Use of GMM and SCMS for Accurate Road Centerline Extraction from the Classified Image

Directory of Open Access Journals (Sweden)

Zelang Miao

2015-01-01

Full Text Available The extraction of road centerline from the classified image is a fundamental image analysis technology. Common problems encountered in road centerline extraction include low ability for coping with the general case, production of undesired objects, and inefficiency. To tackle these limitations, this paper presents a novel accurate centerline extraction method using Gaussian mixture model (GMM and subspace constraint mean shift (SCMS. The proposed method consists of three main steps. GMM is first used to partition the classified image into several clusters. The major axis of the ellipsoid of each cluster is extracted and deemed to be taken as the initial centerline. Finally, the initial result is adjusted using SCMS to produce precise road centerline. Both simulated and real datasets are used to validate the proposed method. Preliminary results demonstrate that the proposed method provides a comparatively robust solution for accurate centerline extraction from a classified image.

Intertwined nanocarbon and manganese oxide hybrid foam for high-energy supercapacitors.

Science.gov (United States)

Wang, Wei; Guo, Shirui; Bozhilov, Krassimir N; Yan, Dong; Ozkan, Mihrimah; Ozkan, Cengiz S

2013-11-11

Rapid charging and discharging supercapacitors are promising alternative energy storage systems for applications such as portable electronics and electric vehicles. Integration of pseudocapacitive metal oxides with single-structured materials has received a lot of attention recently due to their superior electrochemical performance. In order to realize high energy-density supercapacitors, a simple and scalable method is developed to fabricate a graphene/MWNT/MnO2 nanowire (GMM) hybrid nanostructured foam, via a two-step process. The 3D few-layer graphene/MWNT (GM) architecture is grown on foamed metal foils (nickel foam) via ambient pressure chemical vapor deposition. Hydrothermally synthesized α-MnO2 nanowires are conformally coated onto the GM foam by a simple bath deposition. The as-prepared hierarchical GMM foam yields a monographical graphene foam conformally covered with an intertwined, densely packed CNT/MnO2 nanowire nanocomposite network. Symmetrical electrochemical capacitors (ECs) based on GMM foam electrodes show an extended operational voltage window of 1.6 V in aqueous electrolyte. A superior energy density of 391.7 Wh kg(-1) is obtained for the supercapacitor based on the GMM foam, which is much higher than ECs based on GM foam only (39.72 Wh kg(-1) ). A high specific capacitance (1108.79 F g(-1) ) and power density (799.84 kW kg(-1) ) are also achieved. Moreover, the great capacitance retention (97.94%) after 13 000 charge-discharge cycles and high current handability demonstrate the high stability of the electrodes of the supercapacitor. These excellent performances enable the innovative 3D hierarchical GMM foam to serve as EC electrodes, resulting in energy-storage devices with high stability and power density in neutral aqueous electrolyte. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Superioridad relativa de los estimadores Kiviet y Blundell-Bond (GMM1 en paneles dinámicos. Un experimento Monte Carlo con muestras finitas

Directory of Open Access Journals (Sweden)

Andrés Eduardo Rangel Jiménez

2012-10-01

Full Text Available Dado el amplio uso de los datos de panel en modelos dinamicos, es relevante evaluar el desempeno de sus diferentes estimadores en muestras finitas en presencia de baja y alta persistencia. El presente articulo tiene como objetivo analizar, mediante simulaciones tipo Monte Carlo, las propiedades de los estimadores de efectos fijos (LSDV, Arellano y Bond (AB-GMM1, Blundell y Bond (BB-GMM1, Anderson y Hsiao (AH y Kiviet. Se concluye que en series no persistentes el estimador de Kiviet es el de mejor desempeno, basandose en los criterios de error cuadratico medio, sesgo y desviacion estandar; con alta persistencia, el estimador BB-GMM1 es el de mejor desempeno seguido por el estimador de Kiviet, que se comporta bien excepto en micropaneles con series persistentes.

Acoustics based assessment of respiratory diseases using GMM classification.

Science.gov (United States)

Mayorga, P; Druzgalski, C; Morelos, R L; Gonzalez, O H; Vidales, J

2010-01-01

The focus of this paper is to present a method utilizing lung sounds for a quantitative assessment of patient health as it relates to respiratory disorders. In order to accomplish this, applicable traditional techniques within the speech processing domain were utilized to evaluate lung sounds obtained with a digital stethoscope. Traditional methods utilized in the evaluation of asthma involve auscultation and spirometry, but utilization of more sensitive electronic stethoscopes, which are currently available, and application of quantitative signal analysis methods offer opportunities of improved diagnosis. In particular we propose an acoustic evaluation methodology based on the Gaussian Mixed Models (GMM) which should assist in broader analysis, identification, and diagnosis of asthma based on the frequency domain analysis of wheezing and crackles.

Expansions of GMM statistics that indicate their properties under weak and/or many instruments and the bootstrap

NARCIS (Netherlands)

Kleibergen, F.R.

2003-01-01

We show that the sensitivity of the limit distribution of commonly used GMM statistics to weak and many instruments results from superfluous elements in the higher order expansion of these statistics. When the instruments are strong and their number is small, these elements are of higher order and

On the determinants of renewable energy consumption: International Evidence

OpenAIRE

Anis Omri; Duc Khuong Nguyen

2014-01-01

Over recent years, renewable energy sources have emerged as an important component of world energy consumption. Little is however known about the determinants of renewable energy consumption. This article tackles this issue for a global panel consisting of 64 countries over the period 1990-2011 by using a dynamic system- GMM panel model. We also consider three homogeneous subpanels which are constructed based on the income level of sample countries (high-, middle-, and low-income subpanels). ...

A GMM-Based Test for Normal Disturbances of the Heckman Sample Selection Model

Directory of Open Access Journals (Sweden)

Michael Pfaffermayr

2014-10-01

Full Text Available The Heckman sample selection model relies on the assumption of normal and homoskedastic disturbances. However, before considering more general, alternative semiparametric models that do not need the normality assumption, it seems useful to test this assumption. Following Meijer and Wansbeek (2007, the present contribution derives a GMM-based pseudo-score LM test on whether the third and fourth moments of the disturbances of the outcome equation of the Heckman model conform to those implied by the truncated normal distribution. The test is easy to calculate and in Monte Carlo simulations it shows good performance for sample sizes of 1000 or larger.

Planning and design of a knowledge based system for green manufacturing management

Science.gov (United States)

Kamal Mohd Nawawi, Mohd; Mohd Zuki Nik Mohamed, Nik; Shariff Adli Aminuddin, Adam

2013-12-01

This paper presents a conceptual design approach to the development of a hybrid Knowledge Based (KB) system for Green Manufacturing Management (GMM) at the planning and design stages. The research concentrates on the GMM by using a hybrid KB system, which is a blend of KB system and Gauging Absences of Pre-requisites (GAP). The hybrid KB/GAP system identifies all potentials elements of green manufacturing management issues throughout the development of this system. The KB system used in the planning and design stages analyses the gap between the existing and the benchmark organizations for an effective implementation through the GAP analysis technique. The proposed KBGMM model at the design stage explores two components, namely Competitive Priority and Lean Environment modules. Through the simulated results, the KBGMM System has identified, for each modules and sub-module, the problem categories in a prioritized manner. The System finalized all the Bad Points (BP) that need to be improved to achieve benchmark implementation of GMM at the design stage. The System provides valuable decision making information for the planning and design a GMM in term of business organization.

Planning and design of a knowledge based system for green manufacturing management

International Nuclear Information System (INIS)

Nawawi, Mohd Kamal Mohd; Mohamed, Nik Mohd Zuki Nik; Aminuddin, Adam Shariff Adli

2013-01-01

This paper presents a conceptual design approach to the development of a hybrid Knowledge Based (KB) system for Green Manufacturing Management (GMM) at the planning and design stages. The research concentrates on the GMM by using a hybrid KB system, which is a blend of KB system and Gauging Absences of Pre-requisites (GAP). The hybrid KB/GAP system identifies all potentials elements of green manufacturing management issues throughout the development of this system. The KB system used in the planning and design stages analyses the gap between the existing and the benchmark organizations for an effective implementation through the GAP analysis technique. The proposed KBGMM model at the design stage explores two components, namely Competitive Priority and Lean Environment modules. Through the simulated results, the KBGMM System has identified, for each modules and sub-module, the problem categories in a prioritized manner. The System finalized all the Bad Points (BP) that need to be improved to achieve benchmark implementation of GMM at the design stage. The System provides valuable decision making information for the planning and design a GMM in term of business organization

Capital mobility in the panel GMM framework: Evidence from EU members

Directory of Open Access Journals (Sweden)

Natalya Ketenci

2015-06-01

Full Text Available This paper examines the level of international capital mobility in European Union members under the Feldstein and Horioka (1980 hypothesis. The validity of the Feldstein-Horioka puzzle is investigated taking into account the impact of the global financial crisis employing the generalized method of moments (GMM estimation technique developed by Hansen (1982. In general, the world countries with time have a tendency to a higher level of capital market openness. According to Feldstein and Horioka (1980, a higher saving-investment correlation is related to lower capital mobility. In this paper, panel data for 27 European countries were used for the period of 1995-2013 on the quarterly basis. The empirical results provide evidence of high capital mobility in EU members, obtaining a low value of a saving retention coefficient. The results of estimations indicate significant dependence of investments on its past values. It is found that the global financial crisis had a deeply negative impact on investment rates in 2007 and for the general period of 2007-2013. The empirical results indicate that the level of capital mobility increased during the global financial crisis, 2007-2013. Thus decrease in investments and increase in the international capital mobility level of European countries during the period of the global financial crisis of 2007-2013, taking into account high risk in the international market, indicates a reallocation of capital from international to regional markets.

An Iterated GMM Procedure for Estimating the Campbell-Cochrane Habit Formation Model, with an Application to Danish Stock and Bond Returns

DEFF Research Database (Denmark)

Engsted, Tom; Møller, Stig Vinther

2010-01-01

We suggest an iterated GMM approach to estimate and test the consumption based habit persistence model of Campbell and Cochrane, and we apply the approach on annual and quarterly Danish stock and bond returns. For comparative purposes we also estimate and test the standard constant relative risk...... covering more than 80 years there is absolutely no evidence of superior performance of the Campbell-Cochrane model. For the shorter and more recent quarterly data over a 20-30 year period, there is some evidence of counter-cyclical time-variation in the degree of risk-aversion, in accordance...

An iterated GMM procedure for estimating the Campbell-Cochrane habit formation model, with an application to Danish stock and bond returns

DEFF Research Database (Denmark)

Engsted, Tom; Møller, Stig V.

We suggest an iterated GMM approach to estimate and test the consumption based habit persistence model of Campbell and Cochrane (1999), and we apply the approach on annual and quarterly Danish stock and bond returns. For comparative purposes we also estimate and test the standard CRRA model...... than 80 years there is absolutely no evidence of superior performance of the Campbell-Cochrane model. For the shorter and more recent quarterly data over a 20-30 year period, there is some evidence of counter-cyclical time-variation in the degree of risk-aversion, in accordance with the Campbell...

Fast Rotation-Free Feature-Based Image Registration Using Improved N-SIFT and GMM-Based Parallel Optimization.

Science.gov (United States)

Yu, Dongdong; Yang, Feng; Yang, Caiyun; Leng, Chengcai; Cao, Jian; Wang, Yining; Tian, Jie

2016-08-01

Image registration is a key problem in a variety of applications, such as computer vision, medical image processing, pattern recognition, etc., while the application of registration is limited by time consumption and the accuracy in the case of large pose differences. Aimed at these two kinds of problems, we propose a fast rotation-free feature-based rigid registration method based on our proposed accelerated-NSIFT and GMM registration-based parallel optimization (PO-GMMREG). Our method is accelerated by using the GPU/CUDA programming and preserving only the location information without constructing the descriptor of each interest point, while its robustness to missing correspondences and outliers is improved by converting the interest point matching to Gaussian mixture model alignment. The accuracy in the case of large pose differences is settled by our proposed PO-GMMREG algorithm by constructing a set of initial transformations. Experimental results demonstrate that our proposed algorithm can fast rigidly register 3-D medical images and is reliable for aligning 3-D scans even when they exhibit a poor initialization.

Juxtaposition of micro and macro dynamics of dividend policy on stock price volatility in financial sector of Pakistan : (comparative analysis through common, fixed, random and GMM effect)

OpenAIRE

Hamid, Kashif; Khurram, Muhammad Usman; Ghaffar, Wasim

2017-01-01

The purpose of this study is to analyze the dividend policy dynamics in context to firm specific and macroeconomic variables with stock price volatility in the financial sector of Pakistan. Panel data is used for the period 2006-2014 to identify the common, fixed, random and GMM effect. It is concluded that dividend payout ratio, market value, interest volatility and inflation volatility have positive significant correlation with price volatility. Common effect model shows that dividend payou...

Distributed Energy Generation Systems Based on Renewable Energy and Natural Gas Blending: New Business Models for Economic Incentives, Electricity Market Design and Regulatory Innovation

Science.gov (United States)

Nyangon, Joseph

Expansion of distributed energy resources (DERs) including solar photovoltaics, small- and medium-sized wind farms, gas-fired distributed generation, demand-side management, and energy storage poses significant complications to the design, operation, business model, and regulation of electricity systems. Using statistical regression analysis, this dissertation assesses if increased use of natural gas results in reduced renewable energy capacity, and if natural gas growth is correlated with increased or decreased non-fossil renewable fuels demand. System Generalized Method of Moments (System GMM) estimation of the dynamic relationship was performed on the indicators in the econometric model for the ten states with the fastest growth in solar generation capacity in the U.S. (e.g., California, North Carolina, Arizona, Nevada, New Jersey, Utah, Massachusetts, Georgia, Texas, and New York) to analyze the effect of natural gas on renewable energy diffusion and the ratio of fossil fuels increase for the period 2001-2016 to policy driven solar demand. The study identified ten major drivers of change in electricity systems, including growth in distributed energy generation systems such as intermittent renewable electricity and gas-fired distributed generation; flat to declining electricity demand growth; aging electricity infrastructure and investment gaps; proliferation of affordable information and communications technologies (e.g., advanced meters or interval meters), increasing innovations in data and system optimization; and greater customer engagement. In this ongoing electric power sector transformation, natural gas and fast-flexing renewable resources (mostly solar and wind energy) complement each other in several sectors of the economy. The dissertation concludes that natural gas has a positive impact on solar and wind energy development: a 1% rise in natural gas capacity produces 0.0304% increase in the share of renewable energy in the short-run (monthly) compared

Fiscal Deficit, National Saving and Sustainability of Economic Growth in Emerging Economies: A Dynamic GMM Panel Data Approach

Directory of Open Access Journals (Sweden)

Buscemi Antonino

2012-01-01

Full Text Available The neoclassical growth models argued that the movement to steady states; technology, exogenous rate of savings, population growth and technical progress stimulate higher growth levels (Solow 1956. Contrary to the neoclassical argument, endogenous growth model argues that, in the theory of endogenous growth, government play a significant role in promoting accumulation of knowledge, research and development, public investment, human capital development, law and order can generate growth both in the short and long run. Moreover, they assumed technical progress as endogenous variable for growth (Barro 1995. This study analyze the effects of fiscal deficit on sustainability of economic growth and provided new empirical evidence on the effects of fiscal deficit on saving and sustainability of economic growth based on the assumption of endogenous growth model. We estimated using the reduced form of GMM method for dynamic panels covers 1990-2009 for three emerging countries that includes China, India and South Africa.

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...

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

Energy Systems Integration Facility News | Energy Systems Integration

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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

Impact of Energy Consumption on Economic Growth in Major OECD Economies (1977-2014): A Panel Data Approach

OpenAIRE

Aali-Bujari, Alí; Venegas-Martínez, Francisco; Palafox-Roca, Alfredo Omar

2017-01-01

This paper is aimed at assessing the impact of energy use growth on economic growth in the major economies of the Organization for Economic Cooperation and Development (OECD) during the period 1977-2014. To do this, a Granger causality analysis among relevant variables is carried out and, subsequently, a panel data model is estimated with the Generalized Method of Moments (GMM). The main empirical finding is that real GDP per capita growth is positively affected by the growth rate of energy u...

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

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...

GMM - a general microstructural model for qualitative and quantitative studies of smectite clays

International Nuclear Information System (INIS)

Pusch, R.; Karnland, O.; Hoekmark, H.

1990-12-01

A few years ago an attempt was made to accommodate a number of basic ideas on the fabric and interparticle forces that are assumed to be valid in montmorillonite clay in an integrated microstructural model and this resulted in an SKB report on 'Outlines of models of water and gas flow through smectite clay buffers'. This model gave reasonable agreement between predicted hydraulic conductivity values and actually recorded ones for room temperature and porewater that is poor in electrolytes. The present report describes an improved model that also accounts for effects generated by salt porewater and heating, and that provides a basis for both quantitative determination of transport capacities in a more general way, and also for analysis and prediction of rheological behaviour in bulk. It has been understood very early by investigators in this scientific field that full understanding of the physical state of porewater is asked for in order to make it possible to develop models for clay particle interaction. In particular, a deep insight in the nature of the interlamellar water and of the hydration mechanisms leading to an equilibrium state between the two types of water, and of forcefields in matured smectite clay, requires very qualified multi-discipline research and attempts have been made by the senior author to initiate and coordinate such work in the last 30 years. Despite this effort it has not been possible to get an unanimous understanding of these things but a number of major features have become more clear through the work that we have been able to carry out in the current SKB research work. Thus, NMR studies and precision measurements of the density of porewater as well as comprehensive electron microscopy and rheological testing in combination with application of stochastical mechanics, have led to the hypothetical microstructural model - the GMM - presented in this report. (au)

Energy Systems Integration Facility Videos | Energy Systems Integration

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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

Th1-skewed tissue responses to a mycolyl glycolipid in mycobacteria-infected rhesus macaques

Energy Technology Data Exchange (ETDEWEB)

Morita, Daisuke; Miyamoto, Ayumi; Hattori, Yuki; Komori, Takaya [Laboratory of Cell Regulation, Institute for Virus Research, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507 (Japan); Nakamura, Takashi [Faculty of Pharmaceutical Sciences, Hokkaido University, Kita 12 Nishi 6, Kita-ku, Sapporo, Hokkaido 060-0812 (Japan); Igarashi, Tatsuhiko [Laboratory of Primate Model, Institute for Virus Research, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507 (Japan); Harashima, Hideyoshi [Faculty of Pharmaceutical Sciences, Hokkaido University, Kita 12 Nishi 6, Kita-ku, Sapporo, Hokkaido 060-0812 (Japan); Sugita, Masahiko [Laboratory of Cell Regulation, Institute for Virus Research, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507 (Japan)

2013-11-08

Highlights: •Glucose monomycolate (GMM) is a marker glycolipid for active tuberculosis. •Tissue responses to GMM involved up-regulation of Th1-attracting chemokines. •Th1-skewed local responses were mounted at the GMM-injected tissue. -- Abstract: Trehalose 6,6′-dimycolate (TDM) is a major glycolipid of the cell wall of mycobacteria with remarkable adjuvant functions. To avoid detection by the host innate immune system, invading mycobacteria down-regulate the expression of TDM by utilizing host-derived glucose as a competitive substrate for their mycolyltransferases; however, this enzymatic reaction results in the concomitant biosynthesis of glucose monomycolate (GMM) which is recognized by the acquired immune system. GMM-specific, CD1-restricted T cell responses have been detected in the peripheral blood of infected human subjects and monkeys as well as in secondary lymphoid organs of small animals, such as guinea pigs and human CD1-transgenic mice. Nevertheless, it remains to be determined how tissues respond at the site where GMM is produced. Here we found that rhesus macaques vaccinated with Mycobacterium bovis bacillus Calmette–Guerin mounted a chemokine response in GMM-challenged skin that was favorable for recruiting T helper (Th)1 T cells. Indeed, the expression of interferon-γ, but not Th2 or Th17 cytokines, was prominent in the GMM-injected tissue. The GMM-elicited tissue response was also associated with the expression of monocyte/macrophage-attracting CC chemokines, such as CCL2, CCL4 and CCL8. Furthermore, the skin response to GMM involved the up-regulated expression of granulysin and perforin. Given that GMM is produced primarily by pathogenic mycobacteria proliferating within the host, the Th1-skewed tissue response to GMM may function efficiently at the site of infection.

Th1-skewed tissue responses to a mycolyl glycolipid in mycobacteria-infected rhesus macaques

International Nuclear Information System (INIS)

Morita, Daisuke; Miyamoto, Ayumi; Hattori, Yuki; Komori, Takaya; Nakamura, Takashi; Igarashi, Tatsuhiko; Harashima, Hideyoshi; Sugita, Masahiko

2013-01-01

Highlights: •Glucose monomycolate (GMM) is a marker glycolipid for active tuberculosis. •Tissue responses to GMM involved up-regulation of Th1-attracting chemokines. •Th1-skewed local responses were mounted at the GMM-injected tissue. -- Abstract: Trehalose 6,6′-dimycolate (TDM) is a major glycolipid of the cell wall of mycobacteria with remarkable adjuvant functions. To avoid detection by the host innate immune system, invading mycobacteria down-regulate the expression of TDM by utilizing host-derived glucose as a competitive substrate for their mycolyltransferases; however, this enzymatic reaction results in the concomitant biosynthesis of glucose monomycolate (GMM) which is recognized by the acquired immune system. GMM-specific, CD1-restricted T cell responses have been detected in the peripheral blood of infected human subjects and monkeys as well as in secondary lymphoid organs of small animals, such as guinea pigs and human CD1-transgenic mice. Nevertheless, it remains to be determined how tissues respond at the site where GMM is produced. Here we found that rhesus macaques vaccinated with Mycobacterium bovis bacillus Calmette–Guerin mounted a chemokine response in GMM-challenged skin that was favorable for recruiting T helper (Th)1 T cells. Indeed, the expression of interferon-γ, but not Th2 or Th17 cytokines, was prominent in the GMM-injected tissue. The GMM-elicited tissue response was also associated with the expression of monocyte/macrophage-attracting CC chemokines, such as CCL2, CCL4 and CCL8. Furthermore, the skin response to GMM involved the up-regulated expression of granulysin and perforin. Given that GMM is produced primarily by pathogenic mycobacteria proliferating within the host, the Th1-skewed tissue response to GMM may function efficiently at the site of infection

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

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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

Energy consumption, political regime and economic growth in sub-Saharan Africa

International Nuclear Information System (INIS)

Adams, Samuel; Klobodu, Edem Kwame Mensah; Opoku, Eric Evans Osei

2016-01-01

In this paper, we examine the relationship between energy consumption and economic growth, and how democracy moderates this relationship using panel data of 16 sub-Saharan African (SSA) countries for the period 1971–2013. Employing a panel vector autoregressive model (PVAR) in a generalized method of moments (GMM) framework, the findings support the feedback hypothesis for energy consumption and growth. Second, the interaction variable (energy consumption and democracy) is positively and significantly related to economic growth, supporting the view that democracy moderates the energy consumption and growth nexus. Further, the results provide strong evidence of a uni-directional relationship from trade openness to energy consumption. Additionally, impulse responses and variance decompositions also confirm positive feedback relationships between energy consumption and economic growth, energy prices and economic growth. - Highlights: •Feedback exists between energy consumption and economic growth. •Democracy moderates the energy consumption and growth nexus. •positive feedback between energy prices and economic growth. •Uni-directional relationship from openness to energy consumption.

A Gaussian mixture model based cost function for parameter estimation of chaotic biological systems

Science.gov (United States)

Shekofteh, Yasser; Jafari, Sajad; Sprott, Julien Clinton; Hashemi Golpayegani, S. Mohammad Reza; Almasganj, Farshad

2015-02-01

As we know, many biological systems such as neurons or the heart can exhibit chaotic behavior. Conventional methods for parameter estimation in models of these systems have some limitations caused by sensitivity to initial conditions. In this paper, a novel cost function is proposed to overcome those limitations by building a statistical model on the distribution of the real system attractor in state space. This cost function is defined by the use of a likelihood score in a Gaussian mixture model (GMM) which is fitted to the observed attractor generated by the real system. Using that learned GMM, a similarity score can be defined by the computed likelihood score of the model time series. We have applied the proposed method to the parameter estimation of two important biological systems, a neuron and a cardiac pacemaker, which show chaotic behavior. Some simulated experiments are given to verify the usefulness of the proposed approach in clean and noisy conditions. The results show the adequacy of the proposed cost function.

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

Generalized matrix method for transmission of neutrons through multilayer magnetic system with non-colinear magnetization

International Nuclear Information System (INIS)

Radu, F.; Ignatovich, V.K.

1999-01-01

A generalized matrix method (GMM) for reflection and transmission of polarized and nonpolarized neutrons for multilayer systems with non-colinear magnetization of neighboring layers is developed. Several methods exist for calculation of the reflection and transmission coefficients of the multilayer systems (MS). We consider here only two of them. One is the recurrence method (RM), and another one is the matrix method. Previously these methods were used for scalar particles and for spinor particles. In the last case a limitation was imposed on the directions of the magnetization of different layers: they were required to lie in the plane parallel to the layers. In 1995 Fermon has described a different approach of the neutrons in MS. Here, the behaviour of the wave inside the layers depends on the position within the plane. The RM, as shown by us earlier, permits to treat multilayer systems with arbitrary directions of the magnetization. We show how to treat these systems with the updated matrix method, which we call the generalized matrix method. In the GMM method the transmission and reflection of a layered system are obtained by finding a 4 x 4 matrix, which is a product of elementary 4 x 4 matrices related to the different layers, and in the RM the solution is found by recurrent application of the same procedure of finding the reflection and transmission matrices for a continuously increasing number of layers. The RM method permits to use a simple algorithm to write analytical formulas for the reflection and transmission. However, for more or less complicated systems these formulas become useless and one needs to do numerical calculations. The GMM does not give a simple analytical algorithm, but it gives a very simple numerical algorithm. We have developed two computer codes for computing the coefficients of reflection and transmission of a layered system using the GMM and RM methods. The calculated reflectivities R ++ and R +- for a polarized beam which fall on

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-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

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...

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...

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.

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

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

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

Impact of economic growth, nonrenewable and renewable energy consumption, and urbanization on carbon emissions in Sub-Saharan Africa.

Science.gov (United States)

Hanif, Imran

2018-05-01

The present study explores the impact of economic growth; urban expansion; and consumption of fossil fuels, solid fuels, and renewable energy on environmental degradation in developing economies of Sub-Saharan Africa. To demonstrate its findings in detail, the study adopts a system generalized method of moment (GMM) on a panel of 34 emerging economies for the period from 1995 to 2015. The results describe that the consumption of fossil and solid fuels for cooking and expansion of urban areas are significantly contributing to carbon dioxide emissions, on one end, and stimulating air pollution, on the other. The results also exhibit an inverted U-shape relationship between per capita economic growth and carbon emissions. This relation confirms the existence of an environmental Kuznets curve (EKC) in middle- and low-income economies of Sub-Saharan Africa. Furthermore, the findings reveal that the use of renewable energy alternatives improves air quality by controlling carbon emissions and lowering the direct interaction of households with toxic gases. Thus, the use of renewable energy alternatives helps the economies to achieve sustainable development targets.

Does moving towards renewable energy causes water and land inefficiency? An empirical investigation

International Nuclear Information System (INIS)

Al-mulali, Usama; Solarin, Sakiru Adebola; Sheau-Ting, Low; Ozturk, Ilhan

2016-01-01

This study investigates the effect of renewable energy production on water and land footprint in 58 developed and developing countries for the period of 1980–2009. Utilizing the ecological footprint as an indicator, the fixed effects, difference and system generalized method of moment (GMM) approaches were employed and eight different models were constructed to achieve robustness in the empirical outcomes. Despite the use of different methods and models, the outcome was the same whereby GDP growth, urbanization, and trade openness increase the water and land footprint. Moreover, renewable energy production increases the water and land inefficiency because of its positive effect on ecological footprint. Additionally, based on the square of GDP it is concluded that the EKC hypothesis does not exist while the square of renewable energy production indicates that renewable energy production will continue to increase water and land footprint in the future. From the outcome of this study, a number of recommendations were provided to the investigated countries. - Highlights: •The effect of renewable energy production on water and land footprint is studied. •58 developed and developing countries were examined for the period of 1980–2009. •Eight different models were constructed to achieve robustness in the outcomes. •GDP, urbanization, and trade openness increase the water and land footprint. •Renewable energy production increases the water and land inefficiency.

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 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

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

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)

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...

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

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.

High-speed cell recognition algorithm for ultrafast flow cytometer imaging system

Science.gov (United States)

Zhao, Wanyue; Wang, Chao; Chen, Hongwei; Chen, Minghua; Yang, Sigang

2018-04-01

An optical time-stretch flow imaging system enables high-throughput examination of cells/particles with unprecedented high speed and resolution. A significant amount of raw image data is produced. A high-speed cell recognition algorithm is, therefore, highly demanded to analyze large amounts of data efficiently. A high-speed cell recognition algorithm consisting of two-stage cascaded detection and Gaussian mixture model (GMM) classification is proposed. The first stage of detection extracts cell regions. The second stage integrates distance transform and the watershed algorithm to separate clustered cells. Finally, the cells detected are classified by GMM. We compared the performance of our algorithm with support vector machine. Results show that our algorithm increases the running speed by over 150% without sacrificing the recognition accuracy. This algorithm provides a promising solution for high-throughput and automated cell imaging and classification in the ultrafast flow cytometer imaging platform.

Causality between public policies and exports of renewable energy technologies

International Nuclear Information System (INIS)

Sung, Bongsuk; Song, Woo-Yong

2013-01-01

This article investigates the causal relationship between public policies and exports of renewable energy technologies using panel data from 18 countries for the period 1991–2007. A number of panel unit root and cointegration tests are applied. Time series data on public policies and exports are integrated and cointegrated. The dynamic OLS results indicate that in the long run, a 1% increase in government R and D expenditures (RAD) increases exports (EX) by 0.819%. EX and RAD variables respond to deviations from the long-run equilibrium in the previous period. Additionally, the Blundell–Bond system generalized methods of moments (GMM) is employed to conduct a panel causality test in a vector error-correction mechanism (VECM) setting. Evidence of a bidirectional and short-run, and strong causal relationship between EX and the contribution of renewable energy to the total energy supply (CRES) is uncovered. CRES has a negative effect on EX, whereas EX has a positive effect on CRES. We suggest some policy implications based on the results of this study. - Highlights: ► We model VECM to test the Granger causality between the policies and the export. ► Technology-push policy has a positive impact on export in the long-run. ► There are the short-run causal relationships between market-pull policy and export

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.

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

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.

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...

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...

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.

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.

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

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

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...

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.

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...

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 ...

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)

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)

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...

Tsetse immune system maturation requires the presence of obligate symbionts in larvae.

Directory of Open Access Journals (Sweden)

Brian L Weiss

2011-05-01

Full Text Available Beneficial microbial symbionts serve important functions within their hosts, including dietary supplementation and maintenance of immune system homeostasis. Little is known about the mechanisms that enable these bacteria to induce specific host phenotypes during development and into adulthood. Here we used the tsetse fly, Glossina morsitans, and its obligate mutualist, Wigglesworthia glossinidia, to investigate the co-evolutionary adaptations that influence the development of host physiological processes. Wigglesworthia is maternally transmitted to tsetse's intrauterine larvae through milk gland secretions. We can produce flies that lack Wigglesworthia (Gmm(Wgm- yet retain their other symbiotic microbes. Such offspring give rise to adults that exhibit a largely normal phenotype, with the exception being that they are reproductively sterile. Our results indicate that when reared under normal environmental conditions Gmm(Wgm- adults are also immuno-compromised and highly susceptible to hemocoelic E. coli infections while age-matched wild-type individuals are refractory. Adults that lack Wigglesworthia during larval development exhibit exceptionally compromised cellular and humoral immune responses following microbial challenge, including reduced expression of genes that encode antimicrobial peptides (cecropin and attacin, hemocyte-mediated processes (thioester-containing proteins 2 and 4 and prophenoloxidase, and signal-mediating molecules (inducible nitric oxide synthase. Furthermore, Gmm(Wgm- adults harbor a reduced population of sessile and circulating hemocytes, a phenomenon that likely results from a significant decrease in larval expression of serpent and lozenge, both of which are associated with the process of early hemocyte differentiation. Our results demonstrate that Wigglesworthia must be present during the development of immature progeny in order for the immune system to function properly in adult tsetse. This phenomenon provides

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.

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.

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...

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...

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)

Investigating the environmental Kuznets curve hypothesis: the role of tourism and ecological footprint.

Science.gov (United States)

Ozturk, Ilhan; Al-Mulali, Usama; Saboori, Behnaz

2016-01-01

The main objective of this study is to examine the environmental Kuznets curve (EKC) hypothesis by utilizing the ecological footprint as an environment indicator and GDP from tourism as the economic indicator. To achieve this goal, an environmental degradation model is established during the period of 1988-2008 for 144 countries. The results from the time series generalized method of moments (GMM) and the system panel GMM revealed that the number of countries that have a negative relationship between the ecological footprint and its determinants (GDP growth from tourism, energy consumption, trade openness, and urbanization) is more existent in the upper middle- and high-income countries. Moreover, the EKC hypothesis is more present in the upper middle- and high-income countries than the other income countries. From the outcome of this research, a number of policy recommendations were provided for the investigated countries.

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.

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...

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.

Quality of institution and the FEG (forest, energy intensity, and globalization) -environment relationships in sub-Saharan Africa.

Science.gov (United States)

Amuakwa-Mensah, Franklin; Adom, Philip Kofi

2017-07-01

The current share of sub-Saharan Africa in global carbon dioxide emissions is negligible compared to major contributors like Asia, Americas, and Europe. This trend is, however, likely to change given that both economic growth and rate of urbanization in the region are projected to be robust in the future. The current study contributes to the literature by examining both the direct and the indirect impacts of quality of institution on the environment. Specifically, we investigate whether the institutional setting in the region provides some sort of a complementary role in the environment-FEG relationships. We use the panel two-step system generalized method of moments (GMM) technique to deal with the simultaneity problem. Data consists of 43 sub-Saharan African countries. The result shows that energy inefficiency compromises environmental standards. However, the quality of the institutional setting helps moderate this negative consequences; countries with good institutions show greater prospects than countries with poor institutions. On the other hand, globalization of the region and increased forest size generate positive environmental outcomes in the region. Their impacts are, however, independent of the quality of institution. Afforestation programs, promotion of other clean energy types, and investment in energy efficiency, basic city infrastructure, and regulatory and institutional structures, are desirable policies to pursue to safeguard the environment.

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.

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

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

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

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

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

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.

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...

The Pruned State-Space System for Non-Linear DSGE Models: Theory and Empirical Applications

DEFF Research Database (Denmark)

Andreasen, Martin Møller; Fernández-Villaverde, Jesús; Rubio-Ramírez, Juan F.

and impulse response functions. Thus, our analysis introduces GMM estimation for DSGE models approximated up to third-order and provides the foundation for indirect inference and SMM when simulation is required. We illustrate the usefulness of our approach by estimating a New Keynesian model with habits...... and Epstein-Zin preferences by GMM when using …rst and second unconditional moments of macroeconomic and …nancial data and by SMM when using additional third and fourth unconditional moments and non-Gaussian innovations....

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...

Electrical appliance energy consumption control methods and electrical energy consumption systems

Science.gov (United States)

Donnelly, Matthew K [Kennewick, WA; Chassin, David P [Pasco, WA; Dagle, Jeffery E [Richland, WA; Kintner-Meyer, Michael [Richland, WA; Winiarski, David W [Kennewick, WA; Pratt, Robert G [Kennewick, WA; Boberly-Bartis, Anne Marie [Alexandria, VA

2006-03-07

Electrical appliance energy consumption control methods and electrical energy consumption systems are described. In one aspect, an electrical appliance energy consumption control method includes providing an electrical appliance coupled with a power distribution system, receiving electrical energy within the appliance from the power distribution system, consuming the received electrical energy using a plurality of loads of the appliance, monitoring electrical energy of the power distribution system, and adjusting an amount of consumption of the received electrical energy via one of the loads of the appliance from an initial level of consumption to an other level of consumption different than the initial level of consumption responsive to the monitoring.

Electrical appliance energy consumption control methods and electrical energy consumption systems

Science.gov (United States)

Donnelly, Matthew K [Kennewick, WA; Chassin, David P [Pasco, WA; Dagle, Jeffery E [Richland, WA; Kintner-Meyer, Michael [Richland, WA; Winiarski, David W [Kennewick, WA; Pratt, Robert G [Kennewick, WA; Boberly-Bartis, Anne Marie [Alexandria, VA

2008-09-02

Electrical appliance energy consumption control methods and electrical energy consumption systems are described. In one aspect, an electrical appliance energy consumption control method includes providing an electrical appliance coupled with a power distribution system, receiving electrical energy within the appliance from the power distribution system, consuming the received electrical energy using a plurality of loads of the appliance, monitoring electrical energy of the power distribution system, and adjusting an amount of consumption of the received electrical energy via one of the loads of the appliance from an initial level of consumption to an other level of consumption different than the initial level of consumption responsive to the monitoring.

Energy Systems Integration Newsletter - December 2016 | Energy Systems

Science.gov (United States)

system makes renewable energy integration easier. ESIF Research Shows That Connected Residential Devices and business intelligence. Baggu also noted the opportunity to harness next-generation graphical -through, ramp rate control, soft-start reconnection, and voltage-watt control. NREL then conducted power

Energy management systems in buildings

Energy Technology Data Exchange (ETDEWEB)

Lush, D. M.

1979-07-01

An investigation is made of the range of possibilities available from three types of systems (automatic control devices, building envelope, and the occupants) in buildings. The following subjects are discussed: general (buildings, design and personnel); new buildings (envelope, designers, energy and load calculations, plant design, general design parameters); existing buildings (conservation measures, general energy management, air conditioned buildings, industrial buildings); man and motivation (general, energy management and documentation, maintenance, motivation); automatic energy management systems (thermostatic controls, optimized plant start up, air conditioned and industrial buildings, building automatic systems). (MCW)

Solar Energy Systems

Science.gov (United States)

1984-01-01

Calibrated in kilowatt hours per square meter, the solar counter produced by Dodge Products, Inc. provides a numerical count of the solar energy that has accumulated on a surface. Solar energy sensing, measuring and recording devices in corporate solar cell technology developed by Lewis Research Center. Customers for their various devices include architects, engineers and others engaged in construction and operation of solar energy facilities; manufacturers of solar systems or solar related products, such as glare reducing windows; and solar energy planners in federal and state government agencies.

Design and management of energy-efficient hybrid electrical energy storage systems

CERN Document Server

Kim, Younghyun

2014-01-01

This book covers system-level design optimization and implementation of hybrid energy storage systems. The author introduces various techniques to improve the performance of hybrid energy storage systems, in the context of design optimization and automation. Various energy storage techniques are discussed, each with its own advantages and drawbacks, offering viable, hybrid approaches to building a high performance, low cost energy storage system. Novel design optimization techniques and energy-efficient operation schemes are introduced. The author also describes the technical details of an act

Energy Systems Analysis of Waste to Energy Technologies by use of EnergyPLAN

DEFF Research Database (Denmark)

Münster, Marie

Even when policies of waste prevention, re-use and recycling are prioritised, a fraction of waste will still be left which can be used for energy recovery. This report asks the question: How to utilise waste for energy in the best way seen from an energy system perspective? Eight different Waste......-to-Energy technologies are compared with a focus on fuel efficiency, CO2 reductions and costs. The comparison is made by conducting detailed energy system analyses of the present system as well as a potential future Danish energy system with a large share of combined heat and power and wind power. The study shows...... the potential of using waste for the production of transport fuels such as upgraded biogas and petrol made from syngas. Biogas and thermal gasification technologies are interesting alternatives to waste incineration and it is recommended to support the use of biogas based on manure and organic waste. It is also...

Financial overview of integrated community energy systems

Energy Technology Data Exchange (ETDEWEB)

Croke, K. G.; Hurter, A. P.; Lerner, E.; Breen, W.; Baum, J.

1977-01-01

This report is designed to analyze the commercialization potential of various concepts of community-scale energy systems that have been termed Integrated Community Energy Systems (ICES). A case analysis of alternative ICES concepts applied to a major metropolitan development complex is documented. The intent of this study is twofold: (1) to develop a framework for comparing ICES technologies to conventional energy supply systems and (2) to identify potential problems in the commercialization of new systems approaches to energy conservation. In brief, the ICES Program of the ERDA Office of Energy Conservation is intended to identify the opportunities for energy conservation in the community context through analysis, development, and/or demonstration of: location and design of buildings, building complexes, and infrastructure links; engineering and systems design of existing, emerging, and advanced energy production and delivery technologies and systems; regulatory designs for public planning, administration, and regulation of energy-conserving community development and energy services; and financial planning for energy-conserving community development and energy supply systems.

Technology Roadmap. Energy Loss Reduction and Recovery in Industrial Energy Systems

Energy Technology Data Exchange (ETDEWEB)

none,

2004-11-01

To help guide R&D decision-making and gain industry insights on the top opportunities for improved energy systems, ITP sponsored the Energy Loss Reduction and Recoveryin Energy Systems Roadmapping Workshopin April 2004 in Baltimore, Maryland. This Technology Roadmapis based largely on the results of the workshop and additional industrial energy studies supported by ITP and EERE. It summarizes industry feedback on the top opportunities for R&D investments in energy systems, and the potential for national impacts on energy use and the environment.

Energy field of thermodynamic syste'ms

International Nuclear Information System (INIS)

Volchenkova, R.A.

1984-01-01

To reveal the qualitative and quantitative rules, regulating the properties of macro- and microsystems consideration is being given to the dependence of system enthalpy on environmental conditions. It was concluded that the dependence of material system enthalpy on temperature represents the energy field, containing the energy boundaries of phase states, described by exponential functions, in which the elements are arranged monotonically in the sequence of change of interatomic bonds, correlated with their physicomechanical properties; energy boundaries of phase states at that emanate from a single point, which is a reference a single point, which a reference one for the whole material system and determining its energy state in initial position. The presented energy field of thermodynamic systems enables to consider the change of their physicomechanical properties and energy state in dynamic process, depending on environmental parameters. Energy characteristics of single-component systems (W, Re, Hf, Nb, Mo etc) are given

Integrated electrofuels and renewable energy systems

DEFF Research Database (Denmark)

Ridjan, Iva

energy into chemical energy by means of electrolysers, thus connecting fluctuating renewable energy to the vast amount of fuel storage already available in today’s energy systems. The conducted research indicates that electrofuels for heavy-duty transportation are technically and economically viable...... in energy systems and could play an important role in future energy systems. The cross-sector approach in the fuel production, by redirecting the excess electricity to the transport sector, is creating the flexibility and storage buffer for fluctuating electricity. The key concern in the short term should...

The intelligent energy system for tomorrow

Energy Technology Data Exchange (ETDEWEB)

Larsen, Hans; Morthorst, Poul Erik; Bindslev, Henrik; Sonderberg Petersen, Leif

2010-09-15

In a future energy system non-fossil fuels have taken the lead, end-use technologies are highly efficient and closely interlinked to supply through intelligent energy systems. Climate change issues, security of supply and economic development need to be pursued concurrently. This calls for flexible and intelligent energy system infrastructures that effectively accommodate large amounts of fluctuating renewable energy and let the end-user interact with the supply through advanced ICT. The second important characteristic is intelligent integration of the entire transport sector. The third key area is advanced energy storage facilities in the system and the introduction of super-grids.

Energy efficiency system development

Science.gov (United States)

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

2017-09-01

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

Solar Energy Grid Integration Systems -- Energy Storage (SEGIS-ES).

Energy Technology Data Exchange (ETDEWEB)

Hanley, Charles J.; Ton, Dan T. (U.S. Department of Energy, Washington, D.C.); Boyes, John D.; Peek, Georgianne Huff

2008-07-01

This paper describes the concept for augmenting the SEGIS Program (an industry-led effort to greatly enhance the utility of distributed PV systems) with energy storage in residential and small commercial applications (SEGIS-ES). The goal of SEGIS-ES is to develop electrical energy storage components and systems specifically designed and optimized for grid-tied PV applications. This report describes the scope of the proposed SEGIS-ES Program and why it will be necessary to integrate energy storage with PV systems as PV-generated energy becomes more prevalent on the nation's utility grid. It also discusses the applications for which energy storage is most suited and for which it will provide the greatest economic and operational benefits to customers and utilities. Included is a detailed summary of the various storage technologies available, comparisons of their relative costs and development status, and a summary of key R&D needs for PV-storage systems. The report concludes with highlights of areas where further PV-specific R&D is needed and offers recommendations about how to proceed with their development.

Event-related stresses in energy systems and their effects on energy security

International Nuclear Information System (INIS)

Hughes, Larry; Ranjan, Ashish

2013-01-01

Energy systems change over time as events, such as grid failures, new energy sources, and extreme weather conditions, occur, often affecting the system's energy security. Understanding events, their causes, and how they are handled, can help a jurisdiction and its energy stakeholders develop better, evidence-based energy policy. This paper employs a definition of stress in combination with systems analysis to specify methods for explaining the states through which an energy process, chain, or system passes in response to an event and how this response results in energy security improving, deteriorating, or being maintained. The definition uses three dimensions-availability, affordability, and acceptability-derived from the International Energy Agency's definition of energy security to show when and how a system's energy security will change. Examples are used to illustrate the application of the methods. - Highlights: • A generic set of methods and a common terminology to formalize the ongoing energy security discourse is proposed. • The methods define, measure and explain how energy security can change when events cause stresses in an energy system. • Events are classified in terms of three dimensions derived from the IEA's definition of energy security. • The application of the method is illustrated with detailed examples

Small Wind Energy Systems

DEFF Research Database (Denmark)

Simoes, Marcelo; Farret, Felix Alberto; Blaabjerg, Frede

2015-01-01

devices, and a centralized distribution control. In order to establish a small wind energy system it is important to observe the following: (i) Attending the energy requirements of the actual or future consumers; (ii) Establishing civil liabilities in case of accidents and financial losses due to shortage...... or low quality of energy; (iii) Negotiating collective conditions to interconnect the microgrid with the public network or with other sources of energy that is independent of wind resources; (iv) Establishing a performance criteria of power quality and reliability to end-users, in order to reduce costs...... and guaranteeing an acceptable energy supply. This paper discuss how performance is affected by local conditions and random nature of the wind, power demand profiles, turbine related factors, and presents the technical issues for implementing a self-excited induction generator system, or a permanent magnet based...

A Sustainable Energy System in Latvia

DEFF Research Database (Denmark)

Rasmussen, Lotte Holmberg

2002-01-01

This paper presents some of the problems in the Latvian energy system, the Latvian economy and how a sustainable restructuring of the energy system with renewable energy, co-generation and the production of energy technology can help solve some of the problems....

Integrated roof wind energy system

Directory of Open Access Journals (Sweden)

Moonen S.P.G.

2012-10-01

Full Text Available Wind is an attractive renewable source of energy. Recent innovations in research and design have reduced to a few alternatives with limited impact on residential construction. Cost effective solutions have been found at larger scale, but storage and delivery of energy to the actual location it is used, remain a critical issue. The Integrated Roof Wind Energy System is designed to overcome the current issues of urban and larger scale renewable energy system. The system is built up by an axial array of skewed shaped funnels that make use of the Venturi Effect to accelerate the wind flow. This inventive use of shape and geometry leads to a converging air capturing inlet to create high wind mass flow and velocity toward a vertical-axis wind turbine in the top of the roof for generation of a relatively high amount of energy. The methods used in this overview of studies include an array of tools from analytical modelling, PIV wind tunnel testing, and CFD simulation studies. The results define the main design parameters for an efficient system, and show the potential for the generation of high amounts of renewable energy with a novel and effective system suited for the built environment.

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).

Career Directions--Renewable Energy Systems Integrator

Science.gov (United States)

Fleeman, Stephen R.

2012-01-01

Renewable energy systems are beginning to appear everywhere. Solar modules are creating "blue roofs" that convert the energy from the sun into household electricity. Solar thermal systems on roofs can generate hot water. Wind turbines catch breezes to provide even more electricity. Recommendations for saving energy, specifying systems for…

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

Science.gov (United States)

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

2016-09-13

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

Understanding renewable energy systems

Energy Technology Data Exchange (ETDEWEB)

Quaschning, Volker

2005-01-15

Beginning with an overview of renewable energy sources including biomass, hydroelectricity, geothermal, tidal, wind and solar power, this book explores the fundamentals of different renewable energy systems. The main focus is on technologies with high development potential such as solar thermal systems, photovoltaics and wind power. This text not only describes technological aspects, but also deals consciously with problems of the energy industry. In this way, the topics are treated in a holistic manner, bringing together maths, engineering, climate studies and economics, and enabling readers to gain a broad understanding of renewable energy technologies and their potential. The book also contains a free CD-ROM resource, which includes a variety of specialist simulation software and detailed figures from the book. (Author)

Energy information systems: a general overview

International Nuclear Information System (INIS)

Sen, B.K.

1991-01-01

The unprecedented energy crises that engulfed the world in early 1970s brought about a spurt in energy research all over the world, which in turn caused the rapid growth of literature in the field. In order to achieve effective bibliographical control, proper dissemination of information, and rapid access to the desired document, energy information systems of diverse scope came into being. The paper describes the special features of several information systems like (i) International Nuclear Information Systems, which covers world literature on nuclear science and technology (ii) Energy Information Services which takes cares of energy information transfer among the Commonwealth countries of the Asia and Pacific region; (ii) Information Network on New Energy Sources and Technologies for Asia And Pacific. This system is being developed to ensure smooth energy information transfer amongst non-commonwealth countries of Asia and the Pacific. (author)

Potential Evaluation of Energy Supply System in Grid Power System, Commercial, and Residential Sectors by Minimizing Energy Cost

Science.gov (United States)

Oda, Takuya; Akisawa, Atushi; Kashiwagi, Takao

If the economic activity in the commercial and residential sector continues to grow, improvement in energy conversion efficiencies of energy supply systems is necessary for CO2 mitigation. In recent years, the electricity driven hot water heat pump (EDHP) and the solar photo voltaic (PV) are commercialized. The fuel cell (FC) of co-generation system (CGS) for the commercial and residential sector will be commercialized in the future. The aim is to indicate the ideal energy supply system of the users sector, which both manages the economical cost and CO2 mitigation, considering the grid power system. In the paper, cooperative Japanese energy supply systems are modeled by linear-programming. It includes the grid power system and energy systems of five commercial sectors and a residential sector. The demands of sectors are given by the objective term for 2005 to 2025. 24 hours load for each 3 annual seasons are considered. The energy systems are simulated to be minimize the total cost of energy supply, and to be mitigate the CO2 discharge. As result, the ideal energy system at 2025 is shown. The CGS capacity grows to 30% (62GW) of total power system, and the EDHP capacity is 26GW, in commercial and residential sectors.

Electrical energy systems

CERN Document Server

El-Hawary, Mohamed E

2007-01-01

Features discussions ranging from the technical aspects of generation, transmission, distribution, and utilization to power system components, theory, protection, and the energy control center that offer an introduction to effects of deregulating electric power systems, blackouts and their causes, and minimizing their effects.

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

CO2 emissions, energy consumption and economic growth nexus in MENA countries: Evidence from simultaneous equations models

International Nuclear Information System (INIS)

Omri, Anis

2013-01-01

This paper examines the nexus between CO 2 emissions, energy consumption and economic growth using simultaneous-equations models with panel data of 14 MENA countries over the period 1990–2011. Our empirical results show that there exists a bidirectional causal relationship between energy consumption and economic growth. However, the results support the occurrence of unidirectional causality from energy consumption to CO 2 emissions without any feedback effects, and there exists a bidirectional causal relationship between economic growth and CO 2 emissions for the region as a whole. The study suggests that environmental and energy policies should recognize the differences in the nexus between energy consumption and economic growth in order to maintain sustainable economic growth in the MENA region. - Graphical abstract: Interaction between CO 2 , energy and GDP for MENA countries. - Highlights: • We investigate the energy–environment–GDP nexus for 14 MENA countries. • We have used simultaneous equations models estimated by the GMM-estimator. • Results show bi-directional causal relationship between energy consumption and economic growth. • There is uni-directional causality from energy consumption to CO 2 . • There exists bi-directional causal relationship between economic growth and pollutant emissions

HYDROKINETIC ENERGY CONVERSION SYSTEMS: PROSPECTS ...

African Journals Online (AJOL)

eobe

Hydrokinetic energy conversion systems utilize the kinetic energy of flowing water bodies with little or no head to generate ... generator. ... Its principle of operation is analogous to that of wind ..... Crisis-solar and wind power systems, 2009,.

Energy Systems Modelling Research and Analysis

DEFF Research Database (Denmark)

Møller Andersen, Frits; Alberg Østergaard, Poul

2015-01-01

This editorial introduces the seventh volume of the International Journal of Sustainable Energy Planning and Management. The volume presents part of the outcome of the project Energy Systems Modelling Research and Analysis (ENSYMORA) funded by the Danish Innovation Fund. The project carried out b...... by 11 university and industry partners has improved the basis for decision-making within energy planning and energy scenario making by providing new and improved tools and methods for energy systems analyses.......This editorial introduces the seventh volume of the International Journal of Sustainable Energy Planning and Management. The volume presents part of the outcome of the project Energy Systems Modelling Research and Analysis (ENSYMORA) funded by the Danish Innovation Fund. The project carried out...

Energy Management of Smart Distribution Systems

Science.gov (United States)

Ansari, Bananeh

Electric power distribution systems interface the end-users of electricity with the power grid. Traditional distribution systems are operated in a centralized fashion with the distribution system owner or operator being the only decision maker. The management and control architecture of distribution systems needs to gradually transform to accommodate the emerging smart grid technologies, distributed energy resources, and active electricity end-users or prosumers. The content of this document concerns with developing multi-task multi-objective energy management schemes for: 1) commercial/large residential prosumers, and 2) distribution system operator of a smart distribution system. The first part of this document describes a method of distributed energy management of multiple commercial/ large residential prosumers. These prosumers not only consume electricity, but also generate electricity using their roof-top solar photovoltaics systems. When photovoltaics generation is larger than local consumption, excess electricity will be fed into the distribution system, creating a voltage rise along the feeder. Distribution system operator cannot tolerate a significant voltage rise. ES can help the prosumers manage their electricity exchanges with the distribution system such that minimal voltage fluctuation occurs. The proposed distributed energy management scheme sizes and schedules each prosumer's ES to reduce the electricity bill and mitigate voltage rise along the feeder. The second part of this document focuses on emergency energy management and resilience assessment of a distribution system. The developed emergency energy management system uses available resources and redundancy to restore the distribution system's functionality fully or partially. The success of the restoration maneuver depends on how resilient the distribution system is. Engineering resilience terminology is used to evaluate the resilience of distribution system. The proposed emergency energy

Potential of renewable energy systems in China

DEFF Research Database (Denmark)

Liu, Wen; Lund, Henrik; Mathiesen, Brian Vad

2011-01-01

Along with high-speed economic development and increasing energy consumption, the Chinese Government faces a growing pressure to maintain the balance between energy supply and demand. In 2009, China has become both the largest energy consumer and CO2 emitting country in the world. In this case...... system has demonstrated the possibility of converting into a 100% renewable energy system. This paper discusses the perspective of renewable energy in China firstly, and then analyses whether it is suitable to adopt similar methodologies applied in other countries as China approaches a renewable energy...... system. The conclusion is that China’s domestic renewable energy sources are abundant and show the possibility to cover future energy demand; the methodologies used to analyse a 100% renewable energy system are applicable in China. Therefore, proposing an analysis of a 100% renewable energy system...

High-Energy Beam Transport system

International Nuclear Information System (INIS)

Melson, K.E.; Farrell, J.A.; Liska, D.J.

1979-01-01

The High-Energy Beam Transport (HEBT) system for the Fusion Materials Irradiation Test (FMIT) Facility is to be installed at the Hanford Engineering Development Laboratory (HEDL) at Richland, Washington. The linear accelerator must transport a large emittance, high-current, high-power, continuous-duty deuteron beam with a large energy spread either to a lithium target or a beam stop. A periodic quadrupole and bending-magnet system provides the beam transport and focusing on target with small beam aberrations. A special rf cavity distributes the energy in the beam so that the Bragg Peak is distributed within the lithium target. Operation of the rf control system, the Energy Dispersion Cavity (EDC), and the beam transport magnets is tested on the beam stop during accelerator turn-on. Characterizing the beam will require extensions of beam diagnostic techniques and noninterceptive sensors. Provisions are being made in the facility for suspending the transport system from overhead supports using a cluster system to simplify maintenance and alignment techniques

Integration of renewable and conventional energies. How to design future energy systems?

Energy Technology Data Exchange (ETDEWEB)

Hellinger, Rolf [Siemens AG, Erlangen (Germany). CT RTC PET

2015-07-01

The worldwide increasing energy demand, especially in the economically emerging countries, and the climate change are a major challenge for the energy supply. One of the most severe challenges is the reduction of carbon dioxide emissions which can also be seen in the planned investment for energy systems. At the same time, energy systems worldwide are in transition, driven by market and technology trends. As a consequence of these trends, the complexity of future energy systems will extremely increase. The paper outlines a new approach for sustainable, reliable and affordable energy systems of the future, based on technologies, available and under development, which combine different forms of energy.

Integration of renewable and conventional energies. How to design future energy systems?

International Nuclear Information System (INIS)

Hellinger, Rolf

2015-01-01

The worldwide increasing energy demand, especially in the economically emerging countries, and the climate change are a major challenge for the energy supply. One of the most severe challenges is the reduction of carbon dioxide emissions which can also be seen in the planned investment for energy systems. At the same time, energy systems worldwide are in transition, driven by market and technology trends. As a consequence of these trends, the complexity of future energy systems will extremely increase. The paper outlines a new approach for sustainable, reliable and affordable energy systems of the future, based on technologies, available and under development, which combine different forms of energy.

Innovative nuclear energy systems roadmap

International Nuclear Information System (INIS)

2007-12-01

Developing nuclear energy that is sustainable, safe, has little waste by-product, and cannot be proliferated is an extremely vital and pressing issue. To resolve the four issues through free thinking and overall vision, research activities of 'innovative nuclear energy systems' and 'innovative separation and transmutation' started as a unique 21st Century COE Program for nuclear energy called the Innovative Nuclear Energy Systems for Sustainable Development of the World, COE-INES. 'Innovative nuclear energy systems' include research on CANDLE burn-up reactors, lead-cooled fast reactors and using nuclear energy in heat energy. 'Innovative separation and transmutation' include research on using chemical microchips to efficiently separate TRU waste to MA, burning or destroying waste products, or transmuting plutonium and other nuclear materials. Research on 'nuclear technology and society' and 'education' was also added in order for nuclear energy to be accepted into society. COE-INES was a five-year program ending in 2007. But some activities should be continued and this roadmap detailed them as a rough guide focusing inventions and discoveries. This technology roadmap was created for social acceptance and should be flexible to respond to changing times and conditions. (T. Tanaka)

Principles of sustainable energy systems

CERN Document Server

Kreith, Frank

2013-01-01

… ""This is an ideal book for seniors and graduate students interested in learning about the sustainable energy field and its penetration. The authors provide very strong discussion on cost-benefit analysis and ROI calculations for various alternate energy systems in current use. This is a descriptive book with detailed case-based analyses of various systems and engineering applications. The text book provides real-world case studies and related problems pertaining to sustainable energy systems.""--Dr. Kuruvilla John, University of North Texas""The new edition of ""Principles of Sustainable En

Risoe energy report 4: The future energy system - distributed production and use

International Nuclear Information System (INIS)

Larsen, Hans; Soenderberg Petersen, L.

2005-10-01

The world is facing major challenges in providing energy services to meet the future needs of the developed world and the growing needs of developing countries. These challenges are exacerbated by the need to provide energy services with due respect to economic growth, sustainability and security of supply. Today, the world's energy system is based mainly on oil, gas and coal, which together supply around 80% of our primary energy. Only around 0.5% of primary energy comes from renewable sources such as wind, solar and geothermal. Despite the rapid development of new energy technologies, the world will continue to depend on fossil fuels for several decades to come - and global primary energy demand is forecasted to grow by 60% between 2002 and 2030. The expected post Kyoto targets call for significant CO 2 reductions, increasing the demand to decouple the energy and transport systems from fossil fuels. There is a strong need for closer links between electricity, heat and other energy carriers, including links to the transport sector. On a national scale Denmark has three main characteristics. Firstly, it has a diverse and distributed energy system based on the power grid, the district heating grid and the natural gas grid. Secondly, renewable energy, especially wind power, plays an increasingly important role in the Danish energy system. Thirdly, Denmark's geographical location allows it to act as a buffer between the energy systems of the European continent and the Nordic countries. Energy systems can be made more robust by decentralising both power generation and control. Distributed generation (DG) is characterised by a variety of energy production technologies integrated into the electricity supply system, and the ability of different segments of the grid to operate autonomously. The use of a more distributed power generation system would be an important element in the protection of the consumers against power interruptions and blackouts, whether caused by

Hydrogen based energy storage for solar energy systems

Energy Technology Data Exchange (ETDEWEB)

Vanhanen, J.P.; Hagstroem, M.T.; Lund, P.H. [Helsinki Univ. of Technology, Otaniemi (Finland). Dept. of Engineering Physics and Mathematics; Leppaenen, J.R.; Nieminen, J.P. [Neste Oy (Finland)

1998-12-31

Hydrogen based energy storage options for solar energy systems was studied in order to improve their overall performance. A 1 kW photovoltaic hydrogen (PV-H2) pilot-plant and commercial prototype were constructed and a numerical simulation program H2PHOTO for system design and optimisation was developed. Furthermore, a comprehensive understanding of conversion (electrolysers and fuel cells) and storage (metal hydrides) technologies was acquired by the project partners. The PV-H{sub 2} power system provides a self-sufficient solution for applications in remote locations far from electric grids and maintenance services. (orig.)

Energy Flexibility in the Power System

DEFF Research Database (Denmark)

Billanes, Joy Dalmacio; Ma, Zheng; Jørgensen, Bo Nørregaard

2017-01-01

Energy flexibility can address the challenges of large scale integration of renewable energy resources and thereby increasing imbalance in the power system. Flexible power system can provide reliable supply, low electricity cost and sustainability. Various situations and factors influence...... the adoption of the flexibility solutions, such as flexible electricity generation, demand-response, and electricity storage. This paper tries to analyze the current energy flexibility solutions and the factors that can influence the energy flexibility adoption. This paper takes Philippines as case study...... to provide an overview of the current condition of the Philippines’ power system and discuss the energy flexibility in the Philippines’ power system. A further discussion and recommendation is conducted in the end of the paper....

Diversification and localization of energy systems for sustainable development and energy security

International Nuclear Information System (INIS)

Xianguo Li

2005-01-01

The dominance of a single-energy system inevitably leads to excessive burden on, and eventually weakening, a particular aspect of the environment, and can cause environmental fatigue and failure (permanent damage) or even catastrophe if dominated for too long; thus it inevitably poses the health and environmental risk. This is the case for our currently fossil-fuel-based energy systems. In fact, each energy system, including renewables and alternative fuels, has its own unique adverse impact on the environment, as dictated by the second law of thermodynamics. A truly sustainable development may be achieved with the diversification and localization of energy sources and systems if the adverse impact of each energy system is sufficiently small and well within the tolerance limit of the environment. Energy diversification and localization would also provide a security for the energy supply and distribution as well for the energy consumers - a specifically important issue in the wake of blackout (electric power failure) in the Northeastern states to the Midwest of the United States and part of Canada on August 14, 2003. The idea of diversified energy systems for the good of humanity and environment is similar to many analogies in other fields, such as bio-diversity is the best means to prevent the spread and damage of diseases and pests, and diversified investment is the best strategy to guarantee the overall best investment return. It is concluded that the diversification and localization of energy systems is the best future energy systems that would be environmentally compatible, and allow for sustainable development as well as energy security for both supply and distribution to the energy consumers. (Author)

Diversification and localization of energy systems for sustainable development and energy security

International Nuclear Information System (INIS)

Li Xianguo

2005-01-01

The dominance of a single-energy system inevitably leads to excessive burden on, and eventually weakening, a particular aspect of the environment, and can cause environmental fatigue and failure (permanent damage) or even catastrophe if dominated for too long; thus it inevitably poses the health and environmental risk. This is the case for our currently fossil-fuel-based energy systems. In fact, each energy system, including renewables and alternative fuels, has its own unique adverse impact on the environment, as dictated by the second law of thermodynamics. A truly sustainable development may be achieved with the diversification and localization of energy sources and systems if the adverse impact of each energy system is sufficiently small and well within the tolerance limit of the environment. Energy diversification and localization would also provide a security for the energy supply and distribution as well for the energy consumers - a specifically important issue in the wake of blackout (electric power failure) in the Northeastern states to the Midwest of the United States and part of Canada on August 14, 2003. The idea of diversified energy systems for the good of humanity and environment is similar to many analogies in other fields, such as bio-diversity is the best means to prevent the spread and damage of diseases and pests, and diversified investment is the best strategy to guarantee the overall best investment return. It is concluded that the diversification and localization of energy systems is the best future energy systems that would be environmentally compatible, and allow for sustainable development as well as energy security for both supply and distribution to the energy consumers

Potential of renewable energy systems in China

International Nuclear Information System (INIS)

Liu, Wen; Lund, Henrik; Mathiesen, Brian Vad; Zhang, Xiliang

2011-01-01

Along with high-speed economic development and increasing energy consumption, the Chinese Government faces a growing pressure to maintain the balance between energy supply and demand. In 2009, China has become both the largest energy consumer and CO 2 emitting country in the world. In this case, the inappropriate energy consumption structure should be changed. As an alternative, a suitable infrastructure for the implementation of renewable energy may serve as a long-term sustainable solution. The perspective of a 100% renewable energy system has been analyzed and discussed in some countries previously. In this process, assessment of domestic renewable energy sources is the first step. Then appropriate methodologies are needed to perform energy system analyses involving the integration of more sustainable strategies. Denmark may serve as an example of how sustainable strategies can be implemented. The Danish system has demonstrated the possibility of converting into a 100% renewable energy system. This paper discusses the perspective of renewable energy in China firstly, and then analyses whether it is suitable to adopt similar methodologies applied in other countries as China approaches a renewable energy system. The conclusion is that China's domestic renewable energy sources are abundant and show the possibility to cover future energy demand; the methodologies used to analyse a 100% renewable energy system are applicable in China. Therefore, proposing an analysis of a 100% renewable energy system in China is not unreasonable. (author)

Flow energy conversion system

International Nuclear Information System (INIS)

Sargsyan, R.A.

2011-01-01

A cost-effective hydropower system called here Flow Energy Converter was developed, patented, manufactured and tested for water pumping, electricity generation and other purposes especially useful for the rural communities. The system consists of water-driven turbine with plane-surface blades, power transmission means and pump and/or generator. Working sample of the Flow Energy Converter was designed and manufactured at the Institute of Radio Physics and Electronics

Programming models for energy-aware systems

Science.gov (United States)

Zhu, Haitao

Energy efficiency is an important goal of modern computing, with direct impact on system operational cost, reliability, usability and environmental sustainability. This dissertation describes the design and implementation of two innovative programming languages for constructing energy-aware systems. First, it introduces ET, a strongly typed programming language to promote and facilitate energy-aware programming, with a novel type system design called Energy Types. Energy Types is built upon a key insight into today's energy-efficient systems and applications: despite the popular perception that energy and power can only be described in joules and watts, real-world energy management is often based on discrete phases and modes, which in turn can be reasoned about by type systems very effectively. A phase characterizes a distinct pattern of program workload, and a mode represents an energy state the program is expected to execute in. Energy Types is designed to reason about energy phases and energy modes, bringing programmers into the optimization of energy management. Second, the dissertation develops Eco, an energy-aware programming language centering around sustainability. A sustainable program built from Eco is able to adaptively adjusts its own behaviors to stay on a given energy budget, avoiding both deficit that would lead to battery drain or CPU overheating, and surplus that could have been used to improve the quality of the program output. Sustainability is viewed as a form of supply and demand matching, and a sustainable program consistently maintains the equilibrium between supply and demand. ET is implemented as a prototyped compiler for smartphone programming on Android, and Eco is implemented as a minimal extension to Java. Programming practices and benchmarking experiments in these two new languages showed that ET can lead to significant energy savings for Android Apps and Eco can efficiently promote battery awareness and temperature awareness in real

Localism and energy: Negotiating approaches to embedding resilience in energy systems

International Nuclear Information System (INIS)

O'Brien, Geoff; Hope, Alex

2010-01-01

Tensions are evident in energy policy objectives between centralised top-down interconnected energy systems and localised distributed approaches. Examination of these tensions indicates that a localised approach can address a systemic problem of interconnected systems; namely vulnerability. The challenge for energy policy is to realise the interrelated goals of energy security, climate and environmental targets and social and economic issues such as fuel poverty, whilst mitigating vulnerability. The effectiveness of conventional approaches is debatable. A transition to a low carbon pathway should focus on resilience, counter to vulnerability. This article draws from on-going work which evaluates the energy aspects of a Private Finance Initiative (PFI) project to refurbish and re-build a local authority's entire stock of sheltered accommodation to high environmental standards. Initial findings suggest that whereas more conventional procurement processes tend to increase systemic vulnerability, a user focussed process driven through PFI competitive dialogue is beginning to motivate some developers to adopt innovative approaches to energy system development.

Energy storage connection system

Science.gov (United States)

Benedict, Eric L.; Borland, Nicholas P.; Dale, Magdelena; Freeman, Belvin; Kite, Kim A.; Petter, Jeffrey K.; Taylor, Brendan F.

2012-07-03

A power system for connecting a variable voltage power source, such as a power controller, with a plurality of energy storage devices, at least two of which have a different initial voltage than the output voltage of the variable voltage power source. The power system includes a controller that increases the output voltage of the variable voltage power source. When such output voltage is substantially equal to the initial voltage of a first one of the energy storage devices, the controller sends a signal that causes a switch to connect the variable voltage power source with the first one of the energy storage devices. The controller then causes the output voltage of the variable voltage power source to continue increasing. When the output voltage is substantially equal to the initial voltage of a second one of the energy storage devices, the controller sends a signal that causes a switch to connect the variable voltage power source with the second one of the energy storage devices.

Energy Management Systems to Reduce Electrical Energy Consumption

OpenAIRE

Oriti, Giovanna

2015-01-01

EXECUTIVE SUMMARY An energy management system comprises an electrical energy storage element such as a battery, renewable electrical energy sources such as solar and wind, a digital signal processing controller and a solid state power converter to interface the elements together. This hardware demonstration in the lab at the Naval Postgraduate School will focus on solid state power conversion methods to improve the reliability and efficiency of electrical energy consumption by Navy facilit...

Energy system impacts of desalination in Jordan

Directory of Open Access Journals (Sweden)

Poul Alberg Østergaard

2014-02-01

Full Text Available Climate change mitigation calls for energy systems minimising end-use demands, optimising the fuel efficiency of conversion systems, increasing the use of renewable energy sources and exploiting synergies wherever possible. In parallel, global fresh water resources are strained due to amongst others population and wealth increase and competitive water uses from agriculture and industry is causing many nations to turn to desalination technologies. This article investigates a Jordanian energy scenario with two different desalination technologies; reverse osmosis (RO driven by electricity and Multi Stage Flash (MSF desalination driven by Cogeneration of Heat and Power (CHP. The two systems impact the energy systems in different ways due to the technologies’ particular characteristics. The systems are analyses in the energy systems analysis model EnergyPLAN to determine the impacts on energy system performance. Results indicate that RO and MSF are similar in fuel use. While there is no use of waste heat from condensing mode plants, efficiencies for CHP and MSF are not sufficiently good to results in lower fuel usage than RO. The Jordanian energy system is somewhat inflexible giving cause to Critical Excess Electricity Production (CEEP even at relatively modest wind power penetrations. Here RO assists the energy system in decreasing CEEP – and even more if water storage is applied.

World energy data system (WENDS)

International Nuclear Information System (INIS)

Lareau, W.E.

1979-01-01

This paper presents a unique application of System 2000: the storage of preformatted textual information in a completely user oriented data base. The World Energy Data System is an information system which allows qualified users online access to non-classified management level data on worldwide energy technology and research and development activities. WENDS has been used to transmit up-to-date informaion on foreign energy technology and research and development programs to DOE program divisions, the Congress, and other U.S. government officials going abroad. The WENDS concept is first described. Then, the method of storage of the textual information is discussed followed by a discussion of the retrieval system which is thoroughly designed to serve the user

Energy-efficient fault-tolerant systems

CERN Document Server

Mathew, Jimson; Pradhan, Dhiraj K

2013-01-01

This book describes the state-of-the-art in energy efficient, fault-tolerant embedded systems. It covers the entire product lifecycle of electronic systems design, analysis and testing and includes discussion of both circuit and system-level approaches. Readers will be enabled to meet the conflicting design objectives of energy efficiency and fault-tolerance for reliability, given the up-to-date techniques presented.

Towards low carbon business park energy systems: Classification of techno-economic energy models

International Nuclear Information System (INIS)

Timmerman, Jonas; Vandevelde, Lieven; Van Eetvelde, Greet

2014-01-01

To mitigate climate destabilisation, human-induced greenhouse gas emissions urgently need to be curbed. A major share of these emissions originates from the industry and energy sectors. Hence, a low carbon shift in industrial and business park energy systems is called for. Low carbon business parks minimise energy-related carbon dioxide emissions by maximal exploitation of local renewable energy production, enhanced energy efficiency, and inter-firm heat exchange, combined in a collective energy system. The holistic approach of techno-economic energy models facilitates the design of such systems, while yielding an optimal trade-off between energetic, economic and environmental performances. However, no models custom-tailored for industrial park energy systems are detected in literature. In this paper, existing energy model classifications are scanned for adequate model characteristics and accordingly, a confined number of models are selected and described. Subsequently, a practical typology is proposed, existing of energy system evolution, optimisation, simulation, accounting and integration models, and key model features are compared. Finally, important features for a business park energy model are identified. - Highlights: • A holistic perspective on (low carbon) business park energy systems is introduced. • A new categorisation of techno-economic energy models is proposed. • Model characteristics are described per model category. • Essential model features for business park energy system modelling are identified. • A strategy towards a techno-economic energy model for business parks is proposed

Solar/electric heating systems for the future energy system

Energy Technology Data Exchange (ETDEWEB)

Furbo, S.; Dannemand, M.; Perers, B. [and others

2013-05-15

The aim of the project is to elucidate how individual heating units for single family houses are best designed in order to fit into the future energy system. The units are based on solar energy, electrical heating elements/heat pump, advanced heat storage tanks and advanced control systems. Heat is produced by solar collectors in sunny periods and by electrical heating elements/heat pump. The electrical heating elements/heat pump will be in operation in periods where the heat demand cannot be covered by solar energy. The aim is to use the auxiliary heating units when the electricity price is low, e.g. due to large electricity production by wind turbines. The unit is equipped with an advanced control system where the control of the auxiliary heating is based on forecasts of the electricity price, the heat demand and the solar energy production. Consequently, the control is based on weather forecasts. Three differently designed heating units are tested in a laboratory test facility. The systems are compared on the basis of: 1) energy consumption for the auxiliary heating; 2) energy cost for the auxiliary heating; 3) net utilized solar energy. Starting from a normal house a solar combi system (for hot water and house heating) can save 20-30% energy cost, alone, depending on sizing of collector area and storage volume. By replacing the heat storage with a smart tank based on electric heating elements and a smart control based on weather/load forecast and electricity price information 24 hours ahead, another 30-40% can be saved. That is: A solar heating system with a solar collector area of about 10 m{sup 2}, a smart tank based on electric heating element and a smart control system, can reduce the energy costs of the house by at least 50%. No increase of heat storage volume is needed to utilize the smart control. The savings in % are similar for different levels of building insulation. As expected a heat pump in the system can further reduce the auxiliary electricity

Risoe energy report 4: The future energy system - distributed production and use

Energy Technology Data Exchange (ETDEWEB)

Larsen, Hans; Soenderberg Petersen, L.

2005-10-01

The world is facing major challenges in providing energy services to meet the future needs of the developed world and the growing needs of developing countries. These challenges are exacerbated by the need to provide energy services with due respect to economic growth, sustainability and security of supply. Today, the world's energy system is based mainly on oil, gas and coal, which together supply around 80% of our primary energy. Only around 0.5% of primary energy comes from renewable sources such as wind, solar and geothermal. Despite the rapid development of new energy technologies, the world will continue to depend on fossil fuels for several decades to come - and global primary energy demand is forecasted to grow by 60% between 2002 and 2030. The expected post Kyoto targets call for significant CO{sub 2} reductions, increasing the demand to decouple the energy and transport systems from fossil fuels. There is a strong need for closer links between electricity, heat and other energy carriers, including links to the transport sector. On a national scale Denmark has three main characteristics. Firstly, it has a diverse and distributed energy system based on the power grid, the district heating grid and the natural gas grid. Secondly, renewable energy, especially wind power, plays an increasingly important role in the Danish energy system. Thirdly, Denmark's geographical location allows it to act as a buffer between the energy systems of the European continent and the Nordic countries. Energy systems can be made more robust by decentralising both power generation and control. Distributed generation (DG) is characterised by a variety of energy production technologies integrated into the electricity supply system, and the ability of different segments of the grid to operate autonomously. The use of a more distributed power generation system would be an important element in the protection of the consumers against power interruptions and blackouts, whether

Energy efficient residential house wall system

International Nuclear Information System (INIS)

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

2013-01-01

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

Power Electronics for Renewable Energy Systems

DEFF Research Database (Denmark)

Choi, U. M.; Lee, K. B.; Blaabjerg, Frede

2012-01-01

The use of renewable energy sources are increased because of the depletion of natural resources and the increasing pollution level from energy production. The wind energy and the solar energy are most widely used among the renewable energy sources. Power electronics is needed in almost all kinds...... of renewable energy system. It controls the renewable source and interfaces with the load effectively, which can be grid-connected or van work in stand-alone mode. In this presentation, overview of wind and photovoltaic energy systems are introduced. Next, the power electronic circuits behind the most common...

National Energy Outlook Modelling System

Energy Technology Data Exchange (ETDEWEB)

Volkers, C.M. [ECN Policy Studies, Petten (Netherlands)

2013-12-15

For over 20 years, the Energy research Centre of the Netherlands (ECN) has been developing the National Energy Outlook Modelling System (NEOMS) for Energy projections and policy evaluations. NEOMS enables 12 energy models of ECN to exchange data and produce consistent and detailed results.

Life-cycle analysis of renewable energy systems

DEFF Research Database (Denmark)

Sørensen, Bent

1994-01-01

An imlementation of life-cycle analysis (LCA) for energy systems is presented and applied to two renewable energy systems (wind turbines and building-integrated photovoltaic modules) and compared with coal plants......An imlementation of life-cycle analysis (LCA) for energy systems is presented and applied to two renewable energy systems (wind turbines and building-integrated photovoltaic modules) and compared with coal plants...

Energy system impacts of desalination in Jordan

DEFF Research Database (Denmark)

Østergaard, Poul Alberg; Lund, Henrik; Mathiesen, Brian Vad

2014-01-01

and Multi Stage Flash (MSF) desalination driven by Cogeneration of Heat and Power (CHP). The two systems impact the energy systems in different ways due to the technologies’ particular characteristics. The systems are analyses in the energy systems analysis model EnergyPLAN to determine the impacts......Climate change mitigation calls for energy systems minimising end-use demands, optimising the fuel efficiency of conversion systems, increasing the use of renewable energy sources and exploiting synergies wherever possible. In parallel, global fresh water resources are strained due to amongst...... others population and wealth increase and competitive water uses from agriculture and industry is causing many nations to turn to desalination technologies. This article investigates a Jordanian energy scenario with two different desalination technologies; reverse osmosis (RO) driven by electricity...

The role of nuclear energy system for Korean long-term energy supply strategy

International Nuclear Information System (INIS)

Chae, K.N.; Lee, D.G.; Lim, C.Y.; Lee, B.W.

1995-01-01

The energy supply optimization model MESSAGE-III is improved to evaluate the role of nuclear energy system in Korean long-term energy supply strategy. Emphasis is placed on the potential contribution of nuclear energy in case of environmental constraints and energy resource limitation. The time horizon is 1993-2040. A program to forecast useful energy demand is developed, and optimization is performed from the overall energy system to the nuclear energy system. Reactor and fuel cycle strategy and the expanded utilization options for nuclear energy system are suggested. FBRs, HTGRs and thorium fuel cycle would play key roles in the long run. The most important factors for nuclear energy in Korean energy supply strategy would be the availability of fossil fuels, CO 2 reduction regulation, and the supply capability of nuclear energy. (author)

Cluster-Based Adaptation Using Density Forest for HMM Phone Recognition

DEFF Research Database (Denmark)

Abou-Zleikha, Mohamed; Tan, Zheng-Hua; Christensen, Mads Græsbøll

2014-01-01

The dissimilarity between the training and test data in speech recognition systems is known to have a considerable effect on the recognition accuracy. To solve this problem, we use density forest to cluster the data and use maximum a posteriori (MAP) method to build a cluster-based adapted Gaussian...... mixture models (GMMs) in HMM speech recognition. Specifically, a set of bagged versions of the training data for each state in the HMM is generated, and each of these versions is used to generate one GMM and one tree in the density forest. Thereafter, an acoustic model forest is built by replacing...... the data of each leaf (cluster) in each tree with the corresponding GMM adapted by the leaf data using the MAP method. The results show that the proposed approach achieves 3:8% (absolute) lower phone error rate compared with the standard HMM/GMM and 0:8% (absolute) lower PER compared with bagged HMM/GMM....

Comparing Waste-to-Energy technologies by applying energy system analysis

DEFF Research Database (Denmark)

Münster, Marie; Lund, Henrik

2010-01-01

Even when policies of waste prevention, re-use and recycling are prioritised a fraction of waste will still be left which can be used for energy recovery. This article asks the question: How to utilise waste for energy in the best way seen from an energy system perspective? Eight different Waste......-to-Energy technologies are compared with a focus on fuel efficiency, CO2 reductions and costs. The comparison is carried out by conducting detailed energy system analyses of the present as well as a potential future Danish energy system with a large share of combined heat and power as well as wind power. The study shows...... potential of using waste for the production of transport fuels. Biogas and thermal gasification technologies are hence interesting alternatives to waste incineration and it is recommended to support the use of biogas based on manure and organic waste. It is also recommended to support research...

Unified System-Level Modeling of Intermittent Renewable Energy Sources and Energy Storage for Power System Operation

DEFF Research Database (Denmark)

Heussen, Kai; Koch, Stephan; Ulbig, Andreas

2011-01-01

The system-level consideration of inter- mittent renewable energy sources and small-scale en- ergy storage in power systems remains a challenge as either type is incompatible with traditional operation concepts. Non-controllability and energy-constraints are still considered contingent cases...... in market-based operation. The design of operation strategies for up to 100 % renewable energy systems requires an explicit consideration of non-dispatchable generation and stor- age capacities, as well as the evaluation of operational performance in terms of energy eciency, reliability, environmental...... impact and cost. By abstracting from technology-dependent and physical unit properties, the modeling framework presented and extended in this pa- per allows the modeling of a technologically diverse unit portfolio with a unied approach, whilst establishing the feasibility of energy-storage consideration...

Energy accounting in nuclear power systems

International Nuclear Information System (INIS)

Symonds, J.L.; Essam, P.; Stocks, K.

1976-01-01

Energy analysis is a systematic way of tracing and accounting for the flows of energy through an industrial system and apportioning a quantity of the primary energy input to each of the goods and services sent out. The application of energy accounting to nuclear power stations and their growth in generating systems is discussed. Misunderstandings arising from discrepancies and weaknesses in some published simple analyses of hypothetical growth situations are outlined. Results of a more complex energy flow analysis are used to demonstrate that current nuclear energy programs are running at an energy profit. Large fossil fuel savings will occur in a real electrical grid system under anticipated nuclear power growth rates. These savings will give a new dimension in planning the use of fossil energy resources which will still be needed for transport and industrial processes, such as steelmaking, for some time to come. (author)

Energy accounting in nuclear power systems

International Nuclear Information System (INIS)

Symonds, J.L.; Essam, P.; Stocks, K.

1975-10-01

Energy analysis is a systematic way of tracing and accounting for the flows of energy through an industrial system and apportioning a quantity of the primary energy input of the goods and services sent out. The application of energy accounting to nuclear power stations and their growth in generating systems is discussed. Misunderstandings arising from discrepancies and weaknesses in some published simple analyses of hypothetical growth situations are outlined. Results of a more complex energy flow analysis are used to demonstrate that current nuclear energy programs are running at an energy profit. Large fossil fuel savings will occur in a real electrical grid system under anticipated nuclear power growth rates. These savings will give a new dimension in planning the use of fossil energy resources which will still be needed for transport and industrial processes, such as steel-making, for some time to come. (author)

Energy systems analysis of waste to energy technologies by use of EnergyPLAN

Energy Technology Data Exchange (ETDEWEB)

Muenster, M.

2009-04-15

Even when policies of waste prevention, re-use and recycling are prioritised, a fraction of waste will still be left which can be used for energy recovery. This report asks the question: How to utilise waste for energy in the best way seen from an energy system perspective? Eight different Waste-to-Energy technologies are compared with a focus on fuel efficiency, CO{sub 2} reductions and costs. The comparison is made by conducting detailed energy system analyses of the present system as well as a potential future Danish energy system with a large share of combined heat and power and wind power. The study shows the potential of using waste for the production of transport fuels such as upgraded biogas and petrol made from syngas. Biogas and thermal gasification technologies are interesting alternatives to waste incineration and it is recommended to support the use of biogas based on manure and organic waste. It is also recommended to support research into gasification of waste without the addition of coal and biomass. Together, the two solutions may contribute to an alternate use of one third of the waste which is currently incinerated. The remaining fractions should still be incinerated with priority given to combined heat and power plants with high electrical efficiencies. (author)

Improving energy efficiency in industrial energy systems an interdisciplinary perspective on barriers, energy audits, energy management, policies, and programs

CERN Document Server

Thollander, Patrik

2012-01-01

Industrial energy efficiency is one of the most important means of reducing the threat of increased global warming. Research however states that despite the existence of numerous technical energy efficiency measures, its deployment is hindered by the existence of various barriers to energy efficiency. The complexity of increasing energy efficiency in manufacturing industry calls for an interdisciplinary approach to the issue. Improving energy efficiency in industrial energy systems applies an interdisciplinary perspective in examining energy efficiency in industrial energy systems, and discuss

Energy savings for solar heating systems; Solvarmeanlaegs energibesparelser

Energy Technology Data Exchange (ETDEWEB)

Furbo, S.; Fan, J.

2011-01-15

Energy savings for a number of new solar heating systems in one family houses have been determined by means of information on the energy consumption of the houses before and after installation of the solar heating systems. The investigated solar heating systems are marketed by Velux Danmark A/S, Sonnnenkraft Scandinavia A/S and Batec Solvarme A/S. Solar domestic hot water systems as well as solar combi systems are included in the investigations The houses have different auxiliary energy supply systems: Natural gas boilers, oil fired burners, electrical heating and district heating. Some of the houses have a second auxiliary energy supply system. The collector areas vary from 1.83 m{sup 2} to 9.28 m{sup 2}. Some of the solar heating systems are based on energy units with a new integrated natural gas boiler and a heat storage for the solar heating system. The existing energy systems in the houses are for most of the houses used as the auxiliary energy systems for the solar heating systems. The yearly energy savings for the houses where the only change is the installation of the solar heating system vary from 300 kWh per m{sup 2} solar collector to 1300 kWh per m{sup 2} solar collector. The average yearly energy savings is about 670 kWh per m{sup 2} solar collector for these solar heating systems. The energy savings per m{sup 2} solar collector are not influenced by the solar heating system type, the company marketing the system, the auxiliary energy supply system, the collector area, the collector tilt, the collector azimuth, the energy consumption of the house or the location of the house. The yearly energy savings for the houses with solar heating systems based on energy units including a new natural gas boiler vary from 790 kWh per m{sup 2} solar collector to 2090 kWh per m{sup 2} solar collector. The average yearly energy savings is about 1520 kWh per m{sup 2} solar collector for these solar heating systems. The energy savings per m{sup 2} solar collector for

Energy harvesting solar, wind, and ocean energy conversion systems

CERN Document Server

Khaligh, Alireza

2009-01-01

Also called energy scavenging, energy harvesting captures, stores, and uses ""clean"" energy sources by employing interfaces, storage devices, and other units. Unlike conventional electric power generation systems, renewable energy harvesting does not use fossil fuels and the generation units can be decentralized, thereby significantly reducing transmission and distribution losses. But advanced technical methods must be developed to increase the efficiency of devices in harvesting energy from environmentally friendly, ""green"" resources and converting them into electrical energy.Recognizing t

Window Energy Rating System and Calculation of Energy Performance of Windows

DEFF Research Database (Denmark)

Laustsen, Jacob Birck; Svendsen, Svend

The goal of reducing the energy consumption in buildings is the background for the introduction of an energy rating system of fenestration products in Denmark. The energy rating system requires that producers declare, among other things, the heat loss coefficient, U, and the total solar energy...... development, e.g. when the resulting effects of a reduced frame area are evaluated....

Solar energy thermally powered electrical generating system

Science.gov (United States)

Owens, William R. (Inventor)

1989-01-01

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

Energy storage systems: power grid and energy market use cases

Directory of Open Access Journals (Sweden)

Komarnicki Przemysław

2016-09-01

Full Text Available Current power grid and market development, characterized by large growth of distributed energy sources in recent years, especially in Europa, are according energy storage systems an increasingly larger field of implementation. Existing storage technologies, e.g. pumped-storage power plants, have to be upgraded and extended by new but not yet commercially viable technologies (e.g. batteries or adiabatic compressed air energy storage that meet expected demands. Optimal sizing of storage systems and technically and economically optimal operating strategies are the major challenges to the integration of such systems in the future smart grid. This paper surveys firstly the literature on the latest niche applications. Then, potential new use case and operating scenarios for energy storage systems in smart grids, which have been field tested, are presented and discussed and subsequently assessed technically and economically.

Local Alternative for Energy Supply : Performance Assessment of Integrated Community Energy Systems

NARCIS (Netherlands)

Koirala, B.P.; Chaves Avila, J.P.; Gomez, T.; Hakvoort, R.A.; Herder, P.M.

2016-01-01

Integrated community energy systems (ICESs) are emerging as a modern development to re-organize local energy systems allowing simultaneous integration of distributed energy resources (DERs) and engagement of local communities. Although local energy initiatives, such as ICESs are rapidly emerging due

Autonomous renewable energy conversion system

Energy Technology Data Exchange (ETDEWEB)

Valtchev, V. [Technical University of Varna (Bulgaria). Dept. of Electronics; Bossche, A. van den; Ghijselen, J.; Melkebeek, J. [University of Gent (Belgium). Dept. of Electrical Power Engineering

2000-02-01

This paper briefly reviews the need for renewable power generation and describes a medium-power Autonomous Renewable Energy Conversion System (ARECS), integrating conversion of wind and solar energy sources. The objectives of the paper are to extract maximum power from the proposed wind energy conversion scheme and to transfer this power and the power derived by the photovoltaic system in a high efficiency way to a local isolated load. The wind energy conversion operates at variable shaft speed yielding an improved annual energy production over constant speed systems. An induction generator (IG) has been used because of its reduced cost, robustness, absence of separate DC source for excitation, easier dismounting and maintenance. The maximum energy transfer of the wind energy is assured by a simple and reliable control strategy adjusting the stator frequency of the IG so that the power drawn is equal to the peak power production of the wind turbine at any wind speed. The presented control strategy also provides an optimal efficiency operation of the IG by applying a quadratic dependence between the IG terminal voltage and frequency V {approx} f{sup 2}. For improving the total system efficiency, high efficiency converters have been designed and implemented. The modular principle of the proposed DC/DC conversion provides the possibility for modifying the system structure depending on different conditions. The configuration of the presented ARECS and the implementation of the proposed control algorithm for optimal power transfer are fully discussed. The stability and dynamic performance as well as the different operation modes of the proposed control and the operation of the converters are illustrated and verified on an experimental prototype. (author)

Heat-pump-centered integrated community energy systems: system development summary

Energy Technology Data Exchange (ETDEWEB)

Calm, J.M.

1980-02-01

An introduction to district heating systems employing heat pumps to enable use of low-temperature energy sources is presented. These systems operate as thermal utilities to provide space heating and may also supply space cooling, service-water heating, and other thermal services. Otherwise-wasted heat from industrial and commercial processes, natural sources including solar and geothermal heat, and heat stored on an annual cycle from summer cooling may be effectively utilized by the systems described. These sources are abundant, and their use would conserve scarce resources and reduce adverse environmental impacts. More than one-quarter of the energy consumed in the United States is used to heat and cool buildings and to heat service water. Natural gas and oil provide approximately 83% of this energy. The systems described show potential to reduce net energy consumption for these services by 20 to 50% and to allow fuel substitution with less-scarce resources not practical in smaller, individual-building systems. Seven studies performed for the system development phase of the Department of Energy's Heat-Pump-Centered Integrated Community Energy Systems Project and to related studies are summarized. A concluding chapter tabulates data from these separately published studies.

Master of Engineering Energy Systems Engineering Program: Smart Campus Energy Systems Demonstration DE-SC0005523

Energy Technology Data Exchange (ETDEWEB)

Dodge, Martha [Lehigh Univ., Bethlehem, PA (United States); Coulter, John [Lehigh Univ., Bethlehem, PA (United States)

2014-09-25

Program Purpose and Position: The mission of the Master of Engineering in Energy Systems Engineering program is to invigorate the pipeline of new engineering graduates interested in energy oriented careers and thus produce a new generation of technical leaders for the energy and power industries. Over the next decade, nearly 50% of the skilled workers and technical leaders in the gas and electric utility industries will retire -- a much larger void than the current available and qualified professionals could fill [CEWD, 2012 survey]. The Masters of Engineering in Energy System Engineering program provides an opportunity for cross-discipline education for graduates interested in a career in the energy industry. It focuses on electric power and the challenges and opportunities to develop a sustainable, reliable and resilient system that meets human needs in an increasingly sustainable manner through the use of environmentally sound energy resources and delivery. Both graduates and employers benefit from a well-trained professional workforce that is ready to hit the road running and be immediately productive in meeting these challenges, through this innovative and unique program.

Energy accounting and optimization for mobile systems

Science.gov (United States)

Dong, Mian

Energy accounting determines how much a software process contributes to the total system energy consumption. It is the foundation for evaluating software and has been widely used by operating system based energy management. While various energy accounting policies have been tried, there is no known way to evaluate them directly simply because it is hard to track every hardware use by software in a heterogeneous multi-core system like modern smartphones and tablets. In this thesis, we provide the ground truth for energy accounting based on multi-player game theory and offer the first evaluation of existing energy accounting policies, revealing their important flaws. The proposed ground truth is based on Shapley value, a single value solution to multi-player games of which four axiomatic properties are natural and self-evident to energy accounting. To obtain the Shapley value-based ground truth, one only needs to know if a process is active during the time under question and the system energy consumption during the same time. We further provide a utility optimization formulation of energy management and show, surprisingly, that energy accounting does not matter for existing energy management solutions that control the energy use of a process by giving it an energy budget, or budget based energy management (BEM). We show an optimal energy management (OEM) framework can always outperform BEM. While OEM does not require any form of energy accounting, it is related to Shapley value in that both require the system energy consumption for all possible combination of processes under question. We provide a novel system solution that meet this requirement by acquiring system energy consumption in situ for an OS scheduler period, i.e.,10 ms. We report a prototype implementation of both Shapley value-based energy accounting and OEM based scheduling. Using this prototype and smartphone workload, we experimentally demonstrate how erroneous existing energy accounting policies can

Renewable energy delivery systems and methods

Science.gov (United States)

Walker, Howard Andrew

2013-12-10

A system, method and/or apparatus for the delivery of energy at a site, at least a portion of the energy being delivered by at least one or more of a plurality of renewable energy technologies, the system and method including calculating the load required by the site for the period; calculating the amount of renewable energy for the period, including obtaining a capacity and a percentage of the period for the renewable energy to be delivered; comparing the total load to the renewable energy available; and, implementing one or both of additional and alternative renewable energy sources for delivery of energy to the site.

Wind energy systems information user study

Energy Technology Data Exchange (ETDEWEB)

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

1981-01-01

This report describes the results of a series of telephone interviews with potential users of information on wind energy conversion. These interviews, part of a larger study covering nine different solar technologies, attempted to identify: the type of information each distinctive group of information users needed, and the best way of getting information to that group. Groups studied include: wind energy conversion system researchers; wind energy conversion system manufacturer representatives; wind energy conversion system distributors; wind turbine engineers; utility representatives; educators; county agents and extension service agents; and wind turbine owners.

Intelligent energy management of optimally located renewable energy systems incorporating PHEV

International Nuclear Information System (INIS)

El-Zonkoly, Amany

2014-01-01

Highlights: • The algorithm optimally selects the number, locations and sizes of DGs. • Wind units, PV units, diesel units and PHEV parking lots are considered as DGs. • The algorithm determines the corresponding energy scheduling of resources. • The problem is formulated as an optimization problem solved using ABC. • The objective is to minimize the overall energy cost of the system. - Abstract: The recent interest in plug-in-hybrid electric vehicles (PHEV) results in the increase in the utilization of vehicles batteries for grid support. In addition, the integration of renewable energy systems (RES) into electricity grid is a promising technique for addressing the environmental concerns. This paper presents a multi-objective algorithm to optimally allocate a number of renewable energy systems including parking lots for PHEV in a distribution system. The proposed algorithm determines the number, locations and sizes of the RES and parking lots. In addition, a rule based expert system is used to find the corresponding energy scheduling of the system resources. The objective of the proposed algorithm is to minimize the overall energy cost of the system. The problem is formulated as an optimization problem which is solved using artificial bee colony (ABC) algorithm taking into consideration the power system and PHEV operational constraints. The proposed algorithm is applied to a 45-bus distribution network of Alexandria, Egypt. The test results indicate an improvement in the operational conditions of the system

Evaluation of two typical distributed energy systems

Science.gov (United States)

Han, Miaomiao; Tan, Xiu

2018-03-01

According to the two-natural gas distributed energy system driven by gas engine driven and gas turbine, in this paper, the first and second laws of thermodynamics are used to measure the distributed energy system from the two parties of “quantity” and “quality”. The calculation results show that the internal combustion engine driven distributed energy station has a higher energy efficiency, but the energy efficiency is low; the gas turbine driven distributed energy station energy efficiency is high, but the primary energy utilization rate is relatively low. When configuring the system, we should determine the applicable natural gas distributed energy system technology plan and unit configuration plan according to the actual load factors of the project and the actual factors such as the location, background and environmental requirements of the project. “quality” measure, the utilization of waste heat energy efficiency index is proposed.

Biodigester as an energy storage system

Energy Technology Data Exchange (ETDEWEB)

Borges Neto, M.R.; Lopes, L.C.N. [Federal Institute of Education, Science and Technology of Sertao Pernambucano (IFSertao-PE), Petrolina, PE (Brazil)], Emails: rangel@cefetpet.br; Pinheiro Neto, J.S.; Carvalho, P.C.M. [Federal University of Ceara (UFC), Fortaleza, CE (Brazil). Dept. of Electrical Engineering], Emails: neto@tbmtextil.com.br, carvalho@dee.ufc.br; Silveira, G.C.; Moreira, A.P.; Borges, T.S.H. [Federal Institute of Education, Science and Technology of Ceara (IFCE), Fortaleza, CE (Brazil)], Emails: gcsilveira@cefet-ce.br, apmoreira@ifce.edu.br, thatyanys@yahoo.com.br

2009-07-01

Electricity supply for rural and remote areas is becoming an increasing priority to developing countries. The high initial cost of renewable energy based unities usually needs an energy storage system; due its operational and even replacement cost contributes to a higher final cost. The choice of energy storage systems depends on the sort and size of adopted power supply. This paper has a main goal to introduce a renewable energy based storage system weakly explored in Brazil: biogas from anaerobic digestion. It also brings a review of the main energy storage systems applied to electrical energy generation. As reference an experiment with an adapted Indian digester of 5 m{sup 3} that produced nearly 2m{sup 3} of biogas daily. The obtained biogas met the consumption of at least 4 typical Brazilian low income households with installed load of 500 W each and was enough to replace the use of 420 Ah lead-acid batteries. (author)

Energy transfer in plasmonic systems

International Nuclear Information System (INIS)

Pustovit, Vitaliy N; Urbas, Augustine M; Shahbazyan, Tigran V

2014-01-01

We present our results on energy transfer between donor and acceptor molecules or quantum dots near a plasmonic nanoparticle. In such systems, the Förster resonance energy transfer is strongly modified due to plasmon-mediated coupling between donors and acceptors. The transfer efficiency is determined by a competition between transfer, radiation and dissipation that depends sensitively on system parameters. When donor and accepror spectral bands overlap with dipole surface plasmon resonance, the dominant transfer mechanism is through plasmon-enhanced radiative coupling. When transfer takes place from an ensemble of donors to an acceptor, a cooperative amplification of energy transfer takes place in a wide range of system parameters. (paper)

Smart power systems and renewable energy system integration

CERN Document Server

2016-01-01

This monograph presents a wider spectrum of researches, developments, and case specific studies in the area of smart power systems and integration of renewable energy systems. The book will be for the benefit of a wider audience including researchers, postgraduate students, practicing engineers, academics, and regulatory policy makers. It covers a wide range of topics from fundamentals, and modelling and simulation aspects of traditional and smart power systems to grid integration of renewables; Micro Grids; challenges in planning and operation of a smart power system; risks, security, and stability in smart operation of a power system; and applied research in energy storage. .

The Island Smart Energy System and Market

DEFF Research Database (Denmark)

Ma, Zheng; Billanes, Joy Dalmacio; Jørgensen, Bo Nørregaard

2017-01-01

developing island smart energy systems with the integration of renewable energy resources can increase the energy supply and address the global island energy issues. The island smart energy system operates either in a single-island or in multi-islands. However the island characteristics and influ...

Renewable Energy Tracking Systems

Science.gov (United States)

Renewable energy generation ownership can be accounted through tracking systems. Tracking systems are highly automated, contain specific information about each MWh, and are accessible over the internet to market participants.

The attitude to nuclear energy in comparison with other energy systems

International Nuclear Information System (INIS)

Fuchs, D.

1991-01-01

The subject of the study is the analysis of trends, the level and the determinants of the attitude to nuclear energy on the basis of survey data from representative samples. The emphasis is on analyzing the attitude to nuclear energy in the context of the so-called new political line of conflict. The most striking result of the trend analysis of the attitude to four energy systems - nuclear energy, coal, mineral oil, natural gas - was the drastic decline in the acceptance of nuclear energy in the time period covered by the available time series. The trends observed lead one to suppose that the evaluation of energy systems is no simple numbers game of the kind that means a more negative assessment of one energy system unavoidably leads to a more positive assessment of the other and vice versa, but that the individual energy systems are judged at least in part independently of one another. Effective public relations information and events may play an important part in changing attitudes to the individual energy systems. Structural factors are primarily a change in political values and an increased political competence on the part of the citizens. Both these factors taken together have created a greater perception of and sensitivity to the side-effects of the technical-industrial growth process. This aspect of the side-effects has been politicized by the New Social Movements particularly with reference to nuclear energy. Provided that political lines of conflict are important and lasting mechanisms for structuring, then nuclear energy will probably remain a constant theme, because of its importance in symbolizing fundamental problems at the technical-industrial growth process. (orig./HSCH) [de

Heat-pump-centered integrated community energy systems

Energy Technology Data Exchange (ETDEWEB)

Schaetzle, W.J.; Brett, C.E.; Seppanen, M.S.

1979-12-01

The heat-pump-centered integrated community energy system (HP-ICES) supplies district heating and cooling using heat pumps and a thermal energy storage system which is provided by nature in underground porous formations filled with water, i.e., aquifers. The energy is transported by a two-pipe system, one for warm water and one for cool water, between the aquifers and the controlled environments. Each energy module contains the controlled environments, an aquifer, wells for access to the aquifer, the two pipe water distribution system and water source heat pumps. The heat pumps upgrade the energy in the distribution system for use in the controlled environments. Economically, the system shows improvement on both energy usage and capital costs. The system saves over 60% of the energy required for resistance heating; saves over 30% of the energy required for most air-source heat pumps and saves over 60% of the energy required for gas, coal, or oil heating, when comparing to energy input required at the power plant for heat pump usage. The proposed system has been analyzed as demonstration projects for a downtown portion of Louisville, Kentucky, and a section of Fort Rucker, Alabama. The downtown Louisville demonstration project is tied directly to major buildings while the Fort Rucker demonstration project is tied to a dispersed subdivision of homes. The Louisville project shows a payback of approximately 3 y, while Fort Rucker is approximately 30 y. The primary difference is that at Fort Rucker new heat pumps are charged to the system. In Louisville, either new construction requiring heating and cooling systems or existing chillers are utilized. (LCL)

System-of-Systems Approach for Integrated Energy Systems Modeling and Simulation: Preprint

Energy Technology Data Exchange (ETDEWEB)

Mittal, Saurabh; Ruth, Mark; Pratt, Annabelle; Lunacek, Monte; Krishnamurthy, Dheepak; Jones, Wesley

2015-08-21

Today’s electricity grid is the most complex system ever built—and the future grid is likely to be even more complex because it will incorporate distributed energy resources (DERs) such as wind, solar, and various other sources of generation and energy storage. The complexity is further augmented by the possible evolution to new retail market structures that provide incentives to owners of DERs to support the grid. To understand and test new retail market structures and technologies such as DERs, demand-response equipment, and energy management systems while providing reliable electricity to all customers, an Integrated Energy System Model (IESM) is being developed at NREL. The IESM is composed of a power flow simulator (GridLAB-D), home energy management systems implemented using GAMS/Pyomo, a market layer, and hardware-in-the-loop simulation (testing appliances such as HVAC, dishwasher, etc.). The IESM is a system-of-systems (SoS) simulator wherein the constituent systems are brought together in a virtual testbed. We will describe an SoS approach for developing a distributed simulation environment. We will elaborate on the methodology and the control mechanisms used in the co-simulation illustrated by a case study.

Energy Systems Group. Annual Progress Report 1984

DEFF Research Database (Denmark)

Grohnheit, Poul Erik; Larsen, Hans Hvidtfeldt; Villadsen, B.

The report describes the work of the Energy Systems Group at Risø National Laboratory during 1984. The activities may be roughly classified as development and use of energy-economy models, energy systems analysis, energy technology assessment and energy planning. The report includes a list of staff...

Federal Tax Incentives for Energy Storage Systems

Energy Technology Data Exchange (ETDEWEB)

Anderson, Katherine H [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Elgqvist, Emma M [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Settle, Donald E [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2018-01-16

Investments in renewable energy are more attractive due to the contribution of two key federal tax incentives. The investment tax credit (ITC) and the Modified Accelerated Cost Recovery System (MACRS) depreciation deduction may apply to energy storage systems such as batteries depending on who owns the battery and how the battery is used. The guidelines in this fact sheet apply to energy storage systems installed at the same time as the renewable energy system.

Compressed Air Energy Storage System Control and Performance Assessment Using Energy Harvested Index

Directory of Open Access Journals (Sweden)

Hanif SedighNejad

2014-01-01

Full Text Available In this paper a new concept for control and performance assessment of compressed air energy storage (CAES systems in a hybrid energy system is introduced. The proposed criterion, based on the concept of energy harvest index (HEI, measures the capability of a storage system to capture renewable energy. The overall efficiency of the CAES system and optimum control and design from the technical and economic point of view is presented. A possible application of this idea is an isolated community with significant wind energy resource. A case study reveals the usefulness of the proposed criterion in design, control and implementation of a small CAES system in a hybrid power system (HPM for an isolated community. Energy harvested index and its effectiveness in increasing the wind penetration rate in the total energy production is discussed.

Renewable Energy Devices and Systems

DEFF Research Database (Denmark)

Blaabjerg, Frede; Ionel, Dan M.

2015-01-01

In this paper, essential statistics demonstrating the increasing role of renewable energy generation are firstly discussed. A state of the art review section covers fundamentals of wind turbines and PV systems. Included are schematic diagrams illustrating the main components and system topologies...... and the fundamental and increasing role of power electronics as an enabler for renewable energy integration, and for the future power system and smart grid. Recent examples of research and development, including new devices and system installations for utility power plants, as well for as residential and commercial......, fuel cells, and storage with batteries and hydrogen, respectively. Recommended further readings on topics of electric power engineering for renewable energy are included in a final section. This paper also represents an editorial introduction for two special issues of the Electric Power Component...

Energy consumption habits and human health nexus in Sub-Saharan Africa.

Science.gov (United States)

Hanif, Imran

2018-05-22

This study explores the impact of fossil fuels consumption, solid fuels consumption for cooking purposes, economic growth, and carbon emissions on human health, with a key emphasis on the occurrence of tuberculosis and the high mortality rate in Sub-Saharan Africa. For its practical insights, the study develops a system Generalized Method of Moment (GMM) for a panel of 34 middle- and lower-middle-income countries from 1995 to 2015. The study adopts a flexible methodology to tackle endogeneity in the variables. The robust results report that the use of solid fuels (charcoal, peat, wood, wood pellets, crop residues) for cooking purposes and the consumption of fossil fuels (oil, coal, gas) are significantly increasing the occurrence of tuberculosis. In addition, the results highlight that the consumption of both solid fuels and fossil fuels has adverse affects on life expectancy by increasing the mortality rate in Sub-Saharan African countries. Results report that renewable energy sources like sun, wind, and water (all with potential to prevent households from direct exposure to particulate matters and harmful gases) as well as a rise in economic growth serve as helping factors to control the occurrence of tuberculosis and to decrease the mortality rate. Moreover, the use of renewable energy sources is serving to lessen emissions of carbon dioxide, nitrogen dioxides, and particulate matters, which can ultimately decrease the mortality rate and extend the life expectancy in Sub-Saharan Africa.

Energy Systems Group annual progress report 1984

International Nuclear Information System (INIS)

Grohnheit, P.E.; Larsen, H.; Villadsen, B.

1985-02-01

The report describes the work of the Energy Systems Group at Risoe National Laboratory during 1984. The activities may be roughly classified as development and use of energy-economy models, energy systems analysis, energy technology assessment and energy planning. The report includes a list of staff members. (author)

Energy performance and energy saving of life-support systems in ...

African Journals Online (AJOL)

The contemporary automation systems of buildings ensure the most efficient control automation for heating, ventilation, lighting, hot water supply systems. This leads to significant increase of operation efficiency and reduction of energy costs. The integrated energy saving processes and functions are optimized depending ...

Flexible Grouping for Enhanced Energy Utilization Efficiency in Battery Energy Storage Systems

Directory of Open Access Journals (Sweden)

Weiping Diao

2016-06-01

Full Text Available As a critical subsystem in electric vehicles and smart grids, a battery energy storage system plays an essential role in enhancement of reliable operation and system performance. In such applications, a battery energy storage system is required to provide high energy utilization efficiency, as well as reliability. However, capacity inconsistency of batteries affects energy utilization efficiency dramatically; and the situation becomes more severe after hundreds of cycles because battery capacities change randomly due to non-uniform aging. Capacity mismatch can be solved by decomposing a cluster of batteries in series into several low voltage battery packs. This paper introduces a new analysis method to optimize energy utilization efficiency by finding the best number of batteries in a pack, based on capacity distribution, order statistics, central limit theorem, and converter efficiency. Considering both battery energy utilization and power electronics efficiency, it establishes that there is a maximum energy utilization efficiency under a given capacity distribution among a certain number of batteries, which provides a basic analysis for system-level optimization of a battery system throughout its life cycle. Quantitative analysis results based on aging data are illustrated, and a prototype of flexible energy storage systems is built to verify this analysis.

Modelling energy systems for developing countries

International Nuclear Information System (INIS)

Urban, F.; Benders, R.M.J.; Moll, H.C.

2007-01-01

Developing countries' energy use is rapidly increasing, which affects global climate change and global and regional energy settings. Energy models are helpful for exploring the future of developing and industrialised countries. However, energy systems of developing countries differ from those of industrialised countries, which has consequences for energy modelling. New requirements need to be met by present-day energy models to adequately explore the future of developing countries' energy systems. This paper aims to assess if the main characteristics of developing countries are adequately incorporated in present-day energy models. We first discuss these main characteristics, focusing particularly on developing Asia, and then present a model comparison of 12 selected energy models to test their suitability for developing countries. We conclude that many models are biased towards industrialised countries, neglecting main characteristics of developing countries, e.g. the informal economy, supply shortages, poor performance of the power sector, structural economic change, electrification, traditional bio-fuels, urban-rural divide. To more adequately address the energy systems of developing countries, energy models have to be adjusted and new models have to be built. We therefore indicate how to improve energy models for increasing their suitability for developing countries and give advice on modelling techniques and data requirements

Sustainable automotive energy system in China

Energy Technology Data Exchange (ETDEWEB)

Zhang, Xiliang (ed.) [Tsinghua Univ. Beijing (China). China Automotive Energy Research Center

2013-06-01

The latest research available on automotive energy system analysis in China. Thorough introduction on automotive energy system in China. Provides the broad perspective to aid in planning sustainable road transport in China. Sustainable Automotive Energy System in China aims at identifying and addressing the key issues of automotive energy in China in a systematic way, covering demography, economics, technology and policy, based on systematic and in-depth, multidisciplinary and comprehensive studies. Five scenarios of China's automotive energy development are created to analyze the possible contributions in the fields of automotive energy, vehicle fuel economy improvement, electric vehicles, fuel cell vehicles and the 2nd generation biofuel development. Thanks to this book, readers can gain a better understanding of the nature of China's automotive energy development and be informed about: (1) the current status of automotive energy consumption, vehicle technology development, automotive energy technology development and policy; (2) the future of automotive energy development, fuel consumption, propulsion technology penetration and automotive energy technology development, and (3) the pathways of sustainable automotive energy transformation in China, in particular, the technological and the policy-related options. This book is intended for researchers, engineers and graduates students in the low-carbon transportation and environmental protection field.

System Energy Assessment (SEA, Defining a Standard Measure of EROI for Energy Businesses as Whole Systems

Directory of Open Access Journals (Sweden)

Jay Zarnikau

2011-10-01

Full Text Available A more objective method for measuring the energy needs of businesses, System Energy Assessment (SEA, measures the combined impacts of material supply chains and service supply chains, to assess businesses as whole self-managing net-energy systems. The method is demonstrated using a model Wind Farm, and defines a physical measure of their energy productivity for society (EROI-S, a ratio of total energy delivered to total energy expended. Energy use records for technology and proxy measures for clearly understood but not individually recorded energy uses for services are combined for a whole system estimate of consumption required for production. Current methods count only energy needs for technology. Business services outsource their own energy needs to operate, leaving no traceable record. That uncounted business energy demand is often 80% of the total, an amount of “dark energy” hidden from view, discovered by finding the average energy estimated needs for businesses far below the world average energy consumed per dollar of GDP. Presently for lack of information the energy needs of business services are counted to be “0”. Our default assumption is to treat them as “average”. The result is a hard measure of total business demand for energy services, a “Scope 4” energy use or GHG impact assessment. Counting recorded energy uses and discounting unrecorded ones misrepresents labor intensive work as highly energy efficient. The result confirms a similar finding by Hall et al. in 1981 [1]. We use exhaustive search for what a business needs to operate as a whole, tracing internal business relationships rather than energy data, to locate its natural physical boundary as a working unit, and so define a business as a physical rather than statistical subject of scientific study. See also online resource materials and notes [2].

Two sustainable energy system analysis models

DEFF Research Database (Denmark)

Lund, Henrik; Goran Krajacic, Neven Duic; da Graca Carvalho, Maria

2005-01-01

This paper presents a comparative study of two energy system analysis models both designed with the purpose of analysing electricity systems with a substantial share of fluctuating renewable energy....

Stochastic Generalized Method of Moments

KAUST Repository

Yin, Guosheng; Ma, Yanyuan; Liang, Faming; Yuan, Ying

2011-01-01

The generalized method of moments (GMM) is a very popular estimation and inference procedure based on moment conditions. When likelihood-based methods are difficult to implement, one can often derive various moment conditions and construct the GMM objective function. However, minimization of the objective function in the GMM may be challenging, especially over a large parameter space. Due to the special structure of the GMM, we propose a new sampling-based algorithm, the stochastic GMM sampler, which replaces the multivariate minimization problem by a series of conditional sampling procedures. We develop the theoretical properties of the proposed iterative Monte Carlo method, and demonstrate its superior performance over other GMM estimation procedures in simulation studies. As an illustration, we apply the stochastic GMM sampler to a Medfly life longevity study. Supplemental materials for the article are available online. © 2011 American Statistical Association.

Stochastic Generalized Method of Moments

KAUST Repository

Yin, Guosheng

2011-08-16

The generalized method of moments (GMM) is a very popular estimation and inference procedure based on moment conditions. When likelihood-based methods are difficult to implement, one can often derive various moment conditions and construct the GMM objective function. However, minimization of the objective function in the GMM may be challenging, especially over a large parameter space. Due to the special structure of the GMM, we propose a new sampling-based algorithm, the stochastic GMM sampler, which replaces the multivariate minimization problem by a series of conditional sampling procedures. We develop the theoretical properties of the proposed iterative Monte Carlo method, and demonstrate its superior performance over other GMM estimation procedures in simulation studies. As an illustration, we apply the stochastic GMM sampler to a Medfly life longevity study. Supplemental materials for the article are available online. © 2011 American Statistical Association.

Renewable energy off-grid power systems: options for energy suppliers

International Nuclear Information System (INIS)

Trouchet, K.

1992-01-01

SURVIVOR ENERGY SYSTEMS package a range of wind-based renewable energy systems for the supply of 24-hour power to off-grid homesteads and communities. This paper presents a leasing package for these power users and illustrates their cost effectiveness in comparison with stand-alone diesel and comparative hybrid power options. This offer is seen as a alternative for energy planners and supply agencies for their off-grid clients. 6 refs., 3 tabs., 3 figs

Energy analysis of a supermarket refrigeration system

DEFF Research Database (Denmark)

Jensen, Jakob Munch; Jakobsen, Arne; Rasmussen, Bjarne D.

1999-01-01

From 1995 to 1998, an energy test method for supermarket refrigeration systems was developed in a project financed by the Danish Energy Agency. The purpose of the energy test method is to provide the means for evaluating the energy efficiency of these systems. The test method requires measurements...... of air temperatures and energy consumption to be carried out on the selected supermarket refrigeration system. In addition to the measurements required by the method, more measurements of individual energy consumptions have been carried in the case described in this paper. The purpose of the additional...

An energy saving system for hospital laundries

Energy Technology Data Exchange (ETDEWEB)

Katsanis, J.S.; Tsarabaris, P.T.; Polykrati, A.D.; Proios, A.N. [National Technical Univ. of Athens, Athens (Greece). School of Electrical and Computer Engineering; Koufakis, E.I. [Public Power Corp. S.A., Crete (Greece)

2009-07-01

Hospital laundries are one of the largest consumers of water and electrical and thermal energy. This paper examined the energy savings achieved by a system using the hot wastewater from the washing process. Hospital laundries consume thermal energy using steam, which is produced in boilers by burning diesel oil or natural gas. Electrical energy for the mechanical drives, ventilation and also the lighting required in the laundry area are big consumers of energy. The paper presented the proposed system and discussed the parameters of the system and system dimensioning. The paper also provided and discussed an interpretation of steam and energy savings. The proposed system was considered to be economically viable, simple in its construction, installation and operation. From the application of the suggested system, the cost savings resulted in a satisfactory payback period for the capital invested of approximately three to five years. 14 refs., 4 tabs., 2 figs.

Modeling of battery energy storage in the National Energy Modeling System

Energy Technology Data Exchange (ETDEWEB)

Swaminathan, S.; Flynn, W.T.; Sen, R.K. [Sentech, Inc., Bethesda, MD (United States)

1997-12-01

The National Energy Modeling System (NEMS) developed by the U.S. Department of Energy`s Energy Information Administration is a well-recognized model that is used to project the potential impact of new electric generation technologies. The NEMS model does not presently have the capability to model energy storage on the national grid. The scope of this study was to assess the feasibility of, and make recommendations for, the modeling of battery energy storage systems in the Electricity Market of the NEMS. Incorporating storage within the NEMS will allow the national benefits of storage technologies to be evaluated.

The map of energy flow in HVAC systems

International Nuclear Information System (INIS)

Perez-Lombard, Luis; Ortiz, Jose; Maestre, Ismael R.

2011-01-01

Highlights: → Discussion of the four stages in the 'HVAC systems energy chain'. → Examination of HVAC systems as energy conversion devices. → Analysis of HVAC Sankey diagrams. → Discussion of HVAC loads and HVAC energy losses. -- Abstract: Heating, ventilation and air conditioning (HVAC) systems are the most energy consuming building services representing approximately half of the final energy use in the building sector and between one tenth and one fifth of the energy consumption in developed countries. Despite their significant energy use, there is a lack of a consistent and homogeneous framework to efficiently guide research and energy policies, mainly due to the complexity and variety of HVAC systems but also to insufficient rigour in their energy analysis. This paper reviews energy related aspects of HVAC systems with the aim of establishing a common ground for the analysis of their energy efficiency. The paper focuses on the map of energy flow to deliver thermal comfort: the HVAC energy chain. Our approach deals first with thermal comfort as the final service delivered to building occupants. Secondly, conditioned spaces are examined as the systems where useful heat (or coolth) is degraded to provide comfort. This is followed by the analysis of HVAC systems as complex energy conversion devices where energy carriers are transformed into useful heat and coolth, and finally, the impact of HVAC energy consumption on energy resources is discussed.

A hybrid energy efficient building ventilation system

International Nuclear Information System (INIS)

Calay, Rajnish Kaur; Wang, Wen Chung

2013-01-01

The present paper presents a high performance cooling/heating ventilation system using a rotary heat exchanger (RHE), together with a reverse-cycle heat pump (RCHP) that can be integrated with various heat sources. Energy consumption in the building sector is largely dominated by the energy consumed in maintaining comfortable conditions indoors. For example in many developed countries the building heating, ventilation and air conditioning (HVAC) systems consume up to 50% of the total energy consumed in buildings. Therefore energy efficient HVAC solutions in buildings are critical for realising CO 2 targets at local and global level. There are many heating/cooling concepts that rely upon renewable energy sources and/or use natural low temperature heat sources in the winter and heat sinks in the summer. In the proposed system, waste energy from the exhaust air stream is used to precondition the outdoor air before it is supplied into the building. The hybrid system provides heating in the winter and cooling in the summer without any need for additional heating or cooling devices as required in conventional systems. Its performance is better than a typical reheat or air conditioning system in providing the same indoor air quality (IAQ) levels. It is shown that an energy saving up to 60% (heat energy) is achieved by using the proposed hybrid system in building ventilation applications. -- Highlights: • Hybrid ventilation system: the hybrid ventilation system uses a rotating regenerator and a reversible heat pump. • Heat recovery: heat recovery from exhaust air stream by rotary wheel type heat exchanger. • Reversible cycle heat pump (RCHP): additional heating or cooling of the supply air is provided by the RCHP. • Energy efficiency: energy savings of up to 60% using the proposed system are achievable

Restructuring the Energy System. Report of the Energy Commission

International Nuclear Information System (INIS)

1995-01-01

The commission was instructed to examine the current energy policy programs for restructuring and developing the energy system (i.e. phasing out nuclear power and moving to renewable sources) and to analyze the needs for changes; to propose measures for ensuring an efficient electricity supply under the new conditions of a liberalized electricity market; and to present proposals for a schedule for reorganizing the energy system. The report gives a full picture of the Swedish energy system including supply, consumption, prices, environmental impacts, R and D, and international aspects. The commission concludes that one nuclear power plant can be closed during the 1990's without upsetting the power balances. Phasing out all nuclear plants by year 2010 will create problems with the price levels of electricity supply, and will conflict with the CO 2 reduction objective. The proposals for economic control measures for performing the restructuring include: An environmental bonus (or investment support) for environmentally sound electricity production financed by an electricity tax, a tax on nuclear power increasing with the age of the reactors, a reorganization fund to finance new and environmentally acceptable electricity production. Also, energy research should be allotted greater resources, in particular for new technology for electricity production. The commission points towards the possibilities for reducing energy consumption, and especially electricity consumption. Space heating should gradually move away from electric heating. Examples are given on measures for improving energy efficiency and problems with financing such measures should be studied

DTU international energy report 2013. Energy storage options for future sustainable energy systems

Energy Technology Data Exchange (ETDEWEB)

Hvidtfeldt Larsen, H.; Soenderberg Petersen, L. (eds.)

2013-11-01

One of the great challenges in the transition to a non-fossil energy system with a high share of fluctuating renewable energy sources such as solar and wind is to align consumption and production in an economically satisfactory manner. Energy storage could provide the necessary balancing power to make this possible. This energy report addresses energy storage from a broad perspective: It analyses smaller stores that can be used locally in for example heat storage in the individual home or vehicle, such as electric cars or hydrogen cars. The report also addresses decentralized storage as flywheels and batteries linked to decentralized energy systems. In addition it addresses large central storages as pumped hydro storage and compressed air energy storage and analyse this in connection with international transmission and trading over long distances. The report addresses electrical storage, thermal storage and other forms of energy storage, for example conversion of biomass to liquid fuel and conversion of solar energy directly into hydrogen, as well as storage in transmission, grid storage etc. Finally, the report covers research, innovation and the future prospects and addresses the societal challenges and benefits of the use of energy storage. (Author)

Power Systems Integration Laboratory | Energy Systems Integration Facility

Science.gov (United States)

| NREL Power Systems Integration Laboratory Power Systems Integration Laboratory Research in the Energy System Integration Facility's Power Systems Integration Laboratory focuses on the microgrid applications. Photo of engineers testing an inverter in the Power Systems Integration Laboratory

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)

Fusion in the energy system

DEFF Research Database (Denmark)

Fusion energy is the fundamental energy source of the Universe, as the energy of the Sun and the stars are produced by fusion of e.g. hydrogen to helium. Fusion energy research is a strongly international endeavor aiming at realizing fusion energy production in power plants on Earth. Reaching...... of integration into the future electricity system and socio-economic studies of fusion energy will be presented, referring to the programme of Socio-Economic Research on Fusion (SERF) under the European Fusion Energy Agreement (EFDA)....

Energy Innovation Systems Indicator Report 2016

DEFF Research Database (Denmark)

Borup, Mads; Klitkou, Antje; Iversen, Eric

This report collates a set of indicators, figures and tables for the energy innovation system in Denmark. Emphasis is on renewable energy and other technologies for moving towards sustainability. The purpose is to provide an overview of indicators available for illuminating dynamics and character...... in “EIS – Strategic research alliance for Energy Innovation Systems and their dynamics – Denmark in global competition”. EIS is funded by the Danish Council for Strategic Research (Innovation Fund Denmark) and by the involved research organisations.......This report collates a set of indicators, figures and tables for the energy innovation system in Denmark. Emphasis is on renewable energy and other technologies for moving towards sustainability. The purpose is to provide an overview of indicators available for illuminating dynamics...... and characteristics of energy innovation systems and to the extent possible offer figures of the developments in the individual indicators. The report is an update of a report published in 2012. Graphs and numbers are updated with the most recent data available. The text is updated where needed in connection...

Fiscal 1974 Sunshine Project result report. Research on solar energy utilization systems (total system); 1974 nendo taiyo energy riyo system chosa kenkyu seika hokokusho. Total system

Energy Technology Data Exchange (ETDEWEB)

NONE

1975-03-01

The current most important solar energy utilization fields are solar energy power generation (solar heat and photovoltaic power generation), and solar heat cooling and heating. A solar heat power system collects or stores solar thermal energy as energy source of power systems, and converts it to electric power through heat exchange systems. To establish such system, not only R and D on a collector, absorption capsule, storage unit and heat transfer unit, but also complete study on an optimum system configuration and environmental impact are necessary. A photovoltaic power system converts solar energy to electric power directly by photoelectric conversion device such solar cell. Except specific local uses, drastic cost reduction and improvement of a conversion efficiency (at present 12-15%) and life (several years) are necessary for solar cells. Although a lot of solar heat cooling and heating systems is in practical use in Japan, for its further diffusion an important research task is development of heat collector excellent in efficiency, cost, life and maintainability. (NEDO)

Five paradox on energy system management

International Nuclear Information System (INIS)

Frisch, J.R.

1995-01-01

Five paradox are detailed on energy management: internationalization of energy questions but always regional management is present, short term problems must be solved but without forgetting long term problems in environment, the third paradox is : we have time but we are in a hurry, we have reserves but ten, twenty or thirty years are necessary to adapt our energy system; the fourth paradox is : we cannot manage energy by managing only energy, for example : finances system development and environment importance. The last and fifth paradox is : the market, yes, but state too, as regulative force

Analysis of integrated energy systems

International Nuclear Information System (INIS)

Matsuhashi, Takaharu; Kaya, Yoichi; Komiyama, Hiroshi; Hayashi, Taketo; Yasukawa, Shigeru.

1988-01-01

World attention is now attracted to the concept of Novel Horizontally Integrated Energy System (NHIES). In NHIES, all fossil fuels are fist converted into CO and H 2 . Potential environmental contaminants such as sulfur are removed during this process. CO turbines are mainly used to generate electric power. Combustion is performed in pure oxygen produced through air separation, making it possible to completely prevent the formation of thermal NOx. Thus, NHIES would release very little amount of such substances that would contribute to acid rain. In this system, the intermediate energy sources of CO, H 2 and O 2 are integrated horizontally. They are combined appropriately to produce a specific form of final energy source. The integration of intermediate energy sources can provide a wide variety of final energy sources, allowing any type of fossil fuel to serve as an alternative to other types of fossil fuel. Another feature of NHIES is the positive use of nuclear fuel to reduce the formation of CO 2 . Studies are under way in Japan to develop a new concept of integrated energy system. These studies are especially aimed at decreased overall efficiency and introduction of new liquid fuels that are high in conversion efficiency. Considerations are made on the final form of energy source, robust control, acid fallout, and CO 2 reduction. (Nogami, K.)

Energy Management Control Systems: Tools for Energy Savings and Environmental Protection

Science.gov (United States)

Zsebik, Albin; Zala, Laszlo F.

2002-01-01

The change in the price of energy has encouraged the increase of energy efficiency. This report will discuss a tool to promote energy efficiency in intelligent buildings, energy management control systems (EMCS). In addition to the online control of energy production, supply, and consumption, the function of the EMCS is to support short- and long-term planning of the system operation as well as to collect, store, and regularly evaluate operation data. The strategies behind planning and implementing the EMCS as well as the manipulating the resulting data are discussed in this report.

Synergies in the Asian energy system: Climate change, energy security, energy access and air pollution

International Nuclear Information System (INIS)

Vliet, Oscar van; Krey, Volker; McCollum, David; Pachauri, Shonali; Nagai, Yu; Rao, Shilpa; Riahi, Keywan

2012-01-01

We use the MESSAGE model to examine multiple dimensions of sustainable development for three Asian regions in a set of scenarios developed for the Asian Modelling Exercise. Using climate change mitigation as a starting point for the analysis, we focus on the interaction of climate and energy with technology choice, energy security, energy access, and air pollution, which often have higher policy priority than climate change. Stringent climate policies drive the future energy supply in Asia from being dominated by coal and oil to a more diversified system based mostly on natural gas, coal with CCS, nuclear and renewable energy. The increase in diversity helps to improve the energy security of individual countries and regions. Combining air pollution control policies and universal energy access policies with climate policy can further help to reduce both outdoor and indoor air pollution related health impacts. Investments into the energy system must double by 2030 to achieve stringent climate goals, but are largely offset by lower costs for O and M and air pollution abatement. Strong focus on end-use efficiency also helps lowering overall total costs and allows for limiting or excluding supply side technologies from the mitigation portfolio. Costs of additional energy access policies and measures are a small fraction of total energy system costs. - Highlights: ► Half of added investments in energy offset by lower costs for O and M and air pollution. ► Costs for achieving universal energy access much smaller than energy system costs. ► Combined emissions and access policies further reduce air pollution impacts on health. ► Strong focus on end-use efficiency allows for more flexibility on energy sources. ► Stringent climate policy can improve energy security of Asian regions.

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)

Assessing reliability in energy supply systems

International Nuclear Information System (INIS)

McCarthy, Ryan W.; Ogden, Joan M.; Sperling, Daniel

2007-01-01

Reliability has always been a concern in the energy sector, but concerns are escalating as energy demand increases and the political stability of many energy supply regions becomes more questionable. But how does one define and measure reliability? We introduce a method to assess reliability in energy supply systems in terms of adequacy and security. It derives from reliability assessment frameworks developed for the electricity sector, which are extended to include qualitative considerations and to be applicable to new energy systems by incorporating decision-making processes based on expert opinion and multi-attribute utility theory. The method presented here is flexible and can be applied to any energy system. To illustrate its use, we apply the method to two hydrogen pathways: (1) centralized steam reforming of imported liquefied natural gas with pipeline distribution of hydrogen, and (2) on-site electrolysis of water using renewable electricity produced independently from the electricity grid

Energy Systems Integration: A Convergence of Ideas

Energy Technology Data Exchange (ETDEWEB)

Kroposki, B.; Garrett, B.; MacMillan, S.; Rice, B.; Komomua, C.; O' Malley, M.; Zimmerle, D.

2012-07-01

Energy systems integration (ESI) enables the effective analysis, design, and control of these interactions and interdependencies along technical, economic, regulatory, and social dimensions. By focusing on the optimization of energy from all systems, across all pathways, and at all scales, we can better understand and make use of the co-benefits that result to increase reliability and performance, reduce cost, and minimize environmental impacts. This white paper discusses systems integration and the research in new control architectures that are optimized at smaller scales but can be aggregated to optimize energy systems at any scale and would allow replicable energy solutions across boundaries of existing and new energy pathways.

Integrated Nuclear-Renewable Energy Systems: Foundational Workshop Report

International Nuclear Information System (INIS)

2014-01-01

The U.S. Department of Energy (DOE) recognizes the need to transform the energy infrastructure of the U.S. and elsewhere to systems that can drastically reduce environmental impacts in an efficient and economically viable manner while utilizing both hydrocarbon resources and clean energy generation sources. Thus, DOE is supporting research and development that could lead to more efficient utilization of clean energy generation sources, including renewable and nuclear options. A concept being advanced by the DOE Offices of Nuclear Energy (NE) and Energy Efficiency and Renewable Energy (EERE) is tighter coupling of nuclear and renewable energy sources in a manner that produces new energy currency for the combined electricity grid, industrial manufacturing, and the transportation energy sectors. This integration concept has been referred to as a ''hybrid system'' that is capable of providing the right type of energy, at the right time, in the right place. At the direction of DOE-NE and DOE-EERE leadership, project leads at Idaho National Laboratory (INL), National Renewable Energy Laboratory (NREL) and Massachusetts Institute of Technology (MIT) have identified and engaged stakeholders in discussing integrated energy systems that would optimize renewable and nuclear energy integration on a region-by-region basis. Subsequent work will entail conduct of technical, economic, environmental and socio-political evaluations of the leading integrated system options based on a set of criteria established with stakeholder input. The Foundational Workshop for Integrated Nuclear - Renewable Energy Systems was organized around the following objectives: 1. Identify and refine priority region-specific opportunities for integrated nuclear-renewable energy systems in the U.S.; 2. Select Figures of Merit (FOM) to rank and prioritize candidate systems; 3. Discuss enabling technology development needs; 4. Identify analysis requirements, capabilities and gaps to

Calculations of energy consumption in ventilation systems

Energy Technology Data Exchange (ETDEWEB)

Kreslins, Andris; Ramata, Anna [Riga Technical University (Latvia)], e-mail: kreslins@rbf.rtu.lv, email: Anna.Ramata@rtu.lv

2011-07-01

Energy cost is an important economic factor in the food industry production process. With the rising price of energy, a reduction in energy consumption would greatly impact production and the end product. The aim of this study was to develop a methodology for optimizing energy consumption. A comparison between a traditional ventilation system and a mechanical system was carried out; the necessary enthalpy for heating the air supply and thermal energy consumption were calculated and compared for both systems during the heating season, from October to April, using climatological data for Latvia. Results showed that energy savings of 46% to 87% can be achieved by applying the methodology in the design of industrial buildings; in addition, a well-designed ventilation system increases the workers' productivity. This study presented a methodology which can optimize energy consumption in the food industry sector.

Analytical investigation of low temperature lift energy conversion systems with renewable energy source

International Nuclear Information System (INIS)

Lee, Hoseong; Hwang, Yunho; Radermacher, Reinhard

2014-01-01

The efficiency of the renewable energy powered energy conversion system is typically low due to its moderate heat source temperature. Therefore, improving its energy efficiency is essential. In this study, the performance of the energy conversion system with renewable energy source was theoretically investigated in order to explore its design aspect. For this purpose, a computer model of n-stage low temperature lift energy conversion (LTLEC) system was developed. The results showed that under given operating conditions such as temperatures and mass flow rates of heat source and heat sink fluids the unit power generation of the system increased with the number of stage, and it became saturated when the number of staging reached four. Investigation of several possible working fluids for the optimum stage LTLEC system revealed that ethanol could be an alternative to ammonia. The heat exchanger effectiveness is a critical factor on the system performance. The power generation was increased by 7.83% for the evaporator and 9.94% for the condenser with 10% increase of heat exchanger effectiveness. When these low temperature source fluids are applied to the LTLEC system, the heat exchanger performance would be very critical and it has to be designed accordingly. - Highlights: •Energy conversion system with renewable energy is analytically investigated. •A model of multi-stage low temperature lift energy conversion systems was developed. •The system performance increases as the stage number is increased. •The unit power generation is increased with increase of HX effectiveness. •Ethanol is found to be a good alternative to ammonia

Developing a Model of the Irish Energy-System

DEFF Research Database (Denmark)

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

2009-01-01

to create the model as it accounts for all sectors that need to be considered for integrating large penetrations of renewable energy: the electricity, heat and transport sectors. Before various alternative energy-systems could be investigated for Ireland, a reference model of the existing system needed...... is a vital step due to the scale of the change required for large-scale renewable penetrations. In this paper, a model of the Irish energy system is created to identify how Ireland can transform from a fossil-fuel to a renewable energy-system. The energy-systems-analysis tool, EnergyPLAN, was chosen...... to be created. This paper focuses on the construction of this reference model, in terms of the data gathered, the assumptions made and the accuracy achieved. In future work, this model will be used to investigate alternative energy-systems for Ireland, with the aim to determine the most effective energy system...

Web based system for renewable energy sources assessment

International Nuclear Information System (INIS)

Shtrakov, Stanko; Ivanov, Lachezar South

2011-01-01

The RES A ssess software is developed to assist in the preliminary assessment of potential renewable energy projects. The first release includes water pumping solar systems, passive solar systems, wind, and geothermal energy and biomass. The program guides the users in the design of their systems, by providing initial estimates. By changing the system’s parameters, users are able to quickly screen an effective technology and system size depending on load, climatic conditions, and season of use. This paper describes scope of models (radiation, wind, geothermal, heat transfer) used to predict energy production from energy resource systems, climatic variables and system parameters and software technology for realising the project. Keywords: Energy projects, Renewable energy, Web system

Smart Cities and National Energy Systems

DEFF Research Database (Denmark)

Thellufsen, Jakob Zinck

Energy system analysis follows two tracks, either through plans for future transitions of national energy systems, or local development of smart cities and regions. These two tracks seldom overlap. National plans neglect the local implementation of intermittent renewable technology and use of local...... resources, and smart cities and local development do not relate to national targets and fail to evaluate sub-optimization. Thus, there is a need for approaches that help researchers creating links between country analyses and local energy system transitions. This paper investigates the effects...... of such an approach, by investigating Western Denmark. By splitting Western Denmark into regions, it is possible to create individual energy systems for each region. Through interconnection, these regions can exchange electricity with each other. This enables analyses of interaction between smart cities and national...

Nuclear Hybrid Energy Systems: Challenges and Opportunities

Energy Technology Data Exchange (ETDEWEB)

P. Sabharwall; S.B. Sitton; S.J. Yoon; C. Stoots

2014-07-01

With growing demand of energy and costs of the fossil fuels, coupled with the environmental concerns have resulted in an increased interest in alternative energy sources. Nuclear hybrid energy systems (NHES) are being considered which incorporates renewable energy sources such as solar and wind energy combined with nuclear reactor and energy storage to meet the peak hours demand imposed on the grid, along with providing process heat for other potential industrial applications. This concept could potentially satisfy various energy demands and improve reliability, robustness and resilience for the entire system as a whole, along with economic and net efficiency gains. This paper provides a brief understanding of potential NHES system and architecture along with the challenges

The application of a Grey Markov Model to forecasting annual maximum water levels at hydrological stations

Science.gov (United States)

Dong, Sheng; Chi, Kun; Zhang, Qiyi; Zhang, Xiangdong

2012-03-01

Compared with traditional real-time forecasting, this paper proposes a Grey Markov Model (GMM) to forecast the maximum water levels at hydrological stations in the estuary area. The GMM combines the Grey System and Markov theory into a higher precision model. The GMM takes advantage of the Grey System to predict the trend values and uses the Markov theory to forecast fluctuation values, and thus gives forecast results involving two aspects of information. The procedure for forecasting annul maximum water levels with the GMM contains five main steps: 1) establish the GM (1, 1) model based on the data series; 2) estimate the trend values; 3) establish a Markov Model based on relative error series; 4) modify the relative errors caused in step 2, and then obtain the relative errors of the second order estimation; 5) compare the results with measured data and estimate the accuracy. The historical water level records (from 1960 to 1992) at Yuqiao Hydrological Station in the estuary area of the Haihe River near Tianjin, China are utilized to calibrate and verify the proposed model according to the above steps. Every 25 years' data are regarded as a hydro-sequence. Eight groups of simulated results show reasonable agreement between the predicted values and the measured data. The GMM is also applied to the 10 other hydrological stations in the same estuary. The forecast results for all of the hydrological stations are good or acceptable. The feasibility and effectiveness of this new forecasting model have been proved in this paper.

Energy and environmental evaluation of tri-generation energy systems

International Nuclear Information System (INIS)

Chicco, G.; Mancarella, P.

2008-01-01

Tri generation facilities manufactured with various technologies represent an important alternative solution for the development more efficient energy systems and low environmental impact. Are described the issues related to modelling and energy and environmental evaluation [it

Achievement report for fiscal 1998 on development of wide-area energy utilization network system. Eco-energy urban system (Research of systematization technology and evaluation technology out of energy system designing technology researches); Koiki energy riyo network system kaihatsu (eko energy toshi system) 1998 nendo seika hokokusho. Energy system sekkei gijutsu no kenkyu no uchi system ka gijutsu hyoka gijutsu no kenkyu

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-03-01

For the realization of urban society respecting enhanced energy efficiency and environmental protection, cities and surrounding industrial facilities are investigated for the development of element technologies involving energy recovery, conversion, transportation, storage, delivery, utilization, etc., and for the compounding of urban energy systems. In the study of the effect of introduction, assumption is made of delivery of heat to an urban heat accumulation district from a plant equivalent to a district air-conditioning system which is covered by the existing technologies. Also assumed are the delivery of exhaust heat to the said plant utilizing eco-energy element technologies and the replacement of existing technologies by eco-energy element technologies. Comparison is established in terms of energy efficiency, environmental protection, and economy, and then it is found that the eco-energy element technologies for the utilization of exhaust heat are in all cases superior to the conventional technologies as far as energy efficiency and environmental protection are concerned. It is found, however, that they are inferior from the economic viewpoint. The energy efficiency technology in heat transportation is superior to the existing technology in energy efficiency and environmental protection but roughly equal to the existing ones in economy. (NEDO)

Strategic energy planning: Modelling and simulating energy market behaviours using system thinking and systems dynamics principles

International Nuclear Information System (INIS)

Papageorgiou, George Nathaniel

2005-01-01

In the face of limited energy reserves and the global warming phenomenon, Europe is undergoing a transition from rapidly depleting fossil fuels to renewable unconventional energy sources. During this transition period, energy shortfalls will occur and energy prices will be increasing in an oscillating manner. As a result of the turbulence and dynamicity that will accompany the transition period, energy analysts need new appropriate methods, techniques and tools in order to develop forecasts for the behaviour of energy markets, which would assist in the long term strategic energy planning and policy analysis. This paper reviews energy market behaviour as related to policy formation, and from a dynamic point of view through the use of ''systems thinking'' and ''system dynamics'' principles, provides a framework for modelling the energy production and consumption process in relation to their environment. Thereby, effective energy planning can be developed via computerised simulation using policy experimentation. In a demonstration model depicted in this paper, it is shown that disasters due to attractive policies can be avoided by using simple computer simulation. (Author)

Design and installation of earth energy systems

Energy Technology Data Exchange (ETDEWEB)

Loggia, S; Adragna, M; Coyle, S; Foley, C; Hawryn, S; Martin, A; McConnell, J [eds.

2002-07-01

This first edition of the Canadian Standards Association (CSA) Standard C448 Series, replaces CSA Standards CAN/CSA-C445-M92 entitled Design and Installation of Earth Energy Heat Pump Systems for Residential and Other Small Buildings, as well as C447-94 entitled Design and Installation of Earth Energy Heat Pump Systems for Commercial and Institutional Buildings. This standard document consists of three parts: (C448.1) Design and installation of earth energy systems for commercial and institutional buildings; (C448.2) Design and installation of earth energy systems for residential and small buildings; and, (C448.3) Design and installation of underground thermal energy storage systems for commercial and institutional buildings. In C448.1, the requirements applicable to any system falling within the scope of the C448 series were included. Alternative requirements for houses and small buildings were added in C448.2. It was noted that either standard may be implemented. The standards applicable to the intentional storage of energy in the earth for later use were presented in C448.3. This latter section includes a brief introduction on underground thermal energy storage (UTES). tabs.

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.

Alternative energy sources or integrated alternative energy systems? Oil as a modern lance of Peleus for the energy transition

International Nuclear Information System (INIS)

Szklo, Alexandre; Schaeffer, Roberto

2006-01-01

In this viewpoint, we discuss the importance of consorting alternative energy sources with oil, and not of opposing them. That is why we introduce the concept of alternative energy systems, which we feel is broader-ranging and more effective than alternative energy sources, as this deals with the actual transformation process of the global energy system. Alternative energy systems integrate oil with other energy sources and pave the way for new systems, which will benefit from what we call the 'virtues of oil'. They produce energy carriers for multi-fuel and multi-product strategies, where flexibility is a key target, allied to other co-benefits, especially those related to the increased use of renewable energy sources. The concept of alternative energy systems can bring a new light to the oil transition era discussion and might also influence energy policies for promoting renewables

Energy-Cost Optimisation in Water-Supply System

OpenAIRE

Farrukh Mahmood; Haider Ali

2013-01-01

Households as well as community water-supply systems for utilisation of underground aquifers are massive consumers of energy. Prevailing energy crisis and focus of the government on demand-side energy policies (i.e., energy conservation) in Pakistan raises need of using energy efficient techniques in almost every aspect of life. This paper analyses performance of community relative to household water-supply system in connection with efficient energy utilisation. Results suggest that total ope...

Integrated Nuclear-Renewable Energy Systems: Foundational Workshop Report

Energy Technology Data Exchange (ETDEWEB)

Bragg-Sitton, Shannon [Idaho National Lab. (INL), Idaho Falls, ID (United States); Boardman, Richard [Idaho National Lab. (INL), Idaho Falls, ID (United States); Ruth, Mark [National Renewable Energy Lab. (NREL), Golden, CO (United States); Zinaman, Owen [National Renewable Energy Lab. (NREL), Golden, CO (United States); Forsberg, Charles [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Collins, John [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2014-08-01

The U.S. Department of Energy (DOE) recognizes the need to transform the energy infrastructure of the U.S. and elsewhere to systems that can drastically reduce environmental impacts in an efficient and economically viable manner while utilizing both hydrocarbon resources and clean energy generation sources. Thus, DOE is supporting research and development that could lead to more efficient utilization of clean energy generation sources, including renewable and nuclear options. A concept being advanced by the DOE Offices of Nuclear Energy (NE) and Energy Efficiency and Renewable Energy (EERE) is tighter coupling of nuclear and renewable energy sources in a manner that produces new energy currency for the combined electricity grid, industrial manufacturing, and the transportation energy sectors. This integration concept has been referred to as a “hybrid system” that is capable of providing the right type of energy, at the right time, in the right place. At the direction of DOE-NE and DOE-EERE leadership, project leads at Idaho National Laboratory (INL), National Renewable Energy Laboratory (NREL) and Massachusetts Institute of Technology (MIT) have identified and engaged stakeholders in discussing integrated energy systems that would optimize renewable and nuclear energy integration on a region-by-region basis. Subsequent work will entail conduct of technical, economic, environmental and socio-political evaluations of the leading integrated system options based on a set of criteria established with stakeholder input. The Foundational Workshop for Integrated Nuclear – Renewable Energy Systems was organized around the following objectives: 1. Identify and refine priority region-specific opportunities for integrated nuclear-renewable energy systems in the U.S.; 2. Select Figures of Merit (FOM) to rank and prioritize candidate systems; 3. Discuss enabling technology development needs; 4. Identify analysis requirements, capabilities and gaps to estimate FOM for

Sourcebook for energy assessment. [Reference Energy Systems for 1972-2020

Energy Technology Data Exchange (ETDEWEB)

Beller, M. (ed.)

1975-12-01

An analytical approach is presented that is broadly applicable to the assessment of energy technologies and policies. Using the Reference Energy System approach, it permits the examination of the economic, environmental, and resource implications resulting from the substitution of one fuel or technology for another. Included as tools for such analyses are the necessary data and methodology, as well as a set of Reference Energy Systems covering the 1972-2020 period to serve as baselines for the perturbation analyses of interest. 46 tables, 25 figures, 71 references.

Global Renewable Energy-Based Electricity Generation and Smart Grid System for Energy Security

Science.gov (United States)

Islam, M. A.; Hasanuzzaman, M.; Rahim, N. A.; Nahar, A.; Hosenuzzaman, M.

2014-01-01

Energy is an indispensable factor for the economic growth and development of a country. Energy consumption is rapidly increasing worldwide. To fulfill this energy demand, alternative energy sources and efficient utilization are being explored. Various sources of renewable energy and their efficient utilization are comprehensively reviewed and presented in this paper. Also the trend in research and development for the technological advancement of energy utilization and smart grid system for future energy security is presented. Results show that renewable energy resources are becoming more prevalent as more electricity generation becomes necessary and could provide half of the total energy demands by 2050. To satisfy the future energy demand, the smart grid system can be used as an efficient system for energy security. The smart grid also delivers significant environmental benefits by conservation and renewable generation integration. PMID:25243201

Global renewable energy-based electricity generation and smart grid system for energy security.

Science.gov (United States)

Islam, M A; Hasanuzzaman, M; Rahim, N A; Nahar, A; Hosenuzzaman, M

2014-01-01

Energy is an indispensable factor for the economic growth and development of a country. Energy consumption is rapidly increasing worldwide. To fulfill this energy demand, alternative energy sources and efficient utilization are being explored. Various sources of renewable energy and their efficient utilization are comprehensively reviewed and presented in this paper. Also the trend in research and development for the technological advancement of energy utilization and smart grid system for future energy security is presented. Results show that renewable energy resources are becoming more prevalent as more electricity generation becomes necessary and could provide half of the total energy demands by 2050. To satisfy the future energy demand, the smart grid system can be used as an efficient system for energy security. The smart grid also delivers significant environmental benefits by conservation and renewable generation integration.

Global Renewable Energy-Based Electricity Generation and Smart Grid System for Energy Security

Directory of Open Access Journals (Sweden)

M. A. Islam

2014-01-01

Full Text Available Energy is an indispensable factor for the economic growth and development of a country. Energy consumption is rapidly increasing worldwide. To fulfill this energy demand, alternative energy sources and efficient utilization are being explored. Various sources of renewable energy and their efficient utilization are comprehensively reviewed and presented in this paper. Also the trend in research and development for the technological advancement of energy utilization and smart grid system for future energy security is presented. Results show that renewable energy resources are becoming more prevalent as more electricity generation becomes necessary and could provide half of the total energy demands by 2050. To satisfy the future energy demand, the smart grid system can be used as an efficient system for energy security. The smart grid also delivers significant environmental benefits by conservation and renewable generation integration.

24 CFR 203.18a - Solar energy system.

Science.gov (United States)

2010-04-01

... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Solar energy system. 203.18a... § 203.18a Solar energy system. (a) The dollar limitation provided in § 203.18(a) may be increased by up... to the installation of a solar energy system. (b) Solar energy system is defined as any addition...

A generic framework for the description and analysis of energy security in an energy system

International Nuclear Information System (INIS)

Hughes, Larry

2012-01-01

While many energy security indicators and models have been developed for specific jurisdictions or types of energy, few can be considered sufficiently generic to be applicable to any energy system. This paper presents a framework that attempts to meet this objective by combining the International Energy Agency's definition of energy security with structured systems analysis techniques to create three energy security indicators and a process-flow energy systems model. The framework is applicable to those energy systems which can be described in terms of processes converting or transporting flows of energy to meet the energy–demand flows from downstream processes. Each process affects the environment and is subject to jurisdictional policies. The framework can be employed to capture the evolution of energy security in an energy system by analyzing the results of indicator-specific metrics applied to the energy, demand, and environment flows associated with the system's constituent processes. Energy security policies are treated as flows to processes and classified into one of three actions affecting the process's energy demand or the process or its energy input, or both; the outcome is determined by monitoring changes to the indicators. The paper includes a detailed example of an application of the framework. - Highlights: ► The IEA's definition of energy security is parsed into three energy security indicators: availability, affordability, and acceptability. ► Data flow diagrams and other systems analysis tools can represent an energy system and its processes, flows, and chains. ► Indicator-specific metrics applied to a process's flow determine the state of energy security in an energy system, an energy chain, or process. ► Energy policy is considered as a flow and policy outcomes are obtained by measuring flows with indicator-specific metrics. ► The framework is applicable to most jurisdictions and energy types.

Balmorel open source energy system model

DEFF Research Database (Denmark)

Wiese, Frauke; Bramstoft, Rasmus; Koduvere, Hardi

2018-01-01

As the world progresses towards a cleaner energy future with more variable renewable energy sources, energy system models are required to deal with new challenges. This article describes design, development and applications of the open source energy system model Balmorel, which is a result...... of a long and fruitful cooperation between public and private institutions within energy system research and analysis. The purpose of the article is to explain the modelling approach, to highlight strengths and challenges of the chosen approach, to create awareness about the possible applications...... of Balmorel as well as to inspire to new model developments and encourage new users to join the community. Some of the key strengths of the model are the flexible handling of the time and space dimensions and the combination of operation and investment optimisation. Its open source character enables diverse...

Solar Energy Systems for Ohioan Residential Homeowners

Science.gov (United States)

Luckett, Rickey D.

Dwindling nonrenewable energy resources and rising energy costs have forced the United States to develop alternative renewable energy sources. The United States' solar energy industry has seen an upsurge in recent years, and photovoltaic holds considerable promise as a renewable energy technology. The purpose of this case study was to explore homeowner's awareness of the benefits of solar energy. Disruptive-innovation theory was used to explore marketing strategies for conveying information to homeowners about access to new solar energy products and services. Twenty residential homeowners were interviewed face-to-face to explore (a) perceived benefits of solar energy in their county in Ohio, and (b) perceptions on the rationale behind the marketing strategy of solar energy systems sold for residential use. The study findings used inductive analyses and coding interpretation to explore the participants' responses that revealed 3 themes: the existence of environmental benefits for using solar energy systems, the expensive cost of equipment associated with government incentives, and the lack of marketing information that is available for consumer use. The implications for positive social change include the potential to enable corporate leaders, small business owners, and entrepreneurs to develop marketing strategies for renewable energy systems. These strategies may promote use of solar energy systems as a clean, renewable, and affordable alternative electricity energy source for the 21st century.

Efficiency Evaluation of Energy Systems

CERN Document Server

Kanoğlu, Mehmet; Dinçer, İbrahim

2012-01-01

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

Energy Storage Systems

Science.gov (United States)

Elliott, David

2017-07-01

As renewable energy use expands there will be a need to develop ways to balance its variability. Storage is one of the options. Presently the main emphasis is for systems storing electrical power in advanced batteries (many of them derivatives of parallel developments in the electric vehicle field), as well as via liquid air storage, compressed air storage, super-capacitors and flywheels, and, the leader so far, pumped hydro reservoirs. In addition, new systems are emerging for hydrogen generation and storage, feeding fuel cell power production. Heat (and cold) is also a storage medium and some systems exploit thermal effects as part of wider energy management activity. Some of the more exotic ones even try to use gravity on a large scale. This short book looks at all the options, their potentials and their limits. There are no clear winners, with some being suited to short-term balancing and others to longer-term storage. The eventual mix adopted will be shaped by the pattern of development of other balancing measures, including smart-grid demand management and super-grid imports and exports.

Energy policies and renewable energy systems monitoring

Energy Technology Data Exchange (ETDEWEB)

Di Nisio, Attilio; Savino, Mario; Spadavecchia, Maurizio [Electrical and Electronic Measurements Laboratory, Dept. of Electrical and Electronic Engineering - Politecnico di Bari, Bari (Italy)], e-mails: dinisio@misure.poliba.it, savino@misure.poliba.it, spadavecchia@misure.poliba.it

2011-07-01

Full text: The global energy crisis is forcing every country worldwide to review its policies on energy. The environmental disaster at Japan's Fukushima Daiichi nuclear power plant has accelerated this process. Many people around the world are citing the disaster as evidence that nuclear power would endanger the survival of mankind on earth and should be banned. Today we need to focus more substantially on energy saving, especially using smart devices with low power consumption. We have also to review the approach to the exploitation of energy and move from a philosophy 'from the ground to the subsurface' to another 'from the earth to the sun'. This paper highlights the increasing importance of solar power in meeting energy needs while achieving security of supply and minimising carbon dioxide (CO{sub 2}) emissions. It deals also with the development of solar power plants, which require a supervisory control system that improves their efficiency and reliability. (author)

A Fuzzy-Based Building Energy Management System for Energy Efficiency

Directory of Open Access Journals (Sweden)

José L. Hernández

2018-01-01

Full Text Available Information and communication technologies (ICT offer immense potential to improve the energetic performance of buildings. Additionally, common building control systems are typically based on simple decision-making tools, which possess the ability to obtain controllable parameters for indoor temperatures. Nevertheless, the accuracy of such common building control systems is improvable with the integration of advanced decision-making techniques embedded into software and energy management tools. This paper presents the design of a building energy management system (BEMS, which is currently under development, and that makes use of artificial intelligence for the automated decision-making process required for optimal comfort of occupants and utilization of renewables for achieving energy-efficiency in buildings. The research falls under the scope of the H2020 project BREASER which implements fuzzy logic with the aim of governing the energy resources of a school in Turkey, which has been renovated with a ventilated façade with integrated renewable energy sources (RES. The BRESAER BEMS includes prediction techniques that increase the accuracy of common BEMS tools, and subsequent energy savings, while ensuring the indoor thermal comfort of the building occupants. In particular, weather forecast and simulation strategies are integrated into the functionalities of the overall system. By collecting the aforementioned information, the BEMS makes decisions according to a well-established selection of key performance indicators (KPIs with the objective of providing a quantitative comparable value to determine new actuation parameters.

Determinants of Renewable Energy Innovation: Environmental Policies vs. Market Regulation

International Nuclear Information System (INIS)

Vona, Francesco; Nesta, Lionel; Nicolli, Francesco

2012-02-01

This paper carries out a comprehensive analysis of renewable energy innovations considering four mechanisms suggested by innovation models: 1. policy-inducement; 2. market structure; 3. demand and social cohesion- mainly proxied by income inequality; 4. characteristics of country knowledge base. For OECD countries and years 1970-2005, we build a unique dataset containing time-varying information on quality-adjusted patent production in renewable energy, the latter being a function of environmental policies, green R and D, entry barriers, knowledge stock, knowledge diversity and income inequality. We develop count data models using the Generalized Method of Moments (GMM) to account for endogeneity of policy support. Our synthetic policy index positively affects innovations especially in countries with deregulated energy markets and low entry barriers. The effect of entry barriers and inequality is negative and of similar magnitude as that of policy. Product market liberalization positively affects green patent generation, especially so when ambitious policies are adopted, when the initial level of public R and D expenditures and when the initial share of distributed energy generation is high. Our results are robust to alternative specifications, to the inclusion of technology-specific effects and to the use of quality-adjusted patents as dependent variables. In the latter case, the estimated effect of lowering entry barriers and of knowledge diversity almost double on citation count relatively to patent count. (authors)

Proceedings of the 13th Energy System and Economy Conference; Dai 13 kai energy system keizai conference koen ronbunshu

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-01-30

The Energy System and Economy Conference was held in Tokyo on January 30 and 31, 1997, including 80 papers made public, keynote speeches having a theme of the international situation in the climate change issue and the Japanese condition, and panel discussions. In the special session on the global environmental problem, speeches were given on CO2 emission/reduction, CO2 recovery/fixation, environmental policy, comprehensive analyses, etc. In the electric power economy section, reports were made on effects of load characteristics of the power system on the effectiveness of power supply, the free electric power market and DSM (demand-side management), etc. As to the energy system, reported were a study on increasing efficiency of the hydrogen use regional heat supply system, samples of the hydrogen energy system for local core cities, etc. Relating to the energy technology, a paper on a proposal of solid phase heat engines using shape memory alloys and others were read. Papers were more added on urban and commercial/residential energy, natural energy, traffic, energy economy, etc.

ADVANCES IN ZERO ENERGY TRANSPORTATION SYSTEMS

OpenAIRE

Ahmad, Othman

2017-01-01

Hyperloop mass transportation systems are activelydeveloped at the moment. They represent the forefront development of the ZeroEnergy Transportation systems where air drag is minimized by travelling in avacuum and friction is reduced by non-contact bearings. Hyperloop supportersare confident that the cost of their transportation systems would be lowcompared to existing transportation systems because of the low loss andtherefore low energy consumption as well as other cost-saving techniquesdoc...

TOP-Energy - toolkit for optimization of industrial energy systems; TOP-Energy - Softwaregestuetzte Analyse und Optimierung industrieller Energieversorgungssysteme

Energy Technology Data Exchange (ETDEWEB)

Augenstein, E.; Kuperjans, I. [RWTH Aachen (Germany); Wrobel, G. [Gesellschaft zur Foerderung angewandter Informatik e.V. (GFal), Berlin (Germany); Gruezenich, D.

2004-07-01

The contribution presents the software package 'TOP-Energy' which supports energy consultants in their analysis and optimisation of industrial energy systems and is a tool for development and assessment of measures for reducing the energy cost and the consumption of energy resources. In particular, it supports data acquisition, evaluation, and presentation of results of routine work; it offers simulations of complel processes and systems as well as tools like integrated project management. TOP-Energy consists of several modules linked by a common framework. The framework is for data management, module integration and control, and offers a user interface in the form of adaptable editors, dialogues and menus. Power supply systems of industrial works can be modelled with all their components. The key module of Top-energy is a simulator for systems designed, with variable temporal load curves and other boundary conditions. (orig.)

Energy pay-back time of photovoltaic energy systems: present status and prospects

NARCIS (Netherlands)

Alsema, E.A.; Frankl, P.; Kato, K.

1998-01-01

In this paper we investigate the energy requirements of PV modules and systems and calculate the Energy Pay-Back Time for three major PV applications. Based on a review of past energy analysis studies we explain the main sources of differences and establish a "best estimate" for key system

Renewable Energy Systems: Technology Overview and Perspectives

DEFF Research Database (Denmark)

Blaabjerg, Frede; Ionel, Dan M.; Yang, Yongheng

2017-01-01

In this chapter, essential statistics demonstrating the increasing role of renewable energy generation are first discussed. A state-of-the-art review section covers the fundamentals of wind turbine and photovoltaic (PV) systems. Schematic diagrams illustrating the main components and system topol......, including PV and concentrating solar power; wave energy; fuel cells; and storage with batteries and hydrogen, respectively. Recommended further readings on topics of electric power engineering for renewable energy are included in the final section.......In this chapter, essential statistics demonstrating the increasing role of renewable energy generation are first discussed. A state-of-the-art review section covers the fundamentals of wind turbine and photovoltaic (PV) systems. Schematic diagrams illustrating the main components and system...... topologies are included. Also, the increasing role of power electronics is explained as an enabler for renewable energy integration and for future power systems and smart grids. Recent examples of research and development, including new devices and system installations for utility power plants...

Environmental health risk assessment: Energy systems

International Nuclear Information System (INIS)

Krewski, D.; Somers, E.; Winthrop, S.O.

1984-01-01

Most industrialized nations have come to rely on a variety of systems for energy production, both of a conventional and non-conventional nature. In the paper, the spectrum of energy systems currently in use in Canada is outlined along with their potential health risks. Several examples of environmental health studies involving both outdoor and indoor air pollution related to energy production in Canada are reported. The limitations of current technologies for assessing health risks are discussed and possible approaches to managing energy related health risks are indicated. (author)

Restructuring energy systems for sustainability? Energy transition policy in the Netherlands

International Nuclear Information System (INIS)

Kern, Florian; Smith, Adrian

2008-01-01

Increasingly, researchers and policy makers are confronting the challenge of restructuring energy systems into more sustainable forms. A 'transition management' model, and its adoption in the Netherlands, is attracting attention. Starting from the socio-technical multi-level theory that informs 'transition management', we analyse the 'energy transition' project carried out by the Dutch Ministry of Economic Affairs. Despite considerable achievements, their approach risks capture by the incumbent energy regime, thereby undermining original policy ambitions for structural innovation of the energy system. This experience presents generic dilemmas for transitions approaches

Energy technology sources, systems and frontier conversion

CERN Document Server

Ohta, Tokio

1994-01-01

This book provides a concise and technical overview of energy technology: the sources of energy, energy systems and frontier conversion. As well as serving as a basic reference book for professional scientists and students of energy, it is intended for scientists and policy makers in other disciplines (including practising engineers, biologists, physicists, economists and managers in energy related industries) who need an up-to-date and authoritative guide to the field of energy technology.Energy systems and their elemental technologies are introduced and evaluated from the view point

Soft computing in green and renewable energy systems

Energy Technology Data Exchange (ETDEWEB)

Gopalakrishnan, Kasthurirangan [Iowa State Univ., Ames, IA (United States). Iowa Bioeconomy Inst.; US Department of Energy, Ames, IA (United States). Ames Lab; Kalogirou, Soteris [Cyprus Univ. of Technology, Limassol (Cyprus). Dept. of Mechanical Engineering and Materials Sciences and Engineering; Khaitan, Siddhartha Kumar (eds.) [Iowa State Univ. of Science and Technology, Ames, IA (United States). Dept. of Electrical Engineering and Computer Engineering

2011-07-01

Soft Computing in Green and Renewable Energy Systems provides a practical introduction to the application of soft computing techniques and hybrid intelligent systems for designing, modeling, characterizing, optimizing, forecasting, and performance prediction of green and renewable energy systems. Research is proceeding at jet speed on renewable energy (energy derived from natural resources such as sunlight, wind, tides, rain, geothermal heat, biomass, hydrogen, etc.) as policy makers, researchers, economists, and world agencies have joined forces in finding alternative sustainable energy solutions to current critical environmental, economic, and social issues. The innovative models, environmentally benign processes, data analytics, etc. employed in renewable energy systems are computationally-intensive, non-linear and complex as well as involve a high degree of uncertainty. Soft computing technologies, such as fuzzy sets and systems, neural science and systems, evolutionary algorithms and genetic programming, and machine learning, are ideal in handling the noise, imprecision, and uncertainty in the data, and yet achieve robust, low-cost solutions. As a result, intelligent and soft computing paradigms are finding increasing applications in the study of renewable energy systems. Researchers, practitioners, undergraduate and graduate students engaged in the study of renewable energy systems will find this book very useful. (orig.)

Energy and environmental management information systems

Energy Technology Data Exchange (ETDEWEB)

Martin, P.K. (Energy Auditing Agency Ltd., Milton Keynes (United Kingdom))

1993-01-01

The threat of global warming, environmental instability and the possible use of green or carbon taxes on fossil fuels has increased the need for energy efficiency. Energy Conservation is now recognised as one of the easiest and most cost-effective ways of limiting or reducing CO[sub 2] emissions. Large UK companies are now assessing how much CO[sub 2] they dissipate to the environment and reviewing strategies to reduce this either in response to consumer demand or as a corporate policy decision. Computer-based information systems already exist to monitor and report on fluctuations in energy consumption. These are called Monitoring and Targeting (M and T) systems. This paper explains what M and T systems are and how they are being extended to cover reporting on corporate fuel-based CO[sub 2] emissions to help provide an integrated energy and environmental-management information system. (author).

Decentralized Energy from Waste Systems

Directory of Open Access Journals (Sweden)

Blanca Antizar-Ladislao

2010-01-01

Full Text Available In the last five years or so, biofuels have been given notable consideration worldwide as an alternative to fossil fuels, due to their potential to reduce greenhouse gas emissions by partial replacement of oil as a transport fuel. The production of biofuels using a sustainable approach, should consider local production of biofuels, obtained from local feedstocks and adapted to the socio-economical and environmental characteristics of the particular region where they are developed. Thus, decentralized energy from waste systems will exploit local biomass to optimize their production and consumption. Waste streams such as agricultural and wood residues, municipal solid waste, vegetable oils, and algae residues can all be integrated in energy from waste systems. An integral optimization of decentralized energy from waste systems should not be based on the optimization of each single process, but the overall optimization of the whole process. This is by obtaining optimal energy and environmental benefits, as well as collateral beneficial co-products such as soil fertilizers which will result in a higher food crop production and carbon dioxide fixation which will abate climate change.

Decentralized energy from waste systems

International Nuclear Information System (INIS)

Antizar-Ladislao, B.; Turrion-Gomez, J. L.

2010-01-01

In the last five years or so, biofuels have been given notable consideration worldwide as an alternative to fossil fuels, due to their potential to reduce greenhouse gas emissions by partial replacement of oil as a transport fuel. The production of biofuels using a sustainable approach, should consider local production of biofuels, obtained from local feedstocks and adapted to the socio-economical and environmental characteristics of the particular region where they are developed. Thus, decentralized energy from waste systems will exploit local biomass to optimize their production and consumption. Waste streams such as agricultural and wood residues, municipal solid waste, vegetable oils, and algae residues can all be integrated in energy from waste systems. An integral optimization of decentralized energy from waste systems should not be based on the optimization of each single process, but the overall optimization of the whole process. This is by obtaining optimal energy and environmental benefits, as well as collateral beneficial co-products such as soil fertilizers which will result in a higher food crop production and carbon dioxide fixation which will abate climate change. (author)

Nuclear technologies for local energy systems

International Nuclear Information System (INIS)

McDonnell, F.N.; Lynch, G.F.

1990-03-01

If nuclear energy is to realize its full potential as a safe and cost-effective alternative to fossil fuels, applications beyond those that are currently being serviced by large, central nuclear power stations must be identified and appropriate reactors developed. The Canadian program on reactor systems for local energy supply is at the forefront of these developments. This program emphasizes design simplicity, low power density and fuel rating, reliance on natural processes, passive systems, and reduced reliance on operator action. The first product, the SLOWPOKE Energy System, is a 10 MW heat source specifically designed to provide hot water to satisfy the needs of local heating systems for building complexes, institutions and municipal district heating systems. A demonstration heating reactor has been constructed at the Whiteshell Nuclear Research Establishment in Manitoba and has been undergoing an extensive test program since first operation in 1987 July. Based on the knowledge learned from the design, construction, licensing and operational testing of this facility, the design of the 10 MW commercial-size unit is well advanced, and Atomic Energy of Canada Limited is prepared to commit the construction of the first commercial unit. Although the technical demonstration of the concept is important, it is recognized that another crucial element is the public and regulatory acceptance of small nuclear systems in urban areas. The decision by a community to commit the construction of a SLOWPOKE Energy System brings to a sharp focus the current public apprehension about nuclear technologies

EnerGis: A geographical information based system for the evaluation of integrated energy conversion systems in urban areas

International Nuclear Information System (INIS)

Girardin, Luc; Marechal, Francois; Dubuis, Matthias; Calame-Darbellay, Nicole; Favrat, Daniel

2010-01-01

A geographical information system has been developed to model the energy requirements of an urban area. The purpose of the platform is to model with sufficient detail the energy services requirements of a given geographical area in order to allow the evaluation of the integration of advanced integrated energy conversion systems. This tool is used to study the emergence of more efficient cities that realize energy efficiency measures, integrate energy efficient conversion technologies and promote the use of endogenous renewable energy. The model is illustrated with case studies for the energetic planning of the Geneva district (Switzerland).

Energy matching and optimization analysis of waste to energy CCHP (combined cooling, heating and power) system with exergy and energy level

International Nuclear Information System (INIS)

Gao, Penghui; Dai, Yanjun; Tong, YenWah; Dong, Pengwei

2015-01-01

CCHP (combined cooling, heating and power) system as a poly-generation technology has received an increasing attention in field of small scale power systems for applications ranging from residence to utilities. It will also play an important role in waste to energy application for megacities. However, how to evaluate and manage energy utilization of CCHP scientifically remains unclear. In this paper, energy level and exergy analysis are implemented on energy conversion processes to reveal the variation of energy amount and quality in the operation of CCHP system. Moreover, based on the energy level analysis, the methodology of energy matching and optimization for the CCHP system is proposed. By this method, the operational parameters of CCHP system can be deduced to obtain an efficient performance and proper energy utilization. It will be beneficial to understand and operate the CCHP system, and to provide a guiding principle of the energy conversion and management for the CCHP system. - Highlights: • Energy level is implemented to reveal the energy variation of CCHP system. • A mathematical energy level analysis model of CCHP system is proposed. • By energy level analysis between supply and demand, optimal zone is obtained. • This study will be useful for energy matching and optimization of CCHP system

High Tc superconducting energy storage systems

Energy Technology Data Exchange (ETDEWEB)

Werfel, Frank [Adelwitz Technologiezentrum GmbH (ATZ), Arzberg-Adelwitz (Germany)

2012-07-01

Electric energy is basic to heat and light our homes, to power our businesses and to transport people and goods. Powerful storage techniques like SMES, Flywheel, Super Capacitor, and Redox - Flow batteries are needed to increase the overall efficiency, stability and quality of electrical grids. High-Tc superconductors (HTS) possess superior physical and technical properties and can contribute in reducing the dissipation and losses in electric machines as motors and generators, in electric grids and transportation. The renewable energy sources as solar, wind energy and biomass will require energy storage systems even more as a key technology. We survey the physics and the technology status of superconducting flywheel energy storage (FESS) and magnetic energy storage systems (SMES) for their potential of large-scale commercialization. We report about a 10 kWh / 250 kW flywheel with magnetic stabilization of the rotor. The progress of HTS conductor science and technological engineering are basic for larger SMES developments. The performance of superconducting storage systems is reviewed and compared. We conclude that a broad range of intensive research and development in energy storage is urgently needed to produce technological options that can allow both climate stabilization and economic development.

Comparative risk assessment of total energy systems

International Nuclear Information System (INIS)

Soerensen, B.

1982-01-01

The paper discusses a methodology for total impact assessment of energy systems, ideally evaluating all the impacts that a given energy system has on the society in which it is imbedded or into which its introduction is being considered. Impacts from the entire energy conversion chain ('fuel cycle' if the system is fuel-based), including energy storage, transport and transmission, as well as the institutions formed in order to manage the system, should be compared on the basis of the energy service provided. A number of impacts are considered, broadly classified as impacts on satisfaction of biological needs, on health, on environment, on social relations and on the structure of society. Further considerations include impacts related to cost and resilience, and, last but not least, impacts on global relations. The paper discusses a number of published energy studies in the light of the comparative impact assessment methodology outlined above. (author)

Energy management system for stand-alone diesel-wind-biomass microgrid with energy storage system

International Nuclear Information System (INIS)

Wang, Chengshan; Liu, Yixin; Li, Xialin; Guo, Li; Qiao, Lei; Lu, Hai

2016-01-01

An energy management system for stand-alone microgrid composed of diesel generators, wind turbine generator, biomass generator and an ESS (energy storage system) is proposed in this paper. Different operation objectives are achieved by a hierarchical control structure with different time scales. Firstly, the optimal schedules of the diesel generators, wind turbine generator, biomass generator and ESS are determined fifteen minutes ahead according to the super short-term forecast of load and wind speed in the optimal scheduling layer. Comprehensive analysis which takes the uncertainty of load and wind speed into account is conducted in this layer to minimize the operation cost of the system and ensure a desirable range of the state of charge of the ESS. Secondly, the operation points of each unit are regulated dynamically to guarantee real-time power balance and safety range of diesel generation in the real-time control layer, based on which the response capability when suffering significant forecast deviation and other emergency issues, e.g. sudden load-up can be improved. Finally, the effectiveness of the proposed energy management strategy is verified on an RT-Lab based real-time simulation platform, and the economic performances with different types of ESS are analyzed as well. - Highlights: • A hierarchical control strategy is proposed for a stand-alone microgrid. • The uncertainties of load and wind speed have been considered. • Better economic performance and high reliability of the system can be achieved. • The influences of different energy storage systems have been analyzed.

Hydrogen energy systems studies

Energy Technology Data Exchange (ETDEWEB)

Ogden, J.M.; Steinbugler, M.; Dennis, E. [Princeton Univ., NJ (United States)] [and others

1995-09-01

For several years, researchers at Princeton University`s Center for Energy and Environmental Studies have carried out technical and economic assessments of hydrogen energy systems. Initially, we focussed on the long term potential of renewable hydrogen. More recently we have explored how a transition to renewable hydrogen might begin. The goal of our current work is to identify promising strategies leading from near term hydrogen markets and technologies toward eventual large scale use of renewable hydrogen as an energy carrier. Our approach has been to assess the entire hydrogen energy system from production through end-use considering technical performance, economics, infrastructure and environmental issues. This work is part of the systems analysis activity of the DOE Hydrogen Program. In this paper we first summarize the results of three tasks which were completed during the past year under NREL Contract No. XR-11265-2: in Task 1, we carried out assessments of near term options for supplying hydrogen transportation fuel from natural gas; in Task 2, we assessed the feasibility of using the existing natural gas system with hydrogen and hydrogen blends; and in Task 3, we carried out a study of PEM fuel cells for residential cogeneration applications, a market which might have less stringent cost requirements than transportation. We then give preliminary results for two other tasks which are ongoing under DOE Contract No. DE-FG04-94AL85803: In Task 1 we are assessing the technical options for low cost small scale production of hydrogen from natural gas, considering (a) steam reforming, (b) partial oxidation and (c) autothermal reforming, and in Task 2 we are assessing potential markets for hydrogen in Southern California.

Regional Energy Planning Tool for Renewable Integrated Low-Energy District Heating Systems

DEFF Research Database (Denmark)

Tol, Hakan; Dincer, Ibrahim; Svendsen, Svend

2013-01-01

Low-energy district heating systems, operating at low temperature of 55 °C as supply and 25°C as return, can be the energy solution as being the prevailing heating infrastructure in urban areas, considering future energy schemesaiming at increased exploitation of renewable energy sources together...... with low-energy houses in focus with intensified energy efficiency measures. Employing low-temperature operation allows the ease to exploit not only any type of heat source but also low-grade sources, i.e., renewable and industrial waste heat, which would otherwise be lost. In this chapter, a regional...... energy planning tool is described considered with various energy conversion systems based on renewable energy sources to be supplied to an integrated energy infrastructure involving a low-energy district heating, a district cooling, and an electricity grid. The developed tool is performed for two case...

Energy Conversion and Transmission Characteristics Analysis of Ice Storage Air Conditioning System Driven by Distributed Photovoltaic Energy System

Directory of Open Access Journals (Sweden)

Yongfeng Xu

2016-01-01

Full Text Available In order to reduce the investment and operation cost of distributed PV energy system, ice storage technology was introduced to substitute batteries for solar energy storage. Firstly, the ice storage air conditioning system (ISACS driven by distributed photovoltaic energy system (DPES was proposed and the feasibility studies have been investigated in this paper. And then, the theoretical model has been established and experimental work has been done to analyze the energy coupling and transferring characteristics in light-electricity-cold conversion process. In addition, the structure optimization analysis was investigated. Results revealed that energy losses were high in ice making process of ice slide maker with only 17.38% energy utilization efficiency and the energy efficiency and exergy efficiency of ISACS driven by DPES were 5.44% and 67.30%, respectively. So the immersed evaporator and cointegrated exchanger were adopted for higher energy utilization efficiency and better financial rewards in structure optimization. The COP and exergy efficiency of ice maker can be increased to 1.48 and 81.24%, respectively, after optimization and the energy utilization efficiency of ISACS driven by DPES could be improved 2.88 times. Moreover, ISACS has the out-of-the-box function of ordinary air conditioning system. In conclusion, ISACS driven by DPES will have good application prospects in tropical regions without power grid.

Operation optimization of a distributed energy system considering energy costs and exergy efficiency

International Nuclear Information System (INIS)

Di Somma, M.; Yan, B.; Bianco, N.; Graditi, G.; Luh, P.B.; Mongibello, L.; Naso, V.

2015-01-01

Highlights: • Operation optimization model of a Distributed Energy System (DES). • Multi-objective strategy to optimize energy cost and exergy efficiency. • Exergy analysis in building energy supply systems. - Abstract: With the growing demand of energy on a worldwide scale, improving the efficiency of energy resource use has become one of the key challenges. Application of exergy principles in the context of building energy supply systems can achieve rational use of energy resources by taking into account the different quality levels of energy resources as well as those of building demands. This paper is on the operation optimization of a Distributed Energy System (DES). The model involves multiple energy devices that convert a set of primary energy carriers with different energy quality levels to meet given time-varying user demands at different energy quality levels. By promoting the usage of low-temperature energy sources to satisfy low-quality thermal energy demands, the waste of high-quality energy resources can be reduced, thereby improving the overall exergy efficiency. To consider the economic factor as well, a multi-objective linear programming problem is formulated. The Pareto frontier, including the best possible trade-offs between the economic and exergetic objectives, is obtained by minimizing a weighted sum of the total energy cost and total primary exergy input using branch-and-cut. The operation strategies of the DES under different weights for the two objectives are discussed. The operators of DESs can choose the operation strategy from the Pareto frontier based on costs, essential in the short run, and sustainability, crucial in the long run. The contribution of each energy device in reducing energy costs and the total exergy input is also analyzed. In addition, results show that the energy cost can be much reduced and the overall exergy efficiency can be significantly improved by the optimized operation of the DES as compared with the

Wireless Underwater Monitoring Systems Based on Energy Harvestings

Directory of Open Access Journals (Sweden)

Sea-Hee HWANGBO

2013-01-01

Full Text Available One of the important research fields for aquatic exploitation and conservation is underwater wireless sensor network. Since limited energy source for underwater nodes and devices is a main open problem, in this paper, we propose wireless underwater monitoring systems powered by energy harvester which resolves the energy constraint. The target system generates renewable energy from energy harvester and shares the energy with underwater sensor nodes. For the realization of the system, key components to be investigated are discriminated as follows: acoustic modem, actuator, smart battery charge controller, energy harvester and wireless power transfer module. By developing acoustic modem, actuator and smart battery charge controller and utilizing off-the-shelf energy harvester and wireless power transfer module, we design and implement a prototype of the system. Also, we verify the feasibility of concept of target system by conducting indoor and outdoor experiments.

Liability aspects of home energy-rating systems

Energy Technology Data Exchange (ETDEWEB)

Hendrickson, P.L.

1983-10-01

Liability aspects of home energy rating systems are discussed. An introduction to the rating system concept, including types of rating systems, implementation efforts to date, and possible groups to conduct ratings, is also included. The home energy rating system concept involves the periodic rating of the energy efficiency of residential buildings. The rating can provide a relative indication of a home's energy efficiency and also a quantitative estimate of consumption, fuel cost, or both. Primary attention is given to liability issues associated with developing and performing ratings. Secondary attention is given to possible liability associated with misuse of a rating once it has been performed.

Renewable energy systems advanced conversion technologies and applications

CERN Document Server

Luo, Fang Lin

2012-01-01

Energy conversion techniques are key in power electronics and even more so in renewable energy source systems, which require a large number of converters. Renewable Energy Systems: Advanced Conversion Technologies and Applications describes advanced conversion technologies and provides design examples of converters and inverters for renewable energy systems-including wind turbine and solar panel energy systems. Learn Cutting-Edge Techniques for Converters and Inverters Setting the scene, the book begins with a review of the basics of astronomy and Earth physics. It then systematically introduc

Assessing links between energy consumption, freight transport, and economic growth: evidence from dynamic simultaneous equation models.

Science.gov (United States)

Nasreen, Samia; Saidi, Samir; Ozturk, Ilhan

2018-06-01

We investigate this study to examine the relationship between economic growth, freight transport, and energy consumption for 63 developing countries over the period of 1990-2016. In order to make the panel data analysis more homogeneous, we apply the income level of countries to divide the global panel into three sub-panels, namely, lower-middle income countries (LMIC), upper-middle income countries (UMIC), and high-income countries (HIC). Using the generalized method of moments (GMM), the results prove evidence of bidirectional causal relationship between economic growth and freight transport for all selected panels and between economic growth and energy consumption for the high- and upper-middle income panels. For the lower-middle income panel, the causality is unidirectional running from energy consumption to economic growth. Also, the results indicate that the relationship between freight transport and energy use is bidirectional for the high-income countries and unidirectional from freight transport to energy consumption for the upper-middle and lower-middle income countries. Empirical evidence demonstrates the importance of energy for economic activity and rejects the neo-classical assumption that energy is neutral for growth. An important policy recommendation is that there is need of advancements in vehicle technology which can reduce energy intensity from transport sector and improve the energy efficiency in transport activity which in turn allows a greater positive role of transport in global economic activity.

Research for the energy transition. The organization of the energy systems

International Nuclear Information System (INIS)

2017-01-01

The volume on research for the energy transition includes contributions to the FVEE annual meeting 2016 concerning the following issues: status and perspectives of the energy transition, key technologies for the energy transition, political boundary conditions, development trends in photovoltaics, components for the energy supply (wind energy, hydrogen technologies, smart bioenergy concept, contribution of the geosphere), grids and storage systems for the energy transition, research network renewable energies.

Environmental benefits of domestic solar energy systems

International Nuclear Information System (INIS)

Kalogirou, Soteris A.

2004-01-01

All nations of the world depend on fossil fuels for their energy needs. However the obligation to reduce CO 2 and other gaseous emissions in order to be in conformity with the Kyoto agreement is the reason behind which countries turn to non-polluting renewable energy sources. In this paper the pollution caused by the burning of fossil fuels is initially presented followed by a study on the environmental protection offered by the two most widely used renewable energy systems, i.e. solar water heating and solar space heating. The results presented in this paper show that by using solar energy, considerable amounts of greenhouse polluting gasses are avoided. For the case of a domestic water heating system, the saving, compared to a conventional system, is about 80% with electricity or Diesel backup and is about 75% with both electricity and Diesel backup. In the case of space heating and hot water system the saving is about 40%. It should be noted, however, that in the latter, much greater quantities of pollutant gasses are avoided. Additionally, all systems investigated give positive and very promising financial characteristics. With respect to life cycle assessment of the systems, the energy spent for manufacture and installation of the solar systems is recouped in about 1.2 years, whereas the payback time with respect to emissions produced from the embodied energy required for the manufacture and installation of the systems varies from a few months to 9.5 years according to the fuel and the particular pollutant considered. Moreover, due to the higher solar contribution, solar water heating systems have much shorter payback times than solar space heating systems. It can, therefore, be concluded that solar energy systems offer significant protection to the environment and should be employed whenever possible in order to achieve a sustainable future

Integrated energy system for a high performance building

Science.gov (United States)

Jaczko, Kristen

Integrated energy systems have the potential to reduce of the energy consumption of residential buildings in Canada. These systems incorporate components to meet the building heating, cooling and domestic hot water load into a single system in order to reduce energy losses. An integrated energy system, consisting of a variable speed heat pump, cold and hot thermal storage tanks, a photovoltaic/thermal (PV/T) collector array and a battery bank, was designed for the Queen's Solar Design Team's (QSDT) test house. The system uses a radiant floor to provide space- heating and sensible cooling and a dedicated outdoor air system provides ventilation and dehumidifies the incoming fresh air. The test house, the Queen's Solar Education Centre (QSEC), and the integrated energy system were both modelled in TRNSYS. Additionally, a new TRNSYS Type was developed to model the PV/T collectors, enabling the modeling of the collection of energy from the ambient air. A parametric study was carried out in TRNSYS to investigate the effect of various parameters on the overall energy performance of the system. These parameters included the PV/T array size and the slope of the collectors, the heat pump source and load-side inlet temperature setpoints, the compressor speed control and the size of the thermal storage tanks and the battery bank. The controls of the heat pump were found to have a large impact on the performance of the integrated energy system. For example, a low evaporator setpoint improved the overall free energy ratio (FER) of the system but the heat pump performance was lowered. Reducing the heat loss of the PV/T panels was not found to have a large effect on the system performance however, as the heat pump is able to lower the inlet collector fluid temperature, thus reducing thermal losses. From the results of the sensitivity study, a recommended system model was created and this system had a predicted FER of 77.9% in Kingston, Ontario, neglecting the energy consumption of

Risoe energy report 8. The intelligent energy system infrastructure for the future

Energy Technology Data Exchange (ETDEWEB)

Larsen, Hans; Soenderberg Petersen, L. (eds.)

2009-09-15

This report is volume 8 in a series started in 2002, and will take its point of reference in the need for the development of a highly flexible and intelligent energy system infrastructure which facilitates substantial higher amounts of renewable energy than today's energy systems. This intelligent and flexible infrastructure is a prerequisite in achieving the goals set up by IPCC in 2007 on CO{sub 2} reductions as well as ensuring the future security of energy supply in all regions of the world. The report presents a generic approach for future infrastructure issues on local, regional and global scale with focus on the energy system. The report is based on chapters and updates from Risoe Energy Report 1 - 7, as well as input from contributors to the DTU Climate Change Technology workshops and available international literature and reports. (author)

Effect of wind energy system performance on optimal renewable energy model - an analysis

International Nuclear Information System (INIS)

Iniyan, S.; Jagadeesan, T.R.

1998-01-01

The Optimal Renewable Energy Model (OREM) has been developed to determine the optimum level of renewable energy sources utilisation in India for the year 2020-21. The model aims at minimising cost/efficiency ratio and determines the optimum allocation of different renewable energy sources for various end-uses. The extent of social acceptance level, potential limit, demand and reliability will decide the renewable energy distribution pattern and are hence used as constraints in the model. In this paper, the performance and reliability of wind energy system and its effects on OREM model has been analysed. The demonstration windfarm (4 MW) which is situated in Muppandal, a village in the southern part of India, has been selected for the study. The windfarm has 20 wind turbine machines of 200 KW capacity . The average technical availability, real availability and capacity factor have been analysed from 1991 to 1995 and they are found to be 94.1%, 76.4% and 25.5% respectively. The reliability factor of wind energy systems is found to be 0.5 at 10,000 hours. The OREM model is analysed considering the above said factors for wind energy system, solar energy system and biomass energy systems. The model selects wind energy for pumping end-use to an extent of 0.3153 x10 15 KJ. (Author)

Role of renewable energy policies in energy dependency in Finland: System dynamics approach

International Nuclear Information System (INIS)

Aslani, Alireza; Helo, Petri; Naaranoja, Marja

2014-01-01

Highlights: • A system dynamics model for evaluating renewable energy policies on dependency is proposed. • The model considers the role of diversification on dependency and security of energy supply in Finland. • Dependency on imported sources will decrease depends on the defined scenarios in Finland. - Abstract: Objective: We discuss the role of diversification on dependency and security of energy supply. A system dynamics model with especial focus on the role of renewable energy resources (as a portfolio) on Finland’s energy dependency is developed. The purpose is also to cover a part of research gap exists in the system dynamics modeling of energy security investigations. Methods: A causal loops diagram and a system dynamics model evaluate Finnish scenarios of renewable energy policies. The analysis describes the relationship between dynamic factors such as RE encouragement packages, dependency, and energy demand. Results: A causal loops diagram and a system dynamics model evaluate three different Finnish scenarios of renewable energy policies by 2020. Conclusion: Analysis shows that despite 7% electricity/heat consumption growth by 2020 in Finland, dependency on imported sources will decrease between 1% and 7% depend on the defined scenarios. Practice Implications: The proposed model not only helps decision makers to test their scenarios related to renewable energy polices, it can be implemented by other countries

Design and thermodynamic analysis of a hybrid energy storage system based on A-CAES (adiabatic compressed air energy storage) and FESS (flywheel energy storage system) for wind power application

International Nuclear Information System (INIS)

Zhao, Pan; Dai, Yiping; Wang, Jiangfeng

2014-01-01

Electricity generated from renewable wind sources is highly erratic due to the intermittent nature of wind. This uncertainty of wind power can lead to challenges regarding power system operation and dispatch. Energy storage system in conjunction with wind energy system can offset these effects, making the wind power controllable. Moreover, the power spectrum of wind power exhibits that the fluctuations of wind power include various components with different frequencies and amplitudes. Thus, the hybrid energy storage system is more suitable for smoothing out the wind power fluctuations effectively rather than the independent energy storage system. A hybrid energy storage system consisting of adiabatic compressed air energy storage (A-CAES) system and flywheel energy storage system (FESS) is proposed for wind energy application. The design of the proposed system is laid out firstly. The A-CAES system operates in variable cavern pressure, constant turbine inlet pressure mode, whereas the FESS is controlled by constant power strategy. Then, the off-design analysis of the proposed system is carried out. Meanwhile, a parametric analysis is also performed to investigate the effects of several parameters on the system performance, including the ambient conditions, inlet temperature of compressor, storage cavern temperature, maximum and minimum pressures of storage cavern. - Highlights: • A wind-hybrid energy storage system composed of A-CAES and FESS is proposed. • The design of the proposed hybrid energy storage system is laid out. • The off-design analysis of the proposed system is carried out. • A parametric analysis is conducted to examine the system performance

A theoretical analysis of price elasticity of energy demand in multistage energy conversion systems

International Nuclear Information System (INIS)

Lowe, R.

2003-01-01

The objective of this paper is an analytical exploration of the problem of price elasticity of energy demand in multi-stage energy conversion systems. The paper describes in some detail an analytical model of energy demand in such systems. Under a clearly stated set of assumptions, the model makes it possible to explore both the impacts of the number of sub-systems, and of varying sub-system elasticities on overall system elasticity. The analysis suggests that overall price elasticity of energy demand for such systems will tend asymptotically to unity as the number of sub-systems increases. (author)

Miniature photovoltaic energy system for lighting

International Nuclear Information System (INIS)

Awais, M.

1999-01-01

In this project a miniature photovoltaic energy system has been designed and developed, that may be used in remote areas and villages for lighting purposes. System sizing is the important part of the project because it affects the cost of the system. Therefore, first of all system sizing has been done. For conversion of dc voltage of the battery into ac voltage, an inverter has been designed. To charge the battery when the sun is not shining, a standby system has been developed using a bicycle and dynamo. To indicate the battery's state of charge and discharge, a battery monitoring circuit has also been developed. Similarly, to protect the battery from over discharging, a battery protection circuit has been designed. In order to measure how much energy is going from standby system to the battery, an efficient dc electronic energy meter has been designed and developed. The working of the overall system has been tested and found to give good performance. (author)

A Hierarchical Transactive Energy Management System for Energy Sharing in Residential Microgrids

Directory of Open Access Journals (Sweden)

Most Nahida Akter

2017-12-01

Full Text Available This paper presents an analytical framework to develop a hierarchical energy management system (EMS for energy sharing among neighbouring households in residential microgrids. The houses in residential microgrids are categorized into three different types, traditional, proactive and enthusiastic, based on the inclusion of solar photovoltaic (PV systems and battery energy storage systems (BESSs. Each of these three houses has an individual EMS, which is defined as the primary EMS. Two other EMSs (secondary and tertiary are also considered in the proposed hierarchical energy management framework for the purpose of effective energy sharing. The intelligences of each EMS are presented in this paper for the purpose of energy sharing in a residential microgrid along with the priorities. The effectiveness of the proposed hierarchical framework is evaluated on a residential microgrid in Australia. The analytical results clearly reflect that the proposed scheme effectively and efficiently shares the energy among neighbouring houses in a residential microgrid.

Optimal planning of integrated multi-energy systems

DEFF Research Database (Denmark)

van Beuzekom, I.; Gibescu, M.; Pinson, Pierre

2017-01-01

In this paper, a mathematical approach for the optimal planning of integrated energy systems is proposed. In order to address the challenges of future, RES-dominated energy systems, the model deliberates between the expansion of traditional energy infrastructures, the integration...... and sustainability goals for 2030 and 2045. Optimal green- and brownfield designs for a district's future integrated energy system are compared using a one-step, as well as a two-step planning approach. As expected, the greenfield designs are more cost efficient, as their results are not constrained by the existing...

Data-Model Relationship in Text-Independent Speaker Recognition

Directory of Open Access Journals (Sweden)

Stapert Robert

2005-01-01

Full Text Available Text-independent speaker recognition systems such as those based on Gaussian mixture models (GMMs do not include time sequence information (TSI within the model itself. The level of importance of TSI in speaker recognition is an interesting question and one addressed in this paper. Recent works has shown that the utilisation of higher-level information such as idiolect, pronunciation, and prosodics can be useful in reducing speaker recognition error rates. In accordance with these developments, the aim of this paper is to show that as more data becomes available, the basic GMM can be enhanced by utilising TSI, even in a text-independent mode. This paper presents experimental work incorporating TSI into the conventional GMM. The resulting system, known as the segmental mixture model (SMM, embeds dynamic time warping (DTW into a GMM framework. Results are presented on the 2000-speaker SpeechDat Welsh database which show improved speaker recognition performance with the SMM.

Rethinking Participation in Smart Energy System Planning

NARCIS (Netherlands)

Lammers, Imke; Arentsen, Maarten J.

2017-01-01

While the technical layout of smart energy systems is well advanced, the implementation of these systems is slowed down by the current decision-making practice regarding such energy infrastructures. We call for a reorganisation of the decision-making process on local energy planning and address the

Energy Innovation Systems Indicator Report 2012

DEFF Research Database (Denmark)

Klitkou, Antje; Borup, Mads; Iversen, Eric

This report is the first report in a series of reports on energy innovation system indicators produced as part of the activities in the “EIS Strategic research alliance for Energy Innovation Systems and their dynamics – Denmark in global competition”. The work is based on a number of existing......). The report received also valuable input from a project commissioned by IPTS. This project addressed co-operation patterns and knowledge flows in patent documents in the fields of wind energy, photovoltaic energy and concentrating solar power (Iversen and Patel, 2010). The results relevant for this project...

Introduction to Renewable Energy Systems

DEFF Research Database (Denmark)

Ma, Ke; Yang, Yongheng; Blaabjerg, Frede

2014-01-01

. It is concluded that as the quick development of renewable energy, wind power and PV power both show great potential to be largely integrated into the power grid. Power electronics is playing essential role in both of the systems to achieve more controllable, efficient, and reliable energy production......In this chapter, the state-of-the-arts developments of renewable energy are reviewed in respect to the installed power and market share, where wind power and photovoltaic power generation are the main focuses due to the fast growing speed and large share of installed capacity. Some basic principles...... of operation, mission profiles, as well as power electronics solutions and corresponding controls are discussed respectively in the case of wind power and photovoltaic power systems. Finally a few development trends for renewable energy conversions are also given from a power electronics point of view...

Modeling of long-term energy system of Japan

International Nuclear Information System (INIS)

Gotoh, Yoshitaka; Sato, Osamu; Tadokoro, Yoshihiro

1999-07-01

In order to analyze the future potential of reducing carbon dioxide emissions, the long-term energy system of Japan was modeled following the framework of the MARKAL model, and the database of energy technology characteristics was developed. First, a reference energy system was built by incorporating all important energy sources and technologies that will be available until the year 2050. This system consists of 25 primary energy sources, 33 technologies for electric power generation and/or low temperature heat production, 97 technologies for energy transformation, storage, and distribution, and 170 end-use technologies. Second, the database was developed for the characteristics of individual technologies in the system. The characteristic data consists of input and output of energy carriers, efficiency, availability, lifetime, investment cost, operation and maintenance cost, CO 2 emission coefficient, and others. Since a large number of technologies are included in the system, this report focuses modeling of a supply side, and involves the database of energy technologies other than for end-use purposes. (author)

Renewable energy systems in Mexico: Installation of a hybrid system

Science.gov (United States)

Pate, Ronald C.

1993-05-01

Sandia has been providing technical leadership on behalf of DOE and CORECT on a working level cooperative program with Mexico on renewable energy (PROCER). As part of this effort, the Sandia Design Assistance Center (DAC) and the solar energy program staff at Instituto de Investigaciones Electricas (IIE) in Cuernavaca, Mexico, recently reached agreement on a framework for mutually beneficial technical collaboration on the monitoring and field evaluation of renewable energy systems in Mexico, particularly village-scale hybrid systems. This trip was made for the purpose of planning the details for the joint installation of a data acquisition system (DAS) on a recently completed PV/Wind/Diesel hybrid system in the village of Xcalac on the Southeast coast of the state of Quintana Roo, Mexico. The DAS installation will be made during the week of March 15, 1993. While in Mexico, discussions were also held with personnel from.the National Autonomous University of Mexico (UNAM) Solar Energy Laboratory and several private sector companies with regard to renewable energy project activities and technical and educational support needs in Mexico.

Energy systems Diagnosis in developing countries

International Nuclear Information System (INIS)

Girod, J.

1991-01-01

Energy systems diagnosis is necessary to allow evaluation of energy balance by administration and political authorities of a country. First, the author describes the principle stages of energetic diagnosis. Then this work is divided into three parts: First part: Energy consumption diagnosis in several districts (families, utilities, agriculture, transport, industry) Second part: Energy supplies diagnosis (energy markets). Third part: Interactions between energy consumption and energy supply. 28 figs.; 52 tabs.; 107 refs

Biomass energy inventory and mapping system

Energy Technology Data Exchange (ETDEWEB)

Kasile, J.D. [Ohio State Univ., Columbus, OH (United States)

1993-12-31

A four-stage biomass energy inventory and mapping system was conducted for the entire State of Ohio. The product is a set of maps and an inventory of the State of Ohio. The set of amps and an inventory of the State`s energy biomass resource are to a one kilometer grid square basis on the Universal Transverse Mercator (UTM) system. Each square kilometer is identified and mapped showing total British Thermal Unit (BTU) energy availability. Land cover percentages and BTU values are provided for each of nine biomass strata types for each one kilometer grid square. LANDSAT satellite data was used as the primary stratifier. The second stage sampling was the photointerpretation of randomly selected one kilometer grid squares that exactly corresponded to the LANDSAT one kilometer grid square classification orientation. Field sampling comprised the third stage of the energy biomass inventory system and was combined with the fourth stage sample of laboratory biomass energy analysis using a Bomb calorimeter and was then used to assign BTU values to the photointerpretation and to adjust the LANDSAT classification. The sampling error for the whole system was 3.91%.

Direct and indirect economics of wind energy systems relative to fuel based systems

Energy Technology Data Exchange (ETDEWEB)

Sorensen, B

1977-01-01

It is shown that the addition of an energy-storage system of modest capacity, to a wind energy generator, provides a total-wind-energy electricity-generating system as dependable as current alternative means of producing electricity. It is further shown, based on projections of the mass-production costs of wind-energy generators and energy-storage systems, that such combined systems, as well as fuel-saving generators without storage, appear economically competitive to the alternatives, provided the comparison is made over the entire life cycle of the systems.

Probabilistic Approaches to Energy Systems

DEFF Research Database (Denmark)

Iversen, Jan Emil Banning

of renewable energy generation. Particularly we focus on producing forecasting models that can predict renewable energy generation, single user demand, and provide advanced forecast products that are needed for an efficient integration of renewable energy into the power generation mix. Such forecasts can...... integration of renewable energy.Thus forecast products should be developed in unison with the decision making tool as they are two sides of the same overall challenge.......Energy generation from wind and sun is increasing rapidly in many parts of the world. This presents new challenges on how to integrate this uncertain, intermittent and non-dispatchable energy source. This thesis deals with forecasting and decision making in energy systems with a large proportion...

Translating EU renewable energy policy for insular energy systems: Reunion Island's quest for energy autonomy

Directory of Open Access Journals (Sweden)

Matthew Sawatzky

2017-12-01

Full Text Available Recognition of the negative impacts of climate change has led to agreement on the need to decarbonise energy systems through the employment of renewable energy. With many national and transnational policies in place, the options available to insular energy systems (IES differ from those of interconnected areas due to fragility in their production and distribution networks. Based on the concepts of policy mobility and translation, this study examines the interplay of EU renewable energy policy and insular governance processes aimed at achieving energy autonomy through renewable energy development. Reunion Island, a French Overseas Department and Region, is used as a case study to examine local energy governance processes, aspects that shape regional translation of national and EU policy, and the potential effects that create structures and pathways of energy transition. The study shows that Reunion Island’s regional Energy Governance Committee has significant application potential as a governance tool in other IES and small islands within the EU, but that renewable energy development is restricted due to national policy measures and path dependent governance structural constraints.

Emerging nuclear energy systems: Economic challenge: Revision 1

International Nuclear Information System (INIS)

Nuckolls, J.H.

1986-01-01

Future nuclear energy systems may achieve substantially lower energy costs than those of existing fossil energy systems and comparable capital costs. Such low cost nuclear energy would provide a strong economic incentive to minimize the use of fossil fuels. If these low cost nuclear energy systems emerge in the next few decades, 21st century civilization may be able to avert potentially disastrous CO 2 induced global climate changes. 12 refs., 1 fig

Integrated energy systems and local energy markets

International Nuclear Information System (INIS)

Lund, Henrik; Muenster, Ebbe

2006-01-01