat and temperature of reaction; - literature survey in the field of primary and secondary concentrating solar energy systems concerning the choice and manufacturing process of suitable materials; - considerations and proposals for future research and development of high temperature solar processes. Each of the three chapters was abstracted for entry into the database. (HWJ).

Design and Realization of Online Monitoring System of Distributed New Energy and Renewable Energy

Science.gov (United States)

Tang, Yanfen; Zhou, Tao; Li, Mengwen; Zheng, Guotai; Li, Hao

2018-01-01

Aimed at difficult centralized monitoring and management of current distributed new energy and renewable energy generation projects due to great varieties, different communication protocols and large-scale difference, this paper designs a online monitoring system of new energy and renewable energy characterized by distributed deployment, tailorable functions, extendible applications and fault self-healing performance. This system is designed based on international general standard for grid information data model, formulates unified data acquisition and transmission standard for different types of new energy and renewable energy generation projects, and can realize unified data acquisition and real-time monitoring of new energy and renewable energy generation projects, such as solar energy, wind power, biomass energy, etc. within its jurisdiction. This system has applied in Beijing. At present, 576 projects are connected to the system. Good effect is achieved and stability and reliability of the system have been validated.

Constraints on stress-energy perturbations in general relativity

International Nuclear Information System (INIS)

Traschen, J.

1985-01-01

Conditions are found for the existence of integral constraints on stress-energy perturbations in general relativity. The integral constraints can be thought of as a general-relativistic generalization of the conservation of energy and momentum of matter perturbations in special relativity. The constraints are stated in terms of a vector field V, and the Robertson-Walker spacetimes are shown to have such constraint vectors. Although in general V is not a Killing vector, in a vacuum spacetime the constraint vectors are precisely the Killing vectors

Boundary conditions, energies and gravitational heat in general relativity (a classical analysis)

International Nuclear Information System (INIS)

Francaviglia, M; Raiteri, M

2004-01-01

The variation of the energy for a gravitational system is directly defined from the Hamiltonian field equations of general relativity. When the variation of the energy is written in a covariant form, it splits into two (covariant) contributions: one of them is the Komar energy, while the other is the so-called covariant ADM correction term. When specific boundary conditions are analysed one sees that the Komar energy is related to the gravitational heat while the ADM correction term plays the role of the Helmholtz free energy. These properties allow one to establish, inside a classical geometric framework, a formal analogy between gravitation and the laws governing the evolution of a thermodynamical system. The analogy applies to stationary spacetimes admitting multiple causal horizons as well as to AdS Taub-bolt solutions

Simple implementation of general dark energy models

International Nuclear Information System (INIS)

Bloomfield, Jolyon K.; Pearson, Jonathan A.

2014-01-01

We present a formalism for the numerical implementation of general theories of dark energy, combining the computational simplicity of the equation of state for perturbations approach with the generality of the effective field theory approach. An effective fluid description is employed, based on a general action describing single-scalar field models. The formalism is developed from first principles, and constructed keeping the goal of a simple implementation into CAMB in mind. Benefits of this approach include its straightforward implementation, the generality of the underlying theory, the fact that the evolved variables are physical quantities, and that model-independent phenomenological descriptions may be straightforwardly investigated. We hope this formulation will provide a powerful tool for the comparison of theoretical models of dark energy with observational data

What Is Energy Systems Integration? | Energy Systems Integration Facility |

Science.gov (United States)

NREL What Is Energy Systems Integration? What Is Energy Systems Integration? Energy systems integration (ESI) is an approach to solving big energy challenges that explores ways for energy systems to Research Community NREL is a founding member of the International Institute for Energy Systems Integration

Paul Scherrer Institut Scientific Report 2004. Volume V: General Energy

Energy Technology Data Exchange (ETDEWEB)

Wokaun, Alexander; Daum, Christina (eds.)

2005-03-01

Research at PSI comprises all aspects of human energy use, with the ultimate goal of promoting development towards a sustainable energy supply system. In the General Energy Research Department, technologies are being advanced for the utilization of renewable energy sources, low-loss energy storage, efficient conversion, and low emission energy use. Experimental and model-based assessment of these emissions forms the basis of a comprehensive assessment of economic, ecological and environmental consequences, for both present and future energy supply systems. The research program of the department is centered around 1) development, use, and characterisation of catalysts for energy technologies in many different fields, like e.g. the partial oxidation of methanol for hydrogen production, the processing of methane by catalytic combustion and reforming; 2) use of concentrated solar radiation to induce chemical conversions, thereby producing energy carriers; 3) development of efficient, less polluting combustion engines and burners by advancing the detailed understanding of reaction mechanisms and combustion pathways; 4) research and development of low temperature polymer electrolyte fuel cells, novel batteries and capacitors, with applications envisaged for electric vehicles, photovoltaics and on-site load leveling; 5) experimental and model based research concerning transportation and chemistry of atmospheric trace gases related to anthropogenic energy transformations. Progress in 2000 in these topical areas is described in this report. A list of scientific publications in 2002 is also provided.

Paul Scherrer Institut Scientific Report 2001. Volume V: General Energy

Energy Technology Data Exchange (ETDEWEB)

Wokaun, Alexander; Daum, Christina [eds.

2002-03-01

Research at PSI comprises all aspects of human energy use, with the ultimate goal of promoting development towards a sustainable energy supply system. In the General Energy Research Department, technologies are being advanced for the utilization of renewable energy sources, low-loss energy storage, efficient conversion, and low emission energy use. Experimental and model-based assessment of these emissions forms the basis of a comprehensive assessment of economic, ecological and environmental consequences, for both present and future energy supply systems. The research program of the department is centered around 1) development, use, and characterisation of catalysts for energy technologies in many different fields, like e.g. the partial oxidation of methanol for hydrogen production, the processing of methane by catalytic combustion and reforming; 2) use of concentrated solar radiation to induce chemical conversions, thereby producing energy carriers; 3) development of efficient, less polluting combustion engines and burners by advancing the detailed understanding of reaction mechanisms and combustion pathways; 4) research and development of low temperature polymer electrolyte fuel cells, novel batteries and capacitors, with applications envisaged for electric vehicles, photovoltaics and on-site load leveling; 5) experimental and model based research concerning transportation and chemistry of atmospheric trace gases related to anthropogenic energy transformations. Progress in 2000 in these topical areas is described in this report. A list of scientific publications in 2001 is also provided.

Paul Scherrer Institute Scientific Report 2000. Volume V: General Energy

Energy Technology Data Exchange (ETDEWEB)

Daum, Christina; Leuenberger, Jakob [eds.

2001-07-01

Research at PSI comprises all aspects of human energy use, with the ultimate goal of promoting development towards a sustainable energy supply system. In the General Energy Research Department, technologies are being advanced for the utilization of renewable energy sources, low-loss energy storage, efficient conversion, and low emission energy use. Experimental and model-based assessment of these emissions forms the basis of a comprehensive assessment of economic, ecological and environmental consequences, for both present and future energy supply systems. The research program of the department is centered around 1) development, use, and characterisation of catalysts for energy technologies in many different fields, like e.g. the partial oxidation of methanol for hydrogen production, the processing of methane by catalytic combustion and reforming; 2) use of concentrated solar radiation to induce chemical conversions, thereby producing energy carriers; 3) development of efficient, less polluting combustion engines and burners by advancing the detailed understanding of reaction mechanisms and combustion pathways; 4) research and development of low temperature polymer electrolyte fuel cells, novel batteries and capacitors, with applications envisaged for electric vehicles, photovoltaics and on-site load leveling; 5) experimental and model based research concerning transportation and chemistry of atmospheric trace gases related to anthropogenic energy transformations. Progress in 2000 in these topical areas is described in this report. A list of scientific publications in 2000 is also provided.

Paul Scherrer Institute Scientific Report 2000. Volume V: General Energy

Energy Technology Data Exchange (ETDEWEB)

Daum, Christina; Leuenberger, Jakob [eds.

2001-03-01

Research at PSI comprises all aspects of human energy use, with the ultimate goal of promoting development towards a sustainable energy supply system. In the General Energy Research Department, technologies are being advanced for the utilization of renewable energy sources, low-loss energy storage, efficient conversion, and low emission energy use. Experimental and model-based assessment of these emissions forms the basis of a comprehensive assessment of economic, ecological and environmental consequences, for both present and future energy supply systems. The research program of the department is centered around (1) development, use, and characterisation of catalysts for energy technologies in many different fields, like e.g. the partial oxidation of methanol for hydrogen production, the processing of methane by catalytic combustion and reforming; (2) use of concentrated solar radiation to induce chemical conversions, thereby producing energy carriers; (3) development of efficient, less polluting combustion engines and burners by advancing the detailed understanding of reaction mechanisms and combustion pathways; (4) research and development of low temperature polymer electrolyte fuel cells, novel batteries and capacitors, with applications envisaged for electric vehicles, photovoltaics and on-site load leveling; (5) experimental and model based research concerning transportation and chemistry of atmospheric trace gases related to anthropogenic energy transformations. Progress in 2000 in these topical areas is described in this report. A list of scientific publications in 2000 is also provided.

Paul Scherrer Institut Scientific Report 2002. Volume V: General Energy

Energy Technology Data Exchange (ETDEWEB)

Wokaun, Alexander; Daum, Christina [eds.

2003-03-01

Research at PSI comprises all aspects of human energy use, with the ultimate goal of promoting development towards a sustainable energy supply system. In the General Energy Research Department, technologies are being advanced for the utilization of renewable energy sources, low-loss energy storage, efficient conversion, and low emission energy use. Experimental and model-based assessment of these emissions forms the basis of a comprehensive assessment of economic, ecological and environmental consequences, for both present and future energy supply systems. The research program of the department is centered around 1) development, use, and characterisation of catalysts for energy technologies in many different fields, like e.g. the partial oxidation of methanol for hydrogen production, the processing of methane by catalytic combustion and reforming; 2) use of concentrated solar radiation to induce chemical conversions, thereby producing energy carriers; 3) development of efficient, less polluting combustion engines and burners by advancing the detailed understanding of reaction mechanisms and combustion pathways; 4) research and development of low temperature polymer electrolyte fuel cells, novel batteries and capacitors, with applications envisaged for electric vehicles, photovoltaics and on-site load leveling; 5) experimental and model based research concerning transportation and chemistry of atmospheric trace gases related to anthropogenic energy transformations. Progress in 2000 in these topical areas is described in this report. A list of scientific publications in 2002 is also provided.

Paul Scherrer Institute Scientific Report 2000. Volume V: General Energy

International Nuclear Information System (INIS)

Daum, Christina; Leuenberger, Jakob

2001-01-01

Research at PSI comprises all aspects of human energy use, with the ultimate goal of promoting development towards a sustainable energy supply system. In the General Energy Research Department, technologies are being advanced for the utilization of renewable energy sources, low-loss energy storage, efficient conversion, and low emission energy use. Experimental and model-based assessment of these emissions forms the basis of a comprehensive assessment of economic, ecological and environmental consequences, for both present and future energy supply systems. The research program of the department is centered around 1) development, use, and characterisation of catalysts for energy technologies in many different fields, like e.g. the partial oxidation of methanol for hydrogen production, the processing of methane by catalytic combustion and reforming; 2) use of concentrated solar radiation to induce chemical conversions, thereby producing energy carriers; 3) development of efficient, less polluting combustion engines and burners by advancing the detailed understanding of reaction mechanisms and combustion pathways; 4) research and development of low temperature polymer electrolyte fuel cells, novel batteries and capacitors, with applications envisaged for electric vehicles, photovoltaics and on-site load leveling; 5) experimental and model based research concerning transportation and chemistry of atmospheric trace gases related to anthropogenic energy transformations. Progress in 2000 in these topical areas is described in this report. A list of scientific publications in 2000 is also provided

Paul Scherrer Institut Scientific Report 2003. Volume V: General Energy

International Nuclear Information System (INIS)

Wokaun, A.; Daum, C.

2004-03-01

Research at PSI comprises all aspects of human energy use, with the ultimate goal of promoting development towards a sustainable energy supply system. In the General Energy Research Department, technologies are being advanced for the utilization of renewable energy sources, low-loss energy storage, efficient conversion, and low emission energy use. Experimental and model-based assessment of these emissions forms the basis of a comprehensive assessment of economic, ecological and environmental consequences, for both present and future energy supply systems. The research program of the department is centered around 1) development, use, and characterisation of catalysts for energy technologies in many different fields, like e.g. the partial oxidation of methanol for hydrogen production, the processing of methane by catalytic combustion and reforming; 2) use of concentrated solar radiation to induce chemical conversions, thereby producing energy carriers; 3) development of efficient, less polluting combustion engines and burners by advancing the detailed understanding of reaction mechanisms and combustion pathways; 4) research and development of low temperature polymer electrolyte fuel cells, novel batteries and capacitors, with applications envisaged for electric vehicles, photovoltaics and on-site load leveling; 5) experimental and model based research concerning transportation and chemistry of atmospheric trace gases related to anthropogenic energy transformations. Progress in 2000 in these topical areas is described in this report. A list of scientific publications in 2002 is also provided

Paul Scherrer Institut Scientific Report 2004. Volume V: General Energy

International Nuclear Information System (INIS)

Wokaun, A.; Daum, C.

2005-01-01

Research at PSI comprises all aspects of human energy use, with the ultimate goal of promoting development towards a sustainable energy supply system. In the General Energy Research Department, technologies are being advanced for the utilization of renewable energy sources, low-loss energy storage, efficient conversion, and low emission energy use. Experimental and model-based assessment of these emissions forms the basis of a comprehensive assessment of economic, ecological and environmental consequences, for both present and future energy supply systems. The research program of the department is centered around 1) development, use, and characterisation of catalysts for energy technologies in many different fields, like e.g. the partial oxidation of methanol for hydrogen production, the processing of methane by catalytic combustion and reforming; 2) use of concentrated solar radiation to induce chemical conversions, thereby producing energy carriers; 3) development of efficient, less polluting combustion engines and burners by advancing the detailed understanding of reaction mechanisms and combustion pathways; 4) research and development of low temperature polymer electrolyte fuel cells, novel batteries and capacitors, with applications envisaged for electric vehicles, photovoltaics and on-site load leveling; 5) experimental and model based research concerning transportation and chemistry of atmospheric trace gases related to anthropogenic energy transformations. Progress in 2000 in these topical areas is described in this report. A list of scientific publications in 2002 is also provided

Paul Scherrer Institut Scientific Report 2002. Volume V: General Energy

International Nuclear Information System (INIS)

Wokaun, A.; Daum, C.

2003-03-01

Research at PSI comprises all aspects of human energy use, with the ultimate goal of promoting development towards a sustainable energy supply system. In the General Energy Research Department, technologies are being advanced for the utilization of renewable energy sources, low-loss energy storage, efficient conversion, and low emission energy use. Experimental and model-based assessment of these emissions forms the basis of a comprehensive assessment of economic, ecological and environmental consequences, for both present and future energy supply systems. The research program of the department is centered around 1) development, use, and characterisation of catalysts for energy technologies in many different fields, like e.g. the partial oxidation of methanol for hydrogen production, the processing of methane by catalytic combustion and reforming; 2) use of concentrated solar radiation to induce chemical conversions, thereby producing energy carriers; 3) development of efficient, less polluting combustion engines and burners by advancing the detailed understanding of reaction mechanisms and combustion pathways; 4) research and development of low temperature polymer electrolyte fuel cells, novel batteries and capacitors, with applications envisaged for electric vehicles, photovoltaics and on-site load leveling; 5) experimental and model based research concerning transportation and chemistry of atmospheric trace gases related to anthropogenic energy transformations. Progress in 2000 in these topical areas is described in this report. A list of scientific publications in 2002 is also provided

Paul Scherrer Institut Scientific Report 2003. Volume V: General Energy

Energy Technology Data Exchange (ETDEWEB)

Wokaun, Alexander; Daum, Christina (eds.)

2004-03-01

Research at PSI comprises all aspects of human energy use, with the ultimate goal of promoting development towards a sustainable energy supply system. In the General Energy Research Department, technologies are being advanced for the utilization of renewable energy sources, low-loss energy storage, efficient conversion, and low emission energy use. Experimental and model-based assessment of these emissions forms the basis of a comprehensive assessment of economic, ecological and environmental consequences, for both present and future energy supply systems. The research program of the department is centered around 1) development, use, and characterisation of catalysts for energy technologies in many different fields, like e.g. the partial oxidation of methanol for hydrogen production, the processing of methane by catalytic combustion and reforming; 2) use of concentrated solar radiation to induce chemical conversions, thereby producing energy carriers; 3) development of efficient, less polluting combustion engines and burners by advancing the detailed understanding of reaction mechanisms and combustion pathways; 4) research and development of low temperature polymer electrolyte fuel cells, novel batteries and capacitors, with applications envisaged for electric vehicles, photovoltaics and on-site load leveling; 5) experimental and model based research concerning transportation and chemistry of atmospheric trace gases related to anthropogenic energy transformations. Progress in 2000 in these topical areas is described in this report. A list of scientific publications in 2002 is also provided.

Optimization Models and Methods Developed at the Energy Systems Institute

OpenAIRE

N.I. Voropai; V.I. Zorkaltsev

2013-01-01

The paper presents shortly some optimization models of energy system operation and expansion that have been created at the Energy Systems Institute of the Siberian Branch of the Russian Academy of Sciences. Consideration is given to the optimization models of energy development in Russia, a software package intended for analysis of power system reliability, and model of flow distribution in hydraulic systems. A general idea of the optimization methods developed at the Energy Systems Institute...

Energy conditions and stability in general relativity

International Nuclear Information System (INIS)

Hall, G.S.

1982-01-01

The dominant energy condition in general relativity theory, which says that every observer measures a nonnegative local energy density and a nonspacelike local energy flow, is examined in connection with the types of energy-momentum tensor it permits. The condition that the energy-momentum tensor be ''stable'' in obeying the dominant energy conditions is then defined in terms of a suitable topology on the set of energy-momentum tensors on space-time and the consequences are evaluated and discussed. (author)

Multireference Density Functional Theory with Generalized Auxiliary Systems for Ground and Excited States.

Science.gov (United States)

Chen, Zehua; Zhang, Du; Jin, Ye; Yang, Yang; Su, Neil Qiang; Yang, Weitao

2017-09-21

To describe static correlation, we develop a new approach to density functional theory (DFT), which uses a generalized auxiliary system that is of a different symmetry, such as particle number or spin, from that of the physical system. The total energy of the physical system consists of two parts: the energy of the auxiliary system, which is determined with a chosen density functional approximation (DFA), and the excitation energy from an approximate linear response theory that restores the symmetry to that of the physical system, thus rigorously leading to a multideterminant description of the physical system. The electron density of the physical system is different from that of the auxiliary system and is uniquely determined from the functional derivative of the total energy with respect to the external potential. Our energy functional is thus an implicit functional of the physical system density, but an explicit functional of the auxiliary system density. We show that the total energy minimum and stationary states, describing the ground and excited states of the physical system, can be obtained by a self-consistent optimization with respect to the explicit variable, the generalized Kohn-Sham noninteracting density matrix. We have developed the generalized optimized effective potential method for the self-consistent optimization. Among options of the auxiliary system and the associated linear response theory, reformulated versions of the particle-particle random phase approximation (pp-RPA) and the spin-flip time-dependent density functional theory (SF-TDDFT) are selected for illustration of principle. Numerical results show that our multireference DFT successfully describes static correlation in bond dissociation and double bond rotation.

The energy and the linear momentum of space-times in general relativity

International Nuclear Information System (INIS)

Schoen, R.; Yau, S.T.

1981-01-01

We extend our previous proof of the positive mass conjecture to allow a more general asymptotic condition proposed by York. Hence we are able to prove that for an isolated physical system, the energy momentum four vector is a future timelike vector unless the system is trivial. Furthermore, we allow singularities of the type of black holes. (orig.)

Surface energy and radiation balance systems - General description and improvements

Science.gov (United States)

Fritschen, Leo J.; Simpson, James R.

1989-01-01

Surface evaluation of sensible and latent heat flux densities and the components of the radiation balance were desired for various vegetative surfaces during the ASCOT84 experiment to compare with modeled results and to relate these values to drainage winds. Five battery operated data systems equipped with sensors to determine the above values were operated for 105 station days during the ASCOT84 experiment. The Bowen ratio energy balance technique was used to partition the available energy into the sensible and latent heat flux densities. A description of the sensors and battery operated equipment used to collect and process the data is presented. In addition, improvements and modifications made since the 1984 experiment are given. Details of calculations of soil heat flow at the surface and an alternate method to calculate sensible and latent heat flux densities are provided.

Applied research on energy storage and conversion for photovoltaic and wind energy systems. Volume II. Photovoltaic systems with energy storage. Final report

Energy Technology Data Exchange (ETDEWEB)

1978-01-01

This volume of the General Electric study was directed at an evaluation of those energy storage technologies deemed best suited for use in conjunction with a photovoltaic energy conversion system in utility, residential and intermediate applications. Break-even cost goals are developed for several storage technologies in each application. These break-even costs are then compared with cost projections presented in Volume I of this report to show technologies and time frames of potential economic viability. The form of the presentation allows the reader to use more accurate storage system cost data as they become available. The report summarizes the investigations performed and presents the results, conclusions and recommendations pertaining to use of energy storage with photovoltaic energy conversion systems. Candidate storage concepts studied include (1) above ground and underground pumped hydro, (2) underground compressed air, (3) electric batteries, (4) flywheels, and (5) hydrogen production and storage. (WHK)

Energy Systems Integration Facility News | Energy Systems Integration

Science.gov (United States)

Facility | NREL Energy Systems Integration Facility News Energy Systems Integration Facility Energy Dataset A massive amount of wind data was recently made accessible online, greatly expanding the Energy's National Renewable Energy Laboratory (NREL) has completed technology validation testing for Go

Generalized Least Energy of Separation for Desalination and Other Chemical Separation Processes

Directory of Open Access Journals (Sweden)

Karan H. Mistry

2013-05-01

Full Text Available Increasing global demand for fresh water is driving the development and implementation of a wide variety of seawater desalination technologies driven by different combinations of heat, work, and chemical energy. This paper develops a consistent basis for comparing the energy consumption of such technologies using Second Law efficiency. The Second Law efficiency for a chemical separation process is defined in terms of the useful exergy output, which is the minimum least work of separation required to extract a unit of product from a feed stream of a given composition. For a desalination process, this is the minimum least work of separation for producing one kilogram of product water from feed of a given salinity. While definitions in terms of work and heat input have been proposed before, this work generalizes the Second Law efficiency to allow for systems that operate on a combination of energy inputs, including fuel. The generalized equation is then evaluated through a parametric study considering work input, heat inputs at various temperatures, and various chemical fuel inputs. Further, since most modern, large-scale desalination plants operate in cogeneration schemes, a methodology for correctly evaluating Second Law efficiency for the desalination plant based on primary energy inputs is demonstrated. It is shown that, from a strictly energetic point of view and based on currently available technology, cogeneration using electricity to power a reverse osmosis system is energetically superior to thermal systems such as multiple effect distillation and multistage flash distillation, despite the very low grade heat input normally applied in those systems.

Multidimensional generalized-ensemble algorithms for complex systems.

Science.gov (United States)

Mitsutake, Ayori; Okamoto, Yuko

2009-06-07

We give general formulations of the multidimensional multicanonical algorithm, simulated tempering, and replica-exchange method. We generalize the original potential energy function E(0) by adding any physical quantity V of interest as a new energy term. These multidimensional generalized-ensemble algorithms then perform a random walk not only in E(0) space but also in V space. Among the three algorithms, the replica-exchange method is the easiest to perform because the weight factor is just a product of regular Boltzmann-like factors, while the weight factors for the multicanonical algorithm and simulated tempering are not a priori known. We give a simple procedure for obtaining the weight factors for these two latter algorithms, which uses a short replica-exchange simulation and the multiple-histogram reweighting techniques. As an example of applications of these algorithms, we have performed a two-dimensional replica-exchange simulation and a two-dimensional simulated-tempering simulation using an alpha-helical peptide system. From these simulations, we study the helix-coil transitions of the peptide in gas phase and in aqueous solution.

Analysis of a general circulation model. II - Distribution of kinetic energy in the South Atlantic and Kuroshio/Oyashio systems

Science.gov (United States)

Garraffo, Zulema; Garzoli, Silvia L.; Haxby, William; Olson, Donald

1992-01-01

It was found (Garzoli et al., 1992) that the general circulation model of Semtner and Chervin (1992) provides accurate descriptions of the Brazil-Malvinas and the Kuroshio/Oyashio confluence systems, except for the fact that the model prediction shows less variability than that present in observations. This paper investigates the problem of model variability by analyzing the mean and the eddy kinetic energy from the model and comparing the values with the Geosat altimeter observations for the South Atlantic Ocean and for the Kuroshio system. It is found that, while the model shows transient eddy activity in the areas that overlap the Geosat observations, the energy level of the model transient motions is considerably smaller following an arch along the bottom topography. The same was found from the comparisons made with values obtained from FGGE and surface drifters. It is suggested that the model is poorly resolving instabilities in the confluence front, and is not resolving other transients appearing in regions of marked topography.

Generalized Energy-Dependent Q Values for Fission

Energy Technology Data Exchange (ETDEWEB)

Vogt, R

2010-03-31

We extend Madland's parameterization of the energy release in fission to obtain the dependence of the fission Q value for major and minor actinides on the incident neutron energies in the range 0 {le} E{sub n} {le} 20 MeV. Our parameterization is based on the actinide evaluations recommended for the ENDF/B-VII.1 release. This paper describes the calculation of energydependent fission Q values based on the calculation of the prompt energy release in fission by Madland. This calculation was adopted for use in the LLNL ENDL database and then generalized to obtain the prompt fission energy release for all actinides. Here the calculation is further generalized to the total energy release in fission. There are several stages in a fission event, depending on the time scale. Neutrons and gammas may be emitted at any time during the fission event.While our discussion here is focussed on compound nucleus creation by an incident neutron, similar parameterizations could be obtained for incident gammas or spontaneous fission.

Kerr-Taub-NUT General Frame, Energy, and Momentum in Teleparallel Equivalent of General Relativity

Directory of Open Access Journals (Sweden)

Gamal G. L. Nashed

2012-01-01

Full Text Available A new exact solution describing a general stationary and axisymmetric object of the gravitational field in the framework of teleparallel equivalent of general relativity (TEGR is derived. The solution is characterized by three parameters “the gravitational mass M, the rotation a, and the NUT L.” The vierbein field is axially symmetric, and the associated metric gives the Kerr-Taub-NUT spacetime. Calculation of the total energy using two different methods, the gravitational energy momentum and the Riemannian connection 1-form Γα̃β, is carried out. It is shown that the two methods give the same results of energy and momentum. The value of energy is shown to depend on the mass M and the NUT parameter L. If L is vanishing, then the total energy reduced to the energy of Kerr black hole.

Generalized fast feedback system in the SLC

International Nuclear Information System (INIS)

Hendrickson, L.; Allison, S.; Gromme, T.; Himel, T.; Krauter, K.; Rouse, F.; Sass, R.; Shoaee, H.

1991-11-01

A generalized fast feedback system has been developed to stabilize beams at various locations in the SLC. The system is designed to perform measurements and change actuator settings to control beam states such as position, angle and energy on a pulse to pulse basis. The software design is based on the state space formalism of digital control theory. The system is database-driven, facilitating the addition of new loops without requiring additional software. A communications system, KISNet, provides fast communications links between microprocessors for feedback loops which involve multiple micros. Feedback loops have been installed in seventeen locations throughout the SLC and have proven to be invaluable in stabilizing the machine

Energy infrastructure: hydrogen energy system

Energy Technology Data Exchange (ETDEWEB)

Veziroglu, T N

1979-02-01

In a hydrogen system, hydrogen is not a primary source of energy, but an intermediary, an energy carrier between the primary energy sources and the user. The new unconventional energy sources, such as nuclear breeder reactors, fusion reactors, direct solar radiation, wind energy, ocean thermal energy, and geothermal energy have their shortcomings. These shortcomings of the new sources point out to the need for an intermediary energy system to form the link between the primary energy sources and the user. In such a system, the intermediary energy form must be transportable and storable; economical to produce; and if possible renewable and pollution-free. The above prerequisites are best met by hydrogen. Hydrogen is plentiful in the form of water. It is the cheapest synthetic fuel to manufacture per unit of energy stored in it. It is the least polluting of all of the fuels, and is the lightest and recyclable. In the proposed system, hydrogen would be produced in large plants located away from the consumption centers at the sites where primary new energy sources and water are available. Hydrogen would then be transported to energy consumption centers where it would be used in every application where fossil fuels are being used today. Once such a system is established, it will never be necessary to change to any other energy system.

Energy Systems Integration News | Energy Systems Integration Facility |

Science.gov (United States)

the Energy Systems Integration Facility as part of NREL's work with SolarCity and the Hawaiian Electric Companies. Photo by Amy Glickson, NREL Welcome to Energy Systems Integration News, NREL's monthly date on the latest energy systems integration (ESI) developments at NREL and worldwide. Have an item

Thermostatistic properties of a q-deformed ideal Fermi gas with a general energy spectrum

International Nuclear Information System (INIS)

Cai, Shukuan; Su, Guozhen; Chen, Jincan

2007-01-01

The thermostatistic problems of a q-deformed ideal Fermi gas in any dimensional space and with a general energy spectrum are studied, based on the q-deformed Fermi-Dirac distribution. The effects of the deformation parameter q on the properties of the system are revealed. It is shown that q-deformation results in some novel characteristics different from those of an ordinary system. Besides, it is found that the effects of the q-deformation on the properties of the Fermi systems are very different for different dimensional spaces and different energy spectrums

Oil Subsidies and Renewable Energy in Saudi Arabia: A General Equilibrium Approach

OpenAIRE

Blazquez, J; Hunt, Lester; Manzano, B

2017-01-01

In 2016, the Kingdom of Saudi Arabia (KSA) announced its Vision 2030 strategic plan incorporating major changes to the economic structure of the country, including an intention to deploy 9.5 GW of renewable energy in an effort to reduce the penetration of oil in the electricity generation system. This paper assesses the macroeconomic impact of such changes in the KSA, coupled with reductions in implicit energy subsidies. Based on a dynamic general equilibrium model, our analysis suggests that...

Energy Conservation In Compressed Air Systems

International Nuclear Information System (INIS)

Yusuf, I.Y.; Dewu, B.B.M.

2004-01-01

Compressed air is an essential utility that accounts for a substantial part of the electricity consumption (bill) in most industrial plants. Although the general saying Air is free of charge is not true for compressed air, the utility's cost is not accorded the rightful importance due to its by most industries. The paper will show that the cost of 1 unit of energy in the form of compressed air is at least 5 times the cost electricity (energy input) required to produce it. The paper will also provide energy conservation tips in compressed air systems

Comparative assessment and management of the health and environmental impacts of energy systems. General framework and preliminary results for the nuclear fuel cycle

Energy Technology Data Exchange (ETDEWEB)

Rostron, W; Schneider, T; Thieme, M; Dreicer, M

1992-06-01

The comparison of the effects of electricity producing systems is of growing importance in decision-making processes for energy planning. This report documents the preliminary results of a project for the CEC-DG XII Radiation Protection Programme on the comparative assessment and management of the health and environmental impacts of energy systems. The work reported in this document has also been supported by EDF - Mission Environnement. In order to profit from the comparative studies already existing, some of the most important ones were surveyed. The aim of these past energy comparison studies was mainly to obtain a global measure of the risks associated with an energy cycle, with a view to ranking the various electricity production systems; but this is now recognised as merely an academic exercise, with a limited impact in decision-making. For energy planning the development of a multi-dimensional approach seems more suitable, as this allows the different types of indicators and measures needed to assess the risks of different energy cycles to be compared. From the past studies it has been seen that health indicators are generally well established, but a weakness is noted with respect to indicators of environmental impacts. This remains a difficult subject, and until such indicators are established, surrogates like concentrations in the environment will have to be used, or qualitative comparisons must suffice. This report presents a general framework allowing for consistent comparisons between different energy systems. The key issues discussed are: assessment by fuel cycle, consideration of the dimensions of time and space, the impact pathway approach for assessing risk, and coherent indicators that can be used to measure the impacts. First results are presented for four activities of the nuclear fuel cycle according to the approach developed: (1) the construction and dismantling of a 900 MWe pressurized water reactor, (2) the transportation of materials between

Energy Systems Integration Laboratory | Energy Systems Integration Facility

Science.gov (United States)

| NREL Integration Laboratory Energy Systems Integration Laboratory Research in the Energy Systems Integration Laboratory is advancing engineering knowledge and market deployment of hydrogen technologies. Applications include microgrids, energy storage for renewables integration, and home- and station

Energy System Analysis of 100 Per cent Renewable Energy Systems

DEFF Research Database (Denmark)

Lund, Henrik; Mathiesen, Brian Vad

2007-01-01

This paper presents the methodology and results of the overall energy system analysis of a 100 per cent renewable energy system. The input for the systems is the result of a project of the Danish Association of Engineers, in which 1600 participants during more than 40 seminars discussed...... and designed a model for the future energy system of Denmark, putting emphasis on energy efficiency, CO2 reduction, and industrial development. The energy system analysis methodology includes hour by hour computer simulations leading to the design of flexible energy systems with the ability to balance...... the electricity supply and demand and to exchange electricity productions on the international electricity markets. The results are detailed system designs and energy balances for two energy target years: year 2050 with 100 per cent renewable energy from biomass and combinations of wind, wave and solar power...

Generalized fast feedback system in the SLC

International Nuclear Information System (INIS)

Hendrickson, L.; Allison, S.; Gromme, T.; Himel, T.; Krauter, K.; Rouse, F.; Sass, R.; Shoaee, H.

1992-01-01

A generalized fast feedback system has been developed to stabilize beams at various locations in the SLC. The system is designed to perform measurements and change actuator settings to control beam states such as position, angle and energy on a pulse to pulse basis. The software design is based on the state space formalism of digital control theory. The system is database-driven, facilitating the addition of new loops without requiring additional software. A communications system, KISNet, provides fast communications links between microprocessors for feedback loops which involve multiple micros. Feedback loops have been installed in seventeen locations throughout the SLC and have proven to be invaluable in stabilizing the machine. (author)

100% Renewable energy systems, climate mitigation and economic growth

DEFF Research Database (Denmark)

Vad Mathiesen, Brian; Lund, Henrik; Karlsson, Kenneth Bernard

2011-01-01

that implementing energy savings, renewable energy and more efficient conversion technologies can have positive socio-economic effects, create employment and potentially lead to large earnings on exports. If externalities such as health effects are included, even more benefits can be expected. 100% Renewable energy......Greenhouse gas mitigation strategies are generally considered costly with world leaders often engaging in debate concerning the costs of mitigation and the distribution of these costs between different countries. In this paper, the analyses and results of the design of a 100% renewable energy...... system by the year 2050 are presented for a complete energy system including transport. Two short-term transition target years in the process towards this goal are analysed for 2015 and 2030. The energy systems are analysed and designed with hour-by-hour energy system analyses. The analyses reveal...

Systems-design and energy-balance considerations for impact fusion

International Nuclear Information System (INIS)

Krakowski, R.A.; Miller, R.L.

1979-01-01

Areas of concern and potential problems for impact fusion are qualitatively considered within an overall systems context. A parametric and qualitative description of the general energy balance and systems considerations for an Impact Fusion Reactor (IFR) design is discussed. Reactor systems design considerations for an IFR are presented. An attempt to assess the IFR viability is made based on highly simplified but limiting projectile-target energy balances and thermonuclear burn models

Energy Systems Integration Facility Videos | Energy Systems Integration

Science.gov (United States)

Facility | NREL Energy Systems Integration Facility Videos Energy Systems Integration Facility Integration Facility NREL + SolarCity: Maximizing Solar Power on Electrical Grids Redefining What's Possible for Renewable Energy: Grid Integration Robot-Powered Reliability Testing at NREL's ESIF Microgrid

Improving energy efficiency of dedicated cooling system and its contribution towards meeting an energy-optimized data center

International Nuclear Information System (INIS)

Cho, Jinkyun; Kim, Yundeok

2016-01-01

Highlights: • Energy-optimized data center’s cooling solutions were derived for four different climate zones. • We studied practical technologies of green data center that greatly improved energy efficiency. • We identified the relationship between mutually dependent factors in datacenter cooling systems. • We evaluated the effect of the dedicated cooling system applications. • Power Usage Effectiveness (PUE) was computed with energy simulation for data centers. - Abstract: Data centers are approximately 50 times more energy-intensive than general buildings. The rapidly increasing energy demand for data center operation has motivated efforts to better understand data center electricity use and to identify strategies that reduce the environmental impact. This research is presented analytical approach to the energy efficiency optimization of high density data center, in a synergy with relevant performance analysis of corresponding case study. This paper builds on data center energy modeling efforts by characterizing climate and cooling system differences among data centers and then evaluating their consequences for building energy use. Representative climate conditions for four regions are applied to data center energy models for several different prototypical cooling types. This includes cooling system, supplemental cooling solutions, design conditions and controlling the environment of ICT equipment were generally used for each climate zone, how these affect energy efficiency, and how the prioritization of system selection is derived. Based on the climate classification and the required operating environmental conditions for data centers suggested by the ASHRAE TC 9.9, a dedicated data center energy evaluation tool was taken to examine the potential energy savings of the cooling technology. Incorporating economizer use into the cooling systems would increase the variation in energy efficiency among geographic regions, indicating that as data centers

Identifying The Most Applicable Renewable Energy Systems Of Iran

Directory of Open Access Journals (Sweden)

Nasibeh Mousavi

2017-03-01

Full Text Available These years because of energy crisis all of country try to find a new way to reduce energy consumptions and obtain maximum use of renewable energy. Iran also is not an exception of this progress. Renewable energy is energy that is provided by renewable sources such as the sun or wind. In general renewable energies are not adaptable to every single community. Because of location and special climate conditions of Iran most applicable renewable energy systems in Iran are solar and wind energy. Main purpose of this paper is to review and identify most applicable renewable energy systems of Iran and also review on traditional and current methods that utilized to obtain maximum use of these renewable energies.

Energy Systems Integration News | Energy Systems Integration Facility |

Science.gov (United States)

organization and independent system operator settle energy transactions in its real-time markets at the same time interval it dispatches energy, and settle operating reserves transactions in its real-time markets the electric grid. These control systems will enable real-time coordination between distributed energy

Energy Systems High-Pressure Test Laboratory | Energy Systems Integration

Science.gov (United States)

Facility | NREL Energy Systems High-Pressure Test Laboratory Energy Systems High-Pressure Test Laboratory In the Energy Systems Integration Facility's High-Pressure Test Laboratory, researchers can safely test high-pressure hydrogen components. Photo of researchers running an experiment with a hydrogen fuel

The notion of general interest in the energy field

International Nuclear Information System (INIS)

Bauby, P.

2008-01-01

The 1980's have been marked by a reversal of the reference paradigm concerning the manner in which energy issues are tackled: whilst during the whole period following the Second World War, primacy was placed on the pursuit of general interest in energy policies like in the industrial forms of organisation, the issues have tended to be tackled first of all in terms of 'markets', particularly in Europe and in developed countries. This article aims to raise once more and redefine energy issues, not using the opposition and exclusion between markets and general interest as a reference, but their relations and interactions as they are constructed, in particular within the framework of European integration processes. After giving a reminder of the essence of 'general interest', it will examine the energy issues in Europe and the construction of their relationship with the europeanization of public services. It will analyse the perspectives of a Community energy policy around three key questions: what internal market? What common policy? What public service obligations? (authors)

Energy systems analysis of biogas systems; Energianalys av biogassystem

Energy Technology Data Exchange (ETDEWEB)

Berglund, Maria; Boerjesson, Paal

2003-05-01

The aim of this study was to calculate the net energy output and energy efficiency, from a life-cycle perspective and for Swedish conditions, in anaerobic digestion of various raw materials. Our calculations are based on literature reviews concerning the total primary energy input required for the production of biogas (i.e. direct and indirect energy inputs, e.g. when producing and distributing diesel fuels, electricity, fertilisers) as well as the biogas yield from various raw materials. Our analyses include handling and transportation of raw materials, operation of the biogas plants, and transportation and spreading of digested residues, as well as the biogas yield from manure, ley crops, tops and leaves of sugar beets, straw, municipal organic waste, slaughter waste, and grease separator sludge. All calculations concern individual raw materials. The net energy input required to run a biogas system (i.e. centralised biogas plant) typically corresponds to approximately 20-40% of the energy content in the produced biogas. Theoretically, the raw materials could be transported for some 200 km (manure) up to 700 km (slaughter waste) before the net energy output becomes negative. The variations in energy efficiency between studied biogas systems depend mainly on the type of raw material studied and the calculation methods used. Raw materials with high water content and low biogas yield (e.g. manure) require rather large energy inputs compared to the amount of biogas produced. Energy demanding handling of the raw materials, such as ley crops, could correspond to as much as approximately 40% of the net energy input. Varying energy efficiency in different parts of the biogas system, but most of all, changes in the biogas yield, could considerably affect the total net energy output. In general, operation of the biogas plant is the most energy demanding process in the biogas systems, corresponding to some 40-80% of the net energy input in the biogas systems. This implies

Entropy, pumped-storage and energy system finance

Science.gov (United States)

Karakatsanis, Georgios

2015-04-01

Pumped-storage holds a key role for integrating renewable energy units with non-renewable fuel plants into large-scale energy systems of electricity output. An emerging issue is the development of financial engineering models with physical basis to systematically fund energy system efficiency improvements across its operation. A fundamental physically-based economic concept is the Scarcity Rent; which concerns the pricing of a natural resource's scarcity. Specifically, the scarcity rent comprises a fraction of a depleting resource's full price and accumulates to fund its more efficient future use. In an integrated energy system, scarcity rents derive from various resources and can be deposited to a pooled fund to finance the energy system's overall efficiency increase; allowing it to benefit from economies of scale. With pumped-storage incorporated to the system, water upgrades to a hub resource, in which the scarcity rents of all connected energy sources are denominated to. However, as available water for electricity generation or storage is also limited, a scarcity rent upon it is also imposed. It is suggested that scarcity rent generation is reducible to three (3) main factors, incorporating uncertainty: (1) water's natural renewability, (2) the energy system's intermittent components and (3) base-load prediction deviations from actual loads. For that purpose, the concept of entropy is used in order to measure the energy system's overall uncertainty; hence pumped-storage intensity requirements and generated water scarcity rents. Keywords: pumped-storage, integration, energy systems, financial engineering, physical basis, Scarcity Rent, pooled fund, economies of scale, hub resource, uncertainty, entropy Acknowledgement: This research was funded by the Greek General Secretariat for Research and Technology through the research project Combined REnewable Systems for Sustainable ENergy DevelOpment (CRESSENDO; grant number 5145)

The proton therapy system for Massachusetts General Hospital's Northeast Proton Therapy Center

International Nuclear Information System (INIS)

Jongen, Y.

1996-01-01

In 1989, two companies, Ion Beam Applications in Belgium (IBA) and Sumitomo Heavy Industries in Japan (SHI) started to design proton therapy equipments based on cyclotrons. In 1991, SHI and IBA decided to join their development efforts in this field. In 1993, the Massachusetts General Hospital (MGH), pioneer in the field of proton therapy, launched an international request for proposals for the procurement of an in-hospital proton therapy facility. The 18 may 1994, the contract was signed with a team of industries led by IBA, including also SHI and General Atomics (GA) of California. The proposed system is based on a fixed energy, isochronous cyclotron, followed by an energy degrader and an energy selection system. The variable energy beam can be rapidly switched in any one of three treatment rooms. Two rooms are equipped with large isocentric gantries and robotic patient positioners allowing to direct the proton beam within the patient from any direction. The third room is equipped with fixed horizontal beam. The complete system is computer controlled by a distributed network of computers, programmable logic controllers and workstations. This computer control allows to change the energy in one treatment room is less than two second, a performance matching or exceeding the flexibility offered by synchrotrons. The system is now built and undergoing factory tests. The beam has been accelerated to full energy in the cyclotron, and beam extraction tests are underway. Installation in the hospital building will take place in 1997. (author)

A systems approach to reduce urban rail energy consumption

International Nuclear Information System (INIS)

González-Gil, A.; Palacin, R.; Batty, P.; Powell, J.P.

2014-01-01

Highlights: • An insightful overview of energy usage in urban rail systems is given. • The principal measures to reduce urban rail energy consumption are appraised. • A methodology is proposed to help implement energy saving schemes in urban rail. • Regenerative braking is shown to offer the greatest energy saving potential. - Abstract: There is increasing interest in the potential of urban rail to reduce the impact of metropolitan transportation due to its high capacity, reliability and absence of local emissions. However, in a context characterised by increasing capacity demands and rising energy costs, and where other transport modes are considerably improving their environmental performance, urban rail must minimise its energy use without affecting its service quality. Urban rail energy consumption is defined by a wide range of interdependent factors; therefore, a system wide perspective is required, rather than focusing on energy savings at subsystem level. This paper contributes to the current literature by proposing an holistic approach to reduce the overall energy consumption of urban rail. Firstly, a general description of this transport mode is given, which includes an assessment of its typical energy breakdown. Secondly, a comprehensive appraisal of the main practices, strategies and technologies currently available to minimise its energy use is provided. These comprise: regenerative braking, energy-efficient driving, traction losses reduction, comfort functions optimisation, energy metering, smart power management and renewable energy micro-generation. Finally, a clear, logical methodology is described to optimally define and implement energy saving schemes in urban rail systems. This includes general guidelines for a qualitative assessment and comparison of measures alongside a discussion on the principal interdependences between them. As a hypothetical example of application, the paper concludes that the energy consumption in existing urban

Generalized Lorenz models and their routes to chaos. II. Energy-conserving horizontal mode truncations

International Nuclear Information System (INIS)

Roy, D.; Musielak, Z.E.

2007-01-01

All attempts to generalize the three-dimensional Lorenz model by selecting higher-order Fourier modes can be divided into three categories, namely: vertical, horizontal and vertical-horizontal mode truncations. The previous study showed that the first method allowed only construction of a nine-dimensional system when the selected modes were energy-conserving. The results presented in this paper demonstrate that a five-dimensional model is the lowest-order generalized Lorenz model that can be constructed by the second method and that its route to chaos is the same as that observed in the original Lorenz model. It is shown that the onset of chaos in both systems is determined by a number of modes that describe the vertical temperature difference in a convection roll. In addition, a simple rule that allows selecting modes that conserve energy for each method is derived

Energy-efficient fault tolerance in multiprocessor real-time systems

Science.gov (United States)

Guo, Yifeng

The recent progress in the multiprocessor/multicore systems has important implications for real-time system design and operation. From vehicle navigation to space applications as well as industrial control systems, the trend is to deploy multiple processors in real-time systems: systems with 4 -- 8 processors are common, and it is expected that many-core systems with dozens of processing cores will be available in near future. For such systems, in addition to general temporal requirement common for all real-time systems, two additional operational objectives are seen as critical: energy efficiency and fault tolerance. An intriguing dimension of the problem is that energy efficiency and fault tolerance are typically conflicting objectives, due to the fact that tolerating faults (e.g., permanent/transient) often requires extra resources with high energy consumption potential. In this dissertation, various techniques for energy-efficient fault tolerance in multiprocessor real-time systems have been investigated. First, the Reliability-Aware Power Management (RAPM) framework, which can preserve the system reliability with respect to transient faults when Dynamic Voltage Scaling (DVS) is applied for energy savings, is extended to support parallel real-time applications with precedence constraints. Next, the traditional Standby-Sparing (SS) technique for dual processor systems, which takes both transient and permanent faults into consideration while saving energy, is generalized to support multiprocessor systems with arbitrary number of identical processors. Observing the inefficient usage of slack time in the SS technique, a Preference-Oriented Scheduling Framework is designed to address the problem where tasks are given preferences for being executed as soon as possible (ASAP) or as late as possible (ALAP). A preference-oriented earliest deadline (POED) scheduler is proposed and its application in multiprocessor systems for energy-efficient fault tolerance is

Technology assessment of wind energy conversion systems

Energy Technology Data Exchange (ETDEWEB)

Meier, B. W.; Merson, T. J.

1980-09-01

Environmental data for wind energy conversion systems (WECSs) have been generated in support of the Technology Assessment of Solar Energy (TASE) program. Two candidates have been chosen to characterize the WECS that might be deployed if this technology makes a significant contribution to the national energy requirements. One WECS is a large machine of 1.5-MW-rated capacity that can be used by utilities. The other WECS is a small machine that is characteristic of units that might be used to meet residential or small business energy requirements. Energy storage systems are discussed for each machine to address the intermittent nature of wind power. Many types of WECSs are being studied and a brief review of the technology is included to give background for choosing horizontal axis designs for this study. Cost estimates have been made for both large and small systems as required for input to the Strategic Environmental Assessment Simulation (SEAS) computer program. Material requirements, based on current generation WECSs, are discussed and a general discussion of environmental impacts associated with WECS deployment is presented.

Sustainable energy systems: Limitations and challenges based on exergy analysis

OpenAIRE

Woudstra, N.

2012-01-01

General There is a general understanding that the so-called “developed countries” have to change their way of life including their energy supply into a more sustainable way. But even in the case of unanimity with regard to the direction, there are still many opinions about the way to follow. This thesis discusses problems and possibilities of more sustainable energy systems first of all for the energy supply of the Netherlands. The “trias energetica” is used to distinguish the steps that have...

Assessing District Energy Systems Performance Integrated with Multiple Thermal Energy Storages

Science.gov (United States)

Rezaie, Behnaz

The goal of this study is to examine various energy resources in district energy (DE) systems and then DE system performance development by means of multiple thermal energy storages (TES) application. This study sheds light on areas not yet investigated precisely in detail. Throughout the research, major components of the heat plant, energy suppliers of the DE systems, and TES characteristics are separately examined; integration of various configurations of the multiple TESs in the DE system is then analysed. In the first part of the study, various sources of energy are compared, in a consistent manner, financially and environmentally. The TES performance is then assessed from various aspects. Then, TES(s) and DE systems with several sources of energy are integrated, and are investigated as a heat process centre. The most efficient configurations of the multiple TESs integrated with the DE system are investigated. Some of the findings of this study are applied on an actual DE system. The outcomes of this study provide insight for researchers and engineers who work in this field, as well as policy makers and project managers who are decision-makers. The accomplishments of the study are original developments TESs and DE systems. As an original development the Enviro-Economic Function, to balance the economic and environmental aspects of energy resources technologies in DE systems, is developed; various configurations of multiple TESs, including series, parallel, and general grid, are developed. The developed related functions are discharge temperature and energy of the TES, and energy and exergy efficiencies of the TES. The TES charging and discharging behavior of TES instantaneously is also investigated to obtain the charging temperature, the maximum charging temperature, the charging energy flow, maximum heat flow capacity, the discharging temperature, the minimum charging temperature, the discharging energy flow, the maximum heat flow capacity, and performance

Parton self-energies for general momentum-space anisotropy

Science.gov (United States)

Kasmaei, Babak S.; Strickland, Michael

2018-03-01

We introduce an efficient general method for calculating the self-energies, collective modes, and dispersion relations of quarks and gluons in a momentum-anisotropic high-temperature quark-gluon plasma. The method introduced is applicable to the most general classes of deformed anisotropic momentum distributions and the resulting self-energies are expressed in terms of a series of hypergeometric basis functions which are valid in the entire complex phase-velocity plane. Comparing to direct numerical integration of the self-energies, the proposed method is orders of magnitude faster and provides results with similar or better accuracy. To extend previous studies and demonstrate the application of the proposed method, we present numerical results for the parton self-energies and dispersion relations of partonic collective excitations for the case of an ellipsoidal momentum-space anisotropy. Finally, we also present, for the first time, the gluon unstable mode growth rate for the case of an ellipsoidal momentum-space anisotropy.

Energy systems

Energy Technology Data Exchange (ETDEWEB)

Haefele, W [Nuclear Research Centre, Applied Systems Analysis and Reactor Physics, Karlsruhe (Germany); International Institute for Applied Systems Analysis, Laxenburg (Austria)

1974-07-01

Up to the present the production, transmission and distribution of energy has been considered mostly as a fragmented problem; at best only subsystems have been considered. Today the scale of energy utilization is increasing rapidly, and correspondingly, the reliance of societies on energy. Such strong quantitative increases influence the qualitative nature of energy utilization in most of its aspects. Resources, reserves, reliability and environment are among the key words that may characterize the change in the nature of the energy utilization problem. Energy can no longer be considered an isolated technical and economical problem, rather it is embedded in the ecosphere and the society-technology complex. Restraints and boundary conditions have to be taken into account with the same degree of attention as in traditional technical problems, for example a steam turbine. This results in a strong degree of interweaving. Further, the purpose of providing energy becomes more visible, that is, to make survival possible in a civilized and highly populated world on a finite globe. Because of such interweaving and finiteness it is felt that energy should be considered as a system and therefore the term 'energy systems' is used. The production of energy is only one component of such a system; the handling of energy and the embedding of energy into the global and social complex in terms of ecology, economy, risks and resources are of similar importance. he systems approach to the energy problem needs more explanation. This paper is meant to give an outline of the underlying problems and it is hoped that by so doing the wide range of sometimes confusing voices about energy can be better understood. Such confusion starts already with the term 'energy crisis'. Is there an energy crisis or not? Much future work is required to tackle the problems of energy systems. This paper can only marginally help in that respect. But it is hoped that it will help understand the scope of the

Energy systems

International Nuclear Information System (INIS)

Haefele, W.

1974-01-01

Up to the present the production, transmission and distribution of energy has been considered mostly as a fragmented problem; at best only subsystems have been considered. Today the scale of energy utilization is increasing rapidly, and correspondingly, the reliance of societies on energy. Such strong quantitative increases influence the qualitative nature of energy utilization in most of its aspects. Resources, reserves, reliability and environment are among the key words that may characterize the change in the nature of the energy utilization problem. Energy can no longer be considered an isolated technical and economical problem, rather it is embedded in the ecosphere and the society-technology complex. Restraints and boundary conditions have to be taken into account with the same degree of attention as in traditional technical problems, for example a steam turbine. This results in a strong degree of interweaving. Further, the purpose of providing energy becomes more visible, that is, to make survival possible in a civilized and highly populated world on a finite globe. Because of such interweaving and finiteness it is felt that energy should be considered as a system and therefore the term 'energy systems' is used. The production of energy is only one component of such a system; the handling of energy and the embedding of energy into the global and social complex in terms of ecology, economy, risks and resources are of similar importance. he systems approach to the energy problem needs more explanation. This paper is meant to give an outline of the underlying problems and it is hoped that by so doing the wide range of sometimes confusing voices about energy can be better understood. Such confusion starts already with the term 'energy crisis'. Is there an energy crisis or not? Much future work is required to tackle the problems of energy systems. This paper can only marginally help in that respect. But it is hoped that it will help understand the scope of the

A System of Systems (SoS) Approach to Sustainable Energy Planning

Science.gov (United States)

Madani, Kaveh; Hadian, Saeed

2015-04-01

The general policy of mandating fossil fuel replacement with "green" energies may not be as effective and environmental-friendly as perceived, due to the secondary impacts of renewable energies on different natural resources. An integrated systems analysis framework is essential to developing sustainable energy supply systems with minimal unintended impacts on valuable natural resources such as water, climate, and ecosystem. This presentation discusses how a system of systems (SoS) framework can be developed to quantitatively evaluate the desirability of different energy supply alternatives with respect to different sustainability criteria under uncertainty. Relative Aggregate Footprint (RAF) scores of a range of renewable and nonrenewable energy alternatives are determined using their performance values under four sustainability criteria, namely carbon footprint, water footprint, land footprint, and cost of energy production. Our results suggest that despite their lower emissions, some renewable energy sources are less promising than non-renewable energy sources from a SoS perspective that considers the trade-offs between carbon footprint of energies and their effects on water, ecosystem, and economic resources. A new framework based on the Modern Portfolio Theory (MPT) is also proposed for analyzing the overall sustainability of different energy mixes for different risk of return levels with respect to the trade-offs involved. It is discussed how the proposed finance-based sustainability evaluation method can help policy makers maximize the energy portfolio's expected sustainability for a given amount of portfolio risk, or equivalently minimize risk for a given level of expected sustainability level, by revising the energy mix.

Preliminary Findings from an Analysis of Building Energy Information System Technologies

Energy Technology Data Exchange (ETDEWEB)

Granderson, Jessica; Piette, Mary Ann; Ghatikar, Girish; Price, Philip

2009-06-01

Energy information systems comprise software, data acquisition hardware, and communication systems that are intended to provide energy information to building energy and facilities managers, financial managers, and utilities. This technology has been commercially available for over a decade, however recent advances in Internet and other information technology, and analytical features have expanded the number of product options that are available. For example, features such as green house gas tracking, configurable energy analyses and enhanced interoperability are becoming increasingly common. Energy information systems are used in a variety of commercial buildings operations and environments, and can be characterized in a number of ways. Basic elements of these systems include web-based energy monitoring, web-based energy management linked to controls, demand response, and enterprise energy management applications. However the sheer number and variety of available systems complicate the selection of products to match the needs of a given user. In response, a framework was developed to define the capabilities of different types of energy information systems, and was applied to characterize approximately 30 technologies. Measurement is a critical component in managing energy consumption and energy information must be shared at all organizational levels to maintain persistent, efficient operations. Energy information systems are important to understand because they offer the analytical support to process measured data into information, and they provide the informational link between the primary actors who impact building energy efficiency - operators, facilities and energy managers, owners and corporate decision makers. In this paper, preliminary findings are presented, with a focus on overall trends and the general state of the technology. Key conclusions include the need to further pursue standardization and usability, x-y plotting as an under-supported feature, and

Wind energy systems

Science.gov (United States)

Stewart, H. J.

1978-01-01

A discussion on wind energy systems involved with the DOE wind energy program is presented. Some of the problems associated with wind energy systems are discussed. The cost, efficiency, and structural design of wind energy systems are analyzed.

Energy management system for power distribution. Interfaces and data communication requirements

International Nuclear Information System (INIS)

Koponen, P.; Lemstroem, B.; Ikonen, J.

1995-01-01

The opening of the electricity market for competition in Finland creates new requirements for the information systems and data communication in distribution utilities. Energy management systems for distribution utilities are needed with interfaces that make it possible to separate the network business from the energy trade business. However, these interfaces should also support optimization of the whole energy supply system of the country. In this report the interfaces and data communication requirements of the energy management system of the electricity trade business are analyzed. To support this subfunctions of the energy management have been analyzed. It was realized that the amount of necessary data transfer and optimization of the national power system both depend strongly on the general rules of the energy markets. (author)

DNA - A Thermal Energy System Simulator

DEFF Research Database (Denmark)

2008-01-01

DNA is a general energy system simulator for both steady-state and dynamic simulation. The program includes a * component model library * thermodynamic state models for fluids and solid fuels and * standard numerical solvers for differential and algebraic equation systems and is free and portable...... (open source, open use, standard FORTRAN77). DNA is text-based using whichever editor, you like best. It has been integerated with the emacs editor. This is usually available on unix-like systems. for windows we recommend the Installation instructions for windows: First install emacs and then run...... the DNA installer...

Energy-Water System Solutions | Energy Analysis | NREL

Science.gov (United States)

System Solutions Energy-Water System Solutions NREL has been a pioneer in the development of energy -water system solutions that explicitly address and optimize energy-water tradeoffs. NREL has evaluated energy-water system solutions for Department of Defense bases, islands, communities recovering from

Algebraic structure of general electromagnetic fields and energy flow

International Nuclear Information System (INIS)

Hacyan, Shahen

2011-01-01

Highlights: → Algebraic structure of general electromagnetic fields in stationary spacetime. → Eigenvalues and eigenvectors of the electomagnetic field tensor. → Energy-momentum in terms of eigenvectors and Killing vector. → Explicit form of reference frame with vanishing Poynting vector. → Application of formalism to Bessel beams. - Abstract: The algebraic structures of a general electromagnetic field and its energy-momentum tensor in a stationary space-time are analyzed. The explicit form of the reference frame in which the energy of the field appears at rest is obtained in terms of the eigenvectors of the electromagnetic tensor and the existing Killing vector. The case of a stationary electromagnetic field is also studied and a comparison is made with the standard short-wave approximation. The results can be applied to the general case of a structured light beams, in flat or curved spaces. Bessel beams are worked out as example.

Renewable Energy Systems

DEFF Research Database (Denmark)

Lund, Henrik; Mathiesen, Brian Vad; Connolly, David

2014-01-01

on the electricity sector, smart energy systems include the entire energy system in its approach to identifying suitable energy infrastructure designs and operation strategies. The typical smart grid sole focus on the electricity sector often leads to the conclusion that transmission lines, flexible electricity......This paper presents the learning of a series of studies that analyse the problems and perspectives of converting the present energy system into a 100 % renewable energy system using a smart energy systems approach. As opposed to, for instance, the smart grid concept, which takes a sole focus...... are to be found when the electricity sector is combined with the heating and cooling sectors and/or the transportation sector. Moreover, the combination of electricity and gas infrastructures may play an important role in the design of future renewable energy systems. The paper illustrates why electricity smart...

Studies on energy system for an energy-saving society; Sho energy gata shakai ni okeru energy system kento

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-03-01

The system to which new energy technology and energy saving technology were introduced was constructed for case studies of urban areas including core cities and the peripheral areas, and the quantitative analysis was conducted on environmental effects, etc. In the energy supply system model, the following element technologies were all considered: cogeneration system, sewage water heat, river water heat, the photovoltaic power generation, energy storage/heat storage/cold heat storage, adsorption type refrigerator, etc. Also considered were power interchange between clusters, system power buying/power selling, heat interchange or no heat interchange, etc. As a result, it was found that when constructing the energy system which synthetically takes into account thermoelectric ratios, rates of simultaneous loads, ratios of daytime/nighttime in the energy supply and demand in the urban area, the energy saving effect multiplicatively increases, and the energy system using cogeneration and unused energy such as refuse and sewage in the urban area and river water brings an energy saving effect of 32% especially in the concentrated cluster. 83 figs., 45 tabs.

Energy saving synergies in national energy systems

DEFF Research Database (Denmark)

Thellufsen, Jakob Zinck; Lund, Henrik

2015-01-01

In the transition towards a 100% renewable energy system, energy savings are essential. The possibility of energy savings through conservation or efficiency increases can be identified in, for instance, the heating and electricity sectors, in industry, and in transport. Several studies point...... to various optimal levels of savings in the different sectors of the energy system. However, these studies do not investigate the idea of energy savings being system dependent. This paper argues that such system dependency is critical to understand, as it does not make sense to analyse an energy saving...... without taking into account the actual benefit of the saving in relation to the energy system. The study therefore identifies a need to understand how saving methods may interact with each other and the system in which they are conducted. By using energy system analysis to do hourly simulation...

Advances in energy systems and technology v.5

CERN Document Server

Auer, Peter L

1986-01-01

Advances in Energy Systems and Technology: Volume 5 present articles that provides a critical review of specific topics within the general field of energy. It discusses the fuel cells for electric utility power generation. It addresses the classification of fuel cell technologies. Some of the topics covered in the book are the major components of the fuel cell; the phosphoric acid fuel cells; molten carbonate fuel cells; solid oxide fuel cells; electric utility fuel cell systems; and the integration within fuel cell power plants. The analysis of the solar ponds is covered. The operational

Generalized Gibbs distribution and energy localization in the semiclassical FPU problem

Science.gov (United States)

Hipolito, Rafael; Danshita, Ippei; Oganesyan, Vadim; Polkovnikov, Anatoli

2011-03-01

We investigate dynamics of the weakly interacting quantum mechanical Fermi-Pasta-Ulam (qFPU) model in the semiclassical limit below the stochasticity threshold. Within this limit we find that initial quantum fluctuations lead to the damping of FPU oscillations and relaxation of the system to a slowly evolving steady state with energy localized within few momentum modes. We find that in large systems this state can be described by the generalized Gibbs ensemble (GGE), with the Lagrange multipliers being very weak functions of time. This ensembles gives accurate description of the instantaneous correlation functions, both quadratic and quartic. Based on these results we conjecture that GGE generically appears as a prethermalized state in weakly non-integrable systems.

Energy Storage and Smart Energy Systems

DEFF Research Database (Denmark)

Lund, Henrik; Østergaard, Poul Alberg; Connolly, David

2016-01-01

It is often highlighted how the transition to renewable energy supply calls for significant electricity storage. However, one has to move beyond the electricity-only focus and take a holistic energy system view to identify optimal solutions for integrating renewable energy. In this paper......, an integrated cross-sector approach is used to determine the most efficient and least-cost storage options for the entire renewable energy system concluding that the best storage solutions cannot be found through analyses focusing on the individual sub-sectors. Electricity storage is not the optimum solution...... to integrate large inflows of fluctuating renewable energy, since more efficient and cheaper options can be found by integrating the electricity sector with other parts of the energy system and by this creating a Smart Energy System. Nevertheless, this does not imply that electricity storage should...

A normative price for energy from an electricity generation system: An Owner-dependent Methodology for Energy Generation (system) Assessment (OMEGA). Volume 1: Summary

Science.gov (United States)

Chamberlain, R. G.; McMaster, K. M.

1981-10-01

The utility owned solar electric system methodology is generalized and updated. The net present value of the system is determined by consideration of all financial benefits and costs (including a specified return on investment). Life cycle costs, life cycle revenues, and residual system values are obtained. Break even values of system parameters are estimated by setting the net present value to zero. While the model was designed for photovoltaic generators with a possible thermal energy byproduct, it applicability is not limited to such systems. The resulting owner-dependent methodology for energy generation system assessment consists of a few equations that can be evaluated without the aid of a high-speed computer.

A normative price for energy from an electricity generation system: An Owner-dependent Methodology for Energy Generation (system) Assessment (OMEGA). Volume 1: Summary

Science.gov (United States)

Chamberlain, R. G.; Mcmaster, K. M.

1981-01-01

The utility owned solar electric system methodology is generalized and updated. The net present value of the system is determined by consideration of all financial benefits and costs (including a specified return on investment). Life cycle costs, life cycle revenues, and residual system values are obtained. Break even values of system parameters are estimated by setting the net present value to zero. While the model was designed for photovoltaic generators with a possible thermal energy byproduct, it applicability is not limited to such systems. The resulting owner-dependent methodology for energy generation system assessment consists of a few equations that can be evaluated without the aid of a high-speed computer.

General solar energy information user study

Energy Technology Data Exchange (ETDEWEB)

Belew, W.W.; Wood, B.L.; Marle, T.L.; Reinhardt, C.L.

1981-03-01

This report describes the results of a series of telephone interviews with groups of users of information on general solar energy. These results, part of a larger study on many different solar technologies, identify types of information each group needed and the best ways to get information to each group. The report is 1 of 10 discussing study results. The overall study provides baseline data about information needs in the solar community. An earlier study identified the information user groups in the solar community and the priority (to accelerate solar energy commercialization) of getting information to each group. In the current study only high-priority groups were examined. Results from 13 groups of respondents are analyzed in this report: Loan Officers, Real Estate Appraisers, Tax Assessors, Insurers, Lawyers, Utility Representatives, Public Interest Group Representatives, Information and Agricultural Representatives, Public Interest Group Representatives, Information and Agricultural Specialists at State Cooperative Extension Service Offices, and State Energy Office Representatives. The data will be used as input to the determination of information products and services the Solar Energy Research Institute, the Solar Energy Information Data Bank Network, and the entire information outreach community should be preparing and disseminating.

Improved production operating efficiencies through automation: Wascana Energy`s SCADA system implementation in southeast Saskatchewan

Energy Technology Data Exchange (ETDEWEB)

Knudsen, R; Foord, T; Bartle, A

1996-12-31

Supervisory control and data acquisition (SCADA) systems covering Wascana Energy`s whole southeast Saskatchewan operating area were implemented in 1994-95. The benefits of this automation were described. Operations practices were reviewed and a brief description of the system was provided. Main features of the system described included data storage/retrieval, data display, alarm group organization, alarm call out monitoring, dynagraph display, and the Microsoft SQL server computer. Automation was found to significantly change the operator`s traditional role and altered operation practices in general. SCADA systems were found to improve operating efficiencies and production performance significantly, when properly implemented and utilized. 6 refs., 3 figs.

Energy systems security

CERN Document Server

Voeller, John G

2014-01-01

Energy Systems Security features articles from the Wiley Handbook of Science and Technology for Homeland Security covering topics related to electricity transmission grids and their protection, risk assessment of energy systems, analysis of interdependent energy networks. Methods to manage electricity transmission disturbances so as to avoid blackouts are discussed, and self-healing energy system and a nano-enabled power source are presented.

Photovoltaic Energy Harvester with Power Management System

Directory of Open Access Journals (Sweden)

M. Ferri

2010-01-01

Full Text Available We present a photovoltaic energy harvester, realized in 0.35-μm CMOS technology. The proposed system collects light energy from the environment, by means of 2-mm2 on-chip integrated microsolar cells, and accumulates it in an external capacitor. While the capacitor is charging, the load is disconnected. When the energy in the external capacitor is enough to operate the load for a predefined time slot, the load is connected to the capacitor by a power management circuit. The choice of the value of the capacitance determines the operating time slot for the load. The proposed solution is suitable for discrete-time-regime applications, such as sensor network nodes, or, in general, systems that require power supply periodically for short time slots. The power management circuit includes a charge pump, a comparator, a level shifter, and a linear voltage regulator. The whole system has been extensively simulated, integrated, and experimentally characterized.

The energy efficiency partnership - Kraft General Foods and Boston Edison Company

International Nuclear Information System (INIS)

Crowley, J.C.; Donoghue, J.P.

1993-01-01

During the past twenty years, inordinate shifts in the supply and demand of energy have forced both electric utility companies and their customers to investigate new and innovative ways to satisfy the ever increasing demand for electricity. The Energy Efficiency Partnership, developed between Kraft General Foods and Boston Edison Company, presents an exemplary study of how two corporate giants creatively solved the problem of uncontrolled energy costs and its positive effect on the overall operations of Kraft General Foods, Framingham. But the Energy Efficiency Partnership did more than reduce energy costs, it provided benefits to all parties on the playing field. To understand its significance, a review of the partnership's history is paramount. The first official announcement of the Energy Efficiency Partnership was made on April 9, 1990. Framingham, MA, The Commonwealth of Massachusetts Kraft General Foods Framingham, and Boston Edison Company have joined forces in a $3.6 million dollar energy partnership that will help keep 250 industrial jobs in Massachusetts and could lead to the future expansion of the international food company's Framingham facility

Energy Storage and Smart Energy Systems

Directory of Open Access Journals (Sweden)

Poul Alberg Østergaard

2016-12-01

Full Text Available It is often highlighted how the transition to renewable energy supply calls for significant electricity storage. However, one has to move beyond the electricity-only focus and take a holistic energy system view to identify optimal solutions for integrating renewable energy. In this paper, an integrated cross-sector approach is used to determine the most efficient and least-cost storage options for the entire renewable energy system concluding that the best storage solutions cannot be found through analyses focusing on the individual sub-sectors. Electricity storage is not the optimum solution to integrate large inflows of fluctuating renewable energy, since more efficient and cheaper options can be found by integrating the electricity sector with other parts of the energy system and by this creating a Smart Energy System. Nevertheless, this does not imply that electricity storage should be disregarded but that it will be needed for other purposes in the future.

Energy savings potential from energy-conserving irrigation systems

Energy Technology Data Exchange (ETDEWEB)

Wilfert, G.L.; Patton, W.P.; Harrer, B.J.; Clark, M.A.

1982-11-01

This report systematically compares, within a consistent framework, the technical and economic characteristics of energy-conserving irrigation systems with those of conventional irrigation systems and to determine total energy savings. Levelized annual costs of owning and operating both energy-conserving and conventional irrigation systems have been developed and compared for all 17 states to account for the differences in energy costs and irrigation conditions in each state. Market penetration of energy-conserving systems is assessed for those systems having lower levelized annual costs than conventional systems performing the same function. Annual energy savings were computed by matching the energy savings per system with an assumed maximum market penetration of 100 percent in those markets where the levelized annual costs of energy-conserving systems are lower than the levelized annual costs of conventional systems.

21st century's energy: hydrogen energy system

International Nuclear Information System (INIS)

Veziroglu, T. N.

2007-01-01

Fossil fuels (i.e., petroleum, natural gas and coal), which meet most of the world's energy demand today, are being depleted fast. Also, their combustion products are causing the global problems, such as the greenhouse effect, ozone layer depletion, acid rains and pollution, which are posing great danger for our environment and eventually for the life in our planet. Many engineers and scientists agree that the solution to these global problems would be to replace the existing fossil fuel system by the Hydrogen Energy System. Hydrogen is a very efficient and clean fuel. Its combustion will produce no greenhouse gases, no ozone layer depleting chemicals, little or no acid rain ingredients and pollution. Hydrogen, produced from renewable energy (e.g., solar) sources, would result in a permanent energy system, which we would never have to change. However, there are other energy systems proposed for the post-petroleum era, such as a synthetic fossil fuel system. In this system, synthetic gasoline and synthetic natural gas will be produced using abundant deposits of coal. In a way, this will ensure the continuation of the present fossil fuel system. The two possible energy systems for the post-fossil fuel era (i.e., the solar hydrogen energy system and the synthetic fossil fuel system) are compared with the present fossil fuel system by taking into consideration production costs, environmental damages and utilization efficiencies. The results indicate that the solar hydrogen energy system is the best energy system to ascertain a sustainable future, and it should replace the fossil fuel system before the end of the 21st Century

21st Century's energy: Hydrogen energy system

International Nuclear Information System (INIS)

Veziroglu, T. Nejat; Sahin, Suemer

2008-01-01

Fossil fuels (i.e., petroleum, natural gas and coal), which meet most of the world's energy demand today, are being depleted fast. Also, their combustion products are causing the global problems, such as the greenhouse effect, ozone layer depletion, acid rains and pollution, which are posing great danger for our environment and eventually for the life in our planet. Many engineers and scientists agree that the solution to these global problems would be to replace the existing fossil fuel system by the hydrogen energy system. Hydrogen is a very efficient and clean fuel. Its combustion will produce no greenhouse gases, no ozone layer depleting chemicals, little or no acid rain ingredients and pollution. Hydrogen, produced from renewable energy (e.g., solar) sources, would result in a permanent energy system, which we would never have to change. However, there are other energy systems proposed for the post-petroleum era, such as a synthetic fossil fuel system. In this system, synthetic gasoline and synthetic natural gas will be produced using abundant deposits of coal. In a way, this will ensure the continuation of the present fossil fuel system. The two possible energy systems for the post-fossil fuel era (i.e., the solar-hydrogen energy system and the synthetic fossil fuel system) are compared with the present fossil fuel system by taking into consideration production costs, environmental damages and utilization efficiencies. The results indicate that the solar-hydrogen energy system is the best energy system to ascertain a sustainable future, and it should replace the fossil fuel system before the end of the 21st century

Background history and cosmic perturbations for a general system of self-conserved dynamical dark energy and matter

International Nuclear Information System (INIS)

Gómez-Valent, Adrià; Karimkhani, Elahe; Solà, Joan

2015-01-01

We determine the Hubble expansion and the general cosmic perturbation equations for a general system consisting of self-conserved matter, ρ m , and self-conserved dark energy (DE), ρ D . While at the background level the two components are non-interacting, they do interact at the perturbations level. We show that the coupled system of matter and DE perturbations can be transformed into a single, third order, matter perturbation equation, which reduces to the (derivative of the) standard one in the case that the DE is just a cosmological constant. As a nontrivial application we analyze a class of dynamical models whose DE density ρ D (H) consists of a constant term, C 0 , and a series of powers of the Hubble rate. These models were previously analyzed from the point of view of dynamical vacuum models, but here we treat them as self-conserved DE models with a dynamical equation of state. We fit them to the wealth of expansion history and linear structure formation data and compare their fit quality with that of the concordance ΛCDM model. Those with C 0 =0 include the so-called ''entropic-force'' and ''QCD-ghost'' DE models, as well as the pure linear model ρ D ∼H, all of which appear strongly disfavored. The models with C 0 ≠0 , in contrast, emerge as promising dynamical DE candidates whose phenomenological performance is highly competitive with the rigid Λ-term inherent to the ΛCDM

Background history and cosmic perturbations for a general system of self-conserved dynamical dark energy and matter

Energy Technology Data Exchange (ETDEWEB)

Gómez-Valent, Adrià; Karimkhani, Elahe; Solà, Joan, E-mail: adriagova@ecm.ub.edu, E-mail: e.karimkhani91@basu.ac.ir, E-mail: sola@ecm.ub.edu [High Energy Physics Group, Dept. ECM, and Institut de Ciències del Cosmos (ICC), Universitat de Barcelona, Av. Diagonal 647, E-08028 Barcelona, Catalonia (Spain)

2015-12-01

We determine the Hubble expansion and the general cosmic perturbation equations for a general system consisting of self-conserved matter, ρ{sub m}, and self-conserved dark energy (DE), ρ{sub D}. While at the background level the two components are non-interacting, they do interact at the perturbations level. We show that the coupled system of matter and DE perturbations can be transformed into a single, third order, matter perturbation equation, which reduces to the (derivative of the) standard one in the case that the DE is just a cosmological constant. As a nontrivial application we analyze a class of dynamical models whose DE density ρ{sub D}(H) consists of a constant term, C{sub 0}, and a series of powers of the Hubble rate. These models were previously analyzed from the point of view of dynamical vacuum models, but here we treat them as self-conserved DE models with a dynamical equation of state. We fit them to the wealth of expansion history and linear structure formation data and compare their fit quality with that of the concordance ΛCDM model. Those with C{sub 0}=0 include the so-called ''entropic-force'' and ''QCD-ghost'' DE models, as well as the pure linear model ρ{sub D}∼H, all of which appear strongly disfavored. The models with C{sub 0}≠0 , in contrast, emerge as promising dynamical DE candidates whose phenomenological performance is highly competitive with the rigid Λ-term inherent to the ΛCDM.

Generalized-stacking-fault energy and twin-boundary energy of hexagonal close-packed Au: A first-principles calculation.

Science.gov (United States)

Wang, Cheng; Wang, Huiyuan; Huang, Tianlong; Xue, Xuena; Qiu, Feng; Jiang, Qichuan

2015-05-22

Although solid Au is usually most stable as a face-centered cubic (fcc) structure, pure hexagonal close-packed (hcp) Au has been successfully fabricated recently. However, the phase stability and mechanical property of this new material are unclear, which may restrict its further applications. Here we present the evidence that hcp → fcc phase transformation can proceed easily in Au by first-principles calculations. The extremely low generalized-stacking-fault (GSF) energy in the basal slip system implies a great tendency to form basal stacking faults, which opens the door to phase transformation from hcp to fcc. Moreover, the Au lattice extends slightly within the superficial layers due to the self-assembly of alkanethiolate species on hcp Au (0001) surface, which may also contribute to the hcp → fcc phase transformation. Compared with hcp Mg, the GSF energies for non-basal slip systems and the twin-boundary (TB) energies for and twins are larger in hcp Au, which indicates the more difficulty in generating non-basal stacking faults and twins. The findings provide new insights for understanding the nature of the hcp → fcc phase transformation and guide the experiments of fabricating and developing materials with new structures.

NHIES: Energy systems in the period of transition

International Nuclear Information System (INIS)

Haefele, W.; Walbeck, M.; Martinsen, D.; Bundschuh, V.

1990-01-01

The concept of Novel Horizontally Integrated Energy Systems (NHIES), which assigns a decisive role to nuclear process heat generation, is explained in this chapter. The survey includes a system analysis and an outline of NHIES computed scenarios and models. The competitiveness of NHIES technology, its integration into the MARNES model as well as general and fundamental considerations and scenarios are discussed. (DG) [de

Non-existence of global solutions to generalized dissipative Klein-Gordon equations with positive energy

Directory of Open Access Journals (Sweden)

Maxim Olegovich Korpusov

2012-07-01

Full Text Available In this article the initial-boundary-value problem for generalized dissipative high-order equation of Klein-Gordon type is considered. We continue our study of nonlinear hyperbolic equations and systems with arbitrary positive energy. The modified concavity method by Levine is used for proving blow-up of solutions.

Concept research on general passive system

International Nuclear Information System (INIS)

Han Xu; Yang Yanhua; Zheng Mingguang

2009-01-01

This paper summarized the current passive techniques used in nuclear power plants. Through classification and analysis, the functional characteristics and inherent identification of passive systems were elucidated. By improving and extending the concept of passive system, the general passive concept was proposed, and space and time relativity was discussed and assumption of general passive system were illustrated. The function of idealized general passive system is equivalent with the current passive system, but the design of idealized general passive system is more flexible. (authors)

A novel multimode hybrid energy storage system and its energy management strategy for electric vehicles

Science.gov (United States)

Wang, Bin; Xu, Jun; Cao, Binggang; Zhou, Xuan

2015-05-01

This paper proposes a novel topology of multimode hybrid energy storage system (HESS) and its energy management strategy for electric vehicles (EVs). Compared to the conventional HESS, the proposed multimode HESS has more operating modes and thus it could in further enhance the efficiency of the system. The rule-based control strategy and the power-balancing strategy are developed for the energy management strategy to realize mode selection and power distribution. Generally, the DC-DC converter will operate at peak efficiency to convey the energy from the batteries to the UCs. Otherwise, the pure battery mode or the pure ultracapacitors (UCs) mode will be utilized without the DC-DC converter. To extend the battery life, the UCs have the highest priority to recycle the energy and the batteries are isolated from being recharged directly during regenerative braking. Simulations and experiments are established to validate the proposed multimode HESS and its energy management strategy. The results reveal that the energy losses in the DC-DC converter, the total energy consumption and the overall system efficiency of the proposed multimode HESS are improved compared to the conventional HESS.

Energy Systems Integration News | Energy Systems Integration Facility |

Science.gov (United States)

, utilities can operate more efficiently and profitably. That can increase the use of renewable energy sources challenge to utility companies, grid operators, and other stakeholders involved in wind energy integration recording is available from the July 16 webinar "Smart Grid Research at NREL's Energy Systems

Efficiency analysis of a cogeneration and district energy system

International Nuclear Information System (INIS)

Rosen, Marc A.; Le, Minh N.; Dincer, Ibrahim

2005-01-01

This paper presents an efficiency analysis, accounting for both energy and exergy considerations, of a design for a cogeneration-based district energy system. A case study is considered for the city of Edmonton, Canada, by the utility Edmonton Power. The original concept using central electric chillers, as well as two variations (one considering single-effect and the other double-effect absorption chillers) are examined. The energy- and exergy-based results differ markedly (e.g., overall energy efficiencies are shown to vary for the three configurations considered from 83% to 94%, and exergy efficiencies from 28% to 29%, respectively). For the overall processes, as well as individual subprocesses and selected combinations of subprocesses, the exergy efficiencies are generally found to be more meaningful and indicative of system behaviour than the energy efficiencies

Energy Systems Integration News - October 2016 | Energy Systems Integration

Science.gov (United States)

Facility | NREL October 2016 Energy Systems Integration News A monthly recap of the latest energy systems integration (ESI) developments at NREL and around the world. Subscribe Archives October Integration Facility's main control room. OMNETRIC Group Demonstrates a Distributed Control Hierarchy for

Energy efficient cross layer design for spectrum sharing systems

KAUST Repository

Alabbasi, Abdulrahman

2016-10-06

We propose a cross layer design that optimizes the energy efficiency of spectrum sharing systems. The energy per good bit (EPG) is considered as an energy efficiency metric. We optimize the secondary user\\'s transmission power and media access frame length to minimize the EPG metric. We protect the primary user transmission via an outage probability constraint. The non-convex targeted problem is optimized by utilizing the generalized convexity theory and verifying the strictly pseudo-convex structure of the problem. Analytical results of the optimal power and frame length are derived. We also used these results in proposing an algorithm, which guarantees the existence of a global optimal solution. Selected numerical results show the improvement of the proposed system compared to other systems. © 2016 IEEE.

Annual report 2005 General Direction of the Energy and raw materials; Rapport annuel 2005 Direction Generale de L'Energie et des Matieres Premieres

Energy Technology Data Exchange (ETDEWEB)

NONE

2005-07-01

This 2005 annual report of the DGEMP (General Direction of the Energy and the raw Materials), takes stock on the energy bill and accounting of the France. The first part presents the electric power, natural gas and raw materials market in France. The second part is devoted to the diversification of the energy resources with a special attention to the renewable energies and the nuclear energy. The third part discusses the energy and raw materials prices and the last part presents the international cooperation in the energy domain. (A.L.B.)

Potential energy consumption reduction of automotive climate control systems

International Nuclear Information System (INIS)

Nielsen, Filip; Uddheim, Åsa; Dalenbäck, Jan-Olof

2016-01-01

Highlights: • Twenty-on energy saving measures for vehicle interior climate were evaluated. • Few single energy saving measures could reduce the energy use significantly. • The operation of the system in intermediate conditions determines the energy use. • Required heating/cooling of passenger compartment had small effect on energy use. - Abstract: In recent years fuel consumption of passenger vehicles has received increased attention by customers, the automotive industry, regulatory agencies and academia. One area which affect the fuel consumption is climate control systems. Twenty-one energy saving measures were evaluated regarding the total energy use for vehicle interior climate using simulation. Evaluated properties were heat flow into the passenger compartment, electrical and mechanical work. The simulation model included sub models of the passenger compartment, air-handling unit, Air Conditioning (AC) system, engine and engine cooling system. A real-world representative test cycle, which included tests in cold, intermediate and warm conditions, was used for evaluation. In general, few single energy saving measures could reduce the energy use significantly. The measures with most potential were increased blower efficiency with a reduction of 46% of the electrical work and increased AC-system disengage temperature with a reduction of 27% of the mechanical work. These results show that the operation of the climate control system had a large effect on the energy use, especially compared to the required heating and cooling of the passenger compartment. As a result energy saving measures need to address how heating and cooling is generated before reducing the heat flow into the passenger compartment.

Energy policy of the International Energy Agency (IEA) countries. General review of the year 1990

International Nuclear Information System (INIS)

1992-01-01

This book is a general review on energy policy leaded by Members countries of International Energy Agency (IEA) during the year 1990. This book describes also the trends and the recent events which have affected energy demand, energy conservation, energy efficiency, energy supply and energy source development. This annual review gives the IEA energy forecasting for the next years, till year 2001. A detailed study of energy policy in Federal Republic of Germany, Austria, Denmark, Greece, Ireland and Japan is given. The policy of fifteen another Members countries, which have been analyzed the previous years, is recapitulated and briefly brought up to date

Three-body Coulomb systems using generalized angular-momentum S states

Science.gov (United States)

Whitten, R. C.; Sims, J. S.

1974-01-01

An expansion of the three-body Coulomb potential in generalized angular-momentum eigenfunctions developed earlier by one of the authors is used to compute energy eigenvalues and eigenfunctions of bound S states of three-body Coulomb systems. The results for He, H(-), e(-)e(+)e(-), and pmu(-)p are compared with the results of other computational approaches.

General Merchandise 50% Energy Savings Technical Support Document

Energy Technology Data Exchange (ETDEWEB)

Hale, E.; Leach, M.; Hirsch, A.; Torcellini, P.

2009-09-01

This report documents technical analysis for medium-box general merchandise stores aimed at providing design guidance that achieves whole-building energy savings of at least 50% over ASHRAE Standard 90.1-2004.

Commercial Building Partnership General Merchandise Energy Savings Overview

Energy Technology Data Exchange (ETDEWEB)

None

2013-03-01

The Commercial Building Partnership (CBP) paired selected commercial building owners and operators with representatives of DOE, national laboratories and private sector exports to explore energy efficiency measures across general merchandise commercial buildings.

The challenge of greening energy systems

International Nuclear Information System (INIS)

Joseph, A.; Hughes, L.

2006-01-01

The current state of world energy supply and demand was examined along with future challenges facing population growth, economic growth, energy-demand growth, fossil energy supply, technology improvements, renewable energy solutions, and conservation measures. It was suggested that in order to implement cleaner and greener energy technology, it is important to understand the nature of global energy systems. The challenge of defining the related ideologies of green energy and sustainability was discussed. In this paper, green energy was defined as indicating environmental compatibility with little or no negative environmental impact. This differs from the concept of sustainability, which was defined as an action that can be repeated continuously without depleting or diminishing resources. In general, green energy options include most technologies that do not involve fossil fuels. However, this paper considered a spectrum of shades of green with some options being low-impact and cleaner, and others having high environmental impacts. As an example, the authors presented the ongoing debate over nuclear energy and hydro power. Although both energy sources can be sustainable over hundreds of years, they may or may not be environmentally compatible because they are often considered to have problematic attributes. Energy from renewable sources currently accounts for less than 20 per cent of world primary energy supply because price and implementation challenges in the renewables sector do not generally compare well to other energy sources. With high energy-demands beginning to strain finite fossil-energy supplies, the energy sector is now subject to more frequent disruptions and price fluctuations. Future growth from emerging economies will demand more energy and resources. This paper also emphasized that the proportion of green sources of energy has not increased substantially in the past 3 decades, and despite many technological advances, there continue to be significant

The challenge of greening energy systems

Energy Technology Data Exchange (ETDEWEB)

Joseph, A.; Hughes, L. [Dalhousie Univ., Halifax, NS (Canada). Dept. of Electrical and Computer Engineering, Energy Research Group

2006-07-01

The current state of world energy supply and demand was examined along with future challenges facing population growth, economic growth, energy-demand growth, fossil energy supply, technology improvements, renewable energy solutions, and conservation measures. It was suggested that in order to implement cleaner and greener energy technology, it is important to understand the nature of global energy systems. The challenge of defining the related ideologies of green energy and sustainability was discussed. In this paper, green energy was defined as indicating environmental compatibility with little or no negative environmental impact. This differs from the concept of sustainability, which was defined as an action that can be repeated continuously without depleting or diminishing resources. In general, green energy options include most technologies that do not involve fossil fuels. However, this paper considered a spectrum of shades of green with some options being low-impact and cleaner, and others having high environmental impacts. As an example, the authors presented the ongoing debate over nuclear energy and hydro power. Although both energy sources can be sustainable over hundreds of years, they may or may not be environmentally compatible because they are often considered to have problematic attributes. Energy from renewable sources currently accounts for less than 20 per cent of world primary energy supply because price and implementation challenges in the renewables sector do not generally compare well to other energy sources. With high energy-demands beginning to strain finite fossil-energy supplies, the energy sector is now subject to more frequent disruptions and price fluctuations. Future growth from emerging economies will demand more energy and resources. This paper also emphasized that the proportion of green sources of energy has not increased substantially in the past 3 decades, and despite many technological advances, there continue to be significant

Simulation of embedded systems for energy consumption estimation

Energy Technology Data Exchange (ETDEWEB)

Lafond, S.

2009-07-01

Technology developments in semiconductor fabrication along with a rapid expansion of the market for portable devices, such as PDAs and mobile phones, make the energy consumption of embedded systems a major problem. Indeed the need to provide an increasing number of computational intensive applications and at the same time to maximize the battery life of portable devices can be seen as incompatible trends. System simulation is a flexible and convenient method for analyzinging and exploring the performance of a system or sub-system. At the same time, the increasing use of computational intensive applications strengthens the need to maximize the battery life of portable devices. As a consequence, the simulation of embedded systems for energy consumption estimation is becoming essential in order to study and explore the influence of system design choices on the system energy consumption. The original publications presented in the second part of this thesis propose several frameworks for evaluating the effects of particular system and software architectures on the system energy consumption. From a software point of view Java and C based applications are studied, and from a hardware perspective systems using general purpose processor and heterogeneous platforms with dedicated hardware accelerators are analyzed. Papers 1 and 2 present a framework for estimating the energy consumption of an embedded Java Virtual Machine and show how an accurate energy consumption model of Java opcodes can be obtained. Paper 3 evaluates the cost-effectiveness of Forward Error Correction algorithms in terms of energy consumption and demonstrates that a substantial energy saving is achievable in a DVB-H receiver when a FEC algorithm is used for file downloading scenarios. Paper 4 and 5 present the simulation of heterogeneous platforms and point out the drawback of different mechanisms used to synchronize a hardware accelerator used as a peripheral device. Paper 6 shows that the use of a multi

General properties of quantum optical systems in a strong field limit

Science.gov (United States)

Chumakov, S. M.; Klimov, Andrei B.

1994-01-01

We investigate the dynamics of an arbitrary atomic system (n-level atoms or many n-level atoms) interacting with a resonant quantized mode of an em field. If the initial field state is a coherent state with a large photon number then the system dynamics possesses some general features, independently of the particular structure of the atomic system. Namely, trapping states, factorization of the wave function, collapses and revivals of the atomic energy oscillations are discussed.

Bulk energy storage increases United States electricity system emissions.

Science.gov (United States)

Hittinger, Eric S; Azevedo, Inês M L

2015-03-03

Bulk energy storage is generally considered an important contributor for the transition toward a more flexible and sustainable electricity system. Although economically valuable, storage is not fundamentally a "green" technology, leading to reductions in emissions. We model the economic and emissions effects of bulk energy storage providing an energy arbitrage service. We calculate the profits under two scenarios (perfect and imperfect information about future electricity prices), and estimate the effect of bulk storage on net emissions of CO2, SO2, and NOx for 20 eGRID subregions in the United States. We find that net system CO2 emissions resulting from storage operation are nontrivial when compared to the emissions from electricity generation, ranging from 104 to 407 kg/MWh of delivered energy depending on location, storage operation mode, and assumptions regarding carbon intensity. Net NOx emissions range from -0.16 (i.e., producing net savings) to 0.49 kg/MWh, and are generally small when compared to average generation-related emissions. Net SO2 emissions from storage operation range from -0.01 to 1.7 kg/MWh, depending on location and storage operation mode.

Advanced energy conversion and application - Decentralized energy systems. Papers; Fortschrittliche Energiewandlung und -anwendung - Schwerpunkt: Dezentrale Energiesysteme. Vortraege

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-07-01

Decentralized energy systems is the major topic of this VDI report which contains the proceedings of the VDI conference on advanced energy conversion and application. The decentralized energy systems are in the focus because it is expected that they will gain in significance in the course of restructuring and liberalisation of the energy markets and growing commitment to greenhouse gas mitigation. The subjects of the papers are the cogeneration technology in general, and specific systems for combined generation of heat, power and cold,(CHPC systems), systems for renewable energy generation, industrial energy technology, and analysis and optimization of energy systems. The report is intended to serve as a source of guidance and reference for manufacturers and operators of decentralized energy systems, for decision-making on energy policy, and for the energy industry, counselling firms and regulatory/surveillance bodies, and members of universities involved in relevant research and development work. (orig./CB) [German] Themenschwerpunkt des VDI-Berichts sind die dezentralen Energiesysteme, die im Spannungsfeld von fortschreitender Liberalisierung der Energiemaerkte und der Bemuehungen um die Reduzierung von Emissionen an Bedeutung gewinnen. Dabei widmen sich die Beitraege den Systemen zur Kraft-Waerme-Kaelte-Kopplung und zur Nutzung erneuerbarer Energie sowie der industriellen Energietechnik und der Analyse und Optimierung von Energiesystemen. Der Bericht wendet sich an Hersteller und Betreiber dezentraler Energieanlagen, an Entscheidungstraeger aus Politik und Wirtschaft, an Berater und Ueberwachungsinstitutionen sowie an auf diesem Gebiet taetige Hochschullehrer und -mitarbeiter. (orig.)

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.

Energy Savings Forecast of Solid-State Lighting in General Illumination Applications

Energy Technology Data Exchange (ETDEWEB)

none,

2014-08-29

With declining production costs and increasing technical capabilities, LED adoption has recently gained momentum in general illumination applications. This is a positive development for our energy infrastructure, as LEDs use significantly less electricity per lumen produced than many traditional lighting technologies. The U.S. Department of Energy’s Energy Savings Forecast of Solid-State Lighting in General Illumination Applications examines the expected market penetration and resulting energy savings of light-emitting diode, or LED, lamps and luminaires from today through 2030.

Energy Systems Integration News | Energy Systems Integration Facility |

Science.gov (United States)

grids. In terms of paper sessions, NREL ESI researcher Santosh Veda chaired a session on energy Kroposki chaired a session on advanced renewable energy power systems. While Veda, Muljadi, and Kroposki

Effective medium super-cell approximation for interacting disordered systems: an alternative real-space derivation of generalized dynamical cluster approximation

International Nuclear Information System (INIS)

Moradian, Rostam

2006-01-01

We develop a generalized real-space effective medium super-cell approximation (EMSCA) method to treat the electronic states of interacting disordered systems. This method is general and allows randomness both in the on-site energies and in the hopping integrals. For a non-interacting disordered system, in the special case of randomness in the on-site energies, this method is equivalent to the non-local coherent potential approximation (NLCPA) derived previously. Also, for an interacting system the EMSCA method leads to the real-space derivation of the generalized dynamical cluster approximation (DCA) for a general lattice structure. We found that the original DCA and the NLCPA are two simple cases of this technique, so the EMSCA is equivalent to the generalized DCA where there is included interaction and randomness in the on-site energies and in the hopping integrals. All of the equations of this formalism are derived by using the effective medium theory in real space

Proposed general amendments to the atomic energy control regulations

International Nuclear Information System (INIS)

1986-01-01

Canada's Atomic Energy Control Act defines the powers and responsibilities of the Atomic Energy Control Board (AECB). Among these is to make regulations to control the development, application and use of atomic energy. In these proposed general amendments to the Atomic Energy Control Regulations substantial changes are proposed in the designation of the authority of AECB staff, exemptions from licensing, international safeguards, duties of licensees and atomic radiation workers, security of information, and provision for hearings. The scope of the control of atomic energy has been redefined as relating to matters of health, safety, security, international safeguards, and the protection of the environment

Dissipation, generalized free energy, and a self-consistent nonequilibrium thermodynamics of chemically driven open subsystems.

Science.gov (United States)

Ge, Hao; Qian, Hong

2013-06-01

Nonequilibrium thermodynamics of a system situated in a sustained environment with influx and efflux is usually treated as a subsystem in a larger, closed "universe." A question remains with regard to what the minimally required description for the surrounding of such an open driven system is so that its nonequilibrium thermodynamics can be established solely based on the internal stochastic kinetics. We provide a solution to this problem using insights from studies of molecular motors in a chemical nonequilibrium steady state (NESS) with sustained external drive through a regenerating system or in a quasisteady state (QSS) with an excess amount of adenosine triphosphate (ATP), adenosine diphosphate (ADP), and inorganic phosphate (Pi). We introduce the key notion of minimal work that is needed, W(min), for the external regenerating system to sustain a NESS (e.g., maintaining constant concentrations of ATP, ADP and Pi for a molecular motor). Using a Markov (master-equation) description of a motor protein, we illustrate that the NESS and QSS have identical kinetics as well as the second law in terms of the same positive entropy production rate. The heat dissipation of a NESS without mechanical output is exactly the W(min). This provides a justification for introducing an ideal external regenerating system and yields a free-energy balance equation between the net free-energy input F(in) and total dissipation F(dis) in an NESS: F(in) consists of chemical input minus mechanical output; F(dis) consists of dissipative heat, i.e. the amount of useful energy becoming heat, which also equals the NESS entropy production. Furthermore, we show that for nonstationary systems, the F(dis) and F(in) correspond to the entropy production rate and housekeeping heat in stochastic thermodynamics and identify a relative entropy H as a generalized free energy. We reach a new formulation of Markovian nonequilibrium thermodynamics based on only the internal kinetic equation without further

A GENERALIZED COEFFICIENT OF FRICTION FOR ASSESSING ENERGY EFFICIENCY OF BEARING SYSTEMS

OpenAIRE

Al-Bender, Farid

2011-01-01

Environmental impact estimations, often carried out in the framework of Life Cycle Assessment (LCA) on production machines and machine tools, show that a significant (if not the greatest) part of the environmental impact is related to the use-phase of the machine. A closer analysis reveals that the energy efficiency of the bearing systems, i.e. their friction loss, is the main culprit in this. Cost reduction and maintenance savings were the main motivations that initiated tribology as a s...

Generalized entropy formalism and a new holographic dark energy model

Science.gov (United States)

Sayahian Jahromi, A.; Moosavi, S. A.; Moradpour, H.; Morais Graça, J. P.; Lobo, I. P.; Salako, I. G.; Jawad, A.

2018-05-01

Recently, the Rényi and Tsallis generalized entropies have extensively been used in order to study various cosmological and gravitational setups. Here, using a special type of generalized entropy, a generalization of both the Rényi and Tsallis entropy, together with holographic principle, we build a new model for holographic dark energy. Thereinafter, considering a flat FRW universe, filled by a pressureless component and the new obtained dark energy model, the evolution of cosmos has been investigated showing satisfactory results and behavior. In our model, the Hubble horizon plays the role of IR cutoff, and there is no mutual interaction between the cosmos components. Our results indicate that the generalized entropy formalism may open a new window to become more familiar with the nature of spacetime and its properties.

Model for Calculating Electrolytic Shunt Path Losses in Large Electrochemical Energy Conversion Systems

Science.gov (United States)

Prokopius, P. R.

1976-01-01

Generalized analysis and solution techniques were developed to evaluate the shunt power losses in electrochemical systems designed with a common or circulating electrolyte supply. Sample data are presented for a hypothetical bulk energy storage redox system, and the general applicability of the analysis technique is discussed.

The Impact of Energy Price Decline on China's Energy-Economy-Environment System Variables Using a CGE Model

DEFF Research Database (Denmark)

Guo, Zhengquan; Wang, Daojuan; Chen, Chong

In recent years, prices of coal and crude oil have fallen significantly. These declines have had a large impact on China’s energy-economy-environment system variables. This paper establishes a computable general equilibrium model to systematically analyse the impact of coal price changes alone...... or the decline of both coal and oil prices on the variables of China's energy-economy-environment system. The results of the analysis show that the decline of the coal price alone or of coal and crude oil prices together will lead to a significant increase in demand for either coal and total energy or coal...

Indicators System Creation For The Energy Efficiency Benchmarking Of Municipal Power System Facilities

Directory of Open Access Journals (Sweden)

Davydenko L.V.

2015-04-01

Full Text Available The issues of the dataware of the comparative analysis procedure (benchmarking for municipal power system facilities energy efficiency level estimation with a view of the hierarchical structure of the heat supply system are considered. The aim of the paper is the system of indicators formation for characterizing the efficiency of energy usage as on objects on lowest so on highest levels of power systems, proceeding from features of their functioning. Benchmarking methodology allows carrying out the estimation of energy efficiency level on the base of a plurality of parameters without their generalization in one indicator, but requires ensuring their comparability. Using the methodology of available statistical information that did not require deep specification and additional inspection structuring objectives and tasks of energy efficiency estimation problem has been proposed for ensuring the opportunity of benchmarking procedure implementation. This makes it possible to form the subset of indicators that ensure enough specification of the object of study, taking into account the degree of abstraction for every hierarchical level or sub problem. For a comparative analysis of energy using efficiency in municipal power systems at the highest levels of the hierarchy a plurality of indicators of the energy efficiency has been formed. Indicators have been determined with consideration of the structural elements of heat supply systems, but allowing taking into account the efficiency of the initial state of the objects, their functioning, and the questions of energy resources accounting organization. Usage of the proposed indicators provides implementation of energy using efficiency monitoring in the municipal power system and allows getting complete overview of the problem.

Emerging nuclear energy systems and nuclear weapon proliferation

International Nuclear Information System (INIS)

Gsponer, A.; Sahin, S.; Jasani, B.

1983-01-01

Generally when considering problems of proliferation of nuclear weapons, discussions are focused on horizontal proliferation. However, the emerging nuclear energy systems currently have an impact mainly on vertical proliferation. The paper indicates that technologies connected with emerging nuclear energy systems, such as fusion reactors and accelerators, enhance the knowledge of thermonuclear weapon physics and will enable production of military useful nuclear materials (including some rare elements). At present such technologies are enhancing the arsenal of the nuclear weapon states. But one should not forget the future implications for horizontal proliferation of nuclear weapons as some of the techniques will in the near future be within the technological and economic capabilities of non-nuclear weapon states. Some of these systems are not under any international control. (orig.) [de

Future UK markets for stand-alone renewable energy systems

International Nuclear Information System (INIS)

Paish, O.

1999-01-01

A study to identify and quantify the market for stand-alone renewable energy supplies of power (photovoltaics, wind and micro-hydro electricity systems) was described. The study focused on small systems, generally less than a few kW installed capacity. It was suggested that in the UK, the emphasis on grid-connected renewable energy technologies (RETs) has blurred the fact that it is 'off-grid' renewable systems that can offer more immediate real commercial markets for the renewables business. With the likelihood of a significant increase in demand for renewables world wide over the next ten years, the UK needs to make a special effort to become involved

Bio energy: Bio energy in the Energy System of the Future

International Nuclear Information System (INIS)

Finden, Per; Soerensen, Heidi; Wilhelmsen, Gunnar

2001-01-01

This is Chapter 7, the final chapter, of the book ''Bio energy - Environment, technique and market''. Its main sections are: (1) Factors leading to changes in the energy systems, (2) The energy systems of the future, globally, (3) The future energy system in Norway and (4) Norwegian energy policy at the crossroads

Effects of energy drinks on the cardiovascular system.

Science.gov (United States)

Wassef, Bishoy; Kohansieh, Michelle; Makaryus, Amgad N

2017-11-26

Throughout the last decade, the use of energy drinks has been increasingly looked upon with caution as potentially dangerous due to their perceived strong concentration of caffeine aside from other substances such as taurine, guarana, and L-carnitine that are largely unknown to the general public. In addition, a large number of energy drink intoxications have been reported all over the world including cases of seizures and arrhythmias. In this paper, we focus on the effect of energy drinks on the cardiovascular system and whether the current ongoing call for the products' sales and regulation of their contents should continue.

Approach to the holistic analysis of the system man--energy--environment

Energy Technology Data Exchange (ETDEWEB)

Voss, A

1973-07-01

Thesis. Energy is generally considered as the main access to the modern industrial society. The availability of sufficient amounts of energy as due to fundamental importance for the development of society. Besides the demand on economical energy maintenance, there are intensively occurring ecological and supply-technical aspects. whose importance advances permanently with the exponential increase of the energy consumption. A holistic analysis for the system man--enengy -environment regarding economical, ecological, and technical aspects is presented. The aim is to comprehend all significant influence factors and interactions as well as to compare and to evaluate the positive and negative effects of an increasing enengy consumption and its protection by alternative energy supply systems. For such complex systems new methods developed in the field of system engineering, especially cybernetic simulation, have to be used for the derivation of adequate aid for decision. (auth)

General framework and key technologies of national nuclear emergency system

International Nuclear Information System (INIS)

Yuan Feng; Li Xudong; Zhu Guangying; Song Yafeng; Zeng Suotian; Shen Lifeng

2014-01-01

Nuclear emergency is the important safeguard for the sustainable development of nuclear energy, and is the significant part of national public crisis management. The paper gives the definition of nuclear emergency system explicitly based on the analysis of the characteristics of the nuclear emergency, and through the research of the structure and general framework, the general framework of the national nuclear emergency management system (NNEMS) is obtained, which is constructed in four parts, including one integrative platform, six layers, eight applications and two systems, then the paper indicate that the architecture of national emergency system that should be laid out by three-tiers, i.e. national, provincial and organizations with nuclear facilities, and also describe the functions of the NNEMS on the nuclear emergency's workflow. Finally, the paper discuss the key technology that NNIEMS needed, such as WebGIS, auxiliary decision-making, digitalized preplan and the conformity and usage of resources, and analyze the technical principle in details. (authors)

Croatian Energy System Defossilization

International Nuclear Information System (INIS)

Potocnik, V.

2013-01-01

Defossilization of an energy system, as primary cause of the actual climate change, means exchange of predominantly imported fossil fuels with climate more convenient energy carriers, facilitating thus the way out of crisis.Overview of the world and Croatian energy system situation is presented as well as the overview of climate change. The most important Croatian energy system defossilization measures-energy efficiency increase, renewable energy inclusion and others - are described.(author)

Revisit ocean thermal energy conversion system

International Nuclear Information System (INIS)

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

2003-01-01

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

76 FR 11437 - Application To Export Electric Energy; Societe Generale Energy Corp.

Science.gov (United States)

2011-03-02

... reliability of the U.S. electric power supply system. Copies of this application will be made available, upon... surplus energy purchased from electric utilities, Federal power marketing agencies and other entities... DEPARTMENT OF ENERGY [OE Docket No. EA-376] Application To Export Electric Energy; Societe...

INPRO Methodology to evaluate the Mexico nuclear energy system

International Nuclear Information System (INIS)

Cruz S, R. R.; Martin del C, C.

2016-09-01

The International Atomic Energy Agency has developed the so-called International Project on Fuel Cycles and Innovative Nuclear Reactors (INPRO), in order to make nuclear energy available to meet the energy needs of the 21 century, in a sustainable way. One of the tasks of the project is the evaluation of the nuclear systems, to check whether they meet the objectives of the project and whether they are sustainable. This paper explains the rationale and general characteristics of the project in the evaluation of nuclear energy systems based on the concept of sustainable development. It describes the methodology developed to carry out this evaluation, divided into seven areas, such as economic, environmental, security, etc., which together make up the sustainable development of energy through nuclear systems. The economic area is analyzed and the evaluation criteria and parameters established by INPRO are discussed, in order to evaluate the Mexican nuclear energy system using Nest (software developed within the same project) as a tool to support the economic evaluation of nuclear systems. Based on the energy strategy proposed by the Energy Secretary of the Mexican Government which seeks to reduce the greenhouse gas emissions from the national electricity generation park, two types of reactor of currently available technology (A BWR and AP1000), were compared and these in turn with other alternative energy generation technologies, such as combined cycle, geothermal and wind plants. Also, the results of the application of the INPRO methodology are presented. Finally, the recommendations on actions that could lead the Mexican nuclear energy system towards sustainable development and conclusions on the application of the methodology to the Mexican case are mentioned. (Author)

Solar energy conversion systems

CERN Document Server

Brownson, Jeffrey R S

2013-01-01

Solar energy conversion requires a different mind-set from traditional energy engineering in order to assess distribution, scales of use, systems design, predictive economic models for fluctuating solar resources, and planning to address transient cycles and social adoption. Solar Energy Conversion Systems examines solar energy conversion as an integrative design process, applying systems thinking methods to a solid knowledge base for creators of solar energy systems. This approach permits different levels of access for the emerging broad audience of scientists, engineers, architects, planners

Smart energy and smart energy systems

DEFF Research Database (Denmark)

Lund, Henrik; Østergaard, Poul Alberg; Connolly, David

2017-01-01

In recent years, the terms “Smart Energy” and “Smart Energy Systems” have been used to express an approach that reaches broader than the term “Smart grid”. Where Smart Grids focus primarily on the electricity sector, Smart Energy Systems take an integrated holistic focus on the inclusion of more...... sectors (electricity, heating, cooling, industry, buildings and transportation) and allows for the identification of more achievable and affordable solutions to the transformation into future renewable and sustainable energy solutions. This paper first makes a review of the scientific literature within...... the field. Thereafter it discusses the term Smart Energy Systems with regard to the issues of definition, identification of solu- tions, modelling, and integration of storage. The conclusion is that the Smart Energy System concept represents a scientific shift in paradigms away from single-sector thinking...

Simulation model for wind energy storage systems. Volume III. Program descriptions. [SIMWEST CODE

Energy Technology Data Exchange (ETDEWEB)

Warren, A.W.; Edsinger, R.W.; Burroughs, J.D.

1977-08-01

The effort developed a comprehensive computer program for the modeling of wind energy/storage systems utilizing any combination of five types of storage (pumped hydro, battery, thermal, flywheel and pneumatic). An acronym for the program is SIMWEST (Simulation Model for Wind Energy Storage). The level of detail of SIMWEST is consistent with a role of evaluating the economic feasibility as well as the general performance of wind energy systems. The software package consists of two basic programs and a library of system, environmental, and load components. Volume III, the SIMWEST program description contains program descriptions, flow charts and program listings for the SIMWEST Model Generation Program, the Simulation program, the File Maintenance program and the Printer Plotter program. Volume III generally would not be required by SIMWEST user.

Geothermal pump down-hole energy regeneration system

Science.gov (United States)

Matthews, Hugh B.

1982-01-01

Geothermal deep well energy extraction apparatus is provided of the general kind in which solute-bearing hot water is pumped to the earth's surface from a subterranean location by utilizing thermal energy extracted from the hot water for operating a turbine motor for driving an electrical power generator at the earth 3 s surface, the solute bearing water being returned into the earth by a reinjection well. Efficiency of operation of the total system is increased by an arrangement of coaxial conduits for greatly reducing the flow of heat from the rising brine into the rising exhaust of the down-well turbine motor.

Generalized Asynchronous Systems

Directory of Open Access Journals (Sweden)

E. S. Kudryashova

2012-01-01

Full Text Available The paper consider a mathematical model of a concurrent system, the special case of which is an asynchronous system. Distributed asynchronous automata are introduced here. It is proved that Petri nets and transition systems with independence can be considered as distributed asynchronous automata. Time distributed asynchronous automata are defined in a standard way by correspondence which relates events with time intervals. It is proved that the time distributed asynchronous automata generalize time Petri nets and asynchronous systems.

Energy taxes and wages in a general equilibrium model of production

International Nuclear Information System (INIS)

Thompson, H.

2000-01-01

Energy taxes are responsible for a good deal of observed differences in energy prices across states and countries. They alter patterns of production and income distribution. The present paper examines the potential of energy taxes to lower wages in a general equilibrium model of production with capital, labour and energy inputs. (Author)

Manifestations of dark energy in the solar system

Czech Academy of Sciences Publication Activity Database

Křížek, Michal; Somer, L.

2015-01-01

Roč. 21, č. 1 (2015), s. 59-72 ISSN 0202-2893 R&D Projects: GA ČR GA14-02067S Institutional support: RVO:67985840 Keywords : dark energy * solar system Subject RIV: BA - General Mathematics Impact factor: 0.909, year: 2015 http://link.springer.com/article/10.1134%2FS0202289315010090

Flexible energy systems

DEFF Research Database (Denmark)

Lund, Henrik

2003-01-01

The paper discusses and analyses diffent national strategies and points out key changes in the energy system in order to achieve a system which can benefit from a high percentage of wind and CHP without having surplus production problems, introduced here as a flexible energy system....

Facilitating energy transition through energy commons : An application of socio-ecological systems framework for integrated community energy systems

NARCIS (Netherlands)

Acosta, Cristina; Ortega, Mariana; Bunsen, Till; Koirala, B.P.; Ghorbani, A.

2018-01-01

Integrated Community Energy Systems (ICES) are an emerging local energy system focusing on the collective use of distributed energy resources (DER). These socio-technical systems (STSs) have a high potential to advance the transition towards socially inclusive, environmentally-friendly energy

Facilitating energy transition through energy commons : An application of socio-ecological systems framework for integrated community energy systems

NARCIS (Netherlands)

Acosta, Cristina; Ortega, Mariana; Bunsen, Till; Koirala, Binod Prasad; Ghorbani, Amineh

2018-01-01

Integrated Community Energy Systems (ICES) are an emerging local energy system focusing on the collective use of distributed energy resources (DER). These socio-technical systems (STSs) have a high potential to advance the transition towards socially inclusive, environmentally-friendly energy

Polish energy-system modernisation

International Nuclear Information System (INIS)

Drozdz, M.

2003-01-01

The Polish energy-system needs intensive investments in new technologies, which are energy efficient, clean and cost effective. Since the early 1990s, the Polish economy has had practically full access to modern technological devices, equipment and technologies. Introducing new technologies is a difficult task for project teams, constructors and investors. The author presents a set of principles for project teams useful in planning and energy modernisation. Several essential features are discussed: Energy-efficient appliances and systems; Choice of energy carriers, media and fuels; Optimal tariffs, maximum power and installed power; Intelligent, integrated, steering systems; Waste-energy recovery; Renewable-energy recovery. In practice there are several difficulties connected with planning and realising good technological and economic solutions. The author presents his own experiences of energy-system modernisation of industrial processes and building new objects. (Author)

New secondary energy systems

International Nuclear Information System (INIS)

Schulten, R.

1977-01-01

As an introduction, the FRG's energy industry situation is described, secondary energy systems to be taken into consideration are classified, and appropriate market requirements are analyzed. Dealt with is district heating, i.e. the direct transport of heat by means of circulating media, and long-distance energy, i.e. the long-distance energy transport by means of chemical conversion in closed- or open-cycle systems. In closed-cycle systems heat is transported in the form of chemical latent energy. In contrast to this, chemical energy is transported in open-cycle systems in the form of fuel gases produced by coal gasification or by thermochemical water splitting. (GG) [de

Solar energy system performance evaluation: Seasonal report for IBM system 1A, Huntsville, Alabama

Science.gov (United States)

1980-01-01

The operational and thermal performance of the solar energy system, Sims Prototype System 1A, is described. The system was designed by IBM to provide 50 to 60 percent of the space heating and domestic hot water preheating load to a 2,000 square foot floor space single family residence in the Huntsville area. The load design temperature inside the building was to be maintained at 70 degrees fahrenheit with auxiliary energy for heating supplied by an electric heat pump assisted by an electric resistance strip heater. In general the disappointing operation of this system is attributed to the manner in which it was used. The system was designed for residential application and used to satisfy the demands of an office environment. The differences were: (1) inside temperature was not maintained at 70 F as expected; and (2) hot water usage was much lower than expected. The conclusion is that the solar energy system must be designed for the type of application in which it is used. Misapplication usually will have an adverse affect on system performance.

Status of the new nuclear energy systems study in CIAE

International Nuclear Information System (INIS)

Ding, D.; Luo, Z.; Xu, M.

2003-01-01

The nuclear energy civil-application has been started in China. To meet the long-term sustainable primary energy supply it could be envisaged that the nuclear power systems will be developed in large scale. Following three key points must be satisfied by the future nuclear energy systems: - more safer nuclear energy systems than recent those should be developed to decrease the risk of core-melten and unforeseen release of radioactive materials; - long lived minor actinides and long lived fission products must be safely treated to assure a proper environment; - uranium resource should be sufficiently utilized. In order to meet above general requirements, the fast reactor technology development has been launched and the basic researches of Accelerator Driven Subcritical facility (ADS) system has been started in China. The activity of the construction of the China Experimental Fast Reactor and plan for next step, some calculation results on core physics study of ADS, some results on target physics and a proposed verification facility are briefed in the paper. (author)

Solar energy system performance evaluaton: Seasonal report for Solaron-Akron, Akron, Ohio

Science.gov (United States)

1980-05-01

The operational and thermal performance of the solar energy system by Solaron Corporation is described. The system was designed to provide an 1940 square foot floor area with space heating and domestic hot water for a dual-level single family residence in Akron, Ohio. The solar energy system uses air as the heat transport medium, has a 546 square foot flat plate collector array subsystem, a 270 cubic foot rock thermal storage bin subsystem, a domestic hot water preheat tank, pumps, controls and transport lines. In general, the performance of the Solaron Akron solar energy system was somewhat difficult to assess for the November 1978 through October 1979 time period. The problems relating to the control systems, various solar energy leakages, air flow correction factors and instrumentation cause a significant amount of subjectivity to be involved in the performance assessment for this solar energy system. Had these problems not been present, it is felt that this system would have exhibited a resonably high level of measured performance.

The Generalized Conversion Factor in Einstein's Mass-Energy Equation

Directory of Open Access Journals (Sweden)

Ajay Sharma

2008-07-01

Full Text Available Einstein's September 1905 paper is origin of light energy-mass inter conversion equation ($L = Delta mc^{2}$ and Einstein speculated $E = Delta mc^{2}$ from it by simply replacing $L$ by $E$. From its critical analysis it follows that $L = Delta mc^{2}$ is only true under special or ideal conditions. Under general cases the result is $L propto Delta mc^{2}$ ($E propto Delta mc^{2}$. Consequently an alternate equation $Delta E = A ub c^{2}Delta M$ has been suggested, which implies that energy emitted on annihilation of mass can be equal, less and more than predicted by $Delta E = Delta mc^{2}$. The total kinetic energy of fission fragments of U-235 or Pu-239 is found experimentally 20-60 MeV less than Q-value predicted by $Delta mc^{2}$. The mass of particle Ds (2317 discovered at SLAC, is more than current estimates. In many reactions including chemical reactions $E = Delta mc^{2}$ is not confirmed yet, but regarded as true. It implies the conversion factor than $c^{2}$ is possible. These phenomena can be explained with help of generalized mass-energy equation $Delta E = A ub c^{2}Delta M$.

An energy systems engineering approach to the optimal design of energy systems in commercial buildings

Energy Technology Data Exchange (ETDEWEB)

Liu, Pei; Pistikopoulos, Efstratios N. [Centre for Process Systems Engineering (CPSE), Department of Chemical Engineering, Imperial College London, London SW7 2AZ (United Kingdom); Li, Zheng [Department of Thermal Engineering, Tsinghua University, Beijing 100084 (China)

2010-08-15

Energy consumption in commercial buildings accounts for a significant proportion of worldwide energy consumption. Any increase in the energy efficiency of the energy systems for commercial buildings would lead to significant energy savings and emissions reductions. In this work, we introduce an energy systems engineering framework towards the optimal design of such energy systems with improved energy efficiency and environmental performance. The framework features a superstructure representation of the various energy technology alternatives, a mixed-integer optimization formulation of the energy systems design problem, and a multi-objective design optimization solution strategy, where economic and environmental criteria are simultaneously considered and properly traded off. A case study of a supermarket energy systems design is presented to illustrate the key steps and potential of the proposed energy systems engineering approach. (author)

An energy systems engineering approach to the optimal design of energy systems in commercial buildings

International Nuclear Information System (INIS)

Liu Pei; Pistikopoulos, Efstratios N.; Li Zheng

2010-01-01

Energy consumption in commercial buildings accounts for a significant proportion of worldwide energy consumption. Any increase in the energy efficiency of the energy systems for commercial buildings would lead to significant energy savings and emissions reductions. In this work, we introduce an energy systems engineering framework towards the optimal design of such energy systems with improved energy efficiency and environmental performance. The framework features a superstructure representation of the various energy technology alternatives, a mixed-integer optimization formulation of the energy systems design problem, and a multi-objective design optimization solution strategy, where economic and environmental criteria are simultaneously considered and properly traded off. A case study of a supermarket energy systems design is presented to illustrate the key steps and potential of the proposed energy systems engineering approach.

An energy systems engineering approach to the optimal design of energy systems in commercial buildings

Energy Technology Data Exchange (ETDEWEB)

Liu Pei [Centre for Process Systems Engineering (CPSE), Department of Chemical Engineering, Imperial College London, London SW7 2AZ (United Kingdom); Pistikopoulos, Efstratios N., E-mail: e.pistikopoulos@imperial.ac.u [Centre for Process Systems Engineering (CPSE), Department of Chemical Engineering, Imperial College London, London SW7 2AZ (United Kingdom); Li Zheng [Department of Thermal Engineering, Tsinghua University, Beijing 100084 (China)

2010-08-15

Energy consumption in commercial buildings accounts for a significant proportion of worldwide energy consumption. Any increase in the energy efficiency of the energy systems for commercial buildings would lead to significant energy savings and emissions reductions. In this work, we introduce an energy systems engineering framework towards the optimal design of such energy systems with improved energy efficiency and environmental performance. The framework features a superstructure representation of the various energy technology alternatives, a mixed-integer optimization formulation of the energy systems design problem, and a multi-objective design optimization solution strategy, where economic and environmental criteria are simultaneously considered and properly traded off. A case study of a supermarket energy systems design is presented to illustrate the key steps and potential of the proposed energy systems engineering approach.

Centralization and decentralization in energy systems and associated risks

International Nuclear Information System (INIS)

Rehm, W.; Schinner, F.; Kromp, W.

1998-01-01

Full text of publication follows: the concept of centralization/decentralization is - considering its widespread use - surprisingly ill-defined. Within the SERF-program (Socio Economic Research on Fusion) an attempt is made to clarify the complex issue of centralization/decentralization and to analyze its expected interaction with electricity production system in the case of nuclear fusion. Fusion research at the time is a multinational, highly centralized undertaking. As a result of this, and due to the expected large energy production units, it is generally expected that fusion will be embedded in a highly centralized, international energy supply system. The degree of centralization of an energy supply system, however, is believed to have for reaching consequences on the stability of the system, and beyond that, on decision making processes in energy policy, as well as democratic structures on the national or even international level. Internationalization might require control instruments that do not exist so far. Amongst other reservations, it is the possibly unwanted consequences of such a highly centralized, international energy supply system that limit acceptance of the fusion technology in the public. Therefore, centralization and decentralization trends of energy supply systems over the years are being looked at, to study their influence on the political and social systems (and vice-versa). In a first step, an attempt is made to classify centralization. Careful analyses and evaluation of available literature revealed a broad spectrum of different forms and degrees of centralization. Various parameters describing energy production and distribution are used. A differentiation of centralization on a technical and on an organizational level seems necessary, although they are not fully independent of each other. Beyond this, the choice of parameters must depend on the questions to be addressed. A new approach defining different levels and degrees of

Centralization and decentralization in energy systems and associated risks

Energy Technology Data Exchange (ETDEWEB)

Rehm, W.; Schinner, F.; Kromp, W. [Vienna Univ., Institute of Risk Research, IRR (Austria)

1998-07-01

Full text of publication follows: the concept of centralization/decentralization is - considering its widespread use - surprisingly ill-defined. Within the SERF-program (Socio Economic Research on Fusion) an attempt is made to clarify the complex issue of centralization/decentralization and to analyze its expected interaction with electricity production system in the case of nuclear fusion. Fusion research at the time is a multinational, highly centralized undertaking. As a result of this, and due to the expected large energy production units, it is generally expected that fusion will be embedded in a highly centralized, international energy supply system. The degree of centralization of an energy supply system, however, is believed to have for reaching consequences on the stability of the system, and beyond that, on decision making processes in energy policy, as well as democratic structures on the national or even international level. Internationalization might require control instruments that do not exist so far. Amongst other reservations, it is the possibly unwanted consequences of such a highly centralized, international energy supply system that limit acceptance of the fusion technology in the public. Therefore, centralization and decentralization trends of energy supply systems over the years are being looked at, to study their influence on the political and social systems (and vice-versa). In a first step, an attempt is made to classify centralization. Careful analyses and evaluation of available literature revealed a broad spectrum of different forms and degrees of centralization. Various parameters describing energy production and distribution are used. A differentiation of centralization on a technical and on an organizational level seems necessary, although they are not fully independent of each other. Beyond this, the choice of parameters must depend on the questions to be addressed. A new approach defining different levels and degrees of

The network-based energy management system for convenience stores

Energy Technology Data Exchange (ETDEWEB)

Wang, An-Ping; Hsu, Pau-Lo [Department of Electrical and Control Engineering, National Chiao-Tung University, 1001 Ta-Hsiue Road, Hsinchu City 310 (China)

2008-07-01

Convenience stores generally consume energy higher than other retailing merchants. As the problem of energy shortage becomes more serious during summer, almost all convenience stores sign a contract with power plants, which provides for fines if demand limiting occurs in Taiwan and many other countries. Therefore, a reliable and effective method to reduce their utility consumption is required for modern business and industry. This research integrates the remote sensors, the control network, and the embedded system technologies to construct a distributed energy management control system for dedicated convenience stores. Energy consumption can thus be reasonably managed with demand limits by measuring and analyzing the power consumption sources in four major subsystems of convenience stores, namely, (1) air-conditioning, (2) lighting, (3) heating, and (4) refrigeration. By applying the proposed demand prediction and control method, the demand limiting condition can be properly predicted, and the possible peak load can thus be eliminated via the network control mechanism. Moreover, by integrating the LonWork fieldbus and the WinCE operating system (OS), the proposed system has been successfully applied to a convenience store. The experimental results indicate that the proposed distributed energy management system suitably predicts the peak loading condition and successfully prevents its occurrence by switching the air-conditioning system without affecting the indoor temperature regulation. (author)

Hybrid Energy System Design of Micro Hydro-PV-biogas Based Micro-grid

Science.gov (United States)

Nishrina; Abdullah, A. G.; Risdiyanto, A.; Nandiyanto, ABD

2017-03-01

Hybrid renewable energy system is an arrangement of one or more sources of renewable energy and also conventional energy. This paper describes a simulation results of hybrid renewable power system based on the available potential in an educational institution in Indonesia. HOMER software was used to simulate and analyse both in terms of optimization and economic terms. This software was developed through 3 main principles; simulation, optimization, and sensitivity analysis. Generally, the presented results show that the software can demonstrate a feasible hybrid power system as well to be realized. The entire demand in case study area can be supplied by the system configuration and can be met by ¾ of electricity production. So, there are ¼ of generated energy became an excess electricity.

Heat-pump-centered integrated community energy systems. System development, Consolidated Natural Gas Service Company, interim report

Energy Technology Data Exchange (ETDEWEB)

Tison, R.R.; Baker, N.R.; Yudow, B.D.; Sala, D.L.; Donakowski, T.D.; Swenson, P.F.

1979-08-01

Heat-pump-centered integrated community energy systems are energy systems for communities that provide heating, cooling, and/or other thermal energy services through the use of heat pumps. Since heat pumps primarily transfer energy from existing and otherwise probably unused sources, rather than convert it from electrical or chemical to thermal form, HP-ICES offer a significant potential for energy savings. Results of the System Development Phase of the HP-ICES Project are given. The heat-actuated (gas) heat-pump incorporated into this HP-ICES concept is under current development and demonstration. The concurrent program was redirected in September 1977 toward large-tonnage applications; it is currently focusing on 60- to 400-ton built-up systems for multi-zone applications. This study evaluates the performance of a HAHP-ICES as applied to a community of residential and commercial buildings. To permit a general assessment of the concept in non-site-specific terms, the sensitivity of the system's performance and economics to climate, community size, utility rate structures, and economic assumptions is explored. (MCW)

Experience in Modelling Nuclear Energy Systems with MESSAGE: Country Case Studies

International Nuclear Information System (INIS)

2018-01-01

Member States have recognized the increasing need to model future nuclear power scenarios in order to develop strategies for sustainable nuclear energy systems. The IAEA model for energy supply strategy alternatives and their general environmental impacts (MESSAGE) code is a tool that supports energy analysis and planning in Member States. This publication documents the experience gained on modelling and scenario analysis of nuclear energy systems (NES) using the MESSAGE code through various case studies performed by the participating Member States on evaluation and planning for nuclear energy sustainability at the regional or national level. The publication also elaborates on experience gained in modelling of global nuclear energy systems with a focus on specific aspects of collaboration among technology holder and technology user countries and the introduction of innovative nuclear technologies. It presents country case studies covering a variety of nuclear energy systems based on a once-through fuel cycle and a closed fuel cycle for thermal reactors, fast reactors and advanced systems. The feedback from case studies proves the analytical capabilities of the MESSAGE model and highlight the path forward for further advancements in the MESSAGE code and NES modelling.

Interacting holographic dark energy models: a general approach

Science.gov (United States)

Som, S.; Sil, A.

2014-08-01

Dark energy models inspired by the cosmological holographic principle are studied in homogeneous isotropic spacetime with a general choice for the dark energy density . Special choices of the parameters enable us to obtain three different holographic models, including the holographic Ricci dark energy (RDE) model. Effect of interaction between dark matter and dark energy on the dynamics of those models are investigated for different popular forms of interaction. It is found that crossing of phantom divide can be avoided in RDE models for β>0.5 irrespective of the presence of interaction. A choice of α=1 and β=2/3 leads to a varying Λ-like model introducing an IR cutoff length Λ -1/2. It is concluded that among the popular choices an interaction of the form Q∝ Hρ m suits the best in avoiding the coincidence problem in this model.

Engineered Geothermal Systems Energy Return On Energy Investment

Energy Technology Data Exchange (ETDEWEB)

Mansure, A J

2012-12-10

Energy Return On Investment (EROI) is an important figure of merit for assessing the viability of energy alternatives. Too often comparisons of energy systems use efficiency when EROI would be more appropriate. For geothermal electric power generation, EROI is determined by the electricity delivered to the consumer compared to the energy consumed to construct, operate, and decommission the facility. Critical factors in determining the EROI of Engineered Geothermal Systems (EGS) are examined in this work. These include the input energy embodied into the system. Embodied energy includes the energy contained in the materials, as well as, that consumed in each stage of manufacturing from mining the raw materials to assembling the finished system. Also critical are the system boundaries and value of the energy heat is not as valuable as electrical energy. The EROI of an EGS depends upon a number of factors that are currently unknown, for example what will be typical EGS well productivity, as well as, reservoir depth, temperature, and temperature decline rate. Thus the approach developed is to consider these factors as parameters determining EROI as a function of number of wells needed. Since the energy needed to construct a geothermal well is a function of depth, results are provided as a function of well depth. Parametric determination of EGS EROI is calculated using existing information on EGS and US Department of Energy (DOE) targets and is compared to the minimum EROI an energy production system should have to be an asset rather than a liability.

Theory of finite periodic systems - I: General expressions and various simple and illustrative examples

International Nuclear Information System (INIS)

Pereyra, Pedro; Castillo, Edith

2001-09-01

A comprehensive presentation of a new approach to finite periodic systems is given. The novel and general expressions obtained here, allow simple and precise calculations of various physical quantities characteristic of crystalline systems. Transmission amplitudes through n-cell multichannel quantum systems are rigorously derived. General expressions for several physical quantities are entirely expressed in terms of single-cell amplitudes and a new class of polynomials p N,n . Besides the general expressions, we study some superlattice properties as the band structure and its relation with the phase coherence phenomena, the level density and the Kronig-Penney model as its continuous espectrum limit. Bandstructure tailoring, optical multilayer systems, resonant energies and functions and channel-mixing effects in multichannel transport process are also analysed in the light of the new approach. (author)

Optimal unit sizing of a hybrid renewable energy system for isolated applications; Optimalite des elements d'un systeme decentralise de production d'energie electrique

Energy Technology Data Exchange (ETDEWEB)

Morales, D

2006-07-15

In general, the methods used to conceive a renewable energy production system overestimate the size of the generating units. These methods increase the investment cost and the production cost of energy. The work presented in this thesis proposes a methodology to optimally size a renewable energy system.- This study shows that the classic approach based only on a long term analysis of system's behaviour is not sufficient and a complementary methodology based on a short term analysis is proposed. A numerical simulation was developed in which the mathematical models of the solar panel, the wind turbines and battery are integrated. The daily average solar energy per m2 is decomposed into a series of hourly I energy values using the Collares-Pereira equations. The time series analysis of the wind speed is made using the Monte Carlo Simulation Method. The second part of this thesis makes a detailed analysis of an isolated wind energy production system. The average energy produced by the system depends on the generator's rated power, the total swept area of the wind turbine, the gearbox's transformation ratio, the battery voltage and the wind speed probability function. The study proposes a methodology to determine the optimal matching between the rated power of the permanent magnet synchronous machine and the wind turbine's rotor size. This is made taking into account the average electrical energy produced over a period of time. (author)

Summary Report of the INL-JISEA Workshop on Nuclear Hybrid Energy Systems

Energy Technology Data Exchange (ETDEWEB)

Antkowiak, M.; Ruth, M.; Boardman, R.; Bragg-Sitton, S.; Cherry, R.; Shunn, L.

2012-07-01

The Institute for Nuclear Energy Science and Technology (INEST) and the Joint Institute for Strategic Energy Analysis (JISEA) co-sponsored an international workshop to identify research topics important in advancing the potential use of hybrid systems with a specific focus on nuclear-renewable hybrid systems. The workshop included presentations ranging from energy challenges and research and development directions being pursued by nations to multiple options for hybrid systems. Those options include one that is being commercialized to other opportunities and analysis results quantifying them. The workshop also involved two breakout sessions--one focused on thermal energy management issues especially at unit-operation scale and the second focused on system operations issues including system controls, regulatory issues, technical and economic analysis, and market challenges. A discussion involving the full group focused on more general issues such as societal involvement and participation. Key criteria for selecting hybrid energy system projects and metrics for comparing them were also identified by the full group.

Energy Information Systems

Science.gov (United States)

Home > Building Energy Information Systems and Performance Monitoring (EIS-PM) Building Energy evaluate and improve performance monitoring tools for energy savings in commercial buildings. Within the and visualization capabilities to energy and facility managers. As an increasing number of

Towards the observation of Territorial Energy Systems - a geographical design approach for energy territorialisation

International Nuclear Information System (INIS)

Flety, Yann

2014-01-01

Having an effect on a system calls for a thorough knowledge of it. The main goal of this research is to provide a general framework for the interpretation of geographic information, as well as a methodological framework to understand the interrelations between territory and energy in the context of a territorial observatory. A literature review of energy planning on the one hand and spatial planning on the other reveals similar developments in the two fields, in particular in terms of decentralisation and environmental concerns. The change of geographical scale chosen for the analysis brings new possibilities for public intervention. In this context, therefore, local authorities have a key role to play in implementing energy policy goals in their planning practices. They need analysis and prospective studies, as well as basic knowledge to carry out territorial energy planning. Indeed, the socio-spatial functions (living, travelling, working, etc.) are themselves at the root of spatial layout, urban forms and settlement structures. Those functions cannot be disassociated from questions of land use and energy. So, to understand energy which is vital, ubiquitous, and responsible for the organisation of territory, a systemic approach is proposed: the Territorial Energy System. It illustrates the importance of the interactions between a territory and its energy system, and more precisely, the interdependence between energy processes and territorial ones. We propose a design approach in the context of an observatory, and more precisely conceptual models, to analyse the territory-energy interrelations, especially with a focus on semantic dimensions. This approach combines three elements: a meta-model, a light and pre-consensus domain ontology, and individual conceptual data models for each indicator. An original indicator is then used for a first ontology population: the territorial energy label. Characterising the interrelations between territory and energy is non

Correspondence between the President of the Atomic Energy Organization of Iran and the Director General

International Nuclear Information System (INIS)

1984-09-01

The document includes 5 attachments: the letter of 9 April 1984 from the President of the Atomic Energy Organization of Iran to the Director General, the letter of 11 May 1984 from the Director General to the President of the Atomic Energy Organization of Iran, the text of the telex of 27 May 1984 from the President of the Atomic Energy Organization of Iran to the Director General, the text of the telex of 28 May 1984 from the Director General to the President of the Atomic Energy Organization of Iran and the text of the telex from 30 May 1984 from the President of the Atomic Energy Organization of Iran to the Director General refering to ''Military attack on Iran's Bushehr Nuclear Power Plant''

Generalized direct Lyapunov method for the analysis of stability and attraction in general time systems

International Nuclear Information System (INIS)

Druzhinina, O V; Shestakov, A A

2002-01-01

A generalized direct Lyapunov method is put forward for the study of stability and attraction in general time systems of the following types: the classical dynamical system in the sense of Birkhoff, the general system in the sense of Zubov, the general system in the sense of Seibert, the general system with delay, and the general 'input-output' system. For such systems, with the help of generalized Lyapunov functions with respect to two filters, two quasifilters, or two filter bases, necessary and sufficient conditions for stability and attraction are obtained under minimal assumptions about the mathematical structure of the general system

An Advanced IoT-based System for Intelligent Energy Management in Buildings

Directory of Open Access Journals (Sweden)

Vangelis Marinakis

2018-02-01

Full Text Available The energy sector is closely interconnected with the building sector and integrated Information and Communication Technologies (ICT solutions for effective energy management supporting decision-making at building, district and city level are key fundamental elements for making a city Smart. The available systems are designed and intended exclusively for a predefined number of cases and systems without allowing for expansion and interoperability with other applications that is partially due to the lack of semantics. This paper presents an advanced Internet of Things (IoT based system for intelligent energy management in buildings. A semantic framework is introduced aiming at the unified and standardised modelling of the entities that constitute the building environment. Suitable rules are formed, aiming at the intelligent energy management and the general modus operandi of Smart Building. In this context, an IoT-based system was implemented, which enhances the interactivity of the buildings’ energy management systems. The results from its pilot application are presented and discussed. The proposed system extends existing approaches and integrates cross-domain data, such as the building’s data (e.g., energy management systems, energy production, energy prices, weather data and end-users’ behaviour, in order to produce daily and weekly action plans for the energy end-users with actionable personalised information.

An Advanced IoT-based System for Intelligent Energy Management in Buildings.

Science.gov (United States)

Marinakis, Vangelis; Doukas, Haris

2018-02-16

The energy sector is closely interconnected with the building sector and integrated Information and Communication Technologies (ICT) solutions for effective energy management supporting decision-making at building, district and city level are key fundamental elements for making a city Smart. The available systems are designed and intended exclusively for a predefined number of cases and systems without allowing for expansion and interoperability with other applications that is partially due to the lack of semantics. This paper presents an advanced Internet of Things (IoT) based system for intelligent energy management in buildings. A semantic framework is introduced aiming at the unified and standardised modelling of the entities that constitute the building environment. Suitable rules are formed, aiming at the intelligent energy management and the general modus operandi of Smart Building. In this context, an IoT-based system was implemented, which enhances the interactivity of the buildings' energy management systems. The results from its pilot application are presented and discussed. The proposed system extends existing approaches and integrates cross-domain data, such as the building's data (e.g., energy management systems), energy production, energy prices, weather data and end-users' behaviour, in order to produce daily and weekly action plans for the energy end-users with actionable personalised information.

An Advanced IoT-based System for Intelligent Energy Management in Buildings

Science.gov (United States)

Doukas, Haris

2018-01-01

The energy sector is closely interconnected with the building sector and integrated Information and Communication Technologies (ICT) solutions for effective energy management supporting decision-making at building, district and city level are key fundamental elements for making a city Smart. The available systems are designed and intended exclusively for a predefined number of cases and systems without allowing for expansion and interoperability with other applications that is partially due to the lack of semantics. This paper presents an advanced Internet of Things (IoT) based system for intelligent energy management in buildings. A semantic framework is introduced aiming at the unified and standardised modelling of the entities that constitute the building environment. Suitable rules are formed, aiming at the intelligent energy management and the general modus operandi of Smart Building. In this context, an IoT-based system was implemented, which enhances the interactivity of the buildings’ energy management systems. The results from its pilot application are presented and discussed. The proposed system extends existing approaches and integrates cross-domain data, such as the building’s data (e.g., energy management systems), energy production, energy prices, weather data and end-users’ behaviour, in order to produce daily and weekly action plans for the energy end-users with actionable personalised information. PMID:29462957

The generalized Q-S synchronization between the generalized Lorenz canonical form and the Roessler system

International Nuclear Information System (INIS)

Yang Yunqing; Chen Yong

2009-01-01

In this paper, we investigate the generalized Q-S synchronization between the generalized Lorenz canonical form and the Roessler system. Firstly, we transform an arbitrary generalized Lorenz system to the generalized Lorenz canonical form, and the relation between the parameter of the generalized Lorenz system and the parameter of the generalized Lorenz canonical form are shown. Secondly, we extend the scheme present by [Yan ZY. Chaos 2005;15:023902] to study the generalized Q-S synchronization between the generalized Lorenz canonical form and the Roessler system, the more general controller is obtained. By choosing different parameter in the generalized controller obtained here, without much extra effort, we can get the controller of synchronization between the Chen system and the Roessler system, the Lue system and the Roessler system, the classic Lorenz system and the Roessler system, the Hyperbolic Lorenz system and the Roessler system, respectively. Finally, numerical simulations are used to perform such synchronization and verify the effectiveness of the controller.

Decaying states as complex energy eigenvectors in generalized quantum mechanics

International Nuclear Information System (INIS)

Sudarshan, E.C.G.; Chiu, C.B.; Gorini, V.

1977-04-01

The problem of particle decay is reexamined within the Hamiltonian formalism. By deforming contours of integration, the survival amplitude is expressed as a sum of purely exponential contributions arising from the simple poles of the resolvent on the second sheet plus a background integral along a complex contour GAMMA running below the location of the poles. One observes that the time dependence of the survival amplitude in the small time region is strongly correlated to the asymptotic behaviour of the energy spectrum of the system; one computes the small time behavior of the survival amplitude for a wide variety of asymptotic behaviors. In the special case of the Lee model, using a formal procedure of analytic continuation, it is shown that a complete set of complex energy eigenvectors of the Hamiltonian can be associated with the poles of the resolvent of the background contour GAMMA. These poles and points along GAMMA correspond to the discrete and the continuum states respectively. In this context, each unstable particle is associated with a well defined object, which is a discrete generalized eigenstate of the Hamiltonian having a complex eigenvalue, with its real and negative imaginary parts being the mass and half width of the particle respectively. Finally, one briefly discusses the analytic continuation of the scattering amplitude within this generalized scheme, and notes the appearance of ''redundant poles'' which do not correspond to discrete solutions of the modified eigenvalue problem

Hybrid energy system evaluation in water supply system energy production: neural network approach

Energy Technology Data Exchange (ETDEWEB)

Goncalves, Fabio V.; Ramos, Helena M. [Civil Engineering Department, Instituto Superior Tecnico, Technical University of Lisbon, Av. Rovisco Pais, 1049-001, Lisbon (Portugal); Reis, Luisa Fernanda R. [Universidade de Sao Paulo, EESC/USP, Departamento de Hidraulica e Saneamento., Avenida do Trabalhador Saocarlense, 400, Sao Carlos-SP (Brazil)

2010-07-01

Water supply systems are large consumers of energy and the use of hybrid systems for green energy production is this new proposal. This work presents a computational model based on neural networks to determine the best configuration of a hybrid system to generate energy in water supply systems. In this study the energy sources to make this hybrid system can be the national power grid, micro-hydro and wind turbines. The artificial neural network is composed of six layers, trained to use data generated by a model of hybrid configuration and an economic simulator - CES. The reason for the development of an advanced model of forecasting based on neural networks is to allow rapid simulation and proper interaction with hydraulic and power model simulator - HPS. The results show that this computational model is useful as advanced decision support system in the design of configurations of hybrid power systems applied to water supply systems, improving the solutions in the development of its global energy efficiency.

A Neural Network Controller for Variable-Speed Variable-Pitch Wind Energy Conversion Systems Using Generalized Minimum Entropy Criterion

Directory of Open Access Journals (Sweden)

Mifeng Ren

2014-01-01

Full Text Available This paper considers the neural network controller design problem for variable pitch wind energy conversion systems (WECS with non-Gaussian wind speed disturbances in the stochastic distribution control framework. The approach here is used to directly model the unknown control law based on a fixed neural network (the number of layers and nodes in a neural network is fixed without the need to construct a separate model for the WECS. In order to characterize the randomness of the WECS, a generalized minimum entropy criterion is established to train connection weights of the neural network. For the train purpose, both kernel density estimation method and sliding window technique are adopted to estimate the PDF of tracking error and entropies. Due to the unknown process dynamics, the gradient of the objective function in a gradient-descent-type algorithm is estimated using an incremental perturbation method. The proposed approach is illustrated on a simulated WECS with non-Gaussian wind speed.

Modular Energy Storage System for Alternative Energy Vehicles

Energy Technology Data Exchange (ETDEWEB)

Thomas, Janice [Magna Electronics Inc., Auburn Hills, MI (United States); Ervin, Frank [Magna Electronics Inc., Auburn Hills, MI (United States)

2012-05-15

An electrical vehicle environment was established to promote research and technology development in the area of high power energy management. The project incorporates a topology that permits parallel development of an alternative energy delivery system and an energy storage system. The objective of the project is to develop technologies, specifically power electronics, energy storage electronics and controls that provide efficient and effective energy management between electrically powered devices in alternative energy vehicles plugin electric vehicles, hybrid vehicles, range extended vehicles, and hydrogen-based fuel cell vehicles. In order to meet the project objectives, the Vehicle Energy Management System (VEMS) was defined and subsystem requirements were obtained. Afterwards, power electronics, energy storage electronics and controls were designed. Finally, these subsystems were built, tested individually, and integrated into an electric vehicle system to evaluate and optimize the subsystems performance. Phase 1 of the program established the fundamental test bed to support development of an electrical environment ideal for fuel cell application and the mitigation of many shortcomings of current fuel cell technology. Phase 2, continued development from Phase 1, focusing on implementing subsystem requirements, design and construction of the energy management subsystem, and the integration of this subsystem into the surrogate electric vehicle. Phase 2 also required the development of an Alternative Energy System (AES) capable of emulating electrical characteristics of fuel cells, battery, gen set, etc. Under the scope of the project, a boost converter that couples the alternate energy delivery system to the energy storage system was developed, constructed and tested. Modeling tools were utilized during the design process to optimize both component and system design. This model driven design process enabled an iterative process to track and evaluate the impact

Energy Systems in the Era of Energy Vectors A Key to Define, Analyze and Design Energy Systems Beyond Fossil Fuels

CERN Document Server

Orecchini, Fabio

2012-01-01

What lies beyond the era of fossil fuels? While most answers focus on different primary energy resources, Energy Systems in the Era of Energy Vectors provides a completely new approach. Instead of providing a traditional consumption analysis of classical primary energy resources such as oil, coal, nuclear power and gas, Energy Systems in the Era of Energy Vectors describes and assesses energy technologies, markets and future strategies, focusing on their capacity to produce, exchange, and use energy vectors. Special attention is given to the renewable energy resources available in different areas of the world and made exploitable by the integration of energy vectors in the global energy system. Clear definitions of energy vectors and energy systems are used as the basis for a complete explanation and assessment of up-to-date, available technologies for energy resources, transport and storage systems, conversion and use. The energy vectors scheme allows the potential realisation of a worldwide sustainable ener...

User's manual for computer code SOLTES-1 (simulator of large thermal energy systems)

International Nuclear Information System (INIS)

Fewell, M.E.; Grandjean, N.R.; Dunn, J.C.; Edenburn, M.W.

1978-09-01

SOLTES simulates the steady-state response of thermal energy systems to time-varying data such as weather and loads. Thermal energy system models of both simple and complex systems can easily be modularly constructed from a library of routines. These routines mathematically model solar collectors, pumps, switches, thermal energy storage, thermal boilers, auxiliary boilers, heat exchangers, extraction turbines, extraction turbine/generators, condensers, regenerative heaters, air conditioners, heating and cooling of buildings, process vapor, etc.; SOLTES also allows user-supplied routines. The analyst need only specify fluid names to obtain readout of property data for heat-transfer fluids and constants that characterize power-cycle working fluids from a fluid property data bank. A load management capability allows SOLTES to simulate total energy systems that simultaneously follow heat and power loads and demands. Generalized energy accounting is available, and values for system performance parameters may be automatically determined by SOLTES. Because of its modularity and flexibility, SOLTES can be used to simulate a wide variety of thermal energy systems such as solar power/total energy, fossil fuel power plants/total energy, nuclear power plants/total energy, solar energy heating and cooling, geothermal energy, and solar hot water heaters

Biomass in a sustainable energy system

International Nuclear Information System (INIS)

Boerjesson, Paal

1998-04-01

In this thesis, aspects of an increase in the utilization of biomass in the Swedish energy system are treated. Modern bioenergy systems should be based on high energy and land use efficiency since biomass resources and productive land are limited. The energy input, including transportation, per unit biomass produced is about 4-5% for logging residues, straw and short rotation forest (Salix). Salix has the highest net energy yield per hectare among the various energy crops cultivated in Sweden. The CO 2 emissions from the production and transportation of logging residues, straw and Salix, are equivalent to 2-3% of those from a complete fuel-cycle for coal. Substituting biomass for fossil fuels in electricity and heat production is, in general, less costly and leads to a greater CO 2 reduction per unit biomass than substituting biomass derived transportation fuels for petrol or diesel. Transportation fuels produced from cellulosic biomass provide larger and less expensive CO 2 emission reductions than transportation fuels from annual crops. Swedish CO 2 emissions could be reduced by about 50% from the present level if fossil fuels are replaced and the energy demand is unchanged. There is a good balance between potential regional production and utilization of biomass in Sweden. Future biomass transportation distances need not be longer than, on average, about 40 km. About 22 TWh electricity could be produced annually from biomass in large district heating systems by cogeneration. Cultivation of Salix and energy grass could be utilized to reduce the negative environmental impact of current agricultural practices, such as the emission of greenhouse gases, nutrient leaching, decreased soil fertility and erosion, and for the treatment of municipal waste and sludge, leading to increased recirculation of nutrients. About 20 TWh biomass could theoretically be produced per year at an average cost of less than 50% of current production cost, if the economic value of these

Biomass in a sustainable energy system

Energy Technology Data Exchange (ETDEWEB)

Boerjesson, Paal

1998-04-01

In this thesis, aspects of an increase in the utilization of biomass in the Swedish energy system are treated. Modern bioenergy systems should be based on high energy and land use efficiency since biomass resources and productive land are limited. The energy input, including transportation, per unit biomass produced is about 4-5% for logging residues, straw and short rotation forest (Salix). Salix has the highest net energy yield per hectare among the various energy crops cultivated in Sweden. The CO{sub 2} emissions from the production and transportation of logging residues, straw and Salix, are equivalent to 2-3% of those from a complete fuel-cycle for coal. Substituting biomass for fossil fuels in electricity and heat production is, in general, less costly and leads to a greater CO{sub 2} reduction per unit biomass than substituting biomass derived transportation fuels for petrol or diesel. Transportation fuels produced from cellulosic biomass provide larger and less expensive CO{sub 2} emission reductions than transportation fuels from annual crops. Swedish CO{sub 2} emissions could be reduced by about 50% from the present level if fossil fuels are replaced and the energy demand is unchanged. There is a good balance between potential regional production and utilization of biomass in Sweden. Future biomass transportation distances need not be longer than, on average, about 40 km. About 22 TWh electricity could be produced annually from biomass in large district heating systems by cogeneration. Cultivation of Salix and energy grass could be utilized to reduce the negative environmental impact of current agricultural practices, such as the emission of greenhouse gases, nutrient leaching, decreased soil fertility and erosion, and for the treatment of municipal waste and sludge, leading to increased recirculation of nutrients. About 20 TWh biomass could theoretically be produced per year at an average cost of less than 50% of current production cost, if the economic

Annual report 2005 General Direction of the Energy and raw materials

International Nuclear Information System (INIS)

2005-01-01

This 2005 annual report of the DGEMP (General Direction of the Energy and the raw Materials), takes stock on the energy bill and accounting of the France. The first part presents the electric power, natural gas and raw materials market in France. The second part is devoted to the diversification of the energy resources with a special attention to the renewable energies and the nuclear energy. The third part discusses the energy and raw materials prices and the last part presents the international cooperation in the energy domain. (A.L.B.)

Addressing the main challenges of energy security in the twenty-first century – Contributions of the conferences on Sustainable Development of Energy, Water and Environment Systems

DEFF Research Database (Denmark)

Markovska, Natasa; Duić, Neven; Mathiesen, Brian Vad

2016-01-01

Climate change and fossil fuel reserve depletion both pose challenges for energy security and for wellbeing in general. The top ten among them include: Decarbonising the world economy; Enhancing the energy efficiency and energy savings in buildings; Advancing the energy technologies; Moving towards...... energy systems based on variable renewables; Electrifying the transport and some industrial processes; Liberalizing and extending the energy markets; Integrating energy sectors to Smart Energy Systems; Making the cities and communities smart; Diversifying the energy sources; and Building more...

Energy Efficient Mobile Operating Systems

OpenAIRE

Muhammad Waseem

2013-01-01

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

LCA of Energy Systems

DEFF Research Database (Denmark)

Laurent, Alexis; Espinosa Martinez, Nieves; Hauschild, Michael Zwicky

2018-01-01

Energy systems are essential in the support of modern societies’ activities, and can span a wide spectrum of electricity and heat generation systems and cooling systems. Along with their central role and large diversity, these systems have been demonstrated to cause serious impacts on human health...... , ecosystems and natural resources. Over the past two decades, energy systems have thus been the focus of more than 1000 LCA studies, with the aim to identify and reduce these impacts. This chapter addresses LCA applications to energy systems for generation of electricity and heat . The chapter gives insight...

Income- and energy-taxation for redistribution in general equilibrium

International Nuclear Information System (INIS)

FitzRoy, F.R.

1993-01-01

In a 3-factor General Equilibrium (GE)-model with a continuum of ability, the employed choose optimal labour supply, and equilibrium unemployment is determined by benefits funded by wage- and energy-taxes. Aggregate labour and the net wage may increase or decrease with taxation (and unemployment), and conditions for a reduction in redistributive wage-taxes to be Pareto-improving are derived. A small energy tax always raises the net wage, providing the wage tax is reduced to maintain constant employment and a balanced budget. High ability households prefer higher energy taxes when externalities are uniformly distributed and non-distorting. (author)

Social learning and energy systems: implementing a high energy saving goal in a residential area

Energy Technology Data Exchange (ETDEWEB)

Glad, Wiktoria (Linkoeping University, Department of Thematic Studies (Sweden))

2011-07-01

Generally, retrofitting existing housing stock is considered the area with the most energy-efficiency potential, since buildings last a long time and turnover is slow. This paper presents practice- based research into social learning in the domain of new energy systems in existing dwellings. A case study from Sweden is presented and analysed in relation to social learning. The methodology and data collection are guided by a 'thick description' approach that acknowledges the importance of putting human action in context. The theoretical framework chosen also stresses contexts, using social learning concepts from social shaping of technology (SST) theory. The energy systems as used and managed by professionals and tenants of this retrofitted housing project are the focus. I analyse three connected systems, i.e., the electricity, heating, and hot water system, all parts of a novel individual metering and debiting system installed during the retrofit. An overall goal of the retrofit was to reduce energy demand by 52 % which was achieved but not by the measures invested in. The delivery, metering, and debiting of the energy services are managed in-house by the housing company, but it is up to the tenants to reduce their energy demand. The housing company's technology and implementation policies were ambivalent and evolved in response to the needs of professionals and tenants. Statistics from the property owner's evaluation indicate that the project achieved its goal, but the figures hide that it might have been due to fewer flats, new tenants and new use of buildings

Kinetic energy storage system

Energy Technology Data Exchange (ETDEWEB)

Jaeggi, M.; Folini, P.

1983-09-03

A flywheel system for the purpose of energy storage in decentral solar- or wind energy plants is introduced. The system comprises a rotor made out of plastic fibre, a motor/generator serving as electro-mechanical energy converter and a frequency-voltage transformer serving as electric adapter. The storable energy quantity amounts to several kWh.

A study on the improvement of the legal system concerning Korean Atomic Energy Act

International Nuclear Information System (INIS)

Yoo, Il Un; Jung, Jong Hak; Kim, Jae Ho; Moon, Jong Wook; Kim, In Sub

1998-03-01

Cause-effect analysis, adjustment, and generalization of the current atomic energy act are contents of this research. These are to be based on the legal theory. Analysis of the current atomic energy act from the viewpoint of constitutional law and administrative law. Review of the other domestic legal systems which have similar problems as the atomic energy act has. Inquiry about the operation of nuclear legal systems of foreign nations

A study on the improvement of the legal system concerning Korean Atomic Energy Act

Energy Technology Data Exchange (ETDEWEB)

Yoo, Il Un; Jung, Jong Hak; Kim, Jae Ho; Moon, Jong Wook; Kim, In Sub [Chungnam National Univ., Taejon (Korea, Republic of)

1998-03-15

Cause-effect analysis, adjustment, and generalization of the current atomic energy act are contents of this research. These are to be based on the legal theory. Analysis of the current atomic energy act from the viewpoint of constitutional law and administrative law. Review of the other domestic legal systems which have similar problems as the atomic energy act has. Inquiry about the operation of nuclear legal systems of foreign nations.

Cost/benefit comparison of thermal solar energy systems in Switzerland

International Nuclear Information System (INIS)

Suter, J.M.

1991-10-01

A comparison is made between thermal solar energy systems of different size for five different applications in the three main climatic zones in Switzerland. Conventional ways of energy conservation are also included in the comparison. A cost/benefit ratio is calculated for each system. The investment is used as a cost indicator whereas the useful solar heat or the conventional energy saving is chosen as benefit. It is shown that the most systems sold today in Switzerland - combined hot water and space heating systems for single family houses - have the poorest cost/benefit ratio among all systems considered in the analysis. Four applications with more favourable cost/benefit ratio are identified. Large systems have generally a better cost/benefit ratio than smaller ones, although the total investment is higher. Photovoltaics is even less favourable than all thermal systems considered. The large scale penetration of technologies with good cost/benefit ratio lies in the public interest. Supporting activities should consider the priority set by the cost/benefit ratio. (author) 1 fig., 14 refs

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.

Rebound effect of improved energy efficiency for different energy types: A general equilibrium analysis for China

International Nuclear Information System (INIS)

Lu, Yingying; Liu, Yu; Zhou, Meifang

2017-01-01

This paper explores the rebound effect of different energy types in China based on a static computable general equilibrium model. A one-off 5% energy efficiency improvement is imposed on five different types of energy, respectively, in all the 135 production sectors in China. The rebound effect is measured both on the production level and on the economy-wide level for each type of energy. The results show that improving energy efficiency of using electricity has the largest positive impact on GDP among the five energy types. Inter-fuel substitutability does not affect the macroeconomic results significantly, but long-run impact is usually greater than the short-run impact. For the exports-oriented sectors, those that are capital-intensive get big negative shock in the short run while those that are labour-intensive get hurt in the long run. There is no “backfire” effect; however, improving efficiency of using electricity can cause negative rebound, which implies that improving the energy efficiency of using electricity might be a good policy choice under China's current energy structure. In general, macro-level rebound is larger than production-level rebound. Primary energy goods show larger rebound effect than secondary energy goods. In addition, the paper points out that the policy makers in China should look at the rebound effect in the long term rather than in the short term. The energy efficiency policy would be a good and effective policy choice for energy conservation in China when it still has small inter-fuel substitution. - Highlights: • Primary energy goods show larger rebound effect than secondary energy goods. • Improving efficiency of using electricity can cause negative rebound. • The energy efficiency policy would be an effective policy choice for China. • Policy-makers should consider the rebound effect in the longer term.

Environment taxation and greenhouse gases (general tax on energy polluting activities and emissions trading)

International Nuclear Information System (INIS)

Parayre, P.; Bruhnes, P.; Huglo, Ch.

2000-12-01

This document brings together 11 expert testimonies about the French general tax on polluting activities (GTPA). Content: 1 - the GTPA today and in 2001: the first year GTPA, the GTPA 2001 in the water sector, the everyday formal procedures linked with GTPA, the contentious aspects of GTPA; 2 - the eco-tax or energy-GTPA: European framework of energy products taxing, enforcement and implementation of the energy-GTPA in France; 3 - the negotiable emission permits: negotiable permits for companies with a strong energy intensity, functioning of emission permits in a global strategy, the position of the European Commission about negotiable permits and the perspectives in this domain at the community level; 4 - towards a reduction of greenhouse gases: the Goeteborg protocol, the consequences of La Haye's COP6, the position of a type-sector, an efficient system for the abatement of greenhouse gases by the producing sector. (J.S.)

Integrating renewable energy into general practice : final report

Energy Technology Data Exchange (ETDEWEB)

NONE

2008-12-01

This feasibility study was conducted to determine the viability of integrating solar thermal residential domestic hot water systems and community ground source heating and air conditioning within low-income housing projects in Toronto. The study examined the organizational changes needed to incorporate renewable energy systems for small-scale district and individual homes. The study was conducted on behalf of Habitat for Humanity (HFHT). Results of the study showed that the most significant benefits of integrating renewable energy systems will be the elimination of fossil fuel usage; reductions in home operating costs for partner families; and the potential for leveraging increased sponsorship funds. A geoexchange heating, ventilation and air conditioning (HVAC) system was recommended for the new HFHT headquarters as well as for future housing projects. It was concluded that HFHT should prepare for increased integration of renewable energy technologies as capital costs decrease and greater financial incentives become available. 15 tabs., 3 figs.

The use of a running wheel to measure activity in rodents: relationship to energy balance, general activity, and reward.

Science.gov (United States)

Novak, Colleen M; Burghardt, Paul R; Levine, James A

2012-03-01

Running wheels are commonly employed to measure rodent physical activity in a variety of contexts, including studies of energy balance and obesity. There is no consensus on the nature of wheel-running activity or its underlying causes, however. Here, we will begin by systematically reviewing how running wheel availability affects physical activity and other aspects of energy balance in laboratory rodents. While wheel running and physical activity in the absence of a wheel commonly correlate in a general sense, in many specific aspects the two do not correspond. In fact, the presence of running wheels alters several aspects of energy balance, including body weight and composition, food intake, and energy expenditure of activity. We contend that wheel-running activity should be considered a behavior in and of itself, reflecting several underlying behavioral processes in addition to a rodent's general, spontaneous activity. These behavioral processes include defensive behavior, predatory aggression, and depression- and anxiety-like behaviors. As it relates to energy balance, wheel running engages several brain systems-including those related to the stress response, mood, and reward, and those responsive to growth factors-that influence energy balance indirectly. We contend that wheel-running behavior represents factors in addition to rodents' tendency to be physically active, engaging additional neural and physiological mechanisms which can then independently alter energy balance and behavior. Given the impact of wheel-running behavior on numerous overlapping systems that influence behavior and physiology, this review outlines the need for careful design and interpretation of studies that utilize running wheels as a means for exercise or as a measurement of general physical activity. Copyright © 2012 Elsevier Ltd. All rights reserved.

Contribution of safety issues to public perceptions of energy systems

International Nuclear Information System (INIS)

Otway, H.J.; Thomas, K.

1978-01-01

Public opposition is an important consideration for those responsible for energy planning; however, the formulation of socially viable policies requires an understanding of the reasons for this opposition. An attitude model was applied to identify the underlying determinants of public perceptions of five energy systems: nuclear, coal, oil, solar and hydro. Empirical results (heterogeneous sample of the general public, N = 224) are reported in which these energy systems were found to be perceived in terms of four basic dimensions: psychological aspects; economic benefits; socio-political implications; environmental and physical safety issues. For the total sample, safety issues made an appreciable contribution to attitudes toward all of the systems except nuclear energy, where it was not significant. A differential analysis of two sub-samples, those respondents PRO and CON nuclear energy, showed that benefits and safety issues were important determinants of PRO attitudes while CON attitudes were primarily due to psychological aspects and concerns about personal and political power. The role of technical information in the formation of public attitudes toward technological policies is discussed

ASAS centennial paper: net energy systems for beef cattle--concepts, application, and future models.

Science.gov (United States)

Ferrell, C L; Oltjen, J W

2008-10-01

Development of nutritional energetics can be traced to the 1400s. Lavoisier established relationships among O(2) use, CO(2) production and heat production in the late 1700s, and the laws of thermodynamics and law of Hess were discovered during the 1840s. Those discoveries established the fundamental bases for nutritional energetics and enabled the fundamental entity ME = retained energy + heat energy to be established. Objectives became: 1) to establish relationships between gas exchange and heat energy, 2) to devise bases for evaluation of foods that could be related to energy expenditures, and 3) to establish causes of energy expenditures. From these endeavors, the basic concepts of energy partitioning by animals were developed, ultimately resulting in the development of feeding systems based on NE concepts. The California Net Energy System, developed for finishing beef cattle, was the first to be based on retained energy as determined by comparative slaughter and the first to use 2 NE values (NE(m) and NE(g)) to describe feed and animal requirements. The system has been broadened conceptually to encompass life cycle energy requirements of beef cattle and modified by the inclusion of numerous adjustments to address factors known to affect energy requirements and value of feed to meet those needs. The current NE system remains useful but is empirical and static in nature and thus fails to capture the dynamics of energy utilization by diverse animals as they respond to changing environmental conditions. Consequently, efforts were initiated to develop dynamic simulation models that captured the underlying biology and thus were sensitive to variable genetic and environmental conditions. Development of a series of models has been described to show examples of the conceptual evolution of dynamic, mechanistic models and their applications. Generally with each new system, advances in prediction accuracy came about by adding new terms to conceptually validated models

Fiscal 1976 Sunshine Project result report. Research on solar energy utilization systems (total system); 1976 nendo taiyo energy riyo system chosa kenkyu seika hokokusho. Total system

Energy Technology Data Exchange (ETDEWEB)

NONE

1977-03-01

For every solar energy utilization field, its background, feasibility, impact in practical use, and R and D policy in Japan were studied. Heating and hot water supply by solar energy are already practical because of less technical problems and reasonable profitability, and cooling is also practical as far as a technical viewpoint. At present, the technical level of solar heat power generation is in the stage of basic technology, however, in the future, development of economically reasonable systems will be demanded as well as establishment of its technology. The most difficult problem for realizing practical solar cell power generation systems is cost reduction. It is also another problem that a big demand of Si for solar cells further exceeds the current yield of Si in a semiconductor industry. A small-scale hybrid solar cell power generation system applicable to the roof of general residences is already feasible. Although a solar furnace is still poor in application to industrial fields, it is expected as the leading part for a future solar heat chemical industry. (NEDO)

Proceedings of the 3. General Congress on Nuclear Energy. v. 9

International Nuclear Information System (INIS)

1990-01-01

The Proceedings of the 3. General Congress on Nuclear Energy (CGEN), present about 200 contributed papers. The topics covered by the meeting are: reactor physics and operation; risk analysis, safety analysis, nuclear power plants construction; thermohydraulics; nuclear power plants control and instrumentation; equipment and system design, radioactive management; fuel cycle; design and fabrication of fuel elements, science and technology materials; instrumentation for radiation detection and dosimetry; shielding, radiation protection, licensing, safeguards, social and environmental impacts; radioisotopes production and application; radiochemistry, radioecology; nuclear medicine and radiobiology. In this volume the contributed papers emphasize the topics shielding, radiation protection, licensing, safeguards and social and environmental impacts. (M.I.A.)

Comparative risk perception: how the public perceives the risks and benefits of energy systems

Energy Technology Data Exchange (ETDEWEB)

Thomas, K [Open Univ., Milton Keynes (UK)

1981-04-30

The view of risk perception adopted in this paper focuses on how individuals define, and hence feel about, the outcomes of a risk issue. Perception of risk is seen as encompassing a variety of attributes of a risk issue including wider beliefs that permit a risk benefit trade-off. A survey of beliefs and attitudes of the general public toward the use of various energy systems (coal, oil, hydro, solar and nuclear energy) was carried out in Austria at a time of increasing concern with energy strategies and the controversy surrounding Austria's first nuclear energy plant. The results are analysed. In general, energy systems were found to be associated with only environmental risk; however, nuclear energy was an exception in that the public, whether in favour of nuclear energy or against, believed that it is also associated with psychological and physical risk. It was also found that the policy makers underestimated the public's negative feelings about the psychological risk dimension and their belief in its association with nuclear energy.

Comparative risk perception: how the public perceives the risks and benefits of energy systems

International Nuclear Information System (INIS)

Thomas, K.

1981-01-01

The view of risk perception adopted in this paper focuses on how individuals define, and hence feel about, the outcomes of a risk issue. Perception of risk is seen as encompassing a variety of attributes of a risk issue including wider beliefs that permit a risk benefit trade-off. A survey of beliefs and attitudes of the general public toward the use of various energy systems (coal, oil, hydro, solar and nuclear energy) was carried out in Austria at a time of increasing concern with energy strategies and the controversy surrounding Austria's first nuclear energy plant. The results are analysed. In general, energy systems were found to be associated with only environmental risk; however, nuclear energy was an exception in that the public, whether in favour of nuclear energy or against, believed that it is also associated with psychological and physical risk. It was also found that the policy makers underestimated the public's negative feelings about the psychological risk dimension and their belief in its association with nuclear energy. (author)

Moving energies as first integrals of nonholonomic systems with affine constraints

Science.gov (United States)

Fassò, Francesco; García-Naranjo, Luis C.; Sansonetto, Nicola

2018-03-01

In nonholonomic mechanical systems with constraints that are affine (linear nonhomogeneous) functions of the velocities, the energy is typically not a first integral. It was shown in Fassò and Sansonetto (2016 J. Nonlinear Sci. 26 519-44) that, nevertheless, there exist modifications of the energy, called there moving energies, which under suitable conditions are first integrals. The first goal of this paper is to study the properties of these functions and the conditions that lead to their conservation. In particular, we enlarge the class of moving energies considered in Fassò and Sansonetto (2016 J. Nonlinear Sci. 26 519-44). The second goal of the paper is to demonstrate the relevance of moving energies in nonholonomic mechanics. We show that certain first integrals of some well known systems (the affine Veselova and LR systems), which had been detected on a case-by-case way, are instances of moving energies. Moreover, we determine conserved moving energies for a class of affine systems on Lie groups that include the LR systems, for a heavy convex rigid body that rolls without slipping on a uniformly rotating plane, and for an n-dimensional generalization of the Chaplygin sphere problem to a uniformly rotating hyperplane.

Energy System Analysis of Large-Scale Integration of Wind Power

International Nuclear Information System (INIS)

Lund, Henrik

2003-11-01

The paper presents the results of two research projects conducted by Aalborg University and financed by the Danish Energy Research Programme. Both projects include the development of models and system analysis with focus on large-scale integration of wind power into different energy systems. Market reactions and ability to exploit exchange on the international market for electricity by locating exports in hours of high prices are included in the analyses. This paper focuses on results which are valid for energy systems in general. The paper presents the ability of different energy systems and regulation strategies to integrate wind power, The ability is expressed by three factors: One factor is the degree of electricity excess production caused by fluctuations in wind and CHP heat demands. The other factor is the ability to utilise wind power to reduce CO 2 emission in the system. And the third factor is the ability to benefit from exchange of electricity on the market. Energy systems and regulation strategies are analysed in the range of a wind power input from 0 to 100% of the electricity demand. Based on the Danish energy system, in which 50 per cent of the electricity demand is produced in CHP, a number of future energy systems with CO 2 reduction potentials are analysed, i.e. systems with more CHP, systems using electricity for transportation (battery or hydrogen vehicles) and systems with fuel-cell technologies. For the present and such potential future energy systems different regulation strategies have been analysed, i.e. the inclusion of small CHP plants into the regulation task of electricity balancing and grid stability and investments in electric heating, heat pumps and heat storage capacity. Also the potential of energy management has been analysed. The results of the analyses make it possible to compare short-term and long-term potentials of different strategies of large-scale integration of wind power

Economic Impacts of Future Changes in the Energy System - National Perspectives

DEFF Research Database (Denmark)

Glynn, James; Fortes, Patrícia; Krook-Riekkola, Anna

2015-01-01

climate change. This chapter summarises modelling methodologies developed in the ETSAP community to assess economic impacts of decarbonising energy systems at a national level. The preceding chapter focuses on a global perspective. The modelling studies outlined here show that burden sharing rules...... and national revenue recycling schemes for carbon tax are critical for the long-term viability of economic growth and equitable engagement on combating climate change. Traditional computable general equilibrium models and energy systems models solved in isolation can misrepresent the long run carbon cost...

Membrane heat exchanger in HVAC energy recovery systems, systems energy analysis

Energy Technology Data Exchange (ETDEWEB)

Nasif, M. [School of Mechanical and Manufacturing Engineering, The University of New South Wales, Sydney, NSW 2052 (Australia); Opus International Consultants (New Zealand); AL-Waked, R. [Mechanical Engineering Department, Prince Mohammad Bin Fahd University (PMU), P.O. Box 1614, AlKhobar 31952 (Saudi Arabia); Morrison, G. [School of Mechanical and Manufacturing Engineering, The University of New South Wales, Sydney, NSW 2052 (Australia); Behnia, M. [School of Aerospace, Mechanical and Mechatronic Engineering, University of Sydney, NSW 2006 (Australia)

2010-10-15

The thermal performance of an enthalpy/membrane heat exchanger is experimentally investigated. The heat exchanger utilizes a 60gsm Kraft paper as the heat and moisture transfer surface for HVAC energy recovery. The heat exchanger sensible, latent and total effectiveness have been determined through temperature and moisture content measurements. The annual energy consumption of an air conditioner coupled with an enthalpy/membrane heat exchanger is also studied and compared with a conventional air conditioning cycle using in-house modified HPRate software. The heat exchanger effectiveness are used as thermal performance indicators and incorporated in the modified software. Energy analysis showed that an air conditioning system coupled with a membrane heat exchanger consumes less energy than a conventional air conditioning system in hot and humid climates where the latent load is high. It has been shown that in humid climate a saving of up to 8% in annual energy consumption can be achieved when membrane heat exchanger is used instead of a conventional HVAC system. (author)

Smart Energy Systems and Energy Transition

International Nuclear Information System (INIS)

Duic, N.

2016-01-01

Transition to decarbonized energy systems is becoming more attractive with fall of investment costs of renewables and volatile prices and political insecurity of fossil fuels. Improving energy efficiency, especially of buildings and transport, is important, but due to long life of buildings, it will be a slow way of decarbonization. The renewable energy resources are bountiful, especially wind and solar, while integrating them into current energy systems is proving to be a challenge. Solar has reached grid parity making it cheapest electricity source for retail customers in most of the World, creating new prosumer markets. It has started to reach cost parity in sunny countries, and soon solar energy will be cheapest everywhere. The limit of cheap and easy integration for wind is around 20% of yearly electricity generation, while a combined wind and solar may reach 30%. Going any further asks for implementation of completely free energy markets (involving day ahead, intraday and various reserve and ancillary services markets), demand response, coupling of wholesale and retail energy prices, and it involves integration between electricity, heat, water and transport systems. The cheapest and simplest way of increasing further the penetration of renewables is integrating power and heating/cooling systems through the use of district heating and cooling (which may be centrally controlled and may have significant heat storage capacity), since power to heat technologies are excellent for demand response. District cooling is of particular importance to historic cities that want to remove split systems from their facades. In countries with low heat demand water supply system may be used to increase the penetration of renewables, by using water at higher potential energy as storage media, or in dry climates desalination and stored water may be used for those purposes, and reversible hydro may be used as balancing technology. Electrification of personal car transport allows

Charge Energy Transport in Hopping Systems with Rapidly Decreasing Density of States

Science.gov (United States)

Mendels, Dan; Organic Electronics Group Technion Team

2014-03-01

An accurate description of the carrier hopping topology in the energy domain of hopping systems incorporating a rapidly decreasing density of states and the subsequent energetic position of these systems' so called effective conduction band is crucial for rationalizing and quantifying these systems' thermo-electric properties, doping related phenomena and carrier gradient effects such as the emergence of the General Einstein Relation under degenerate conditions. Additionally, as will be shown, the 'mobile' carriers propagating through the system can have excess energies reaching 0.3eV above the system quasi-Fermi energy. Hence, since these mobile carriers are most prone to reach systems interfaces and interact with oppositely charged carriers, their excess energy should be considered in determining the efficiencies of energy dependent processes such as carrier recombination and exciton dissociation. In light of the stated motivations, a comprehensive numerical and analytical study of the topology of hopping in the energetic density of such systems (i.e. the statistics regarding which energy values carriers visit most and in what manner) was implemented and the main statistical features of the hopping process that determine the position in energy of the system's effective conduction band were distilled. The obtained results also help shed light on yet to be elucidated discrepancies between predictions given by the widely employed transport energy concept and Monte Carlo simulations.

General Logic-Systems and Consequence Operators

OpenAIRE

Herrmann, Robert A.

2005-01-01

In this paper, general logic-systems are investigated. It is shown that there are infinitely many finite consequence operators defined on a fixed language L that cannot be generated from a finite logic-system. It is shown that a set map is a finite consequence operator iff it is defined by a general logic-system.

Energy Systems Integration News | Energy Systems Integration Facility |

Science.gov (United States)

determine how well a solar photovoltaic (PV) system with battery energy storage can provide backup power to . These analyses will result in a design guide for climate-specific sizing of the system. NREL's Erfan , feasibility, and operational analyses for photovoltaic and concentrating solar power generation projects

Energy Savings Forecast of Solid-State Lighting in General Illumination Applications

Energy Technology Data Exchange (ETDEWEB)

Penning, Julie [Navigant Consulting Inc., Washington, DC (United States); Stober, Kelsey [Navigant Consulting Inc., Washington, DC (United States); Taylor, Victor [Navigant Consulting Inc., Washington, DC (United States); Yamada, Mary [Navigant Consulting Inc., Washington, DC (United States)

2016-09-01

The DOE report, Energy Savings Forecast of Solid-State Lighting in General Illumination Applications, is a biannual report which models the adoption of LEDs in the U.S. general-lighting market, along with associated energy savings, based on the full potential DOE has determined to be technically feasible over time. This version of the report uses an updated 2016 U.S. lighting-market model that is more finely calibrated and granular than previous models, and extends the forecast period to 2035 from the 2030 limit that was used in previous editions.

The Smart Energy System

DEFF Research Database (Denmark)

Jurowetzki, Roman; Dyrelund, Anders; Hummelmose, Lars

Copenhagen Cleantech Cluster has launched a new report, which provides an overview of Danish competencies relating to smart energy systems. The report, which is based on a questionnaire answered by almost 200 companies working with smart energy as well as a number of expert interviews, focuses on...... production, large scale solar heat, fuel cells, heat storage, waste incineration, among others, the report draws a picture of Denmark as a research and development hub for smart energy system solutions.......Copenhagen Cleantech Cluster has launched a new report, which provides an overview of Danish competencies relating to smart energy systems. The report, which is based on a questionnaire answered by almost 200 companies working with smart energy as well as a number of expert interviews, focuses...... on the synergies which are obtained through integration of the district heating and district cooling, gas, and electricity grid into a single smart energy system. Besides documenting the technology and innovation strengths that Danish companies possess particularly relating to wind, district heating, CHP...

Generalized Cross-Gramian for Linear Systems

DEFF Research Database (Denmark)

Shaker, Hamid Reza

2012-01-01

The cross-gramian is a well-known matrix with embedded controllability and observability information. The cross-gramian is related to the Hankel operator and the Hankel singular values of a linear square system and it has several interesting properties. These properties make the cross...... square symmetric systems, the ordinary cross-gramian does not exist. To cope with this problem, a new generalized cross-gramian is introduced in this paper. In contrast to the ordinary cross-gramian, the generalized cross-gramian can be easily obtained for general linear systems and therefore can be used...

Energy spectra of odd nuclei in the generalized model

Directory of Open Access Journals (Sweden)

I. O. Korzh

2015-04-01

Full Text Available Based on the generalized nuclear model, energy spectra of the odd nuclei of such elements as 25Mg, 41K, and 65Cu are determined, and the structure of wave functions of these nuclei in the excited and normal states is studied. High quality in determining the energy spectra is possible due to the accurate calculations of all elements of the energy matrix. It is demonstrated that the structure of the wave functions so determined provides the possibility to more accurately select the nuclear model and the method for calculating the nucleon cross-sections of the inelastic scattering of nucleons by odd nuclei.

Smart energy management system

Science.gov (United States)

Desai, Aniruddha; Singh, Jugdutt

2010-04-01

Peak and average energy usage in domestic and industrial environments is growing rapidly and absence of detailed energy consumption metrics is making systematic reduction of energy usage very difficult. Smart energy management system aims at providing a cost-effective solution for managing soaring energy consumption and its impact on green house gas emissions and climate change. The solution is based on seamless integration of existing wired and wireless communication technologies combined with smart context-aware software which offers a complete solution for automation of energy measurement and device control. The persuasive software presents users with easy-to-assimilate visual cues identifying problem areas and time periods and encourages a behavioural change to conserve energy. The system allows analysis of real-time/statistical consumption data with the ability to drill down into detailed analysis of power consumption, CO2 emissions and cost. The system generates intelligent projections and suggests potential methods (e.g. reducing standby, tuning heating/cooling temperature, etc.) of reducing energy consumption. The user interface is accessible using web enabled devices such as PDAs, PCs, etc. or using SMS, email, and instant messaging. Successful real-world trial of the system has demonstrated the potential to save 20 to 30% energy consumption on an average. Low cost of deployment and the ability to easily manage consumption from various web enabled devices offers gives this system a high penetration and impact capability offering a sustainable solution to act on climate change today.

Constitutional compatibility of energy systems

International Nuclear Information System (INIS)

Rossnagel, A.

1983-01-01

The paper starts from the results of the Enquiry Commission on 'Future Nuclear Energy Policy' of the 8th Federal German Parliament outlining technically feasible energy futures in four 'pathways'. For the purpose of the project, which was to establish the comparative advantages and disadvantages of different energy systems, these four scenarios were reduced to two alternatives: cases K (= nuclear energy) and S (= solar energy). The question to Ge put is: Which changes within our legal system will be ushered in by certain technological developments and how do these changes relate to the legal condition intended so far. Proceeding in this manner will not lead to the result of a nuclear energy system or a solar energy system being in conformity or in contradiction with the constitutional law, but will provide a catalogue of implications orientated to the aims of legal standards: a person deciding in favour of a nuclear energy system or a solar energy system supports this or that development of constitutional policy, and a person purishing this or that aim of legal policy should be consistent and decide in favour of this or that energy system. The investigation of constitutional compatibility leads to the question what effects different energy systems will have on the forms of political intercourse laid down in the constitutional law, which are orientated to models of a liberal constitutional tradition of citizens. (orig./HSCH) [de

Environmentally-adapted local energy systems

Energy Technology Data Exchange (ETDEWEB)

Moe, N; Oefverholm, E [NUTEK, Stockholm (Sweden); Andersson, Owe [EKAN Gruppen (Sweden); Froste, H [Swedish Environmental Protection Agency, Stockholm (Sweden)

1997-10-01

Energy companies, municipalities, property companies, firms of consultants, environmental groups and individuals are examples of players working locally to shape environmentally adapted energy systems. These players have needed information making them better able to make decisions on cost-efficient, environmentally-adapted energy systems. This book answers many of the questions they have put. The volume is mainly based on Swedish handbooks produced by the Swedish National Board for Industrial and Technical Development, NUTEK, together with the Swedish Environmental Protection Agency. These handbooks have been used in conjunction with municipal energy planning, local Agenda 21 work, to provide a basis for deciding on concrete local energy systems. The contents in brief: -The book throws new light on the concept of energy efficiency; -A section on the environment compares how air-polluting emissions vary with different methods of energy production; -A section contains more than 40 ideas for measures which can be profitable, reduce energy consumption and the impact on the environment all at the same time; -The book gives concrete examples of new, alternative and environmentally-adapted local energy systems. More efficient use of energy is included as a possible change of energy system; -The greatest emphasis is laid upon alternative energy systems for heating. It may be heating in a house, block of flats, office building or school; -Finally, there are examples of environmentally-adapted local energy planning.

General Systems Theory and Instructional Design.

Science.gov (United States)

Salisbury, David F.

The use of general systems theory in the field of instructional systems design (ISD) is explored in this paper. Drawing on work by Young, the writings of 12 representative ISD writers and researchers were surveyed to determine the use of 60 general systems theory concepts by the individual authors. The average number of concepts used by these…

Accurate correlation energies in one-dimensional systems from small system-adapted basis functions

Science.gov (United States)

Baker, Thomas E.; Burke, Kieron; White, Steven R.

2018-02-01

We propose a general method for constructing system-dependent basis functions for correlated quantum calculations. Our construction combines features from several traditional approaches: plane waves, localized basis functions, and wavelets. In a one-dimensional mimic of Coulomb systems, it requires only 2-3 basis functions per electron to achieve high accuracy, and reproduces the natural orbitals. We illustrate its effectiveness for molecular energy curves and chains of many one-dimensional atoms. We discuss the promise and challenges for realistic quantum chemical calculations.

Proceedings of the 1. General Congress of Nuclear Energy. v. 2

International Nuclear Information System (INIS)

1986-01-01

The proceedings of I General Congress of Nuclear Energy are presented. All fields related to nuclear energy are enclosed. In the second part the following fields are shown: reactor instrumentation and control, nuclear medicine, radioisotopes uses, fuel cycle and radiation protection. (M.C.K.) [pt

Blockchain-Assisted Crowdsourced Energy Systems

OpenAIRE

Wang, Shen; Taha, Ahmad; Wang, Jianhui

2018-01-01

Crowdsourcing relies on people's contributions to meet product- or system-level objectives. Crowdsourcing-based methods have been implemented in various cyber-physical systems and realtime markets. This paper explores a framework for Crowdsourced Energy Systems (CES), where small-scale energy generation or energy trading is crowdsourced from distributed energy resources, electric vehicles, and shapable loads. The merits/pillars of energy crowdsourcing are discussed. Then, an operational model...

High fidelity nuclear energy system optimization towards an environmentally benign, sustainable, and secure energy source

International Nuclear Information System (INIS)

Tsvetkov, Pavel Valeryevich; Rodriguez, Salvador B.; Ames, David E. II; Rochau, Gary Eugene

2010-01-01

A new high-fidelity integrated system method and analysis approach was developed and implemented for consistent and comprehensive evaluations of advanced fuel cycles leading to minimized Transuranic (TRU) inventories. The method has been implemented in a developed code system integrating capabilities of Monte Carlo N - Particle Extended (MCNPX) for high-fidelity fuel cycle component simulations. In this report, a Nuclear Energy System (NES) configuration was developed to take advantage of used fuel recycling and transmutation capabilities in waste management scenarios leading to minimized TRU waste inventories, long-term activities, and radiotoxicities. The reactor systems and fuel cycle components that make up the NES were selected for their ability to perform in tandem to produce clean, safe, and dependable energy in an environmentally conscious manner. The diversity in performance and spectral characteristics were used to enhance TRU waste elimination while efficiently utilizing uranium resources and providing an abundant energy source. A computational modeling approach was developed for integrating the individual models of the NES. A general approach was utilized allowing for the Integrated System Model (ISM) to be modified in order to provide simulation for other systems with similar attributes. By utilizing this approach, the ISM is capable of performing system evaluations under many different design parameter options. Additionally, the predictive capabilities of the ISM and its computational time efficiency allow for system sensitivity/uncertainty analysis and the implementation of optimization techniques.

High fidelity nuclear energy system optimization towards an environmentally benign, sustainable, and secure energy source.

Energy Technology Data Exchange (ETDEWEB)

Tsvetkov, Pavel Valeryevich (Texas A& M University, College Station, TX); Rodriguez, Salvador B.; Ames, David E., II (Texas A& M University, College Station, TX); Rochau, Gary Eugene

2010-10-01

A new high-fidelity integrated system method and analysis approach was developed and implemented for consistent and comprehensive evaluations of advanced fuel cycles leading to minimized Transuranic (TRU) inventories. The method has been implemented in a developed code system integrating capabilities of Monte Carlo N - Particle Extended (MCNPX) for high-fidelity fuel cycle component simulations. In this report, a Nuclear Energy System (NES) configuration was developed to take advantage of used fuel recycling and transmutation capabilities in waste management scenarios leading to minimized TRU waste inventories, long-term activities, and radiotoxicities. The reactor systems and fuel cycle components that make up the NES were selected for their ability to perform in tandem to produce clean, safe, and dependable energy in an environmentally conscious manner. The diversity in performance and spectral characteristics were used to enhance TRU waste elimination while efficiently utilizing uranium resources and providing an abundant energy source. A computational modeling approach was developed for integrating the individual models of the NES. A general approach was utilized allowing for the Integrated System Model (ISM) to be modified in order to provide simulation for other systems with similar attributes. By utilizing this approach, the ISM is capable of performing system evaluations under many different design parameter options. Additionally, the predictive capabilities of the ISM and its computational time efficiency allow for system sensitivity/uncertainty analysis and the implementation of optimization techniques.

General Systems Theory and Instructional Systems Design.

Science.gov (United States)

Salisbury, David F.

1990-01-01

Describes basic concepts in the field of general systems theory (GST) and identifies commonalities that exist between GST and instructional systems design (ISD). Models and diagrams that depict system elements in ISD are presented, and two matrices that show how GST has been used in ISD literature are included. (11 references) (LRW)

Simulation-based optimization of sustainable national energy systems

International Nuclear Information System (INIS)

Batas Bjelić, Ilija; Rajaković, Nikola

2015-01-01

The goals of the EU2030 energy policy should be achieved cost-effectively by employing the optimal mix of supply and demand side technical measures, including energy efficiency, renewable energy and structural measures. In this paper, the achievement of these goals is modeled by introducing an innovative method of soft-linking of EnergyPLAN with the generic optimization program (GenOpt). This soft-link enables simulation-based optimization, guided with the chosen optimization algorithm, rather than manual adjustments of the decision vectors. In order to obtain EnergyPLAN simulations within the optimization loop of GenOpt, the decision vectors should be chosen and explained in GenOpt for scenarios created in EnergyPLAN. The result of the optimization loop is an optimal national energy master plan (as a case study, energy policy in Serbia was taken), followed with sensitivity analysis of the exogenous assumptions and with focus on the contribution of the smart electricity grid to the achievement of EU2030 goals. It is shown that the increase in the policy-induced total costs of less than 3% is not significant. This general method could be further improved and used worldwide in the optimal planning of sustainable national energy systems. - Highlights: • Innovative method of soft-linking of EnergyPLAN with GenOpt has been introduced. • Optimal national energy master plan has been developed (the case study for Serbia). • Sensitivity analysis on the exogenous world energy and emission price development outlook. • Focus on the contribution of smart energy systems to the EU2030 goals. • Innovative soft-linking methodology could be further improved and used worldwide.

Energy demand and thermal comfort of HVAC systems with thermally activated building systems as a function of user profile

Science.gov (United States)

Pałaszyńska, Katarzyna; Bandurski, Karol; Porowski, Mieczysław

2017-11-01

Thermally Activated Building Systems (TABS) are a way to use building structure as a thermal energy storage. As a result, renewable energy sources may be used more efficiently. The paper presents numerical analysis of a HVAC system with TABS energy demand and indoor thermal comfort of a representative room in a non-residential building (governmental, commercial, educational). The purpose of analysis is to investigate the influence of a user profile on system performance. The time span of the analysis is one year - a typical meteorological year. The model was prepared using a generally accepted simulation tool - TRNSYS 17. The results help to better understand the interaction of a user profile with TABS. Therefore they are important for the development of optimal control algorithms for energy efficient buildings equipped with such systems.

Renewable energy systems a smart energy systems approach to the choice and modeling of 100% renewable solutions

CERN Document Server

Lund, Henrik

2014-01-01

In this new edition of Renewable Energy Systems, globally recognized renewable energy researcher and professor, Henrik Lund, sets forth a straightforward, comprehensive methodology for comparing different energy systems' abilities to integrate fluctuating and intermittent renewable energy sources. The book does this by presenting an energy system analysis methodology and offering a freely available accompanying software tool, EnergyPLAN, which automates and simplifies the calculations supporting such a detailed comparative analysis. The book provides the results of more than fifteen comprehensive energy system analysis studies, examines the large-scale integration of renewable energy into the present system, and presents concrete design examples derived from a dozen renewable energy systems around the globe. Renewable Energy Systems, Second Edition also undertakes the socio-political realities governing the implementation of renewable energy systems by introducing a theoretical framework approach aimed at ...

Optimal unit sizing of a hybrid renewable energy system for isolated applications; Optimalite des elements d'un systeme decentralise de production d'energie electrique

Energy Technology Data Exchange (ETDEWEB)

Morales, D

2006-07-15

In general, the methods used to conceive a renewable energy production system overestimate the size of the generating units. These methods increase the investment cost and the production cost of energy. The work presented in this thesis proposes a methodology to optimally size a renewable energy system.- This study shows that the classic approach based only on a long term analysis of system's behaviour is not sufficient and a complementary methodology based on a short term analysis is proposed. A numerical simulation was developed in which the mathematical models of the solar panel, the wind turbines and battery are integrated. The daily average solar energy per m2 is decomposed into a series of hourly I energy values using the Collares-Pereira equations. The time series analysis of the wind speed is made using the Monte Carlo Simulation Method. The second part of this thesis makes a detailed analysis of an isolated wind energy production system. The average energy produced by the system depends on the generator's rated power, the total swept area of the wind turbine, the gearbox's transformation ratio, the battery voltage and the wind speed probability function. The study proposes a methodology to determine the optimal matching between the rated power of the permanent magnet synchronous machine and the wind turbine's rotor size. This is made taking into account the average electrical energy produced over a period of time. (author)

10 CFR 205.350 - General purpose.

Science.gov (United States)

2010-01-01

... 10 Energy 3 2010-01-01 2010-01-01 false General purpose. 205.350 Section 205.350 Energy DEPARTMENT OF ENERGY OIL ADMINISTRATIVE PROCEDURES AND SANCTIONS Electric Power System Permits and Reports....350 General purpose. The purpose of this rule is to establish a procedure for the Office of...

Annual report 2001. General direction of energy and raw materials; Rapport annuel 2001. Direction generale de l'energie et des matieres premieres

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-07-01

This report summarizes the 2001 activity of the French general direction of energy and raw materials (DGEMP) of the ministry of finances and industry: 1 - security of energy supplies: a recurrent problem; 2001, a transition year for nuclear energy worldwide; petroleum refining in font of the 2005 dead-line; the OPEC and the upset of the oil market; the pluri-annual planning of power production investments; renewable energies: a reconfirmed priority; 2 - the opening of markets: the opening of French electricity and gas markets; the international development of Electricite de France (EdF) and of Gaz de France (GdF); electricity and gas industries: first branch agreements; 3 - the present-day topics: 2001, the year of objective contracts; AREVA, the future to be prepared; the new IRSN; the agreements on climate and the energy policy; the mastery of domestic energy consumptions; the safety of hydroelectric dams; Technip-Coflexip: the birth of a para-petroleum industry giant; the cleansing of the mining activity in French Guyana; the future of workmen of Lorraine basin coal mines; 4 - 2001 at a glance: highlights; main legislative and regulatory texts; 5 - DGEMP: November 2001 reorganization and new organization chart; energy and raw materials publications; www.industrie.gouv.fr/energie. (J.S.)

The fusion-hydrogen energy system

International Nuclear Information System (INIS)

Williams, L.O.

1994-01-01

This paper will describe the structure of the system, from energy generation and hydrogen production through distribution to the end users. It will show how stationary energy users will convert to hydrogen and will outline ancillary uses of hydrogen to aid in reducing other forms of pollution. It will show that the adoption of the fusion hydrogen energy system will facilitate the use of renewable energy such as wind and solar. The development of highly efficient fuel cells for production of electricity near the user and for transportation will be outlined. The safety of the hydrogen fusion energy system is addressed. This paper will show that the combination of fusion generation combined with hydrogen distribution will provide a system capable of virtually eliminating the negative impact on the environment from the use of energy by humanity. In addition, implementation of the energy system will provide techniques and tools that can ameliorate environmental problems unrelated to energy use. (Author)

Generalized stacking fault energies of alloys.

Science.gov (United States)

Li, Wei; Lu, Song; Hu, Qing-Miao; Kwon, Se Kyun; Johansson, Börje; Vitos, Levente

2014-07-02

The generalized stacking fault energy (γ surface) provides fundamental physics for understanding the plastic deformation mechanisms. Using the ab initio exact muffin-tin orbitals method in combination with the coherent potential approximation, we calculate the γ surface for the disordered Cu-Al, Cu-Zn, Cu-Ga, Cu-Ni, Pd-Ag and Pd-Au alloys. Studying the effect of segregation of the solute to the stacking fault planes shows that only the local chemical composition affects the γ surface. The calculated alloying trends are discussed using the electronic band structure of the base and distorted alloys.Based on our γ surface results, we demonstrate that the previous revealed 'universal scaling law' between the intrinsic energy barriers (IEBs) is well obeyed in random solid solutions. This greatly simplifies the calculations of the twinning measure parameters or the critical twinning stress. Adopting two twinnability measure parameters derived from the IEBs, we find that in binary Cu alloys, Al, Zn and Ga increase the twinnability, while Ni decreases it. Aluminum and gallium yield similar effects on the twinnability.

Generalized trends in the formation energies of perovskite oxides.

Science.gov (United States)

Zeng, ZhenHua; Calle-Vallejo, Federico; Mogensen, Mogens B; Rossmeisl, Jan

2013-05-28

Generalized trends in the formation energies of several families of perovskite oxides (ABO3) and plausible explanations to their existence are provided in this study through a combination of DFT calculations, solid-state physics analyses and simple physical/chemical descriptors. The studied elements at the A site of perovskites comprise rare-earth, alkaline-earth and alkaline metals, whereas 3d and 5d metals were studied at the B site. We also include ReO3-type compounds, which have the same crystal structure of cubic ABO3 perovskites except without A-site elements. From the observations we extract the following four conclusions for the perovskites studied in the present paper: for a given cation at the B site, (I) perovskites with cations of identical oxidation state at the A site possess close formation energies; and (II) perovskites with cations of different oxidation states at the A site usually have quite different but ordered formation energies. On the other hand, for a given A-site cation, (III) the formation energies of perovskites vary linearly with respect to the atomic number of the elements at the B site within the same period of the periodic table, and the slopes depend systematically on the oxidation state of the A-site cation; and (IV) the trends in formation energies of perovskites with elements from different periods at the B site depend on the oxidation state of A-site cations. Since the energetics of perovskites is shown to be the superposition of the individual contributions of their constituent oxides, the trends can be rationalized in terms of A-O and B-O interactions in the ionic crystal. These findings reveal the existence of general systematic trends in the formation energies of perovskites and provide further insight into the role of ion-ion interactions in the properties of ternary compounds.

On generalized Volterra systems

Science.gov (United States)

Charalambides, S. A.; Damianou, P. A.; Evripidou, C. A.

2015-01-01

We construct a large family of evidently integrable Hamiltonian systems which are generalizations of the KM system. The algorithm uses the root system of a complex simple Lie algebra. The Hamiltonian vector field is homogeneous cubic but in a number of cases a simple change of variables transforms such a system to a quadratic Lotka-Volterra system. We present in detail all such systems in the cases of A3, A4 and we also give some examples from higher dimensions. We classify all possible Lotka-Volterra systems that arise via this algorithm in the An case.

Decarbonization of Croatian Energy System

International Nuclear Information System (INIS)

Potocnik, V.

2012-01-01

Energy system decarbonization is reduction of greenhouse gases (CO 2 ) emission, chiefly from the fossil fuels (coal, oil, natural gas) combustion. The main objective of an energy system decarbonization is the climate change mitigation, and at the same time development of local industry and employment, better environment and health protection, as well as reduction of the fossil fuels import and foreign debt. Croatia has small fossil fuels reserves and large renewable energy sources (RES) reserves, energy efficiency (ENEF) is relatively low, and energy import, according to the actual Energy strategy 2009, should increase from 50% to 70% until 2020. Croatian energy system participates with about one third in the Croatian foreign trade deficit. The main measures of the Croatian energy system decarbonization should be: increasing ENEF (energy savings), switch from fossil fuels to RES, administrative measures (low carbon development strategy, environmental tax reform, and decoupling income from energy sales). By urgent application of these measures, Croatia could become fossil fuels free until the year 2050.(author)

Some general scaling rules in high energy heavy ion reactions

International Nuclear Information System (INIS)

Andersson, B.; Idh, J.; Otterlund, I.; Stenlund, E.

1988-09-01

We show, using the Fritiof model scenario that the wide variation in the number of participating nucleons tend to drown other dynamical variations in the measurables of high energy ion collisions. We propose a set if general scaling laws for inclusive distributions in which it is the mean multiplicity and the mean transverse energy from each source which are the measurables in the interactions. (authors)

Exploring Reaction Mechanism on Generalized Force Modified Potential Energy Surfaces (G-FMPES) for Diels-Alder Reaction

Science.gov (United States)

Jha, Sanjiv; Brown, Katie; Subramanian, Gopinath

We apply a recent formulation for searching minimum energy reaction path (MERP) and saddle point to atomic systems subjected to an external force. We demonstrate the effect of a loading modality resembling hydrostatic pressure on the trans to cis conformational change of 1,3-butadiene, and the simplest Diels-Alder reaction between ethylene and 1,3-butadiene. The calculated MERP and saddle points on the generalized force modified potential energy surface (G-FMPES) are compared with the corresponding quantities on an unmodified potential energy surface. Our study is performed using electronic structure calculations at the HF/6-31G** level as implemented in the AIMS-MOLPRO code. Our calculations suggest that the added compressive pressure lowers the energy of cis butadiene. The activation energy barrier for the concerted Diels-Alder reaction is found to decrease progressively with increasing compressive pressure.

Modelling of a Hybrid Energy System for Autonomous Application

Directory of Open Access Journals (Sweden)

Yang He

2013-10-01

Full Text Available A hybrid energy system (HES is a trending power supply solution for autonomous devices. With the help of an accurate system model, the HES development will be efficient and oriented. In spite of various precise unit models, a HES system is hardly developed. This paper proposes a system modelling approach, which applies the power flux conservation as the governing equation and adapts and modifies unit models of solar cells, piezoelectric generators, a Li-ion battery and a super-capacitor. A generalized power harvest, storage and management strategy is also suggested to adapt to various application scenarios.

Generalized quantum mean-field systems and their application to ultracold atoms

International Nuclear Information System (INIS)

Trimborn-Witthaut, Friederike Annemarie

2011-01-01

Strongly interacting many-body systems consisting of a large number of indistinguishable particles play an important role in many areas of physics. Though such systems are hard to deal with theoretically since the dimension of the respective Hilbert space increases exponentially both in the particle number and in the number of system modes. Therefore, approximations are of considerable interest. The mean-field approximation describes the behaviour in the macroscopic limit N→∞, which leads to an effective nonlinear single-particle problem. Although this approximation is widely used, rigorous results on the applicability and especially on finite size corrections are extremely rare. One prominent example of strongly interacting many-body systems are ultracold atoms in optical lattices, which are a major subject of this thesis. Typically these systems consist of a large but well-defined number of particles, such that corrections to the mean-field limit can be systematically studied. This thesis is divided into two parts: In the first part we study generalized quantum mean-field systems in a C * -algebraic framework. These systems are characterized by their intrinsic permutation symmetry. In the limit of infinite system size, N→∞, the intensive observables converge to the commutative algebra of weak * -continuous functions on the single particle state space. To quantify the deviations from the meanfield prediction for large but finite N, we establish a differential calculus for state space functions and provide a generalized Taylor expansion around the mean-field limit. Furthermore, we introduce the algebra of macroscopic fluctuations around the mean-field limit and prove a quantum version of the central limit theorem. On the basis of these results, we give a detailed study of the finite size corrections to the ground state energy and establish bounds, for both the quantum and the classical case. Finally, we restrict ourselves to the subspace of Bose

ENERGY AND CONSTRUCTION CONDITIONS OF THE EFFECTIVENESS OF APPAATUS FOR GENERAL CRYOTHERAPEUTIC IMPACT

Directory of Open Access Journals (Sweden)

A. U. Baranov

2016-01-01

Full Text Available Objectives. To evaluate the correspondence of construction and power consumption of Cryotherapeutic Complexes (CTC with technological conditions of effectiveness of the General Cryotherapeutic Impact (GCI. Methods. The associated analysis method used Cryotherapeutic Complexes (CTC construction and power consumption with technological conditions of effectiveness of the General Cryotherapeutic Impact (GCI. Results. An explanation for the discrepancy of observations of different researchers in differences in design and available power of the CTC is proposed. The technical operating characteristics of single-seat and multi-seat CTC are provided and these significant differences in apparatus of identical technological designation are illustrated. The proposed system of specific CTC characteristics is capable of unifying their basic structural and energy characteristics. Calculation of the specific characteristics of existing systems showed that between objects of the same designation, there are differences in value, which may be the cause of discrepancies in their therapeutic efficacy. All functional CPC have a cryostatting cooling capacity system deficit of between 8 and 75%. In multi-seat CPC cooling capacity deficit exceeds 50%, which excludes the possibility of obtaining a significant therapeutic effect, as is confirmed by the results of independent studies that show that the procedures in multi-seat CTC safeguards skin from frigorism only up to 14°C, while at the same time for effective OKV frigorism of the skin surface is necessary to a temperature of less than about 2°C. Prior to research on the effectiveness of OKV, it is necessary to assess the energy consumption conformity of cryotherapy equipment. Conclusion. For the successful implementation of OKV in medicine and sport, it is necessary to increase energy efficiency and optimise cryotherapeutic temperature control settings. A cryotheraputic complex should safeguard such physical

A more general interacting model of holographic dark energy

International Nuclear Information System (INIS)

Yu Fei; Zhang Jingfei; Lu Jianbo; Wang Wei; Gui Yuanxing

2010-01-01

So far, there have been no theories or observational data that deny the presence of interaction between dark energy and dark matter. We extend naturally the holographic dark energy (HDE) model, proposed by Granda and Oliveros, in which the dark energy density includes not only the square of the Hubble scale, but also the time derivative of the Hubble scale to the case with interaction and the analytic forms for the cosmic parameters are obtained under the specific boundary conditions. The various behaviors concerning the cosmic expansion depend on the introduced numerical parameters which are also constrained. The more general interacting model inherits the features of the previous ones of HDE, keeping the consistency of the theory.

The Concept of Autonomous Power Supply System Fed with Renewable Energy Sources

Directory of Open Access Journals (Sweden)

Waldemar Fedak

2017-12-01

Full Text Available Sustainable economic development requires the use of renewable energy sources in a rational and thoughtful way. In Polish conditions the use of several types of renewable energy sources on a single setup is a new issue. In particular, hybrid devices in conjunction with intelligent energy systems, such as lighting systems are generally not used. Therefore, the Polish energy production still relies on the burning of coal. Despite their advantages, renewable energy sources are characterized by seasonality and considerable instability. Access to renewable energy varies daily and seasonally, hence activities promoting the use of autonomous, hybrid power systems must be intensified. The presented research aims at the development of the Autonomous Power Supply (APS system based on the so-called energy mix. Such a system works in an isolated arrangement and serves to reliably supply electricity from renewable sources for small residential or public utility devices in an urban area. Systems with up to 3 kW power consist of modules, whose modular design allows the combination of various power configurations and types of renewable energy used. The basic system consists of a primary power source, additional power source, emergency power source, energy storage device, weather station and controller. The energy mix depends on the geographical location of the system. The emergency source can be implemented as an on-grid connector or fuel power generator with the participation of 100% until the primary or accessory power source failure is removed. The energy storage system consists of batteries or supercapacitors. The proposed system can be combined to create a local network that automatically responds to energy shortages in various network nodes by adjusting the supply of electricity within the network depending on its needs. For Poland realistic solutions in this article are the new and modern answer to these requirements.

Nuclear Energy System Department annual report. (April 1, 2002 - March 31, 2003)

International Nuclear Information System (INIS)

Nakajima, Hajime; Shibata, Keiichi; Kugo, Teruhiko

2003-09-01

This report summarizes the research and development activities in the Department of Nuclear Energy System during the fiscal year of 2002 (April 1, 2002 - March 31, 2003). The Department has carried out researches and developments (R and Ds) of innovative nuclear energy system and their related fundamental technologies to ensure the long-term energy supply in Japan. The report deals with the R and Ds of an innovative water reactor, called Reduced-Moderation Water Reactor (RMWR), which has the capability of multiple recycling and breeding of plutonium using light water reactor technologies. In addition, as basic studies and fundamental researches of nuclear energy system in general, described are intensive researches in the fields of reactor physics, thermal-hydraulics, nuclear data, nuclear fuels, and materials. These activities are essential not only for the R and Ds of innovative nuclear energy systems but also for the improvement of safety and reliability of current nuclear energy systems. The maintenance and operation of reactor engineering facilities belonging to the Department support experimental activities. The activities of the research committees to which the Department takes a role of secretariat are also summarized. (author)

Global energy-momentum conservation in general relativity

International Nuclear Information System (INIS)

Nissani, N.; Leibowitz, E.

1989-01-01

It is shown that there exists a family of coordinate systems in which the energy-momentum tensor is globally conserved. Furthermore, this preferred class of frames includes geodesic systems with respect to any arbitrary point or timelike geodesic line. This implies a physically satisfactory conservation law with no need to introduce an extraneous pseudotensor

Simulation model for wind energy storage systems. Volume I. Technical report. [SIMWEST code

Energy Technology Data Exchange (ETDEWEB)

Warren, A.W.; Edsinger, R.W.; Chan, Y.K.

1977-08-01

The effort developed a comprehensive computer program for the modeling of wind energy/storage systems utilizing any combination of five types of storage (pumped hydro, battery, thermal, flywheel and pneumatic). An acronym for the program is SIMWEST (Simulation Model for Wind Energy Storage). The level of detail of SIMWEST is consistent with a role of evaluating the economic feasibility as well as the general performance of wind energy systems. The software package consists of two basic programs and a library of system, environmental, and load components. Volume I gives a brief overview of the SIMWEST program and describes the two NASA defined simulation studies.

Small Wind Energy Systems

DEFF Research Database (Denmark)

Simões, Marcelo Godoy; Farret, Felix Alberto; Blaabjerg, Frede

2017-01-01

considered when selecting a generator for a wind power plant, including capacity of the AC system, types of loads, availability of spare parts, voltage regulation, technical personal and cost. If several loads are likely inductive, such asphase-controlled converters, motors and fluorescent lights......This chapter intends to serve as a brief guide when someone is considering the use of wind energy for small power applications. It is discussed that small wind energy systems act as the major energy source for residential or commercial applications, or how to make it part of a microgrid...... as a distributed generator. In this way, sources and loads are connected in such a way to behave as a renewable dispatch center. With this regard, non-critical loads might be curtailed or shed during times of energy shortfall or periods of high costs of energy production. If such a wind energy system is connected...

Nonlinear generalization of special relativity at very high energies

International Nuclear Information System (INIS)

Winterberg, F.

1984-01-01

It is shown, that the introduction of a fundamental length constant into the operator representation of the quantum mechanical commutation relations, as suggested by Bagge, leads to a nonlinear generalization of the Lorentz transformations. The theory requires the introduction of a substratum (ether) and which can be identified as the zero point vacuum energy. At very high energies a non-Lorentz invariant behaviour for the cross sections between elementary particles is predicted. Using the Einstein clock synchronisation definition, the velocity of light is also constant and equal to c in the new theory, but the zero point vacuum energy becomes finite, as are all other quantities which are divergent in Lorentz invariant quantum field theories. In the limiting case where the length constant is set equal to zero, the zero point vacuum energy diverges and special relativity is recovered. (orig.) [de

Convergence to Equilibrium in Energy-Reaction-Diffusion Systems Using Vector-Valued Functional Inequalities

Science.gov (United States)

Mielke, Alexander; Mittnenzweig, Markus

2018-04-01

We discuss how the recently developed energy dissipation methods for reaction diffusion systems can be generalized to the non-isothermal case. For this, we use concave entropies in terms of the densities of the species and the internal energy, where the importance is that the equilibrium densities may depend on the internal energy. Using the log-Sobolev estimate and variants for lower-order entropies as well as estimates for the entropy production of the nonlinear reactions, we give two methods to estimate the relative entropy by the total entropy production, namely a somewhat restrictive convexity method, which provides explicit decay rates, and a very general, but weaker compactness method.

Optimal Scheduling of an Regional Integrated Energy System with Energy Storage Systems for Service Regulation

Directory of Open Access Journals (Sweden)

Hengrui Ma

2018-01-01

Full Text Available Ancillary services are critical to maintaining the safe and stable operation of power systems that contain a high penetration level of renewable energy resources. As a high-quality regulation resource, the regional integrated energy system (RIES with energy storage system (ESS can effectively adjust the non-negligible frequency offset caused by the renewable energy integration into the power system, and help solve the problem of power system frequency stability. In this paper, the optimization model aiming at regional integrated energy system as a participant in the regulation market based on pay-for-performance is established. Meanwhile YALMIP + CPLEX is used to simulate and analyze the total operating cost under different dispatch modes. This paper uses the actual operation model of the PJM regulation market to guide the optimal allocation of regulation resource in the regional integrated energy system, and provides a balance between the power trading revenue and regulation market revenue in order to achieve the maximum profit.

Energy Systems Integration Partnerships: NREL + Cogent Energy Systems

Energy Technology Data Exchange (ETDEWEB)

Berdahl, Sonja E [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2017-08-09

NREL is collaborating with Cogent Energy Systems (Cogent) to introduce small-scale waste-to-energy technology in microgrids.The focus of the project is to test and demonstrate the feasibility, reliability, and usefulness of integrating electricity generated using a simulated syngas composition matching the syngas stream to be produced by a HelioStorm-based WTE gasifier to power a microgrid as a means of addressing and complementing the intermittency of other sources of electricity.

Energy demand and thermal comfort of HVAC systems with thermally activated building systems as a function of user profile

Directory of Open Access Journals (Sweden)

Pałaszyńska Katarzyna

2017-01-01

Full Text Available Thermally Activated Building Systems (TABS are a way to use building structure as a thermal energy storage. As a result, renewable energy sources may be used more efficiently. The paper presents numerical analysis of a HVAC system with TABS energy demand and indoor thermal comfort of a representative room in a non-residential building (governmental, commercial, educational. The purpose of analysis is to investigate the influence of a user profile on system performance. The time span of the analysis is one year – a typical meteorological year. The model was prepared using a generally accepted simulation tool – TRNSYS 17. The results help to better understand the interaction of a user profile with TABS. Therefore they are important for the development of optimal control algorithms for energy efficient buildings equipped with such systems.

An enterprise energy-information system

Energy Technology Data Exchange (ETDEWEB)

Swords, B.; Coyle, E. [School of Control Systems and Electrical Engineering, Dublin Institute of Technology, Kevin St., Dublin 8 (Ireland); Norton, B. [President, Dublin Institute of Technology, Aungier St., Dublin 2 (Ireland)

2008-01-15

This paper outlines the background, development, and assessment of a prototype enterprise energy information system (EEIS) that supports strategic energy-management by providing comprehensive energy monitoring and targeting, integrating with energy modelling software and enterprise business databases, and supporting measurement and verification (M and V). The EEIS prototype system was developed and assessed in an industrial site and a third-level education institution with colleges throughout Dublin. The industrial site provided the opportunity for the EEIS to meet the requirements of a large energy intensive site, and to integrate with energy modelling software. The higher education establishment accommodated the development of a networked energy-information system. (author)

Energy-Aware Cognitive Radio Systems

KAUST Repository

Bedeer, Ebrahim

2016-01-15

The concept of energy-aware communications has spurred the interest of the research community in the most recent years due to various environmental and economical reasons. It becomes indispensable for wireless communication systems to shift their resource allocation problems from optimizing traditional metrics, such as throughput and latency, to an environmental-friendly energy metric. Although cognitive radio systems introduce spectrum efficient usage techniques, they employ new complex technologies for spectrum sensing and sharing that consume extra energy to compensate for overhead and feedback costs. Considering an adequate energy efficiency metric—that takes into account the transmit power consumption, circuitry power, and signaling overhead—is of momentous importance such that optimal resource allocations in cognitive radio systems reduce the energy consumption. A literature survey of recent energy-efficient based resource allocations schemes is presented for cognitive radio systems. The energy efficiency performances of these schemes are analyzed and evaluated under power budget, co-channel and adjacent-channel interferences, channel estimation errors, quality-of-service, and/or fairness constraints. Finally, the opportunities and challenges of energy-aware design for cognitive radio systems are discussed.

Prognostication of regional energy system development

Directory of Open Access Journals (Sweden)

Grigoriy Borisovich Korovin

2011-06-01

Full Text Available This paper analyzes practice and development of new methodological approaches to forecasting the development of regional energy systems. It is shown that the energy complex is involved in a variety of forward and backward linkages as an element of socio-economic systems, and the quality and availability of energy resources largely determines the structure and pace of economic, social and environmental development of the region. Analysis of existing current practice of territorial and sectoral forecasting implemented in Russia and abroad, suggests that such practice is inadequate in its theoretical and methodological elaboration. This is confirmed by the frequent discrepancy between actual results and plans, as well as their regular revision. The methods are mostly based on extrapolation of existing tendencies and not taking into account many factors and emerging trends related to the complexity and openness of the social and economic systems. Post-industrial level of civilization is characterized by fast development of technology; knowledge, information, technological and institutional innovation become the main resources. The greatest importance is attached to such development properties as instability, various orderliness, nonlinearity, interactions etc. Current approaches to forecasting the future are described by a number of theories that are generally called self-organization theory, taking into account these singularities. These concepts should be included in the theoretical basis for the development and implementation of regional development forecasts. Using the synergetic approach assumes that, along with organizational processes, processes of self-organization and self-development are very important in the system, they are characterized by spontaneous, unexpected formations and emerging structures. The development of such systems can generate stable and efficient new structure. The presence of crisis is an integral feature of complex

Wind energy analysis system

OpenAIRE

2014-01-01

M.Ing. (Electrical & Electronic Engineering) One of the most important steps to be taken before a site is to be selected for the extraction of wind energy is the analysis of the energy within the wind on that particular site. No wind energy analysis system exists for the measurement and analysis of wind power. This dissertation documents the design and development of a Wind Energy Analysis System (WEAS). Using a micro-controller based design in conjunction with sensors, WEAS measure, calcu...

Dissipative generalized Chaplygin gas as phantom dark energy

International Nuclear Information System (INIS)

Cruz, Norman; Lepe, Samuel; Pena, Francisco

2007-01-01

The generalized Chaplygin gas, characterized by the equation of state p=-A/ρ α , has been considered as a model for dark energy due to its dark-energy-like evolution at late times. When dissipative processes are taken into account, within the framework of the standard Eckart theory of relativistic irreversible thermodynamics, cosmological analytical solutions are found. Using the truncated causal version of the Israel-Stewart formalism, a suitable model was constructed which crosses the w=-1 barrier. The future-singularities encountered in both approaches are of a new type, and not included in the classification presented by Nojiri and Odintsov [S. Nojiri, S.D. Odintsov, Phys. Rev. D 72 (2005) 023003

Dissipative generalized Chaplygin gas as phantom dark energy

Energy Technology Data Exchange (ETDEWEB)

Cruz, Norman [Departamento de Fisica, Facultad de Ciencia, Universidad de Santiago, Casilla 307, Santiago (Chile)]. E-mail: ncruz@lauca.usach.cl; Lepe, Samuel [Instituto de Fisica, Facultad de Ciencias Basicas y Matematicas, Pontificia Universidad Catolica de Valparaiso, Avenida Brasil 2950, Valparaiso (Chile)]. E-mail: slepe@ucv.cl; Pena, Francisco [Departamento de Ciencias Fisicas, Facultad de Ingenieria, Ciencias y Administracion, Universidad de la Frontera, Avda. Francisco Salazar 01145, Casilla 54-D, Temuco (Chile)]. E-mail: fcampos@ufro.cl

2007-03-15

The generalized Chaplygin gas, characterized by the equation of state p=-A/{rho}{sup {alpha}}, has been considered as a model for dark energy due to its dark-energy-like evolution at late times. When dissipative processes are taken into account, within the framework of the standard Eckart theory of relativistic irreversible thermodynamics, cosmological analytical solutions are found. Using the truncated causal version of the Israel-Stewart formalism, a suitable model was constructed which crosses the w=-1 barrier. The future-singularities encountered in both approaches are of a new type, and not included in the classification presented by Nojiri and Odintsov [S. Nojiri, S.D. Odintsov, Phys. Rev. D 72 (2005) 023003].

Energy system analysis of 100% renewable energy systems-The case of Denmark in years 2030 and 2050

DEFF Research Database (Denmark)

Lund, Henrik; Mathiesen, Brian Vad

2009-01-01

for two energy target years: year 2050 with 100% renewable energy from biomass and combinations of wind, wave and solar power; and year 2030 with 50% renewable energy, emphasising the first important steps on the way. The conclusion is that a 100% renewable energy supply based on domestic resources......This paper presents the methodology and results of the overall energy system analysis of a 100% renewable energy system. The input for the systems is the result of a project of the Danish Association of Engineers, in which 1600 participants during more than 40 seminars discussed and designed...... a model for the future energy system of Denmark. The energy system analysis methodology includes hour by hour computer simulations leading to the design of flexible energy systems with the ability to balance the electricity supply and demand. The results are detailed system designs and energy balances...

Analysis of economic characteristics of a tariff system for thermal energy activities

Energy Technology Data Exchange (ETDEWEB)

Banovac, Eraldo [Croatian Energy Regulatory Agency, Zagreb (Croatia); Gelo, Tomislav; Simurina, Jurica [University of Zagreb (Croatia). Faculty of Economics and Business

2007-11-15

Generally speaking, the creation of tariff systems for energy activities carried out as regulated or public service obligation is becoming professionally challenging. The Croatian Energy Regulatory Agency (CERA) created the methodology of the tariff system for thermal energy activities and passed this tariff system (without tariff element amounts) in May 2006. The background of the tariff system for thermal energy activities (heat generation, heat distribution and heat supply) including a legislative framework relevant for passing the tariff system, terminology, matrix of the tariff models, tariff elements and amounts of tariff entries are analyzed in this paper. Special attention is paid to the economic characteristics of the tariff system, such as the capital asset pricing model (CAPM), which is chosen among several models of the weighted average of cost of capital (WACC). Using the WACC, the regulatory authorities ensure returns to be equal to the opportunity cost of capital. Furthermore, main formulae and procedures for submitting the proposal for changing the amounts of tariff elements are analyzed as well. (author)

Analysis of economic characteristics of a tariff system for thermal energy activities

International Nuclear Information System (INIS)

Banovac, Eraldo; Gelo, Tomislav; Simurina, Jurica

2007-01-01

Generally speaking, the creation of tariff systems for energy activities carried out as regulated or public service obligation is becoming professionally challenging. The Croatian Energy Regulatory Agency (CERA) created the methodology of the tariff system for thermal energy activities and passed this tariff system (without tariff element amounts) in May 2006. The background of the tariff system for thermal energy activities (heat generation, heat distribution and heat supply) including a legislative framework relevant for passing the tariff system, terminology, matrix of the tariff models, tariff elements and amounts of tariff entries are analyzed in this paper. Special attention is paid to the economic characteristics of the tariff system, such as the capital asset pricing model (CAPM), which is chosen among several models of the weighted average of cost of capital (WACC). Using the WACC, the regulatory authorities ensure returns to be equal to the opportunity cost of capital. Furthermore, main formulae and procedures for submitting the proposal for changing the amounts of tariff elements are analyzed as well

Self-consistent nuclear energy systems

International Nuclear Information System (INIS)

Shimizu, A.; Fujiie, Y.

1995-01-01

A concept of self-consistent energy systems (SCNES) has been proposed as an ultimate goal of the nuclear energy system in the coming centuries. SCNES should realize a stable and unlimited energy supply without endangering the human race and the global environment. It is defined as a system that realizes at least the following four objectives simultaneously: (a) energy generation -attain high efficiency in the utilization of fission energy; (b) fuel production - secure inexhaustible energy source: breeding of fissile material with the breeding ratio greater than one and complete burning of transuranium through recycling; (c) burning of radionuclides - zero release of radionuclides from the system: complete burning of transuranium and elimination of radioactive fission products by neutron capture reactions through recycling; (d) system safety - achieve system safety both for the public and experts: eliminate criticality-related safety issues by using natural laws and simple logic. This paper describes the concept of SCNES and discusses the feasibility of the system. Both ''neutron balance'' and ''energbalance'' of the system are introduced as the necessary conditions to be satisfied at least by SCNES. Evaluations made so far indicate that both the neutron balance and the energy balance can be realized by fast reactors but not by thermal reactors. Concerning the system safety, two safety concepts: ''self controllability'' and ''self-terminability'' are introduced to eliminate the criticality-related safety issues in fast reactors. (author)

Possible site-specific reagent for the general amino acid transport system of Saccharomyces cerevisiae.

Science.gov (United States)

Larimore, F S; Roon, R J

1978-02-07

The general amino acid transport system of Saccharomyces cerevisiae functions in the uptake of neutral, basic, and acidic amino acids. The amino acid analogue N-delta-chloroacetyl-L-ornithine (NCAO) has been tested as potential site specific reagent for this system. L-Tryptophan, which is transported exclusively by the general transport system, was used as a substrate. In the presence of glucose as an energy source, NCAO inhibited tryptophan transport competitively (Ki = 80 micrometer) during short time intervals (1-2 min), but adding 100 micrometer NCAO to a yeast cell suspension resulted in a time-dependent activation of tryptophan transport during the first 15 min of treatment. Following the activation a time-dependent decay of tryptophan transport activity occurred. Approximately 80% inactivation of the system was observed after 90 min. When a yeast cell suspension was treated with NCAO in the absence of an energy source, an 80% inactivation of tryptophan transport occurred in 90 min. The inactivation was noncompetitive (Ki congruent to 60 micrometer) and could not be reversed by the removal of the NCAO. Addition of a five-fold excess of L-lysine during NCAO treatment or prevented inactivation of tryptophan transport. Under parallel conditions of incubation, other closely related transport systems were not inhibited by NCAO.

Living Systems Energy Module

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-09-26

The Living Systems Energy Module, renamed Voyage from the Sun, is a twenty-lesson curriculum designed to introduce students to the major ways in which energy is important in living systems. Voyage from the Sun tells the story of energy, describing its solar origins, how it is incorporated into living terrestrial systems through photosynthesis, how it flows from plants to herbivorous animals, and from herbivores to carnivores. A significant part of the unit is devoted to examining how humans use energy, and how human impact on natural habitats affects ecosystems. As students proceed through the unit, they read chapters of Voyage from the Sun, a comic book that describes the flow of energy in story form (Appendix A). During the course of the unit, an ``Energy Pyramid`` is erected in the classroom. This three-dimensional structure serves as a classroom exhibit, reminding students daily of the importance of energy and of the fragile nature of our living planet. Interactive activities teach students about adaptations that allow plants and animals to acquire, to use and to conserve energy. A complete list of curricular materials and copies of all activity sheets appear in Appendix B.

Effects of Low Anisotropy on Generalized Ghost Dark Energy in Galileon Gravity

Science.gov (United States)

Hossienkhani, H.; Fayaz, V.; Jafari, A.; Yousefi, H.

2018-04-01

The definition of the Galileon gravity form is extended to the Brans-Dicke theory. Given, the framework of the Galileon theory, the generalized ghost dark energy model in an anisotropic universe is investigated. We study the cosmological implications of this model. In particular, we obtain the equation of state and the deceleration parameters and a differential equation governing the evolution of this dark energy in Bianchi type I model. We also probe observational constraints by using the latest observational data on the generalized ghost dark energy models as the unification of dark matter and dark energy. In order to do so, we focus on observational determinations of the Hubble expansion rate (namely, the expansion history) H(z). As a result, we show the influence of the anisotropy (although low) on the evolution of the universe in the statefinder diagrams for Galileon gravity.

Thermal energy systems design and analysis

CERN Document Server

Penoncello, Steven G

2015-01-01

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

Energy systems transformation.

Science.gov (United States)

Dangerman, A T C Jérôme; Schellnhuber, Hans Joachim

2013-02-12

The contemporary industrial metabolism is not sustainable. Critical problems arise at both the input and the output side of the complex: Although affordable fossil fuels and mineral resources are declining, the waste products of the current production and consumption schemes (especially CO(2) emissions, particulate air pollution, and radioactive residua) cause increasing environmental and social costs. Most challenges are associated with the incumbent energy economy that is unlikely to subsist. However, the crucial question is whether a swift transition to its sustainable alternative, based on renewable sources, can be achieved. The answer requires a deep analysis of the structural conditions responsible for the rigidity of the fossil-nuclear energy system. We argue that the resilience of the fossil-nuclear energy system results mainly from a dynamic lock-in pattern known in operations research as the "Success to the Successful" mode. The present way of generating, distributing, and consuming energy--the largest business on Earth--expands through a combination of factors such as the longevity of pertinent infrastructure, the information technology revolution, the growth of the global population, and even the recent financial crises: Renewable-energy industries evidently suffer more than the conventional-energy industries under recession conditions. Our study tries to elucidate the archetypical traits of the lock-in pattern and to assess the respective importance of the factors involved. In particular, we identify modern corporate law as a crucial system element that thus far has been largely ignored. Our analysis indicates that the rigidity of the existing energy economy would be reduced considerably by the assignment of unlimited liabilities to the shareholders.

A gradient structure for reaction–diffusion systems and for energy-drift-diffusion systems

International Nuclear Information System (INIS)

Mielke, Alexander

2011-01-01

In recent years the theory of the Wasserstein metric has opened up new treatments of diffusion equations as gradient systems, where the free energy or entropy take the role of the driving functional and where the space is equipped with the Wasserstein metric. We show on the formal level that this gradient structure can be generalized to reaction–diffusion systems with reversible mass-action kinetic. The metric is constructed using the dual dissipation potential, which is a quadratic functional of all chemical potentials including the mobilities as well as the reaction kinetics. The metric structure is obtained by Legendre transform from the dual dissipation potential. The same ideas extend to systems including electrostatic interactions or a correct energy balance via coupling to the heat equation. We show this by treating the semiconductor equations involving the electron and hole densities, the electrostatic potential, and the temperature. Thus, the models in Albinus et al (2002 Nonlinearity 15 367–83), which stimulated this work, have a gradient structure

Summary Report of the INL-JISEA Workshop on Nuclear Hybrud Energy Systems

Energy Technology Data Exchange (ETDEWEB)

Mark Antkowiak; Richard Boardman; Shannon Bragg-Sitton; Robert Cherry; Mark Ruth

2012-07-01

Hybrid energy systems utilize two or more energy resources as inputs to two or more physically coupled subsystems to produce one or more energy commodities as outputs. Nuclear hybrid energy systems can be used to provide load-following electrical power to match diurnal to seasonal-scale changes in power demand or to compensate for the variability of renewable wind or solar generation. To maintain economical, full rate operation of the nuclear reactor, its thermal energy available when power demand is low could be diverted into making synthetic vehicle fuels of various types. The Institute for Nuclear Energy Science and Technology (INEST) and the Joint Institute for Strategic Energy Analysis (JISEA) co-sponsored an international workshop to identify research topics important in advancing the potential use of hybrid systems with a specific focus on nuclear-renewable hybrid systems. The workshop included presentations ranging from energy challenges and research and development (R&D) directions being pursued by nations to multiple options for hybrid systems. Those options include one that is being commercialized to other opportunities and analysis results quantifying them. The workshop also involved two breakout sessions - one focused on thermal energy management issues especially at unit-operation scale and the second focused on system operations issues including system controls, regulatory issues, technical and economic analysis, and market challenges. A discussion involving the full group focused on more general issues such as societal involvement and participation. Key criteria for selecting hybrid energy system projects and metrics for comparing them were also identified by the full group. The workshop's findings are being used initially by INEST to define topics for a research preproposal solicitation.

Institutional applications of solar total-energy systems. Draft final report. Volume 2. Appendixes

Energy Technology Data Exchange (ETDEWEB)

None

1978-07-01

The appendices present the analytical basis for the analysis of solar total energy (STE) systems. A regional-climate model and a building-load requirements model are developed, along with fuel-price scenarios. Life-cycle costs are compared for conventional-utility, total energy, and STE systems. Thermal STE system design trade-offs are performed and thermal STE system performance is determined. The sensitivity of STE competitiveness to fuel prices is examined. The selection of the photovoltaic array is briefly discussed. The institutional-sector decision processes are analyzed. Hypothetical regional back-up rates and electrical-energy costs are calculated. The algorithms and equations used in operating the market model are given, and a general methodology is developed for projecting the size of the market for STE systems and applied to each of 8 institutional subsectors. (LEW)

Enthalpy restoration in geothermal energy processing system

Science.gov (United States)

Matthews, Hugh B.

1983-01-01

A geothermal deep well energy extraction system is provided of the general type in which solute-bearing hot water is pumped to the earth's surface from a relatively low temperature geothermal source by transferring thermal energy from the hot water to a working fluid for driving a primary turbine-motor and a primary electrical generator at the earth's surface. The superheated expanded exhaust from the primary turbine motor is conducted to a bubble tank where it bubbles through a layer of sub-cooled working fluid that has been condensed. The superheat and latent heat from the expanded exhaust of the turbine transfers thermal energy to the sub-cooled condensate. The desuperheated exhaust is then conducted to the condenser where it is condensed and sub-cooled, whereupon it is conducted back to the bubble tank via a barometric storage tank. The novel condensing process of this invention makes it possible to exploit geothermal sources which might otherwise be non-exploitable.

Gestalt Therapy and General System Theory.

Science.gov (United States)

Whitner, Phillip A.

While General Systems Theory (GST) concepts appear to be applicable in explaining some of the phenomena that occur in a Gestalt Therapy group, research is needed to support this assumption. General Systems Theory may not be a group theory per se. Instead, GST may be a theory about groups. A meta-theory exists where its value and usefulness is…

Annual report 2001. General direction of energy and raw materials; Rapport annuel 2001. Direction generale de l'energie et des matieres premieres

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-07-01

This report summarizes the 2001 activity of the French general direction of energy and raw materials (DGEMP) of the ministry of finances and industry: 1 - security of energy supplies: a recurrent problem; 2001, a transition year for nuclear energy worldwide; petroleum refining in font of the 2005 dead-line; the OPEC and the upset of the oil market; the pluri-annual planning of power production investments; renewable energies: a reconfirmed priority; 2 - the opening of markets: the opening of French electricity and gas markets; the international development of Electricite de France (EdF) and of Gaz de France (GdF); electricity and gas industries: first branch agreements; 3 - the present-day topics: 2001, the year of objective contracts; AREVA, the future to be prepared; the new IRSN; the agreements on climate and the energy policy; the mastery of domestic energy consumptions; the safety of hydroelectric dams; Technip-Coflexip: the birth of a para-petroleum industry giant; the cleansing of the mining activity in French Guyana; the future of workmen of Lorraine basin coal mines; 4 - 2001 at a glance: highlights; main legislative and regulatory texts; 5 - DGEMP: November 2001 reorganization and new organization chart; energy and raw materials publications; www.industrie.gouv.fr/energie. (J.S.)

Integrated energy optimization with smart home energy management systems

NARCIS (Netherlands)

Asare-Bediako, B.; Ribeiro, P.F.; Kling, W.L.

2012-01-01

Optimization of energy use is a vital concept in providing solutions to many of the energy challenges in our world today. Large chemical, mechanical, pneumatic, hydraulic, and electrical systems require energy efficiency as one of the important aspects of operating systems. At the micro-scale, the

Information-theoretic characterization of dynamic energy systems

Science.gov (United States)

Bevis, Troy Lawson

The latter half of the 20th century saw tremendous growth in nearly every aspect of civilization. From the internet to transportation, the various infrastructures relied upon by society has become exponentially more complex. Energy systems are no exception, and today the power grid is one of the largest infrastructures in the history of the world. The growing infrastructure has led to an increase in not only the amount of energy produced, but also an increase in the expectations of the energy systems themselves. The need for a power grid that is reliable, secure, and efficient is apparent, and there have been several initiatives to provide such a system. These increases in expectations have led to a growth in the renewable energy sources that are being integrated into the grid, a change that increases efficiency and disperses the generation throughout the system. Although this change in the grid infrastructure is beneficial, it leads to grand challenges in system level control and operation. As the number of sources increases and becomes geographically distributed, the control systems are no longer local to the system. This means that communication networks must be enhanced to support multiple devices that must communicate reliably. A common solution to these new systems is to use wide area networks for the communication network, as opposed to point-to-point communication. Although the wide area network will support a large number of devices, it generally comes with a compromise in the form of latency in the communication system. Now the device controller has latency injected into the feedback loop of the system. Also, renewable energy sources are largely non-dispatchable generation. That is, they are never guaranteed to be online and supplying the demanded energy. As renewable generation is typically modeled as stochastic process, it would useful to include this behavior in the control system algorithms. The combination of communication latency and stochastic

Hydrogen based energy storage for solar energy systems

Energy Technology Data Exchange (ETDEWEB)

Vanhanen, J.; Hagstroem, M.; Lund, P. [Helsinki Univ. of Technology, Otaniemi (Finland). Advanced Energy Systems

1998-10-01

The main technical constraint in solar energy systems which operate around the year is the lack of suitable long-term energy storage. Conventional solutions to overcome the problem of seasonal storage in PV power systems are to use oversized batteries as a seasonal energy storage, or to use a diesel back-up generator. However, affordable lead-acid batteries are not very suitable for seasonal energy storage because of a high self-discharge rate and enhanced deterioration and divergence of the single cells during prolonged periods of low state of charge in times of low irradiation. These disadvantages can be avoided by a back-up system, e.g. a diesel generator, which car supply energy to the loads and charge the battery to the full state of charge to avoid the above mentioned disadvantages. Unfortunately, diesel generators have several disadvantages, e.g. poor starting reliability, frequent need for maintenance and noise

Proposal and assessment of a novel integrated CCHP system with biogas steam reforming using solar energy

International Nuclear Information System (INIS)

Su, Bosheng; Han, Wei; Jin, Hongguang

2017-01-01

Highlights: •A novel CCHP system with biogas steam reforming using solar energy is raised. •Chemical and physical energy of biogas is efficiently used in a cascaded way. •The energy quality of concentrating solar heat is promoted in the system. •A parametric analysis is adopted to optimize the thermodynamic performance. •A typical-day study is conducted to explore the general operation features. -- Abstract: The conventional way to utilize biogas either is energy-intensive due to biogas upgrading or causes huge waste of energy grade and environmental pollution by direct burning. This paper proposes a biogas and solar energy-assisted combined cooling, heating and power (BSCCHP) system that upgrades the caloric value of biogas before combustion by introducing a thermochemical conversion process that is driven by solar heat. Adopting commercially established technologies including steam reforming and parabolic dish concentrators, the system exhibits an enhanced system exergy efficiency, and the technology considerably reduces the direct CO 2 footprint and saves depletable fossil fuel. With a solar thermal share of 22.2%, the proposed system not only has a high net solar-to-product thermal and exergy efficiency of 46.80% and 26.49%, respectively, but also results in a commensurate 18.27% reduction of the direct CO 2 footprint compared with the reference individual systems. The effect of critical parameters in the biogas steam reforming process on the system performance was studied. A proper selection of the steam/carbon ratio leads to the optimal direct CO 2 footprint and system exergy efficiency. Pursuing a very high conversion of biogas by improving the reforming temperature is not a wise choice from a system perspective. Finally, a typical-day dynamic simulation was conducted to preliminarily explore the general operation features. This study may provide a new way to efficiently use the renewable energy in the distributed energy system.

Energy storage systems cost update : a study for the DOE Energy Storage Systems Program.

Energy Technology Data Exchange (ETDEWEB)

Schoenung, Susan M. (Longitude 122 West, Menlo Park, CA)

2011-04-01

This paper reports the methodology for calculating present worth of system and operating costs for a number of energy storage technologies for representative electric utility applications. The values are an update from earlier reports, categorized by application use parameters. This work presents an update of energy storage system costs assessed previously and separately by the U.S. Department of Energy (DOE) Energy Storage Systems Program. The primary objective of the series of studies has been to express electricity storage benefits and costs using consistent assumptions, so that helpful benefit/cost comparisons can be made. Costs of energy storage systems depend not only on the type of technology, but also on the planned operation and especially the hours of storage needed. Calculating the present worth of life-cycle costs makes it possible to compare benefit values estimated on the same basis.

Total energy system in the future

International Nuclear Information System (INIS)

Hijikata, K.

1994-01-01

The possibility of improving the thermal efficiency of energy systems from an exergy point of view is discussed. In total energy systems, we should employ multi-pass recycling consisting of thermal and chemical energies. The recycling system is supported by electrical energy, which is provided by a renewable energy source or by excess commercial electric power. This total energy system should be considered not only in one country, but all around the globe. (author). 6 figs., 4 tabs., 8 refs

Thermal Distribution System | Energy Systems Integration Facility | NREL

Science.gov (United States)

Thermal Distribution System Thermal Distribution System The Energy Systems Integration Facility's . Photo of the roof of the Energy Systems Integration Facility. The thermal distribution bus allows low as 10% of its full load level). The 60-ton chiller cools water with continuous thermal control

An enviro-economic function for assessing energy resources for district energy systems

International Nuclear Information System (INIS)

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

2014-01-01

District energy (DE) systems provide an important means of mitigating greenhouse gas emissions and the significant related concerns associated with global climate change. DE systems can use fossil fuels, renewable energy and waste heat as energy sources, and facilitate intelligent integration of energy systems. In this study, an enviro-economic function is developed for assessing various energy sources for a district energy system. The DE system is assessed for the considered energy resources by considering two main factors: CO 2 emissions and economics. Using renewable energy resources and associated technologies as the energy suppliers for a DE system yields environmental benefits which can lead to financial advantages through such instruments as tax breaks; while fossil fuels are increasingly penalized by a carbon tax. Considering these factors as well as the financial value of the technology, an analysis approach is developed for energy suppliers of the DE system. In addition, the proposed approach is modified for the case when thermal energy storage is integrated into a DE system. - Highlights: • Developed a function to assess various energy sources for a district energy system. • Considered CO 2 emissions and economics as two main factors. • Applied renewable energy resources technologies as the suppliers for a DE system. • Yields environmental benefits can lead to financial benefits by tax breaks. • Modified enviro-economic function for the TES integrated into a DE system

Integrated energy systems and local energy markets

DEFF Research Database (Denmark)

Lund, Henrik; Münster, Ebbe

2006-01-01

Significant benefits are connected with an increase in the flexibility of the Danish energy system. On the one hand, it is possible to benefit from trading electricity with neighbouring countries, and on the other, Denmark will be able to make better use of wind power and other types of renewable...... energy in the future. This paper presents the analysis of different ways of increasing flexibility in the Danish energy system by the use of local regulation mechanisms. This strategy is compared with the opposite extreme, i.e. trying to solve all balancing problems via electricity trade...

Heat pipe based cold energy storage systems for datacenter energy conservation

International Nuclear Information System (INIS)

Singh, Randeep; Mochizuki, Masataka; Mashiko, Koichi; Nguyen, Thang

2011-01-01

In the present paper, design and economics of the novel type of thermal control system for datacenter using heat pipe based cold energy storage has been proposed and discussed. Two types of cold energy storage system namely: ice storage system and cold water storage system are explained and sized for datacenter with heat output capacity of 8800 kW. Basically, the cold energy storage will help to reduce the chiller running time that will save electricity related cost and decrease greenhouse gas emissions resulting from the electricity generation from non-renewable sources. The proposed cold energy storage system can be retrofit or connected in the existing datacenter facilities without major design changes. Out of the two proposed systems, ice based cold energy storage system is mainly recommended for datacenters which are located in very cold locations and therefore can offer long term seasonal storage of cold energy within reasonable cost. One of the potential application domains for ice based cold energy storage system using heat pipes is the emergency backup system for datacenter. Water based cold energy storage system provides more compact size with short term storage (hours to days) and is potential for datacenters located in areas with yearly average temperature below the permissible cooling water temperature (∼25 o C). The aforesaid cold energy storage systems were sized on the basis of metrological conditions in Poughkeepsie, New York. As an outcome of the thermal and cost analysis, water based cold energy storage system with cooling capability to handle 60% of datacenter yearly heat load will provide an optimum system size with minimum payback period of 3.5 years. Water based cold energy storage system using heat pipes can be essentially used as precooler for chiller. Preliminary results obtained from the experimental system to test the capability of heat pipe based cold energy storage system have provided satisfactory outcomes and validated the proposed

Energy Storage System with Voltage Equalization Strategy for Wind Energy Conversion

Directory of Open Access Journals (Sweden)

Cheng-Tao Tsai

2012-07-01

Full Text Available In this paper, an energy storage system with voltage equalization strategy for wind energy conversion is presented. The proposed energy storage system provides a voltage equalization strategy for series-connected lead-acid batteries to increase their total storage capacity and lifecycle. In order to draw the maximum power from the wind energy, a perturbation-and-observation method and digital signal processor (DSP are incorporated to implement maximum power point tracking (MPPT algorithm and power regulating scheme. In the proposed energy storage system, all power switches have zero-voltage-switching (ZVS feature at turn-on transition. Therefore, the conversion efficiency can be increased. Finally, a prototype energy storage system for wind energy conversion is built and implemented. Experimental results have verified the performance and feasibility of the proposed energy storage system for wind energy conversion.

Integrated modelling of ecosystem services and energy systems research

Science.gov (United States)

Agarwala, Matthew; Lovett, Andrew; Bateman, Ian; Day, Brett; Agnolucci, Paolo; Ziv, Guy

2016-04-01

The UK Government is formally committed to reducing carbon emissions and protecting and improving natural capital and the environment. However, actually delivering on these objectives requires an integrated approach to addressing two parallel challenges: de-carbonising future energy system pathways; and safeguarding natural capital to ensure the continued flow of ecosystem services. Although both emphasise benefiting from natural resources, efforts to connect natural capital and energy systems research have been limited, meaning opportunities to improve management of natural resources and meet society's energy needs could be missed. The ecosystem services paradigm provides a consistent conceptual framework that applies in multiple disciplines across the natural and economic sciences, and facilitates collaboration between them. At the forefront of the field, integrated ecosystem service - economy models have guided public- and private-sector decision making at all levels. Models vary in sophistication from simple spreadsheet tools to complex software packages integrating biophysical, GIS and economic models and draw upon many fields, including ecology, hydrology, geography, systems theory, economics and the social sciences. They also differ in their ability to value changes in natural capital and ecosystem services at various spatial and temporal scales. Despite these differences, current models share a common feature: their treatment of energy systems is superficial at best. In contrast, energy systems research has no widely adopted, unifying conceptual framework that organises thinking about key system components and interactions. Instead, the literature is organised around modelling approaches, including life cycle analyses, econometric investigations, linear programming and computable general equilibrium models. However, some consistencies do emerge. First, often contain a linear set of steps, from exploration to resource supply, fuel processing, conversion

The heterogeneous gas with singular interaction: generalized circular law and heterogeneous renormalized energy

International Nuclear Information System (INIS)

Molino, Luis Carlos García del; Pakdaman, Khashayar; Touboul, Jonathan

2015-01-01

We introduce and analyze d-dimensional Coulomb gases with random charge distribution and general external confining potential. We show that these gases satisfy a large-deviation principle. The analysis of the minima of the rate function (which is the leading term of the energy) reveals that, at equilibrium, the particle distribution is a generalized circular law (i.e. with spherical support but not necessarily uniform distribution). In the classical electrostatic external potential, there are infinitely many minimizers of the rate function. The most likely macroscopic configuration is a disordered distribution in which particles are uniformly distributed (for d = 2, the circular law), and charges are independent of the positions of the particles. General charge-dependent confining potentials unfold this degenerate situation: in contrast, the particle density is not uniform, and particles spontaneously organize according to their charge. In this picture the classical electrostatic potential appears as a transition at which order is lost. Sub-leading terms of the energy are derived: we show that these are related to an operator, generalizing the Coulomb renormalized energy, which incorporates the heterogeneous nature of the charges. This heterogeneous renormalized energy informs us about the microscopic arrangements of the particles, which are non-standard, strongly dependent on the charges, and include progressive and irregular lattices. (paper)

Refrigeration Playbook: Natural Refrigerants; Selecting and Designing Energy-Efficient Commercial Refrigeration Systems That Use Low Global Warming Potential Refrigerants

Energy Technology Data Exchange (ETDEWEB)

Nelson, Caleb [CTA Architects Engineers, Boise, ID (United States); Reis, Chuck [CTA Architects Engineers, Boise, ID (United States); Nelson, Eric [CTA Architects Engineers, Boise, ID (United States); Armer, James [CTA Architects Engineers, Boise, ID (United States); Arthur, Rob [CTA Architects Engineers, Boise, ID (United States); Heath, Richard [CTA Architects Engineers, Boise, ID (United States); Rono, James [CTA Architects Engineers, Boise, ID (United States); Hirsch, Adam [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Doebber, Ian [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2015-03-01

This report provides guidance for selecting and designing energy efficient commercial refrigeration systems using low global warming potential refrigerants. Refrigeration systems are generally the largest energy end use in a supermarket type building, often accounting for more than half of a building's energy consumption.

Holographic Dark Energy with Generalized Chaplygin Gas in Higher Dimensions

Science.gov (United States)

Ghose, S.; Saha, A.; Paul, B. C.

2014-11-01

We investigate holographic dark energy (HDE) correspondence of interacting Generalized Chaplygin Gas (GCG) in the framework of compact Kaluza-Klein (KK) cosmology. The evolution of the modified HDE with corresponding equation of state is obtained here. Considering the present value of the density parameter a stable configuration is found which accommodates Dark Energy (DE). We note a connection between DE and Phantom fields. It reveals that the DE might have evolved from a Phantom state in the past.

General N-Dark Soliton Solutions of the Multi-Component Mel'nikov System

Science.gov (United States)

Han, Zhong; Chen, Yong; Chen, Junchao

2017-07-01

A general form of N-dark soliton solutions of the multi-component Mel'nikov system are presented. Taking the coupled Mel'nikov system comprised of two-component short waves and one-component long wave as an example, its general N-dark-dark soliton solutions in Gram determinant form are constructed through the KP hierarchy reduction method. The dynamics of single dark-dark soliton and two dark-dark solitons are discussed in detail. It can be shown that the collisions of dark-dark solitons are elastic and energies of the solitons in different components completely transmit through. In addition, the dark-dark soliton bound states including both stationary and moving cases are also investigated. An interesting feature for the coupled Mel'nikov system is that the stationary dark-dark soliton bound states can exist for all possible combinations of nonlinearity coefficients including positive, negative and mixed types, while the moving case are possible when nonlinearity coefficients take opposite signs or they are both negative.

Comparative Study of Electric Energy Storages and Thermal Energy Auxiliaries for Improving Wind Power Integration in the Cogeneration System

Directory of Open Access Journals (Sweden)

Yanjuan Yu

2018-01-01

Full Text Available In regards to the cogeneration system in Northern China, mainly supported by combined heat and power (CHP plants, it usually offers limited operation flexibility due to the joint production of electric and thermal power. For that large-scale wind farms included in the cogeneration system, a large amount of wind energy may have to be wasted. To solve this issue, the utilization of the electric energy storages and the thermal energy auxiliaries are recommended, including pumped hydro storage (PHS, compressed air energy storage (CAES, hydrogen-based energy storage (HES, heat storage (HS, electric boilers (EB, and heat pumps (HP. This paper proposes a general evaluation method to compare the performance of these six different approaches for promoting wind power integration. In consideration of saving coal consumption, reducing CO2 emissions, and increasing investment cost, the comprehensive benefit is defined as the evaluation index. Specifically, a wind-thermal conflicting expression (WTCE is put forward to simplify the formulation of the comprehensive benefit. Further, according to the cogeneration system of the West Inner Mongolia (WIM power grid, a test system is modelled to perform the comparison of the six different approaches. The results show that introducing the electric energy storages and the thermal energy auxiliaries can both contribute to facilitating wind power integration, and the HP can provide the best comprehensive benefit.

HTGR molten salt sensible energy transmission and storage system design and costs

International Nuclear Information System (INIS)

1981-09-01

This report, which was prepared for Gas-Cooled Reactor Associates by United Engineers and Constructors under Contract No. GCRA/UE and C 81-203, presents the design and cost for a molten salt Sensible Energy Transmission and Storage (SETS) System. Although the reference system for this study is sized to be compatible with an 1170 MW(t) HTGR Nuclear Heat Source, the results and conclusions should be generally applicable to most large scale molten salt energy transmission system applications. A preliminary conceptual design is presented and alternative configurations are discussed. The sensitivity of system costs to variations in important system parameters are also presented. Costs for a reference case conceptual design are reported in constant 1980 dollars and inflated 1995 dollars

Palatini wormholes and energy conditions from the prism of general relativity

Energy Technology Data Exchange (ETDEWEB)

Bejarano, Cecilia [Instituto de Astronomia y Fisica del Espacio (IAFE, CONICET-UBA), Buenos Aires (Argentina); Centro Mixto Universidad de Valencia-CSIC. Universidad de Valencia, Departamento de Fisica Teorica y IFIC, Valencia (Spain); Lobo, Francisco S.N.; Rubiera-Garcia, Diego [Faculdade de Ciencias da Universidade de Lisboa, Instituto de Astrofisica e Ciencias do Espaco, Lisbon (Portugal); Olmo, Gonzalo J. [Centro Mixto Universidad de Valencia-CSIC. Universidad de Valencia, Departamento de Fisica Teorica y IFIC, Valencia (Spain); Universidade Federal da Paraiba, Departamento de Fisica, Joao Pessoa, Paraiba (Brazil)

2017-11-15

Wormholes are hypothetical shortcuts in spacetime that in general relativity unavoidably violate all of the pointwise energy conditions. In this paper, we consider several wormhole spacetimes that, as opposed to the standard designer procedure frequently employed in the literature, arise directly from gravitational actions including additional terms resulting from contractions of the Ricci tensor with the metric, and which are formulated assuming independence between metric and connection (Palatini approach). We reinterpret such wormhole solutions under the prism of General Relativity and study the matter sources that thread them. We discuss the size of violation of the energy conditions in different cases and how this is related to the same spacetimes when viewed from the modified gravity side. (orig.)

Palatini wormholes and energy conditions from the prism of general relativity.

Science.gov (United States)

Bejarano, Cecilia; Lobo, Francisco S N; Olmo, Gonzalo J; Rubiera-Garcia, Diego

2017-01-01

Wormholes are hypothetical shortcuts in spacetime that in general relativity unavoidably violate all of the pointwise energy conditions. In this paper, we consider several wormhole spacetimes that, as opposed to the standard designer procedure frequently employed in the literature, arise directly from gravitational actions including additional terms resulting from contractions of the Ricci tensor with the metric, and which are formulated assuming independence between metric and connection (Palatini approach). We reinterpret such wormhole solutions under the prism of General Relativity and study the matter sources that thread them. We discuss the size of violation of the energy conditions in different cases and how this is related to the same spacetimes when viewed from the modified gravity side.

Control of Solar Energy Systems

CERN Document Server

Camacho, Eduardo F; Rubio, Francisco R; Martínez, Diego

2012-01-01

Control of Solar Energy Systems details the main solar energy systems, problems involved with their control, and how control systems can help in increasing their efficiency.  After a brief introduction to the fundamental concepts associated with the use of solar energy in both photovoltaic and thermal plants, specific issues related to control of solar systems are embarked upon. Thermal energy systems are then explored in depth, as well as  other solar energy applications such as solar furnaces and solar refrigeration systems. Problems of variable generation profile and of the contribution of many solar plants to the same grid system are considered with the necessary integrated and supervisory control solutions being discussed. The text includes material on: ·         A comparison of basic and advanced control methods for parabolic troughs from PID to nonlinear model-based control; ·         solar towers and solar tracking; ·         heliostat calibration, characterization and off...

An energy management system for off-grid power systems

Energy Technology Data Exchange (ETDEWEB)

Zelazo, Daniel [Universitaet Stuttgart, Institute for Systems Theory and Automatic Control, Stuttgart (Germany); Dai, Ran; Mesbahi, Mehran [University of Washington, Department of Aeronautics and Astronautics, Seattle, WA (United States)

2012-06-15

Next generation power management at all scales will rely on the efficient scheduling and operation of both generating units and loads to maximize efficiency and utility. The ability to schedule and modulate the demand levels of a subset of loads within a power system can lead to more efficient use of the generating units. These methods become increasingly important for systems that operate independently of the main utility, such as microgrid and off-grid systems. This work extends the principles of unit commitment and economic dispatch problems to off-grid power systems where the loads are also schedulable. We propose a general optimization framework for solving the energy management problem in these systems. An important contribution is the description of how a wide range of sources and loads, including those with discrete states, non-convex, and nonlinear cost or utility functions, can be reformulated as a convex optimization problem using, for example, a shortest path description. Once cast in this way, solution are obtainable using a sub-gradient algorithm that also lends itself to a distributed implementation. The methods are demonstrated by a simulation of an off-grid solar powered community. (orig.)

Modelling and analysis of a novel compressed air energy storage system for trigeneration based on electrical energy peak load shifting

International Nuclear Information System (INIS)

Lv, Song; He, Wei; Zhang, Aifeng; Li, Guiqiang; Luo, Bingqing; Liu, Xianghua

2017-01-01

Highlights: • A new CAES system for trigeneration based on electrical peak load shifting is proposed. • The theoretical models and the thermodynamics process are established and analyzed. • The relevant parameters influencing its performance have been discussed and optimized. • A novel energy and economic evaluation methods is proposed to evaluate the performance of the system. - Abstract: The compressed air energy storage (CAES) has made great contribution to both electricity and renewable energy. In the pursuit of reduced energy consumption and relieving power utility pressure effectively, a novel trigeneration system based on CAES for cooling, heating and electricity generation by electrical energy peak load shifting is proposed in this paper. The cooling power is generated by the direct expansion of compressed air, and the heating power is recovered in the process of compression and storage. Based on the working principle of the typical CAES, the theoretical analysis of the thermodynamic system models are established and the characteristics of the system are analyzed. A novel method used to evaluate energy and economic performance is proposed. A case study is conducted, and the economic-social and technical feasibility of the proposed system are discussed. The results show that the trigeneration system works efficiently at relatively low pressure, and the efficiency is expected to reach about 76.3% when air is compressed and released by 15 bar. The annual monetary cost saving annually is about 53.9%. Moreover, general considerations about the proposed system are also presented.

Proceedings of the 1. General Congress of Nuclear Energy. v. 1

International Nuclear Information System (INIS)

1986-01-01

The proceedings of 1 General Congress of Nuclear Energy are presented. All fields related to nuclear energy are enclosed. In the first part the following fields are shown: safety analysis, science and technology of materials, nuclear materials, nuclear laws, education and trainning, reactor physics, nuclear physics, quality assurance, mathematical models, reactor operation, safeguards, advanced technologies, thermohydraulic and reactor licensing. (M.C.K.) [pt

Hybrid Energy System Modeling in Modelica

Energy Technology Data Exchange (ETDEWEB)

William R. Binder; Christiaan J. J. Paredis; Humberto E. Garcia

2014-03-01

In this paper, a Hybrid Energy System (HES) configuration is modeled in Modelica. Hybrid Energy Systems (HES) have as their defining characteristic the use of one or more energy inputs, combined with the potential for multiple energy outputs. Compared to traditional energy systems, HES provide additional operational flexibility so that high variability in both energy production and consumption levels can be absorbed more effectively. This is particularly important when including renewable energy sources, whose output levels are inherently variable, determined by nature. The specific HES configuration modeled in this paper include two energy inputs: a nuclear plant, and a series of wind turbines. In addition, the system produces two energy outputs: electricity and synthetic fuel. The models are verified through simulations of the individual components, and the system as a whole. The simulations are performed for a range of component sizes, operating conditions, and control schemes.

Sustainable Energy Systems and Applications

CERN Document Server

Dinçer, İbrahim

2012-01-01

Sustainable Energy Systems and Applications presents analyses of sustainable energy systems and their applications, providing new understandings, methodologies, models and applications along with descriptions of several illustrative examples and case studies. This textbook aims to address key pillars in the field, such as: better efficiency, cost effectiveness, use of energy resources, environment, energy security, and sustainable development. It also includes some cutting-edge topics, such as hydrogen and fuel cells, renewable, clean combustion technologies, CO2 abatement technologies, and some potential tools for design, analysis and performance improvement. The book also: Discusses producing energy by increasing systems efficiency in generation, conversion, transportation and consumption Analyzes the conversion of fossil fuels to clean fuels for limiting  pollution and creating a better environment Sustainable Energy Systems and Applications is a research-based textbook which can be used by senior u...

Feasibility study on an energy-saving desiccant wheel system with CO2 heat pump

Science.gov (United States)

Liu, Yefeng; Meng, Deren; Chen, Shen

2018-02-01

In traditional desiccant wheel, air regeneration process occurs inside an open loop, and lots of energy is consumed. In this paper, an energy-saving desiccant wheel system with CO2 heat pump and closed loop air regeneration is proposed. The general theory and features of the desiccant wheel are analysed. The main feature of the proposed system is that the air regeneration process occurs inside a closed loop, and a CO2 heat pump is utilized inside this loop for the air regeneration process as well as supplying cooling for the process air. The simulation results show that the proposed system can save significant energy.

Energy Conversion Alternatives Study (ECAS), General Electric Phase 1. Volume 2: Advanced energy conversion systems. Part 1: Open-cycle gas turbines

Science.gov (United States)

Brown, D. H.; Corman, J. C.

1976-01-01

Ten energy conversion systems are defined and analyzed in terms of efficiency. These include: open-cycle gas turbine recuperative; open-cycle gas turbine; closed-cycle gas turbine; supercritical CO2 cycle; advanced steam cycle; liquid metal topping cycle; open-cycle MHD; closed-cycle inert gas MHD; closed-cycle liquid metal MHD; and fuel cells. Results are presented.

Analysis of Generalized Ghost Dark Energy in LQC and Galileon Gravity

International Nuclear Information System (INIS)

Biswas, Mahasweta; Debnath, Ujjal

2016-01-01

A so-called ghost dark energy was recently proposed to explain the present acceleration of the universe. The energy density of ghost dark energy, which originates from Veneziano ghost of Quantum Chromodynamics (QCD), in a time dependent background, can be written in the form, ρ_D = (αH + βH"2) where H is the Hubble parameter. We investigate the generalized ghost dark energy (GGDE) model in the setup of loop quantum Cosmology (LQC) and Galileon Cosmology. We study the cosmological implications of the models. We also obtain the equation of state and the deceleration parameters and differential equations governing the evolution of this dark energy model for LQC and Galileon Cosmology. (paper)

A field experiment of energy education using integrative learning support system

International Nuclear Information System (INIS)

Obayashi, Fumiaki; Yamamoto, Atsumu; Ito, Kyoko; Shimoda, Hiroshi; Yoshikawa, Hidekazu

2002-01-01

A new energy learning support system for higher education was the object of this experiment. The aim of this learning support system is to support students within an integrative study environment in which various personal skills and general knowledge on energy related issues are to be developed. The main goals of this learning tool for the students are to simulate their interest and creativity, to enhance awareness, to increase capability of researching on the subject and to improve problem-solving skills on energy related issues. The salient feature of this learning support system is that it is used for group learning by which each learner can develop the ability to reflect on the subject through mutual discussion. Moreover, in order to keep the attention of the students on the topic and provide them with a better assimilation of the curriculum, a personified agent is used as a cooperative associate who assists learners through natural communication, using voice conversation function in Japanese language. Then, the subject experiment has been conducted. Also, means of effective energy education are discussed in this research. As a conclusion, this learning support system is proven to be effective and the use of it for energy education is recommended. (author)

Design study of general aviation collision avoidance system

Science.gov (United States)

Bates, M. R.; Moore, L. D.; Scott, W. V.

1972-01-01

The selection and design of a time/frequency collision avoidance system for use in general aviation aircraft is discussed. The modifications to airline transport collision avoidance equipment which were made to produce the simpler general aviation system are described. The threat determination capabilities and operating principles of the general aviation system are illustrated.

Active motions of Brownian particles in a generalized energy-depot model

International Nuclear Information System (INIS)

Zhang Yong; Koo Kim, Chul; Lee, Kong-Ju-Bock

2008-01-01

We present a generalized energy-depot model in which the rate of conversion of the internal energy into motion can be dependent on the position and velocity of a particle. When the conversion rate is a general function of the velocity, the active particle exhibits diverse patterns of motion, including a braking mechanism and a stepping motion. The phase trajectories of the motion are investigated in a systematic way. With a particular form of the conversion rate dependent on the position and velocity, the particle shows a spontaneous oscillation characterizing a negative stiffness. These types of active behaviors are compared with similar phenomena observed in biology, such as the stepping motion of molecular motors and amplification in the hearing mechanism. Hence, our model can provide a generic understanding of the active motion related to the energy conversion and also a new control mechanism for nano-robots. We also investigate the effect of noise, especially on the stepping motion, and observe random walk-like behavior as expected.