WorldWideScience

Sample records for model potential energy

  1. Evaluation of bio-energy potential using world energy models; Sekai energy model ni yoru bio energy no potential hyoka

    Energy Technology Data Exchange (ETDEWEB)

    Fujino, J.; Yamaji, K. [The University of Tokyo, Tokyo (Japan); Yamamoto, H. [Central Research Institute of Electric Power Industry, Tokyo (Japan)

    1997-01-30

    Bio-energy potential is evaluated using world energy models. The world energy model is a dynamic model by which the total cost of energy systems between 1995 and 2055 can be minimized on the basis of the optimization type world energy demand and supply model. For the given utilization costs of transportation, recovery and planting, the utilization of bio-energy is promoted even under the cost minimization condition. However, the utilization amount varies in a wide range by changing the utilization costs. Among conversion technologies of bio-energy, it is biomass liquefaction that provides the largest utilization amount. Thermal demand, direct combustion for power generation, and biomass gasification follow to the above. Biomass-integrated gasifier/gas turbine (BIG/GT) is to be used up to 2020. It is not to be used after 2030, due to the complete shift to the biomass liquefaction. For a model including the utilization of fast breeder after 2030, the utilization amount of bio-energy is not to change. Competition with food and land utilization is to be investigated. 11 refs., 19 figs., 4 tabs.

  2. Evaluation of bio-energy potential using world energy models; Sekai energy model ni yoru bio energy no potential hyoka

    Energy Technology Data Exchange (ETDEWEB)

    Fujino, J.; Yamaji, K. [The University of Tokyo, Tokyo (Japan); Yamamoto, H. [Central Research Institute of Electric Power Industry, Tokyo (Japan)

    1997-01-30

    Bio-energy potential is evaluated using world energy models. The world energy model is a dynamic model by which the total cost of energy systems between 1995 and 2055 can be minimized on the basis of the optimization type world energy demand and supply model. For the given utilization costs of transportation, recovery and planting, the utilization of bio-energy is promoted even under the cost minimization condition. However, the utilization amount varies in a wide range by changing the utilization costs. Among conversion technologies of bio-energy, it is biomass liquefaction that provides the largest utilization amount. Thermal demand, direct combustion for power generation, and biomass gasification follow to the above. Biomass-integrated gasifier/gas turbine (BIG/GT) is to be used up to 2020. It is not to be used after 2030, due to the complete shift to the biomass liquefaction. For a model including the utilization of fast breeder after 2030, the utilization amount of bio-energy is not to change. Competition with food and land utilization is to be investigated. 11 refs., 19 figs., 4 tabs.

  3. Novel mixture model for the representation of potential energy surfaces

    Science.gov (United States)

    Pham, Tien Lam; Kino, Hiori; Terakura, Kiyoyuki; Miyake, Takashi; Dam, Hieu Chi

    2016-10-01

    We demonstrate that knowledge of chemical physics on a materials system can be automatically extracted from first-principles calculations using a data mining technique; this information can then be utilized to construct a simple empirical atomic potential model. By using unsupervised learning of the generative Gaussian mixture model, physically meaningful patterns of atomic local chemical environments can be detected automatically. Based on the obtained information regarding these atomic patterns, we propose a chemical-structure-dependent linear mixture model for estimating the atomic potential energy. Our experiments show that the proposed mixture model significantly improves the accuracy of the prediction of the potential energy surface for complex systems that possess a large diversity in their local structures.

  4. Spatial Modelling of Solar energy Potential in Kenya

    Directory of Open Access Journals (Sweden)

    Francis Omondi Oloo

    2015-06-01

    Full Text Available Solar energy is one of the readily available renewable energy resources in the developing countries within the tropical region. Kenya is one of the countries which receive an average of approximately 6.5 sunshine hours in a single day throughout the year. However, there is slow adoption of solar energy resources in the country due to limited information on the spatial variability solar energy potential. This study aims at assessing the potential of photovoltaic solar energy in Kenya. The factors that influence incident solar radiation which were considered in this task included atmospheric transmissivity and topography. The influence of atmospheric transmissivity was factored in by modelling monthly transmissivity factors from a combination of cloud cover, diffuse ratios and the effect of altitude. The contribution of topography was included by applying hemispherical viewshed analysis to determine the amount of incident global radiation on the surface based on the orientation of the terrain. GIS concepts were used to integrate the spatial datasets from different themes. The results showed that, about 70% of the land area in Kenya has the potential of receiving approximately 5kWh/m2/day throughout the year. In outline, this work successfully assessed the spatio-temporal variability in the characteristics of solar energy potential in Kenya and can be used as a basis for policy support in the country.

  5. Molecular spinless energies of the modified Rosen-Morse potential energy model in higher spatial dimensions

    Science.gov (United States)

    Jia, Chun-Sheng; Dai, Jian-Wei; Zhang, Lie-Hui; Liu, Jian-Yi; Zhang, Guang-Dong

    2015-01-01

    We solve the Klein-Gordon equation with the modified Rosen-Morse potential energy model in D spatial dimensions. The bound state energy equation has been obtained by using the supersymmetric WKB approximation approach. We find that the inter-dimensional degeneracy symmetry exists for the molecular system represented by the modified Rosen-Morse potential. For fixed vibrational and rotational quantum numbers, the relativistic energies for the 61Πu state of the 7Li2 molecule and the X3Π state of the SiC radical increase as D increases. We observe that the behavior of the relativistic vibrational energies in higher dimensions remains similar to that of the three-dimensional system.

  6. The extended Lennard-Jones potential energy function: A simpler model for direct-potential-fit analysis

    Science.gov (United States)

    Hajigeorgiou, Photos G.

    2016-12-01

    An analytical model for the diatomic potential energy function that was recently tested as a universal function (Hajigeorgiou, 2010) has been further modified and tested as a suitable model for direct-potential-fit analysis. Applications are presented for the ground electronic states of three diatomic molecules: oxygen, carbon monoxide, and hydrogen fluoride. The adjustable parameters of the extended Lennard-Jones potential model are determined through nonlinear regression by fits to calculated rovibrational energy term values or experimental spectroscopic line positions. The model is shown to lead to reliable, compact and simple representations for the potential energy functions of these systems and could therefore be classified as a suitable and attractive model for direct-potential-fit analysis.

  7. Estimating potential saving with energy consumption behaviour model in higher education institutions

    Directory of Open Access Journals (Sweden)

    Mohd Hafizal Ishak

    2016-11-01

    Full Text Available Towards sustainable Higher Education Institutions (HEIs, energy consumption behaviour is one of several issues that require an attention by facilities manager. Information from the behavioural aspect would be useful for facilities manager on managing the energy and determining potential energy saving. A lack of information negatively affects this aim. Hence, this paper proposes a methodology for assessing the energy consumption behaviour with the objective determining potential energy saving. The method used energy culture framework as basis and joined with centrographic approach and multiple-regression analysis. A self-administrated survey carried out involving 1400 respondents in selected HEIs. There are four types of energy use among students in HEIs namely, 'high', 'low', ‘medium’ and 'conserve' determined from the centrographic analysis. The energy consumption behaviour model was developed and tested against the holdout sample. Through the model's application, there is a vast potential for energy savings with over 55 kWh daily among the students.

  8. Modelling thermal stratification in the North Sea: Application of a 2-D potential energy model

    DEFF Research Database (Denmark)

    Nielsen, Morten Holtegaard; St. John, Michael

    2001-01-01

    energy as water masses of different densities are mixed in the field of gravity. A constant ratio between the gain in potential energy and the production of TKE is assumed, known as the flux Richardson number. The model is comprised of 0·5m vertical layers with a temporal time step of 1 day. The model...... is forced with wind, dew point temperature from Ekofisk oilfield in the central North Sea, and tidal current and atmospheric radiation. The model is used to simulate the seasonal cycle of stratification in the central North Sea in the years 1988, 1989 and 1990 and is compared to density profiles...... an R2=0·97 between observed and predicted upper layer temperatures. However, the model is less successful in the prediction of temperatures of the intermediate and deep layers (R2=0·46 and 0·14) due to small deviations in thermocline depth and variations in tidal amplitude. The model was then applied...

  9. Modeling In-stream Tidal Energy Extraction and Its Potential Environmental Impacts

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Zhaoqing; Wang, Taiping; Copping, Andrea; Geerlofs, Simon H.

    2014-09-30

    In recent years, there has been growing interest in harnessing in-stream tidal energy in response to concerns of increasing energy demand and to mitigate climate change impacts. While many studies have been conducted to assess and map tidal energy resources, efforts for quantifying the associated potential environmental impacts have been limited. This paper presents the development of a tidal turbine module within a three-dimensional unstructured-grid coastal ocean model and its application for assessing the potential environmental impacts associated with tidal energy extraction. The model is used to investigate in-stream tidal energy extraction and associated impacts on estuarine hydrodynamic and biological processes in a tidally dominant estuary. A series of numerical experiments with varying numbers and configurations of turbines installed in an idealized estuary were carried out to assess the changes in the hydrodynamics and biological processes due to tidal energy extraction. Model results indicated that a large number of turbines are required to extract the maximum tidal energy and cause significant reduction of the volume flux. Preliminary model results also indicate that extraction of tidal energy increases vertical mixing and decreases flushing rate in a stratified estuary. The tidal turbine model was applied to simulate tidal energy extraction in Puget Sound, a large fjord-like estuary in the Pacific Northwest coast.

  10. Deformed Potential Energy of 263Db in a Generalized Liquid Drop Model

    Institute of Scientific and Technical Information of China (English)

    陈宝秋; 马中玉; 赵耀林

    2003-01-01

    The macroscopic deformed potential energy for super-heavy nuclei 263 Db,which governs the entrance and alpha decay channels,is determined within a generalized liquid drop model(GLDM).A quasi-molecular shape is as sumed in the GLDM,which includes volume-,surface-,and Coulomb-energies,proximity effects,mass asymmetry,and an accurate nuclear radius.The microscopic single particle energies are derived from a shell model in an axially deformed Woods-Saxon potential with a quasi-molecular shape.The shell correction is calculated by the Strutinsky method.The total deformed potential energy of a nucleus can be calculated by the macro-microscopic method as the summation of the liquid-drop energy and the Strutinsky shell correction.The theory is applied to predict the deformed potential energy of the experiment 22Ne + 241Am → 263Db* → 259Db + 4n,which was performed on the Heavy Ion Accelerator in Lanzhou.It is found that the neck in the quasi-molecular shape is responsible for the deep valley of the fusion barrier due to the shell corrections.In the cold fusion path,the double-hump fusion barrier is predicted by the shell correction and complete fusion events may occur.

  11. Potential energy savings

    DEFF Research Database (Denmark)

    Schultz, Jørgen Munthe

    1996-01-01

    This chapter describes the chosen methods for estimating the potential energy savings if ordinary window glazing is exchanged with aerogel glazing as well as commercial low-energy glazings.......This chapter describes the chosen methods for estimating the potential energy savings if ordinary window glazing is exchanged with aerogel glazing as well as commercial low-energy glazings....

  12. Calculation of energy spectrum of $^{12}$C isotope with modified Yukawa potential by cluster models

    Indian Academy of Sciences (India)

    MOHAMMAD REZA SHOJAE; NAFISEH ROSHAN BAKHT

    2016-10-01

    In this paper, we have calculated the energy spectrum of 12C isotope in two-cluster models, $3\\alpha$ cluster model and $^8$Be + $\\alpha$ cluster model. We use the modified Yukawa potential for interaction between theclusters and solve the Schrödinger equation using Nikiforov–Uvarov method to calculate the energy spectrum. Then, we increase the accuracy by adding spin-orbit coupling and tensor force and solve them by perturbationtheory in both models. Finally, the calculated results for both models are compared with each other and with the experimental data. The results show that the isotope $^{12}$C should be considered as a three-$\\alpha$ cluster and themodified Yukawa potential is adaptable for cluster interactions.

  13. Modeling Irrigation Networks for the Quantification of Potential Energy Recovering: A Case Study

    Directory of Open Access Journals (Sweden)

    Modesto Pérez-Sánchez

    2016-06-01

    Full Text Available Water irrigation systems are required to provide adequate pressure levels in any sort of network. Quite frequently, this requirement is achieved by using pressure reducing valves (PRVs. Nevertheless, the possibility of using hydraulic machines to recover energy instead of PRVs could reduce the energy footprint of the whole system. In this research, a new methodology is proposed to help water managers quantify the potential energy recovering of an irrigation water network with adequate conditions of topographies distribution. EPANET has been used to create a model based on probabilities of irrigation and flow distribution in real networks. Knowledge of the flows and pressures in the network is necessary to perform an analysis of economic viability. Using the proposed methodology, a case study has been analyzed in a typical Mediterranean region and the potential available energy has been estimated. The study quantifies the theoretical energy recoverable if hydraulic machines were installed in the network. Particularly, the maximum energy potentially recovered in the system has been estimated up to 188.23 MWh/year with a potential saving of non-renewable energy resources (coal and gas of CO2 137.4 t/year.

  14. Crossover to potential energy landscape dominated dynamics in a model glass-forming liquid

    DEFF Research Database (Denmark)

    Schrøder, Thomas; Sastry, S.; Dyre, Jeppe;

    2000-01-01

    An equilibrated model glass-forming liquid is studied by mapping successive configurations produced by molecular dynamics simulation onto a time series of inherent structures (local minima in the potential energy). Using this "inherent dynamics" approach we find direct numerical evidence for the ...

  15. Archimedes' Law and Potential Energy: Modelling and Simulation with a Spreadsheet.

    Science.gov (United States)

    Silva, A. Alberto

    1998-01-01

    Addresses some basic aspects of Archimedes' law. Focus is on potential energy relationships so as to elucidate some common misunderstandings and to facilitate making bridges with other physical topics. A spreadsheet model is used as a simulation tool. (Author/NB)

  16. Deformed Potential Energy of Super Heavy Element Z = 120 in a Generalized Liquid Drop Model

    Institute of Scientific and Technical Information of China (English)

    CHEN Bao-Qiu; MA Zhong-Yu; ZHU Zhi-Yuan; SONG Hong-Qiu; ZHAO Yao-Lin

    2005-01-01

    @@ The macroscopic deformed potential energy for super-heavy elements Z = 120 is determined within a generalized liquid drop model (GLDM). The shell correction is calculated with the Strutinsky method and the microscopic single particle energies are derived from the shell model in an axially deformed Woods-Saxon potential with the same quasi-molecular shape. The total potential energy of a nucleus is calculated by the macro-microscopic method as the summation of the liquid-drop energy and the Strutinsky shell correction. The theory is adopted to describe the deformed potential energies in a set of cold reactions. The neck in the quasi-molecular shape is responsible to the deep valley of the fusion barrier due to shell corrections. In the cold fusion path, the doublehump fusion barrier is predicted by the shell correction and complete fusion events may occur. The results show that some of projectile-target combinations in the entrance channel, such as 50Ca+252Fm→ 302120* and 58Fe+244pu→ 302120*, favour the fusion reaction, which can be considered as candidates for the synthesis of super heavy nuclei Z = 120 and the former might be the best cold fusion reaction to produce the nucleus 302120among them.

  17. Modelling the potential for wind energy integration on China’s coal-heavy electricity grid

    Science.gov (United States)

    Davidson, Michael R.; Zhang, Da; Xiong, Weiming; Zhang, Xiliang; Karplus, Valerie J.

    2016-07-01

    Expanding the use of wind energy for electricity generation forms an integral part of China’s efforts to address degraded air quality and climate change. However, the integration of wind energy into China’s coal-heavy electricity system presents significant challenges owing to wind’s variability and the grid’s system-wide inflexibilities. Here we develop a model to predict how much wind energy can be generated and integrated into China’s electricity mix, and estimate a potential production of 2.6 petawatt-hours (PWh) per year in 2030. Although this represents 26% of total projected electricity demand, it is only 10% of the total estimated physical potential of wind resources in the country. Increasing the operational flexibility of China’s coal fleet would allow wind to deliver nearly three-quarters of China’s target of producing 20% of primary energy from non-fossil sources by 2030.

  18. Cowichan Valley energy mapping and modelling. Report 3 - Analysis of potentially applicable distributed energy opportunities. Final report. [Vancouver Island, Canada

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-06-15

    The driving force behind the Integrated Energy Mapping and Analysis project was the identification and analysis of a suite of pathways that the Cowichan Valley Regional District (CVRD) can utilise to increase its energy resilience, as well as reduce energy consumption and GHG emissions, with a primary focus on the residential sector. Mapping and analysis undertaken will support provincial energy and GHG reduction targets, and the suite of pathways outlined will address a CVRD internal target that calls for 75% of the region's energy within the residential sector to come from locally sourced renewables by 2050. The target has been developed as a mechanism to meet resilience and climate action target. The maps and findings produced are to be integrated as part of a regional policy framework currently under development. The third task built upon the findings of the previous two and undertook an analysis of potentially applicable distributed energy opportunities. These opportunities were analysed given a number of different parameters, which were decided upon in consultation with the CVRD. The primary output of this task was a series of cost figures for the various technologies, thus allowing comparison on a cents/kWh basis. All of the cost figures from this task have been entered into a tailor made Excel model. This 'technology cost' model is linked to the Excel scenario model utilised in task 4. As a result, as technology costs change, they can be updated accordingly and be reflected in the scenarios. Please note, that the technologies considered at present in the technology cost model are well-proven technologies, available in the market today, even though the output is being used for an analysis of development until 2050. Task 3 results are detailed in this report and both presents an initial screening for various local renewable energies, and provides the CVRD with the means of evaluating the costs and benefits of local energy productions versus

  19. New statistical potential for quality assessment of protein models and a survey of energy functions

    Directory of Open Access Journals (Sweden)

    Rykunov Dmitry

    2010-03-01

    Full Text Available Abstract Background Scoring functions, such as molecular mechanic forcefields and statistical potentials are fundamentally important tools in protein structure modeling and quality assessment. Results The performances of a number of publicly available scoring functions are compared with a statistical rigor, with an emphasis on knowledge-based potentials. We explored the effect on accuracy of alternative choices for representing interaction center types and other features of scoring functions, such as using information on solvent accessibility, on torsion angles, accounting for secondary structure preferences and side chain orientation. Partially based on the observations made, we present a novel residue based statistical potential, which employs a shuffled reference state definition and takes into account the mutual orientation of residue side chains. Atom- and residue-level statistical potentials and Linux executables to calculate the energy of a given protein proposed in this work can be downloaded from http://www.fiserlab.org/potentials. Conclusions Among the most influential terms we observed a critical role of a proper reference state definition and the benefits of including information about the microenvironment of interaction centers. Molecular mechanical potentials were also tested and found to be over-sensitive to small local imperfections in a structure, requiring unfeasible long energy relaxation before energy scores started to correlate with model quality.

  20. Potential of Solar Energy in Kota Kinabalu, Sabah: An Estimate Using a Photovoltaic System Model

    Science.gov (United States)

    Markos, F. M.; Sentian, J.

    2016-04-01

    Solar energy is becoming popular as an alternative renewable energy to conventional energy source, particularly in the tropics, where duration and intensity of solar radiation are longer. This study is to assess the potential of solar energy generated from solar for Kota Kinabalu, a rapidly developing city in the State of Sabah, Malaysia. A year data of solar radiation was obtained using pyranometer, which was located at Universiti Malaysia Sabah (6.0367° N, 116.1186° E). It was concluded that the annual average solar radiation received in Kota Kinabalu was 182 W/m2. In estimating the potential energy generated from solar for Kota Kinabalu city area, a photovoltaic (PV) system model was used. The results showed that, Kota Kinabalu is estimated to produce 29,794 kWh/m2 of electricity from the solar radiation received in a year. This is equivalent to 0.014 MW of electricity produced just by using one solar panel. Considering the power demand in Sabah by 2020 is 1,331 MW, this model showed that the solar energy can contribute around 4% of energy for power demand, with 1 MW capacity of the PV system. 1 MW of PV system installation will require about 0.0328% from total area of the city. This assessment could suggest that, exploration for solar power energy as an alternative source of renewable energy in the city can be optimised and designed to attain significant higher percentage of contribution to the energy demand in the state.

  1. Upcrowding energy co-operatives - Evaluating the potential of crowdfunding for business model innovation of energy co-operatives.

    Science.gov (United States)

    Dilger, Mathias Georg; Jovanović, Tanja; Voigt, Kai-Ingo

    2017-08-01

    Practice and theory have proven the relevance of energy co-operatives for civic participation in the energy turnaround. However, due to a still low awareness and changing regulation, there seems an unexploited potential of utilizing the legal form 'co-operative' in this context. The aim of this study is therefore to investigate the crowdfunding implementation in the business model of energy co-operatives in order to cope with the mentioned challenges. Based on a theoretical framework, we derive a Business Model Innovation (BMI) through crowdfunding including synergies and differences. A qualitative study design, particularly a multiple-case study of energy co-operatives, was chosen to prove the BMI and to reveal barriers. The results show that although most co-operatives are not familiar with crowdfunding, there is strong potential in opening up predominantly local structures to a broader group of members. Building on this, equity-based crowdfunding is revealed to be suitable for energy co-operatives as BMI and to accompany other challenges in the same way. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Random forest-based protein model quality assessment (RFMQA) using structural features and potential energy terms.

    Science.gov (United States)

    Manavalan, Balachandran; Lee, Juyong; Lee, Jooyoung

    2014-01-01

    Recently, predicting proteins three-dimensional (3D) structure from its sequence information has made a significant progress due to the advances in computational techniques and the growth of experimental structures. However, selecting good models from a structural model pool is an important and challenging task in protein structure prediction. In this study, we present the first application of random forest based model quality assessment (RFMQA) to rank protein models using its structural features and knowledge-based potential energy terms. The method predicts a relative score of a model by using its secondary structure, solvent accessibility and knowledge-based potential energy terms. We trained and tested the RFMQA method on CASP8 and CASP9 targets using 5-fold cross-validation. The correlation coefficient between the TM-score of the model selected by RFMQA (TMRF) and the best server model (TMbest) is 0.945. We benchmarked our method on recent CASP10 targets by using CASP8 and 9 server models as a training set. The correlation coefficient and average difference between TMRF and TMbest over 95 CASP10 targets are 0.984 and 0.0385, respectively. The test results show that our method works better in selecting top models when compared with other top performing methods. RFMQA is available for download from http://lee.kias.re.kr/RFMQA/RFMQA_eval.tar.gz.

  3. Interparticle potential energy for D-dimensional electromagnetic models from the corresponding scalar ones

    CERN Document Server

    Accioly, Antonio; Correia, Gilson; Brito, Gustavo; de Almeida, José; Herdy, Wallace

    2016-01-01

    Using a method based on the generating functional plus a kind of "correspondence principle" --- which acts as a bridge between the electromagnetic and scalar fields --- it is shown that the interparticle potential energy concerning a given $D$-dimensional electromagnetic model can be obtained in a simple way from that related to the corresponding scalar system. The $D$-dimensional electromagnetic potential for a general model containing higher derivatives is then found from the corresponding scalar one and the behavior of the former is analyzed at large as well as small distances. In addition, we investigate the presence of ghosts in the four-dimensional version of the potential associated with the model above and analyze the reason why the Coulomb singularity is absent from this system. The no-go theorem by Ostrogradski is demystified as well.

  4. Renewable energy: GIS-based mapping and modelling of potentials and demand

    Science.gov (United States)

    Blaschke, Thomas; Biberacher, Markus; Schardinger, Ingrid.; Gadocha, Sabine; Zocher, Daniela

    2010-05-01

    Worldwide demand of energy is growing and will continue to do so for the next decades to come. IEA has estimated that global primary energy demand will increase by 40 - 50% from 2003 to 2030 (IEA, 2005) depending on the fact whether currently contemplated energy policies directed towards energy-saving and fuel-diversification will be effectuated. The demand for Renewable Energy (RE) is undenied but clear figures and spatially disaggregated potentials for the various energy carriers are very rare. Renewable Energies are expected to reduce pressures on the environment and CO2 production. In several studies in Germany (North-Rhine Westphalia and Lower Saxony) and Austria we studied the current and future pattern of energy production and consumption. In this paper we summarize and benchmark different RE carriers, namely wind, biomass (forest and non-forest, geothermal, solar and hydro power. We demonstrate that GIS-based scalable and flexible information delivery sheds new light on the prevailing metaphor of GIS as a processing engine serving needs of users more on demand rather than through ‘maps on stock'. We compare our finding with those of several energy related EU-FP7 projects in Europe where we have been involved - namely GEOBENE, REACCESS, ENERGEO - and demonstrate that more and more spatial data will become available together with tools that allow experts to do their own analyses and to communicate their results in ways which policy makers and the public can readily understand and use as a basis for their own actions. Geoportals in combination with standardised geoprocessing today supports the older vision of an automated presentation of data on maps, and - if user privileges are given - facilities to interactively manipulate these maps. We conclude that the most critical factor in modelling energy supply and demand remain the economic valuation of goods and services, especially the forecast of future end consumer energy costs.

  5. Empirical models for predicting wind potential for wind energy applications in rural locations of Nigeria

    Directory of Open Access Journals (Sweden)

    F. C. Odo, G. U. Akubue, S. U. Offiah, P. E. Ugwuoke

    2013-01-01

    Full Text Available In this paper, we use the correlation between the average wind speed and ambient temperature to develop models for predicting wind potentials for two Nigerian locations. Assuming that the troposphere is a typical heterogeneous mixture of ideal gases, we find that for the studied locations, wind speed clearly correlates with ambient temperature in a simple polynomial of 3rd degree. The coefficient of determination and root-mean-square error of the models are 0.81; 0.0024 and 0.56; 0.0041, respectively, for Enugu (6.40N; 7.50E and Owerri (5.50N; 7.00E. These results suggest that the temperature-based model can be used, with acceptable accuracy, in predicting wind potentials needed for preliminary design assessment of wind energy conversion devices for the locations and others with similar meteorological conditions.

  6. Empirical models for predicting wind potential for wind energy applications in rural locations of Nigeria

    Energy Technology Data Exchange (ETDEWEB)

    Odo, F.C. [National Centre for Energy Research and Development, University of Nigeria, Nsukka (Nigeria); Department of Physics and Astronomy, University of Nigeria, Nsukka (Nigeria); Akubue, G.U.; Offiah, S.U.; Ugwuoke, P.E. [National Centre for Energy Research and Development, University of Nigeria, Nsukka (Nigeria)

    2013-07-01

    In this paper, we use the correlation between the average wind speed and ambient temperature to develop models for predicting wind potentials for two Nigerian locations. Assuming that the troposphere is a typical heterogeneous mixture of ideal gases, we find that for the studied locations, wind speed clearly correlates with ambient temperature in a simple polynomial of 3rd degree. The coefficient of determination and root-mean-square error of the models are 0.81; 0.0024 and 0.56; 0.0041, respectively, for Enugu (6.40N; 7.50E) and Owerri (5.50N; 7.00E). These results suggest that the temperature-based model can be used, with acceptable accuracy, in predicting wind potentials needed for preliminary design assessment of wind energy conversion devices for the locations and others with similar meteorological conditions.

  7. Bottom-up modelling of energy demand and technical energy savings potential in the Irish residential sector

    OpenAIRE

    Dineen, Denis

    2014-01-01

    The International Energy Agency has repeatedly identified increased end-use energy efficiency as the quickest, least costly method of green house gas mitigation, most recently in the 2012 World Energy Outlook, and urges all governing bodies to increase efforts to promote energy efficiency policies and technologies. The residential sector is recognised as a major potential source of cost effective energy efficiency gains. Within the EU this relative importance can be seen from a review of the ...

  8. A study of potential energy curves from the model space quantum Monte Carlo method

    Energy Technology Data Exchange (ETDEWEB)

    Ohtsuka, Yuhki; Ten-no, Seiichiro, E-mail: tenno@cs.kobe-u.ac.jp [Department of Computational Sciences, Graduate School of System Informatics, Kobe University, Nada-ku, Kobe 657-8501 (Japan)

    2015-12-07

    We report on the first application of the model space quantum Monte Carlo (MSQMC) to potential energy curves (PECs) for the excited states of C{sub 2}, N{sub 2}, and O{sub 2} to validate the applicability of the method. A parallel MSQMC code is implemented with the initiator approximation to enable efficient sampling. The PECs of MSQMC for various excited and ionized states are compared with those from the Rydberg-Klein-Rees and full configuration interaction methods. The results indicate the usefulness of MSQMC for precise PECs in a wide range obviating problems concerning quasi-degeneracy.

  9. Polarization energy gradients in combined quantum mechanics, effective fragment potential, and polarizable continuum model calculations.

    Science.gov (United States)

    Li, Hui; Gordon, Mark S

    2007-03-28

    A method that combines quantum mechanics (QM), typically a solute, the effective fragment potential (EFP) discrete solvent model, and the polarizable continuum model is described. The EFP induced dipoles and polarizable continuum model (PCM) induced surface charges are determined in a self-consistent fashion. The gradients of these two energies with respect to molecular coordinate changes are derived and implemented. In general, the gradients can be formulated as simple electrostatic forces and torques among the QM nuclei, electrons, EFP static multipoles, induced dipoles, and PCM induced charges. Molecular geometry optimizations can be performed efficiently with these gradients. The formulas derived for EFPPCM can be generally applied to other combined molecular mechanics and continuum methods that employ induced dipoles and charges.

  10. The geothermal energy potential in Denmark - updating the database and new structural and thermal models

    Science.gov (United States)

    Nielsen, Lars Henrik; Sparre Andersen, Morten; Balling, Niels; Boldreel, Lars Ole; Fuchs, Sven; Leth Hjuler, Morten; Kristensen, Lars; Mathiesen, Anders; Olivarius, Mette; Weibel, Rikke

    2017-04-01

    Knowledge of structural, hydraulic and thermal conditions of the subsurface is fundamental for the planning and use of hydrothermal energy. In the framework of a project under the Danish Research program 'Sustainable Energy and Environment' funded by the 'Danish Agency for Science, Technology and Innovation', fundamental geological and geophysical information of importance for the utilization of geothermal energy in Denmark was compiled, analyzed and re-interpreted. A 3D geological model was constructed and used as structural basis for the development of a national subsurface temperature model. In that frame, all available reflection seismic data were interpreted, quality controlled and integrated to improve the regional structural understanding. The analyses and interpretation of available relevant data (i.e. old and new seismic profiles, core and well-log data, literature data) and a new time-depth conversion allowed a consistent correlation of seismic surfaces for whole Denmark and across tectonic features. On this basis, new topologically consistent depth and thickness maps for 16 geological units from the top pre-Zechstein to the surface were drawn. A new 3D structural geological model was developed with special emphasis on potential geothermal reservoirs. The interpretation of petrophysical data (core data and well-logs) allows to evaluate the hydraulic and thermal properties of potential geothermal reservoirs and to develop a parameterized numerical 3D conductive subsurface temperature model. Reservoir properties and quality were estimated by integrating petrography and diagenesis studies with porosity-permeability data. Detailed interpretation of the reservoir quality of the geological formations was made by estimating net reservoir sandstone thickness based on well-log analysis, determination of mineralogy including sediment provenance analysis, and burial history data. New local surface heat-flow values (range: 64-84 mW/m2) were determined for the Danish

  11. Greenhouse crop residues: Energy potential and models for the prediction of their higher heating value

    Energy Technology Data Exchange (ETDEWEB)

    Callejon-Ferre, A.J.; Lopez-Martinez, J.A.; Manzano-Agugliaro, F. [Departamento de Ingenieria Rural, Universidad de Almeria, Ctra. Sacramento s/n, La Canada de San Urbano, 04120 Almeria (Spain); Velazquez-Marti, B. [Departamento de Ingenieria Rural y Agroalimentaria, Universidad Politecnica de Valencia, Camino de Vera s/n, 46022 Valencia (Spain)

    2011-02-15

    Almeria, in southeastern Spain, generates some 1,086,261 t year{sup -1} (fresh weight) of greenhouse crop (Cucurbita pepo L., Cucumis sativus L., Solanum melongena L., Solanum lycopersicum L., Phaseoulus vulgaris L., Capsicum annuum L., Citrillus vulgaris Schrad. and Cucumis melo L.) residues. The energy potential of this biomass is unclear. The aim of the present work was to accurately quantify this variable, differentiating between crop species while taking into consideration the area they each occupy. This, however, required the direct analysis of the higher heating value (HHV) of these residues, involving very expensive and therefore not commonly available equipment. Thus, a further aim was to develop models for predicting the HHV of these residues, taking into account variables measured by elemental and/or proximate analysis, thus providing an economically attractive alternative to direct analysis. All the analyses in this work involved the use of worldwide-recognised standards and methods. The total energy potential for these plant residues, as determined by direct analysis, was 1,003,497.49 MW h year{sup -1}. Twenty univariate and multivariate equations were developed to predict the HHV. The R{sup 2} and adjusted R{sup 2} values obtained for the univariate and multivariate models were 0.909 and 0.946 or above respectively. In all cases, the mean absolute percentage error varied between 0.344 and 2.533. These results show that any of these 20 equations could be used to accurately predict the HHV of crop residues. The residues produced by the Almeria greenhouse industry would appear to be an interesting source of renewable energy. (author)

  12. Solutions of the Klein-Gordon equation with the Morse potential energy model in higher spatial dimensions

    Science.gov (United States)

    Xie, Xiang-Jun; Jia, Chun-Sheng

    2015-03-01

    We solve the Klein-Gordon equation with the Morse potential energy model to obtain the relativistic bound state energy equation in D spatial dimensions. We find that the inter-dimensional degeneracy symmetry exists for the molecular system represented by the Morse potential model. For a fixed vibrational quantum number and various rotational quantum numbers, the relativistic energies for the X1Σ+ state of the ScI molecule diverge as D increases. We observe that the behavior of the relativistic vibrational energies in higher dimensions remains similar to that of the three-dimensional system.

  13. CMB and BAO constraints for an induced gravity dark energy model with a quartic potential

    CERN Document Server

    Umiltà, Caterina; Finelli, Fabio; Paoletti, Daniela

    2015-01-01

    We study the predictions for structure formation in an induced gravity dark energy model with a quartic potential. By developing a dedicated Einstein-Boltzmann code, we study self-consistently the dynamics of homogeneous cosmology and of linear perturbations without using any parametrization. By evolving linear perturbations with initial conditions in the radiation era, we accurately recover the quasi-static analytic approximation in the matter dominated era. We use Planck 2013 data and a compilation of baryonic acoustic oscillation (BAO) data to constrain the coupling $\\gamma$ to the Ricci curvature and the other cosmological parameters. By connecting the gravitational constant in the Einstein equation to the one measured in a Cavendish-like experiment, we find $\\gamma < 0.0012$ at 95% CL with Planck 2013 and BAO data. This is the tightest cosmological constraint on $\\gamma$ and on the corresponding derived post-Newtonian parameters. Because of a degeneracy between $\\gamma$ and the Hubble constant $H_0$, ...

  14. Quantum models with energy-dependent potentials solvable in terms of exceptional orthogonal polynomials

    Science.gov (United States)

    Schulze-Halberg, Axel; Roy, Pinaki

    2017-03-01

    We construct energy-dependent potentials for which the Schrödinger equations admit solutions in terms of exceptional orthogonal polynomials. Our method of construction is based on certain point transformations, applied to the equations of exceptional Hermite, Jacobi and Laguerre polynomials. We present several examples of boundary-value problems with energy-dependent potentials that admit a discrete spectrum and the corresponding normalizable solutions in closed form.

  15. Quantum models with energy-dependent potentials solvable in terms of exceptional orthogonal polynomials

    Energy Technology Data Exchange (ETDEWEB)

    Schulze-Halberg, Axel, E-mail: axgeschu@iun.edu [Department of Mathematics and Actuarial Science, Indiana University Northwest, 3400 Broadway, Gary IN 46408 (United States); Department of Physics, Indiana University Northwest, 3400 Broadway, Gary IN 46408 (United States); Roy, Pinaki, E-mail: pinaki@isical.ac.in [Physics and Applied Mathematics Unit, Indian Statistical Institute, Kolkata 700108 (India)

    2017-03-15

    We construct energy-dependent potentials for which the Schrödinger equations admit solutions in terms of exceptional orthogonal polynomials. Our method of construction is based on certain point transformations, applied to the equations of exceptional Hermite, Jacobi and Laguerre polynomials. We present several examples of boundary-value problems with energy-dependent potentials that admit a discrete spectrum and the corresponding normalizable solutions in closed form.

  16. Modeling irrigation networks for the quantification of potential energy recovering: a case study

    OpenAIRE

    Modesto Pérez-Sánchez; Francisco Javier Sánchez-Romero; Helena M. Ramos; P. Amparo López-Jiménez

    2016-01-01

    Water irrigation systems are required to provide adequate pressure levels in any sort of network. Quite frequently, this requirement is achieved by using pressure reducing valves (PRVs). Nevertheless, the possibility of using hydraulic machines to recover energy instead of PRVs could reduce the energy footprint of the whole system. In this research, a new methodology is proposed to help water managers quantify the potential energy recovering of an irrigation water network with adequate condit...

  17. Empirical valence bond models for reactive potential energy surfaces: a parallel multilevel genetic program approach.

    Science.gov (United States)

    Bellucci, Michael A; Coker, David F

    2011-07-28

    We describe a new method for constructing empirical valence bond potential energy surfaces using a parallel multilevel genetic program (PMLGP). Genetic programs can be used to perform an efficient search through function space and parameter space to find the best functions and sets of parameters that fit energies obtained by ab initio electronic structure calculations. Building on the traditional genetic program approach, the PMLGP utilizes a hierarchy of genetic programming on two different levels. The lower level genetic programs are used to optimize coevolving populations in parallel while the higher level genetic program (HLGP) is used to optimize the genetic operator probabilities of the lower level genetic programs. The HLGP allows the algorithm to dynamically learn the mutation or combination of mutations that most effectively increase the fitness of the populations, causing a significant increase in the algorithm's accuracy and efficiency. The algorithm's accuracy and efficiency is tested against a standard parallel genetic program with a variety of one-dimensional test cases. Subsequently, the PMLGP is utilized to obtain an accurate empirical valence bond model for proton transfer in 3-hydroxy-gamma-pyrone in gas phase and protic solvent.

  18. Rapid energy modeling for existing buildings: Testing the business and environmental potential through an experiment at Autodesk

    Energy Technology Data Exchange (ETDEWEB)

    Deodhar, Aniruddha; Stewart, Emma; Young, Rahul; Khan, Haider

    2010-09-15

    Retrofits of existing buildings represent a huge, growing market and an opportunity to achieve some of the most sizable and cost-effective carbon reductions in any sector of the economy. More 'zero energy' and 'carbon neutral' buildings are being conceived daily by combining energy efficiency measures with renewable energy technologies. However, for all the progress, the building industry faces technical and cost challenges in identifying the highest potential retrofit candidates. This presentation investigates one potential solution, a technology driven workflow called rapid energy modeling, to accelerate and scale the process of analyzing performance for existing buildings in prioritizing improvements.

  19. Community Energy Companies in the UK: A Potential Model for Sustainable Development in “Local” Energy?

    Directory of Open Access Journals (Sweden)

    Séverine Saintier

    2017-07-01

    Full Text Available The rise of renewable energy sources (RES comes with a shift in attention from government and market energy governance to local community initiatives and self-regulation. Although this shift is generally welcome at domestic and EU level, the regulatory dimension, at both levels, is nevertheless not adapted to this multi-actor market since prosumers are not empowered and energy justice is far from achieved. The rise, in the UK, of Community Interest Companies (consumers and local actors’ collectives in the energy sector provides an interesting perspective as it allows a whole system’s view. Research was conducted with six energy community organizations in the South West of England in order to evaluate their role and identity and assess whether this exemplar of “the rise of a social sphere in regulation” could be used as a model for a more sustainable social approach to the governance of economic relations. Findings illustrate that such organizations undoubtedly play an important role in the renewable energy sector and they also help to alleviate some aspects of “energy injustice”. Yet, the failure to recognize, in terms of energy policy, at domestic and EU level, the importance of such actors undermines their role. The need to embed and support such organizations in policy is necessary if one is to succeed to put justice at the core of the changing energy landscape.

  20. Modeling the elastic energy of alloys: Potential pitfalls of continuum treatments

    Science.gov (United States)

    Baskaran, Arvind; Ratsch, Christian; Smereka, Peter

    2015-12-01

    Some issues that arise when modeling elastic energy for binary alloys are discussed within the context of a Keating model and density-functional calculations. The Keating model is a simplified atomistic formulation based on modeling elastic interactions of a binary alloy with harmonic springs whose equilibrium length is species dependent. It is demonstrated that the continuum limit for the strain field are the usual equations of linear elasticity for alloys and that they correctly capture the coarse-grained behavior of the displacement field. In addition, it is established that Euler-Lagrange equation of the continuum limit of the elastic energy will yield the same strain field equation. This is the same energy functional that is often used to model elastic effects in binary alloys. However, a direct calculation of the elastic energy atomistic model reveals that the continuum expression for the elastic energy is both qualitatively and quantitatively incorrect. This is because it does not take atomistic scale compositional nonuniformity into account. Importantly, this result also shows that finely mixed alloys tend to have more elastic energy than segregated systems, which is the exact opposite of predictions made by some continuum theories. It is also shown that for strained thin films the traditionally used effective misfit for alloys systematically underestimate the strain energy. In some models, this drawback is handled by including an elastic contribution to the enthalpy of mixing, which is characterized in terms of the continuum concentration. The direct calculation of the atomistic model reveals that this approach suffers serious difficulties. It is demonstrated that elastic contribution to the enthalpy of mixing is nonisotropic and scale dependent. It is also shown that such effects are present in density-functional theory calculations for the Si-Ge system. This work demonstrates that it is critical to include the microscopic arrangements in any elastic

  1. Modelling of Energy Flow, Rotational Grazing and Potential Productivity in an Alpine Meadow Grazing Ecosystem

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    An eight-compartment model of the energy dynamics of an alpine meadow-sheep grazing ecosystem was proposed based on SHIYOMI's system approach. The compartments were the above-ground plant portion, the underground live portion including roots, the underground dead portion including roots, the above-ground litter Ⅰ (degradable portion), the above-ground litter Ⅱ (undegradable portion), the sheep intake, the sheep liveweight, and the faeces. Energy flows between the eight compartments were described by eight simultaneous differential equations. All parameters in the model were determined from paddock experiments.The model was designed to provide a practical method for estimating the effects of the number of rotational grazing subplots, grazing period, and grazing pressure on the performance of grazing systems for perennial alpine meadow pasture. The model provides at least 28 different attributes for characterizing the performance of the grazing system. Analyses of 270 simulated rotational grazing systems of summer-autumn meadow pasture (grazing from 1st June to 30 October each year) provided an inference base to support two recommendations concerning management variables. First, with a three-paddock, 29-day grazing period and 30.14kJ·m-2·day-1 grazing pressure scheme, the system has the highest total grazing intake, 4250.44 kJ·m-2, during the grazing season. Secondly, with a three-paddock, 7-day grazing period and 28.89kJ·m-2·day-1 grazing pressure scheme, the accumulated graze is 4073.34kJ*m-2.The potential productivity of the alpine meadow under grazing is defined in this paper as the maximal dry biomass of herbage grazed by the grazing animals over the whole growing season. It has been analysed by applying optimal control theory to the model. The productivity is regarded as the objective function to be maximized through optimization of the time course of the grazing pressure, the control variable. The results show that: (1) under constant grazing pressure

  2. Potential energy surfaces and approximate kinetic model for the excited state dynamics of Pigment Yellow 101

    NARCIS (Netherlands)

    Fletcher, Katharyn; Dreuw, Andreas; Faraji, Shirin

    2014-01-01

    Pigment Yellow 101 (PY101) exhibits a rich photochemistry in its S-1 state as it undergoes excited state intramolecular proton transfer and trans-cis isomerizations upon photoexcitation. Relaxed scans of its potential energy surface are thus computed along the reaction paths connecting the six most

  3. Spectroscopy of mesons and proton binding energy in the statistical model with three-quarkonium potentials

    Energy Technology Data Exchange (ETDEWEB)

    Ikhdair, S.M.; Sever, R.; Magdy, M.A. [Middle East Technical Univ., Ankara (Turkey)

    1994-04-01

    The mass spectra of the lowest S, P and D levels of the self-conjugate (Q{bar Q}) and the non-self-conjugate (Q{bar q}) mesons are studied with the three flavour-dependent static quark-antiquark potentials, belong to the class U(r)=a{sub 1}r{sup {gamma}}{minus}a{sub 2}r{sup {minus}{gamma}}+a{sub 3}, for {gamma}=1, 1/2, 3/4 cases. The non-relativistic form of statistical model is used in the calculations. The leptonic decay widths and decay constants of the vector Q{bar Q} and the psuedoscalar Q{bar q} mesons are estimated by considering the improved version of the Van Royen-Weisskopf formula. Moreover, the binding energy, the form factor and the charge radius of the proton have also been calculated. These results are in reasonably good agreement with experimental and theoretical findings. 21 refs., 6 tabs.

  4. Bound state energies and wave functions of spherical quantum dots in presence of a confining potential model

    CERN Document Server

    Ikhdair, Sameer M

    2011-01-01

    We obtain the exact energy spectra and corresponding wave functions of the radial Schr\\"odinger equation (RSE) for any (n,l) state in the presence of a combination of psudoharmonic, Coulomb and linear confining potential terms using an exact analytical iteration method. The interaction potential model under consideration is Cornell-modified plus harmonic (CMpH) type which is a correction form to the harmonic, Coulomb and linear confining potential terms. It is used to investigates the energy of electron in spherical quantum dot and the heavy quarkonia (QQ-onia).

  5. Modeling of In-stream Tidal Energy Development and its Potential Effects in Tacoma Narrows, Washington, USA

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Zhaoqing; Wang, Taiping; Copping, Andrea E.; Geerlofs, Simon H.

    2014-10-01

    Understanding and providing proactive information on the potential for tidal energy projects to cause changes to the physical system and to key water quality constituents in tidal waters is a necessary and cost-effective means to avoid costly regulatory involvement and late stage surprises in the permitting process. This paper presents a modeling study for evaluating the tidal energy extraction and its potential impacts on the marine environment in a real world site - Tacoma Narrows of Puget Sound, Washington State, USA. An unstructured-grid coastal ocean model, fitted with a module that simulates tidal energy devices, was applied to simulate the tidal energy extracted by different turbine array configurations and the potential effects of the extraction at local and system-wide scales in Tacoma Narrows and South Puget Sound. Model results demonstrated the advantage of an unstructured-grid model for simulating the far-field effects of tidal energy extraction in a large model domain, as well as assessing the near-field effect using a fine grid resolution near the tidal turbines. The outcome shows that a realistic near-term deployment scenario extracts a very small fraction of the total tidal energy in the system and that system wide environmental effects are not likely; however, near-field effects on the flow field and bed shear stress in the area of tidal turbine farm are more likely. Model results also indicate that from a practical standpoint, hydrodynamic or water quality effects are not likely to be the limiting factor for development of large commercial-scale tidal farms. Results indicate that very high numbers of turbines are required to significantly alter the tidal system; limitations on marine space or other environmental concerns are likely to be reached before reaching these deployment levels. These findings show that important information obtained from numerical modeling can be used to inform regulatory and policy processes for tidal energy development.

  6. A model for predicting the potential diffusion of solar energy systems in complex urban environments

    Energy Technology Data Exchange (ETDEWEB)

    La Gennusa, Maria; Lascari, Giovanni; Rizzo, Gianfranco; Scaccianoce, Gianluca [Dipartimento dell' Energia, Universita degli Studi di Palermo, Viale delle Scienze - Building 9, 90128 Palermo (Italy); Sorrentino, Giancarlo, E-mail: sorrentino@dream.unipa.it [Dipartimento dell' Energia, Universita degli Studi di Palermo, Viale delle Scienze - Building 9, 90128 Palermo (Italy)

    2011-09-15

    The necessity to reduce greenhouse gases emission produced by energy building consumptions and to cut the energy bill (mainly due to the use of fossil sources) leads to the employment of renewable energy sources in new planned scenarios. In particular, more and more often municipal energy and environmental plans pay great attention to the possibilities of employment of the solar technologies at urban scale. Solar thermal and photovoltaic (PV) systems are, by far, the most suitable tools to be utilized in urban areas. Obviously, the proper adoption of such systems in buildings does call for the availability of calculation methods suitable to provide the actual level of exploitation of solar energy in urban layouts. In this work, a procedure for evaluating the geographical energy potential of building roofs in urban areas is proposed; in particular, the amount of surface on the roof that could be used for the installation of systems able to capture solar radiation for the energy production is investigated. The proposed procedure is based on the use of the GIS technology and 3D cartography. The effectiveness of the proposed method is assessed by means of an application to the town of Palermo (Italy). - Highlights: > The GIS techniques allow to analyze various future scenarios about urban planning. > We propose a procedure for assessing the extension of superficial urban areas useable for the installation of solar systems. > This procedure allow to compile a scale of priority of intervention. > The cost for financing such interventions is compared to the penalty to pay for not achieving the Kyoto goals.

  7. Potential energy savings

    DEFF Research Database (Denmark)

    Schultz, Jørgen Munthe

    1996-01-01

    The background for the simulations of annual energy consumption and indoor temperature level is described.......The background for the simulations of annual energy consumption and indoor temperature level is described....

  8. Generalized Extreme Value Distribution Models for the Assessment of Seasonal Wind Energy Potential of Debuncha, Cameroon

    Directory of Open Access Journals (Sweden)

    Nkongho Ayuketang Arreyndip

    2016-01-01

    Full Text Available The method of generalized extreme value family of distributions (Weibull, Gumbel, and Frechet is employed for the first time to assess the wind energy potential of Debuncha, South-West Cameroon, and to study the variation of energy over the seasons on this site. The 29-year (1983–2013 average daily wind speed data over Debuncha due to missing values in the years 1992 and 1994 is gotten from NASA satellite data through the RETScreen software tool provided by CANMET Canada. The data is partitioned into min-monthly, mean-monthly, and max-monthly data and fitted using maximum likelihood method to the two-parameter Weibull, Gumbel, and Frechet distributions for the purpose of determining the best fit to be used for assessing the wind energy potential on this site. The respective shape and scale parameters are estimated. By making use of the P values of the Kolmogorov-Smirnov statistic (K-S and the standard error (s.e analysis, the results show that the Frechet distribution best fits the min-monthly, mean-monthly, and max-monthly data compared to the Weibull and Gumbel distributions. Wind speed distributions and wind power densities of both the wet and dry seasons are compared. The results show that the wind power density of the wet season was higher than in the dry season. The wind speeds at this site seem quite low; maximum wind speeds are listed as between 3.1 and 4.2 m/s, which is below the cut-in wind speed of many modern turbines (6–10 m/s. However, we recommend the installation of low cut-in wind turbines like the Savonius or Aircon (10 KW for stand-alone low energy need.

  9. California Industrial Energy Efficiency Potential

    Energy Technology Data Exchange (ETDEWEB)

    Coito, Fred; Worrell, Ernst; Price, Lynn; Masanet, Eric; RafaelFriedmann; Rufo, Mike

    2005-06-01

    This paper presents an overview of the modeling approach andhighlights key findings of a California industrial energy efficiencypotential study. In addition to providing estimates of technical andeconomic potential, the study examines achievable program potential undervarious program-funding scenarios. The focus is on electricity andnatural gas savings for manufacturing in the service territories ofCalifornia's investor-owned utilities (IOUs). The assessment is conductedby industry type and by end use. Both crosscutting technologies andindustry-specific process measures are examined. Measure penetration intothe marketplace is modeled as a function of customer awareness, measurecost effectiveness, and perceived market barriers. Data for the studycomes from a variety of sources, including: utility billing records, theEnergy Information Association (EIA) Manufacturing Energy ConsumptionSurvey (MECS), state-sponsored avoided cost studies, energy efficiencyprogram filings, and technology savings and cost data developed throughLawrence Berkeley National Laboratory (LBNL). The study identifies 1,706GWh and 47 Mth (million therms) per year of achievable potential over thenext twelve years under recent levels of program expenditures, accountingfor 5.2 percent of industrial electricity consumption and 1.3 percent ofindustrial natural gas consumption. These estimates grow to 2,748 GWh and192 Mth per year if all cost-effective and achievable opportunities arepursued. Key industrial electricity end uses, in terms of energy savingspotential, include compressed air and pumping systems that combine toaccount for about half of the total achievable potential estimates. Fornatural gas, savings are concentrated in the boiler and process heatingend uses, accounting for over 99 percent to total achievablepotential.

  10. California Industrial Energy Efficiency Potential

    Energy Technology Data Exchange (ETDEWEB)

    Coito, Fred; Worrell, Ernst; Price, Lynn; Masanet, Eric; RafaelFriedmann; Rufo, Mike

    2005-06-01

    This paper presents an overview of the modeling approach andhighlights key findings of a California industrial energy efficiencypotential study. In addition to providing estimates of technical andeconomic potential, the study examines achievable program potential undervarious program-funding scenarios. The focus is on electricity andnatural gas savings for manufacturing in the service territories ofCalifornia's investor-owned utilities (IOUs). The assessment is conductedby industry type and by end use. Both crosscutting technologies andindustry-specific process measures are examined. Measure penetration intothe marketplace is modeled as a function of customer awareness, measurecost effectiveness, and perceived market barriers. Data for the studycomes from a variety of sources, including: utility billing records, theEnergy Information Association (EIA) Manufacturing Energy ConsumptionSurvey (MECS), state-sponsored avoided cost studies, energy efficiencyprogram filings, and technology savings and cost data developed throughLawrence Berkeley National Laboratory (LBNL). The study identifies 1,706GWh and 47 Mth (million therms) per year of achievable potential over thenext twelve years under recent levels of program expenditures, accountingfor 5.2 percent of industrial electricity consumption and 1.3 percent ofindustrial natural gas consumption. These estimates grow to 2,748 GWh and192 Mth per year if all cost-effective and achievable opportunities arepursued. Key industrial electricity end uses, in terms of energy savingspotential, include compressed air and pumping systems that combine toaccount for about half of the total achievable potential estimates. Fornatural gas, savings are concentrated in the boiler and process heatingend uses, accounting for over 99 percent to total achievablepotential.

  11. Estimation of Energy Potential from Organic Fractions of Municipal Solid Waste by Using Empirical Models at Hyderabad, Pakistan.

    Directory of Open Access Journals (Sweden)

    Muhammad Safar Korai

    2016-01-01

    Full Text Available MSW (Municipal Solid Waste now-a-day is considered as a precious renewable energy resource for various purposes. In view of above fact, one hundred samples of MSW were collected from different locations of study area. Quantities of each organic waste component were determined by using physical balance and also their proximate analysis was performed by using oven and muffle furnace. In this study, nine empirical models were used for estimating the energy value in terms of heat from OFMSW (Organic Fractions of Municipal Solid Waste, namely two of them were based upon physical composition, four of them were on the basis of its proximate analysis and remaining three of them was according to ultimate analysis of OFMSW. From comparison of all energy models, the empirical Model No. 3 and No. 4 based upon proximate analysis have highest energy recovery potential than all of others. Moreover, the result of Model No.3 on the basis of proximate analysis is closer to the calorific value of mixed OFMSW than the values obtained by rest of models. Therefore, this is the best model to be used. From the outcomes of this study it can be realized that the energy recovery from the OFMSW plays a vital role for economical growth of the country. On that account, a systematic approach should be performed in detail before making a decision on such option

  12. Assessment of the GHG reduction potential from energy crops using a combined LCA and biogeochemical process models: a review.

    Science.gov (United States)

    Jiang, Dong; Hao, Mengmeng; Fu, Jingying; Wang, Qiao; Huang, Yaohuan; Fu, Xinyu

    2014-01-01

    The main purpose for developing biofuel is to reduce GHG (greenhouse gas) emissions, but the comprehensive environmental impact of such fuels is not clear. Life cycle analysis (LCA), as a complete comprehensive analysis method, has been widely used in bioenergy assessment studies. Great efforts have been directed toward establishing an efficient method for comprehensively estimating the greenhouse gas (GHG) emission reduction potential from the large-scale cultivation of energy plants by combining LCA with ecosystem/biogeochemical process models. LCA presents a general framework for evaluating the energy consumption and GHG emission from energy crop planting, yield acquisition, production, product use, and postprocessing. Meanwhile, ecosystem/biogeochemical process models are adopted to simulate the fluxes and storage of energy, water, carbon, and nitrogen in the soil-plant (energy crops) soil continuum. Although clear progress has been made in recent years, some problems still exist in current studies and should be addressed. This paper reviews the state-of-the-art method for estimating GHG emission reduction through developing energy crops and introduces in detail a new approach for assessing GHG emission reduction by combining LCA with biogeochemical process models. The main achievements of this study along with the problems in current studies are described and discussed.

  13. A phenomenological model to study the energy discrimination potential of GEM detectors in the X-ray range

    Energy Technology Data Exchange (ETDEWEB)

    Causa, F., E-mail: federica.causa@enea.it; Pacella, D.; Romano, A.; Claps, G.; Gabellieri, L.

    2015-11-01

    An empirical model is presented to study the operational characteristics of GEM detectors in the X-ray range and, in particular, its energy discrimination potential. Physical processes are modelled from a macroscopic point of view, to provide a simple but effective simulation tool. Experimental data from monochromatic and combined, two-line fluorescence sources, are used to validate the model and provide realistic estimates of the empirical parameters used in the description. The model is instrumental in understanding the role of threshold, gain and operational conditions to achieve energy-discriminating response. Appropriate choices of gas mixtures, threshold and gain will permit to best utilise this new functionality of the GEM to improve the efficiency of image detectors in applications ranging from in-situ imaging in harsh environments, such as tokamaks, to composite materials analysis and medical imaging of tissues.

  14. Molecular calculations of excitation energies and (hyper)polarizabilities with a statistical average of orbital model exchange-correlation potentials

    Science.gov (United States)

    Schipper, P. R. T.; Gritsenko, O. V.; van Gisbergen, S. J. A.; Baerends, E. J.

    2000-01-01

    An approximate Kohn-Sham exchange-correlation potential νxcSAOP is developed with the method of statistical averaging of (model) orbital potentials (SAOP) and is applied to the calculation of excitation energies as well as of static and frequency-dependent multipole polarizabilities and hyperpolarizabilities within time-dependent density functional theory (TDDFT). νxcSAOP provides high quality results for all calculated response properties and a substantial improvement upon the local density approximation (LDA) and the van Leeuwen-Baerends (LB) potentials for the prototype molecules CO, N2, CH2O, and C2H4. For the first three molecules and the lower excitations of the C2H4 the average error of the vertical excitation energies calculated with νxcSAOP approaches the benchmark accuracy of 0.1 eV for the electronic spectra.

  15. Potential energy savings

    DEFF Research Database (Denmark)

    Schultz, Jørgen Munthe; Chevalier, B.

    1996-01-01

    Four different building models are described. The buildings are a single family house and a centrally located flat in a multi storey building located in Denmark and France (Nice) respectively. The buildings are built according to the Danish respectively the French building code....

  16. Potential energy savings

    DEFF Research Database (Denmark)

    Schultz, Jørgen Munthe; Chevalier, B.

    1996-01-01

    Four different building models are described - two from France and two from Denmark. For each country a single family house and a centrally located flat in a multi storey building have been chosen. The buildings is built according to the French and the Danish building code respectively...

  17. Decadal predictability of wind energy potentials over Germany in the Earth System Model of the Max-Planck-Institute

    Science.gov (United States)

    Moemken, Julia; Reyers, Mark; Pinto, Joaquim G.

    2015-04-01

    Regional climate predictions on timescales from one year to one decade are gaining importance since this time frame falls within the planning horizon of politics, economy, and society. In this context, decadal predictions are of particular interest for the development of renewable energies such as wind energy. The present study examines the decadal predictability of wind energy potentials in the framework of the ongoing MiKlip consortium (www.fona-miklip.de). This consortium aims to develop a model system based on the Max-Planck-Institute Earth System Model (MPI-ESM), that can provide skillful decadal predictions on regional and global scales. Three generations of the decadal prediction system of the MPI-ESM are analysed here with respect to wind energy potentials on the regional and local scale. Ensembles of uninitialized historical and yearly initialized hindcast experiments are used to assess the forecast skill for wind energy output (Eout) over Central Europe, with special focus given to Germany. With this aim, a statistical-dynamical downscaling (SDD) approach is used for the regionalisation of the global datasets. All three MPI-ESM ensemble generations, which are based on different hindcast initialisations, show some forecast skill for wind energy potentials on yearly and multi-yearly time scales over Germany, Poland, Czech Republic and Benelux. In general, the predictive skill for the two latest MPI-ESM generations (baseline1 and prototype) is higher than for the first generation (baseline0). The predictability varies with different leading-time periods and declines with increasing time since initialisation. Regarding seasonal means, skill scores are lowest during winter, and persist longest for autumn in all three generations. In the summer months, differences between the three generations are more pronounced than for the other seasons. In general, forecast skill for wind energy potential is found for all three MPI-ESM ensemble generations. This skill is

  18. LHC Physics Potential versus Energy

    Energy Technology Data Exchange (ETDEWEB)

    Quigg, Chris; /Fermilab

    2009-08-01

    Parton luminosities are convenient for estimating how the physics potential of Large Hadron Collider experiments depends on the energy of the proton beams. I present parton luminosities, ratios of parton luminosities, and contours of fixed parton luminosity for gg, u{bar d}, and qq interactions over the energy range relevant to the Large Hadron Collider, along with example analyses for specific processes.

  19. Models for residential- and commercial-sector energy-conservation analysis: applications, limitations, and future potential. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Cole, Henry E.; Fullen, Robert E.

    1980-09-01

    This report reviews four of the major models used by the Department of Energy (DOE) for energy conservation analyses in the residential- and commercial-building sectors. The objective is to provide a critical analysis of how these models can serve as tools for DOE and its Conservation Policy Office in evaluating and quantifying their policy and program requirements. For this, the study brings together information on the models' analytical structure and their strengths and limitations in policy applications these are then employed to assess the most-effective role for each model in addressing future issues of buildings energy-conservation policy and analysis. The four models covered are: Oak Ridge Residential Energy Model; Micro Analysis of Transfers to Households/Comprehensive Human Resources Data System (MATH/CHRDS) Model; Oak Ridge Commercial Energy Model; and Brookhaven Buildings Energy Conservation Optimization Model (BECOM).

  20. Nuclear flux densities during a model pericyclic reaction with energies well above and below the potential barrier.

    Science.gov (United States)

    Bredtmann, Timm; Kono, Hirohiko; Manz, Jörn; Nakamura, Kosuke; Stemmle, Christian

    2013-05-10

    Pericyclic reactions with energies E well above the potential energy barrier B (case E>B) proceed with quantum nuclear flux densities 〈j〉 which are essentially proportional to the nuclear densities ρ in the femtosecond time domain. This corresponds to the definition of classical (cl) mechanics, j(cl)=υ(cl) ρ(cl), with almost constant velocity v(cl). For the other case Evalue close to the barrier where ρ is a minimum (in fact where ρ is close to zero). The general conclusion is that quantum mechanical nuclear flux densities may be at variance from traditional expectations based on classical trajectories. This prediction calls for experimental demonstration. The counter-intuitive proof-of-principle is demonstrated for a simple, one-dimensional model of the Cope rearrangement of semibullvalene. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Assessment of wind energy potential in China

    Institute of Scientific and Technical Information of China (English)

    Zhu Rong; Zhang De; Wang Yuedong; Xing Xuhuang; Li Zechun

    2009-01-01

    China wind atlas was made by numerical simulation and the wind energy potential in China was calculated. The model system for wind energy resource assessment was set up based on Canadian Wind Energy Simulating Toolkit (WEST) and the simulating method was as follows. First, the weather classes were obtained depend on meteorological data of 30 years. Then, driven by the initial meteorological field produced by each weather class, the meso-scale model ran for the distribution of wind energy resources according each weather class condition one by one. Finally, averaging all the modeling output weighted by the occurrence frequency of each weather class, the annual mean distribution of wind energy resources was worked out. Compared the simulated wind energy potential with other results from several ac-tivities and studies for wind energy resource assessment, it is found that the simulated wind energy potential in mainland of China is 3 times that from the second and the third investigations for wind energy resources by CMA, and is similar to the wind energy potential obtained by NREL in Solar and Wind Energy Resource Assessment (SWERA) project. The simulated offshore wind energy potential of China seems smaller than the true value. According to the simulated results of CMA and considering lots of limited factors to wind energy development, the final conclusion can be obtained that the wind energy availability in China is 700~1 200 GW, in which 600~1 000 GW is in mainland and 100~200 GW is on offshore, and wind power will become the important part of energy composition in future.

  2. World potential of renewable energies

    Energy Technology Data Exchange (ETDEWEB)

    Dessus, B.; Devin, B.; Pharabod, F.

    1991-07-01

    A comprehensive analysis, region by region, of the actually accessible renewable energies at a given horizon, is presented. The same methodology as the one employed to derive ``proven fossil energy reserves`` from ``energy resources`` is adopted, in which resources are defined by quantitative information on physical potential, while reserves take into account technical and economical accessibility. As renewable resources are fluctuating with time and are diluted in space and not readily transportable or storeable, it is necessary to consider the presence of populations or activities near enough to be able to profit by these diluted and volatile energies.

  3. Relativity, potential energy, and mass

    Science.gov (United States)

    Hecht, Eugene

    2016-11-01

    This paper is an exploration of the concept of energy, illuminated by the transformative insights of the special theory of relativity. Focusing on potential energy (PE), it will be shown that PE as presently defined is in conflict with the tenets of special relativity. Even though PE remains an indispensable theoretical device its actual physicality is questionable. Moreover its ontological status is quite different from that of both kinetic energy and mass, a significant point that is not widely appreciated. We will establish that PE is a theoretical concept as opposed to an empirical one; it is a descriptor of mass-energy without a detectable physical presence of its own. PE is a measure of energy stored, it is not the energy stored.

  4. Energy modelling software

    CSIR Research Space (South Africa)

    Osburn, L

    2010-01-01

    Full Text Available The construction industry has turned to energy modelling in order to assist them in reducing the amount of energy consumed by buildings. However, while the energy loads of buildings can be accurately modelled, energy models often under...

  5. Assessment of triton potential energy

    CERN Document Server

    Friar, J L

    1996-01-01

    An assessment is made of the dominant features contributing to the triton potential energy, with the objective of understanding qualitatively their origins and sensitivities. Relativistic effects, short-range repulsion, and OPEP dominance are discussed. A determination of the importance of various regions of nucleon-nucleon separation is made numerically.

  6. Assessment of Triton Potential Energy

    Science.gov (United States)

    Friar, J. L.; Payne, G. L.

    1995-12-01

    An assessment is made of the dominant features contributing to the triton potential energy, with the objective of understanding qualitatively their origins and sensitivities. Relativistic effects, short-range repulsion, and OPEP dominance are discussed. A determination of the importance of various regions of nucleon-nucleon separation is made numerically.

  7. The potential of renewable energy

    Energy Technology Data Exchange (ETDEWEB)

    1990-03-01

    On June 27 and 28, 1989, the US Department of Energy (DOE) national laboratories were convened to discuss plans for the development of a National Energy Strategy (NES) and, in particular, the analytic needs in support of NES that could be addressed by the laboratories. As a result of that meeting, interlaboratory teams were formed to produce analytic white papers on key topics, and a lead laboratory was designated for each core laboratory team. The broad-ranging renewables assignment is summarized by the following issue statement from the Office of Policy, Planning and Analysis: to what extent can renewable energy technologies contribute to diversifying sources of energy supply What are the major barriers to greater renewable energy use and what is the potential timing of widespread commercialization for various categories of applications This report presents the results of the intensive activity initiated by the June 1989 meeting to produce a white paper on renewable energy. Scores of scientists, analysts, and engineers in the five core laboratories gave generously of their time over the past eight months to produce this document. Their generous, constructive efforts are hereby gratefully acknowledged. 126 refs., 44 figs., 32 tabs.

  8. Wind Energy Potential in Bangladesh

    Directory of Open Access Journals (Sweden)

    A.Z.A. Saifullah

    2016-07-01

    Full Text Available Bangladesh is encountering difficulties in supplying energy to maintain its economic growth. Government of Bangladesh is looking for renewable energy sources to meet up the total power demand in this country. The present study aims to assess wind energy potential in Bangladesh as a sustainable solution to overcome the energy crisis. Wind speed at six coastal zones Patenga, Cox’s Bazar, Teknaf, Char Fassion, Kuakata and Kutubdia at Bay of Bengal of Bangladesh have been analyzed. A near shore wind farm has been considered at these locations having a coastal line of 574 km. The turbines are spaced 7D apart in the prevailing wind direction, and 3D apart in the perpendicular direction, where D is rotor diameter. This near shore wind farm with an array of 5104 horizontal axis wind turbines with hub height of 100 m and rotor diameter of 75 m with a wind speed of 7 m/sec is capable to generate 1855.25 MW of electrical power. This can mitigate 55.93 per cent of energy shortage in 2016. By developing renewable energy sources it is possible to compensate 11.25 per cent of total power demand by 2020.

  9. Energy Transfer in Scattering by Rotating Potentials

    Indian Academy of Sciences (India)

    Volker Enss; Vadim Kostrykin; Robert Schrader

    2002-02-01

    Quantum mechanical scattering theory is studied for time-dependent Schrödinger operators, in particular for particles in a rotating potential. Under various assumptions about the decay rate at infinity we show uniform boundedness in time for the kinetic energy of scattering states, existence and completeness of wave operators, and existence of a conserved quantity under scattering. In a simple model we determine the energy transferred to a particle by collision with a rotating blade.

  10. Methodology for Analyzing the Technical Potential for Energy Performance in the U.S. Commercial Buildings Sector with Detailed Energy Modeling: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Griffith, B.; Crawley, D.

    2006-11-01

    This paper summarizes a methodology for developing quantitative answers to the question, ''How low can energy use go within the commercial buildings sector''? The basic process is to take each building in the 1999 CBECS public use data files and create a baseline building energy model for it as if it were being built new in 2005 with code-minimum energy performance.

  11. Energy from streaming current and potential

    NARCIS (Netherlands)

    Olthuis, Wouter; Schippers, Bob; Eijkel, Jan C.T.; van den Berg, Albert

    2005-01-01

    It is investigated how much energy can be delivered by a streaming current source. A streaming current and subsequent streaming potential originate when double layer charge is transported by hydrodynamic flow. Theory and a network model of such a source is presented and initial experimental results

  12. Energy recovery potential and life cycle impact assessment of municipal solid waste management technologies in Asian countries using ELP model

    Energy Technology Data Exchange (ETDEWEB)

    Pandyaswargo, Andante Hadi; Onoda, Hiroshi; Nagata, Katsuya [Waseda Univ., Saitama (Japan). Graduate School of Environment and Energy Engineering

    2012-11-01

    Natural resource scarcity and the effects of environmental destruction have pushed societies to use and reuse resources more efficiently. Waste should no longer be seen as a burden but rather as another source of material such as energy fuel. This study analyzes the potential of three waste management technologies - incineration with energy recovery, composting, and sanitary landfill gas collection - as ways to recover energy and material from municipal solid waste. The study applies the environmental load point (ELP) method and utilizes municipal waste characteristics and composition from India, Indonesia, and China as case studies. The ELP methodology employs integrated weighting in the quantification process to get a one-unit result. This study particularly uses analytic hierarchical process questionnaires to get the weighting value of the nine impact categories: energy depletion, global warming, ozone depletion, resource consumption, ecosystem influence, water pollution, waste disposal, air pollution, and acid rain. The results show that the scenario which includes composting organic waste and sanitary landfill with gas collection for energy recovery has medium environmental impact and the highest practicability. The optimum material and energy potential is from the Chinese case study in which 254 tonnes of compost fertilizer and 60 MWh of electricity is the estimated output for every 1,000 tonnes of waste treated. (orig.)

  13. Cowichan Valley energy mapping and modelling. Report 1 - GIS mapping of potential renewable energy resources in the CVRD. Final report. [Vancouver Island, Canada

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-06-15

    The driving force behind the Integrated Energy Mapping and Analysis project was the identification and analysis of a suite of pathways that the Cowichan Valley Regional District (CVRD) can utilise to increase its energy resilience, as well as reduce energy consumption and GHG emissions, with a primary focus on the residential sector. Mapping and analysis undertaken will support provincial energy and GHG reduction targets, and the suite of pathways outlined will address a CVRD internal target that calls for 75% of the region's energy within the residential sector to come from locally sourced renewables by 2050. The target has been developed as a mechanism to meet resilience and climate action target. The maps and findings produced are to be integrated as part of a regional policy framework currently under development. The first task in the project was the production of a series of thematic GIS maps and associated databases of potential renewable energy resources in the CVRD. The renewable energy sources mapped were solar, wind, micro hydro, and biomass (residues and waste). Other sources were also discussed (e.g. geothermal heat) but not mapped due to lack of spatially explicit input data. The task 1 findings are detailed in this report. (LN)

  14. Estimating Roof Solar Energy Potential in the Downtown Area Using a GPU-Accelerated Solar Radiation Model and Airborne LiDAR Data

    Directory of Open Access Journals (Sweden)

    Yan Huang

    2015-12-01

    Full Text Available Solar energy, as a clean and renewable resource is becoming increasingly important in the global context of climate change and energy crisis. Utilization of solar energy in urban areas is of great importance in urban energy planning, environmental conservation, and sustainable development. However, available spaces for solar panel installation in cities are quite limited except for building roofs. Furthermore, complex urban 3D morphology greatly affects sunlit patterns on building roofs, especially in downtown areas, which makes the determination of roof solar energy potential a challenging task. The object of this study is to estimate the solar radiation on building roofs in an urban area in Shanghai, China, and select suitable spaces for installing solar panels that can effectively utilize solar energy. A Graphic Processing Unit (GPU-based solar radiation model named SHORTWAVE-C simulating direct and non-direct solar radiation intensity was developed by adding the capability of considering cloud influence into the previous SHORTWAVE model. Airborne Light Detection and Ranging (LiDAR data was used as the input of the SHORTWAVE-C model and to investigate the morphological characteristics of the study area. The results show that the SHORTWAVE-C model can accurately estimate the solar radiation intensity in a complex urban environment under cloudy conditions, and the GPU acceleration method can reduce the computation time by up to 46%. Two sites with different building densities and rooftop structures were selected to illustrate the influence of urban morphology on the solar radiation and solar illumination duration. Based on the findings, an object-based method was implemented to identify suitable places for rooftop solar panel installation that can fully utilize the solar energy potential. Our study provides useful strategic guidelines for the selection and assessment of roof solar energy potential for urban energy planning.

  15. Growth potential of blue mussels (M. edulis) exposed to different salinities evaluated by a Dynamic Energy Budget model

    DEFF Research Database (Denmark)

    Maar, Marie; Saurel, Camille; Landes, Anja

    2015-01-01

    For bluemussels,Mytilus edulis, onemajor constrain in the Baltic Sea is the low salinities that reduce the efficiency of mussel production. However, the effects of living in low and variable salinity regimes are rarely considered in models describing mussel growth. The aim of the present study...... was to incorporate the effects of low salinity into an eco-physiological model of blue mussels and to identify areas suitable for mussel production. A Dynamic Energy Budget (DEB) model was modified with respect to i) the morphological parameters (DW/WW-ratio, shape factor), ii) change in ingestion rate and iii...... symptoms or as part of integrated multi-trophic aquaculture production. The model can also be used to predict the effects of salinity changes on mussel populations e.g. in climate change studies...

  16. Wave energy potential in Galicia (NW Spain)

    DEFF Research Database (Denmark)

    Iglesias, Gregorio; López, Mario; Carballo, Rodrigo;

    2009-01-01

    Wave power presents significant advantages with regard to other CO2-free energy sources, among which the predictability, high load factor and low visual and environmental impact stand out. Galicia, facing the Atlantic on the north-western corner of the Iberian Peninsula, is subjected to a very...... harsh wave climate; in this work its potential for energy production is assessed based on three-hourly data from a third generation ocean wave model (WAM) covering the period 1996 - 2005. Taking into account the results of this assessment along with other relevant considerations such as the location...... of ports, navigation routes, and fishing and aquaculture zones, an area is selected for wave energy exploitation. The transformation of the offshore wave field as it propagates into this area is computed by means of a nearshore wave model (SWAN) in order to select the optimum locations for a wave farm. Two...

  17. Learning Potential Energy Landscapes using Graph Kernels

    CERN Document Server

    Ferré, G; Barros, K

    2016-01-01

    Recent machine learning methods make it possible to model potential energy of atomic configurations with chemical-level accuracy (as calculated from ab-initio calculations) and at speeds suitable for molecular dynamics simulation. Best performance is achieved when the known physical constraints are encoded in the machine learning models. For example, the atomic energy is invariant under global translations and rotations; it is also invariant to permutations of same-species atoms. Although simple to state, these symmetries are complicated to encode into machine learning algorithms. In this paper, we present a machine learning approach based on graph theory that naturally incorporates translation, rotation, and permutation symmetries. Specifically, we use a random walk graph kernel to measure the similarity of two adjacency matrices, each of which represents a local atomic environment. We show on a standard benchmark that our Graph Approximated Energy (GRAPE) method is competitive with state of the art kernel m...

  18. Sparse representation for a potential energy surface

    Science.gov (United States)

    Seko, Atsuto; Takahashi, Akira; Tanaka, Isao

    2014-07-01

    We propose a simple scheme to estimate the potential energy surface (PES) for which the accuracy can be easily controlled and improved. It is based on model selection within the framework of linear regression using the least absolute shrinkage and selection operator (LASSO) technique. Basis functions are selected from a systematic large set of candidate functions. The sparsity of the PES significantly reduces the computational cost of evaluating the energy and force in molecular dynamics simulations without losing accuracy. The usefulness of the scheme for describing the elemental metals Na and Mg is clearly demonstrated.

  19. Potential energy landscapes of tetragonal pyramid molecules

    Science.gov (United States)

    Yoshida, Yuichiro; Sato, Hirofumi; Morgan, John W. R.; Wales, David J.

    2016-11-01

    Hiraoka et al. have developed a self-assembling system referred to as a nanocube (Hiraoka et al., 2008). In the present contribution a coarse-grained model for this system is analysed, focusing on how the potential energy landscape for self-assembly is related to the geometry of the building blocks. We find that six molecules assemble to form various clusters, with cubic and sheet structures the most stable. The relative stability is determined by the geometry of the building blocks.

  20. Geothermal Energy: Tapping the Potential

    Science.gov (United States)

    Johnson, Bill

    2008-01-01

    Ground source geothermal energy enables one to tap into the earth's stored renewable energy for heating and cooling facilities. Proper application of ground-source geothermal technology can have a dramatic impact on the efficiency and financial performance of building energy utilization (30%+). At the same time, using this alternative energy…

  1. Biowaste energy potential in Kenya

    NARCIS (Netherlands)

    Nzila, C.; DeWulf, J.; Spanjers, H.; Kiriamiti, H.; Langenhove, H.

    2010-01-01

    Energy affects all aspects of national development. Hence the current global energy crisis demands greater attention to new initiatives on alternative energy sources that are renewable, economically feasible and sustainable. The agriculture-dependent developing countries in Africa can mitigate the e

  2. Renewable energy costs, potentials, barriers: Conceptual issues

    Energy Technology Data Exchange (ETDEWEB)

    Verbruggen, Aviel, E-mail: aviel.verbruggen@ua.ac.b [University of Antwerp (Belgium); Fischedick, Manfred [Wuppertal Institute for Climate, Environment, Energy (Germany); Moomaw, William [Tufts University, Center for International Environment and Resource Policy (United States); Weir, Tony [University of the South Pacific, Fiji Islands (Fiji); Nadai, Alain [Centre International de Recherche sur nvironnement et le Developpement CIRED (France); Nilsson, Lars J. [University of Lund (Sweden); Nyboer, John [Simon Fraser University, School of Resource and Environmental Management (Canada); Sathaye, Jayant [Lawrence Berkeley Laboratory (United States)

    2010-02-15

    Renewable energy can become the major energy supply option in low-carbon energy economies. Disruptive transformations in all energy systems are necessary for tapping widely available renewable energy resources. Organizing the energy transition from non-sustainable to renewable energy is often described as the major challenge of the first half of the 21st century. Technological innovation, the economy (costs and prices) and policies have to be aligned to achieve full renewable energy potentials, and barriers impeding that growth need to be removed. These issues are also covered by IPCC's special report on renewable energy and climate change to be completed in 2010. This article focuses on the interrelations among the drivers. It clarifies definitions of costs and prices, and of barriers. After reviewing how the third and fourth assessment reports of IPCC cover mitigation potentials and commenting on definitions of renewable energy potentials in the literature, we propose a consistent set of potentials of renewable energy supplies.

  3. Energy efficiency potentials and energy management practices in Swedish firms

    OpenAIRE

    Backlund, Sandra; Broberg, Sarah; Ottosson, Mikael; Thollander, Patrik

    2012-01-01

    In order to improve energy efficiency and reach the EU:s 20-20-20 primary energy saving target, focus has mainly been on diffusion of technology. Previous studies have illustrated large untapped energy saving potentials from implementing energy management practices in firms. Energy management practices have large effects on energy utilization and also a short pay-back time. According to these studies, energy management practices also effect investment decisions and the outcome of investments ...

  4. Potential energy surfaces of Polonium isotopes

    Science.gov (United States)

    Nerlo-Pomorska, B.; Pomorski, K.; Schmitt, C.; Bartel, J.

    2015-11-01

    The evolution of the potential energy landscape is analysed in detail for ten even-even polonium isotopes in the mass range 188\\lt A\\lt 220 as obtained within the macroscopic-microscopic approach, relying on the Lublin-Strasbourg drop model and the Yukawa-folded single-particle energies for calculating the microscopic shell and pairing corrections. A variant of the modified Funny-Hills nuclear shape parametrization is used to efficiently map possible fission paths. The approach explains the main features of the fragment partition as measured in low-energy fission along the polonium chain. The latter lies in a transitional region of the nuclear chart, and will be essential to consistently understand the evolution of fission properties from neutron-deficient mercury to heavy actinides. The ability of our method to predict fission observables over such an extended region looks promising.

  5. Potential of renewable and alternative energy sources

    Science.gov (United States)

    Konovalov, V.; Pogharnitskaya, O.; Rostovshchikova, A.; Matveenko, I.

    2015-11-01

    The article deals with application potential of clean alternative renewable energy sources. By means of system analysis the forecast for consumption of electrical energy in Tomsk Oblast as well as main energy sources of existing energy system have been studied up to 2018. Engineering potential of renewable and alternative energy sources is evaluated. Besides, ranking in the order of their efficiency descending is performed. It is concluded that Tomsk Oblast has high potential of alternative and renewable energy sources, among which the most promising development perspective is implementation of gasification stations to save fuel consumed by diesel power stations as well as building wind-power plants.

  6. Energy-consumption modelling

    Energy Technology Data Exchange (ETDEWEB)

    Reiter, E.R.

    1980-01-01

    A highly sophisticated and accurate approach is described to compute on an hourly or daily basis the energy consumption for space heating by individual buildings, urban sectors, and whole cities. The need for models and specifically weather-sensitive models, composite models, and space-heating models are discussed. Development of the Colorado State University Model, based on heat-transfer equations and on a heuristic, adaptive, self-organizing computation learning approach, is described. Results of modeling energy consumption by the city of Minneapolis and Cheyenne are given. Some data on energy consumption in individual buildings are included.

  7. Methanol clusters (CH3OH)n: putative global minimum-energy structures from model potentials and dispersion-corrected density functional theory.

    Science.gov (United States)

    Kazachenko, Sergey; Bulusu, Satya; Thakkar, Ajit J

    2013-06-14

    Putative global minima are reported for methanol clusters (CH3OH)n with n ≤ 15. The predictions are based on global optimization of three intermolecular potential energy models followed by local optimization and single-point energy calculations using two variants of dispersion-corrected density functional theory. Recurring structural motifs include folded and/or twisted rings, folded rings with a short branch, and stacked rings. Many of the larger structures are stabilized by weak C-H···O bonds.

  8. Potential energy savings and thermal comfort

    DEFF Research Database (Denmark)

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

    1996-01-01

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

  9. The first three coefficients in the high temperature series expansion of free energy for simple potential models with hard-sphere cores and continuous tails.

    Science.gov (United States)

    Zhou, Shiqi; Solana, J R

    2013-08-08

    The first three coefficients of the high temperature series expansion (HTSE) of the Helmholtz free energy for a number of simple potential models with hard-sphere cores plus continuous tails are obtained for the first time from Monte Carlo simulations. The potential models considered include Square-well, Sutherland, attractive Yukawa, and triangle-well with different potential ranges, as well as a model potential qualitatively resembling the depletion potential in colloidal dispersions. The simulation data are used to evaluate performance of a recent coupling parameter series expansion (CPSE) in calculating for these coefficients, and a traditional macroscopic compressibility approximation (MCA) for the second-order coefficient only. A comprehensive comparison based on these coefficients from the two theoretical approaches and simulations enables one to conclude that (i) unlike one common experience that the widely used MCA usually underestimates the second-order coefficient, the MCA can both overestimate and underestimate the second-order coefficient, and worsens as the range of the potential decreases; and (ii) in contrast, the CPSE not only reproduce the trends in the density dependence of the perturbation coefficients, even the third one, observed in the simulations, but also the agreement is quantitative in most cases, and this clearly highlights the potential of the CPSE in providing accurate estimations for the higher-order coefficients, thus giving rise to an accurate higher-order HTSE.

  10. The Wind Energy Potential of Iceland

    Science.gov (United States)

    Nawri, Nikolai; Nína Petersen, Guðrún; Bjornsson, Halldór; Hahmann, Andrea N.; Jónasson, Kristján; Bay Hasager, Charlotte; Clausen, Niels-Erik

    2014-05-01

    While Iceland has an abundant wind energy resource, its use for electrical power production has so far been limited. Electricity in Iceland is generated primarily from hydro- and geothermal sources, and adding wind energy has so far not been considered practical or even necessary. However, wind energy is becoming a more viable option, as opportunities for new hydro- or geothermal power installations become limited. In order to obtain an estimate of the wind energy potential of Iceland, a wind atlas has been developed as part of the joint Nordic project 'Improved Forecast of Wind, Waves and Icing' (IceWind). Downscaling simulations performed with the Weather Research and Forecasting (WRF) model were used to determine the large-scale wind energy potential of Iceland. Local wind speed distributions are represented by Weibull statistics. The shape parameter across Iceland varies between 1.2 and 3.6, with the lowest values indicative of near-exponential distributions at sheltered locations, and the highest values indicative of normal distributions at exposed locations in winter. Compared with summer, average power density in winter is increased throughout Iceland by a factor of 2.0 - 5.5. In any season, there are also considerable spatial differences in average wind power density. Relative to the average value within 10 km of the coast, power density across Iceland varies between 50 - 250%, excluding glaciers, or between 300 - 1500 W m-2 at 50 m above ground level in winter. At intermediate elevations of 500 - 1000 m above mean sea level, power density is independent of the distance to the coast. In addition to seasonal and spatial variability, differences in average wind speed and power density also exist for different wind directions. Along the coast in winter, power density of onshore winds is higher by 100 - 700 W m-2 than that of offshore winds. The regions with the highest average wind speeds are impractical for wind farms, due to the distances from road

  11. Assessing the urban solar energy resource potential of Davao City, Philippines, using LiDAR Digital Surface Model (DSM) and GRASS GIS

    Science.gov (United States)

    Teves, Justine; Sola, Eula Fae; Pintor, Ben Hur; Ang, Ma. Rosario Concepcion

    2016-10-01

    Solar energy is emerging as one of the top options for renewable energy sources in the Philippines, with largescale solar photovoltaic (PV) farms being built all over the country. Solar energy resource in the urban environment has great potential in making a city self-sustaining, but has not been fully explored for the country. In order to represent its potential, reliable resource assessment should be done. This study aims to assess the available solar energy resource in Davao City, a trade and commerce hub in southern Philippines. The functions of GRASS GIS, specifically the r.sun module, in modelling incoming solar radiation is discussed, along with the use of a one-meter LiDAR Digital Surface Model (DSM) and Linke Turbidity coefficients as inputs. The average Julian day of each month was used to compute the Global Horizontal Irradiation (GHI) values under clear-sky or cloudless conditions. To account for the effects of the clouds in the study area, the clear-sky indices (Kc) were computed using data from solar recording stations of the Bureau of Soils and Water Management (BSWM) found within and around the region. These were multiplied to the modelled clear-sky GHI rasters to get the real-sky GHI. The results show that the city's average GHI potential ranges from 2693.79 Wh/m2 and 4453.13 Wh/m2. Average values are particularly higher around the months of March and April, while lower values are seen in the months of November and January. Areas with higher potential are seen in the southern portion of the city, consistent in built-up areas.

  12. Per-residue energy decomposition pharmacophore model to enhance virtual screening in drug discovery: a study for identification of reverse transcriptase inhibitors as potential anti-HIV agents.

    Science.gov (United States)

    Cele, Favourite N; Ramesh, Muthusamy; Soliman, Mahmoud Es

    2016-01-01

    A novel virtual screening approach is implemented herein, which is a further improvement of our previously published "target-bound pharmacophore modeling approach". The generated pharmacophore library is based only on highly contributing amino acid residues, instead of arbitrary pharmacophores, which are most commonly used in the conventional approaches in literature. Highly contributing amino acid residues were distinguished based on free binding energy contributions obtained from calculation from molecular dynamic (MD) simulations. To the best of our knowledge; this is the first attempt in the literature using such an approach; previous approaches have relied on the docking score to generate energy-based pharmacophore models. However, docking scores are reportedly unreliable. Thus, we present a model for a per-residue energy decomposition, constructed from MD simulation ensembles generating a more trustworthy pharmacophore model, which can be applied in drug discovery workflow. This work is aimed at introducing a more rational approach to the field of drug design, rather than comparing the validity of this approach against those previously reported. We recommend additional computational and experimental work to further validate this approach. This approach was used to screen for potential reverse transcriptase inhibitors using the pharmacophoric features of compound GSK952. The complex was subjected to docking, thereafter, MD simulation confirmed the stability of the system. Experimentally determined inhibitors with known HIV-reverse transcriptase inhibitory activity were used to validate the protocol. Two potential hits (ZINC46849657 and ZINC54359621) showed a significant potential with regard to free binding energy. Reported results obtained from this work confirm that this new approach is favorable in the future of the drug design industry.

  13. Collisions of halogen (/sup 2/P) and rare gas (/sup 1/S) atoms. [Differential cross sections, elastic model, coupling potential energy, L-S coupling, multiplets

    Energy Technology Data Exchange (ETDEWEB)

    Becker, C.H.

    1978-12-01

    Differential cross sections I (THETA) at several collision energies measured in crossed molecular beam experiments are reported for several combinations of halogen atoms (/sup 2/P) scattered off rare gas-rare gas atoms (/sup 1/S/sub 0/), namely, F + Ne, F + Ar, F + Kr, F + Xe, C1 + Xe. The scattering is described by an elastic model appropriate to Hund's case c coupling. With the use of this model, the X 1/2, I 3/2, and II 1/2 interaction potential energy curves are derived by fitting calculated differential cross sections, based on analytic representations of the potentials, to the data. The F - Xe X 1/2 potential shows a significant bonding qualitatively different than for the other F-rare gases. The I 3/2 and II 1/2 potentials closely resemble the van der Waals interactions of the one electron richer ground state rare gas-rare gas systems. Coupled-channel scattering calculations are carried out for F + Ar, F + Xe, and C1 + Xe using the realistic potential curves derived earlier. The results justify the use of the elastic model, and give additional information on intramultiplet and intermultiplet transitions. The transitions are found to be governed by the crossing of the two ..cap omega.. = 1/2 potentials in the complex plane. The measured I (theta) and I (THETA) derived from the coupled-channel computations show small oscillations or perturbations (Stueckelberg oscillations) though quantitative agreement is not obtained.The nature of the anomalous F - Xe X 1/2 potential is discussed as is the approximation of a constant spin orbit coupling over the experimentally accessible range of internuclear distances for these open shell molecules. 55 references.

  14. Historical Perspective on How and Why Switchgrass was Selected as a "Model" High-Potential Energy Crop

    Energy Technology Data Exchange (ETDEWEB)

    Wright, Lynn L [ORNL

    2007-11-01

    A review of several publications of the Biofuels Feedstock Development Program, and final reports from the herbaceous crop screening trials suggests that there were several technical and non-technical factors that influenced the decision to focus on one herbaceous "model" crop species. The screening trials funded by the U.S. Department of Energy in the late 1980's to early 1990's assessed a wide range of about 34 species with trials being conducted on a wide range of soil types in 31 different sites spread over seven states in crop producing regions of the U.S. While several species, including sorghums, reed canarygrass and other crops, were identified as having merit for further development, the majority of institutions involved in the herbaceous species screening studies identified switchgrass as having high priority for further development. Six of the seven institutions included switchgrass among the species recommended for further development in their region and all institutions recommended that perennial grasses be given high research priority. Reasons for the selection of switchgrass included the demonstration of relatively high, reliable productivity across a wide geographical range, suitability for marginal quality land, low water and nutrient requirements, and positive environmental attributes. Economic and environmental assessments by Oak Ridge National Laboratory's Biofuels Feedstock Development Program staff together with the screening project results, and funding limitations lead to making the decision to further develop only switchgrass as a "model" or "prototype" species in about 1990. This paper describes the conditions under which the herbaceous species were screened, summarizes results from those trials, discusses the various factors which influenced the selection of switchgrass, and provides a brief evaluation of switchgrass with respect to criteria that should be considered when selecting and developing a crop for biofuels and

  15. Storing unsteady energy, like photovoltaically generated electric energy, as potential energy

    OpenAIRE

    Kutz, Nadja

    2012-01-01

    A proposal to store unsteady energy in potential energy via lifting masses with a rough quantitative overview. Some applications and methods to harvest the potential energy are also given. A focus is put on photovoltaically generated energy.

  16. The isovector/isoscalar ratio for the imaginary part of the medium-energy nucleon optical model potential studied by the quantum molecular dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Chiba, Satoshi; Niita, Koji; Fukahori, Tokio; Maruyama, Tomoyuki; Maruyama, Toshiki; Iwamoto, Akira [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1997-05-01

    Energy dependence of the ratio of the isovector and isoscalar strengths in the imaginary part of the nucleon optical model potential at the medium energy range was extracted from an analysis of proton and neutron induced total reaction cross sections on {sup 11}Li with a theoretical framework called quantum molecular dynamics (QMD). The isovector/isoscalar ratio was found to be about 0.8 at 100 MeV, and decreased almost linearly in log(E) to 0 at several hundred MeV. This result was consistent with an estimate at lower energy, and was also in good accord with the values used by Kozack and Madland for the analysis of nucleon + {sup 208}Pb reactions. (author)

  17. Geothermal Energy Potential in Western United States

    Science.gov (United States)

    Pryde, Philip R.

    1977-01-01

    Reviews types of geothermal energy sources in the western states, including hot brine systems and dry steam systems. Conversion to electrical energy is a major potential use of geothermal energy, although it creates environmental disruptions such as noise, corrosion, and scaling of equipment. (AV)

  18. Geothermal Energy Potential in Western United States

    Science.gov (United States)

    Pryde, Philip R.

    1977-01-01

    Reviews types of geothermal energy sources in the western states, including hot brine systems and dry steam systems. Conversion to electrical energy is a major potential use of geothermal energy, although it creates environmental disruptions such as noise, corrosion, and scaling of equipment. (AV)

  19. Energy potential mapping for energy-producing neighborhoods

    NARCIS (Netherlands)

    Dobbelsteen, van den A.; Broersma, S.; Stremke, S.

    2011-01-01

    Over the past five years, the method of energy potential mapping (EPM) has evolved from a cartoonish charting of climatic features with energy consequences to a detailed methodology for the development of spatial plans based on energy-effective foundations. By means of EPM the rudimentary features

  20. IRETHERM: Developing a Strategic and Holistic Understanding of Ireland's Geothermal Energy Potential through Integrated Modelling of New and Existing Geophysical, Geochemical and Geological Data

    Science.gov (United States)

    Jones, Alan G.; Daly, Stephen; Vozar, Jan; Rath, Volker; Campanya, Joan; Blake, Sarah; Delhaye, Robert; Fritschle, Tobias; Willmot Noller, Nicola; Long, Mike; Waters, Tim

    2015-04-01

    The Science Foundation Ireland funded academia-government-industry collaborative IRETHERM project (www.iretherm.ie), initiated in 2011, is developing a strategic understanding of Ireland's (all-island) deep geothermal energy potential through integrated modelling of new and existing geophysical, geochemical and geological data. Potential applications include both low enthalpy district space heating of large urban centres and electricity generation from intermediate-temperature waters. IRETHERM comprises three broad geothermal target types; 1) Assessment of the geothermal energy potential of Ireland's radiogenic granites (EGS), (2) Assessment of the geothermal energy potential of Ireland's deep sedimentary basins (HSA), and, (3) Assessment of the geothermal energy potential of warm springs. The geophysical subsurface imaging techniques of choice are controlled-source (CSEM) and natural-source (magnetotellurics, MT) electromagnetic methods. Electrical conductivity, being a transport property, is a proxy for permeability, and appropriate porosity-permeability relations are being developed. To date, MT measurements have been made at 466 sites over sedimentary basins (190 sites), granites (156 sites) and warm springs (120 sites), with CSEM across one warm spring. An ongoing continuous geochemical (temperature and electrical conductivity every 15 mins) and time-lapse seasonal hydrochemical sampling programmes are in progress at six warm spring sites. A database on heat production in Irish rocks has been compiled, of more than 3,300 geochemical sample measurements, with 3,000 retrieved from various archives and over 300 new analyses. Geochemistry, geochronology and isotopic analyses have been conducted on subsurface granites and exposed analogues astride the Iapetus Suture Zone in order to understand the underlying reasons for their radiogenic heat production. Finally, thermal conductivity measurements have been made on borehole samples from representative lithologies

  1. Energy Savings Potential and Research & Development Opportunities for Commercial Refrigeration

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2009-09-01

    This study documents the energy consumption of commercial refrigeration equipment (CRE) in the U.S. and evaluated the energy savings potential of various technologies and energy efficiency measures that could be applied to such equipment. The study provided an overview of CRE applications, assessed the energy-savings potential of CRE in the U.S., outline key barriers to adoption of energy-savings technologies, and recommended opportunities for advanced energy saving technology research. The study was modeled after an earlier 1996 report by Arthur D. Little, Inc., and updated key information, examined more equipment types, and outlined long-term research and development opportunities.

  2. Renewable energy costs, potentials, barriers. Conceptual issues

    Energy Technology Data Exchange (ETDEWEB)

    Verbruggen, Aviel [University of Antwerp (Belgium); Fischedick, Manfred [Wuppertal Institute for Climate, Environment, Energy (Germany); Moomaw, William [Tufts University, Center for International Environment and Resource Policy (United States); Weir, Tony [University of the South Pacific, Fiji Islands (Fiji); Nadai, Alain [Centre International de Recherche sur Environnement et le Developpement CIRED (France); Nilsson, Lars J. [University of Lund (Sweden); Nyboer, John [Simon Fraser University, School of Resource and Environmental Management (Canada); Sathaye, Jayant [Lawrence Berkeley Laboratory (United States)

    2010-02-15

    Renewable energy can become the major energy supply option in low-carbon energy economies. Disruptive transformations in all energy systems are necessary for tapping widely available renewable energy resources. Organizing the energy transition from non-sustainable to renewable energy is often described as the major challenge of the first half of the 21st century. Technological innovation, the economy (costs and prices) and policies have to be aligned to achieve full renewable energy potentials, and barriers impeding that growth need to be removed. These issues are also covered by IPCC's special report on renewable energy and climate change to be completed in 2010. This article focuses on the interrelations among the drivers. It clarifies definitions of costs and prices, and of barriers. After reviewing how the third and fourth assessment reports of IPCC cover mitigation potentials and commenting on definitions of renewable energy potentials in the literature, we propose a consistent set of potentials of renewable energy supplies. (author)

  3. Model-based assessment of the potential of seasonal aquifer thermal energy storage and recovery as a groundwater ecosystem service for the Brussels-Capital Region

    Science.gov (United States)

    Anibas, Christian; Huysmans, Marijke

    2015-04-01

    transport models on several pilot sites within this region, our study aims to better quantify the potential for ATES systems in these aquifers. Covering several dozen square kilometres, the models investigate interaction processes between ATES installations and other competing groundwater usages, including groundwater abstraction. Based on the model results ecological and economical balance calculations should better define the effects of ATES systems. Aimed at experts and decision makers this research project delivers a detailed foundation for the exploitation of seasonal aquifer thermal storage in the aquifers of the Brussels-Capital Region as an ecosystem service, and should assist in establishing guidelines for planning, building and maintaining high performing ATES systems. References BONTE, M., STUYFZAND, P.J., HULSMANN, A., VAN BEELEN, P. (2011): Underground thermal energy storage: environmental risks and policy developments in the Netherlands and European Union. Ecology and Society 16 (1): 22. VITO, (2007): Studie van de geothermische en hydrothermische technieken die toepasbaar zijn in Brussel: wettelijke context, milieu-impact, goede praktijk en economisch potentieel (in Dutch); Mol, Belgium. ZUURBIER, K.G., HARTOG, N., VALSTAR, J., POST, V.E., VAN BREUKELEN, B.M., (2013): The impact of low temperature seasonal aquifer thermal energy storage (SATES) systems on chlorinated solvent contaminated groundwater: modeling of spreading and degradation. Journal of Contaminant Hydrology 147: 1-13.

  4. Quark confinement potential examined by excitation energy of the Lambda_c and Lambda_b baryons in a quark-diquark model

    CERN Document Server

    Jido, Daisuke

    2016-01-01

    The possibility to have diquark configuration in heavy baryons, such as Lambda_c and Lambda_b, is examined by a nonrelativistic potential model with a heavy quark and a light scalar diquark. Assuming that the Lambda_c and Lambda_b baryons are composed of the heavy quark and the scalar-isoscalar ud diquark, we solve the two-body Schrodinger equation with the Coulomb plus linear potential and obtain the energy spectra for the heavy baryons. Contrary to our expectation, it is found that the potential determined by the quarkonium spectra fails to reproduce the excitation spectra of the Lambda_c and Lambda_b in the quark-diquark picture, while the Lambda_c and Lambda_b spectra is reproduced with a half strength of the confinement string tension than for the quarkonium. The Xi_c excitation energy is also calculated and is found to be smaller than Lambda_c in the quark-diquark model. This is not consistent with the experimental observation. These puzzles should be solved when one takes the quark-diquark picture for ...

  5. Quark confinement potential examined by excitation energy of the Λc and Λb baryons in a quark-diquark model

    Science.gov (United States)

    Jido, Daisuke; Sakashita, Minori

    2016-08-01

    The possibility of having a diquark configuration in heavy baryons, such as Λ and Λ, is examined by a nonrelativistic potential model with a heavy quark and a light scalar diquark. Assuming that the Λ and Λ baryons are composed of the heavy quark and the point-like scalar-isoscalar ud diquark, we solve the two-body Schrödinger equation with the Coulomb plus linear potential and obtain the energy spectra for the heavy baryons. Contrary to our expectation, it is found that the potential determined by the quarkonium spectra fails to reproduce the excitation spectra of the Λ and Λ in the quark-diquark picture, while the Λ and Λ spectra are reproduced with half the strength of the confinement string tension than for the quarkonium. The finite size effect of the diquark is also examined and it is found that the introduction of a finite size diquark would resolve the failure of the spectrum reproduction. The Ξ excitation energy is also calculated and is found to be smaller than Λ in the quark-diquark model. This is not consistent with experimental observations.

  6. Multi-dimensional potential energy surfaces and non-axial octupole correlations in actinide and transfermium nuclei from relativistic mean field models

    CERN Document Server

    Lu, Bing-Nan; Zhao, En-Guang; Zhou, Shan-Gui

    2013-01-01

    We have developed multi-dimensional constrained covariant density functional theories (MDC-CDFT) for finite nuclei in which the shape degrees of freedom \\beta_{\\lambda\\mu} with even \\mu, e.g., \\beta_{20}, \\beta_{22}, \\beta_{30}, \\beta_{32}, \\beta_{40}, etc., can be described simultaneously. The functional can be one of the following four forms: the meson exchange or point-coupling nucleon interactions combined with the non-linear or density-dependent couplings. For the pp channel, either the BCS approach or the Bogoliubov transformation is implemented. The MDC-CDFTs with the BCS approach for the pairing (in the following labelled as MDC-RMF models with RMF standing for "relativistic mean field") have been applied to investigate multi-dimensional potential energy surfaces and the non-axial octupole $Y_{32}$-correlations in N=150 isotones. In this contribution we present briefly the formalism of MDC-RMF models and some results from these models. The potential energy surfaces with and without triaxial deformatio...

  7. Zeta-function approach to Casimir energy with singular potentials

    CERN Document Server

    Khusnutdinov, N R

    2006-01-01

    In the framework of zeta-function approach the Casimir energy for three simple model system: single delta potential, step function potential and three delta potentials is analyzed. It is shown that the energy contains contributions which are peculiar to the potentials. It is suggested to renormalize the energy using the condition that the energy of infinitely separated potentials is zero which corresponds to subtraction all terms of asymptotic expansion of zeta-function. The energy obtained in this way obeys all physically reasonable conditions. It is finite in the Dirichlet limit and it may be attractive or repulsive depending on the strength of potential. The effective action is calculated and it is shown that the surface contribution appears. The renormalization of the effective action is discussed.

  8. The Wind Energy Potential of Iceland

    DEFF Research Database (Denmark)

    Nawri, Nikolai; Petersen, Guðrún Nína; Björnsson, Halldór

    2014-01-01

    Downscaling simulations performed with theWeather Research and Forecasting (WRF) model were used to determine the large-scale wind energy potential of Iceland. Local wind speed distributions are represented by Weibull statistics. The shape parameter across Iceland varies between 1.2 and 3.......6, with the lowest values indicative of near-exponential distributions at sheltered locations, and the highest values indicative of normal distributions at exposed locations in winter. Compared with summer, average power density in winter is increased throughout Iceland by a factor of 2.0e5.5. In any season......, there are also considerable spatial differences in average wind power density. Relative to the average value within 10 km of the coast, power density across Iceland varies between 50 and 250%, excluding glaciers, or between 300 and 1500 W m_2 at 50 m above ground level in winter. At intermediate elevations...

  9. Wind energy in China: Estimating the potential

    Science.gov (United States)

    Yuan, Jiahai

    2016-07-01

    Persistent and significant curtailment has cast concern over the prospects of wind power in China. A comprehensive assessment of the production of energy from wind has identified grid-integrated wind generation potential at 11.9-14% of China's projected energy demand by 2030.

  10. National Energy Modeling System

    Energy Technology Data Exchange (ETDEWEB)

    Skinner, C.W. (Energy Information Administration, Washington, DC (United States))

    1993-01-01

    The Energy Information Administration is developing a new National Energy Modeling System to provide annual forecasts of energy supply, demand, and prices on a regional basis in the United States and, to a limited extent, in the rest of the world. The design for the system was based on a requirements analysis, a comparison of requirements with existing modeling capabilities, and a series of widely circulated issue papers defining the choices and tradeoffs for 13 key design decisions. An initial prototpye of the new NEMS was implemented in late 1992, with a more complete, operational version in 1993. NEMS is expected to provide EIA and other users with a greatly enhanced ability to illustrate quickly and effectively the effects of a wide range of energy policy proposals.

  11. 100% DD Energy Model Update

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2011-06-30

    The Miami Science Museum energy model has been used during DD to test the building's potential for energy savings as measured by ASHRAE 90.1-2007 Appendix G. This standard compares the designed building's yearly energy cost with that of a code-compliant building. The building is currently on track show 20% or better improvement over the ASHRAE 90.1-2007 Appendix G baseline; this performance would ensure minimum compliance with both LEED 2.2 and current Florida Energy Code, which both reference a less strict version of ASHRAE 90.1. In addition to being an exercise in energy code compliance, the energy model has been used as a design tool to show the relative performance benefit of individual energy conservation measures (ECMs). These ECMs are areas where the design team has improved upon code-minimum design paths to improve the energy performance of the building. By adding ECMs one a time to a code-compliant baseline building, the current analysis identifies which ECMs are most effective in helping the building meet its energy performance goals.

  12. Studies of breakeven prices and electricity supply potentials of nuclear fusion by a long-term world energy and environment model

    Science.gov (United States)

    Tokimatsu, K.; Asaoka, Y.; Konishi, S.; Fujino, J.; Ogawa, Y.; Okano, K.; Nishio, S.; Yoshida, T.; Hiwatari, R.; Yamaji, K.

    2002-11-01

    In response to social demand, this paper investigates the breakeven price (BP) and potential electricity supply of nuclear fusion energy in the 21st century by means of a world energy and environment model. We set the following objectives in this paper: (i) to reveal the economics of the introduction conditions of nuclear fusion; (ii) to know when tokamak-type nuclear fusion reactors are expected to be introduced cost-effectively into future energy systems; (iii) to estimate the share in 2100 of electricity produced by the presently designed reactors that could be economically selected in the year. The model can give in detail the energy and environment technologies and price-induced energy saving, and can illustrate optimal energy supply structures by minimizing the costs of total discounted energy systems at a discount rate of 5%. The following parameters of nuclear fusion were considered: cost of electricity (COE) in the nuclear fusion introduction year, annual COE reduction rates, regional introduction year, and regional nuclear fusion capacity projection. The investigations are carried out for three nuclear fusion projections one of which includes tritium breeding constraints, four future CO2 concentration constraints, and technological assumptions on fossil fuels, nuclear fission, CO2 sequestration, and anonymous innovative technologies. It is concluded that: (1) the BPs are from 65 to 125 mill kW-1 h-1 depending on the introduction year of nuclear fusion under the 550 ppmv CO2 concentration constraints; those of a business-as-usual (BAU) case are from 51 to 68 mill kW-1h-1. Uncertainties resulting from the CO2 concentration constraints and the technological options influenced the BPs by plus/minus some 10 30 mill kW-1h-1, (2) tokamak-type nuclear fusion reactors (as presently designed, with a COE range around 70 130 mill kW-1h-1) would be favourably introduced into energy systems after 2060 based on the economic criteria under the 450 and 550 ppmv CO2

  13. Timing of potential and metabolic brain energy

    DEFF Research Database (Denmark)

    Korf, Jakob; Gramsbergen, Jan Bert

    2007-01-01

    The temporal relationship between cerebral electro-physiological activities, higher brain functions and brain energy metabolism is reviewed. The duration of action potentials and transmission through glutamate and GABA are most often less than 5 ms. Subjects may perform complex psycho-physiologic......The temporal relationship between cerebral electro-physiological activities, higher brain functions and brain energy metabolism is reviewed. The duration of action potentials and transmission through glutamate and GABA are most often less than 5 ms. Subjects may perform complex psycho...... functions. We introduce the concepts of potential and metabolic brain energy to distinguish trans-membrane gradients of ions or neurotransmitters and the capacity to generate energy from intra- or extra-cerebral substrates, respectively. Higher brain functions, such as memory retrieval, speaking...

  14. Geothermal Energy: Delivering on the Global Potential

    Directory of Open Access Journals (Sweden)

    Paul L. Younger

    2015-10-01

    Full Text Available Geothermal energy has been harnessed for recreational uses for millennia, but only for electricity generation for a little over a century. Although geothermal is unique amongst renewables for its baseload and renewable heat provision capabilities, uptake continues to lag far behind that of solar and wind. This is mainly attributable to (i uncertainties over resource availability in poorly-explored reservoirs and (ii the concentration of full-lifetime costs into early-stage capital expenditure (capex. Recent advances in reservoir characterization techniques are beginning to narrow the bounds of exploration uncertainty, both by improving estimates of reservoir geometry and properties, and by providing pre-drilling estimates of temperature at depth. Advances in drilling technologies and management have potential to significantly lower initial capex, while operating expenditure is being further reduced by more effective reservoir management—supported by robust models—and increasingly efficient energy conversion systems (flash, binary and combined-heat-and-power. Advances in characterization and modelling are also improving management of shallow low-enthalpy resources that can only be exploited using heat-pump technology. Taken together with increased public appreciation of the benefits of geothermal, the technology is finally ready to take its place as a mainstream renewable technology, exploited far beyond its traditional confines in the world’s volcanic regions.

  15. Bohm's Quantum Potential as an Internal Energy

    OpenAIRE

    Dennis, Glen; De Gosson, Maurice,; Hiley, Basil

    2014-01-01

    We pursue our discussion of Fermi's surface initiated in Dennis, de Gosson and Hiley and show that Bohm's quantum potential can be viewed as an internal energy of a quantum system. This gives further insight into the role it played by the quantum potential in stationary states. It also allows us to provide a physically motivated derivation of Schr\\"odinger's equation for a particle in an external potential.

  16. On the hypothetical utilization of atmospheric potential energy

    Directory of Open Access Journals (Sweden)

    Thomas Frisius

    2014-09-01

    Full Text Available Atmospheric potential energy is typically divided into an available and a nonavailable part. In this article a hypothetical utilization of a fraction of the nonavailable potential energy is described. This part stems from the water vapor that can be converted into the liquid phase. An energy gain results when the potential energy of the condensate relative to a reference height exceeds the energy necessary to condensate the water vapor. It is shown that this can be the case in a saturated atmosphere without convective available potential energy. Finally, simulations with the numerical cloud model HURMOD are performed to estimate the usability of the device in practice. Indeed, a positive energy output results in a simulation with immediate gathering of the condensate. On the contrary, potential energy gained falls significantly short of the necessary energy for forming the condensate when a realistic cloud microphysical scheme allowing re-evaporation of condensate is applied. Taken together it can be concluded that, a utilization of atmospheric potential energy is hypothetically possible but the practical realization is probably not feasible.

  17. He-, Ne-, and Ar-phosgene intermolecular potential energy surfaces

    DEFF Research Database (Denmark)

    Munteanu, Cristian R.; Henriksen, Christian; Felker, Peter M.

    2013-01-01

    Using the CCSD(T) model, we evaluated the intermolecular potential energy surfaces of the He-, Ne-, and Ar-phosgene complexes. We considered a representative number of intermolecular geometries for which we calculated the corresponding interaction energies with the augmented (He complex) and double...

  18. Alternative energies: Engineering, economics, market potential

    Energy Technology Data Exchange (ETDEWEB)

    Hake, B.

    1981-11-01

    Rentability calculations are disappointing for most alternative energies. Technical improvements that might change this are not in sight, so that the dependence on imported oil and gas will hardly be reduced. Producers of solar collectors, heat pumps, solar cells, and cogeneration units must keep in mind that the market will hardly expand. This was the result of a seminar on 'Alternative energy sources: Technology, economics, marketing potential - a critical review', held on May 5 at Haus der Technik, Essen.

  19. NVU dynamics. III. Simulating molecules at constant potential energy

    DEFF Research Database (Denmark)

    Ingebrigtsen, Trond; Dyre, J. C.

    2012-01-01

    This is the final paper in a series that introduces geodesic molecular dynamics at constant potential energy. This dynamics is entitled NVU dynamics in analogy to standard energy-conserving Newtonian NVE dynamics. In the first two papers [T. S. Ingebrigtsen, S. Toxvaerd, O. J. Heilmann, T. B....... In this paper, the NVU algorithm for atomic systems is extended to be able to simulate the geodesic motion of molecules at constant potential energy. We derive an algorithm for simulating rigid bonds and test this algorithm on three different systems: an asymmetric dumbbell model, Lewis-Wahnström o......-terphenyl (OTP) and rigid SPC/E water. The rigid bonds introduce additional constraints beyond that of constant potential energy for atomic systems. The rigid-bond NVU algorithm conserves potential energy, bond lengths, and step length for indefinitely long runs. The quantities probed in simulations give results...

  20. Production systems and energy potential of tidal energy

    Directory of Open Access Journals (Sweden)

    Julián Rodrigo Quintero-González

    2016-01-01

    Full Text Available This article discusses the concept of tidal power and distinguishes the types of systems to exploitation the tidal energy; the same way; it also shows how this technology serves as a source of energy in some countries around the world, which is a role associated with the energy potential available in each region. This point equally shows through numbers in GWh/year per km2 reservoir surface. Last but not least, it is the influence that this technology has had on the environment, its contributions for improving and evaluating from an environmental point of view.

  1. Global investigation of potential energy surfaces for the pyrolysis of C(1)-C(3) hydrocarbons: toward the development of detailed kinetic models from first principles.

    Science.gov (United States)

    Ryazantsev, Mikhail N; Jamal, Adeel; Maeda, Satoshi; Morokuma, Keiji

    2015-11-07

    Detailed kinetic models (DKMs) are the most fundamental "bottom-up" approaches to computational investigation of the pyrolysis and oxidation of fuels. The weakest points of existing DKMs are incomplete information about the reaction types that can be involved in the potential energy surfaces (PESs) in pyrolysis and oxidation processes. Also, the computational thermodynamic parameters available in the literature vary widely with the level of theory employed. More sophisticated models require improvement both in our knowledge of the type of the reactions involved and the consistency of thermodynamic and kinetic parameters. In this paper, we aim to address these issues by developing ab initio models that can be used to describe early stages of pyrolysis of C1-C3 hydrocarbons. We applied a recently developed global reaction route mapping (GRRM) strategy to systematically investigate the PES of the pyrolysis of C1-C3 hydrocarbons at a consistent level of theory. The reactions are classified into 14 reaction types. The critical points on the PES for all reactions in the network are calculated at the highly accurate UCCSD(T)-F12b/cc-pVTZ//UM06-2X/cc-pVTZ level of theory. The data reported in this paper can be used for first principle calculations of kinetic constants and for a subsequent study on modeling the evolution of the species from the reaction network of the pyrolysis and oxidation of C1-C3 hydrocarbons.

  2. Potential energy surface of alanine polypeptide chains

    DEFF Research Database (Denmark)

    Solov'yov, Ilia; Yakubovich, Alexander V.; Solov'yov, Andrey V.

    2006-01-01

    The multidimensional potential energy surfaces of the peptide chains consisting of three and six alanine (Ala) residues have been studied with respect to the degrees of freedom related to the twist of these molecules relative to the peptide backbone (these degrees of freedom are responsible...

  3. Solar-energy potential in Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Sozen, Adnan; Ozalp, Mehmet [Gazi Univ., Mechanical Education Dept., Ankara (Turkey); Arcaklioglu, Erol [Kirikkale Univ., Mechanical Engineering Dept., Kirikkale (Turkey); Kanit, E. Galip [Turkish State Meteorological Office, Ankara (Turkey)

    2005-04-01

    In this study, a new formula based on meteorological and geographical data was developed to determine the solar-energy potential in Turkey using artificial neural-networks (ANNs). Scaled conjugate gradient (SCG) and Levenberg-Marquardt (LM) learning algorithms and a logistic sigmoid transfer function were used in the network. Meteorological data for the last four years (2000-2003) from 18 cities (Bilecik, Kirsehir, Akhisar, Bingol, Batman, Bodrum, Uzunkopru, Sile, Bartin, Yalova, Horasan, Polatli, Malazgirt, Koycegiz, Manavgat, Dortyol, Karatas and Birecik) spread over Turkey were used as data in order to train the neural network. Meteorological and geographical data (latitude, longitude, altitude, month, mean sunshine duration, and mean temperature) were used in the input layer of the network. Solar radiation is the output layer. One-month test data for each city was used, and these months data were not used for training. The results show that the maximum mean absolute percentage error (MAPE) was found to be 3.448% and the R{sup 2} value 0.9987 for Polatli. The best approach was found for Kirsehir (MAPE=1.2257, R{sup 2}=0.9998). The MAPE and R{sup 2} for the testing data were 3.3477 and 0.998534, respectively. The ANN models show greater accuracy for evaluating solar-resource possibilities in regions where a network of monitoring stations has not been established in Turkey. This study confirms the ability of the ANN to predict solar-radiation values precisely (Author)

  4. Solar-energy potential in Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Soezen, Adnan; Arcaklioglu, Erol; Oezalp, Mehmet; Kanit, E. Galip

    2005-04-01

    In this study, a new formula based on meteorological and geographical data was developed to determine the solar-energy potential in Turkey using artificial neural-networks (ANNs). Scaled conjugate gradient (SCG) and Levenberg-Marquardt (LM) learning algorithms and a logistic sigmoid transfer function were used in the network. Meteorological data for the last four years (2000 {yields} 2003) from 18 cities (Bilecik, Kirsehir, Akhisar, Bingoel, Batman, Bodrum, Uzunkoeprue, Sile, Bartin, Yalova, Horasan, Polatli, Malazgirt, Koeycegiz, Manavgat, Doertyol, Karatas and Birecik) spread over Turkey were used as data in order to train the neural network. Meteorological and geographical data (latitude, longitude, altitude, month, mean sunshine duration, and mean temperature) were used in the input layer of the network. Solar radiation is the output layer. One-month test data for each city was used, and these months data were not used for training. The results show that the maximum mean absolute percentage error (MAPE) was found to be 3.448% and the R{sup 2} value 0.9987 for Polatli. The best approach was found for Kirsehir (MAPE=1.2257, R{sup 2}=0.9998). The MAPE and R{sup 2} for the testing data were 3.3477 and 0.998534, respectively. The ANN models show greater accuracy for evaluating solar-resource possibilities in regions where a network of monitoring stations has not been established in Turkey. This study confirms the ability of the ANN to predict solar-radiation values precisely.

  5. Scenarios of energy demand and efficiency potential for Bulgaria

    Energy Technology Data Exchange (ETDEWEB)

    Tzvetanov, P.; Ruicheva, M.; Denisiev, M.

    1996-12-31

    The paper presents aggregated results on macroeconomic and final energy demand scenarios developed within the Bulgarian Country Study on Greenhouse Gas Emissions Mitigation, supported by US Country Studies Program. The studies in this area cover 5 main stages: (1) {open_quotes}Baseline{close_quotes} and {open_quotes}Energy Efficiency{close_quotes} socioeconomic and energy policy philosophy; (2) Modeling of macroeconomic and sectoral development till 2020; (3) Expert assessments on the technological options for energy efficiency increase and GHG mitigation in the Production, Transport and Households and Services Sectors; (4) Bottom-up modeling of final energy demand; and (5) Sectoral and overall energy efficiency potential and policy. Within the Bulgarian Country Study, the presented results have served as a basis for the final integration stage {open_quotes}Assessment of the Mitigation Policy and Measures in the Energy System of Bulgaria{close_quotes}.

  6. Potential Energy Cost Savings from Increased Commercial Energy Code Compliance

    Energy Technology Data Exchange (ETDEWEB)

    Rosenberg, Michael I.; Hart, Philip R.; Athalye, Rahul A.; Zhang, Jian; Cohan, David F.

    2016-08-22

    An important question for commercial energy code compliance is: “How much energy cost savings can better compliance achieve?” This question is in sharp contrast to prior efforts that used a checklist of code requirements, each of which was graded pass or fail. Percent compliance for any given building was simply the percent of individual requirements that passed. A field investigation method is being developed that goes beyond the binary approach to determine how much energy cost savings is not realized. Prototype building simulations were used to estimate the energy cost impact of varying levels of non-compliance for newly constructed office buildings in climate zone 4C. Field data collected from actual buildings on specific conditions relative to code requirements was then applied to the simulation results to find the potential lost energy savings for a single building or for a sample of buildings. This new methodology was tested on nine office buildings in climate zone 4C. The amount of additional energy cost savings they could have achieved had they complied fully with the 2012 International Energy Conservation Code is determined. This paper will present the results of the test, lessons learned, describe follow-on research that is needed to verify that the methodology is both accurate and practical, and discuss the benefits that might accrue if the method were widely adopted.

  7. Divacancy binding energy, formation energy and surface energy of BCC transition metals using MEAM potentials

    Science.gov (United States)

    Uniyal, Shweta; Chand, Manesh; Joshi, Subodh; Semalty, P. D.

    2016-05-01

    The modified embedded atom method (MEAM) potential parameters have been employed to calculate the unrelaxed divacancy formation energy, binding energy and surface energies for low index planes in bcc transition metals. The calculated results of divacancy binding energy and vacancy formation energy compare well with experimental and other available calculated results.

  8. An assessement of global energy resource economic potentials

    CERN Document Server

    Mercure, J F

    2012-01-01

    This paper presents an assessment of global economic energy potentials for all major natural energy resources. This work is based on both an extensive literature review and calculations using natural resource assessment data. Economic potentials are presented in the form of cost-supply curves, in terms of energy flows for renewable energy sources, or fixed amounts for fossil and nuclear resources, with strong emphasis on uncertainty, using a consistent methodology that allow direct comparisons to be made. In order to interpolate through available resource assessment data and associated uncertainty, a theoretical framework and a computational methodology are given based on statistical properties of different types of resources, justified empirically by the data, and used throughout. This work aims to provide a global database for natural energy resources ready to integrate into models of energy systems, enabling to introduce at the same time uncertainty over natural resource assessments. The supplementary mate...

  9. On the wave energy potential of Western Black Sea shelf

    CERN Document Server

    Galabov, Vasko

    2013-01-01

    In the present study we evaluate the approaches to estimate the wave energy potential of the western Black Sea shelf with numerical models. For the purpose of our evaluation and due to the lack of long time series of measurements in the selected area of the Black Sea, we compare the modeled mean wave power flux output from the SWAN wave model with the only available long term measurements from the buoy of Gelendzhik for the period 1997-2003 (with gaps). The forcing meteorological data for the numerical wave models for the selected years is extracted from the ERA Interim reanalysis of ECMWF (European Centre for Medium range Forecasts). For the year 2003 we also compare the estimated wave power with the modeled by SWAN, using ALADIN regional atmospheric model winds. We try to identify the shortcomings and limitations of the numerical modeling approach to the evaluation of the wave energy potential in Black Sea.

  10. EU project 'ThermoMap'. Model for assessing near-surface geothermal energy potentials; Das EU-Projekt 'ThermoMap'. Modell zur Abschaetzung oberflaechennaher Geothermiepotenziale

    Energy Technology Data Exchange (ETDEWEB)

    Bertermann, David [Erlangen-Nuernberg Univ. (Germany). GeoZentrum Nordbayern

    2011-10-15

    The EU project ''ThermoMap'' aims to evaluate the near-surface geothermal energy potential of the participating countries. The existing geoscience data sets are the fundament for this. Based on the problem and the objectives of the project, the author of the contribution under consideration explains the concept of work, presents the estimation model in a simplified form and gives an insight into the determination of the thermal conductivity and heat capacity.

  11. Energy Operation Model

    Energy Technology Data Exchange (ETDEWEB)

    2017-04-27

    Energy Operation Model (EOM) simulates the operation of the electric grid at the zonal scale, including inter-zonal transmission constraints. It generates the production cost, power generation by plant and category, fuel usage, and locational marginal price (LMP) with a flexible way to constrain the power production by environmental constraints, e.g. heat waves, drought conditions). Different from commercial software such as PROMOD IV where generator capacity and heat rate efficiency can only be adjusted on a monthly basis, EOM calculates capacity impacts and plant efficiencies based on hourly ambient conditions (air temperature and humidity) and cooling water availability for thermal plants. What is missing is a hydro power dispatch.

  12. Computed potential energy surfaces for chemical reactions

    Science.gov (United States)

    Walch, Stephen P.

    1994-01-01

    Quantum mechanical methods have been used to compute potential energy surfaces for chemical reactions. The reactions studied were among those believed to be important to the NASP and HSR programs and included the recombination of two H atoms with several different third bodies; the reactions in the thermal Zeldovich mechanism; the reactions of H atom with O2, N2, and NO; reactions involved in the thermal De-NO(x) process; and the reaction of CH(squared Pi) with N2 (leading to 'prompt NO'). These potential energy surfaces have been used to compute reaction rate constants and rates of unimolecular decomposition. An additional application was the calculation of transport properties of gases using a semiclassical approximation (and in the case of interactions involving hydrogen inclusion of quantum mechanical effects).

  13. On Euclidean designs and the potential energy

    CERN Document Server

    Miezaki, Tsuyoshi

    2011-01-01

    We study Euclidean designs from the viewpoint of the potential energy. For a finite set in Euclidean space, We formulate a linear programming bound for the potential energy by applying harmonic analysis on a sphere. We also introduce the concept of strong Euclidean designs from the viewpoint of the linear programming bound, and we give a Fisher type inequality for strong Euclidean designs. A finite set on Euclidean space is called a Euclidean a-code if any distinct two points in the set are separated at least by a. As a corollary of the linear programming bound, we give a method to determine an upper bound on the cardinalities of Euclidean a-codes on concentric spheres of given radii. Similarly we also give a method to determine a lower bound on the cardinalities of Euclidean t-designs as an analogue of the linear programming bound.

  14. Simple simulation for electron energy levels in geometrical potential wells

    CERN Document Server

    Pengpan, Teparksorn

    2008-01-01

    An octopus program is demonstrated to generate electron energy levels in three-dimensional geometrical potential wells. The wells are modeled to have shapes similar to cone, pyramid and truncated-pyramid. To simulate the electron energy levels in quantum mechanical scheme like the ones in parabolic band approximation scheme, the program is run initially to find a suitable electron mass fraction that can produce ground-state energies in the wells as close to those in quantum dots as possible and further to simulate excited-state energies. The programs also produce wavefunctions for exploring and determining their degeneracies and vibrational normal modes.

  15. Energy Savings Potential of Radiative Cooling Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, Nicholas [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wang, Weimin [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Alvine, Kyle J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Katipamula, Srinivas [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-11-30

    Pacific Northwest National Laboratory (PNNL), with funding from the U.S. Department of Energy’s (DOE’s) Building Technologies Program (BTP), conducted a study to estimate, through simulation, the potential cooling energy savings that could be achieved through novel approaches to capturing free radiative cooling in buildings, particularly photonic ‘selective emittance’ materials. This report documents the results of that study.

  16. Computing the Free Energy Barriers for Less by Sampling with a Coarse Reference Potential while Retaining Accuracy of the Target Fine Model.

    Science.gov (United States)

    Plotnikov, Nikolay V

    2014-08-12

    Proposed in this contribution is a protocol for calculating fine-physics (e.g., ab initio QM/MM) free-energy surfaces at a high level of accuracy locally (e.g., only at reactants and at the transition state for computing the activation barrier) from targeted fine-physics sampling and extensive exploratory coarse-physics sampling. The full free-energy surface is still computed but at a lower level of accuracy from coarse-physics sampling. The method is analytically derived in terms of the umbrella sampling and the free-energy perturbation methods which are combined with the thermodynamic cycle and the targeted sampling strategy of the paradynamics approach. The algorithm starts by computing low-accuracy fine-physics free-energy surfaces from the coarse-physics sampling in order to identify the reaction path and to select regions for targeted sampling. Thus, the algorithm does not rely on the coarse-physics minimum free-energy reaction path. Next, segments of high-accuracy free-energy surface are computed locally at selected regions from the targeted fine-physics sampling and are positioned relative to the coarse-physics free-energy shifts. The positioning is done by averaging the free-energy perturbations computed with multistep linear response approximation method. This method is analytically shown to provide results of the thermodynamic integration and the free-energy interpolation methods, while being extremely simple in implementation. Incorporating the metadynamics sampling to the algorithm is also briefly outlined. The application is demonstrated by calculating the B3LYP//6-31G*/MM free-energy barrier for an enzymatic reaction using a semiempirical PM6/MM reference potential. These modifications allow computing the activation free energies at a significantly reduced computational cost but at the same level of accuracy compared to computing full potential of mean force.

  17. Potential Fluctuation Equality for Free Energy Evaluation

    CERN Document Server

    Ngo, Van

    2011-01-01

    Jarzynski's equality [1] allows us to investigate free energy landscapes (FELs) by constructing distributions of work performed on a system from an initial ensemble of states to final states. This work is experimentally measured by extension-versus-force (EVF) curves. We proposed a new approach that enables us to reconstruct such FELs without necessity of measuring EVF curves. We proved that any free energy changes could be computed by measuring the fluctuations of a harmonic external potential in final states. The main assumption of our proof is that one should probably treat a potential's minimum {\\lambda} (thought to be control parameter) and time in separate and independent manners. We recovered Jarzynski's equality from the introduction of a double Heaviside function. We then applied the approach in molecular dynamics (MD) simulations to compute the free energy barrier of breaking DNA base pairs (bps). The free energy barrier for breaking a CG bp in our simulations is identified as 1.7 +/- 0.2 kcal/mol t...

  18. Exploring Geothermal Energy Potential in Ireland through 3-D Geophysical-Petrological Modelling of Surface Heat-Flow and Crustal and Upper-Mantle Structure

    Science.gov (United States)

    Fullea, J.; Muller, M. R.; Jones, A. G.

    2012-04-01

    Little is known of Ireland's deep, low-enthalpy geothermal resources and the potential for space heating and/or electricity generation based on geothermal energy to displace Ireland's significant reliance on carbon-based fuels. IRETHERM (www.iretherm.ie) is a four-and-a-half year, all-island, academic-government-industry collaborative project, initiated in 2011, with the overarching objective of developing a strategic and holistic understanding of Ireland's geothermal energy potential through integrated modelling of new and existing geophysical and geological data. One of the challenges in searching for deep geothermal resources in the relatively unexplored setting of Ireland lies in identifying those areas most likely to support significantly elevated temperatures at depth. Available borehole data, although sparse and clustered around areas of mineral and hydrocarbon interest, suggest a marked regional increase in surface heat-flow across Ireland, from ~40 mW/m2 in the south to >80 mW/m2 in the north. The origins of both the observed regional heat-flow trend and local temperature anomalies have not been investigated and are not currently understood. Although variations in the structure of the crust and lithosphere have been revealed by a number of active-source seismic and teleseismic experiments, their effects on surface heat-flow have not been modelled. Bulk 3-D variation in crustal heat-production across Ireland, which may contribute significantly to the observed regional and local temperature variations, has also not been determined. We investigate the origins of Ireland's regional heat-flow trend and regional and local temperature variations using the software package LitMod. This software combines petrological and geophysical modelling of the lithosphere and sub-lithospheric upper mantle within an internally consistent thermodynamic-geophysical framework, where all relevant properties are functions of temperature, pressure and chemical composition. The major

  19. 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.

  20. In Search of the Wind Energy Potential

    DEFF Research Database (Denmark)

    Lundtang Petersen, Erik

    2017-01-01

    The worldwide advancement of wind energy is putting high demands on a number of underlying technologies such as wind turbine aerodynamics, structural dynamics, gearbox design, electrical grid connections, and so on. As wind is the only fuel for wind power plants, naturally, wind-meteorology and w......The worldwide advancement of wind energy is putting high demands on a number of underlying technologies such as wind turbine aerodynamics, structural dynamics, gearbox design, electrical grid connections, and so on. As wind is the only fuel for wind power plants, naturally, wind......-meteorology and wind-climatology are essential for any utilization of wind energy. This is what we are concerned about here with a view on what has happened in wind energy potential assessments in the last 25 years where the utilization of wind turbines in national power supply has accelerated and what......., The New Worldwide Microscale Wind Resource Assessment Data on IRENA's Global Atlas (The EUDP Global Wind Atlas, 2015)], and finally, the perspective for the current work with the New European Wind Atlas [E. L. Petersen et al., Energy Bull. 17, 34–39 (2014); Environ. Res. Lett. 8(1), 011005 (2013...

  1. 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.

  2. 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.

  3. 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.

  4. Constructing an Interpolated Potential Energy Surface of a Large Molecule: A Case Study with Bacteriochlorophyll a Model in the Fenna-Matthews-Olson Complex.

    Science.gov (United States)

    Kim, Chang Woo; Rhee, Young Min

    2016-11-08

    Constructing a reliable potential energy surface (PES) is a key step toward computationally studying the chemical dynamics of any molecular system. The interpolation scheme is a useful tool that can closely follow the accuracy of quantum chemical means at a dramatically reduced computational cost. However, applying interpolation to building a PES of a large molecule is not a straightforward black-box approach, as it frequently encounters practical difficulties associated with its large dimensionality. Here, we present detailed courses of applying interpolation toward building a PES of a large chromophore molecule. We take the example of S0 and S1 electronic states of bacteriochlorophyll a (BChla) molecules in the Fenna-Matthews-Olson light harvesting complex. With a reduced model molecule that bears BChla's main π-conjugated ring, various practical approaches are designed for improving the PES quality in a stable manner and for fine-tuning the final surface such that the surface can be adopted for long time molecular dynamics simulations. Combined with parallel implementation, we show that interpolated mechanics/molecular mechanics (IM/MM) simulations of the entire complex in the nanosecond time scale can be conducted readily without any practical issues. With 1500 interpolation data points for each chromophore unit, the PES error relative to the reference quantum chemical calculation is found to be ∼0.15 eV in the thermally accessible region of the conformational space, together with ∼0.01 eV error in S0 - S1 transition energies. The performance issue related to the use of a large interpolation database within the framework of our parallel routines is also discussed.

  5. Free-energy calculations using classical molecular simulation: application to the determination of the melting point and chemical potential of a flexible RDX model.

    Science.gov (United States)

    Sellers, Michael S; Lísal, Martin; Brennan, John K

    2016-03-21

    We present an extension of various free-energy methodologies to determine the chemical potential of the solid and liquid phases of a fully-flexible molecule using classical simulation. The methods are applied to the Smith-Bharadwaj atomistic potential representation of cyclotrimethylene trinitramine (RDX), a well-studied energetic material, to accurately determine the solid and liquid phase Gibbs free energies, and the melting point (Tm). We outline an efficient technique to find the absolute chemical potential and melting point of a fully-flexible molecule using one set of simulations to compute the solid absolute chemical potential and one set of simulations to compute the solid-liquid free energy difference. With this combination, only a handful of simulations are needed, whereby the absolute quantities of the chemical potentials are obtained, for use in other property calculations, such as the characterization of crystal polymorphs or the determination of the entropy. Using the LAMMPS molecular simulator, the Frenkel and Ladd and pseudo-supercritical path techniques are adapted to generate 3rd order fits of the solid and liquid chemical potentials. Results yield the thermodynamic melting point Tm = 488.75 K at 1.0 atm. We also validate these calculations and compare this melting point to one obtained from a typical superheated simulation technique.

  6. Energy System Modeling with REopt

    Energy Technology Data Exchange (ETDEWEB)

    Simpkins, Travis; Anderson, Kate; Cutler, Dylan; Olis, Dan; Elgqvist, Emma; DiOrio, Nick; Walker, Andy

    2016-07-15

    This poster details how REopt - NREL's software modeling platform for energy systems integration and optimization - can help to model energy systems. Some benefits of modeling with REopt include optimizing behind the meter storage for cost and resiliency, optimizing lab testing, optimizing dispatch of utility scale storage, and quantifying renewable energy impact on outage survivability.

  7. Rotational Energy Transfer of N2 Gas Determined Using a New Ab Initio Potential Energy Surface

    Science.gov (United States)

    Huo, Winifred M.; Stallcop, James R.; Partridge, Harry; Langhoff, Stephen R. (Technical Monitor)

    1997-01-01

    Rotational energy transfer between two N2 molecules is a fundamental process of some importance. Exchange is expected to play a role, but its importance is somewhat uncertain. Rotational energy transfer cross sections of N2 also have applications in many other fields including modeling of aerodynamic flows, laser operations, and linewidth analysis in nonintrusive laser diagnostics. A number of N2-N2 rigid rotor potential energy surface (PES) has been reported in the literature.

  8. WIND SPEED AND ENERGY POTENTIAL ANALYSES

    Directory of Open Access Journals (Sweden)

    A. TOKGÖZLÜ

    2013-01-01

    Full Text Available This paper provides a case study on application of wavelet techniques to analyze wind speed and energy (renewable and environmental friendly energy. Solar and wind are main sources of energy that allows farmers to have the potential for transferring kinetic energy captured by the wind mill for pumping water, drying crops, heating systems of green houses, rural electrification's or cooking. Larger wind turbines (over 1 MW can pump enough water for small-scale irrigation. This study tried to initiate data gathering process for wavelet analyses, different scale effects and their role on wind speed and direction variations. The wind data gathering system is mounted at latitudes: 37° 50" N; longitude 30° 33" E and height: 1200 m above mean sea level at a hill near Süleyman Demirel University campus. 10 minutes average values of two levels wind speed and direction (10m and 30m above ground level have been recorded by a data logger between July 2001 and February 2002. Wind speed values changed between the range of 0 m/s and 54 m/s. Annual mean speed value is 4.5 m/s at 10 m ground level. Prevalent wind

  9. Development potential of wind energy in Turkey

    Directory of Open Access Journals (Sweden)

    İsmet Akova

    2011-07-01

    energy potential, as part of the renewable energy sources of Turkey, are highly important and each of these two sources has the technical potential to cover the electric production in 2008. The recent increase in the number of wind energy power stations can be related to the preparation of Turkish Wind Atlas, the preparation of legal arrangements to support private sector entrepreneurs and the rise in oil prices. Wind energy power stations are active in Marmara, Aegean region and the Mediterreanean region witnessing more constant and strong winds and are anticipated to be founded in other geographical regions as well in the future.

  10. A Potential Model for Cylindrical Pores

    Institute of Scientific and Technical Information of China (English)

    张现仁; 汪文川

    2001-01-01

    An analytical potential for cylindrical pores has been derived by introducing a variational method into the integration for the calculation of the interaction energy between the wall molecules and a test molecule, all of which are represented by Lennard-Jones potential. The model proposed gives good fit to the results from the cylindrical surface model and the pseudoatom model. To test the potential proposed rigorously, we have carried out grand canonical ensemble Monte Carlo(GCMC) simulation of nitrogen in the MCM-41 pore at 77 K, and compared the simulated adsorption isotherm with the experimental data reported in the literature. The simulated isotherm from our model is in almost qualitative agreement with experiment. Consequently, the model proposed provides an explicit and accurate description of cylindrical pores represented by the Lennard-Jones potential. Moreover, the model can be easily applied to a variety of cylindrical pores, ranging from cylindrical surface to finite thickness walls, in both theoretical studies and computer simulations.

  11. Design tool for the thermal energy potential of asphalt pavements

    NARCIS (Netherlands)

    Loomans, M.G.L.C.; Oversloot, H.P.; Bondt, A. de; Jansen, R.; Rij, H. van

    2003-01-01

    This paper describes the development of a design tool for the calculation of the thermal energy potential of a so-called asphalt collector. Two types of numerical models have been developed and validated against experimental results from a full-scale test-site. The validation showed to be a tedious

  12. Low-energy K- optical potentials: deep or shallow?

    Science.gov (United States)

    Cieplý, A.; Friedman, E.; Gal, A.; Mareš, J.

    2001-12-01

    The K- optical potential in the nuclear medium is evaluated self consistently from a free-space K-Nt matrix constructed within a coupled-channel chiral approach. The fit of model parameters gives a good description of the low-energy data plus the available K- atomic data. The resulting optical potential is relatively `shallow' in contradiction to the potentials obtained from phenomenological analysis. The calculated (Kstop-,π) hypernuclear production rates are very sensitive to the details of kaonic bound state wave function. The (Kstop-,π) reaction could thus serve as a suitable tool to distinguish between shallow and deep K- optical potentials.

  13. Theoretical studies of potential energy surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Harding, L.B. [Argonne National Laboratory, IL (United States)

    1993-12-01

    The goal of this program is to calculate accurate potential energy surfaces (PES) for both reactive and nonreactive systems. To do this the electronic Schrodinger equation must be solved. Our approach to this problem starts with multiconfiguration self-consistent field (MCSCF) reference wavefunctions. These reference wavefunctions are designed to be sufficiently flexible to accurately describe changes in electronic structure over a broad range of geometries. Electron correlation effects are included via multireference, singles and doubles configuration interaction (MRSDCI) calculations. With this approach, the authors are able to provide useful predictions of the energetics for a broad range of systems.

  14. An adaptive interpolation scheme for molecular potential energy surfaces

    Science.gov (United States)

    Kowalewski, Markus; Larsson, Elisabeth; Heryudono, Alfa

    2016-08-01

    The calculation of potential energy surfaces for quantum dynamics can be a time consuming task—especially when a high level of theory for the electronic structure calculation is required. We propose an adaptive interpolation algorithm based on polyharmonic splines combined with a partition of unity approach. The adaptive node refinement allows to greatly reduce the number of sample points by employing a local error estimate. The algorithm and its scaling behavior are evaluated for a model function in 2, 3, and 4 dimensions. The developed algorithm allows for a more rapid and reliable interpolation of a potential energy surface within a given accuracy compared to the non-adaptive version.

  15. An adaptive interpolation scheme for molecular potential energy surfaces

    CERN Document Server

    Kowalewski, Markus; Heryudono, Alfa

    2016-01-01

    The calculation of potential energy surfaces for quantum dynamics can be a time consuming task -- especially when a high level of theory for the electronic structure calculation is required. We propose an adaptive interpolation algorithm based on polyharmonic splines combined with a partition of unity approach. The adaptive node refinement allows to greatly reduce the number of sample points by employing a local error estimate. The algorithm and its scaling behavior is evaluated for a model function in 2, 3 and 4 dimensions. The developed algorithm allows for a more rapid and reliable interpolation of a potential energy surface within a given accuracy compared to the non-adaptive version.

  16. On the use of big-bang method to generate low-energy structures of atomic clusters modeled with pair potentials of different ranges.

    Science.gov (United States)

    Marques, J M C; Pais, A A C C; Abreu, P E

    2012-02-05

    The efficiency of the so-called big-bang method for the optimization of atomic clusters is analysed in detail for Morse pair potentials with different ranges; here, we have used Morse potentials with four different ranges, from long- ρ = 3) to short-ranged ρ = 14) interactions. Specifically, we study the efficacy of the method in discovering low-energy structures, including the putative global minimum, as a function of the potential range and the cluster size. A new global minimum structure for long-ranged ρ = 3) Morse potential at the cluster size of n= 240 is reported. The present results are useful to assess the maximum cluster size for each type of interaction where the global minimum can be discovered with a limited number of big-bang trials.

  17. Three-dimensional potential energy surface of Ar–CO

    Energy Technology Data Exchange (ETDEWEB)

    Sumiyoshi, Yoshihiro, E-mail: y-sumiyoshi@gunma-u.ac.jp [Division of Pure and Applied Science, Graduate School of Science and Technology, Gunma University, 4-2 Aramaki, Maebashi, Gunma 371-8510 (Japan); Endo, Yasuki [Department of Basic Science, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902 (Japan)

    2015-01-14

    A three-dimensional intermolecular potential energy surface of the Ar–CO complex has been determined by fitting most of the previously reported spectroscopic data, where observed transition frequencies by microwave, millimeter-wave, submillimeter-wave, and infrared spectroscopy were reproduced simultaneously within their experimental accuracies. A free rotor model Hamiltonian considering all the freedom of motions for an atom-diatom system was applied to calculate vibration-rotation energies. A three-dimensional potential energy surface obtained by ab initio calculations at the CCSD(T)-F12b/aug-cc-pV5Z level of theory was parameterized by a model function consisting of 46 parameters. They were used as initial values for the least-squares analysis of the experimental data. A total of 20 parameters were optimized to reproduce all the spectroscopic data.

  18. Potential for natural evaporation as a reliable renewable energy resource.

    Science.gov (United States)

    Cavusoglu, Ahmet-Hamdi; Chen, Xi; Gentine, Pierre; Sahin, Ozgur

    2017-09-26

    About 50% of the solar energy absorbed at the Earth's surface drives evaporation, fueling the water cycle that affects various renewable energy resources, such as wind and hydropower. Recent advances demonstrate our nascent ability to convert evaporation energy into work, yet there is little understanding about the potential of this resource. Here we study the energy available from natural evaporation to predict the potential of this ubiquitous resource. We find that natural evaporation from open water surfaces could provide power densities comparable to current wind and solar technologies while cutting evaporative water losses by nearly half. We estimate up to 325 GW of power is potentially available in the United States. Strikingly, water's large heat capacity is sufficient to control power output by storing excess energy when demand is low, thus reducing intermittency and improving reliability. Our findings motivate the improvement of materials and devices that convert energy from evaporation.The evaporation of water represents an alternative source of renewable energy. Building on previous models of evaporation, Cavusoglu et al. show that the power available from this natural resource is comparable to wind and solar power, yet it does not suffer as much from varying weather conditions.

  19. Baby Skyrme models without a potential term

    CERN Document Server

    Ashcroft, Jennifer; Krusch, Steffen

    2015-01-01

    We develop a one-parameter family of static baby Skyrme models that do not require a potential term to admit topological solitons. This is a novel property as all currently known baby Skyrme models must contain a potential term in order to have stable soliton solutions, though the Skyrme model does not require this. Our new models satisfy an energy bound that is linear in terms of the topological charge and can be saturated in an extreme limit. They also satisfy a virial theorem that is shared by the Skyrme model. We calculate the solitons of our new models numerically and observe that their form depends significantly on the choice of parameter. In one extreme, we find compactons whilst at the other there is a scale invariant model in which solitons can be obtained exactly as solutions to a Bogomolny equation. We provide an initial investigation into these solitons and compare them with the baby Skyrmions of other models.

  20. The Wind Energy Potential of Kurdistan, Iran.

    Science.gov (United States)

    Arefi, Farzad; Moshtagh, Jamal; Moradi, Mohammad

    2014-01-01

    In the current work by using statistical methods and available software, the wind energy assessment of prone regions for installation of wind turbines in, Qorveh, has been investigated. Information was obtained from weather stations of Baneh, Bijar, Zarina, Saqez, Sanandaj, Qorveh, and Marivan. The monthly average and maximum of wind speed were investigated between the years 2000-2010 and the related curves were drawn. The Golobad curve (direction and percentage of dominant wind and calm wind as monthly rate) between the years 1997-2000 was analyzed and drawn with plot software. The ten-minute speed (at 10, 30, and 60 m height) and direction (at 37.5 and 10 m height) wind data were collected from weather stations of Iranian new energy organization. The wind speed distribution during one year was evaluated by using Weibull probability density function (two-parametrical), and the Weibull curve histograms were drawn by MATLAB software. According to the average wind speed of stations and technical specifications of the types of turbines, the suitable wind turbine for the station was selected. Finally, the Divandareh and Qorveh sites with favorable potential were considered for installation of wind turbines and construction of wind farms.

  1. Inventory of state energy models

    Energy Technology Data Exchange (ETDEWEB)

    Melcher, A.G.; Gist, R.L.; Underwood, R.G.; Weber, J.C.

    1980-03-31

    These models address a variety of purposes, such as supply or demand of energy or of certain types of energy, emergency management of energy, conservation in end uses of energy, and economic factors. Fifty-one models are briefly described as to: purpose; energy system; applications;status; validation; outputs by sector, energy type, economic and physical units, geographic area, and time frame; structure and modeling techniques; submodels; working assumptions; inputs; data sources; related models; costs; references; and contacts. Discussions in the report include: project purposes and methods of research, state energy modeling in general, model types and terminology, and Federal legislation to which state modeling is relevant. Also, a state-by-state listing of modeling efforts is provided and other model inventories are identified. The report includes a brief encylopedia of terms used in energy models. It is assumed that many readers of the report will not be experienced in the technical aspects of modeling. The project was accomplished by telephone conversations and document review by a team from the Colorado School of Mines Research Institute and the faculty of the Colorado School of Mines. A Technical Committee (listed in the report) provided advice during the course of the project.

  2. POTENTIAL FOR WASTEWATER MANAGEMENT USING ENERGY CROPS

    Directory of Open Access Journals (Sweden)

    Alistair R. McCRACKEN

    2015-04-01

    Full Text Available In most countries within Europe there are numerous small rural Waste Water Treatment Works (WWTWs often serving a small number of people equivalents (PEs. It is usually impractical and expensive to upgrade such WWTWs and yet they are often delivering potentially highly polluting effluent into streams and rivers. Short Rotation Coppice (SRC willow, grown as an energy source, may be an ideal crop for the bioremediation of a variety of effluents and wastewater streams. As part of an EU funded (INTERREG IVA project called ANSWER (Agricultural Need for Sustainable Willow Effluent Recycling four Proof of Concept irrigation schemes were established ranging in size from 5 to 15 ha. One of the larger of these at Bridgend, Co. Donegal, Republic of Ireland was planted in spring 2013 and has been irrigated with municipal effluent since June 2014. Over 19,000 m3 of effluent has been applied to the willow thus preventing 617 kg N and 28.5 kg P from being discharged to a neighbouring stream. Using SRC willow for the bioremediation of effluent from small rural WWWTs offers a sustainable, cost-effective and practical solution to wastewater management in many countries. There may be also potential to use willow for the bioremediation of landfill leachates, within the footprint of the landfill site.

  3. Role and potential of renewable energy and energy efficiency for global energy supply

    Energy Technology Data Exchange (ETDEWEB)

    Krewitt, Wolfram; Nienhaus, Kristina [German Aerospace Center e.V. (DLR), Stuttgart (Germany); Klessmann, Corinna; Capone, Carolin; Stricker, Eva [Ecofys Germany GmbH, Berlin (Germany); Graus, Wina; Hoogwijk, Monique [Ecofys Netherlands BV, Utrecht (Netherlands); Supersberger, Nikolaus; Winterfeld, Uta von; Samadi, Sascha [Wuppertal Institute for Climate, Environment and Energy GmbH, Wuppertal (Germany)

    2009-12-15

    The analysis of different global energy scenarios in part I of the report confirms that the exploitation of energy efficiency potentials and the use of renewable energies play a key role in reaching global CO2 reduction targets. An assessment on the basis of a broad literature research in part II shows that the technical potentials of renewable energy technologies are a multiple of today's global final energy consumption. The analysis of cost estimates for renewable electricity generation technologies and even long term cost projections across the key studies in part III demonstrates that assumptions are in reasonable agreement. In part IV it is shown that by implementing technical potentials for energy efficiency improvements in demand and supply sectors by 2050 can be limited to 48% of primary energy supply in IEA's ''Energy Technology Perspectives'' baseline scenario. It was found that a large potential for cost-effective measures exists, equivalent to around 55-60% of energy savings of all included efficiency measures (part V). The results of the analysis on behavioural changes in part VI show that behavioural dimensions are not sufficiently included in energy scenarios. Accordingly major research challenges are revealed. (orig.)

  4. Impacts of Model Building Energy Codes

    Energy Technology Data Exchange (ETDEWEB)

    Athalye, Rahul A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Sivaraman, Deepak [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Elliott, Douglas B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Liu, Bing [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bartlett, Rosemarie [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-10-31

    The U.S. Department of Energy (DOE) Building Energy Codes Program (BECP) periodically evaluates national and state-level impacts associated with energy codes in residential and commercial buildings. Pacific Northwest National Laboratory (PNNL), funded by DOE, conducted an assessment of the prospective impacts of national model building energy codes from 2010 through 2040. A previous PNNL study evaluated the impact of the Building Energy Codes Program; this study looked more broadly at overall code impacts. This report describes the methodology used for the assessment and presents the impacts in terms of energy savings, consumer cost savings, and reduced CO2 emissions at the state level and at aggregated levels. This analysis does not represent all potential savings from energy codes in the U.S. because it excludes several states which have codes which are fundamentally different from the national model energy codes or which do not have state-wide codes. Energy codes follow a three-phase cycle that starts with the development of a new model code, proceeds with the adoption of the new code by states and local jurisdictions, and finishes when buildings comply with the code. The development of new model code editions creates the potential for increased energy savings. After a new model code is adopted, potential savings are realized in the field when new buildings (or additions and alterations) are constructed to comply with the new code. Delayed adoption of a model code and incomplete compliance with the code’s requirements erode potential savings. The contributions of all three phases are crucial to the overall impact of codes, and are considered in this assessment.

  5. The potential impact of hydrogen energy use on the atmosphere

    Science.gov (United States)

    van Ruijven, B. J.; Lamarque, J. F.; van Vuuren, D. P.; Kram, T.; Eerens, H.

    2009-04-01

    Energy models show very different trajectories for future energy systems (partly as function of future climate policy). One possible option is a transition towards a hydrogen-based energy system. The potential impact of such hydrogen economy on atmospheric emissions is highly uncertain. On the one hand, application of hydrogen in clean fuel cells reduces emissions of local air pollutants, like SOx and NOx. On the other hand, emissions of hydrogen from system leakages are expected to change the atmospheric concentrations and behaviour (see also Price et al., 2007; Sanderson et al., 2003; Schultz et al., 2003; Tromp et al., 2003). The uncertainty arises from several sources: the expected use of hydrogen, the intensity of leakages and emissions, and the atmospheric chemical behaviour of hydrogen. Existing studies to the potential impacts of a hydrogen economy on the atmosphere mostly use hydrogen emission scenarios that are based on simple assumptions. This research combines two different modelling efforts to explore the range of impacts of hydrogen on atmospheric chemistry. First, the potential role of hydrogen in the global energy system and the related emissions of hydrogen and other air pollutants are derived from the global energy system simulation model TIMER (van Vuuren, 2007). A set of dedicated scenarios on hydrogen technology development explores the most pessimistic and optimistic cases for hydrogen deployment (van Ruijven et al., 2008; van Ruijven et al., 2007). These scenarios are combined with different assumptions on hydrogen emission factors. Second, the emissions from the TIMER model are linked to the NCAR atmospheric model (Lamarque et al., 2005; Lamarque et al., 2008), in order to determine the impacts on atmospheric chemistry. By combining an energy system model and an atmospheric model, we are able to consistently explore the boundaries of both hydrogen use, emissions and impacts on atmospheric chemistry. References: Lamarque, J.-F., Kiehl, J. T

  6. Objective information about energy models

    Energy Technology Data Exchange (ETDEWEB)

    Hale, D.R. (Energy Information Administration, Washington, DC (United States))

    1993-01-01

    This article describes the Energy Information Administration's program to develop objective information about its modeling systems without hindering model development and applications, and within budget and human resource constraints. 16 refs., 1 fig., 2 tabs.

  7. Dynamic energy budget modeling reveals the potential of future growth and calcification for the coccolithophore Emiliania huxleyi in an acidified ocean.

    Science.gov (United States)

    Muller, Erik B; Nisbet, Roger M

    2014-06-01

    Ocean acidification is likely to impact the calcification potential of marine organisms. In part due to the covarying nature of the ocean carbonate system components, including pH and CO2 and CO3(2-) levels, it remains largely unclear how each of these components may affect calcification rates quantitatively. We develop a process-based bioenergetic model that explains how several components of the ocean carbonate system collectively affect growth and calcification rates in Emiliania huxleyi, which plays a major role in marine primary production and biogeochemical carbon cycling. The model predicts that under the IPCC A2 emission scenario, its growth and calcification potential will have decreased by the end of the century, although those reductions are relatively modest. We anticipate that our model will be relevant for many other marine calcifying organisms, and that it can be used to improve our understanding of the impact of climate change on marine systems.

  8. An improved model electronic Hamiltonian for potential energy surfaces and spin-orbit couplings of low-lying d-d states of [Fe(bpy)3]2+.

    Science.gov (United States)

    Iuchi, Satoru; Koga, Nobuaki

    2014-01-14

    With the aim of exploring excited state dynamics, a model electronic Hamiltonian for several low-lying d-d states of [Fe(bpy)3](2+) complex [S. Iuchi, J. Chem. Phys. 136, 064519 (2012)] is refined using density-functional theory calculations of singlet, triplet, and quintet states as benchmarks. Spin-orbit coupling elements are also evaluated within the framework of the model Hamiltonian. The accuracy of the developed model Hamiltonian is determined by examining potential energies and spin-orbit couplings at surface crossing regions between different spin states. Insights into the potential energy surfaces around surface crossing regions are also provided through molecular dynamics simulations. The results demonstrate that the constructed model Hamiltonian can be used for studies on the d-d excited state dynamics of [Fe(bpy)3](2+).

  9. Energy potential of region and its quantitative assessment

    Directory of Open Access Journals (Sweden)

    Tatyana Aleksandrovna Kovalenko

    2013-09-01

    Full Text Available The purpose of the article is the development of the concept of the energy potential of the region (EPR, the analysis of the existing structure of relationships for the EPR elements in Ukraine and improvement of a quantitative assessment of energy potential of the region (country. The methods of an assessment of the existing condition of energy potential of the territory are the subject matter of the research. As a result of the analysis of concept’s definitions of energy potential of the region, it has further development and included the consumer potential of energy resources and capacity of management. The structure of relationships between elements of energy potential is developed for the Ukraine region. The new economic indicator — the realized energy potential is offered for an EPR assessment. By means of this indicator, the assessment of energy potential for the different countries of the world and a number of Ukraine areas of is performed.

  10. 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......, 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...

  11. Potential for energy technologies in residential and commercial buildings

    Energy Technology Data Exchange (ETDEWEB)

    Glesk, M.M.

    1979-11-01

    The residential-commercial energy technology model was developed as a planning tool for policy analysis in the residential and commercial building sectors. The model and its procedures represent a detailed approach to estimating the future acceptance of energy-using technologies both in new construction and for retrofit into existing buildings. The model organizes into an analytical framework all relevant information and data on building energy technology, building markets, and government policy, and it allows for easy identification of the relative importance of key assumptions. The outputs include estimates of the degree of penetration of the various building energy technologies, the levels of energy use savings associated with them, and their costs - both private and government. The model was designed to estimate the annual energy savings associated with new technologies compared with continued use of conventional technology at 1975 levels. The amount of energy used under 1975 technology conditions is referred to as the reference case energy use. For analytical purposes the technologies were consolidated into ten groupings: electric and gas heat pumps; conservation categories I, II, and III; solar thermal (hot water, heating, and cooling); photovoltaics, and wind systems. These groupings clearly do not allow an assessment of the potential for individual technologies, but they do allow a reasonable comparison of their roles in the R/C sector. Assumptions were made regarding the technical and economic performances of the technologies over the period of the analysis. In addition, the study assessed the non-financial characteristics of the technologies - aesthetics, maintenance complexity, reliability, etc. - that will also influence their market acceptability.

  12. Study of chirally motivated low-energy K - optical potentials

    Science.gov (United States)

    Cieplý, A.; Friedman, E.; Gal, A.; Mareš, J.

    2001-12-01

    The K - optical potential in the nuclear medium is evaluated self consistently from a free-space K -N t matrix constructed within a coupled-channel chiral approach to the low-energy K¯N data. The chiral-model parameters are fitted to a select subset of the low-energy data plus the K - atomic data throughout the periodic table. The resulting attractive K - optical potentials are relatively 'shallow', with central depth of the real part about 55 MeV, for a fairly reasonable reproduction of the atomic data with χ2/ N≈2.2. Relatively 'deep' attractive potentials of depth about 180 MeV, which result in other phenomenological approaches with χ2/ N≈1.5, are ruled out within chirally motivated models. Different physical data input is required to distinguish between shallow and deep K - optical potentials. The (K -stop, π) reaction could provide such a test, with exclusive rates differing by over a factor of three for the two classes of potentials. Finally, forward (K -,p) differential cross sections for the production of relatively narrow deeply bound K -nuclear states are evaluated for deep K - optical potentials, yielding values considerably lower than those estimated before.

  13. Alaska's renewable energy potential.

    Energy Technology Data Exchange (ETDEWEB)

    2009-02-01

    This paper delivers a brief survey of renewable energy technologies applicable to Alaska's climate, latitude, geography, and geology. We first identify Alaska's natural renewable energy resources and which renewable energy technologies would be most productive. e survey the current state of renewable energy technologies and research efforts within the U.S. and, where appropriate, internationally. We also present information on the current state of Alaska's renewable energy assets, incentives, and commercial enterprises. Finally, we escribe places where research efforts at Sandia National Laboratories could assist the state of Alaska with its renewable energy technology investment efforts.

  14. Transient accelerating scalar models with exponential potentials

    Institute of Scientific and Technical Information of China (English)

    Wen-Ping Cui; Yang Zhang; Zheng-Wen Fu

    2013-01-01

    We study a known class of scalar dark energy models in which the potential has an exponential term and the current accelerating era is transient.We find that,although a decelerating era will return in the future,when extrapolating the model back to earlier stages (z(≥) 4),scalar dark energy becomes dominant over matter.So these models do not have the desired tracking behavior,and the predicted transient period of acceleration cannot be adopted into the standard scenario of the Big Bang cosmology.When couplings between the scalar field and matter are introduced,the models still have the same problem; only the time when deceleration returns will be varied.To achieve re-deceleration,one has to turn to alternative models that are consistent with the standard Big Bang scenario.

  15. Potential energy savings and thermal comfort

    DEFF Research Database (Denmark)

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

    1996-01-01

    Results of simulations carried out on four different buildings with common windows, commercial low-energy windows and xerogel windows are presented. The results are the annual energy consumption for space heating and the indoor air temperature level....

  16. Renewable Energy Potential for New Mexico

    Science.gov (United States)

    RE-Powering America's Land: Renewable Energy on Contaminated Land and Mining Sites was presented by Penelope McDaniel, during the 2008 Brown to Green: Make the Connection to Renewable Energy workshop.

  17. 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.

  18. Energy demand modeling for Uzbekistan

    Directory of Open Access Journals (Sweden)

    Bobur Khodjaev

    2012-05-01

    Full Text Available The paper is devoted to energy demand forecasting in Uzbekistan. Studies show that in spite of the abundant reserves of hydrocarbons, low energy efficiency can have an adverse impact on energy security in Uzbekistan in the future. Oil and gas are the main primary energy source and they ensure energy security of Uzbekistan. Energy demand forecasting is essential in order to develop an effective energy policy. Such forecast can be useful to plan oil and gas production volumes, to identify priorities for the industrial modernization and to create favorable conditions for sustainable economic development in the future. Author proposes model based on translog function for developing medium-and long-term development programs in energy sector and the modernization and technological re-equipment of industry.

  19. Performance-based potential for residential energy efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Performance-based potential for residential energy efficiency

    2013-01-15

    Energy performance contracts (EPCs) have proven an effective mechanism for increasing energy efficiency in nearly all sectors of the economy since their introduction nearly 30 years ago. In the modern form, activities undertaken as part of an EPC are scoped and implemented by experts with specialized technical knowledge, financed by commercial lenders, and enable a facility owner to limit risk and investment of time and resources while receiving the rewards of improved energy performance. This report provides a review of the experiences of the US with EPCs and discusses the possibilities for the residential sector to utilize EPCs. Notably absent from the EPC market is the residential segment. Historically, research has shown that the residential sector varies in several key ways from markets segments where EPCs have proven successful, including: high degree of heterogeneity of energy use characteristics among and within households, comparatively small quantity of energy consumed per residence, limited access to information about energy consumption and savings potential, and market inefficiencies that constrain the value of efficiency measures. However, the combination of recent technological advances in automated metering infrastructure, flexible financing options, and the expansion of competitive wholesale electricity markets to include energy efficiency as a biddable supply-side resource present an opportunity for EPC-like efforts to successfully engage the residential sector, albeit following a different model than has been used in EPCs traditionally.(Author)

  20. A complete map of the ion chemistry of the naphthalene radical cation? DFT and RRKM modeling of a complex potential energy surface

    Energy Technology Data Exchange (ETDEWEB)

    Solano, Eduardo A.; Mayer, Paul M., E-mail: pmmayer@uottawa.ca [Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Ontario K1N 6N5 (Canada)

    2015-09-14

    The fragmentation mechanisms of the naphthalene molecular ion to [M–C{sub 4}H{sub 2}]{sup +•}, [M–C{sub 2}H{sub 2}]{sup +•}, [M–H{sub 2}]{sup +•}, and [M–H{sup •}]{sup +} were obtained at the UB3LYP/6-311+G(3df,2p)//UB3LYP/6-31G(d) level of theory and were subsequently used to calculate the microcanonical rate constants, k(E)’s, for all the steps by the Rice-Ramsperger-Kassel-Marcus formalism. The pre-equilibrium and steady state approximations were applied on different regions of the potential energy profiles to obtain the fragmentation k(E)’s and calculate the relative abundances of the ions as a function of energy. These results reproduce acceptably well the imaging photoelectron-photoion coincidence spectra of naphthalene, in the photon-energy range 14.0–18.8 eV that was previously reported by our group. Prior to dissociation, the molecular ion rapidly equilibrates with a set of isomers that includes the Z- and E-phenylvinylacetylene (PVA) radical cations. The naphthalene ion is the predominant isomer below 10 eV internal energy, with the other isomers remaining at steady state concentrations. Later on, new steady-state intermediates are formed, such as the azulene and 1-phenyl-butatriene radical cations. The naphthalene ion does not eject an H atom directly but eliminates an H{sub 2} molecule in a two-step fragmentation. H{sup •} loss occurs instead from the 1-phenyl-butatriene ion. The PVA ions initiate the ejection of diacetylene (C{sub 4}H{sub 2}) to yield the benzene radical cation. Acetylene elimination yields the pentalene cation at low energies (where it can account for 45.9%–100.0% of the rate constant of this channel), in a three-step mechanism starting from the azulene ion. However, above 7.6 eV, the major [M–C{sub 2}H{sub 2}]{sup +•} structure is the phenylacetylene cation.

  1. Calculation of Electron Beam Potential Energy from RF Photocathode Gun

    CERN Document Server

    Liu Wan Ming; Power, John G; Wang, Haitao

    2005-01-01

    In this paper, we consider the contribution of potential energy to beam dynamics as simulated by PARMELA at low energies (10 - 30MeV). We have developed a routine to calculate the potential energy of the relativistic electron beam using the static coulomb potential in the rest frame (first order approximation as in PARMELA). We found that the potential energy contribution to the beam dynamics could be very significant, particularly with high charge beams generated by an RF photocathode gun. Our results show that when the potential energy is counted correctly and added to the kinetic energy from PARMELA, the total energy is conserved. Simulation results of potential and kinetic energies for short beams (~1 mm) at various charges (1 - 100 nC) generated by a high current RF photocathode gun are presented.

  2. User behaviour impact on energy savings potential

    DEFF Research Database (Denmark)

    Rose, Jørgen

    2014-01-01

    corresponding to different levels of energy consumption. The purpose of the analysis is to identify the importance of each of the four primary user-related parameters in terms of their relative and combined impact on the overall energy needs before/after upgrading; 1) Indoor temperature, 2) Internal heat gain......, 3) Domestic hot water consumption and 4) Air change rate. Based on the analysis, a methodology is established that can be used to make more realistic and accurate predictions of expected energy savings associated with energy upgrading taking into account user behaviour....

  3. Singularity Problem in Teleparallel Dark Energy Models

    CERN Document Server

    Geng, Chao-Qiang; Lee, Chung-Chi

    2013-01-01

    We study the singularity problem in teleparallel dark energy models. A future singularity may occur due to the non-minimal coupling of the dark energy scalar field to teleparallel gravity that effectively changes the gravitational coupling strength and can even make it diverge. This singularity may be avoided by a binding-type self-potential that keeps the scalar field away from the singularity point. For demonstration we analyze the model with a quadratic potential and show how the (non)occurrence of the singularity depends on the initial conditions and the steepness of the potential, both of which affect the competition between the self-interaction and the non-minimal coupling. To examine the capability of the binding-type potential to fit observational data and meanwhile to avoid the singularity, we perform the data fitting for this model and show that the observationally viable region up to the $3\\sigma$ confidence level is free of the future singularity.

  4. The Potential For Energy Efficiency In The State of Iowa

    Energy Technology Data Exchange (ETDEWEB)

    Hadley, SW

    2001-12-05

    The purpose of this study was to do an initial estimate of the potential for energy savings in the state of Iowa. Several methods for determining savings were examined, including existing programs, surveys, savings calculators, and economic simulation. Each method has advantages and disadvantages, trading off between detail of information, accuracy of results, and scope. This paper concentrated on using economic simulation (the NEMS model (EIA 2000a)) to determine market potential for energy savings for the residential and commercial sectors. The results of surveys were used to calculate the economic potential for savings in the industrial sector. The NEMS model is used by the Energy Information Administration to calculate twenty-year projections of energy use for every region of the country. The results of the Annual Energy Outlook 2000 were used as the Base case (EIA 1999a). Two alternative cases were created to simulate energy savings policies. Voluntary, market-related programs were simulated by lowering the effective discount rates that end-users use when making decisions on equipment purchases. Standards programs in the residential sector were simulated by eliminating the availability of low efficiency equipment in future years. The parameters for these programs were based on the Moderate scenario from the DOE Clean Energy Futures study (Interlaboratory Working Group 2000), which assumed increased concern by society on energy efficiency but not to the point of fiscal policies such as taxes or direct subsidies. The study only considered a subset of the various programs, policies, and technologies that could reduce energy use. The major end-uses in the residential sector affected by the policies were space cooling (20% savings by 2020) and water heating (14% savings by 2020.) Figure S-1 shows the space cooling savings when voluntary programs and minimum efficiency standards were implemented. Refrigerators, freezers, and clothes dryers saw slight improvements

  5. Energy Efficiency Improvement Potential in Historical Brick Building

    OpenAIRE

    Žogla, Gatis; Blumberga, Andra; Zvaigznītis, Kristaps; Dzikēvičs, Miķelis; Blumberga, Dagnija; Burinskiene, Marija

    2013-01-01

    Energy efficiency in historical heritage buildings is viewed as a taboo because these buildings usually are law-protected and no energy efficiency measures that would change the appearance of building are allowed. In this paper we look at a potential of increasing energy efficiency level in historical buildings. Measurements to determine energy efficiency of a historical brick building have been done, which also give the possibility to determine the potential of energy efficiency measures in ...

  6. Energy conservation potential of surface modification technologies

    Energy Technology Data Exchange (ETDEWEB)

    Le, H.K.; Horne, D.M.; Silberglitt, R.S.

    1985-09-01

    This report assesses the energy conservation impact of surface modification technologies on the metalworking industries. The energy conservation impact of surface modification technologies on the metalworking industries is assessed by estimating their friction and wear tribological sinks and the subsequent reduction in these sinks when surface modified tools are used. Ion implantation, coatings, and laser and electron beam surface modifications are considered.

  7. Regions in Energy Market Models

    Energy Technology Data Exchange (ETDEWEB)

    Short, W.

    2007-02-01

    This report explores the different options for spatial resolution of an energy market model--and the advantages and disadvantages of models with fine spatial resolution. It examines different options for capturing spatial variations, considers the tradeoffs between them, and presents a few examples from one particular model that has been run at different levels of spatial resolution.

  8. Regions in Energy Market Models

    Energy Technology Data Exchange (ETDEWEB)

    None

    2009-01-18

    This report explores the different options for spatial resolution of an energy market model and the advantages and disadvantages of models with fine spatial resolution. It examines different options for capturing spatial variations, considers the tradeoffs between them, and presents a few examples from one particular model that has been run at different levels of spatial resolution.

  9. Rapid Energy Modeling Workflow Demonstration

    Science.gov (United States)

    2013-10-31

    sustainable building . Models produced through the REM process can be updated and accessed continually, thus allowing energy managers to continuously explore...time and cost of audits 4. Review the energy analysis findings under the High Performance and Sustainable Building Guiding Principles Compliance

  10. Cosmological constraints on superconducting dark energy models

    CERN Document Server

    Keresztes, Zoltán; Harko, Tiberiu; Liang, Shi-Dong

    2015-01-01

    We consider cosmological tests of a scalar-vector-tensor gravitational model, in which the dark energy is included in the total action through a gauge invariant, electromagnetic type contribution. The ground state of dark energy, corresponding to a constant potential $V$ is a Bose-Einstein type condensate with spontaneously broken U(1) symmetry. In another words dark energy appears as a massive vector field emerging from a superposition of a massless vector and a scalar field, the latter corresponding to the Goldstone boson. Two particular cosmological models, corresponding to pure electric and pure magnetic type potentials, respectively are confronted with Type IA Supernovae and Hubble parameter data. In the electric case good fit is obtained along a narrow inclined stripe in the $\\Omega _{m}-\\Omega _{V}$ parameter plane, which includes the $\\Lambda $CDM limit. The other points on this admissible region represent superconducting dark energy as a sum of a cosmological constant and a time-evolving contribution...

  11. The quasi-Gaussian entropy theory : Free energy calculations based on the potential energy distribution function

    NARCIS (Netherlands)

    Amadei, A; Apol, MEF; DiNola, A; Berendsen, HJC

    1996-01-01

    A new theory is presented for calculating the Helmholtz free energy based on the potential energy distribution function. The usual expressions of free energy, internal energy and entropy involving the partition function are rephrased in terms of the potential energy distribution function, which must

  12. The quasi-Gaussian entropy theory : Free energy calculations based on the potential energy distribution function

    NARCIS (Netherlands)

    Amadei, A; Apol, MEF; DiNola, A; Berendsen, HJC

    1996-01-01

    A new theory is presented for calculating the Helmholtz free energy based on the potential energy distribution function. The usual expressions of free energy, internal energy and entropy involving the partition function are rephrased in terms of the potential energy distribution function, which must

  13. Energy performance contracting - energy saving potential of selected energy conservation measures (ECM)

    Energy Technology Data Exchange (ETDEWEB)

    Johansson, M. (Dansk Energi Analyse A/S, Frederiksberg (Denmark)); Langkilde, G.; Olesen, Bjarne W. (Technical Univ. of Denmark, ICIEE, Kgs. Lyngby (Denmark)); Moerck, O. (Cenergia Energy Consultants, Herlev (Denmark)); Sundman, O. (DONG Energy, Copenhagen (Denmark)); Engelund Thomsen, K. (Aalborg Univ., SBi, Hoersholm (Denmark))

    2008-09-15

    This report has been developed under the research project 'Etablering af grundlag for energitjenester i Danmark' (project number: ENS-33031-0185) under the Danish research programme - EFP. The objective of this project has been to contribute to the utilisation of the large potential for energy conservations in the building sector within the public, industry and service sectors through the development of a better basis for decision making for both the Energy Service Companies (ESCOes) and the building owners. The EU directive on Energy Service Contracting points at the buildings as the area where the biggest potential market for energy services and energy efficiency improvements are. The EFP-project has two parts: (1) A Danish part and (2) participation in the international cooperation project 'Holistic Assesment Tool-Kit on Energy Efficient Retrofit Measures for Government Buildings (EnERGo)', Annex 46 under the IEA R and D program 'Energy Conservation In Buildings And Community Systems' (ECBCS). This report describes the Danish contributions to the IEA projects subtask B, which has a primary objective to develop a database of energy conservation measures (ECM) with descriptions and performance characteristics of these. (au)

  14. Examining fine potential energy effects in high-energy fission dynamics

    Science.gov (United States)

    Mazurek, K.; Schmitt, C.; Nadtochy, P. N.; Kmiecik, M.; Maj, A.; Wasiak, P.; Wieleczko, J. P.

    2013-11-01

    The potential energy surface plays a decisive role in nuclear fission. Together with inertia and viscosity, it influences the trajectory of the system, and the properties of the fission fragments result from the puzzling interplay between static and dynamical effects. A careful study on the influence of the parametrization of the potential energy landscape in heavy-ion-induced fission is performed. Dynamical calculations are done within the stochastic Langevin approach in a three-dimensional deformation space. Various prescriptions of the potential energy surface are considered, probing two different Liquid Drop models and the deformation dependence of the Wigner/congruence energy. A wide set of observables, including cross sections, particle multiplicities, and integral, as well as isotopic and isobaric, distributions of fission and evaporation products, is analyzed. Nuclei close to the Businaro-Gallone point are confirmed to be well suited for investigating the Liquid Drop parametrization, while the influence of the deformation-dependent Wigner/congruence energy is difficult to demonstrate unambiguously in fission at high excitation energies.

  15. Simple model of stacking-fault energies

    DEFF Research Database (Denmark)

    Stokbro, Kurt; Jacobsen, Lærke Wedel

    1993-01-01

    -density calculations of stacking-fault energies, and gives a simple way of understanding the calculated energy contributions from the different atomic layers in the stacking-fault region. The two parameters in the model describe the relative energy contributions of the s and d electrons in the noble and transition......A simple model for the energetics of stacking faults in fcc metals is constructed. The model contains third-nearest-neighbor pairwise interactions and a term involving the fourth moment of the electronic density of states. The model is in excellent agreement with recently published local...... metals, and thereby explain the pronounced differences in energetics in these two classes of metals. The model is discussed in the framework of the effective-medium theory where it is possible to find a functional form for the pair potential and relate the contribution associated with the fourth moment...

  16. Geothermal energy market potential in industrial processing

    Energy Technology Data Exchange (ETDEWEB)

    Schultz, R.J.; Hanny, J.A.; Knuth, W.H.

    1978-11-01

    Geothermal energy is currently being used for a number of industrial processes in countries throughout the world. Its application in the United States is mainly limited to space heating even though the temperature of the geothermal fluid is sufficient for process uses, and could be sold at attractive prices while maintaining a high return on investment. The temperature span for industrial use ranges from 40 to 275/sup 0/C, thus encompassing both the abundant low temperature and the less available high temperature resources. Hydrothermal fluids can be used either directly or indirectly dependent upon fluid quality and process needs. The barriers facing hydrothermal industrial process development are (a) the development infrastructure does not exist, (b) energy users are not aware of hydrothermal energy and its advantages, (c) federal incentives are limited, (d) resources are not fully defined.

  17. Potential evaluation of biomass-based energy sources for Turkey

    Directory of Open Access Journals (Sweden)

    Mustafa Ozcan

    2015-06-01

    Full Text Available Turkey has great potential with respect to renewable energy sources (RES and, among such sources, “biomass energy” is of particular importance. The purpose of this study is to determine the primary electrical energy potential obtainable from the biomass potential, according to different biomass source types. In this study, the biomass sources of municipal solid wastes, energy crops, animal manure and urban wastewater treatment sludge are evaluated. For each source, individual biogas and biomass energy potential calculations are made. Methods for energy conversion from wastes applicable to the conditions of Turkey, and technical and economic parameters are used. As a result of the calculations made, the total primary energy value of biogas obtainable from the examined sources is 188.21 TWh/year. The total primary energy value related to the potential of the evaluated biomass sources is 278.40 TWh/year.

  18. Energy potential in the food industry; Store energipotensialer i naeringsmiddelindustrien

    Energy Technology Data Exchange (ETDEWEB)

    Rosenberg, E; Risberg, T M; Mydske, H J; Helgerud, H E

    2007-07-01

    The food industry is one of the most power consuming industries (excluding the heavy industry) and has large potential for reducing the energy consumption. This report explains the most energy efficient measures and if the injunctions are followed

  19. Physico-chemical properties and energy potential of wood wastes ...

    African Journals Online (AJOL)

    Physico-chemical properties and energy potential of wood wastes from ... Journal Home > Vol 36, No 2 (2017) > ... The results are indications that the wood wastes are suitable as feedstock for renewable energy generation with little or no ...

  20. Estimating Roof Solar Energy Potential in the Downtown Area Using a GPU-Accelerated Solar Radiation Model and Airborne LiDAR Data

    OpenAIRE

    Yan Huang; Zuoqi Chen; Bin Wu; Liang Chen; Weiqing Mao; Feng Zhao; Jianping Wu; Junhan Wu; Bailang Yu

    2015-01-01

    Solar energy, as a clean and renewable resource is becoming increasingly important in the global context of climate change and energy crisis. Utilization of solar energy in urban areas is of great importance in urban energy planning, environmental conservation, and sustainable development. However, available spaces for solar panel installation in cities are quite limited except for building roofs. Furthermore, complex urban 3D morphology greatly affects sunlit patterns on building roofs, espe...

  1. Material and energy recovery in integrated waste management systems: the potential for energy recovery.

    Science.gov (United States)

    Consonni, Stefano; Viganò, Federico

    2011-01-01

    This article is part of a set of six coordinated papers reporting the main findings of a research project carried out by five Italian universities on "Material and energy recovery in Integrated Waste Management Systems (IWMS)". An overview of the project and a summary of the most relevant results can be found in the introductory article of the series. This paper describes the work related to the evaluation of mass and energy balances, which has consisted of three major efforts (i) development of a model for quantifying the energy content and the elemental compositions of the waste streams appearing in a IWMS; (ii) upgrade of an earlier model to predict the performances of Waste-to-Energy (WtE) plants; (iii) evaluation of mass and energy balances of all the scenarios and the recovery paths considered in the project. Results show that not only the amount of material available for energy recovery is significantly higher than the Unsorted Residual Waste (URW) left after Separate Collection (SC), because selection and recycling generate significant amounts of residues, but its heating value is higher than that of the original, gross waste. Therefore, the energy potential of what is left after recycling is always higher than the complement to 100% of the Source Separation Level (SSL). Also, increasing SSL has marginal effects on the potential for energy recovery: nearly doubling SSL (from 35% to 65%) reduces the energy potential only by one fourth. Consequently, even at high SSL energy recovery is a fundamental step of a sustainable waste management system. Variations of SSL do bring about variations of the composition, heating value and moisture content of the material fed to WtE plants, but these variations (i) are smaller than one can expect; (ii) have marginal effects on the performances of the WtE plant. These considerations suggest that the mere value of SSL is not a good indicator of the quality of the waste management system, nor of its energy and environmental

  2. Supersymmetry of Demkov-Ostrovsky effective potentials at zero energy

    CERN Document Server

    Rosu, H C; Wolf, K B; Obregón, O; Rosu, Haret C; Reyes, Marco A; Wolf, Kurt Bernardo; Obregon, Octavio

    1995-01-01

    We present a Natanzon-type supersymmetric analysis of the wave problem with Demkov-Ostrovsky (DO) spherically symmetric class of focusing potentials at zero energy. It is known that at zero binding energy there exists a degenerate ``bound" state for this class of potentials. Working at zero energy and in the so-called R_{0}=0 sector, we obtain the corresponding superpartner (fermionic) DO scattering potentials within the standard one-dimensional supersymmetric procedure.

  3. Available Potential Energy and the Maintenance of the General Circulation

    OpenAIRE

    Lorenz, Edward N.

    2011-01-01

    The available potential energy of the atmosphere may be defined as the difference between the total potential energy and the minimum total potential energy which could result from any adiabatic redistribution of mass. It vanishes if the density stratification is horizontal and statically stable everywhere, and is positive otherwise. It is measured approximately by a weighted vertical average of the horizontal variance of temperature. In magnitude it is generally about ten times the total kine...

  4. Potential evaluation of biomass-based energy sources for Turkey

    OpenAIRE

    Mustafa Ozcan; Semra Öztürk; Yuksel Oguz

    2015-01-01

    Turkey has great potential with respect to renewable energy sources (RES) and, among such sources, “biomass energy” is of particular importance. The purpose of this study is to determine the primary electrical energy potential obtainable from the biomass potential, according to different biomass source types. In this study, the biomass sources of municipal solid wastes, energy crops, animal manure and urban wastewater treatment sludge are evaluated. For each source, individual biogas and biom...

  5. Quantifying and Disaggregating Consumer Purchasing Behavior for Energy Systems Modeling

    Science.gov (United States)

    Consumer behaviors such as energy conservation, adoption of more efficient technologies, and fuel switching represent significant potential for greenhouse gas mitigation. Current efforts to model future energy outcomes have tended to use simplified economic assumptions ...

  6. Quantifying and Disaggregating Consumer Purchasing Behavior for Energy Systems Modeling

    Science.gov (United States)

    Consumer behaviors such as energy conservation, adoption of more efficient technologies, and fuel switching represent significant potential for greenhouse gas mitigation. Current efforts to model future energy outcomes have tended to use simplified economic assumptions ...

  7. Monte Carlo and theoretical calculations of the first four perturbation coefficients in the high temperature series expansion of the free energy for discrete and core-softened potential models

    Science.gov (United States)

    Zhou, Shiqi; Solana, J. R.

    2013-06-01

    The first four perturbation coefficients in the expansion of the Helmholtz free energy in power series of the inverse of the reduced temperature for a number of potential models with hard-sphere cores plus core-softened and discontinuous tails are obtained from Monte Carlo simulations. The potential models considered include square-well, double square-well, and square-shoulder plus square-well, with different potential parameters. These simulation data are used to evaluate the performance of a traditional macroscopic compressibility approximation (MCA) for the second order coefficient and a recent coupling parameter series expansion (CPSE) for the first four coefficients. Comprehensive comparison indicates the incapability of the MCA for the second order coefficient in most non-stringent situations, and significance of the CPSE in accurately calculating these four coefficients.

  8. Bandwidth Study on Energy Use and Potential Energy Savings Opportunities in U.S. Petroleum Refining

    Energy Technology Data Exchange (ETDEWEB)

    Sabine Brueske, Caroline Kramer, Aaron Fisher

    2015-06-01

    Energy bandwidth studies of U.S. manufacturing sectors can serve as foundational references in framing the range (or bandwidth) of potential energy savings opportunities. This bandwidth study examines energy consumption and potential energy savings opportunities in U.S. petroleum refining. The study relies on multiple sources to estimate the energy used in nine individual process areas, representing 68% of sector-wide energy consumption. Energy savings opportunities for individual processes are based on technologies currently in use or under development; these potential savings are then extrapolated to estimate sector-wide energy savings opportunity.

  9. Bandwidth Study on Energy Use and Potential Energy Saving Opportunities in U.S. Chemical Manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    Sabine Brueske, Caroline Kramer, Aaron Fisher

    2015-06-01

    Energy bandwidth studies of U.S. manufacturing sectors can serve as foundational references in framing the range (or bandwidth) of potential energy savings opportunities. This bandwidth study examines energy consumption and potential energy savings opportunities in U.S. chemical manufacturing. The study relies on multiple sources to estimate the energy used in the production of 74 individual chemicals, representing 57% of sector-wide energy consumption. Energy savings opportunities for individual chemicals and for 15 subsectors of chemicals manufacturing are based on technologies currently in use or under development; these potential savings are then extrapolated to estimate sector-wide energy savings opportunity.

  10. Statefinder Diagnostic for Born-Infeld Type Dark Energy Model

    Institute of Scientific and Technical Information of China (English)

    HUANG Zeng-Guang; LU Hui-Qing

    2008-01-01

    Using a new method called the statefinder diagnostics which can make one dark energy model differ from the others, we investigate the dynamics of Born-Infeld (B-I) type dark energy model. The evolution trajectory of B-I type dark energy with Mexican hat potential model with respect to e-folding time N is shown in the r (s) diagram, When the parameter of noncanonical kinetic energy term η→0 or kinetic energy ψ2→0, the B-I type dark energy (K-essence) model reduces to the quintessence model or the ACDM model corresponding to the statefinder pair {r, s}={1, 0} respectively. As a result, the evolution trajectory of our model in the r (s) diagram in Mexican hat potential is quite different from those of other dark energy models. The current values of parameters Ω,ψ and ω,ψ in this model meet the latest observations WMAP5 well.

  11. Estimating Solar Energy Potential in Buildings on a Global Level

    DEFF Research Database (Denmark)

    Petrichenko, Ksenia

    2015-01-01

    This chapter contributes to the debate around net-zero energy concept from a global perspective. By means of comprehensive modelling, it analyses how much global building energy consumption could be reduced through utilisation of building-integrated solar energy technologies and energy......-efficiency improvements. Valuable insights on the locations and building types, in which it is feasible to achieve a net-zero level of energy performance through solar energy utilisation, are presented in world maps....

  12. Potential Energy Sources Pose Mining Problem

    Science.gov (United States)

    Chemical and Engineering News, 1974

    1974-01-01

    Summarizes the discussions of a Division of Industrial and Engineering Chemistry symposium on solids handling for synthetic fuels production. Included is a description of technical difficulties with the use of coal seams and deposits of oil shale and oil sand as potential sources of fuel. (CC)

  13. Assessment of Wind Energy Potential in Golestan Province of Iran

    Directory of Open Access Journals (Sweden)

    Mehdi Hashemi-Tilehnoee

    2016-02-01

    Full Text Available Renewable energy sources are estimated to have a thriving future in many countries as well as Iran. The aim of this work is the evaluation of wind energy potentiality for the five counties of Golestan province in the northern region of Iran. A long term data source, consisting of  30 years in Gorgan, 22 years in Gonbade-e Qabus, 21 years in Maraveh Tappeh, 9 years in Aliabad, and 7 years in Bandar-e Turkaman of eight-hourly mean wind data, was adopted and analyzed. Mean wind power based on quantified data, Weibull distribution function, the relative percentage error (RPE and wind direction between obtaining values of wind power has been considered. According to these data, it was found that the numerical values of the shape parameter and scale parameter for Golestan varied a tight range. Annual values of ‘‘k’’ ranged from 2.7 to 4.7 where it is constant in different elevation because of better performance of this method in estimating wind energy potential, while annual values of ‘‘c’’ were in the range of 2.6 m/s in 10 m and 7.6 m/s in 40 m. Wind power densities have been estimated and relatively low for large wind turbines. The consequences indicate that in some months Maraveh Tappeh and Bandar-e Turkaman has best wind energy potential, as class 2, in order to establish some small wind turbine models for the sustainable development of Golestan province. Article History: Received Sept 13, 2015; Received in revised form Dec 27, 2015; Accepted January 17, 2016; Available online How to Cite This Article: Babayani, D., Khaleghi, M. and Hashemi-Tilehnoee, M. (2016 Assessment of Wind Energy Potential in Golestan Province of Iran. Int. Journal of Renewable Energy Development, 5(1, 25-31. http://dx.doi.org/10.14710/ijred.5.1.25-31 

  14. Raytracing simulations of coupled dark energy models

    CERN Document Server

    Pace, Francesco; Moscardini, Lauro; Bacon, David; Crittenden, Robert

    2014-01-01

    Dark matter and dark energy are usually assumed to be independent, coupling only gravitationally. An extension to this simple picture is to model dark energy as a scalar field which is directly coupled to the cold dark matter fluid. Such a non-trivial coupling in the dark sector leads to a fifth force and a time-dependent dark matter particle mass. In this work we examine the impact that dark energy-dark matter couplings have on weak lensing statistics by constructing realistic simulated weak-lensing maps using raytracing techniques through a suite of N-body cosmological simulations. We construct maps for an array of different lensing quantities, covering a range of scales from a few arcminutes to several degrees. The concordance $\\Lambda$CDM model is compared to different coupled dark energy models, described either by an exponential scalar field potential (standard coupled dark energy scenario) or by a SUGRA potential (bouncing model). We analyse several statistical quantities, in particular the power spect...

  15. Diabatic potential energy surfaces of H+ + CO

    Indian Academy of Sciences (India)

    F George D X; Sanjay Kumar

    2007-09-01

    Ab initio adiabatic and diabatic surfaces of the ground and the first excited electronic states have been computed for the H+ + CO system for the collinear ( = 0°) and the perpendicular ( = 90°) geometries employing the multi-reference configuration interaction method and Dunning's -VTZ basis set. Other properties such as mixing angle before coupling potential and before coupling matrix elements have also been obtained in order to provide an understanding of the coupling dynamics of inelastic and charge transfer process.

  16. Holographic dark-energy models

    Science.gov (United States)

    Del Campo, Sergio; Fabris, Júlio. C.; Herrera, Ramón; Zimdahl, Winfried

    2011-06-01

    Different holographic dark-energy models are studied from a unifying point of view. We compare models for which the Hubble scale, the future event horizon or a quantity proportional to the Ricci scale are taken as the infrared cutoff length. We demonstrate that the mere definition of the holographic dark-energy density generally implies an interaction with the dark-matter component. We discuss the relation between the equation-of-state parameter and the energy density ratio of both components for each of the choices, as well as the possibility of noninteracting and scaling solutions. Parameter estimations for all three cutoff options are performed with the help of a Bayesian statistical analysis, using data from supernovae type Ia and the history of the Hubble parameter. The ΛCDM model is the clear winner of the analysis. According to the Bayesian information criterion (BIC), all holographic models should be considered as ruled out, since the difference ΔBIC to the corresponding ΛCDM value is >10. According to the Akaike information criterion (AIC), however, we find ΔAIC<2 for models with Hubble-scale and Ricci-scale cutoffs, indicating, that they may still be competitive. As we show for the example of the Ricci-scale case, also the use of certain priors, reducing the number of free parameters to that of the ΛCDM model, may result in a competitive holographic model.

  17. Potential energy surfaces and reaction dynamics of polyatomic molecules

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Yan-Tyng.

    1991-11-01

    A simple empirical valence bond (EVB) model approach is suggested for constructing global potential energy surfaces for reactions of polyatomic molecular systems. This approach produces smooth and continuous potential surfaces which can be directly utilized in a dynamical study. Two types of reactions are of special interest, the unimolecular dissociation and the unimolecular isomerization. For the first type, the molecular dissociation dynamics of formaldehyde on the ground electronic surface is investigated through classical trajectory calculations on EVB surfaces. The product state distributions and vector correlations obtained from this study suggest very similar behaviors seen in the experiments. The intramolecular hydrogen atom transfer in the formic acid dimer is an example of the isomerization reaction. High level ab initio quantum chemistry calculations are performed to obtain optimized equilibrium and transition state dimer geometries and also the harmonic frequencies.

  18. A hierarchy of potential energy surfaces constructed from energies and energy derivatives calculated on grids

    Science.gov (United States)

    Matito, Eduard; Toffoli, Daniele; Christiansen, Ove

    2009-04-01

    In this work we develop and test a methodology for the generation of Born-Oppenheimer potential energy surfaces (PES) for use in vibrational structure calculations. The method relies on the widely used restricted-mode-coupling expansion of the fully coupled potential surface where only up to n or less vibrational coordinates are coupled in the potential. Low-order derivatives of the energy are then used to extrapolate the higher mode-coupling potential terms; derivative information is thus used in a convenient way for the evaluation of higher mode couplings avoiding their explicit calculation on multidimensional grids. The formulation, which is a variant of the popular modified Shepard interpolation, is general for any extrapolation of (n +p)-mode-coupling terms from n-mode couplings and can be applied to the energy or any other molecular property surface for which derivative information is available. The method depends only on analytical parameter-free weight functions that satisfy important limiting conditions and control the contribution from each direction of extrapolation. The procedure has been applied on a representative set of 13 molecules, and its accuracy has been tested using only gradients and using both gradients and Hessians. The results provide evidence for the importance of higher mode couplings and illustrate the cost efficiency of the proposed approach.

  19. Wind energy potential in Aden-Yemen

    Energy Technology Data Exchange (ETDEWEB)

    Algifri, A.H. [University of Aden (Republic of Yemen). Faculty of Engineering

    1998-02-01

    In this article a number of years data on wind speed in Aden has been studied and presented. A statistical analysis was carried out from which the annual wind speed was found to be 4.5 m/s and most of the time the wind speed is in the range of 3.5-7.5 m/s. The wind speed distributions were represented by Weibull and Rayleigh distributions. It was found that the Rayleigh distribution is suitable to represent the actual probability of wind speed data for Aden. The wind speed data showed that the maximum monthly wind speed occurs in the month of February with the maximum in the month of June. It is concluded that Aden can be explored for wind energy applications. (author)

  20. Assessment of Global Wind Energy Resource Utilization Potential

    Science.gov (United States)

    Ma, M.; He, B.; Guan, Y.; Zhang, H.; Song, S.

    2017-09-01

    Development of wind energy resource (WER) is a key to deal with climate change and energy structure adjustment. A crucial issue is to obtain the distribution and variability of WER, and mine the suitable location to exploit it. In this paper, a multicriteria evaluation (MCE) model is constructed by integrating resource richness and stability, utilization value and trend of resource, natural environment with weights. The global resource richness is assessed through wind power density (WPD) and multi-level wind speed. The utilizable value of resource is assessed by the frequency of effective wind. The resource stability is assessed by the coefficient of variation of WPD and the frequency of prevailing wind direction. Regression slope of long time series WPD is used to assess the trend of WER. All of the resource evaluation indicators are derived from the atmospheric reanalysis data ERA-Interim with spatial resolution 0.125°. The natural environment factors mainly refer to slope and land-use suitability, which are derived from multi-resolution terrain elevation data 2010 (GMTED 2010) and GlobalCover2009. Besides, the global WER utilization potential map is produced, which shows most high potential regions are located in north of Africa. Additionally, by verifying that 22.22 % and 48.8 9% operational wind farms fall on medium-high and high potential regions respectively, the result can provide a basis for the macroscopic siting of wind farm.

  1. Microscopically derived potential energy surfaces from mostly structural considerations

    Energy Technology Data Exchange (ETDEWEB)

    Ermamatov, M.J. [Instituto de Física, Universidade Federal Fluminense, 24210-340, Niterói, Rio de Janeiro (Brazil); Institute of Nuclear Physics, Ulughbek, Tashkent 100214 (Uzbekistan); Hess, Peter O., E-mail: hess@nucleares.unam.mx [Instituto de Ciencias Nucleares, UNAM, Circuito Exterior, C.U., A.P. 70-543, 04510, Mexico D.F. (Mexico)

    2016-08-15

    A simple procedure to estimate the quadrupole Potential-Energy-Surface (PES) is presented, using mainly structural information, namely the content of the shell model space and the Pauli exclusion principle. Further microscopic properties are implicitly contained through the use of results from the Möller and Nix tables or experimental information. A mapping to the geometric potential is performed yielding the PES. The General Collective Model is used in order to obtain an estimate on the spectrum and quadrupole transitions, adjusting only the mass parameter. First, we test the conjecture on known nuclei, deriving the PES and compare them to known data. We will see that the PES approximates very well the structure expected. Having acquired a certain confidence, we predict the PES of several chain of isotopes of heavy and super-heavy nuclei and at the end we investigate the structure of nuclei in the supposed island of stability. One of the main points to show is that simple assumptions can provide already important information on the structure of nuclei outside known regions and that spectra and electromagnetic transitions can be estimated without using involved calculations and assumptions. The procedure does not allow to calculate binding energies. The method presented can be viewed as a starting point for further improvements.

  2. Offshore wind energy potential in China

    DEFF Research Database (Denmark)

    Hong, Lixuan; Möller, Bernd

    2011-01-01

    and economic costs. However, the influence of tropical cyclone risks on these regions and detailed assessments at regional or local scale are worth of further discussions. Nevertheless, the models and results provide a foundation for a more comprehensive regional planning framework that would address...

  3. Geothermal energy potential in the San Luis Valley, Colorado

    Energy Technology Data Exchange (ETDEWEB)

    Coe, B.A.

    1980-01-01

    The background of the area itself is investigated considering the geography, population, economy, attitudes of residents, and energy demands of the area. The requirements for geothermal energy development are considered, including socio-economic, institutional, and environmental conditions as well as some technical aspects. The current, proposed, and potential geothermal energy developments are described. The summary, conclusions, and methodology are included. (MHR)

  4. Energy saving potential of emerging technologies in milk powder production

    NARCIS (Netherlands)

    Moejes, S.N.; Boxtel, van A.J.B.

    2017-01-01

    Background

    The food industry has a large potential for energy reduction which, with an eye on the future, has to be exploited. Milk powder production consists of many thermal processes and is responsible for 15% of the total energy use in the dairy industry. A reduction in energy consumptio

  5. Intersections of potential energy surfaces of short-lived states: the complex analogue of conical intersections.

    Science.gov (United States)

    Feuerbacher, Sven; Sommerfeld, Thomas; Cederbaum, Lorenz S

    2004-02-15

    Whereas conical intersections between potential energy surfaces of bound states are well known, the interaction of short-lived states has been investigated only rarely. Here, we present several systematically constructed model Hamiltonians to study the topology of intersecting complex potential energy surfaces describing short-lived states: We find the general phenomenon of doubly intersecting complex energy surfaces, i.e., there are two points instead of one as in the case of bound states where the potential energy surfaces coalesce. In addition, seams of intersections of the respective real and imaginary parts of the potential energy surfaces emanate from these two points. Using the Sigma* and Pi* resonance states of the chloroethene anion as a practical example, we demonstrate that our complete linear model Hamiltonian is able to reproduce all phenomena found in explicitly calculated ab initio complex potential energy surfaces.

  6. Energy technologies and energy efficiency in economic modelling

    DEFF Research Database (Denmark)

    Klinge Jacobsen, Henrik

    1998-01-01

    This paper discusses different approaches to incorporating energy technologies and technological development in energy-economic models. Technological development is a very important issue in long-term energy demand projections and in environmental analyses. Different assumptions on technological ...... of renewable energy and especially wind power will increase the rate of efficiency improvement. A technologically based model in this case indirectly makes the energy efficiency endogenous in the aggregate energy-economy model.......This paper discusses different approaches to incorporating energy technologies and technological development in energy-economic models. Technological development is a very important issue in long-term energy demand projections and in environmental analyses. Different assumptions on technological...... development are one of the main causes for the very diverging results which have been obtained using bottom-up and top-down models for analysing the costs of greenhouse gas mitigation. One of the objectives for studies comparing model results have been to create comparable model assumptions regarding...

  7. Building Energy Model Development for Retrofit Homes

    Energy Technology Data Exchange (ETDEWEB)

    Chasar, David; McIlvaine, Janet; Blanchard, Jeremy; Widder, Sarah H.; Baechler, Michael C.

    2012-09-30

    Based on previous research conducted by Pacific Northwest National Laboratory and Florida Solar Energy Center providing technical assistance to implement 22 deep energy retrofits across the nation, 6 homes were selected in Florida and Texas for detailed post-retrofit energy modeling to assess realized energy savings (Chandra et al, 2012). However, assessing realized savings can be difficult for some homes where pre-retrofit occupancy and energy performance are unknown. Initially, savings had been estimated using a HERS Index comparison for these homes. However, this does not account for confounding factors such as occupancy and weather. This research addresses a method to more reliably assess energy savings achieved in deep energy retrofits for which pre-retrofit utility bills or occupancy information in not available. A metered home, Riverdale, was selected as a test case for development of a modeling procedure to account occupancy and weather factors, potentially creating more accurate estimates of energy savings. This “true up” procedure was developed using Energy Gauge USA software and post-retrofit homeowner information and utility bills. The 12 step process adjusts the post-retrofit modeling results to correlate with post-retrofit utility bills and known occupancy information. The “trued” post retrofit model is then used to estimate pre-retrofit energy consumption by changing the building efficiency characteristics to reflect the pre-retrofit condition, but keeping all weather and occupancy-related factors the same. This creates a pre-retrofit model that is more comparable to the post-retrofit energy use profile and can improve energy savings estimates. For this test case, a home for which pre- and post- retrofit utility bills were available was selected for comparison and assessment of the accuracy of the “true up” procedure. Based on the current method, this procedure is quite time intensive. However, streamlined processing spreadsheets or

  8. Morphing ab initio potential energy curve of beryllium monohydride

    Science.gov (United States)

    Špirko, Vladimír

    2016-12-01

    Effective (mass-dependent) potential energy curves of the ground electronic states of 9BeH, 9BeD, and 9BeT are constructed by morphing a very accurate MR-ACPF ab initio potential of Koput (2011) within the framework of the reduced potential energy curve approach of Jenč (1983). The morphing is performed by fitting the RPC parameters to available experimental ro-vibrational data. The resulting potential energy curves provide a fairly quantitative reproduction of the fitted data. This allows for a reliable prediction of the so-far unobserved molecular states in terms of only a small number of fitting parameters.

  9. The potential role of hydrogen energy in India and Western Europe

    NARCIS (Netherlands)

    van Ruijven, B.J.; Lakshmikanth, H.D.; van Vuuren, D.P.; de Vries, B.

    2008-01-01

    We used the TIMER energy model to explore the potential role of hydrogen in the energy systems of India and Western Europe, looking at the impacts on its main incentives: climate policy, energy security and urban air pollution. We found that hydrogen will not play a major role in both regions withou

  10. CONNECTION BETWEEN THE POTENTIAL WIND ENERGY AND THE WINDY DAYS

    Directory of Open Access Journals (Sweden)

    KÁROLY TAR

    2008-06-01

    Full Text Available Preliminary wind climate information are required for the selection of the sites of energetic wind measurements. Optimal locations of wind energy projects, where the amount of utilizable wind energy can be forecasted with a good approach, can be determined using GIS and statistical methods. Anyhow, it is necessary to elaborate methods what make posible to gain data for the wind potential of a given location on the base of measured data. Monthly number of windy days can be such predictor if its basic statistical parameters and its connection to the monthly mean wind power can be determined. This latter one can be substituted by the area under the curve of the function fitted to thehourly averages of the cubes of the wind speeds. A regression modell is fitted to the monthly number of windy days and areas under the curve, on the base of time series of 7 Hungarian weather stations and the error of the modell is determined. On this base, the modell is extrapolated to a 35 years long period. The area under the curve proportional to the monthly mean wind power calculated on the base of the monthly number of windy days show a significant decreasing trend in 4 Hungarian weather stations.

  11. Regional Differences in China's Energy Efficiency and Conservation Potentials

    Institute of Scientific and Technical Information of China (English)

    Shi Dan

    2007-01-01

    This paper investigates the maximum energy efficiency level and the energy saving potentials in each region in China that can be practically attained at current economic and technological development levels. Most of the nation's energy efficient provinces are found along the coast of southeast China, while most of its least energy efficient provinces are in the hinterland that is rich in coal resources, and which depends heavily on coal consumption. China's low efficiency in energy resource allocation stems from its secondary industry, which is handicapped by the lowest energy efficiency and the most striking regional differentials. 4comparison of the factors affecting the energy efficiency shows that the provinces being compared in this study differ tremendously in energy consumption structure, technological level of the secondary industry, and abundance of energy resources, and that the other factors are only adequate, rather than necessary, conditions. It is imperative to rectify the behaviors of provinces in balancing local energy allocation, to channel energy resources to energy efficient provinces, and to improve the national energy efficiency as a whole. When taking energy-saving steps, provinces must take into full consideration both the national and local factors that affect energy efficiency. Furthermore, it is unrealistic for China to set a unified energy saving goal for different provinces.

  12. Potential Energy Surfaces of Nitrogen Dioxide for the Ground State

    Institute of Scientific and Technical Information of China (English)

    SHAO Ju-Xiang; ZHU Zheng-He; CHENG Xin-Lu; YANG Xiang-Dong

    2007-01-01

    The potential energy function of nitrogen dioxide with the C2v symmetry in the ground state is represented using the simplified Sorbie-Murrell many-body expansion function in terms of the symmetry of NO2. Using the potential energy function, some potential energy surfaces of NO2(C2v, X2A1), such as the bond stretching contour plot for a fixed equilibrium geometry angle θ and contour for O moving around N-O (R1), in which R1 is fixed at the equilibrium bond length, are depicted. The potential energy surfaces are analysed. Moreover, the equilibrium parameters for NO2 with the C2v, Cs and D8h symmetries, such as equilibrium geometry structures and energies, are calculated by the ab initio (CBS-Q) method.

  13. New Bound State Energies for Spherical Quantum Dots in Presence of a Confining Potential Model at Nano and Plank’s Scales

    OpenAIRE

    Abdelmadjid Maireche

    2016-01-01

    In present work, the exact analytical bound-state solutions of modified Schrödinger equation with Modified central potential consisting of a Cornellmodified plus pseudoharmonic harmonic potential (MCMpH) have been presented using both Boopp’s shift method and standard perturbation theory, we have also constructed the corresponding noncommutative Hamiltonian which containing two new terms, the first one is modified Zeeman effect and the second is new spin-orbital interaction. The theoretical r...

  14. Biomass energy: the scale of the potential resource.

    Science.gov (United States)

    Field, Christopher B; Campbell, J Elliott; Lobell, David B

    2008-02-01

    Increased production of biomass for energy has the potential to offset substantial use of fossil fuels, but it also has the potential to threaten conservation areas, pollute water resources and decrease food security. The net effect of biomass energy agriculture on climate could be either cooling or warming, depending on the crop, the technology for converting biomass into useable energy, and the difference in carbon stocks and reflectance of solar radiation between the biomass crop and the pre-existing vegetation. The area with the greatest potential for yielding biomass energy that reduces net warming and avoids competition with food production is land that was previously used for agriculture or pasture but that has been abandoned and not converted to forest or urban areas. At the global scale, potential above-ground plant growth on these abandoned lands has an energy content representing approximately 5% of world primary energy consumption in 2006. The global potential for biomass energy production is large in absolute terms, but it is not enough to replace more than a few percent of current fossil fuel usage. Increasing biomass energy production beyond this level would probably reduce food security and exacerbate forcing of climate change.

  15. Energy modeling towards low carbon development of Beijing in 2030

    DEFF Research Database (Denmark)

    Zhao, Guangling; Chen, Sha; Guerrero, Josep M.

    2017-01-01

    renewable energy and low carbon development for the city of Beijing. The analysis of energy system modeling is organized in two steps to explore the potential renewable energy alternative in Beijing. Firstly, a reference energy system of Beijing is created based on the available data in 2014. The Energy......PLAN, an energy system analysis tool, is chosen to develop the reference energy model. Secondly, this reference model is used to investigate the alternative energy system for integrating renewable energies. Three scenarios are developed towards the energy system of Beijing in 2030, which are: (i) reference...... scenario 2030, (ii) BAU (business as usual) scenario 2030 and (iii) RES (renewable energies) scenario 2030. The results shows that the share of renewables can increase to 100% of electricity and heat production in the RE scenario. The primary fuel consumption is reduced to 155.9 TWh, which is 72 % of fuel...

  16. RESRO: A spatio-temporal model to optimise regional energy systems emphasising renewable energies

    OpenAIRE

    2012-01-01

    RESRO (Reference Energy System Regional Optimization) optimises the simultaneous fulfilment of the heat and power demand in regional energy systems. It is a mixed-integer program realised in the modelling language GAMS. The model handles information on geographically disaggregated data describing heat demand and renewable energy potentials (e.g. biomass, solar energy, ambient heat). Power demand is handled spatially aggregated in an hourly time resolution within 8 type days. The major idea is...

  17. Renewable energy potential from biomass residues in Egypt

    Energy Technology Data Exchange (ETDEWEB)

    Said, N.; Zamorano, M. [Civil Engineering Dept., Univ. of Granada, Campus de Fuentenueva, Granada (Spain); El-Shatoury, S.A. [Botany Dept., Faculty of Sciences, Suez Canal Univ., Ismailia (Egypt)

    2012-11-01

    Egypt has been one of the developing countries following successful programs for the development of renewable energy resources, with special emphasis on solar, wind and biomass. Utilization of biomass as a source of energy is important from energetic as well as environmental viewpoint. Furthermore, Egypt produces millions of biomass waste every year causing pollution and health problems. So, the incorporation of biomass with other renewable energy will increase the impact of solving energy and environmental problem. There is a good potential for the utilization of biomass energy resources in Egypt. Four main types of biomass energy sources are included in this study: agricultural residues, municipal solid wastes, animal wastes and sewage sludge. Analysis of the potential biomass resource quantity and its theoretical energy content has been computed according to literature review. The agriculture crop residue represents the main source of biomass waste with a high considerable amount of the theoretical potential energy in Egypt. Rice straw is considered one of the most important of such residue due to its high amount and its produced energy through different conversion techniques represent a suitable candidate for crop energy production in Egypt.

  18. Defining The Energy Saving Potential of Architectural Design

    DEFF Research Database (Denmark)

    Naboni, Emanuele; Malcangi, Antonio; Zhang, Yi

    2015-01-01

    Designers, in response to codes or voluntary " green building " programs, are increasingly concerned with building energy demand reduction, but they are not fully aware of the energy saving potential of architectural design. According to literature, building form, construction and material choices...... on sustainable design: " Design With Climate " by Olgyay (1963), which discussed strategies for climate-adapted architecture, and Lechner´s " Heating, Cooling and Lighting " (1991), on how to reduce building energy needs by as much as 60 – 80 percent with proper architectural design decisions. Both books used...... behaviour. The research shows the best solution for each of the climates and compares them with Olgyay´s findings. Finally, for each climate the energy saving potential is defined and then compared to Lechner's conclusions. Defining The Energy Saving Potential of Architectural Design (PDF Download Available...

  19. Potential energy curves for neutral and multiply charged carbon monoxide

    Indian Academy of Sciences (India)

    Pradeep Kumar; N Sathyamurthy

    2010-01-01

    Potential energy curves of various electronic states of CO+ (0 ≤ ≤ 6) are generated at MRCI/CASSCF level using cc-pvQZ basis set and the results are compared with available experimental and theoretical data.

  20. Evaluating energy efficiency policies with energy-economy models

    NARCIS (Netherlands)

    Mundaca, L.; Neij, L.; Worrell, E.; McNeil, M.

    2010-01-01

    The growing complexities of energy systems, environmental problems, and technology markets are driving and testing most energy-economy models to their limits. To further advance bottom-up models from a multidisciplinary energy efficiency policy evaluation perspective, we review and critically analyz

  1. Possible explanation of the atmospheric kinetic and potential energy spectra.

    Science.gov (United States)

    Vallgren, Andreas; Deusebio, Enrico; Lindborg, Erik

    2011-12-23

    We hypothesize that the observed wave number spectra of kinetic and potential energy in the atmosphere can be explained by assuming that there are two related cascade processes emanating from the same large-scale energy source, a downscale cascade of potential enstrophy, giving rise to the k(-3) spectrum at synoptic scales and a downscale energy cascade giving rise to the k(-5/3) spectrum at mesoscales. The amount of energy which is going into the downscale energy cascade is determined by the rate of system rotation, with negligible energy going downscale in the limit of very fast rotation. We present a set of simulations of a system with strong rotation and stratification, supporting these hypotheses and showing good agreement with observations.

  2. Modeling Malaysia's Energy System: Some Preliminary Results

    OpenAIRE

    Ahmad M. Yusof

    2011-01-01

    Problem statement: The current dynamic and fragile world energy environment necessitates the development of new energy model that solely caters to analyze Malaysias energy scenarios. Approach: The model is a network flow model that traces the flow of energy carriers from its sources (import and mining) through some conversion and transformation processes for the production of energy products to final destinations (energy demand sectors). The integration to the economic sectors is done exogene...

  3. Evaluating Energy Efficiency Policies with Energy-Economy Models

    Energy Technology Data Exchange (ETDEWEB)

    Mundaca, Luis; Neij, Lena; Worrell, Ernst; McNeil, Michael A.

    2010-08-01

    The growing complexities of energy systems, environmental problems and technology markets are driving and testing most energy-economy models to their limits. To further advance bottom-up models from a multidisciplinary energy efficiency policy evaluation perspective, we review and critically analyse bottom-up energy-economy models and corresponding evaluation studies on energy efficiency policies to induce technological change. We use the household sector as a case study. Our analysis focuses on decision frameworks for technology choice, type of evaluation being carried out, treatment of market and behavioural failures, evaluated policy instruments, and key determinants used to mimic policy instruments. Although the review confirms criticism related to energy-economy models (e.g. unrealistic representation of decision-making by consumers when choosing technologies), they provide valuable guidance for policy evaluation related to energy efficiency. Different areas to further advance models remain open, particularly related to modelling issues, techno-economic and environmental aspects, behavioural determinants, and policy considerations.

  4. Teaching Potential Energy Functions and Stability with Slap Bracelets

    Science.gov (United States)

    Van Hook, Stephen J.

    2005-10-01

    The slap bracelet, an inexpensive child's toy, makes it easy to engage students in hands-on exploration of potential energy curves as well as of stable, unstable, and meta-stable states. Rather than just observing the teacher performing a demonstration, the students can manipulate the equipment themselves and make their own observations, which are then pooled to focus a class discussion on potential energy functions and stability.

  5. On Conversions between Potential and Kinetic Energy in the Atmospher

    OpenAIRE

    White, Robert M.; Saltzman, Barry

    2011-01-01

    From a consideration of the large-scale horizontal variations of individual pressure change and 500 mb temperature in a mid-latitude sector of the Northern Hemisphere, computations are made of the required mean conversion of potential energy into the kinetic energy of the horizontal wind systems. The order of magnitude of the estimate obtained is in agreement with that obtained by Brunt from considerations of the frictional dissipation of kinetic energy. In addition, the role of organized ove...

  6. Solar and wind energy potential and utilization in Pakistan

    Energy Technology Data Exchange (ETDEWEB)

    Raja, I.A. (Balochistan Univ., Quetta (Pakistan). Dept. of Physics); Abro, R.S. (Sheffield Univ. (United Kingdom). School of Architecture Studies)

    1994-08-01

    This paper identifies the potentials of solar and wind energy. The prime sites for wind are coastal area, arid zone and hill terrains. Solar energy is abundant over most parts of the country, the maximum being received over Quetta valley. (author)

  7. Gravitational potential as a source of earthquake energy

    Science.gov (United States)

    Barrows, L.; Langer, C.J.

    1981-01-01

    Some degree of tectonic stress within the earth originates from gravity acting upon density structures. The work performed by this "gravitational tectonics stress" must have formerly existed as gravitational potential energy contained in the stress-causing density structure. According to the elastic rebound theory (Reid, 1910), the energy of earthquakes comes from an elastic strain field built up by fairly continuous elastic deformation in the period between events. For earthquakes resulting from gravitational tectonic stress, the elastic rebound theory requires the transfer of energy from the gravitational potential of the density structures into an elastic strain field prior to the event. An alternate theory involves partial gravitational collapse of the stress-causing density structures. The earthquake energy comes directly from a net decrease in gravitational potential energy. The gravitational potential energy released at the time of the earthquake is split between the energy released by the earthquake, including work done in the fault zone and an increase in stored elastic strain energy. The stress associated with this elastic strain field should oppose further fault slip. ?? 1981.

  8. Geospatial Analysis of Renewable Energy Technical Potential on Tribal Lands

    Energy Technology Data Exchange (ETDEWEB)

    Doris, E.; Lopez, A.; Beckley, D.

    2013-02-01

    This technical report uses an established geospatial methodology to estimate the technical potential for renewable energy on tribal lands for the purpose of allowing Tribes to prioritize the development of renewable energy resources either for community scale on-tribal land use or for revenue generating electricity sales.

  9. Modelling energy consumption in a manufacturing plant using productivity KPIs

    Energy Technology Data Exchange (ETDEWEB)

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

    2009-07-01

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

  10. Conversion potential energy and its application to thermodynamic optimization

    Institute of Scientific and Technical Information of China (English)

    WU Jing; GUO ZengYuan

    2012-01-01

    In general,heat transfers can be classified into two categories according to the purposes of object heating or cooling and the heat to work conversion.Recently,a new physical quantity,entransy (or potential energy),was proposed to describe the ability of heat transfer with the former purpose.This paper addresses the concept of potential energy in terms of the heat transfer processes for the latter purpose,named the conversion potential energy.The physical meaning of this newly introduced concept is the potential energy for the heat to work conversion stored in the equivalent mass of heat (thermomass) derived on the basis of the Einstein's special theory of relativity.The dissipation of conversion potential energy occurs during the real irreversible heat to work conversion processes as a measure of the conversion irreversibility.Finally,a heat to work conversion problem of a heat exchanger group is provided to show that the minimum conversion potential energy dissipation rate can be used as an optimization criterion for the heat transfer performance with the purpose of the heat to work conversion.

  11. Modelling distributed energy resources in energy service networks

    CERN Document Server

    Acha, Salvador

    2013-01-01

    Focuses on modelling two key infrastructures (natural gas and electrical) in urban energy systems with embedded technologies (cogeneration and electric vehicles) to optimise the operation of natural gas and electrical infrastructures under the presence of distributed energy resources

  12. Separable representation of energy-dependent optical potentials

    Science.gov (United States)

    Hlophe, L.; Elster, Ch.

    2016-03-01

    Background: One important ingredient for many applications of nuclear physics to astrophysics, nuclear energy, and stockpile stewardship are cross sections for reactions of neutrons with rare isotopes. Since direct measurements are often not feasible, indirect methods, e.g., (d ,p ) reactions, should be used. Those (d ,p ) reactions may be viewed as three-body reactions and described with Faddeev techniques. Purpose: Faddeev equations in momentum space have a long tradition of utilizing separable interactions in order to arrive at sets of coupled integral equations in one variable. Optical potentials representing the effective interactions in the neutron (proton) nucleus subsystem are usually non-Hermitian as well as energy dependent. Potential matrix elements as well as transition matrix elements calculated with them must fulfill the reciprocity theorem. The purpose of this paper is to introduce a separable, energy-dependent representation of complex, energy-dependent optical potentials that fulfill reciprocity exactly. Methods: Momentum space Lippmann-Schwinger integral equations are solved with standard techniques to obtain the form factors for the separable representation. Results: Starting from a separable, energy-independent representation of global optical potentials based on a generalization of the Ernst-Shakin-Thaler (EST) scheme, a further generalization is needed to take into account the energy dependence. Applications to n +48Ca ,n +208Pb , and p +208Pb are investigated for energies from 0 to 50 MeV with special emphasis on fulfilling reciprocity. Conclusions: We find that the energy-dependent separable representation of complex, energy-dependent phenomenological optical potentials fulfills reciprocity exactly. In addition, taking into account the explicit energy dependence slightly improves the description of the S matrix elements.

  13. Solar energy in California industry - Applications, characteristics and potential

    Science.gov (United States)

    Barbieri, R. H.; Pivirotto, D. S.

    1978-01-01

    Results of a survey to determine the potential applicability of solar thermal energy to industrial processes in California are presented. It is found that if the heat for all industrial processes at temperatures below 212 F were supplied by solar energy, total state energy consumption could be reduced by 100 trillion Btus (2%), while the use of solar energy in processes between 212 and 350 F could displace 500 trillion Btus. The issues and problems with which solar energy must contend are illustrated by a description of fluid milk processing operations. Solar energy application is found to be technically feasible for processes with thermal energy requirements below 212 F, with design, and degree of technical, economic and management feasibility being site specific. It is recommended that the state provide support for federal and industrial research, development and demonstration programs in order to stimulate acceptance of solar process heat application by industry.

  14. Solar energy in California industry - Applications, characteristics and potential

    Science.gov (United States)

    Barbieri, R. H.; Pivirotto, D. S.

    1978-01-01

    Results of a survey to determine the potential applicability of solar thermal energy to industrial processes in California are presented. It is found that if the heat for all industrial processes at temperatures below 212 F were supplied by solar energy, total state energy consumption could be reduced by 100 trillion Btus (2%), while the use of solar energy in processes between 212 and 350 F could displace 500 trillion Btus. The issues and problems with which solar energy must contend are illustrated by a description of fluid milk processing operations. Solar energy application is found to be technically feasible for processes with thermal energy requirements below 212 F, with design, and degree of technical, economic and management feasibility being site specific. It is recommended that the state provide support for federal and industrial research, development and demonstration programs in order to stimulate acceptance of solar process heat application by industry.

  15. Modeling energy transport in nanostructures

    Science.gov (United States)

    Pattamatta, Arvind

    Heat transfer in nanostructures differ significantly from that in the bulk materials since the characteristic length scales associated with heat carriers, i.e., the mean free path and the wavelength, are comparable to the characteristic length of the nanostructures. Nanostructure materials hold the promise of novel phenomena, properties, and functions in the areas of thermal management and energy conversion. Example of thermal management in micro/nano electronic devices is the use of efficient nanostructured materials to alleviate 'hot spots' in integrated circuits. Examples in the manipulation of heat flow and energy conversion include nanostructures for thermoelectric energy conversion, thermophotovoltaic power generation, and data storage. One of the major challenges in Metal-Oxide Field Effect Transistor (MOSFET) devices is to study the 'hot spot' generation by accurately modeling the carrier-optical phonon-acoustic phonon interactions. Prediction of hotspot temperature and position in MOSFET devices is necessary for improving thermal design and reliability of micro/nano electronic devices. Thermoelectric properties are among the properties that may drastically change at nanoscale. The efficiency of thermoelectric energy conversion in a material is measured by a non-dimensional figure of merit (ZT) defined as, ZT = sigmaS2T/k where sigma is the electrical conductivity, S is the Seebeck coefficient, T is the temperature, and k is the thermal conductivity. During the last decade, advances have been made in increasing ZT using nanostructures. Three important topics are studied with respect to energy transport in nanostructure materials for micro/nano electronic and thermoelectric applications; (1) the role of nanocomposites in improving the thermal efficiency of thermoelectric devices, (2) the interfacial thermal resistance for the semiconductor/metal contacts in thermoelectric devices and for metallic interconnects in micro/nano electronic devices, (3) the

  16. Metallic bionanocatalysts: potential applications as green catalysts and energy materials.

    Science.gov (United States)

    Macaskie, Lynne E; Mikheenko, Iryna P; Omajai, Jacob B; Stephen, Alan J; Wood, Joseph

    2017-08-22

    Microbially generated or supported nanocatalysts have potential applications in green chemistry and environmental application. However, precious (and base) metals biorefined from wastes may be useful for making cheap, low-grade catalysts for clean energy production. The concept of bionanomaterials for energy applications is reviewed with respect to potential fuel cell applications, bio-catalytic upgrading of oils and manufacturing 'drop-in fuel' precursors. Cheap, effective biomaterials would facilitate progress towards dual development goals of sustainable consumption and production patterns and help to ensure access to affordable, reliable, sustainable and modern energy. © 2017 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  17. Investigating Energy-Saving Potentials in the Cloud

    Directory of Open Access Journals (Sweden)

    Da-Sheng Lee

    2014-02-01

    Full Text Available Collecting webpage messages can serve as a sensor for investigating the energy-saving potential of buildings. Focusing on stores, a cloud sensor system is developed to collect data and determine their energy-saving potential. The owner of a store under investigation must register online, report the store address, area, and the customer ID number on the electric meter. The cloud sensor system automatically surveys the energy usage records by connecting to the power company website and calculating the energy use index (EUI of the store. Other data includes the chain store check, company capital, location price, and the influence of weather conditions on the store; even the exposure frequency of store under investigation may impact the energy usage collected online. After collecting data from numerous stores, a multi-dimensional data array is constructed to determine energy-saving potential by identifying stores with similarity conditions. Similarity conditions refer to analyzed results that indicate that two stores have similar capital, business scale, weather conditions, and exposure frequency on web. Calculating the EUI difference or pure technical efficiency of stores, the energy-saving potential is determined. In this study, a real case study is performed. An 8-dimensional (8D data array is constructed by surveying web data related to 67 stores. Then, this study investigated the savings potential of the 33 stores, using a site visit, and employed the cloud sensor system to determine the saving potential. The case study results show good agreement between the data obtained by the site visit and the cloud investigation, with errors within 4.17%. Among 33 the samples, eight stores have low saving potentials of less than 5%. The developed sensor on the cloud successfully identifies them as having low saving potential and avoids wasting money on the site visit.

  18. Sustainable energy. Economic growth for the Netherlands with green potential; Duurzame energie. Economisch groeigebied voor Nederland met groene potentie

    Energy Technology Data Exchange (ETDEWEB)

    Sijbesma, F.; Oudeman, M.

    2010-02-15

    Research of the economic potential and options for enhancing renewable energy in the Netherlands. The following research questions were addressed: What is the current and future economic value of renewable energy in the Netherlands?; What are the areas in which the Netherlands has a unique point of departure with respect to knowledge and activities?; How can the economic potential be optimally deployed? Can the opportunities be increased by making it a key area?; What are other ways are there to enhance the economic development?. [Dutch] Onderzoek naar de economische potentie en opties ter versterking van duurzame energie in Nederland. Daarbij stonden volgende onderzoeksvragen centraal: Wat is de huidige en toekomstige economische waarde van duurzame energie in Nederland?; Op welke gebieden heeft Nederland een unieke uitgangspositie qua kennis en bedrijvigheid? Hoe is de economische potentie optimaal te benutten?; Kunnen de kansen vergroot worden door het een sleutelgebied te maken?; Welke andere manieren zijn er om de economische ontwikkeling te stimuleren?.

  19. Study of the potential of wave energy in Malaysia

    Science.gov (United States)

    Tan, Wan Ching; Chan, Keng Wai; Ooi, Heivin

    2017-07-01

    Renewable energy is generally defined as energy harnessed from resources which are naturally replenished. It is an alternative to the current conventional energy sources such as natural gas, oil and coal, which are nonrenewable. Besides being nonrenewable, the harnessing of these resources generally produce by-products which could be potentially harmful to the environment. On the contrary, the generation from renewable energy does not pose environmental degradation. Some examples of renewable energy sources are sunlight, wind, tides, waves and geothermal heat. Wave energy is considered as one of the most promising marine renewable resources and is becoming commercially viable quicker than other renewable technologies at an astonishing growth rate. This paper illustrates the working principle of wave energy converter (WEC) and the availability of wave energy in Malaysia oceans. A good understanding of the behaviour of ocean waves is important for designing an efficient WEC as the characteristics of the waves in shallow and deep water are different. Consequently, wave energy converters are categorized into three categories on shore, near shore and offshore. Therefore, the objectives of this study is ought to be carried out by focusing on the formation of waves and wave characteristics in shallow as well as in deep water. The potential sites for implementation of wave energy harvesting technology in Malaysia and the wave energy available in the respective area were analysed. The potential of wave energy in Malaysia were tabulated and presented with theoretical data. The interaction between motion of waves and heave buoys for optimum phase condition by using the mass and diameter as the variables were investigated.

  20. Separable Representation of Energy-Dependent Optical Potentials

    CERN Document Server

    Hlophe, Linda

    2015-01-01

    Background. One important ingredient for many applications of nuclear physics to astrophysics, nuclear energy, and stockpile stewardship are cross sections for reactions of neutrons with rare isotopes. Since direct measurements are often not feasible, indirect methods, e.g. (d,p) reactions, should be used. Those (d,p) reactions may be viewed as three-body reactions and described with Faddeev techniques. Purpose. Faddeev equations in momentum space have a long tradition of utilizing separable interactions in order to arrive at sets of coupled integral equations in one variable. Optical potentials representing the effective interactions in the neutron (proton) nucleus subsystem are usually non-Hermitian as well as energy-dependent. Potential matrix elements as well as transition matrix elements calculated with them must fulfill the reciprocity theorem. The purpose of this paper is to introduce a separable, energy-dependent representation of complex, energy-dependent optical potentials that fulfill reciprocity e...

  1. Estimation of energy potential of agricultural enterprise biomass

    Directory of Open Access Journals (Sweden)

    Lypchuk Vasyl

    2017-01-01

    Full Text Available Bioenergetics (obtaining of energy from biomass is one of innovative directions in energy branch of Ukraine. Correct and reliable estimation of biomass potential is essential for efficient use of it. The article reveals the issue of estimation of potential of biomass, obtained from byproducts of crop production and animal breeding, which can be used for power supply of agricultural enterprises. The given analysis was carried with application of common methodological fundamentals, revealed in the estimation of production structure of agricultural enterprises, structure of land employment, efficiency of crops growing, indicators of output of main and by-products, as well as normative (standard parameters of power output of energy raw material in relation to the chosen technology of its utilization. Results of the research prove high energy potential of byproducts of crop production and animal breeding at all of the studied enterprises, which should force its practical use.

  2. Energy life cycle assessment of rice straw bio-energy derived from potential gasification technologies.

    Science.gov (United States)

    Shie, Je-Lueng; Chang, Ching-Yuan; Chen, Ci-Syuan; Shaw, Dai-Gee; Chen, Yi-Hung; Kuan, Wen-Hui; Ma, Hsiao-Kan

    2011-06-01

    To be a viable alternative, a biofuel should provide a net energy gain and be capable of being produced in large quantities without reducing food supplies. Amounts of agricultural waste are produced and require treatment, with rice straw contributing the greatest source of such potential bio-fuel in Taiwan. Through life-cycle accounting, several energy indicators and four potential gasification technologies (PGT) were evaluated. The input energy steps for the energy life cycle assessment (ELCA) include collection, generator, torrefaction, crushing, briquetting, transportation, energy production, condensation, air pollution control and distribution of biofuels to the point of end use. Every PGT has a positive energy benefit. The input of energy required for the transportation and pre-treatment are major steps in the ELCA. On-site briquetting of refused-derived fuel (RDF) provides an alternative means of reducing transportation energy requirements. Bio-energy sources, such as waste rice straw, provide an ideal material for the bio-fuel plant.

  3. Energy modelling for economies in transition

    Energy Technology Data Exchange (ETDEWEB)

    Van Leeuwen, M.L.; Velthuijsen, J.W. [Foundation for Economic Research SEO, University of Amsterdam UvA, Amsterdam (Netherlands); Van Oostvoorn, F.; Voogt, M. [ECN Policy Study, Petten (Netherlands)

    1998-12-31

    The model system composed of a Computable General Equilibrium (CGE) E3 model and the least-cost energy sector model Energy Flow Optimization Model - Environment (EFOM-ENV) proved to be a useful support in developing long-term scenarios for several Central European and Eastern European (CEE) countries. Calculation results obtained from using the model.system could be used to support energy policy decisions in the framework of different possible future developments in energy demand and supply and related emissions, which is also consistent with macro-economic developments in the national economies. Also, and most important, the developments within the national (transition) economy could be made consistent with external developments (on a world and European Union (EU) level) that are envisioned in EC-scenarios. This facilitates the analysis of an increasing convergence process of different CEE countries towards the EU and could be useful in the policy dialogue on convergence. Empirical studies with the model system have shown that the interrelations between macro-economic indicators and important factors determining energy supply and demand could be dealt with in a transparent way. An assessment could be made of the impact of changes in economic structure, employment rate, trade balance, social security and public spending on the structure of energy demand, fuel mix, capacity requirements and related energy costs, and vice versa. Specific policy issues such as a restructuring of the Polish coal industry or determining the scope for CO2 reduction in Romania could be addressed and instruments could be identified to encounter these issues. Especially for policy makers in transition economies who are faced with many interactive changes, it is important to have a realistic insight in the scope and restrictions of future policy. Ambitions are often very high, but reaching certain objectives could be conflicting with others. Results obtained from calculations with the model

  4. Potential for energy conservation in the glass industry

    Energy Technology Data Exchange (ETDEWEB)

    Garrett-Price, B.A.; Fassbender, A.G.; Bruno, G.A.

    1986-06-01

    While the glass industry (flat glass, container glass, pressed and blown glass, and insulation fiber glass) has reduced its specific energy use (Btu/ton) by almost 30% since 1972, significant potential for further reduction still remains. State-of-the-art technologies are available which could lead to incremental improvements in glass industry energy productivity; however, these technologies must compete for capital with projects undertaken for other reasons (e.g., capacity expansion, equipment rebuild, labor cost reduction, product quality improvement, or compliance with environmental, health or safety regulations). Narrowing profit margins in the large tonnage segments of the glass industry in recent years and the fact that energy costs represent less than 25% of the value added in glass manufacture have combined to impede the widespread adoption of many state-of-the-art conservation technologies. Savings in energy costs alone have not provided the incentive to justify the capital expenditures required to realize the energy savings. Beyond implementation of state-of-the-art technologies, significant potential energy savings could accrue from advanced technologies which represent a radical departure from current glass making technology. Long-term research and development (R and D) programs, which address the technical and economic barriers associated with advanced, energy-conserving technologies, offer the opportunity to realize this energy-saving potential.

  5. Framework for State-Level Renewable Energy Market Potential Studies

    Energy Technology Data Exchange (ETDEWEB)

    Kreycik, C.; Vimmerstedt, L.; Doris, E.

    2010-01-01

    State-level policymakers are relying on estimates of the market potential for renewable energy resources as they set goals and develop policies to accelerate the development of these resources. Therefore, accuracy of such estimates should be understood and possibly improved to appropriately support these decisions. This document provides a framework and next steps for state officials who require estimates of renewable energy market potential. The report gives insight into how to conduct a market potential study, including what supporting data are needed and what types of assumptions need to be made. The report distinguishes between goal-oriented studies and other types of studies, and explains the benefits of each.

  6. Technical Potential of Solar Energy to Address Energy Poverty and Avoid GHG Emissions in Africa

    Energy Technology Data Exchange (ETDEWEB)

    Cowlin, S. C.; Heimiller, D.; Bilello, D.; Renne, D.

    2008-01-01

    This analysis explores the technical potential of photovoltaics (PV) or concentrating solar power (CSP) to address energy poverty in Africa through a geographic information system (GIS) screening of solar resource data developed by the U.S. Department of Energy's National Renewable Energy Laboratory (NREL).

  7. Potential Crash Location (PCL) Model

    Science.gov (United States)

    2014-02-05

    LCA ) model provides a method for calculating how large the actual lethal area at the site of impact would be. The LCA model is described in a...helicopter failures. The crash location calculations are just one portion of the TLS tool, the other portion is LCA . Although the LCA is not

  8. Consequences of converting graded to action potentials upon neural information coding and energy efficiency.

    Science.gov (United States)

    Sengupta, Biswa; Laughlin, Simon Barry; Niven, Jeremy Edward

    2014-01-01

    Information is encoded in neural circuits using both graded and action potentials, converting between them within single neurons and successive processing layers. This conversion is accompanied by information loss and a drop in energy efficiency. We investigate the biophysical causes of this loss of information and efficiency by comparing spiking neuron models, containing stochastic voltage-gated Na(+) and K(+) channels, with generator potential and graded potential models lacking voltage-gated Na(+) channels. We identify three causes of information loss in the generator potential that are the by-product of action potential generation: (1) the voltage-gated Na(+) channels necessary for action potential generation increase intrinsic noise and (2) introduce non-linearities, and (3) the finite duration of the action potential creates a 'footprint' in the generator potential that obscures incoming signals. These three processes reduce information rates by ∼50% in generator potentials, to ∼3 times that of spike trains. Both generator potentials and graded potentials consume almost an order of magnitude less energy per second than spike trains. Because of the lower information rates of generator potentials they are substantially less energy efficient than graded potentials. However, both are an order of magnitude more efficient than spike trains due to the higher energy costs and low information content of spikes, emphasizing that there is a two-fold cost of converting analogue to digital; information loss and cost inflation.

  9. Energy Blocks — A Physical Model for Teaching Energy Concepts

    Science.gov (United States)

    Hertting, Scott

    2016-01-01

    Most physics educators would agree that energy is a very useful, albeit abstract topic. It is therefore important to use various methods to help the student internalize the concept of energy itself and its related ideas. These methods include using representations such as energy bar graphs, energy pie charts, or energy tracking diagrams. Activities and analogies like Energy Theater and Richard Feynman's blocks, as well as the popular money (or wealth) analogy, can also be very effective. The goal of this paper is to describe a physical model of Feynman's blocks that can be employed by instructors to help students learn the following energy-related concepts: 1. The factors affecting each individual mechanical energy storage mode (this refers to what has been traditionally called a form of energy, and while the Modeling Method of instruction is not the focus of this paper, much of the energy related language used is specific to the Modeling Method). For example, how mass or height affects gravitational energy; 2. Energy conservation; and 3. The graphical relationships between the energy storage mode and a factor affecting it. For example, the graphical relationship between elastic energy and the change in length of a spring.

  10. Energy Planning in Selected European Regions - Methods for Evaluating the Potential of Renewable Energy Sources

    OpenAIRE

    Sliz-Szkliniarz, Beata

    2013-01-01

    Given their potentially positive impact on climate protection and the preservation of fossil resources, alternative energy sources have become increasingly important for the energy supply over the past years. However, the questions arises what economic and ecological impacts and potential conflicts over land use resources are associated with the promotion of renewable energy production. Using the examples of three selected European Regions in Poland, France and German, the dissertation discus...

  11. 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.......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....

  12. Complex Evaluation Model of Corporate Energy Management

    OpenAIRE

    Ágnes Kádár Horváth

    2014-01-01

    With the ever increasing energy problems at the doorstep alongside with political, economic, social and environmental challenges, conscious energy management has become of increasing importance in corporate resource management. Rising energy costs, stricter environmental and climate regulations as well as considerable changes in the energy market require companies to rationalise their energy consumption and cut energy costs. This study presents a complex evaluation model of corporate energy m...

  13. Energy: modelization and econometrics. Proceedings of colloquium

    Energy Technology Data Exchange (ETDEWEB)

    Fericelli, J.; Lesourd, J.B.

    1985-01-01

    The document presents the communications of the ''applied econometric association'' symposium and introduces the description of various French and foreigner models: analysis of the energy demand and production functions with energy input. A detailed evaluation of the Translog function applied to energy is described. Other energy economic aspects are approched: energy prices and costs, energetic balances, energy management in enterprises, impact evaluation of alternative energy policies.

  14. Warm body temperature facilitates energy efficient cortical action potentials.

    Directory of Open Access Journals (Sweden)

    Yuguo Yu

    Full Text Available The energy efficiency of neural signal transmission is important not only as a limiting factor in brain architecture, but it also influences the interpretation of functional brain imaging signals. Action potential generation in mammalian, versus invertebrate, axons is remarkably energy efficient. Here we demonstrate that this increase in energy efficiency is due largely to a warmer body temperature. Increases in temperature result in an exponential increase in energy efficiency for single action potentials by increasing the rate of Na(+ channel inactivation, resulting in a marked reduction in overlap of the inward Na(+, and outward K(+, currents and a shortening of action potential duration. This increase in single spike efficiency is, however, counterbalanced by a temperature-dependent decrease in the amplitude and duration of the spike afterhyperpolarization, resulting in a nonlinear increase in the spike firing rate, particularly at temperatures above approximately 35°C. Interestingly, the total energy cost, as measured by the multiplication of total Na(+ entry per spike and average firing rate in response to a constant input, reaches a global minimum between 37-42°C. Our results indicate that increases in temperature result in an unexpected increase in energy efficiency, especially near normal body temperature, thus allowing the brain to utilize an energy efficient neural code.

  15. Wind energy potential analysis in Al-Fattaih-Darnah

    Energy Technology Data Exchange (ETDEWEB)

    Tjahjana, Dominicus Danardono Dwi Prija, E-mail: danar1405@gmail.com; Salem, Abdelkarim Ali, E-mail: keemsalem@gmail.com; Himawanto, Dwi Aries, E-mail: dwiarieshimawanto@gmail.com [University of Sebelas Maret, Jl. Ir. Sutami No. 36 A, Surakarta, Indonesia 57126 (Indonesia)

    2016-03-29

    In this paper the wind energy potential in Al-Fattaih-Darnah, Libya, had been studied. Wind energy is very attractive because it can provide a clean and renewable energy. Due mostly to the uncertainty caused by the chaotic characteristics of wind near the earth’s surface, wind energy characteristic need to be investigated carefully in order to get consistent power generation. This investigation was based on one year wind data measured in 2003. As a result of the analysis, wind speed profile and wind energy potential have been developed. The wind energy potential of the location is looked very promising to generate electricity. The annual wind speed of the site is 8.21 m/s and the wind speed carrying maximum energy is 7.97 m/s. The annual power density of the site is classified into class 3. The Polaris P50-500 wind turbine can produce 768.39 M Wh/year and has capacity factor of 17.54%.

  16. Evaluating potential renewable energy resources in Poultney, Vermont: A GIS-based approach to supporting rural community energy planning

    Energy Technology Data Exchange (ETDEWEB)

    Van Hoesen, John; Letendre, Steven (Green Mountain College, One Brennan Circle, Poultney, VT 05764, US)

    2010-09-15

    The current electricity infrastructure in the United States relies on a centralized distribution network that carries a heavy carbon footprint and is susceptible to disruption and failure. Rural communities are more susceptible to longer term interruption and should strive towards a local distributed energy model. This transition will require municipalities to engage with and seek input from community stakeholders. This paper describes a possible model for supporting rural community energy projects using a Geographic Information System (GIS), which was used to develop an inventory of energy resource potential in a rural Vermont town for biomass, wind, and solar technologies. (author)

  17. Bioluminescence Potential Modeling and Forecasting

    Science.gov (United States)

    2013-05-22

    bioluminescence in the wakes of ships, breaking waves, around the bodies of rapidly moving fish and mammals , and from simple agitation of the water with one’s hand...history of brilliant displays of bioluminescence in the wakes of ships, breaking waves, around the bodies of rapidly moving fish and mammals , and from...during the earlier stages of upwelling development. Later, the observed deep offshore BL potential maximum disappeared and became a shallower and much

  18. Rogeaulito: a world energy scenario modeling tool for transparent energy system thinking

    Directory of Open Access Journals (Sweden)

    Léo eBenichou

    2014-01-01

    Full Text Available Rogeaulito is a world energy model for scenario building developed by the European think tank The Shift Project. It’s a tool to explore world energy choices from a very long-term and systematic perspective. As a key feature and novelty it computes energy supply and demand independently from each other revealing potentially missing energy supply by 2100. It is further simple to use, didactic and open source. As such, it targets a broad user group and advocates for reproducibility and transparency in scenario modeling as well as model-based learning. Rogeaulito applies an engineering approach using disaggregated data in a spreadsheet model.

  19. Systems Engineering Model for ART Energy Conversion

    Energy Technology Data Exchange (ETDEWEB)

    Mendez Cruz, Carmen Margarita [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Rochau, Gary E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Wilson, Mollye C. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-02-01

    The near-term objective of the EC team is to establish an operating, commercially scalable Recompression Closed Brayton Cycle (RCBC) to be constructed for the NE - STEP demonstration system (demo) with the lowest risk possible. A systems engineering approach is recommended to ensure adequate requirements gathering, documentation, and mode ling that supports technology development relevant to advanced reactors while supporting crosscut interests in potential applications. A holistic systems engineering model was designed for the ART Energy Conversion program by leveraging Concurrent Engineering, Balance Model, Simplified V Model, and Project Management principles. The resulting model supports the identification and validation of lifecycle Brayton systems requirements, and allows designers to detail system-specific components relevant to the current stage in the lifecycle, while maintaining a holistic view of all system elements.

  20. Renewable energy technologies adoption in Kazakhstan: potentials, barriers and solutions

    Science.gov (United States)

    Karatayev, Marat; Marazza, Diego; Contin, Andrea

    2015-04-01

    The growth in environmental pollution alongside an increasing demand for electricity in Kazakhstan calls for a higher level of renewable energy penetration into national power systems. Kazakhstan has great potential for renewable energies from wind, solar, hydro and biomass resources that can be exploited for electricity production. In 2013, the Kazakhstani Ministry of Energy initiated a new power development plan, which aims to bring the share of renewable energy to 3% by 2020 rising to 30% by 2030 and 50% by 2050. The current contribution of renewable energy resources in the national electricity mix, however, is less than 1%. As a developing country, Kazakhstan has faced a number of barriers to increase renewable energy use, which have to be analysed and translated into a comprehensive renewable energy policy framework. This study presents an overview of the current conditions of renewable energy development in Kazakhstan. Secondly, it identifies and describes the main barriers that prevent diffusion of renewable energy technologies in Kazakhstan. Finally, the paper provides solutions to overcome specific barriers in order to successfully develop a renewable energy technology sector in Kazakhstan.

  1. Investigation into the potential of energy storage to tackle intermittency in renewable energy generation

    OpenAIRE

    Barbour, Edward

    2013-01-01

    Renewable Energy is by nature intermittent and matching the supply of energy to specific time dependent demand poses huge challenges. Energy storage is a useful tool in handling this temporal disparity, although except for regions very suitable for pumped hydroelectric storage schemes, it suffers from being technically difficult to implement and costly as a result. This study investigates the potential benefits offered by various scales of energy storage to different types of r...

  2. Alpine Windharvest: development of information base regarding potentials and the necessary technical, legal and socio-economic conditions for expanding wind energy in the Alpine Space - CFD modelling evaluation - Summary of WindSim CFD modelling procedure and validation

    Energy Technology Data Exchange (ETDEWEB)

    Schaffner, B.; Cattin, R. [Meteotest, Berne (Switzerland)

    2005-07-01

    This report presents the development work carried out by the Swiss meteorology specialists of the company METEOTEST as part of a project carried out together with the Swiss wind-energy organisation 'Suisse Eole'. The framework for the project is the EU Interreg IIIB Alpine Space Programme, a European Community Initiative Programme funded by the European Regional Development Fund. The project investigated the use of digital relief-analysis. The report describes the development of a basic information system to aid the investigation of the technical, legal and socio-economical conditions for the use of wind energy in the alpine area. The report deals with the use of computational fluid dynamics and wind simulation modelling techniques and their validation. Recommendations on the use of the results are made.

  3. Use of Empirically-Based Models to Evaluate the Potential of Energy Efficiency and Forest Carbon Sequestration for Mitigating Climate Change

    Science.gov (United States)

    Murphy, Rose Elise

    This dissertation shows the hydrogen reactivity and stability of solid-state films and solutions of nanoparticles (NPs) for potential applications in hydrogen sensing and homogeneous catalysis of organic reactions. Mainly, this dissertation describes 1) the chemical synthesis of Pd and PdAg nanoparticles coated with various organic ligands and with different metal compositions, 2) the stability of solutions containing Pd and PdAg NPs in the presence of hydrogen, 3) the hydrogen sensing properties of films of NPs deposited onto Au microelectrodes, and 4) the evaluation of the catalytic activity of Pd and PdAg NPs for hydrogenation/isomerization of allyl alcohol. We chemically synthesized Pd and Pd-containing alloy (PdAg) NPs stabilized with alkanethiolates (CnS, n = 4, 6, 8, 12, 16, and 18), alkylamines (CnNH2, n = 8, 12, and 16), and mixed C8NH2/C6S ligands. All of the NPs were easily prepared and fully characterized by various analytical techniques to get their composition. By varying the initial mole ratio of Pd/CnNH2 and the chain lengths of CnNH2 and Cn S, we were able to control the size, distribution, and stability of the NPs. When these NPs were exposed to 100% hydrogen, different stability was observed depending on the functionality and composition of Pd and PdAg NPs. While CnS Pd NPs (n ≥ 6) had high stability against H2-induced aggregation because of the strong Pd-S interaction and moderate-sized alkane chain, the 6x and 12x C16NH2 Pd and Pd 91Ag9 NPs exhibited the highest stability likely due to the formation of a bilayer of ligands on the Pd core that prevents the NP aggregation. For mixed ligand C8NH2/C6S Pd NPs, the stability strongly depended on the C8NH2/C6S ratio on the Pd NPs. The Pd NPs coated with ˜3:1 or less C8NH2/C6S ligands showed excellent stability against H 2-induced aggregation in solution. In the area of hydrogen sensing, neither C6S Pd nor C8NH2 Pd NPs displayed desirable sensing attributes. By synthesizing C8NH2 /C6S mixed Pd NPs

  4. Holographic tachyon model of dark energy

    OpenAIRE

    Setare, M.R.

    2007-01-01

    In this paper we consider a correspondence between the holographic dark energy density and tachyon energy density in FRW universe. Then we reconstruct the potential and the dynamics of the tachyon field which describe tachyon cosmology.

  5. Communication: Fitting potential energy surfaces with fundamental invariant neural network

    Science.gov (United States)

    Shao, Kejie; Chen, Jun; Zhao, Zhiqiang; Zhang, Dong H.

    2016-08-01

    A more flexible neural network (NN) method using the fundamental invariants (FIs) as the input vector is proposed in the construction of potential energy surfaces for molecular systems involving identical atoms. Mathematically, FIs finitely generate the permutation invariant polynomial (PIP) ring. In combination with NN, fundamental invariant neural network (FI-NN) can approximate any function to arbitrary accuracy. Because FI-NN minimizes the size of input permutation invariant polynomials, it can efficiently reduce the evaluation time of potential energy, in particular for polyatomic systems. In this work, we provide the FIs for all possible molecular systems up to five atoms. Potential energy surfaces for OH3 and CH4 were constructed with FI-NN, with the accuracy confirmed by full-dimensional quantum dynamic scattering and bound state calculations.

  6. Saturation wind power potential and its implications for wind energy.

    Science.gov (United States)

    Jacobson, Mark Z; Archer, Cristina L

    2012-09-25

    Wind turbines convert kinetic to electrical energy, which returns to the atmosphere as heat to regenerate some potential and kinetic energy. As the number of wind turbines increases over large geographic regions, power extraction first increases linearly, but then converges to a saturation potential not identified previously from physical principles or turbine properties. These saturation potentials are >250 terawatts (TW) at 100 m globally, approximately 80 TW at 100 m over land plus coastal ocean outside Antarctica, and approximately 380 TW at 10 km in the jet streams. Thus, there is no fundamental barrier to obtaining half (approximately 5.75 TW) or several times the world's all-purpose power from wind in a 2030 clean-energy economy.

  7. Global energy modeling - A biophysical approach

    Energy Technology Data Exchange (ETDEWEB)

    Dale, Michael

    2010-09-15

    This paper contrasts the standard economic approach to energy modelling with energy models using a biophysical approach. Neither of these approaches includes changing energy-returns-on-investment (EROI) due to declining resource quality or the capital intensive nature of renewable energy sources. Both of these factors will become increasingly important in the future. An extension to the biophysical approach is outlined which encompasses a dynamic EROI function that explicitly incorporates technological learning. The model is used to explore several scenarios of long-term future energy supply especially concerning the global transition to renewable energy sources in the quest for a sustainable energy system.

  8. Capacitive technology for energy extraction from chemical potential differences

    OpenAIRE

    Bastos Sales, B.

    2013-01-01

    This thesis introduces the principle of Capacitive energy extraction based on Donnan Potential (CDP) to exploit salinity gradients. It also shows the fundamental characterization and improvements of CDP. An alternative application of this technology aimed at thermal gradients was tested.   Chapter 2 introduces the principle and initial tests. The entropy increase of mixing two solutions of different salt concentrations can be harnessed to generate electrical energy. Worldwide, the potent...

  9. Reaction Path Optimization with Holonomic Constraints and Kinetic Energy Potentials.

    Science.gov (United States)

    Brokaw, Jason B; Haas, Kevin R; Chu, Jhih-Wei

    2009-08-11

    Two methods are developed to enhance the stability, efficiency, and robustness of reaction path optimization using a chain of replicas. First, distances between replicas are kept equal during path optimization via holonomic constraints. Finding a reaction path is, thus, transformed into a constrained optimization problem. This approach avoids force projections for finding minimum energy paths (MEPs), and fast-converging schemes such as quasi-Newton methods can be readily applied. Second, we define a new objective function - the total Hamiltonian - for reaction path optimization, by combining the kinetic energy potential of each replica with its potential energy function. Minimizing the total Hamiltonian of a chain determines a minimum Hamiltonian path (MHP). If the distances between replicas are kept equal and a consistent force constant is used, then the kinetic energy potentials of all replicas have the same value. The MHP in this case is the most probable isokinetic path. Our results indicate that low-temperature kinetic energy potentials (optimization and can significantly reduce the required steps of minimization by 2-3 times without causing noticeable differences between a MHP and MEP. These methods are applied to three test cases, the C7eq-to-Cax isomerization of an alanine dipeptide, the (4)C1-to-(1)C4 transition of an α-d-glucopyranose, and the helix-to-sheet transition of a GNNQQNY heptapeptide. By applying the methods developed in this work, convergence of reaction path optimization can be achieved for these complex transitions, involving full atomic details and a large number of replicas (>100). For the case of helix-to-sheet transition, we identify pathways whose energy barriers are consistent with experimental measurements. Further, we develop a method based on the work energy theorem to quantify the accuracy of reaction paths and to determine whether the atoms used to define a path are enough to provide quantitative estimation of energy barriers.

  10. Potential of Sugarcane in Modern Energy Development in Southern Africa

    OpenAIRE

    Souza, Simone P.; Horta Nogueira, Luiz A.; Watson, Helen K.; Lynd, Lee Rybeck; Elmissiry, Mosad; Cortez,Luís A.B.

    2016-01-01

    For more than half of the Southern African population, human development is limited by a lack of access to electricity and modern energy for cooking. Modern bioenergy merits consideration as one means to address this situation in areas where sufficient arable land is available. While numerous studies have concluded that Africa has significant biomass potential, they do not indicate by how much it can effectively reduce the use of traditional biomass and provide more accessible energy, especia...

  11. Energy Potential Mapping: Visualising Energy Characteristics for the Exergetic Optimisation of the Built Environment

    Directory of Open Access Journals (Sweden)

    Michiel Fremouw

    2013-01-01

    Full Text Available It is difficult to fully satisfy the energy demand of today’s society with renewables. Nevertheless, most of the energy we use is lost as non-functional waste energy, whereas a large part of the built environment’s energy demand is only for low-quality energy, so the initial demand for primary, high-quality energy can be reduced by more effective usage, such as by low-exergy means. Gaining insight into the parameters of energy demands and local renewable and residual energy potentials enables matching energy demand with a fitting potential, not only concerning quantity but taking into account location, temporality and quality as well. The method of Energy Potential Mapping (EPM aims to visualise the energy potentials and demands by making information of quantity, quality and location of demand and supply accessible. The aspect of quality specifically applies to heat and cold. The methodology of EPM will be described and explained with case studies. The focus specifically lies on mapping heat (and cold, one of the main reasons for energy demand in the built environment. The visualisation of exergy, to be simplified as the quality of energy, becomes an extra parameter in the case of Dutch Heat Maps. These maps can help finding opportunities of practical implementations of exchanging or cascading heat or cold. This way EPM and Heat Mapping (HM enables application of exergy principles in the built environment. EPM and HM can be seen as a local energy catalogue and can be useful in spatial planning for energy-based urban and rural plans.

  12. Assessing the wind energy potential projects in Algeria

    Energy Technology Data Exchange (ETDEWEB)

    Himri, Y. [Electricity and Gas National Enterprise (SONELGAZ) Bechar (Algeria); Laboratory Renewable Energy and Thermal, University of Bechar (Algeria); Himri, S. [University of Bechar, Department of Fundamental Sciences (Algeria); Boudghene Stambouli, A. [University of Sciences and Technology of Oran, Department of Electronic (Algeria)

    2009-10-15

    A research program is under way in the SONELGAZ R and D Office with the aim of studying the potential of wind energy in Algeria. This paper presents an analysis of recently collected hourly wind data over a period of almost 5 years between 2002 and 2006, from four selected sites as well as preliminary evaluation of the wind energy potential. The results showed that Tindouf and Dely Brahim sites have higher wind energy potential with annual wind speed average of 5.8 and 5.7 m/s respectively at height of 17 m above ground level (AGL). The two sites are candidates for remote area wind energy applications. The Ouled Fayet and Marsa Ben M'hidi sites wind speed data indicated that the two sites have lower annual wind speed averages between 3.9-4.7 m/s at 17 m AGL. That makes the two sites candidates for installation of windmills to provide water for drinking and small scale irrigation purposes Brief description of the equipment, is also performed. Finally the aim of this work is only a preliminary study in order to assess wind energy analysis in Algeria and give useful insights to engineers and experts dealing with wind energy. (author)

  13. Mapping Thermal Energy Resource Potentials from Wastewater Treatment Plants

    Directory of Open Access Journals (Sweden)

    Georg Neugebauer

    2015-09-01

    Full Text Available Wastewater heat recovery via heat exchangers and heat pumps constitutes an environmentally friendly, approved and economically competitive, but often underestimated technology. By introducing the spatial dimension in feasibility studies, the results of calculations change considerably. This paper presents a methodology to estimate thermal energy resource potentials of wastewater treatment plants taking spatial contexts into account. In close proximity to settlement areas, wastewater energy can ideally be applied for heating in mixed-function areas, which very likely have a continuous heat demand and allow for an increased amount of full-load hours compared to most single-use areas. For the Austrian case, it is demonstrated that the proposed methodology leads to feasible results and that the suggested technology might reduce up to 17% of the Austrian global warming potential of room heating. The method is transferrable to other countries as the input data and calculation formula are made available. A broad application of wastewater energy with regard to spatial structures and spatial development potentials can lead to (1 increasing energy efficiency by using a maximum of waste heat and (2 a significant reduction of (fossil energy consumption which results in a considerable reduction of the global warming potential of the heat supply (GWP if electricity from renewables is used for the operation of heat pumps.

  14. Calculating vibrational spectra using modified Shepard interpolated potential energy surfaces.

    Science.gov (United States)

    Evenhuis, Christian R; Manthe, Uwe

    2008-07-14

    A potential energy interpolation approach based on modified Shepard interpolation and specifically designed for calculation of vibrational states is presented. The importance of the choice of coordinates for the rate of convergence is demonstrated. Studying the vibrational states of the water molecule as a test case, a coordinate system comprised of inverse bond distances and trigonometric functions of the bond angle is found to be particularly efficient. Different sampling schemes used to locate the reference points in the modified Shepard interpolation are investigated. A final scheme is recommended, which allows the construction of potential energy surfaces to sub-wave-number accuracy.

  15. Potentials and market prospects of wind energy in Vojvodina

    Directory of Open Access Journals (Sweden)

    Katić Vladimir A.

    2012-01-01

    Full Text Available The paper presents an overview of the wind energy potentials, technologies and market prospects in the Autonomous Province of Vojvodina, the region of Serbia with the most suitable location for exploitation of wind energy. The main characteristics of the region have been presented regarding wind energy and electric, road, railway and waterway infrastructure. The wind farm interconnection with the public grid is explained. The most suitable locations for the wind farms are presented, with present situation and future prospects of wind market in Vojvodina.

  16. Biohydrogen production as a potential energy fuel in South Africa

    Directory of Open Access Journals (Sweden)

    P.T. Sekoai

    2015-06-01

    Full Text Available Biohydrogen production has captured increasing global attention due to it social, economic and environmental benefits. Over the past few years, energy demands have been growing significantly in South Africa due to rapid economic and population growth. The South African parastatal power supplier i.e. Electricity Supply Commission (ESKOM has been unable to meet the country’s escalating energy needs. As a result, there have been widespread and persistent power cuts throughout the country. This prompts an urgent need for exploration and implementation of clean and sustainable energy fuels like biohydrogen production in order to address this crisis. Therefore, this paper discusses the current global energy challenges in relation to South Africa’s problems. It then examines the feasibility of using biohydrogen production as a potential energy fuel in South Africa. Finally, it reviews the hydrogen-infrastructure development plans in the country.

  17. Analyses on Energy Saving Potential Based on Large-scale Public Buildings Energy Consumption

    Directory of Open Access Journals (Sweden)

    Xuping Chen

    2012-08-01

    Full Text Available To analyze large-scale public buildings’ energy-saving potential is one of the methods to realize scientific energy control management and service. This method aims at a typical public building’s powerconsumed system. Through analyzing and comparing the consumption data, it succeeds in analyzing the use efficiency of building power, consumption level and economic effects of the energy utilization. More over, this method has a quantity analysis on the power-consumed unit’s building usage, so that it is able to find the unit’s energy-saving potential. Its bases of all analyses are building energy balance and analyzing theory of energy cost, analyzing theory of engineering economy and environment and rational distribution theory of energy utilization system.

  18. Fossil energy savings potential of sugar cane bio-energy systems

    DEFF Research Database (Denmark)

    Nguyen, Thu Lan T; Hermansen, John Erik; Sagisaka, Masayuki

    2009-01-01

    One important rationale for bio-energy systems is their potential to save fossil energy. Converting a conventional sugar mill into a bio-energy process plant would contribute to fossil energy savings via the extraction of renewable electricity and ethanol substituting for fossil electricity...... and gasoline, respectively. This paper takes a closer look at the Thai sugar industry and examines two practical approaches that will enhance fossil energy savings. The first one addresses an efficient extraction of energy in the form of electricity from the excess bagasse and cane trash. The second while...... proposing to convert molasses or sugar cane to ethanol stresses the use of bagasse as well as distillery spent wash to replace coal in meeting ethanol plants' energy needs. The savings potential achieved with extracting ethanol from surplus sugar versus current practice in sugar industry in Thailand amounts...

  19. Potentials and policy implications of energy and material efficiency improvement

    Energy Technology Data Exchange (ETDEWEB)

    Worrell, Ernst; Levine, Mark; Price, Lynn; Martin, Nathan; van den Broek, Richard; Block, Kornelis

    1997-01-01

    There is a growing awareness of the serious problems associated with the provision of sufficient energy to meet human needs and to fuel economic growth world-wide. This has pointed to the need for energy and material efficiency, which would reduce air, water and thermal pollution, as well as waste production. Increasing energy and material efficiency also have the benefits of increased employment, improved balance of imports and exports, increased security of energy supply, and adopting environmentally advantageous energy supply. A large potential exists for energy savings through energy and material efficiency improvements. Technologies are not now, nor will they be, in the foreseeable future, the limiting factors with regard to continuing energy efficiency improvements. There are serious barriers to energy efficiency improvement, including unwillingness to invest, lack of available and accessible information, economic disincentives and organizational barriers. A wide range of policy instruments, as well as innovative approaches have been tried in some countries in order to achieve the desired energy efficiency approaches. These include: regulation and guidelines; economic instruments and incentives; voluntary agreements and actions, information, education and training; and research, development and demonstration. An area that requires particular attention is that of improved international co-operation to develop policy instruments and technologies to meet the needs of developing countries. Material efficiency has not received the attention that it deserves. Consequently, there is a dearth of data on the qualities and quantities for final consumption, thus, making it difficult to formulate policies. Available data, however, suggest that there is a large potential for improved use of many materials in industrialized countries.

  20. Models of Energy Saving Systems

    DEFF Research Database (Denmark)

    Nørgård, Jørgen Stig

    1999-01-01

    The paper first describes the concepts and methods around energy saving, such as energy chain, energy services, end-use technologies, secondary energy, etc. Next are discussed the problems of defining and adding energy services and hence end-use energy efficiency or intensity. A section is devote...... service level and technology are demonstrated as the main determinants of future energy consumption. In the concluding remarks, the main flaws of present energy policy and some visions of the future are discussed.......The paper first describes the concepts and methods around energy saving, such as energy chain, energy services, end-use technologies, secondary energy, etc. Next are discussed the problems of defining and adding energy services and hence end-use energy efficiency or intensity. A section is devoted...... to what is termed lifestyle efficiency, including the cultural values and the ability of the economy to provide the services wanted. As explained, integrated resource planning with its optimizing the whole energy chain cannot be combined with sub-optimizing part of it, for instance the supply technology...

  1. Models of Energy Saving Systems

    DEFF Research Database (Denmark)

    Nørgård, Jørgen Stig

    1999-01-01

    The paper first describes the concepts and methods around energy saving, such as energy chain, energy services, end-use technologies, secondary energy, etc. Next are discussed the problems of defining and adding energy services and hence end-use energy efficiency or intensity. A section is devote...... service level and technology are demonstrated as the main determinants of future energy consumption. In the concluding remarks, the main flaws of present energy policy and some visions of the future are discussed.......The paper first describes the concepts and methods around energy saving, such as energy chain, energy services, end-use technologies, secondary energy, etc. Next are discussed the problems of defining and adding energy services and hence end-use energy efficiency or intensity. A section is devoted...... to what is termed lifestyle efficiency, including the cultural values and the ability of the economy to provide the services wanted. As explained, integrated resource planning with its optimizing the whole energy chain cannot be combined with sub-optimizing part of it, for instance the supply technology...

  2. Modelling renewable energy economy in Ghana with autometrics

    Energy Technology Data Exchange (ETDEWEB)

    Ackah, Ishmael; Asomani, Mcomari [Africa Centre for Energy Policy, Accra (Ghana); Kwame Nkrumah Univ. of Science and Technology, Kumasi (Ghana)

    2015-04-15

    Renewable energy consumption has been identified as a potential solution to the intermittent power supply in Ghana. Recently, a Renewable Energy Act has been passed which has a target of 10% of renewable energy component in Ghana's energy mix by 2020. Whilst effort is been made to enhance supply through feed in tariffs, education and tax reduction on renewable energy related equipment, there is the need to understand the drivers of renewable energy demand. In this study, the general unrestricted model through Autometrics is used to estimate the determinants of renewable energy demand in Ghana. The results indicate that both economic factors and non-economic affect the demand for renewable energy. In addition, the underlying energy demand trend exhibits energy using behaviour. The study recommends that economic factors such as consumer subsidies should be considered when promoting renewable energy demand.

  3. Global Potential of Energy Efficiency Standards and Labeling Programs

    Energy Technology Data Exchange (ETDEWEB)

    McNeil, Michael A; McNeil, Michael A.; Letschert, Virginie; de la Rue du Can, Stephane

    2008-06-15

    This report estimates the global potential reductions in greenhouse gas emissions by 2030 for energy efficiency improvements associated with equipment (appliances, lighting, and HVAC) in buildings by means of energy efficiency standards and labels (EES&L). A consensus has emerged among the world's scientists and many corporate and political leaders regarding the need to address the threat of climate change through emissions mitigation and adaptation. A further consensus has emerged that a central component of these strategies must be focused around energy, which is the primary generator of greenhouse gas emissions. Two important questions result from this consensus: 'what kinds of policies encourage the appropriate transformation to energy efficiency' and 'how much impact can these policies have'? This report aims to contribute to the dialogue surrounding these issues by considering the potential impacts of a single policy type, applied on a global scale. The policy addressed in this report is Energy Efficient Standards and Labeling (EES&L) for energy-consuming equipment, which has now been implemented in over 60 countries. Mandatory energy performance standards are important because they contribute positively to a nation's economy and provide relative certainty about the outcome (both timing and magnitudes). Labels also contribute positively to a nation's economy and importantly increase the awareness of the energy-consuming public. Other policies not analyzed here (utility incentives, tax credits) are complimentary to standards and labels and also contribute in significant ways to reducing greenhouse gas emissions. We believe the analysis reported here to be the first systematic attempt to evaluate the potential of savings from EES&L for all countries and for such a large set of products. The goal of the analysis is to provide an assessment that is sufficiently well-quantified and accurate to allow comparison and integration

  4. Model Potentials for a C60 Shell

    CERN Document Server

    Manson, S T; Msezane, A Z

    2016-01-01

    The spatial distribution of electric charges forming a square well potential has been analyzed. It is shown that this potential is created by two concentric spheres with a double layer of charges. A C60 shell potential has been calculated under the assumption that it is formed by the averaged charge density of a neutral atom. It is further demonstrated that the phenomenological potentials simulating the C60 shell potential belong to a family of potentials with a non-flat bottom. Two possible types of C60 model potentials are proposed and their parameters have been calculated. AMS (MOS) Subject Classification. 62P35, 81V55

  5. Energy harvesting potential of tuned inertial mass electromagnetic transducers

    Science.gov (United States)

    Asai, Takehiko; Araki, Yoshikazu; Ikago, Kohju

    2017-02-01

    The demand for developing renewable energy technologies has been growing in today's society. As one of promising renewable energy sources, large-scale energy harvesting from structural vibrations employing electromagnetic transducers has recently been proposed and considerable effort has been devoted to increase the power generation capability. In this paper, we introduce the mechanism of a tuned inertial mass electromagnetic transducer (TIMET), which can absorb vibratory energy more efficiently by tuning the parameters to adjust the system. Then we propose a new vibratory energy harvester with the TIMET and determine the parameter values for the device with a simple static admittance (SA) control law to maximize the energy harvested from a stationary stochastic disturbance. To investigate the energy harvesting potential of the TIMET further, the performance-guaranteed (PG) control and the LQG control proposed in the literature are applied as well. Then the numerical simulation studies are carried out and the effectiveness of the proposed energy harvester is examined by comparing the traditional electromagnetic transducers.

  6. Harnessing Potential Evaporation as a Renewable Energy Resource With Water-Saving Benefits

    Science.gov (United States)

    Cavusoglu, A. H.; Chen, X.; Gentine, P.; Sahin, O.

    2015-12-01

    Water's large latent heat of vaporization makes evaporation a critical component of the energy balance at the Earth's surface. An immense amount of energy drives the hydrological cycle and is an important component of various weather and climate patterns. However, the potential of harnessing evaporation has received little attention as a renewable energy resource compared to wind and solar energy. Here, we investigate the potential of harvesting energy from naturally evaporating water. Using weather data across the contiguous United States and a modified model of potential evaporation, we estimate the power availability, intermittency, and the changes in evaporation rates imposed by energy conversion. Our results indicate that natural evaporation can deliver power densities similar to existing renewable energy platforms and require little to no energy storage to match the varying power demands of urban areas. This model also predicts additional, and substantial, water savings by reducing evaporative losses. These findings suggest that evaporative energy harvesting can address significant challenges with water/energy interactions that could be of interest to the hydrology community.

  7. Potential of Using Solar Energy for Drinking Water Treatment Plant

    Science.gov (United States)

    Bukhary, S. S.; Batista, J.; Ahmad, S.

    2016-12-01

    Where water is essential to energy generation, energy usage is integral to life cycle processes of water extraction, treatment, distribution and disposal. Increasing population, climate change and greenhouse gas production challenges the water industry for energy conservation of the various water-related operations as well as limiting the associated carbon emissions. One of the ways to accomplish this is by incorporating renewable energy into the water sector. Treatment of drinking water, an important part of water life cycle processes, is vital for the health of any community. This study explores the feasibility of using solar energy for a drinking water treatment plant (DWTP) with the long-term goal of energy independence and sustainability. A 10 MGD groundwater DWTP in southwestern US was selected, using the treatment processes of coagulation, filtration and chlorination. Energy consumption in units of kWh/day and kWh/MG for each unit process was separately determined using industry accepted design criteria. Associated carbon emissions were evaluated in units of CO2 eq/MG. Based on the energy consumption and the existing real estate holdings, the DWTP was sized for distributed solar. Results showed that overall the motors used to operate the pumps including the groundwater intake pumps were the largest consumers of energy. Enough land was available around DWTP to deploy distributed solar. Results also showed that solar photovoltaics could potentially be used to meet the energy demands of the selected DWTP, but warrant the use of a large storage capacity, and thus increased costs. Carbon emissions related to solar based design were negligible compared to the original case. For future, this study can be used to analyze unit processes of other DWTP based on energy consumption, as well as for incorporating sustainability into the DWTP design.

  8. Pseudospectral Gaussian quantum dynamics: Efficient sampling of potential energy surfaces

    Science.gov (United States)

    Heaps, Charles W.; Mazziotti, David A.

    2016-04-01

    Trajectory-based Gaussian basis sets have been tremendously successful in describing high-dimensional quantum molecular dynamics. In this paper, we introduce a pseudospectral Gaussian-based method that achieves accurate quantum dynamics using efficient, real-space sampling of the time-dependent basis set. As in other Gaussian basis methods, we begin with a basis set expansion using time-dependent Gaussian basis functions guided by classical mechanics. Unlike other Gaussian methods but characteristic of the pseudospectral and collocation methods, the basis set is tested with N Dirac delta functions, where N is the number of basis functions, rather than using the basis function as test functions. As a result, the integration for matrix elements is reduced to function evaluation. Pseudospectral Gaussian dynamics only requires O ( N ) potential energy calculations, in contrast to O ( N 2 ) evaluations in a variational calculation. The classical trajectories allow small basis sets to sample high-dimensional potentials. Applications are made to diatomic oscillations in a Morse potential and a generalized version of the Henon-Heiles potential in two, four, and six dimensions. Comparisons are drawn to full analytical evaluation of potential energy integrals (variational) and the bra-ket averaged Taylor (BAT) expansion, an O ( N ) approximation used in Gaussian-based dynamics. In all cases, the pseudospectral Gaussian method is competitive with full variational calculations that require a global, analytical, and integrable potential energy surface. Additionally, the BAT breaks down when quantum mechanical coherence is particularly strong (i.e., barrier reflection in the Morse oscillator). The ability to obtain variational accuracy using only the potential energy at discrete points makes the pseudospectral Gaussian method a promising avenue for on-the-fly dynamics, where electronic structure calculations become computationally significant.

  9. Capacitive technology for energy extraction from chemical potential differences

    NARCIS (Netherlands)

    Bastos Sales, B.

    2013-01-01

    This thesis introduces the principle of Capacitive energy extraction based on Donnan Potential (CDP) to exploit salinity gradients. It also shows the fundamental characterization and improvements of CDP. An alternative application of this technology aimed at thermal gradients was tested.  

  10. ENERGY POTENTIAL OF SOLID STATE CW-MICROWAVE TRANCEIVERS

    Directory of Open Access Journals (Sweden)

    A. G. Gorelik

    2015-01-01

    Full Text Available The main parameters and block diagrams of CW-microwave transceivers are considered. The advisability of leading in conception of energy potential is founded. Qualitative assessment of three ways of CW-microwave transceivers composing is done. The some features for application of CW-microwave transceivers are discussed.

  11. Unified Technical Concepts. Module 7: Potential and Kinetic Energy.

    Science.gov (United States)

    Technical Education Research Center, Waco, TX.

    This concept module on potential and kinetic energy is one of thirteen modules that provide a flexible, laboratory-based physics instructional package designed to meet the specialized needs of students in two-year, postsecondary technical schools. Each of the thirteen concept modules discusses a single physics concept and how it is applied to each…

  12. Assessing the potential for biomass energy development in South Carolina

    Science.gov (United States)

    Roger C. Conner; Tim O. Adams; Tony G. Johnson

    2009-01-01

    An assessment of the potential for developing a sustainable biomass energy industry in South Carolina was conducted. Biomass as defined by Forest Inventory and Analysis is the aboveground dry weight of wood in the bole and limbs of live trees ≥1-inch diameter at breast height, and excludes tree foliage, seedlings, and understory...

  13. Scattering at zero energy for attractive homogeneous potentials

    DEFF Research Database (Denmark)

    Derezinski, Jan; Skibsted, Erik

    2009-01-01

    We compute up to a compact term the zero-energy scattering matrix for a class of potentials asymptotically behaving as −γ|x|−μ with 0 < μ < 2 and γ > 0. It turns out to be the propagator for the wave equation on the sphere at time ....

  14. Energy Wave Model of Atom

    Institute of Scientific and Technical Information of China (English)

    伍细如

    2015-01-01

    proton emits energy wave, electron could sits any position away from nucleus, but be the most stable just when it sits at the trough of energy wave, and this position accords with Bohr radius and Schr?dinger equation.

  15. Review of Potential Characterization Techniques in Approaching Energy and Sustainability

    Directory of Open Access Journals (Sweden)

    David J. LePoire

    2014-03-01

    Full Text Available Societal prosperity is linked to sustainable energy and a healthy environment. However, tough global challenges include increased demand for fossil fuels, while approaching peak oil production and uncertainty in the environmental impacts of energy generation. Recently, energy use was identified as a major component of economic productivity, along with capital and labor. Other environmental resources and impacts may be nearing environmental thresholds, as indicated by nine planetary environmental boundaries, many of which are linked to energy production and use. Foresight techniques could be applied to guide future actions which include emphasis on (1 energy efficiency to bridge the transition to a renewable energy economy; (2 continued research, development, and assessment of new technologies; (3 improved understanding of environment impacts including natural capital use and degradation; (4 exploration of GDP alternative measures that include both economic production and environmental impacts; and (5 international cooperation and awareness of longer-term opportunities and their associated potential scenarios. Examples from the U.S. and the international community illustrate challenges and potential.

  16. Heterobarrier for converting hot-phonon energy to electric potential

    Science.gov (United States)

    Shin, Seungha; Melnick, Corey; Kaviany, Massoud

    2013-02-01

    We show that hot phonons emitted in energy conversion or resistive processes can be converted to electric potential in heterobarrier structures. Using phonon and electron interaction kinetics and self-consistent ensemble Monte Carlo, we find the favorable conditions for unassisted absorption of hot phonons and design graded heterobarriers for their direct conversion into electric energy. Tandem barriers with nearly optical-phonon height allow for substantial potential gain without current loss. We find that 19% of hot phonons can be harvested with an optimized GaAs/AlxGa1-xAs barrier structure over a range of current and electron densities, thus enhancing the overall energy conversion efficiency and reducing waste heat.

  17. Turkey's High Temperature Geothermal Energy Resources and Electricity Production Potential

    Science.gov (United States)

    Bilgin, Ö.

    2012-04-01

    Turkey is in the first 7 countries in the world in terms of potential and applications. Geothermal energy which is an alternative energy resource has advantages such as low-cost, clean, safe and natural resource. Geothermal energy is defined as hot water and steam which is formed by heat that accumulated in various depths of the Earth's crust; with more than 20oC temperature and which contain more than fused minerals, various salts and gases than normal underground and ground water. It is divided into three groups as low, medium and high temperature. High-temperature fluid is used in electricity generation, low and medium temperature fluids are used in greenhouses, houses, airport runways, animal farms and places such as swimming pools heating. In this study high temperature geothermal fields in Turkey which is suitable for electricity production, properties and electricity production potential was investigated.

  18. Modelling energy systems for developing countries

    NARCIS (Netherlands)

    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 ind

  19. ENOR - An Energy-Model for Norway

    Directory of Open Access Journals (Sweden)

    A. Ek

    1981-01-01

    Full Text Available The Energy model for Norway, ENOR, is a dynamic, multisectoral economic stimulation model to be used for long term energy analyses. Energy sectors and energy carriers are in principle treated in the same way as other sectors and economic commodities and integrated in the same general framework. The model has a two-level structure - a central coordination module ensures economic consistency, while the behaviour of each production and consumption sector is modelled in separate sector models. The model framework is thus capable of handling both engineering and economic knowledge.

  20. Pontential energies and potential-energy tensors for subsystems: general properties

    CERN Document Server

    Caimmi, R

    2016-01-01

    With regard to generic two-component systems, the theory of first variations of global quantities is reviewed and explicit expressions are inferred for subsystem potential energies and potential-energy tensors. Performing a conceptual experiment, a physical interpretation of subsystem potential energies and potential-energy tensors is discussed. Subsystem tidal radii are defined by requiring an unbound component in absence of the other one. To this respect, a few guidance examples are presented as: (i) an embedding and an embedded homogeneous sphere; (ii) an embedding and an embedded truncated, singular isothermal sphere where related centres are sufficiently distant; (iii) a homogeneous sphere and a Roche system i.e. a mass point surrounded by a vanishing atmosphere. The results are discussed and compared with the findings of earlier investigations.

  1. Smooth models for the Coulomb potential

    CERN Document Server

    González-Espinoza, Cristina E; Karwowski, Jacek; Savin, Andreas

    2016-01-01

    Smooth model potentials with parameters selected to reproduce the spectrum of one-electron atoms are used to approximate the singular Coulomb potential. Even when the potentials do not mimic the Coulomb singularity, much of the spectrum is reproduced within the chemical accuracy. For the Hydrogen atom, the smooth approximations to the Coulomb potential are more accurate for higher angular momentum states. The transferability of the model potentials from an attractive interaction (Hydrogen atom) to a repulsive one (Harmonium and the uniform electron gas) is discussed.

  2. Modeling energy flexibility of low energy buildings utilizing thermal mass

    DEFF Research Database (Denmark)

    Foteinaki, Kyriaki; Heller, Alfred; Rode, Carsten

    2016-01-01

    the load shifting potential of an apartment of a low energy building in Copenhagen is assessed, utilizing the heat storage capacity of the thermal mass when the heating system is switched off for relieving the energy system. It is shown that when using a 4-hour preheating period before switching off...... of the external envelope and the thermal capacity of the internal walls as the main parameters that affect the load shifting potential of the apartment....... to match the production patterns, shifting demand from on-peak hours to off-peak hours. Buildings could act as flexibility suppliers to the energy system, through load shifting potential, provided that the large thermal mass of the building stock could be utilized for energy storage. In the present study...

  3. Potential Energy Savings in Refrigeration Systems Using Optimal Setpoints

    DEFF Research Database (Denmark)

    Larsen, Lars Finn Slot; Thybo, Claus

    2004-01-01

    Energy efficiency of refrigeration systems has gradually been improved with help of control schemes utilizing the more flexible components. This paper proposes an approach in line with this trend, where a suboptimal condenser pressure is found in order to minimize the energy consumption. The obje......Energy efficiency of refrigeration systems has gradually been improved with help of control schemes utilizing the more flexible components. This paper proposes an approach in line with this trend, where a suboptimal condenser pressure is found in order to minimize the energy consumption....... The objective is to give an idea of how this optimization scheme works as well as to show what amount of energy it is possible to save. A steady state model of a simple refrigeration system will be used as a basis for the optimization....

  4. Energy modeling. Volume 2: Inventory and details of state energy models

    Science.gov (United States)

    Melcher, A. G.; Underwood, R. G.; Weber, J. C.; Gist, R. L.; Holman, R. P.; Donald, D. W.

    1981-05-01

    An inventory of energy models developed by or for state governments is presented, and certain models are discussed in depth. These models address a variety of purposes such as: supply or demand of energy or of certain types of energy; emergency management of energy; and energy economics. Ten models are described. The purpose, use, and history of the model is discussed, and information is given on the outputs, inputs, and mathematical structure of the model. The models include five models dealing with energy demand, one of which is econometric and four of which are econometric-engineering end-use models.

  5. Energy model development and heating energy investigation of the Nested Thermal Envelope Design (NTED(TM))

    Science.gov (United States)

    Dixon, Elizabeth Erin

    Space heating accounts for approximately 60% of residential energy use in Canada. Minimizing envelope heat losses is one approach to reducing this percentage. Preliminary research investigated the energy-saving potential of an innovative design, referred to as Nested Thermal Envelope Design (NTED(TM)). The concept involves one insulated building inside another with dual thermal zones. Conservative modeling results from this work showed heating energy reductions of 74%. This research developed a new NTED(TM) simulation model to provide increased accuracy and gain a more complete understanding of the potential heating energy savings. The working performance was also investigated by modeling occupied-building operation. The resulting model has shown that the NTED(TM) design yields savings of 85% relative to a benchmark R-2000 building. These results improve on the preliminary values and reinforce the merit of the design as a means of achieving significant reductions in residential energy use.

  6. U.S. Building-Sector Energy Efficiency Potential

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Rich; Borgeson, Sam; Koomey, Jon; Biermayer, Peter

    2008-09-30

    This paper presents an estimate of the potential for energy efficiency improvements in the U.S. building sector by 2030. The analysis uses the Energy Information Administration's AEO 2007 Reference Case as a business-as-usual (BAU) scenario, and applies percentage savings estimates by end use drawn from several prior efficiency potential studies. These prior studies include the U.S. Department of Energy's Scenarios for a Clean Energy Future (CEF) study and a recent study of natural gas savings potential in New York state. For a few end uses for which savings estimates are not readily available, the LBNL study team compiled technical data to estimate savings percentages and costs of conserved energy. The analysis shows that for electricity use in buildings, approximately one-third of the BAU consumption can be saved at a cost of conserved energy of 2.7 cents/kWh (all values in 2007 dollars), while for natural gas approximately the same percentage savings is possible at a cost of between 2.5 and 6.9 $/million Btu. This cost-effective level of savings results in national annual energy bill savings in 2030 of nearly $170 billion. To achieve these savings, the cumulative capital investment needed between 2010 and 2030 is about $440 billion, which translates to a 2-1/2 year simple payback period, or savings over the life of the measures that are nearly 3.5 times larger than the investment required (i.e., a benefit-cost ratio of 3.5).

  7. Capabilities and accuracy of energy modelling software

    CSIR Research Space (South Africa)

    Osburn, L

    2010-11-01

    Full Text Available Energy modelling can be used in a number of different ways to fulfill different needs, including certification within building regulations or green building rating tools. Energy modelling can also be used in order to try and predict what the energy...

  8. Modeling and Simulation of Smart Energy Systems

    DEFF Research Database (Denmark)

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

    2015-01-01

    At a global level, it is essential that the world transfers from fossil fuels to renewable energy resources to minimize the implications of climate change, which has been clearly demonstrated by the Intergovernmental Panel on Climate Change (IPCC, 2007a). At a national level, for most countries......, the transition to renewable energy will improve energy security of supply, create new jobs, enhance trade, and consequently grow the national economy. However, even with such promising consequences, renewable energy only provided approximately 13% of the world's energy in 2007 (International Energy Agency, 2009a......). Therefore, identifying how to utilize more renewable energy is one of the most pressing challenges facing many countries at present. Owing to the ever-growing complexity of modern energy systems, energy-system-analysis tools are often used to analyze the potential of renewable energy in future energy...

  9. Microscopic Calculation of IBM Parameters by Potential Energy Surface Mapping

    CERN Document Server

    Bentley, I

    2011-01-01

    A coherent state technique is used to generate an Interacting Boson Model (IBM) Hamiltonian energy surface that simulates a mean field energy surface. The method presented here has some significant advantages over previous work. Specifically, that this can be a completely predictive requiring no a priori knowledge of the IBM parameters. The technique allows for the prediction of the low lying energy spectra and electromagnetic transition rates which are of astrophysical interest. Results and comparison with experiment are included for krypton, molybdenum, palladium, cadmium, gadolinium, dysprosium and erbium nuclei.

  10. IRETHERM: The geothermal energy potential of Irish radiothermal granites

    Science.gov (United States)

    Farrell, Thomas; Jones, Alan; Muller, Mark; Feely, Martin; Brock, Andrew; Long, Mike; Waters, Tim

    2014-05-01

    The IRETHERM project is developing a strategic understanding of Ireland's deep geothermal energy potential through integrated modelling of new and existing geophysical and geological data. One aspect of IRETHERM's research focuses on Ireland's radiothermal granites, where increased concentrations of radioelements provide elevated heat-production (HP), surface heat-flow (SHF) and subsurface temperatures. An understanding of the contribution of granites to the thermal field of Ireland is important to assessing the geothermal energy potential of this low-enthalpy setting. This study focuses on the Galway granite in western Ireland, and the Leinster and the buried Kentstown granites in eastern Ireland. Shallow (geothermal project. These studies yielded HP = 2-3 μWm-3 and HF = 80 mWm-2 at the Sally Gap borehole in the Northern Units of the Leinster granite, to the SW of Dublin. In the Galway granite batholith, on the west coast of Ireland, the Costelloe-Murvey granite returned HP = 7 μWm-3 and HF = 77 mWm-2, measured at the Rossaveal borehole. The buried Kentstown granite, 35 km NW of Dublin, has an associated negative Bouguer anomaly and was intersected by two mineral exploration boreholes at depths of 660 m and 490 m. Heat production is measured at 2.4 μWm-3 in core samples taken from the weathered top 30 m of the granite. The core of this study consists of a program of magnetotelluric (MT) and audio-magnetotelluric (AMT) data acquisition across the three granite bodies, over three fieldwork seasons. MT and AMT data were collected at 59 locations along two profiles over the Leinster granite. Preliminary results show that the northern units of the Leinster granite (40 km SW of Dublin) extend to depths of 2-5 km. Preliminary results from the southern profile suggest a greater thickness of granite to a depth of 6-9 km beneath the Tullow pluton, 75 km SW of Dublin. Over the Galway granite, MT and AMT data have been collected at a total of 75 sites (33 consist of only

  11. Assessment potential wind energy in the north area of Iraq

    Directory of Open Access Journals (Sweden)

    Ahmed F. Hassoon

    2013-01-01

    Full Text Available Wind energy is renewable and environment friendly, which can be connected for various end-uses. A precise knowledge of wind energy regime is a pre-requisite for the efficient planning and implementation of any wind energy project. However, due to the absence of a reliable and accurate Iraq Wind Atlas, further studies on the assessment of wind energy are necessary. The main purpose of this paper is present and perform an investigation on the wind energy potential in the northern area of Iraq. Therefore, in this study, wind data collected over a period of nearly three decades at five different locations in order to figure out the wind energy potential in this region. The data from selected stations were analyzed using the two-parameter Weibull probability distribution function. The higher probability frequency wind speed at windy month (July is found in Tuz and Tikrit stations. In Tuz the range (2.5-3.0 m/s taken about 45% from the domain wind, In Tikrit the high ranges of wind (3.5-4.0 m/s and (4.0-4.5m/s form 40.9% and 36.4% of wind speed frequency, but high frequency of low wind speed is concentrated at Biji, Kirkuk and Mosul. This is reflected on The maximum expected energy output (13.5kw/h occupied at Tikrit station. Overall The study presented here is an attempt to promote wind energy in north Iraq and to bridge the gap in order to create prospective Wind Atlas of Iraq.

  12. Hot electron mediated desorption rates calculated from excited state potential energy surfaces

    CERN Document Server

    Olsen, Thomas; Schiøtz, Jakob

    2008-01-01

    We present a model for Desorption Induce by (Multiple) Electronic Transitions (DIET/DIMET) based on potential energy surfaces calculated with the Delta Self-Consistent Field extension of Density Functional Theory. We calculate potential energy surfaces of CO and NO molecules adsorbed on various transition metal surfaces, and show that classical nuclear dynamics does not suffice for propagation in the excited state. We present a simple Hamiltonian describing the system, with parameters obtained from the excited state potential energy surface, and show that this model can describe desorption dynamics in both the DIET and DIMET regime, and reproduce the power law behavior observed experimentally. We observe that the internal stretch degree of freedom in the molecules is crucial for the energy transfer between the hot electrons and the molecule when the coupling to the surface is strong.

  13. A renewable energy policy concept for the rural district of Schmalkalden-Meiningen - Assessment of potential and modelling calculations; Potentiale und Modellrechnungen zur Nutzung erneuerbarer Energien im Landkreis Schmalkalden-Meiningen

    Energy Technology Data Exchange (ETDEWEB)

    Krah, N. [Fachhochschule Schmalkalden (Germany). Fachbereich Maschinenbau

    2001-06-01

    The publication is based on previous studies, facts, information, analyses and project results. Using this available reservoir of information, the author examines the potentials and demonstrates that the rural district of Schmalkalden-Meiningen meets all requirements and owns all means to put into place an energy policy that focuses on the use of renewable energy sources and the relevant technologies. The aspects examined are: increasing the energy efficiency; rational use of energy and development of environmentally sound energy supply; use of renewable energy sources; reducing greenhouse gas emissions. (orig./CB) [German] Die Veroeffentlichung baut auf fruehere Untersuchungen, Fakten, Daten, Erkenntnisse und Projekten auf. Unter Verwendung dieser Quellen wird ein Energiekonzept fuer den Landkreis Schmalkalden-Meiningen erarbeitet, das die Nutzung erneuerbarer Energien in den Vordergrund stellt und zeigt, dass der Landkreis alle Voraussetzungen besitzt, um die folgenden Potentiale nutzbar zu machen oder auszubauen: Energieeinsparmoeglichkeiten; rationelle, umweltfreundliche Energieversorgung; Anwendung erneuerbarer Energien; Reduzierung der Schadstoffemissionen. (orig./CB)

  14. Underwater Noise Modelling of Wave Energy Devices

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    Future large-scale implementation of wave energy converts (WECs) will introduce an anthropogenic activity in the ocean which may contribute to underwater noise. The Ocean houses several marine species with acoustic sensibility; consequently the potential impact of the underwater noise needs to be addressed. At present, there are no acoustic impact studies based on acquired data. The WEAM project (Wave Energy Acoustic Monitoring) aims at developing an underwater noise monitoring plan for WECs. The development of an acoustic monitoring plan must consider the sound propagation in the ocean, identify noise sources, understand the operational characteristics and select adequate instrumentation. Any monitoring strategy must involve in-situ measurements. However, the vast distances which sound travels within the ocean, can make in-situ measurements covering the entire area of interest, impracticable. This difficulty can be partially overcome through acoustic numerical modelling. This paper presents a synthetic study, on the application of acoustic forward modelling and the evaluation of the impact of noise produced by wave energy devices on marine mammals using criteria based on audiograms of dolphins, or other species. The idea is to illustrate the application of that methodology, and to show to what extent it allows for estimating distances of impacts due to acoustic noise.

  15. Energy potential of fruit tree pruned biomass in Croatia

    Energy Technology Data Exchange (ETDEWEB)

    Bilandzija, N.; Voca, N.; Kricka, T.; Martin, A.; Jurisic, V.

    2012-11-01

    The world's most developed countries and the European Union (EU) deem that the renewable energy sources should partly substitute fossil fuels and become a bridge to the utilization of other energy sources of the future. This paper will present the possibility of using pruned biomass from fruit cultivars. It will also present the calculation of potential energy from the mentioned raw materials in order to determine the extent of replacement of non-renewable sources with these types of renewable energy. One of the results of the intensive fruit-growing process, in post pruning stage, is large amount of pruned biomass waste. Based on the calculated biomass (kg ha{sup 1}) from intensively grown woody fruit crops that are most grown in Croatia (apple, pear, apricots, peach and nectarine, sweet cherry, sour cherry, prune, walnut, hazelnut, almond, fig, grapevine, and olive) and the analysis of combustible (carbon 45.55-49.28%, hydrogen 5.91-6.83%, and sulphur 0.18-0.21%) and non-combustible matters (oxygen 43.34-46.6%, nitrogen 0.54-1.05%, moisture 3.65-8.83%, ashes 1.52-5.39%) with impact of lowering the biomass heating value (15.602-17.727 MJ kg{sup 1}), the energy potential of the pruned fruit biomass is calculated at 4.21 PJ. (Author) 31 refs.

  16. Casimir Energies and Pressures for $\\delta$-function Potentials

    CERN Document Server

    Milton, K A

    2004-01-01

    The Casimir energies and pressures for a massless scalar field associated with $\\delta$-function potentials in 1+1 and 3+1 dimensions are calculated. For parallel plane surfaces, the results are finite, coincide with the pressures associated with Dirichlet planes in the limit of strong coupling, and for weak coupling do not possess a power-series expansion in 1+1 dimension. The relation between Casimir energies and Casimir pressures is clarified,and the former are shown to involve surface terms. The Casimir energy for a $\\delta$-function spherical shell in 3+1 dimensions has an expression that reduces to the familiar result for a Dirichlet shell in the strong-coupling limit. However, the Casimir energy for finite coupling possesses a logarithmic divergence first appearing in third order in the weak-coupling expansion, which seems unremovable. The corresponding energies and pressures for a derivative of a $\\delta$-function potential for the same spherical geometry generalizes the TM contributions of electrodyn...

  17. Residential energy efficiency: Progress since 1973 and future potential

    Science.gov (United States)

    Rosenfeld, Arthur H.

    1985-11-01

    Today's 85 million U.S. homes use 100 billion of fuel and electricity (1150/home). If their energy intensity (resource energy/ft2) were still frozen at 1973 levels, they would use 18% more. With well-insulated houses, need for space heat is vanishing. Superinsulated Saskatchewan homes spend annually only 270 for space heat, 150 for water heat, and 400 for appliances, yet they cost only 2000±1000 more than conventional new homes. The concept of Cost of Conserved Energy (CCE) is used to rank conservation technologies for existing and new homes and appliances, and to develop supply curves of conserved energy and a least cost scenario. Calculations are calibrated with the BECA and other data bases. By limiting investments in efficiency to those whose CCE is less than current fuel and electricity prices, the potential residential plus commercial energy use in 2000 AD drops to half of that estimated by DOE, and the number of power plants needed drops by 200. For the whole buildings sector, potential savings by 2000 are 8 Mbod (worth 50B/year), at an average CCE of 10/barrel.

  18. THE POTENTIAL FOR BIOMASS ENERGY IN THREE ALBANIAN REGIONS

    Directory of Open Access Journals (Sweden)

    A. Jupe

    2012-03-01

    Full Text Available Biomass combustion is amongst the oldest and the most mature technique for conversion of biomass to energy; but still a great challenge lies ahead in developing new; more efficient and environmentally sustainable -systems. In light of the European Action and the National Strategy in the energy sector; Albania has enacted a friendly policy regarding renewable energy sources; including biomass. Execution of such projects is delegated to both regional and local authorities for various technical; economic and socio-environmental considerations as well as for an integrated approach to the land use planning. This paper identifies the main sources of biomass energy in three different regions of Albania i.e. Korça; Tirana and Vlora. It shows the weight of each possibility on the total potential for energy production by biomass as well as the type and distribution of each biomass. The manner how the potential offered by forestry; agriculture and agro-industry would be utilized will; apart from availability of appropriate technology; also depend on the ability of economic operators to organize themselves efficiently while respecting environmental sustainability.

  19. Modeling the Buoyancy System of a Wave Energy Power Plant

    DEFF Research Database (Denmark)

    Pedersen, Tom S.; Nielsen, Kirsten M.

    2009-01-01

    A nonlinear dynamic model of the buoyancy system in a wave energy power plant is presented. The plant ("Wave Dragon") is a floating device using the potential energy in overtopping waves to produce power. A water reservoir is placed on top of the WD, and hydro turbines lead the water to the sea...

  20. Modeling the Buoyancy System of a Wave Energy Power Plant

    DEFF Research Database (Denmark)

    Pedersen, Tom S.; Nielsen, Kirsten M.

    2009-01-01

    A nonlinear dynamic model of the buoyancy system in a wave energy power plant is presented. The plant ("Wave Dragon") is a floating device using the potential energy in overtopping waves to produce power. A water reservoir is placed on top of the WD, and hydro turbines lead the water to the sea...

  1. 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...... 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....

  2. The potential for geothermal energy in the United Kingdom

    Energy Technology Data Exchange (ETDEWEB)

    Downing, R.A.

    1985-01-01

    This work is a review of goethermal prospects in the UK. The book summarizes the results of an investigation of Britain's geothermal energy potential by the British Geological Survey between 1977 and 1984, supported by the Department of Energy and the EEC. The assessment covers both resources and the prospects for their development. Hot groundwaters in deep sedimentary basins and heat stored in 'hot dry rocks' are considered. The structure of the basins and the nature and properties of the sediments they contain are described and illustrated with maps and diagrams.

  3. [Biomass energy utilization in microbial fuel cells: potentials and challenges].

    Science.gov (United States)

    Huang, Liping; Cheng, Shaoan

    2010-07-01

    Microbial fuel cells (MFCs) that can harvest biomass energy from organic wastes through microbial catalysis have garnered more and more attention within the past decade due to its potential benefits to ecological environment. In this article, the updated progress in MFCs is reviewed, with a focus on frontier technologies such as chamber configurations, feedstock varieties and the integration of MFCs with microbial electrolysis cells for hydrogen production. And on the other hand, the challenges like development of cost-effective electrode materials, improvement of biomass energy recovery and power output, design and optimization of commercial MFC devices are presented.

  4. Applications of GARCH models to energy commodities

    Science.gov (United States)

    Humphreys, H. Brett

    This thesis uses GARCH methods to examine different aspects of the energy markets. The first part of the thesis examines seasonality in the variance. This study modifies the standard univariate GARCH models to test for seasonal components in both the constant and the persistence in natural gas, heating oil and soybeans. These commodities exhibit seasonal price movements and, therefore, may exhibit seasonal variances. In addition, the heating oil model is tested for a structural change in variance during the Gulf War. The results indicate the presence of an annual seasonal component in the persistence for all commodities. Out-of-sample volatility forecasting for natural gas outperforms standard forecasts. The second part of this thesis uses a multivariate GARCH model to examine volatility spillovers within the crude oil forward curve and between the London and New York crude oil futures markets. Using these results the effect of spillovers on dynamic hedging is examined. In addition, this research examines cointegration within the oil markets using investable returns rather than fixed prices. The results indicate the presence of strong volatility spillovers between both markets, weak spillovers from the front of the forward curve to the rest of the curve, and cointegration between the long term oil price on the two markets. The spillover dynamic hedge models lead to a marginal benefit in terms of variance reduction, but a substantial decrease in the variability of the dynamic hedge; thereby decreasing the transactions costs associated with the hedge. The final portion of the thesis uses portfolio theory to demonstrate how the energy mix consumed in the United States could be chosen given a national goal to reduce the risks to the domestic macroeconomy of unanticipated energy price shocks. An efficient portfolio frontier of U.S. energy consumption is constructed using a covariance matrix estimated with GARCH models. The results indicate that while the electric

  5. Fossil energy savings potential of sugar cane bio-energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Thu Lan T. [Department of Agroecology, Aarhus University, Tjele (Denmark); The Joint Graduate School of Energy and Environment, King Mongkut' s University of Technology Thonburi, Bangkok (Thailand); Hermansen, John E. [Department of Agroecology, Aarhus University, Tjele (Denmark); Sagisaka, Masayuki [Institute of Science for Safety and Sustainability, National Institute of Advanced Industrial Science and Technology, Tsukuba (Japan)

    2009-11-15

    One important rationale for bio-energy systems is their potential to save fossil energy. Converting a conventional sugar mill into a bio-energy process plant would contribute to fossil energy savings via the extraction of renewable electricity and ethanol substituting for fossil electricity and gasoline, respectively. This paper takes a closer look at the Thai sugar industry and examines two practical approaches that will enhance fossil energy savings. The first one addresses an efficient extraction of energy in the form of electricity from the excess bagasse and cane trash. The second while proposing to convert molasses or sugar cane to ethanol stresses the use of bagasse as well as distillery spent wash to replace coal in meeting ethanol plants' energy needs. The savings potential achieved with extracting ethanol from surplus sugar versus current practice in sugar industry in Thailand amounts to 15 million barrels of oil a year. Whether the saving benefits could be fully realized, however, depends on how well the potential land use change resulting from an expansion of ethanol production is managed. The results presented serve as a useful guidance to formulate strategies that enable optimum utilization of biomass as an energy source. (author)

  6. Energy based prediction models for building acoustics

    DEFF Research Database (Denmark)

    Brunskog, Jonas

    2012-01-01

    In order to reach robust and simplified yet accurate prediction models, energy based principle are commonly used in many fields of acoustics, especially in building acoustics. This includes simple energy flow models, the framework of statistical energy analysis (SEA) as well as more elaborated...... principles as, e.g., wave intensity analysis (WIA). The European standards for building acoustic predictions, the EN 12354 series, are based on energy flow and SEA principles. In the present paper, different energy based prediction models are discussed and critically reviewed. Special attention is placed...

  7. A dressing of zero-range potentials and electron-molecule scattering problem at low energies

    CERN Document Server

    Leble, S B

    2002-01-01

    A dressing of a nonspherical potential, which includes $n$ zero range potentials, is considered. The dressing technique is used to improve ZRP model. Concepts of the partial waves and partial phases for non-spherical potential are used in order to perform Darboux transformation. The problem of scattering on the regular $\\hbox{X}_n$ and $\\hbox{YX}_n$ structures is studied. The possibilities of dressed ZRP are illustrated by model calculation of the low-energy electron-Silane ($\\hbox{SiH}_4$) scattering. The results are discussed. Key words: multiple scattering, silane, zero range potential.

  8. Data Network Equipment Energy Use and Savings Potential in Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Lanzisera, Steven; Nordman, Bruce; Brown, Richard E.

    2010-06-09

    Network connectivity has become nearly ubiquitous, and the energy use of the equipment required for this connectivity is growing. Network equipment consists of devices that primarily switch and route Internet Protocol (IP) packets from a source to a destination, and this category specifically excludes edge devices like PCs, servers and other sources and sinks of IP traffic. This paper presents the results of a study of network equipment energy use and includes case studies of networks in a campus, a medium commercial building, and a typical home. The total energy use of network equipment is the product of the stock of equipment in use, the power of each device, and their usage patterns. This information was gathered from market research reports, broadband market penetration studies, field metering, and interviews with network administrators and service providers. We estimate that network equipment in the USA used 18 TWh, or about 1percent of building electricity, in 2008 and that consumption is expected to grow at roughly 6percent per year to 23 TWh in 2012; world usage in 2008 was 51 TWh. This study shows that office building network switches and residential equipment are the two largest categories of energy use consuming 40percent and 30percent of the total respectively. We estimate potential energy savings for different scenarios using forecasts of equipment stock and energy use, and savings estimates range from 20percent to 50percent based on full market penetration of efficient technologies.

  9. Wind energy potential in Antakya and Iskenderun regions, Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Bilgili, M.; Sahin, B. [Cukurova Univ., Adana (Turkey). Dept. of Mechanical Engineering; Kahraman, A. [Selcuk Univ., Konya (Turkey). Faculty of Technical Education

    2004-08-01

    The aim of this study is to establish the potential and the feasibility basis for the wind energy resources in some locations of East Mediterranean region of Turkey and provide suitable data for evaluating the potential wind power. For this purpose, hourly wind data, which were observed between the years 1997 and 2001 at the meteorological stations of Antakya and Iskenderun regions, were used. The dominant wind directions, the mean values, wind speeds, wind potential and the frequency distributions were determined. The results were classified according to the height above the ground level. Finally, the wind atlas of these regions in the form of contours of constant wind speed and wind potential was produced. (author)

  10. Evaluation of global onshore wind energy potential and generation costs.

    Science.gov (United States)

    Zhou, Yuyu; Luckow, Patrick; Smith, Steven J; Clarke, Leon

    2012-07-17

    In this study, we develop an updated global estimate of onshore wind energy potential using reanalysis wind speed data, along with updated wind turbine technology performance, land suitability factors, cost assumptions, and explicit consideration of transmission distance in the calculation of transmission costs. We find that wind has the potential to supply a significant portion of the world energy needs, although this potential varies substantially by region and with assumptions such as on what types of land can be used to site wind farms. Total global economic wind potential under central assumptions, that is, intermediate between optimistic and pessimistic, is estimated to be approximately 119.5 petawatt hours per year (13.6 TW) at less than 9 cents/kWh. A sensitivity analysis of eight key parameters is presented. Wind potential is sensitive to a number of input parameters, particularly wind speed (varying by -70% to +450% at less than 9 cents/kWh), land suitability (by -55% to +25%), turbine density (by -60% to +80%), and cost and financing options (by -20% to +200%), many of which have important policy implications. As a result of sensitivities studied here we suggest that further research intended to inform wind supply curve development focus not purely on physical science, such as better resolved wind maps, but also on these less well-defined factors, such as land-suitability, that will also have an impact on the long-term role of wind power.

  11. A Dynamic Model for Energy Structure Analysis

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Energy structure is a complicated system concerning economic development, natural resources, technological innovation, ecological balance, social progress and many other elements. It is not easy to explain clearly the developmental mechanism of an energy system and the mutual relations between the energy system and its related environments by the traditional methods. It is necessary to develop a suitable dynamic model, which can reflect the dynamic characteristics and the mutual relations of the energy system and its related environments. In this paper, the historical development of China's energy structure was analyzed. A new quantitative analysis model was developed based on system dynamics principles through analysis of energy resources, and the production and consumption of energy in China and comparison with the world. Finally, this model was used to predict China's future energy structures under different conditions.

  12. Accurate global potential energy surface for the H + OH+ collision

    Science.gov (United States)

    Gannouni, M. A.; Jaidane, N. E.; Halvick, P.; Stoecklin, T.; Hochlaf, M.

    2014-05-01

    We mapped the global three-dimensional potential energy surface (3D-PES) of the water cation at the MRCI/aug-cc-pV5Z including the basis set superposition (BSSE) correction. This PES covers the molecular region and the long ranges close to the H + OH+(X3Σ-), the O + H2+(X2Σg+), and the hydrogen exchange channels. The quality of the PES is checked after comparison to previous experimental and theoretical results of the spectroscopic constants of H2O+(tilde X2B1) and of the diatomic fragments, the vibronic spectrum, the dissociation energy, and the barrier to linearity for H2O+(tilde X2B1). Our data nicely approach those measured and computed previously. The long range parts reproduce quite well the diatomic potentials. In whole, a good agreement is found, which validates our 3D-PES.

  13. Energy Perspectives In Switzerland: The Potential Of Nuclear Power

    Energy Technology Data Exchange (ETDEWEB)

    Foskolos, K.; Hardegger, P

    2005-03-01

    In 2004, discussions were started in Switzerland concerning future of energy supply, including domestic electricity generation. On behalf of the Federal Office of Energy, PSI undertook a study to evaluate the potential of future nuclear technologies, covering electricity demand, with a time horizon up to 2050. It has been shown that nuclear power plants (NPPs) of the Third Generation, similar to the ones currently under construction in several other countries, built on the existing nuclear sites in Switzerland, have the potential to replace, at competitive costs, the existing nuclear plants, and even to cover (postulated) increases in electricity demand. Because of their late maturity (expected at the earliest around 2030), NPPs of the Fourth Generation, which are currently under development, cannot play a major role in Switzerland, since, with the exception of the Leibstadt NPP, all decisions regarding replacement of the current Swiss NPPs have to be taken before 2030. (author)

  14. Schematic potential energy for interaction between isobutene and zeolite mordenite

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Serrano, L A [Programa de Crudo Maya, IMP, AP 15-805, DF 07730 (Mexico); Flores-Sandoval, C A [Programa de Crudo Maya, IMP, AP 15-805, DF 07730 (Mexico); Zaragoza, I P [Programa de Ingenieria Molecular, IMP, AP 15-805, DF 07730 (Mexico)

    2004-06-09

    A schematic representation of the potential energy for the interaction between isobutene and H mordenite was presented by using eight different positions (P1-P8) of C{sub 1} or C{sub 2} atoms located in front of the acid hydrogen (H{sup +}). In all cases a {pi} complex was formed yielding different values of the adsorption energy. In some cases of the adsorption point in P1-P8 the frontier orbitals are shown. The P8 position exhibits the highest value obtained for the adsorption energy, where the C{sub 1} atom is in front of the H{sup +}. Calculations were of all electron type employing HF/6-31G**.

  15. Market potential for optical fiber sensors in the energy sector

    Science.gov (United States)

    Bosselmann, T.

    2007-07-01

    For a long time electric power was taken as a natural unlimited resource. With globalisation the demand for energy has risen. This has brought rising prices for fossil fuels, as well as a diversification of power generation. Besides conventional fossil, nuclear plants are coming up again. Renewable energy sources are gaining importance resulting in recent boom of wind energy plants. In the past reliability and availability and an extremely long lifetime were of paramount importance. Today this has been added by cost, due to the global competition and the high fuel costs. New designs of power components have increased efficiency using lesser material. Higher efficiency causes inevitably higher stress on the materials, of which the machines are built. As a reduction of lifetime is not acceptable and maintenance costs are expected to be at a minimum, condition monitoring systems are going to being used now. This offers potentials for fibre optic sensor application.

  16. The Potential of Renewable Energy Sources in Latvia

    Science.gov (United States)

    Sakipova, S.; Jakovics, A.; Gendelis, S.

    2016-02-01

    The article discusses some aspects of the use of renewable energy sources in the climatic conditions prevailing in most of the territory of Latvia, with relatively low wind speeds and a small number of sunny days a year. The paper gives a brief description of the measurement equipment and technology to determine the parameters of the outer air; the results of the measurements are also analysed. On the basis of the data obtained during the last two years at the meteorological station at the Botanical Garden of the University of Latvia, the energy potential of solar radiation and wind was estimated. The values of the possible and the actual amount of produced energy were determined.

  17. On the potential energy landscape of supercooled liquids and glasses

    DEFF Research Database (Denmark)

    Rodney, D.; Schrøder, Thomas

    2011-01-01

    The activation-relaxation technique (ART), a saddle-point search method, is applied to determine the potential energy landscape around supercooled and glassy configurations of a three-dimensional binary Lennard-Jones system. We show a strong relation between the distribution of activation energies...... around a given glassy configuration and its history, in particular, the cooling rate used to produce the glass and whether or not the glass was plastically deformed prior to sampling. We also compare the thermally activated transitions found by ART around a supercooled configuration with the succession...... of transitions undergone by the same supercooled liquid during a time trajectory simulated by molecular dynamics. We find that ART is biased towards more heterogeneous transitions with higher activation energies and more broken bonds than the MD simulation....

  18. Directory of Energy Information Administration models 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-07-01

    This directory revises and updates the Directory of Energy Information Administration Models 1995, DOE/EIA-0293(95), Energy Information Administration (EIA), U.S. Department of Energy, July 1995. Four models have been deleted in this directory as they are no longer being used: (1) Market Penetration Model for Ground-Water Heat Pump Systems (MPGWHP); (2) Market Penetration Model for Residential Rooftop PV Systems (MPRESPV-PC); (3) Market Penetration Model for Active and Passive Solar Technologies (MPSOLARPC); and (4) Revenue Requirements Modeling System (RRMS).

  19. Electronic structure, molecular bonding and potential energy surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Ruedenberg, K. [Ames Laboratory, IA (United States)

    1993-12-01

    By virtue of the universal validity of the generalized Born-Oppenheimer separation, potential energy surfaces (PES`) represent the central conceptual as well as quantitative entities of chemical physics and provide the basis for the understanding of most physicochemical phenomena in many diverse fields. The research in this group deals with the elucidation of general properties of PES` as well as with the quantitative determination of PES` for concrete systems, in particular pertaining to reactions involving carbon, oxygen, nitrogen and hydrogen molecules.

  20. Modeling Malaysia's Energy System: Some Preliminary Results

    Directory of Open Access Journals (Sweden)

    Ahmad M. Yusof

    2011-01-01

    Full Text Available Problem statement: The current dynamic and fragile world energy environment necessitates the development of new energy model that solely caters to analyze Malaysia’s energy scenarios. Approach: The model is a network flow model that traces the flow of energy carriers from its sources (import and mining through some conversion and transformation processes for the production of energy products to final destinations (energy demand sectors. The integration to the economic sectors is done exogeneously by specifying the annual sectoral energy demand levels. The model in turn optimizes the energy variables for a specified objective function to meet those demands. Results: By minimizing the inter temporal petroleum product imports for the crude oil system the annual extraction level of Tapis blend is projected at 579600 barrels per day. The aggregate demand for petroleum products is projected to grow at 2.1% year-1 while motor gasoline and diesel constitute 42 and 38% of the petroleum products demands mix respectively over the 5 year planning period. Petroleum products import is expected to grow at 6.0% year-1. Conclusion: The preliminary results indicate that the model performs as expected. Thus other types of energy carriers such as natural gas, coal and biomass will be added to the energy system for the overall development of Malaysia energy model.

  1. 基于超效率DEA模型的中国各地区钢铁行业能源效率及节能减排潜力分析%ANALYSIS OF ENERGY EFFICIENCY AND ENERGY-SAVING AND EMISSION-REDUCTION POTENTIAL OF STEEL INDUSTRY IN VARIOUS REGIONS OF CHINA BASED ON SUPER-EFFICIENCY DEA MODEL

    Institute of Scientific and Technical Information of China (English)

    韩一杰; 刘秀丽

    2011-01-01

    DEA方法对具有多投入和多产出指标的各个DMU之间的相对效率评价具有独特优势.首先应用超效率DEA模型对2005-2007年间中国各地区钢铁行业的全要素能源效率作出评价,并计算了此间中国各地区钢铁行业的节能减排潜力;然后利用Malmquist效率指数对钢铁行业能源利用效率的变动进行动态分析;最后应用Tobit回归模型对影响钢铁行业节能减排的因素进行了多元分析.%DEA has the unique advantage to evaluate the relative efficiency of different DMUs with more than one input indexes and output indexes. Firstly, this paper used Super-Efficiency DEA model to evaluate the total-factor energy efficiency and compute the Energy-Saving and Emission-Reduction Potential of steel industry in various regions of China during 2005-2007. Then we analyzed the variation of energy efficiency of steel industry dynamically using Malmquist index. Finally we analyzed the factors influencing Energy-Saving and Emission-Reduction of steel industry using Tobit regression analysis model.

  2. Binding energies and modelling of nuclei in semiclassical simulations

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Garcia, M. Angeles [Departamento de Fisica Fundamental and Instituto Universitario de Fisica Fundamental y Matematicas, IUFFyM, Universidad de Salamanca, Plaza de la Merced s/n 37008 Salamanca (Spain)], E-mail: mperezga@usal.es; Tsushima, K. [Departamento de Fisica Fundamental and Instituto Universitario de Fisica Fundamental y Matematicas, IUFFyM, Universidad de Salamanca, Plaza de la Merced s/n 37008 Salamanca (Spain)], E-mail: tsushima@usal.es; Valcarce, A. [Departamento de Fisica Fundamental and Instituto Universitario de Fisica Fundamental y Matematicas, IUFFyM, Universidad de Salamanca, Plaza de la Merced s/n 37008 Salamanca (Spain)], E-mail: valcarce@usal.es

    2008-03-06

    We study the binding energies of spin-isospin saturated nuclei with nucleon number 8{<=}A{<=}100 in semiclassical Monte Carlo many-body simulations. The model Hamiltonian consists of (i) nucleon kinetic energy, (ii) a nucleon-nucleon interaction potential, and (iii) an effective Pauli potential which depends on density. The basic ingredients of the nucleon-nucleon potential are a short-range repulsion, and a medium-range attraction. Our results demonstrate that one can always expect to obtain the empirical binding energies for a set of nuclei by introducing a proper density dependent Pauli potential in terms of a single variable, the nucleon number, A. The present work shows that in the suggested procedure there is a delicate counterbalance of kinetic and potential energetic contributions allowing a good reproduction of the experimental nuclear binding energies. This type of calculations may be of interest in further reproduction of other properties of nuclei such as radii and also exotic nuclei.

  3. Numerical Modeling of a Wave Energy Point Absorber

    DEFF Research Database (Denmark)

    Hernandez, Lorenzo Banos; Frigaard, Peter; Kirkegaard, Poul Henning

    2009-01-01

    The present study deals with numerical modelling of the Wave Star Energy WSE device. Hereby, linear potential theory is applied via a BEM code on the wave hydrodynamics exciting the floaters. Time and frequency domain solutions of the floater response are determined for regular and irregular seas....... Furthermore, these results are used to estimate the power and the energy absorbed by a single oscillating floater. Finally, a latching control strategy is analysed in open-loop configuration for energy maximization....

  4. A high-resolution assessment of wind and wave energy potentials in the Red Sea

    KAUST Repository

    Langodan, Sabique

    2016-08-24

    This study presents an assessment of the potential for harvesting wind and wave energy from the Red Sea based on an 18-year high-resolution regional atmospheric reanalysis recently generated using the Advanced Weather Research Forecasting model. This model was initialized with ERA-Interim global data and the Red Sea reanalysis was generated using a cyclic three-dimensional variational approach assimilating available data in the region. The wave hindcast was generated using WAVEWATCH III on a 5 km resolution grid, forced by the Red Sea reanalysis surface winds. The wind and wave products were validated against data from buoys, scatterometers and altimeters. Our analysis suggests that the distribution of wind and wave energy in the Red Sea is inhomogeneous and is concentrated in specific areas, characterized by various meteorological conditions including weather fronts, mesoscale vortices, land and sea breezes and mountain jets. A detailed analysis of wind and wave energy variation was performed at three hotspots representing the northern, central and southern parts of the Red Sea. Although there are potential sites for harvesting wind energy from the Red Sea, there are no potential sites for harvesting wave energy because wave energy in the Red Sea is not strong enough for currently available wave energy converters. Wave energy should not be completely ignored, however, at least from the perspective of hybrid wind-wave projects. (C) 2016 Elsevier Ltd. All rights reserved.

  5. Electromagnetic potentials basis for energy density and power flux

    Science.gov (United States)

    Puthoff, H. E.

    2016-09-01

    In rounding out the education of students in advanced courses in applied electromagnetics it is incumbent on us as mentors to raise issues that encourage appreciation of certain subtle aspects that are often overlooked during first exposure to the field. One of these has to do with the interplay between fields and potentials, with the latter often seen as just a convenient mathematical artifice useful in solving Maxwell’s equations. Nonetheless, to those practiced in application it is well understood that various alternatives in the use of fields and potentials are available within electromagnetic (EM) theory for the definitions of energy density, momentum transfer, EM stress-energy tensor, and so forth. Although the various options are all compatible with the basic equations of electrodynamics (e.g., Maxwell’s equations, Lorentz force law, gauge invariance), nonetheless certain alternative formulations lend themselves to being seen as preferable to others with regard to the transparency of their application to physical problems of interest. Here we argue for the transparency of an energy density/power flux option based on the EM potentials alone.

  6. Bohm's quantum potential as an internal energy

    Energy Technology Data Exchange (ETDEWEB)

    Dennis, Glen, E-mail: gdennis502@gmail.com [TPRU, Birkbeck College, University of London, London, WC1E 7HX (United Kingdom); Gosson, Maurice A. de, E-mail: maurice.de.gosson@univie.ac.at [University of Vienna, Faculty of Mathematics, NuHAG, Oskar-Morgenstern-Platz 1, 1090 Vienna (Austria); Hiley, Basil J., E-mail: b.hiley@bbk.ac.uk [TPRU, Birkbeck College, University of London, London, WC1E 7HX (United Kingdom)

    2015-06-26

    Highlights: • The quantum potential is seen as internal energy associated with a phase space region. • Fermi's trick shows that Bohm's particle is an extended structure in phase space. • We associate Bohm's quantum potential with a context-dependent energy redistribution. • A physically motivated derivation of Schrodinger's equation is provided. • We show the Fermi set associated with a 3-D coherent state contains a quantum blob. - Abstract: We pursue our discussion of Fermi's surface initiated by Dennis, de Gosson and Hiley and show that Bohm's quantum potential can be viewed as an internal energy of a quantum system, giving further insight into its role in stationary states. This implies that the ‘particle’ referred to in Bohm's theory is not a classical point-like object but rather has an extended structure in phase space which can be linked to the notion of a symplectic capacity, a topological feature of the underlying symplectic geometry. This structure provides us with a new, physically motivated derivation of Schrödinger's equation provided we interpret Gleason's theorem as a derivation of the Born rule from fundamental assumptions about quantum probabilities.

  7. Potential energy surface and rovibrational energy levels of the H2-CS van der Waals complex.

    Science.gov (United States)

    Denis-Alpizar, Otoniel; Stoecklin, Thierry; Halvick, Philippe; Dubernet, Marie-Lise; Marinakis, Sarantos

    2012-12-21

    Owing to its large dipole, astrophysicists use carbon monosulfide (CS) as a tracer of molecular gas in the interstellar medium, often in regions where H(2) is the most abundant collider. Predictions of the rovibrational energy levels of the weakly bound complex CS-H(2) (not yet observed) and also of rate coefficients for rotational transitions of CS in collision with H(2) should help to interpret the observed spectra. This paper deals with the first goal, i.e., the calculation of the rovibrational energy levels. A new four-dimensional intermolecular potential energy surface for the H(2)-CS complex is presented. Ab initio potential energy calculations were carried out at the coupled-cluster level with single and double excitations and a perturbative treatment of triple excitations, using a quadruple-zeta basis set and midbond functions. The potential energy surface was obtained by an analytic fit of the ab initio data. The equilibrium structure of the H(2)-CS complex is found to be linear with the carbon pointing toward H(2) at the intermolecular separation of 8.6 a(o). The corresponding well depth is -173 cm(-1). The potential was used to calculate the rovibrational energy levels of the para-H(2)-CS and ortho-H(2)-CS complexes. The present work provides the first theoretical predictions of these levels. The calculated dissociation energies are found to be 35.9 cm(-1) and 49.9 cm(-1), respectively, for the para and ortho complexes. The second virial coefficient for the H(2)-CS pair has also been calculated for a large range of temperature. These results could be used to assign future experimental spectra and to check the accuracy of the potential energy surface.

  8. Energy balance of chosen crops and their potential to saturate energy consumption in Slovakia

    Directory of Open Access Journals (Sweden)

    Katarína Hrčková

    2016-06-01

    Full Text Available The aim of the present work was to assess and compare energy inputs and outputs of various crop managements in 2011–2012. Two main crops on arable land and three permanent grasslands were investigated. Silage maize (Zea mays L. and winter wheat (Triticum aestivum L. were grown on lowland, whilst two semi-natural grasslands and grassland infested by tufted hair-grass (Deschampsia caespitose (L. P. Beauv were located in mountainous regions of Slovakia. In these crops and grasslands the dry matter yield was measured and subsequently the supplementary energy, energy gain and unifying energy value – tonne of oil equivalent (TOE – were calculated. Silage maize with 233.37 GJ*ha-1 has provided the highest energy gain. In the group of grasslands, grassland infested by tufted hair-grass has offered the highest energy gain (59.77 GJ*ha-1. And this grassland had the lowest requirement on the supplementary energy (3.66 GJ*ha-1, contrary to silage maize with highest one (12.37 GJ*ha-1. The total energy potential of the crop biomasses was confronted with energy consumption in Slovakia. Winter wheat has the biggest energy potential, but it could cover only 19.6% and 11.3% total consumption of electricity or natural gas, respectively. Large area of permanent grasslands and their spatial location make them an important energy reservoir for bioenergy production. But, it is not possible to replace all consumed fossil fuels by bioenergy from these tested renewable energy sources.

  9. Optimal schooling formations using a potential flow model

    Science.gov (United States)

    Tchieu, Andrew; Gazzola, Mattia; de Brauer, Alexia; Koumoutsakos, Petros

    2012-11-01

    A self-propelled, two-dimensional, potential flow model for agent-based swimmers is used to examine how fluid coupling affects schooling formation. The potential flow model accounts for fluid-mediated interactions between swimmers. The model is extended to include individual agent actions by means of modifying the circulation of each swimmer. A reinforcement algorithm is applied to allow the swimmers to learn how to school in specified lattice formations. Lastly, schooling lattice configurations are optimized by combining reinforcement learning and evolutionary optimization to minimize total control effort and energy expenditure.

  10. General business model patterns for Local Energy Management concepts

    Directory of Open Access Journals (Sweden)

    Emanuele eFacchinetti

    2016-03-01

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

  11. Potential Models for Radiative Rare B Decays

    CERN Document Server

    Ahmad, S

    2002-01-01

    We compute the branching ratios for the radiative rare decays of B into K-Meson states and compare them to the experimentally determined branching ratio for inclusive decay b -> s gamma using non relativistic quark model, and form factor definitions consistent with HQET covariant trace formalism. Such calculations necessarily involve a potential model. In order to test the sensitivity of calculations to potential models we have used three different potentials, namely linear potential, screening confining potential and heavy quark potential as it stands in QCD.We find the branching ratios relative to the inclusive b ->s gamma decay to be (16.07\\pm 5.2)% for B -> K^* (892)gamma and (7.25\\pm 3.2)% for B -> K_2^* (1430)gamma for linear potential. In the case of the screening confining potential these values are (19.75\\pm 5.3)% and (4.74\\pm 1.2)% while those for the heavy quark potential are (11.18\\pm 4.6)% and (5.09\\pm 2.7)% respectively. All these values are consistent with the corresponding present CLEO experim...

  12. Wind Energy Potential: Current representation and projections for the European domain

    Science.gov (United States)

    Davy, Richard; Gnatiuk, Natalia; Bobylev, Leonid; Pettersson, Lasse

    2016-04-01

    We have used the publically available CORDEX datasets to quantify the ability of a current regional climate model (SMHI-RCA4) to simulate the wind energy potential in the Black sea region using 5 different global climate models for the boundary conditions. The regional climate model results are compared to the ERA-Interim reanalyses over a common period, 1979-2005, and we use Taylor plots to demonstrate the effect of different global climate models on the regional climate simulations. Wind energy potential is calculated from the daily hub-height (120 m) wind speeds by extrapolating the available 10 m wind speeds using a power-law wind profile approximation. In general we find that the regional climate model produces stronger surface winds over the Black Sea region as compared to the ERA-Interim reanalysis, which we relate to the difference in model resolution. We also assess the projected changes to the wind energy potential in the CORDEX EUR-11 region from the current period to the near future (2021-2050), and to the late 21st century (2061-2090). We use a single model ensemble approach to assess the robustness of the projected changes, depending upon the choice of global climate model used for the boundary conditions. To understand the context of the changes in wind energy potential in the region, we include the changing climatology of the upper level (850 hPa) winds over these periods. This work was supported by the EU FP7 Project, Grant agreement No.: 287844. "Towards COast to COast NETworks of marine protected areas (from the shore to the high and deep sea), coupled with sea-based wind energy potential (CoCoNet)".

  13. GIS Assessment of Wind Energy Potential in California and Florida

    Science.gov (United States)

    Snow, R. K.; Snow, M. M.

    2008-05-01

    Energy efficiency coupled with renewable energy technologies can provide most of the U.S. carbon emissions reductions needed to contain atmospheric carbon concentrations at 450-500 parts per million, considered by many to be a tipping point in mitigating climate change. Among the leaders in the alternative energy sector is wind power, which is now one of the largest sources of new power generation in the U.S. creating jobs and revenue for rural communities while powering our economy with an emissions-free source of energy. In 2006, wind turbines capable of generating more than 2,400 megawatts of electricity were installed in the U.S. and by 2007 this number had risen to 3,000 megawatts. The U.S. generated 31 billion kilowatt-hours of wind power in 2007, which is enough electricity to power the equivalent of nearly 3 million average homes. It is estimated that generating the same amount of electricity would require burning 16 million tons of coal or 50 million barrels of oil. This study examines the wind power potential of sites near populated areas in Florida and California to determine the practicability of installing wind turbines at these locations. A GIS was developed in order to conduct a spatial analysis of these sites based on mean annual wind speed measured in meters per second and wind power density ratings measured in watts per square meter. The analysis indicates that coastal areas of Cocoa Beach, Key West, Hollywood, and West Palm Beach, respectively, possess the greatest potential for wind energy in Florida with mean annual wind speeds of 4.9 m/s and average wind power density ratings of 171 w/m2 peaking at Cocoa Beach followed by wind speeds of 4.64 m/s and wind power ratings of 115 w/m2 at Key West. California wind energy potential is even greater than that of Florida with Fairfield exhibiting mean annual wind speeds of 5.9 m/s and average wind power density ratings of 327 w/m2 followed by the Mojave and Palmdale areas with mean annual wind speeds of

  14. Directory of Energy Information Administration Models 1994

    Energy Technology Data Exchange (ETDEWEB)

    1994-07-01

    This directory revises and updates the 1993 directory and includes 15 models of the National Energy Modeling System (NEMS). Three other new models in use by the Energy Information Administration (EIA) have also been included: the Motor Gasoline Market Model (MGMM), Distillate Market Model (DMM), and the Propane Market Model (PPMM). This directory contains descriptions about each model, including title, acronym, purpose, followed by more detailed information on characteristics, uses and requirements. Sources for additional information are identified. Included in this directory are 37 EIA models active as of February 1, 1994.

  15. Power Systems and Energy Storage Modeling for Directed Energy Weapons

    Science.gov (United States)

    2014-06-01

    electron laser kW Kilo-watt LCS Littoral Combat Ship LAWS Laser Weapon System MLD Maritime Laser Demonstration MW Mega -watt NiMH Nickel metal...and various littoral combat ships. Also, an accurate, working model of the capacitor energy bank is being developed and the flywheel model is being

  16. Marine Planning for Potential Wave Energy Facility Placement Amongst a Crowded Sea of Existing Resource Uses

    Science.gov (United States)

    Feist, B. E.; Fuller, E.; Plummer, M. L.

    2016-12-01

    Conversion to renewable energy sources is a logical response to increasing pressure to reduce greenhouse gas emissions. Ocean wave energy is the least developed renewable energy source, despite having the highest energy per unit area. While many hurdles remain in developing wave energy, assessing potential conflicts and evaluating tradeoffs with existing uses is essential. Marine planning encompasses a broad array of activities that take place in and affect large marine ecosystems, making it an ideal tool for evaluating wave energy resource use conflicts. In this study, we focus on the potential conflicts between wave energy conversion (WEC) facilities and existing marine uses in the context of marine planning, within the California Current Large Marine Ecosystem. First, we evaluated wave energy facility development using the Wave Energy Model (WEM) of the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) toolkit. Second, we ran spatial analyses on model output to identify conflicts with existing marine uses including AIS based vessel traffic, VMS and observer based measures of commercial fishing effort, and marine conservation areas. We found that regions with the highest wave energy potential were distant from major cities and that infrastructure limitations (cable landing sites) restrict integration with existing power grids. We identified multiple spatial conflicts with existing marine uses; especially shipping vessels and various commercial fishing fleets, and overlap with marine conservation areas varied by conservation designation. While wave energy generation facilities may be economically viable in the California Current, this viability must be considered within the context of the costs associated with conflicts that arise with existing marine uses. Our analyses can be used to better inform placement of WEC devices (as well as other types of renewable energy facilities) in the context of marine planning by accounting for economic tradeoffs

  17. The Folding Deuteron Optical Model Potentials

    CERN Document Server

    Li, Xiaohua; Cai, Chonghai

    2008-01-01

    For 52 target nuclei with deuteron as projectile, we calculate the reaction cross sections and elastic scattering angular distributions, as well as the $\\chi^2$ values for 11 kinds of deuteron optical model potentials: our global deuteron optical potentials and 10 folding optical potentials calculated with 2 phenomenological global nucleon optical potentials given by Koning \\textit{et al}(KD) and by Varner\\textit{et al}(CH89), and 8 microscopic nucleon optical potentials with the generalized Skyrme force parameters(GS1-6) and modified Skyrme force parameters(SKa, SKb). We find that for constructing the folding deuteron optical potential, both SKa and SKb are the best Skyrme force parameters of the microscopic nucleon optical potential proposed by Q. Shen \\textit{et al}.

  18. Global and Regional Future Potential for Energy from Municipal Solid Waste

    Science.gov (United States)

    Gregg, J. S.; Smith, S. J.

    2008-12-01

    Municipal Solid Waste (MSW) is a low-cost form of alternative energy with a large potential for future expansion. MSW is already collected and aggregated at population centers where energy demands are high. In addition, it is non-seasonal, and using MSW as an energy source reduces land demand for waste disposal sites in urban areas where land pressures are high. Across the world, the MSW generation rate and its composition vary greatly, but detailed historical data on MSW are not well archived for most of the world. In this study, material flows into the MSW stream are estimated by analyzing production and trade statistics of food, wood, and paper. A life cycle analysis for consumption is used to estimate the amount and composition of MSW for all countries of the world. The primary energy available is estimated based on the energy content of the various waste components. The relationship between GDP, population, per capita GDP, and MSW generation is determined via a regression model. The ObjECTS MiniCAM (integrated assessment model) is used to project the demand for waste-to-energy for the next century for different regions of the world under various international climate policy scenarios. MSW is potentially a low net carbon energy source that can displace fossil energy, and as such, demand for waste-to-energy increases under a climate policy that places a price on carbon emissions.

  19. World energy projection system: Model documentation

    Energy Technology Data Exchange (ETDEWEB)

    1992-06-01

    The World Energy Project System (WEPS) is an accounting framework that incorporates projects from independently documented models and assumptions about the future energy intensity of economic activity (ratios of total energy consumption divided by gross domestic product) and about the rate of incremental energy requirements met by hydropower, geothermal, coal, and natural gas to produce projections of world energy consumption published annually by the Energy Information Administration (EIA) in the International Energy Outlook (IEO) (Figure 1). Two independently documented models presented in Figure 1, the Oil Market Simulation (OMS) model and the World Integrated Nuclear Evaluation System (WINES) provide projections of oil and nuclear power consumption published in the IEO. Output from a third independently documented model, and the International Coal Trade Model (ICTM), is not published in the IEO but is used in WEPS as a supply check on projections of world coal consumption produced by WEPS and published in the IEO. A WEPS model of natural gas production documented in this report provides the same type of implicit supply check on the WEPS projections of world natural gas consumption published in the IEO. Two additional models are included in Figure 1, the OPEC Capacity model and the Non-OPEC Oil Production model. These WEPS models provide inputs to the OMS model and are documented in this report.

  20. G-corrected holographic dark energy model

    CERN Document Server

    Malekjani, M

    2013-01-01

    Here we investigate the holographic dark energy model in the framework of FRW cosmology where the Newtonian gravitational constant,$G$, is varying with cosmic time. Using the complementary astronomical data which support the time dependency of $G$, the evolutionary treatment of EoS parameter and energy density of dark energy model are calculated in the presence of time variation of $G$. It has been shown that in this case, the phantom regime can be achieved at the present time. We also calculate the evolution of $G$- corrected deceleration parameter for holographic dark energy model and show that the dependency of $G$ on the comic time can influence on the transition epoch from decelerated expansion to the accelerated phase. Finally we perform the statefinder analysis for $G$- corrected holographic model and show that this model has a shorter distance from the observational point in $s-r$ plane compare with original holographic dark energy model.

  1. Multiple scattering of low energy ions in matter: Influence of energy loss and interaction potential

    Energy Technology Data Exchange (ETDEWEB)

    Mekhtiche, A. [Laboratoire SNIRM, Faculté de Physique, Université des Sciences et de la Technologie Houari Boumediene (USTHB), BP 32 El Alia, Bab Ezzouar, Algiers (Algeria); Faculté des Sciences et de la Technologie, Université Yahia Farès de Médéa (Algeria); Khalal-Kouache, K., E-mail: kkouache@yahoo.fr [Laboratoire SNIRM, Faculté de Physique, Université des Sciences et de la Technologie Houari Boumediene (USTHB), BP 32 El Alia, Bab Ezzouar, Algiers (Algeria)

    2015-07-01

    In this paper, the effect of inelastic energy loss and interaction potential on transmitted ions at low energy is studied. For this purpose, angular distributions of slow He{sup +} ions transmitted through thin Ag films are calculated using the theory of multiple scattering. Thin films (20–50 Å at 2 keV and 50–200 Å at 10 keV) are considered so that the total path length of transmitted ions can be approximated by the value of the target thickness in this calculation. The corresponding values of the relative energy loss ΔE/E are comprised between 0.04 and 0.17. We show that even if low values of the thickness are considered, the total energy loss of ions in the target should be included in the calculation. These calculated angular distributions are also influenced by the potential used to describe the interaction between the incident ion and the target atom.

  2. Modeling of renewable hybrid energy sources

    Directory of Open Access Journals (Sweden)

    Dumitru Cristian Dragos

    2009-12-01

    Full Text Available Recent developments and trends in the electric power consumption indicate an increasing use of renewable energy. Renewable energy technologies offer the promise of clean, abundant energy gathered from self-renewing resources such as the sun, wind, earth and plants. Virtually all regions of the world have renewable resources of one type or another. By this point of view studies on renewable energies focuses more and more attention. The present paper intends to present different mathematical models related to different types of renewable energy sources such as: solar energy and wind energy. It is also presented the validation and adaptation of such models to hybrid systems working in geographical and meteorological conditions specific to central part of Transylvania region. The conclusions based on validation of such models are also shown.

  3. Statefinder parameters in two dark energy models

    CERN Document Server

    Panotopoulos, Grigoris

    2007-01-01

    The statefinder parameters ($r,s$) in two dark energy models are studied. In the first, we discuss in four-dimensional General Relativity a two fluid model, in which dark energy and dark matter are allowed to interact with each other. In the second model, we consider the DGP brane model generalized by taking a possible energy exchange between the brane and the bulk into account. We determine the values of the statefinder parameters that correspond to the unique attractor of the system at hand. Furthermore, we produce plots in which we show $s,r$ as functions of red-shift, and the ($s-r$) plane for each model.

  4. An ab initio potential energy surface and vibrational energy levels of HXeBr

    Institute of Scientific and Technical Information of China (English)

    Zheng Guo Huang; En Cui Yang; Dai Qian Xie

    2008-01-01

    A three-dimensional global potential energy surface for the electronic ground state of HXeBr molecule is constructed from morethan 4200 ab initio points. These points are generated using an internally contracted multi-reference configuration interactionmethod with the Davidson correction (icMRCI + Q) and large basis sets. The stabilities and dissociation barriers are identified fromthe potential energy surfaces. The three-body dissociation channel is found to be the dominate dissociation channel for HXeBr.Based on the obtained potentials, low-lying vibrational energy levels of HXeBr calculated using the Lanczos algorithm is found tobe in good agreement with the available experimental band origins.2008 Zheng Guo Huang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

  5. Energy deposition by heavy ions: additivity of kinetic and potential energy contributions in hillock formation on CaF2.

    Science.gov (United States)

    Wang, Y Y; Grygiel, C; Dufour, C; Sun, J R; Wang, Z G; Zhao, Y T; Xiao, G Q; Cheng, R; Zhou, X M; Ren, J R; Liu, S D; Lei, Y; Sun, Y B; Ritter, R; Gruber, E; Cassimi, A; Monnet, I; Bouffard, S; Aumayr, F; Toulemonde, M

    2014-07-18

    Modification of surface and bulk properties of solids by irradiation with ion beams is a widely used technique with many applications in material science. In this study, we show that nano-hillocks on CaF2 crystal surfaces can be formed by individual impact of medium energy (3 and 5 MeV) highly charged ions (Xe(22+) to Xe(30+)) as well as swift (kinetic energies between 12 and 58 MeV) heavy xenon ions. For very slow highly charged ions the appearance of hillocks is known to be linked to a threshold in potential energy (Ep) while for swift heavy ions a minimum electronic energy loss per unit length (Se) is necessary. With our results we bridge the gap between these two extreme cases and demonstrate, that with increasing energy deposition via Se the Ep-threshold for hillock production can be lowered substantially. Surprisingly, both mechanisms of energy deposition in the target surface seem to contribute in an additive way, which can be visualized in a phase diagram. We show that the inelastic thermal spike model, originally developed to describe such material modifications for swift heavy ions, can be extended to the case where both kinetic and potential energies are deposited into the surface.

  6. A new gravitational model for dark energy

    Institute of Scientific and Technical Information of China (English)

    HUANG Chao-Guang; ZHANG Hai-Qing; GUO Han-Ying

    2008-01-01

    A new gravitational model for dark energy is presented based on the model of de Sitter gauge theory of gravity.In the model,in addition to the cosmological constant,the homogeneous and isotropic torsion and its coupling with curvature play an important role for dark energy.The model may supply the universe with a natural transit from decelerating expansion to accelerating expansion.

  7. Proton-Proton On Shell Optical Potential at High Energies and the Grayness Effect

    CERN Document Server

    Arriola, Enrique Ruiz

    2016-01-01

    We analyze the usefulness of the optical potential as suggested by the double spectral Mandelstam representation at very high energies, such as in the proton-proton scattering at ISR and the LHC. Its particular meaning regarding the interpretation of the scattering data up to the maximum available measured energies is discussed. Our analysis suggests the onset of gray nucleons at the LHC and precludes convolution models at the attometer scale.

  8. Mineral potential mapping with mathematical geological models

    NARCIS (Netherlands)

    Porwal, A.K.

    2006-01-01

    Mathematical geological models are being increasingly used by natural resources delineation and planning agencies for mapping areas of mineral potential in order to optimize land use in accordance with socio-economic needs of the society. However, a key problem in spatial-mathematical-model-based mi

  9. Mineral potential mapping with mathematical geological models

    NARCIS (Netherlands)

    Porwal, A.K.

    2006-01-01

    Mathematical geological models are being increasingly used by natural resources delineation and planning agencies for mapping areas of mineral potential in order to optimize land use in accordance with socio-economic needs of the society. However, a key problem in spatial-mathematical-model-based

  10. International Energy Agency Ocean Energy Systems Task 10 Wave Energy Converter Modeling Verification and Validation

    DEFF Research Database (Denmark)

    Wendt, Fabian F.; Yu, Yi-Hsiang; Nielsen, Kim

    2017-01-01

    This is the first joint reference paper for the Ocean Energy Systems (OES) Task 10 Wave Energy Converter modeling verification and validation group. The group is established under the OES Energy Technology Network program under the International Energy Agency. OES was founded in 2001 and Task 10 ...

  11. Calibrated energy simulations of potential energy savings in actual retail buildings

    Science.gov (United States)

    Alhafi, Zuhaira

    Retail stores are commercial buildings with high energy consumption due to their typically large volumes and long hours of operation. This dissertation assesses heating, ventilating and air conditioning saving strategies based on energy simulations with input parameters from actual retail buildings. The dissertation hypothesis is that "Retail store buildings will save a significant amount of energy by (1) modifying ventilation rates, and/or (2) resetting set point temperatures. These strategies have shown to be beneficial in previous studies. As presented in the literature review, potential energy savings ranged from 0.5% to 30% without compromising indoor thermal comfort and indoor air quality. The retail store buildings can be ventilated at rates significantly lower than rates called for in the ASHRAE Standard 62.1-2010 while maintaining acceptable indoor air quality. Therefore, two dissertation objectives are addressed: (1) Investigate opportunities to reduce ventilation rates that do not compromise indoor air quality in retail stores located in Central Pennsylvania, (2) Investigate opportunities to increase (in summer) and decrease (in winter) set point temperatures that do not compromise thermal comfort. This study conducted experimental measurements of ventilation rates required to maintain acceptable air quality and indoor environmental conditions requirements for two retail stores using ASHRAE Standard 62.1_2012. More specifically, among other parameters, occupancy density, indoor and outdoor pollutant concentrations, and indoor temperatures were measured continuously for one week interval. One of these retail stores were tested four times for a yearlong time period. Pollutants monitored were formaldehyde, carbon dioxide, particle size distributions and concentrations, as well as total volatile organic compounds. As a part of the base protocol, the number of occupants in each store was hourly counted during the test, and the results reveal that the occupant

  12. Ringkøbing-Skjern energy atlas for analysis of heat saving potentials in building stock

    DEFF Research Database (Denmark)

    Petrovic, Stefan; Karlsson, Kenneth Bernard

    2016-01-01

    potential can be harvested by insulating floors, while majority of heat saving potential cheaper than 2 DKK/kWh can be utilised by insulating floors and installing mechanical ventilation systems. After heat savings and heat supply options are compared from a private-economic perspective, it is concluded...... such drastic change of municipality's energy system. For that purpose, GIS-based Ringkøbing-Skjern Energy Atlas has been developed. The present paper utilises Ringkøbing-Skjern Energy Atlas together with the Heating Model to calculate potentials and costs of heat saving measures.The results show...... that the reduction of heating demand by 25% and 35% can be achieved at the annuitized full cost lower than 1.7 and 2 DKK/kWh, respectively. The results also show that significant heat saving potential lies in farmhouses and detached houses as well as in buildings built before 1950. Over 75% of very cheap heat saving...

  13. Correlation energy and dispersion interaction in the ab initio potential energy curve of the neon dimer.

    Science.gov (United States)

    Bytautas, Laimutis; Ruedenberg, Klaus

    2008-06-01

    A close approximation to the empirical potential energy curve of the neon dimer is obtained by coupled-cluster singles plus doubles plus noniterative triples calculations by using nonaugmented correlation-consistent basis sets without counterpoise corrections and complementing them by three-term extrapolations to the complete basis set limit. The potential energy is resolved into a self-consistent-field Hartree-Fock contribution and a correlation contribution. The latter is shown to decay in the long-range region in accordance with the empirical dispersion expansion.

  14. Feet on the potential energy surface, head in the pi clouds

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Quentin [Iowa State Univ., Ames, IA (United States)

    2011-01-01

    This work presents explorations of the potential energy surface of clusters of atoms and of the interactions between molecules. First, structures of small aluminum clusters are examined and classified as ground states, transition states, or higher-order saddle points. Subsequently, the focus shifts to dispersion-dominated π-π interactions when the potential energy surfaces of benzene, substituted benzene, and pyridine dimers are explored. Because DNA nucleotide bases can be thought of as substituted heterocycles, a natural extension of the substituted benzene and pyridine investigations is to model paired nucleotide bases. Finally, the success of the dispersion studies inspires the development of an extension to the computational method used, which will enable the dispersion energy to be modeled – and the potential energy surface explored – in additional chemical systems. The effective fragment potential (EFP) method is described, as well as various quantum mechanical methods. An ab inito quantum mechanical study of 13-atom aluminum clusters is described. EFP studies of aromatic dimers are reported in which dispersion energy makes a significant contribution to the attraction between monomers. Theory and code development toward a means of computing dispersion energy in mixed ab inito-EFP systems are described.

  15. Potential for energy conservation in the cement industry

    Energy Technology Data Exchange (ETDEWEB)

    Garrett-Price, B.A.

    1985-02-01

    This report assesses the potential for energy conservation in the cement industry. Energy consumption per ton of cement decreased 20% between 1972 and 1982. During this same period, the cement industry became heavily dependent on coal and coke as its primary fuel source. Although the energy consumed per ton of cement has declined markedly in the past ten years, the industry still uses more than three and a half times the fuel that is theoretically required to produce a ton of clinker. Improving kiln thermal efficiency offers the greatest opportunity for saving fuel. Improving the efficiency of finish grinding offers the greatest potential for reducing electricity use. Technologies are currently available to the cement industry to reduce its average fuel consumption per ton by product by as much as 40% and its electricity consumption per ton by about 10%. The major impediment to adopting these technologies is the cement industry's lack of capital as a result of low or no profits in recent years.

  16. Intermolecular potential energy surface and thermophysical properties of ethylene oxide

    Energy Technology Data Exchange (ETDEWEB)

    Crusius, Johann-Philipp, E-mail: johann-philipp.crusius@uni-rostock.de; Hassel, Egon [Lehrstuhl für Technische Thermodynamik, Universität Rostock, 18059 Rostock (Germany); Hellmann, Robert; Bich, Eckard [Institut für Chemie, Universität Rostock, 18059 Rostock (Germany)

    2014-10-28

    A six-dimensional potential energy hypersurface (PES) for two interacting rigid ethylene oxide (C{sub 2}H{sub 4}O) molecules was determined from high-level quantum-chemical ab initio calculations. The counterpoise-corrected supermolecular approach at the MP2 and CCSD(T) levels of theory was utilized to determine interaction energies for 10178 configurations of two molecules. An analytical site-site potential function with 19 sites per ethylene oxide molecule was fitted to the interaction energies and fine tuned to agree with data for the second acoustic virial coefficient from accurate speed of sound measurements. The PES was validated by computing the second virial coefficient, shear viscosity, and thermal conductivity. The values of these properties are substantiated by the best experimental data as they tend to fall within the uncertainty intervals and also obey the experimental temperature functions, except for viscosity, where experimental data are insufficient. Due to the lack of reliable data, especially for the transport properties, our calculated values are currently the most accurate estimates for these properties of ethylene oxide.

  17. Energy and Uncertainty: Models and Algorithms for Complex Energy Systems

    OpenAIRE

    2014-01-01

    The problem of controlling energy systems (generation, transmission, storage, investment) introduces a number of optimization problems which need to be solved in the presence of different types of uncertainty. We highlight several of these applications, using a simple energy storage problem as a case application. Using this setting, we describe a modeling framework based around five fundamental dimensions which is more natural than the standard canonical form widely used in the reinforcement ...

  18. Energy strategy and mitigation potential in energy sector of the Russian federation

    Energy Technology Data Exchange (ETDEWEB)

    Yakovlev, A.F.; Petrov, V.N.; Chupyatov, V.P.

    1996-12-31

    This paper describes the mitigation potential in the Russian energy sector and presents CO{sub 2} - emission scenarios. Based on the Russian energy strategy, energy conservation potential has been estimated and three groups of energy conservation measures have been pointed out. Taking into account the economic development scenarios and the scenarios of energy consumption and energy conservation, future CO{sub 2} emission scenarios for 2000 and 2010 have been prepared. Some important characteristics of these scenarios have been presented and discussed. For the period 2000-2010 annual growth rates for CO{sub 2} emission in the Russian energy sector will not exceed 0.9-1.3 %, and emission levels in 2000 make up - 75-78 %, and in 2010 - 81-88 % of the 1990 level. For the probable scenario the CO{sub 2} emission reducing will make up about 6% and 25% (for the optimistic scenario about 16% and 31%) of CO{sub 2} emission for reference scenario in 2000 and 2010 respectively. Additional CO{sub 2} emission reducing (3-5% of domestic CO{sub 2} emission) will result from increasing share of natural gas consumption.

  19. The underestimated potential of solar energy to mitigate climate change

    Science.gov (United States)

    Creutzig, Felix; Agoston, Peter; Goldschmidt, Jan Christoph; Luderer, Gunnar; Nemet, Gregory; Pietzcker, Robert C.

    2017-09-01

    The Intergovernmental Panel on Climate Change's fifth assessment report emphasizes the importance of bioenergy and carbon capture and storage for achieving climate goals, but it does not identify solar energy as a strategically important technology option. That is surprising given the strong growth, large resource, and low environmental footprint of photovoltaics (PV). Here we explore how models have consistently underestimated PV deployment and identify the reasons for underlying bias in models. Our analysis reveals that rapid technological learning and technology-specific policy support were crucial to PV deployment in the past, but that future success will depend on adequate financing instruments and the management of system integration. We propose that with coordinated advances in multiple components of the energy system, PV could supply 30-50% of electricity in competitive markets.

  20. Modeling Energy and Development : An Evaluation of Models and Concepts

    NARCIS (Netherlands)

    Ruijven, Bas van; Urban, Frauke; Benders, René M.J.; Moll, Henri C.; Sluijs, Jeroen P. van der; Vries, Bert de; Vuuren, Detlef P. van

    2008-01-01

    Most global energy models are developed by institutes from developed countries focusing primarily oil issues that are important in industrialized countries. Evaluation of the results for Asia of the IPCC/SRES models shows that broad concepts of energy and development. the energy ladder and the envir

  1. Crustal Gravitational Potential Energy Change and Subduction Earthquakes

    Science.gov (United States)

    Zhu, P. P.

    2017-05-01

    Crustal gravitational potential energy (GPE) change induced by earthquakes is an important subject in geophysics and seismology. For the past forty years the research on this subject stayed in the stage of qualitative estimate. In recent few years the 3D dynamic faulting theory provided a quantitative solution of this subject. The theory deduced a quantitative calculating formula for the crustal GPE change using the mathematic method of tensor analysis under the principal stresses system. This formula contains only the vertical principal stress, rupture area, slip, dip, and rake; it does not include the horizontal principal stresses. It is just involved in simple mathematical operations and does not hold complicated surface or volume integrals. Moreover, the hanging wall vertical moving (up or down) height has a very simple expression containing only slip, dip, and rake. The above results are significant to investigate crustal GPE change. Commonly, the vertical principal stress is related to the gravitational field, substituting the relationship between the vertical principal stress and gravitational force into the above formula yields an alternative formula of crustal GPE change. The alternative formula indicates that even with lack of in situ borehole measured stress data, scientists can still quantitatively calculate crustal GPE change. The 3D dynamic faulting theory can be used for research on continental fault earthquakes; it also can be applied to investigate subduction earthquakes between oceanic and continental plates. Subduction earthquakes hold three types: (a) crust only on the vertical up side of the rupture area; (b) crust and seawater both on the vertical up side of the rupture area; (c) crust only on the vertical up side of the partial rupture area, and crust and seawater both on the vertical up side of the remaining rupture area. For each type we provide its quantitative formula of the crustal GPE change. We also establish a simplified model (called

  2. Evolution of the potential-energy surface of amorphous silicon

    OpenAIRE

    Kallel, Houssem; Mousseau, Normand; Schiettekatte, François

    2010-01-01

    The link between the energy surface of bulk systems and their dynamical properties is generally difficult to establish. Using the activation-relaxation technique (ART nouveau), we follow the change in the barrier distribution of a model of amorphous silicon as a function of the degree of relaxation. We find that while the barrier-height distribution, calculated from the initial minimum, is a unique function that depends only on the level of distribution, the reverse-barrier height distributio...

  3. Theoretical studies of potential energy surfaces and computational methods

    Energy Technology Data Exchange (ETDEWEB)

    Shepard, R. [Argonne National Laboratory, IL (United States)

    1993-12-01

    This project involves the development, implementation, and application of theoretical methods for the calculation and characterization of potential energy surfaces involving molecular species that occur in hydrocarbon combustion. These potential energy surfaces require an accurate and balanced treatment of reactants, intermediates, and products. This difficult challenge is met with general multiconfiguration self-consistent-field (MCSCF) and multireference single- and double-excitation configuration interaction (MRSDCI) methods. In contrast to the more common single-reference electronic structure methods, this approach is capable of describing accurately molecular systems that are highly distorted away from their equilibrium geometries, including reactant, fragment, and transition-state geometries, and of describing regions of the potential surface that are associated with electronic wave functions of widely varying nature. The MCSCF reference wave functions are designed to be sufficiently flexible to describe qualitatively the changes in the electronic structure over the broad range of geometries of interest. The necessary mixing of ionic, covalent, and Rydberg contributions, along with the appropriate treatment of the different electron-spin components (e.g. closed shell, high-spin open-shell, low-spin open shell, radical, diradical, etc.) of the wave functions, are treated correctly at this level. Further treatment of electron correlation effects is included using large scale multireference CI wave functions, particularly including the single and double excitations relative to the MCSCF reference space. This leads to the most flexible and accurate large-scale MRSDCI wave functions that have been used to date in global PES studies.

  4. Potential impacts of nanotechnology on energy transmission applications and needs.

    Energy Technology Data Exchange (ETDEWEB)

    Elcock, D.; Environmental Science Division

    2007-11-30

    The application of nanotechnologies to energy transmission has the potential to significantly impact both the deployed transmission technologies and the need for additional development. This could be a factor in assessing environmental impacts of right-of-way (ROW) development and use. For example, some nanotechnology applications may produce materials (e.g., cables) that are much stronger per unit volume than existing materials, enabling reduced footprints for construction and maintenance of electricity transmission lines. Other applications, such as more efficient lighting, lighter-weight materials for vehicle construction, and smaller batteries having greater storage capacities may reduce the need for long-distance transport of energy, and possibly reduce the need for extensive future ROW development and many attendant environmental impacts. This report introduces the field of nanotechnology, describes some of the ways in which processes and products developed with or incorporating nanomaterials differ from traditional processes and products, and identifies some examples of how nanotechnology may be used to reduce potential ROW impacts. Potential environmental, safety, and health impacts are also discussed.

  5. Potential environmental effects of energy conservation measures in northwest industries

    Energy Technology Data Exchange (ETDEWEB)

    Baechler, M C; Gygi, K F; Hendrickson, P L

    1992-01-01

    The Bonneville Power Administration (Bonneville) has identified 101 plants in the Pacific Northwest that account for 80% of the region's industrial electricity consumption. These plants offer a precise target for a conservation program. PNL determined that most of these 101 plants were represented by 11 major industries. We then reviewed 36 major conservation technologies used in these 11 industrial settings to determine their potential environmental impacts. Energy efficiency technologies designed for industrial use may result in direct or indirect environmental impacts. Effects may result from the production of the conservation measure technology, changes in the working environment due to different energy and material requirements, or changes to waste streams. Industry type, work-place conditions, worker training, and environmental conditions inside and outside the plant are all key variables that may affect environmental outcomes. To address these issues this report has three objectives: Describe potential conservation measures that Bonneville may employ in industrial programs and discuss potential primary impacts. Characterize industrial systems and processes where the measure may be employed and describe general environmental issues associated with each industry type. Review environmental permitting, licensing, and other regulatory actions required for industries and summarize the type of information available from these sources for further analysis.

  6. Photosynthetic free energy transduction. Modelling electrochemical events.

    NARCIS (Netherlands)

    Kooten, van O.

    1988-01-01

    This thesis is concerned with a particular part of the photosynthesis process. This part consists of the light-induced transmembrane electric potential gradient, the electrochemical pH gradient and the subsequent transformation of the energy contained in these gradients into chemical free energy of

  7. Energy Saving Potential by Utilizing Natural Ventilation under Warm Conditions

    DEFF Research Database (Denmark)

    Oropeza-Perez, Ivan; Østergaard, Poul Alberg

    2014-01-01

    The objective of this article is to show the potential of natural ventilation as a passive cooling method within the residential sector of countries which are located in warm conditions using Mexico as a case study. The method is proposed as performing, with a simplified ventilation model, thermal...

  8. Potential for energy savings in old and new auto engines

    Science.gov (United States)

    Reitz, John R.

    1985-11-01

    This paper disucsses the potential for energy savings in the transportation sector through the use of both improved and entirely new automotive engines. Although spark-ignition and diesel internal combustion engines will remain the dominant choices for passenger-car use throughout the rest of this century, improved versions of these engines (lean-burn, low-friction spark-ignition and adiabatic, low-friction diesel engines) could, in the long term, provide a 20-30 percent improvement in fuel economy over what is currently available. The use of new materials, and modifications to both vehicle structure and vehicle transmissions may yield further improvements. Over a longer time frame, the introduction of the high-temperature gas-turbine engine and the use of new synfuels may provide further opportunities for energy conservation.

  9. Stabilized Quasi-Newton Optimization of Noisy Potential Energy Surfaces

    CERN Document Server

    Schaefer, Bastian; Roy, Shantanu; Goedecker, Stefan

    2014-01-01

    Optimizations of atomic positions belong to the most commonly performed tasks in electronic structure calculations. Many simulations like global minimum searches or characterizations of chemical reactions require performing hundreds or thousands of minimizations or saddle computations. To automatize these tasks, optimization algorithms must not only be efficient, but also very reliable. Unfortunately computational noise in forces and energies is inherent to electronic structure codes. This computational noise poses a sever problem to the stability of efficient optimization methods like the limited-memory Broyden-Fletcher-Goldfarb-Shanno algorithm. We here present a technique that allows obtaining significant curvature information of noisy potential energy surfaces. We use this technique to construct both, a stabilized quasi-Newton minimization method and a stabilized quasi-Newton saddle finding approach. We demonstrate with the help of benchmarks that both the minimizer and the saddle finding approach are sup...

  10. Energy expenditure estimates during school physical education: Potential vs. reality?

    Science.gov (United States)

    Kahan, David; McKenzie, Thomas L

    2017-02-01

    Schools are salient locations for addressing the high prevalence of overweight and obesity. Most US states require some physical education (PE) and the energy expended during PE has potential to positively affect energy balance. We previously used 2012 data to examine state policies for PE to calculate estimated student energy expenditure (EEE) under potential (i.e., recommendations followed) and existing conditions. Since then, data have been updated on both state policies and the conduct of PE. Based on updated data, we used PE frequency, duration, and intensity, student mass, and class size to calculate EEE for the delivery of PE under (a) national professional recommendations, (b) 2016 state policies, and (c) school-reported conditions. Although increased from four years ago, only 22 states currently have policies mandating specific PE minutes. EEE over 10years shows the enormous impact PE could have on energy balance. For the average recommended-size PE class, resultant annual EEE based on professional recommendations for min/week far exceeded those based on average state (n=22) policy for min/week by 44.5% for elementary, 62.7% for middle, and 59.5% for high schools. Since 2012 more states adopted policies for PE minutes than dropped them, however, EEE over 10years showed a net loss of 1200kcal/student. With no overall recent improvements in state PE policy and professional recommendations currently not being met, PE remains an underutilized public health resource for EEE. Strong policies, coupled with enhanced accountability of PE teachers and administrators, are needed to ensure PE exists in schools.

  11. Energy use and potential energy conservation for companies and institutions; Energieverbruik en besparingspotentieel bedrijven en instellingen

    Energy Technology Data Exchange (ETDEWEB)

    De Groot, G.M.; Morgenstern, P.P.

    2009-07-01

    The VROM Inspectorate (VI) ordered an investigation to determine which types of companies and institutions would qualify for the VI project Climate and Energy, which aims to stimulate companies to save energy. The project will focus on branches and sectors that, currently, are not participating in government energy conservation agreements or the Greenhouse gas Emission Trading System, but that have a high energy consumption and a significant potential for conserving energy. A large part of the Dutch trade, services and government sector (Handel, Diensten en Overheid (HDO)) qualifies for participation in the project of the VROM Inspectorate. This HDO sector is responsible for 12% of the energy use within the Netherlands and has large energy-saving potential. Many of the branches within this sector use a considerable amount of energy (five petajoules or more), but are not part of any energy conservation agreement. The branches involved are: recreation; healthcare and welfare; wholesale; retail; car trade, maintenance and repairs; food services; and commercial and financial services. The largest energy conservation measures for which the costs could be recovered within five years, relate to power consumption by machines, appliances and lighting. Insulation of existing buildings could also realise substantial energy savings, although the cost-recovery time would be longer and, therefore, these measures often are not mandatory. An important part of the industrial sector, consuming around 30 per cent of the energy within the Netherlands, does not qualify for participation in the VI project. In this sector, around 90% of the energy is used by companies that already participate in energy conservation agreements (the Covenant Benchmarking, and the Long-term agreements on energy efficiency (LTA3)), or in the Greenhouse Gas Emission Trading System (EU ETS). These companies have the largest potential for saving energy. Industrial sectors that, as yet, do not participate in

  12. Dark energy observational evidence and theoretical models

    CERN Document Server

    Novosyadlyj, B; Shtanov, Yu; Zhuk, A

    2013-01-01

    The book elucidates the current state of the dark energy problem and presents the results of the authors, who work in this area. It describes the observational evidence for the existence of dark energy, the methods and results of constraining of its parameters, modeling of dark energy by scalar fields, the space-times with extra spatial dimensions, especially Kaluza---Klein models, the braneworld models with a single extra dimension as well as the problems of positive definition of gravitational energy in General Relativity, energy conditions and consequences of their violation in the presence of dark energy. This monograph is intended for science professionals, educators and graduate students, specializing in general relativity, cosmology, field theory and particle physics.

  13. Canada ocean energy atlas phase 1 : potential tidal current energy resources analysis background

    Energy Technology Data Exchange (ETDEWEB)

    Tarbotton, M.; Larson, M. [Triton Consultants Ltd., Vancouver, BC (Canada)

    2006-05-15

    This report was prepared as a background document for a preliminary tidal current resource inventory for Canadian waters. Energy calculations in the study were based on preliminary estimates of known tidal flows. The inventory was based on nautical charts, Canadian sailing directions, tide and tidal current constituent data, and numerical tidal modelling data. A finite element harmonic tidal model tool was used to provide tidal height and current velocities data for a varying number of tidal constituents. The study identified several major tidal current power resources throughout Canada. It was concluded that modelling studies should concentrate on Minas Basin in Nova Scotia; Georgia and Johnstone Straits in British Columbia; and Hudson's Strait and Ungava Bay. Modelling studies should provide estimates of extractable energy as well as provide initial assessments of the environmental impacts of tidal energy extraction in all 3 regions. 3 refs., 8 tabs., 16 figs.

  14. Modeling global and regional energy futures

    Science.gov (United States)

    Rethinaraj, T. S. Gopi

    A rigorous econometric calibration of a model of energy consumption is presented using a comprehensive time series database on energy consumption and other socioeconomic indicators. The future of nuclear power in the evolving distribution of various energy sources is also examined. An important consideration for the long-term future of nuclear power concerns the rate of decline of the fraction of energy that comes from coal, which has historically declined on a global basis about linearly as a function of the cumulative use of coal. The use of fluid fossil fuels is also expected to eventually decline as the more readily extractable deposits are depleted. The investigation here is restricted to examining a comparatively simple model of the dynamics of competition between nuclear and other competing energy sources. Using a defined tropical/temperate disaggregation of the world, region-specific modeling results are presented for population growth, GDP growth, energy use, and carbon use compatible with a gradual transition to energy sustainability. Results for the fractions of energy use from various sources by grouping nine commercial primary energy sources into pairs of competing fuel categories are presented in combination with the idea of experiential learning and resource depletion. Analysis based on this division provides estimates for future evolution of the fractional shares, annual use rates, cumulative use of individual energy sources, and the economic attractiveness of spent nuclear fuel reprocessing. This unified approach helps to conceptualize and understand the dynamics of evolution of importance of various energy resources over time.

  15. Bandwidth Study on Energy Use and Potential Energy Saving Opportunities in U.S. Pulp and Paper Manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    Sabine Brueske, Caroline Kramer, Aaron Fisher

    2015-06-01

    Energy bandwidth studies of U.S. manufacturing sectors can serve as foundational references in framing the range (or bandwidth) of potential energy savings opportunities. This bandwidth study examines energy consumption and potential energy savings opportunities in U.S. pulp and paper manufacturing. The study relies on multiple sources to estimate the energy used in six individual process areas, representing 52% of sector-wide energy consumption. Energy savings opportunities for individual processes are based on technologies currently in use or under development; the potential savings are then extrapolated to estimate sector-wide energy savings opportunity

  16. Bandwidth Study on Energy Use and Potential Energy Saving Opportunities in U.S. Iron and Steel Manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    Keith Jamison, Caroline Kramer, Sabine Brueske, Aaron Fisher

    2015-06-01

    Energy bandwidth studies of U.S. manufacturing sectors can serve as foundational references in framing the range (or bandwidth) of potential energy savings opportunities. This bandwidth study examines energy consumption and potential energy savings opportunities in U.S. iron and steel manufacturing. The study relies on multiple sources to estimate the energy used in six individual process areas and select subareas, representing 82% of sector-wide energy consumption. Energy savings opportunities for individual processes and subareas are based on technologies currently in use or under development; the potential savings are then extrapolated to estimate sector-wide energy savings opportunity.

  17. Freezing of Energy of a Soliton in an External Potential

    Science.gov (United States)

    Bambusi, D.; Maspero, A.

    2016-05-01

    In this paper we study the dynamics of a soliton in the generalized NLS with a small external potential ɛV of Schwartz class. We prove that there exists an effective mechanical system describing the dynamics of the soliton and that, for any positive integer r, the energy of such a mechanical system is almost conserved up to times of order ɛ - r . In the rotational invariant case we deduce that the true orbit of the soliton remains close to the mechanical one up to times of order ɛ - r .

  18. The Potential Energy Landscape and Mechanisms of Diffusion in Liquids

    OpenAIRE

    Keyes, T.; J. Chowdhary

    2001-01-01

    The mechanism of diffusion in supercooled liquids is investigated from the potential energy landscape point of view, with emphasis on the crossover from high- to low-T dynamics. Molecular dynamics simulations with a time dependent mapping to the associated local mininum or inherent structure (IS) are performed on unit-density Lennard-Jones (LJ). New dynamical quantities introduced include r2_{is}(t), the mean-square displacement (MSD) within a basin of attraction of an IS, R2(t), the MSD of t...

  19. Potential Energy Surfaces Using Algebraic Methods Based on Unitary Groups

    Directory of Open Access Journals (Sweden)

    Renato Lemus

    2011-01-01

    Full Text Available This contribution reviews the recent advances to estimate the potential energy surfaces through algebraic methods based on the unitary groups used to describe the molecular vibrational degrees of freedom. The basic idea is to introduce the unitary group approach in the context of the traditional approach, where the Hamiltonian is expanded in terms of coordinates and momenta. In the presentation of this paper, several representative molecular systems that permit to illustrate both the different algebraic approaches as well as the usual problems encountered in the vibrational description in terms of internal coordinates are presented. Methods based on coherent states are also discussed.

  20. Potential Energy Surfaces and Quantum Yields for Photochromic Diarylethene Reactions

    Directory of Open Access Journals (Sweden)

    Makoto Hatakeyama

    2013-05-01

    Full Text Available Photochromic diarylethenes (DAEs are among the most promising molecular switching systems for future molecular electronics. Numerous derivatives have been synthesized recently, and experimental quantum yields (QYs have been reported for two categories of them. Although the QY is one of the most important properties in various applications, it is also the most difficult property to predict before a molecule is actually synthesized. We have previously reported preliminary theoretical studies on what determines the QYs in both categories of DAE derivatives. Here, reflecting theoretical analyses of potential energy surfaces and recent experimental results, a rational explanation of the general guiding principle for QY design is presented for future molecular design.

  1. Waste characterisation, determining the energy potential of waste

    CSIR Research Space (South Africa)

    Oelofse, Suzanna HH

    2015-11-01

    Full Text Available stream_source_info Oelofse2_2015.pdf.txt stream_content_type text/plain stream_size 4108 Content-Encoding UTF-8 stream_name Oelofse2_2015.pdf.txt Content-Type text/plain; charset=UTF-8 1 Waste characterisation..., determining the energy potential of waste 25 November 2015 by Prof Suzan Oelofse Research Group Leader: Waste for Development Competency Area: Solutions for a Green Economy 2 WtE should consider Fitness for purpose • Feedstock...

  2. Taboo search by successive confinement: Surveying a potential energy surface

    Science.gov (United States)

    Chekmarev, Sergei F.

    2001-09-01

    A taboo search for minima on a potential energy surface (PES) is performed by means of confinement molecular dynamics: the molecular dynamics trajectory of the system is successively confined to various basins on the PES that have not been sampled yet. The approach is illustrated for a 13-atom Lennard-Jones cluster. It is shown that the taboo search radically accelerates the process of surveying the PES, with the probability of finding a new minimum defined by a propagating Fermi-like distribution.

  3. Waste to Energy Potential - A High Concentration Anaerobic Bioreactor

    Science.gov (United States)

    2012-05-23

    REPORT DATE 23 MAY 2012 2. REPORT TYPE 3. DATES COVERED 00-00-2012 to 00-00-2012 4. TITLE AND SUBTITLE Waste to Energy Potential - A High...and fermentative bacteria break down organic carbon to VFAs Acetogens break down VFAs to CH3CO2 − and H2 + Acetoclastic methanogens break...s -999999 999999 7 481 su -999999 999999 0 .. -999999 999999 HCA8 pti Flo$&-tdgc Tan.\\ feed su -999999 999999 0 .. -999999 999999 A-l>o -999999

  4. The Fractional Virial Potential Energy in Two-Component Systems

    Directory of Open Access Journals (Sweden)

    Caimmi, R.

    2008-12-01

    Full Text Available Two-component systems are conceived as macrogases, and the related equation of state is expressed using the virial theorem for subsystems, under the restriction of homeoidally striated density profiles. Explicit calculations are performed for a useful reference case and a few cases of astrophysical interest, both with and without truncation radius. Shallower density profiles are found to yield an equation of state, $phi=phi(y,m$, characterized (for assigned values of the fractional mass, $m=M_j/ M_i$ by the occurrence of two extremum points, a minimum and a maximum, as found in an earlier attempt. Steeper density profiles produce a similar equation of state, which implies that a special value of $m$ is related to a critical curve where the above mentioned extremum points reduce to a single horizontal inflexion point, and curves below the critical one show no extremum points. The similarity of the isofractional mass curves to van der Waals' isothermal curves, suggests the possibility of a phase transition in a bell-shaped region of the $({sf O}yphi$ plane, where the fractional truncation radius along a selected direction is $y=R_j/R_i$, and the fractional virial potential energy is $phi=(E_{ji}_mathrm{vir}/(E_{ij}_mathrm{vir}$. Further investigation is devoted to mass distributions described by Hernquist (1990 density profiles, for which an additional relation can be used to represent a sample of $N=16$ elliptical galaxies (EGs on the $({sf O}yphi$ plane. Even if the evolution of elliptical galaxies and their hosting dark matter (DM haloes, in the light of the model, has been characterized by equal fractional mass, $m$, and equal scaled truncation radius, or concentration, $Xi_u=R_u/r_u^dagger$, $u=i,j$, still it cannot be considered as strictly homologous, due to different values of fractional truncation radii, $y$, or fractional scaling radii, $y^dagger=r_j^dagger/r_i^dagger$, deduced from sample objects.

  5. Office technology energy use and savings potential in New York. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Piette, M.A., Cramer, M., Eto, J., Koomey, J.

    1995-06-01

    This report discusses energy use by office equipment in New York State and the energy savings potential of energy-efficient equipment. A model containing equipment densities and energy-use characteristics for major categories of office equipment has been developed. The model specifies power requirements and hours of use for three modes of average operation for each device: active, standby, and suspend. The energy-use intensity for each device is expressed as a function of the average device density (number of units/1,000 sq ft), the hours of operation in each mode, and the average power requirements in each mode. Output includes an estimate of total energy use (GWh) for each device by building type. Three scenarios are developed. First is a business-as-usual efficiency baseline. Second is a future with increased use of power-managed devices projected under the current Energy Star Computers program sponsored by the US EPA. Third is a scenario that examines energy savings from greater use of products that go well beyond the standard Energy Star products. A series of sensitivity analyses were conducted to explore uncertainties in model inputs. The business-as-usual baseline forecast confirms that office equipment energy use has been rising over the past decade, and may continue to increase for the next decade and beyond. Office equipment currently consumes about 2,900 GWh/year in the State of New York. Under the business-as-usual baseline forecast, this load may increase to 3,300 GWh/year by the year 2000, and approximately double again before 2010. Widespread use of power management technologies adopted with the promotion of the Energy Star program could reduce this load growth by about 30% by the year 2000. Use of more advanced energy-efficient technology could reduce total energy use by office equipment to about 1,900 GWh/year in 2010, which is less than current consumption.

  6. Potential renewable energy resources of the Lerma Valley, Salta, Argentina for its strategic territorial planning

    Energy Technology Data Exchange (ETDEWEB)

    Belmonte, S.; Viramonte, J.G. [Instituto GEONORTE, Facultad de Ciencias Naturales, Universidad Nacional de Salta and CONICET, Avda. Bolivia 5150, Salta CP 4400 (Argentina); Nunez, V. [Instituto de Recursos Naturales y Ecodesarrollo (IRNED), Facultad de Ciencias Naturales, Universidad Nacional de Salta, Avda. Bolivia 5150, Campo Castanares, Salta CP 4400 (Argentina); Franco, J. [Instituto Nacional de Energias No Convencionales (INENCO), Facultad de Ciencias Exactas, Universidad Nacional de Salta, CONICET, Avda. Bolivia 5150, Salta CP 4400 (Argentina)

    2009-08-15

    Renewable energy sources are considered as strategic opportunities to improve the population's quality of life, to promote the development of more efficient and equitable economic systems, and to favor environmental sustainability in the territorial planning of Lerma Valley (Salta, Argentina). The mapping in raster format (each pixel having a reference value) of the potential renewable energy sources (solar, wind, biomass, hydraulic, mixed) is essential to define ideal locations for different types of renewable applications, and to plan suitable strategies for its implementation. It is necessary considering environmental diversity and site conditions (topographic, natural resource, infrastructure and service availability, social and economical) of the intervention area. Different methodologies are used for mapping of potential energy resources. Solar radiation is spatialized through the application of statistical regressions between altitude, latitude, precise incident solar radiation records, and radiation data estimated with the Geosol V.2.0. trademark software. The Argentina Map program is used for the wind potential resource modeling. It requires as inputs: a Digital Elevation Model, a land use and cover map (to determine roughness), and measured and/or estimated wind speed and frequency data. The hydroelectric potential for microturbine applications is calculated from the topographic drop and the annual mean flow in cumulative models, through the application of the Idrisi Kilimanjaro trademark 's runoff tool; while the power densities are compared at the watershed. Biomass potential (at this exploratory stage), is interpreted from the available biomass type (land use and cover map), its energy application availability, and some quantitative indicators associated with the biomass types identified as priority. In conclusion, the renewable energy potential in Lerma Valley is very high and diverse, and its close connection with social

  7. Stochastic Modelling of Energy Systems

    DEFF Research Database (Denmark)

    Andersen, Klaus Kaae

    2001-01-01

    equations are expressed in terms of stochastic differential equations. From a theoretical viewpoint the techniques for experimental design, parameter estimation and model validation are considered. From the practical viewpoint emphasis is put on how this methods can be used to construct models adequate...

  8. Wind and Solar Energy Potential Assessment for Development of Renewables Energies Applications in Bucaramanga, Colombia

    Science.gov (United States)

    Ordóñez, G.; Osma, G.; Vergara, P.; Rey, J.

    2014-06-01

    Currently, the trend of micro-grids and small-scale renewable generation systems implementation in urban environments requires to have historical and detailed information about the energy potential resource in site. In Colombia, this information is limited and do not favor the design of these applications; for this reason, must be made detailed studies of the energy potential in their cities. In this paper is presented the wind and solar energy resource assessment for the city of Bucaramanga, based on the monitoring on four strategic points during the years 2010, 2011 and 2012. According to the analysis, is evidenced a significant solar resource throughout the year ascending on average to 1 734 kWh/m2, equivalent to 4.8 kWh/m2/day. Also, from a wind statistical study based on the Weibull probability distribution and Wind Power Density (WPD) was established the wind potential as Class 1 according to the scale of the Department of Energy of the United States (DOE), since the average speed is near 1.4 m/s. Due this, it is technically unfeasible the using of micro-turbines in the city, even so their potential for natural ventilation of building was analyzed. Finally, is presented a methodology to analyze solar harvesting by sectors in the city, according to the solar motion and shadowing caused by existing structures.

  9. Modeling and Optimization for Piercing Energy Consumption

    Institute of Scientific and Technical Information of China (English)

    XIAO Dong; PAN Xiao-li; YUAN Yong; MAO Zhi-zhong; WANG Fu-li

    2009-01-01

    Energy consumption is an important quality index in the production of seamless tubes. The complex factors affecting energy consumption make it difficult to build its mechanism model, and optimization is also very difficult, if not impossible. The piercing process was divided into three parts based on the production process, and an energy consumption prediction model was proposed based on the step mean value staged multiway partial least square meth-od. On the basis of the batch process prediction model, a genetic algorithm was adopted to calculate the optimum mean value of each process parameter and the minimum piercing energy consumption. Simulation proves that the op-timization method based on the energy consumption prediction model can obtain the optimum process parameters ef-fectively and also provide reliable evidences for practical production.

  10. Modeling approach suitable for energy system

    Energy Technology Data Exchange (ETDEWEB)

    Goetschel, D. V.

    1979-01-01

    Recently increased attention has been placed on optimization problems related to the determination and analysis of operating strategies for energy systems. Presented in this paper is a nonlinear model that can be used in the formulation of certain energy-conversion systems-modeling problems. The model lends itself nicely to solution approaches based on nonlinear-programming algorithms and, in particular, to those methods falling into the class of variable metric algorithms for nonlinearly constrained optimization.

  11. Exact solution of phantom dark energy model

    Institute of Scientific and Technical Information of China (English)

    Wang Wen-Fu; Shui Zheng-Wei; Tang Bin

    2010-01-01

    We investigate the phantom dark energy model derived from the scalar field with a negative kinetic term. By assuming a particular relation between the time derivative of the phantom field and the Hubble function, an exact solution of the model is constructed. Absence of the 'big rip' singularity is shown explicitly. We then derive special features of phantom dark energy model and show that its predictions are consistent with all astrophysical observations.

  12. A Common Optical Potential for $^{4}$He+$^{12}$C at Intermediate Energies

    CERN Document Server

    Hu, Li-Yuan; Hou, Ying-Wei; Liu, Hui-Lan

    2016-01-01

    A common optical potential for $^4$He+$^{12}$C at intermediate bombarding energies, which is essential in analyzing exotic nuclei with $^4$He clusters, was obtained based on the S\\~{a}o Paulo potential (SPP). Among systematic optical potentials for $^4$He+$^{12}$C, this potential has the merit of using a fixed imaginary part of Woods-Saxon form. By optical-model calculations, this potential reproduced the experimental elastic scattering angular distributions of $^4$He+$^{12}$C well within the energy range of 26\\,$A$--60\\,$A$ MeV. It was also applied successfully in calculations of the breakup reactions of $^6$Li+$^{12}$C and $^6$He+$^{12}$C with a three-body continuum discretized coupled-channels method.

  13. A New Method for Characterizing Single Parametric Model Potential

    Institute of Scientific and Technical Information of China (English)

    P.S. Vyas; P.N. Gajjar; B.Y. Thakore; A.R. Jani

    2008-01-01

    A novel approach of characterizing single parametric model potential is proposed by equating total pair wise force to zero.Our well-established single parametric model potential is characterized using the proposed idea and compared the obtained parameter with parameters computed by previously used approaches.Thus characterized pseudopotential is then tested to compute total energy of alkali metals.The results establish the reliability of proposed idea of making total pair wise force to zero in determining the parameter of the pseudopotential.

  14. On Kinetics Modeling of Vibrational Energy Transfer

    Science.gov (United States)

    Gilmore, John O.; Sharma, Surendra P.; Cavolowsky, John A. (Technical Monitor)

    1996-01-01

    Two models of vibrational energy exchange are compared at equilibrium to the elementary vibrational exchange reaction for a binary mixture. The first model, non-linear in the species vibrational energies, was derived by Schwartz, Slawsky, and Herzfeld (SSH) by considering the detailed kinetics of vibrational energy levels. This model recovers the result demanded at equilibrium by the elementary reaction. The second model is more recent, and is gaining use in certain areas of computational fluid dynamics. This model, linear in the species vibrational energies, is shown not to recover the required equilibrium result. Further, this more recent model is inconsistent with its suggested rate constants in that those rate constants were inferred from measurements by using the SSH model to reduce the data. The non-linear versus linear nature of these two models can lead to significant differences in vibrational energy coupling. Use of the contemporary model may lead to significant misconceptions, especially when integrated in computer codes considering multiple energy coupling mechanisms.

  15. Effects of pion-fold-pion diagrams in the energy-independent nucleon-nucleon potential

    Science.gov (United States)

    de Guzman, G.; Kuo, T. T. S.; Holinde, K.; Machleidt, R.; Faessler, A.; Müther, H.

    1985-10-01

    Based on a T-matrix equivalence theory, an energy-independent or locally energy-dependent nucléon-nucléon potential VNN derived from meson exchanges is studied. The potential, given as a series expansion of folded diagrams, is independent of the asymptotic energy of the scattering nucleons. It is, however, locally energy dependent in the sense that its matrix elements depend on the energies associated with its bra and ket states a and b. Our formulation makes use of right-hand-side on-shell T-matrix equivalence of the field-theoretical and potential descriptions when limited to the space of neutrons and protons only. This preserves not only scattering (e.g. phase shifts, projections of wave functions) but also bound-state properties. The matrix elements of V were calculated for two potential models, one based on one-pion exchange (OPEP) and the other on one-boson exchange (OBEP) using {π, ρ, σ, ω, δ, η }. Three types of phase-shift calculations have been carried out to study the viability of constructing an energy-independent potential using the folded-diagram expansion: (A) NN phase shifts for an energy-dependent OPEP and OBEP. For the OBEP we used parameters adjusted to fit experimental data. (B) The same phase shifts for the energy-independent case for both OPEP and OBEP. (C) Repetition of (B) with effects of the two-pion folded diagrams included. Our results show two important points: (i) folded diagrams are of essential importance, and (ii) the first-order folded diagrams contain the dominant effect and the neglect of terms with more than two folds can be regarded as a good approximation. The effects of folded diagrams are large especially for low partial waves and high energies. For high partial waves ( J greater than 2) the folded terms are negligible, and the phase shifts given by (A), (B) and (C) practically coincide.

  16. Potential energy landscape and inherent dynamics of a hard-sphere fluid.

    Science.gov (United States)

    Ma, Qingqing; Stratt, Richard M

    2014-10-01

    Hard-sphere models exhibit many of the same kinds of supercooled-liquid behavior as more realistic models of liquids, but the highly nonanalytic character of their potentials makes it a challenge to think of that behavior in potential energy landscape terms. We show here that it is possible to calculate an important topological property of hard-sphere landscapes, the geodesic pathways through those landscapes, and to do so without artificially coarse-graining or softening the potential. We show, moreover, that the rapid growth of the lengths of those pathways with increasing packing fraction quantitatively predicts the precipitous decline in diffusion constants in a glass-forming hard-sphere mixture model. The geodesic paths themselves can be considered as defining the intrinsic dynamics of hard spheres, so it is also revealing to find that they (and therefore the features of the underlying potential energy landscape) correctly predict the occurrence of dynamic heterogeneity and nonzero values of the non-Gaussian parameter. The success of these landscape predictions for the dynamics of such a singular model emphasizes that there is more to potential energy landscapes than is revealed by looking at the minima and saddle points.

  17. Spatial Statistical Procedures to Validate Input Data in Energy Models

    Energy Technology Data Exchange (ETDEWEB)

    Johannesson, G.; Stewart, J.; Barr, C.; Brady Sabeff, L.; George, R.; Heimiller, D.; Milbrandt, A.

    2006-01-01

    Energy modeling and analysis often relies on data collected for other purposes such as census counts, atmospheric and air quality observations, economic trends, and other primarily non-energy related uses. Systematic collection of empirical data solely for regional, national, and global energy modeling has not been established as in the abovementioned fields. Empirical and modeled data relevant to energy modeling is reported and available at various spatial and temporal scales that might or might not be those needed and used by the energy modeling community. The incorrect representation of spatial and temporal components of these data sets can result in energy models producing misleading conclusions, especially in cases of newly evolving technologies with spatial and temporal operating characteristics different from the dominant fossil and nuclear technologies that powered the energy economy over the last two hundred years. Increased private and government research and development and public interest in alternative technologies that have a benign effect on the climate and the environment have spurred interest in wind, solar, hydrogen, and other alternative energy sources and energy carriers. Many of these technologies require much finer spatial and temporal detail to determine optimal engineering designs, resource availability, and market potential. This paper presents exploratory and modeling techniques in spatial statistics that can improve the usefulness of empirical and modeled data sets that do not initially meet the spatial and/or temporal requirements of energy models. In particular, we focus on (1) aggregation and disaggregation of spatial data, (2) predicting missing data, and (3) merging spatial data sets. In addition, we introduce relevant statistical software models commonly used in the field for various sizes and types of data sets.

  18. Spatial Statistical Procedures to Validate Input Data in Energy Models

    Energy Technology Data Exchange (ETDEWEB)

    Lawrence Livermore National Laboratory

    2006-01-27

    Energy modeling and analysis often relies on data collected for other purposes such as census counts, atmospheric and air quality observations, economic trends, and other primarily non-energy-related uses. Systematic collection of empirical data solely for regional, national, and global energy modeling has not been established as in the above-mentioned fields. Empirical and modeled data relevant to energy modeling is reported and available at various spatial and temporal scales that might or might not be those needed and used by the energy modeling community. The incorrect representation of spatial and temporal components of these data sets can result in energy models producing misleading conclusions, especially in cases of newly evolving technologies with spatial and temporal operating characteristics different from the dominant fossil and nuclear technologies that powered the energy economy over the last two hundred years. Increased private and government research and development and public interest in alternative technologies that have a benign effect on the climate and the environment have spurred interest in wind, solar, hydrogen, and other alternative energy sources and energy carriers. Many of these technologies require much finer spatial and temporal detail to determine optimal engineering designs, resource availability, and market potential. This paper presents exploratory and modeling techniques in spatial statistics that can improve the usefulness of empirical and modeled data sets that do not initially meet the spatial and/or temporal requirements of energy models. In particular, we focus on (1) aggregation and disaggregation of spatial data, (2) predicting missing data, and (3) merging spatial data sets. In addition, we introduce relevant statistical software models commonly used in the field for various sizes and types of data sets.

  19. Decentralized energy: technology assessment and systems description. [Potential for implementation for years 2000 and 2025

    Energy Technology Data Exchange (ETDEWEB)

    Reckard, M K

    1979-06-01

    Decentralized energy systems and their characteristic features are examined in the report. These systems have been divided into six groups for the purpose of analysis: solar, wind, hydro, biomass, geothermal, and coproduction (total energy). The technical and economic potential for the implementation of these systems is discussed for the years 2000 and 2025. The results of a comparison of base-case and decentralized scenarios for the year 2000, using a computer systems model, are presented. Social and institutional factors are also addressed, both as motivations for and results of energy system decentralization. Appendices are included with more detailed technical information on each of the systems groups.

  20. Transportation Energy Futures Series. Potential for Energy Efficiency Improvement Beyond the Light-Duty-Vehicle Sector

    Energy Technology Data Exchange (ETDEWEB)

    Vyas, A. D. [Argonne National Lab. (ANL), Argonne, IL (United States); Patel, D. M. [Argonne National Lab. (ANL), Argonne, IL (United States); Bertram, K. M. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2013-02-01

    Considerable research has focused on energy efficiency and fuel substitution options for light-duty vehicles, while much less attention has been given to medium- and heavy-duty trucks, buses, aircraft, marine vessels, trains, pipeline, and off-road equipment. This report brings together the salient findings from an extensive review of literature on future energy efficiency options for these non-light-duty modes. Projected activity increases to 2050 are combined with forecasts of overall fuel efficiency improvement potential to estimate the future total petroleum and greenhouse gas (GHG) emissions relative to current levels. This is one of a series of reports produced as a result of the Transportation Energy Futures (TEF) project, a Department of Energy-sponsored multi-agency project initiated to pinpoint underexplored strategies for abating GHGs and reducing petroleum dependence related to transportation.

  1. Transportation Energy Futures Series: Potential for Energy Efficiency Improvement Beyond the Light-Duty-Vehicle Sector

    Energy Technology Data Exchange (ETDEWEB)

    Vyas, A. D.; Patel, D. M.; Bertram, K. M.

    2013-03-01

    Considerable research has focused on energy efficiency and fuel substitution options for light-duty vehicles, while much less attention has been given to medium- and heavy-duty trucks, buses, aircraft, marine vessels, trains, pipeline, and off-road equipment. This report brings together the salient findings from an extensive review of literature on future energy efficiency options for these non-light-duty modes. Projected activity increases to 2050 are combined with forecasts of overall fuel efficiency improvement potential to estimate the future total petroleum and greenhouse gas (GHG) emissions relative to current levels. This is one of a series of reports produced as a result of the Transportation Energy Futures (TEF) project, a Department of Energy-sponsored multi-agency project initiated to pinpoint underexplored strategies for abating GHGs and reducing petroleum dependence related to transportation.

  2. Near Shore Wave Modeling and applications to wave energy estimation

    Science.gov (United States)

    Zodiatis, G.; Galanis, G.; Hayes, D.; Nikolaidis, A.; Kalogeri, C.; Adam, A.; Kallos, G.; Georgiou, G.

    2012-04-01

    The estimation of the wave energy potential at the European coastline is receiving increased attention the last years as a result of the adaptation of novel policies in the energy market, the concernsfor global warming and the nuclear energy security problems. Within this framework, numerical wave modeling systems keep a primary role in the accurate description of wave climate and microclimate that is a prerequisite for any wave energy assessment study. In the present work two of the most popular wave models are used for the estimation of the wave parameters at the coastline of Cyprus: The latest parallel version of the wave model WAM (ECMWF version), which employs new parameterization of shallow water effects, and the SWAN model, classically used for near shore wave simulations. The results obtained from the wave models near shores are studied by an energy estimation point of view: The wave parameters that mainly affect the energy temporal and spatial distribution, that is the significant wave height and the mean wave period, are statistically analyzed,focusing onpossible different aspects captured by the two models. Moreover, the wave spectrum distribution prevailing in different areas are discussed contributing, in this way, to the wave energy assessmentin the area. This work is a part of two European projects focusing on the estimation of the wave energy distribution around Europe: The MARINA platform (http://www.marina-platform.info/ index.aspx) and the Ewave (http://www.oceanography.ucy.ac.cy/ewave/) projects.

  3. Renewable energy technologies in the Maldives - determining the potential

    Energy Technology Data Exchange (ETDEWEB)

    van Alphen, Klaas; Hekkert, Marko P. [Department of Innovation Studies, Copernicus Institute for Sustainable Development and Innovation, University of Utrecht, P.O. Box 80115, NL 3508 TC, Utrecht (Netherlands); van Sark, Wilfried G.J.H.M. [Department of Science, Technology and Society, Copernicus Institute for Sustainable Development and Innovation, Utrecht University, Heidelberglaan 2, 3584 CS, Utrecht (Netherlands)

    2007-10-15

    The Maldives is one of the most vulnerable countries to the projected impacts of climate change, due to a combination of the small sizes of the islands and their low height above sea level. Like other small island developing states, the Maldives depends overwhelmingly on petroleum imports for their electricity production, which creates serious economic and financial difficulties. The Government of Maldives is therefore committed to promote sustainable energy and has been actively pursuing several inter-related initiatives to overcome the existing barriers to the utilization of renewable energy technologies. To assist this, the quantification and evaluation of the potentials of available solar and wind resources in the country for electricity applications has been performed. The hybrid system design tool HOMER has been used to create optimal renewable energy (RE) system designs. In order to evaluate these different RE alternatives a multi-criteria analysis is performed using a number of criteria that are likely to be decisive in implementation decisions. The evaluation shows that fully RE system configurations are not financially viable in the Maldives while the RE-diesel hybrid systems could bring down the price of electricity with 5-10 cent/kWh in smaller outer islands. Assuming that these latter systems with a high probability of adoption are implemented, the results show that 10% of the electricity in the Maldives could be supplied by RE based systems in a cost effective way. (author)

  4. Expansion Potentials for Exact Far-from-Equilibrium Spreading of Particles and Energy.

    Science.gov (United States)

    Vasseur, Romain; Karrasch, Christoph; Moore, Joel E

    2015-12-31

    The rates at which energy and particle densities move to equalize arbitrarily large temperature and chemical potential differences in an isolated quantum system have an emergent thermodynamical description whenever the energy or particle current commutes with the Hamiltonian. Concrete examples include the energy current in the 1D spinless fermion model with nearest-neighbor interactions (XXZ spin chain), the energy current in Lorentz-invariant theories or the particle current in interacting Bose gases in arbitrary dimension. Even far from equilibrium, these rates are controlled by state functions, which we call "expansion potentials," expressed as integrals of equilibrium Drude weights. This relation between nonequilibrium quantities and linear response implies nonequilibrium Maxwell relations for the Drude weights. We verify our results via density-matrix renormalization group calculations for the XXZ chain.

  5. Modelling total energy costs of sports centres

    Energy Technology Data Exchange (ETDEWEB)

    Boussabaine, A.H.; Kirkham, R.J.; Grew, R.J. [Liverpool Univ., School of Architecture and Building Engineering, Liverpool (United Kingdom)

    1999-12-07

    Providing and maintaining safe and comfortable conditions in sport centres raises many issues, particularly cost. The paper gives an overview of the factors associated with sport centre servicing and attempts to highlight the governing factors associated with this, particularly energy costs. A total of 19 sport centres in the City of Liverpool in the UK are investigated, using data elicited from the Liverpool Leisure Services Directorate. The energy operating costs were analysed using statistical methods. Six models were developed to predict total energy costs. Testing and validation results showed a high level of model accuracy. The models would be of use to professionals involved in feasibility studies at the design stage. (Author)

  6. Networks of triboelectric nanogenerators for harvesting water wave energy: a potential approach toward blue energy.

    Science.gov (United States)

    Chen, Jun; Yang, Jin; Li, Zhaoling; Fan, Xing; Zi, Yunlong; Jing, Qingshen; Guo, Hengyu; Wen, Zhen; Pradel, Ken C; Niu, Simiao; Wang, Zhong Lin

    2015-03-24

    With 70% of the earth's surface covered with water, wave energy is abundant and has the potential to be one of the most environmentally benign forms of electric energy. However, owing to lack of effective technology, water wave energy harvesting is almost unexplored as an energy source. Here, we report a network design made of triboelectric nanogenerators (TENGs) for large-scale harvesting of kinetic water energy. Relying on surface charging effect between the conventional polymers and very thin layer of metal as electrodes for each TENG, the TENG networks (TENG-NW) that naturally float on the water surface convert the slow, random, and high-force oscillatory wave energy into electricity. On the basis of the measured output of a single TENG, the TENG-NW is expected to give an average power output of 1.15 MW from 1 km(2) surface area. Given the compelling features, such as being lightweight, extremely cost-effective, environmentally friendly, easily implemented, and capable of floating on the water surface, the TENG-NW renders an innovative and effective approach toward large-scale blue energy harvesting from the ocean.

  7. Potential strategic consequences of the nuclear energy revival

    Energy Technology Data Exchange (ETDEWEB)

    Ferguson, Ch.D.

    2010-07-01

    Many people have projected their hopes and fears onto nuclear power. Nuclear energy has both benefits and risks, and disagreement persists about whether this energy source is, on balance, more of an asset than a liability. This debate involves a complicated set of factors that are difficult to assess, let alone fully resolve because of the differing interests in various countries' use and pursuit of nuclear power. Renewed interest throughout the globe in harnessing this energy source has stoked this perennial debate and raised concern about security threats from states and non-state actors while holding out the promise of more electricity for more people. While the motivations for nuclear energy vary among states, the two primary public goods this energy source offers are countering human-induced climate change and providing for greater energy security. Although views on how to achieve energy security differ, the essential aspect for nuclear energy is that for several countries, especially those with scarce indigenous energy sources from fossil fuels, investing in nuclear power plants diversifies electricity production portfolios and helps reduce dependence on foreign sources of energy. The focus here is on assessing the potential security consequences of increased use of nuclear power in the existing nuclear power states and most importantly in many more states that have in recent years expressed interest in this power source. The risks of nuclear power include possible reactor accidents, release of radioactive waste to the environment, attacks on or sabotage of nuclear facilities, and misuse of peaceful nuclear technologies to make nuclear weapons. While safety of nuclear plants and disposal of radioactive waste are important issues, this paper analyzes the latter two issues. In addition, it addresses two under-examined risks: military attacks on nuclear facilities and the effects on security alliances and conventional arms buildups as more countries seek to

  8. The JRC-EU-TIMES model. Bioenergy potentials for EU and neighbouring countries

    NARCIS (Netherlands)

    Ruiz, Pablo; Sgobbi, Alessandra; Nijs, Wouter; Thiel, Christian; Longa, Dalla Francesco; Kober, Tom; Elbersen, Berien; Hengeveld, G.M.

    2015-01-01

    The JRC-EU-TIMES is a partial equilibrium energy system model maintained by the Institute for Energy and Transport (IET) of the Joint Research Centre (JRC) to analyse the role of energy technologies development and their potential contribution to decarbonisation pathways of the energy system. The te

  9. Bohr Hamiltonian with an energy dependent $\\gamma$-unstable Coulomb-like potential

    CERN Document Server

    Budaca, R

    2016-01-01

    An exact analytical solution for the Bohr Hamiltonian with an energy dependent Coulomb-like $\\gamma$-unstable potential is presented. Due to the linear energy dependence of the potential's coupling constant, the corresponding spectrum in the asymptotic limit of the slope parameter resembles the spectral structure of the spherical vibrator, however with a different state degeneracy. The parameter free energy spectrum as well as the transition rates for this case are given in closed form and duly compared with those of the harmonic $U(5)$ dynamical symmetry. The model wave functions are found to exhibit properties that can be associated to shape coexistence. A possible experimental realization of the model is found in few medium nuclei with a very low second $0^{+}$ state known to exhibit competing prolate, oblate and spherical shapes.

  10. Bohr Hamiltonian with an energy-dependent γ-unstable Coulomb-like potential

    Energy Technology Data Exchange (ETDEWEB)

    Budaca, R. [Horia Hulubei National Institute of Physics and Nuclear Engineering, Bucharest-Magurele (Romania)

    2016-10-15

    An exact analytical solution for the Bohr Hamiltonian with an energy-dependent Coulomb-like γ-unstable potential is presented. Due to the linear energy dependence of the potential's coupling constant, the corresponding spectrum in the asymptotic limit of the slope parameter resembles the spectral structure of the spherical vibrator, however with a different state degeneracy. The parameter free energy spectrum as well as the transition rates for this case are given in closed form and duly compared with those of the harmonic U(5) dynamical symmetry. The model wave functions are found to exhibit properties that can be associated to shape coexistence. A possible experimental realization of the model is found in few medium nuclei with a very low second 0{sup +} state known to exhibit competing prolate, oblate and spherical shapes. (orig.)

  11. ROMANIA'S ENERGY POTENTIAL OF RENEWABLE ENERGIES IN THE CONTEXT OF SUSTAINABLE DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    Maghear Diana

    2011-12-01

    environmental pollution as well as the depletion of the conventional resources that are highly polluting, highlighting the energy potential that renewable energy resources Romania has. This issue will be extensively discussed in the thesis entitled 'The necessity and importance of sustainable development of Romania. Case study on the use of renewable energies for heating the population in the western part of Romania' which I intend to realize and support at The West University of Timisoara, Faculty of Economics and Business Administration, under the guidance of Professor Doctor Laura Cismas.

  12. Motor systems energy efficiency supply curves: A methodology for assessing the energy efficiency potential of industrial motor systems

    Energy Technology Data Exchange (ETDEWEB)

    McKane, Aimee [Industrial Energy Analysis, Energy Analysis Department, Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd. MS 90R4000, Berkeley, CA 94720 (United States); Hasanbeigi, Ali, E-mail: AHasanbeigi@lbl.gov [China Energy Group, Energy Analysis Department, Environmental Energy Technologies Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Rd. MS 90R4000, Berkeley, CA 94720 (United States)

    2011-10-15

    Motor-driven equipment accounts for approximately 60% of manufacturing final electricity use worldwide. A major barrier to effective policymaking, and to more global acceptance of the energy efficiency potential in industrial motor systems, is the lack of a transparent methodology for quantifying the magnitude and cost-effectiveness of these energy savings. This paper presents the results of groundbreaking analyses conducted for five countries and one region to begin to address this barrier. Using a combination of expert opinion and available data from the United States, Canada, the European Union, Thailand, Vietnam, and Brazil, bottom-up energy efficiency supply curve models were constructed to estimate the cost-effective electricity efficiency potentials and CO{sub 2} emission reduction for three types of motor systems (compressed air, pumping, and fan) in industry for the selected countries/region. Based on these analyses, the share of cost-effective electricity saving potential of these systems as compared to the total motor system energy use in the base year varies between 27% and 49% for pumping, 21% and 47% for compressed air, and 14% and 46% for fan systems. The total technical saving potential varies between 43% and 57% for pumping, 29% and 56% for compressed air, and 27% and 46% for fan systems. - Highlights: > Development of conservation supply curves for the industrial motor systems. > An innovative approach combining available aggregate country-level data with expert opinion. > Results show both cost-effective and technical potential for energy saving and their costs. > Policy implication of the results are briefly discussed.

  13. Computed Potential Energy Surfaces and Minimum Energy Pathways for Chemical Reactions

    Science.gov (United States)

    Walch, Stephen P.; Langhoff, S. R. (Technical Monitor)

    1994-01-01

    Computed potential energy surfaces are often required for computation of such parameters as rate constants as a function of temperature, product branching ratios, and other detailed properties. For some dynamics methods, global potential energy surfaces are required. In this case, it is necessary to obtain the energy at a complete sampling of all the possible arrangements of the nuclei, which are energetically accessible, and then a fitting function must be obtained to interpolate between the computed points. In other cases, characterization of the stationary points and the reaction pathway connecting them is sufficient. These properties may be readily obtained using analytical derivative methods. We have found that computation of the stationary points/reaction pathways using CASSCF/derivative methods, followed by use of the internally contracted CI method to obtain accurate energetics, gives usefull results for a number of chemically important systems. The talk will focus on a number of applications including global potential energy surfaces, H + O2, H + N2, O(3p) + H2, and reaction pathways for complex reactions, including reactions leading to NO and soot formation in hydrocarbon combustion.

  14. Modelling in nuclear energy environments

    Directory of Open Access Journals (Sweden)

    M. Samaras

    2008-12-01

    Full Text Available Producing energy to supply the demands of our societies is reaching a critical limit. To tackle this issue, there is a slow renaissance of fission reactors and the push to realise fusion reactors. The safe, reliable and optimal performance of fusion and fission plants is dependent on the choice of suitable materials used as components and fuels. As these materials are degraded by their exposure to high temperatures, irradiation and a corrosive environment, it is necessary to address the issue of long term degradation of materials under service exposure in advanced plants. A higher confidence in life-time assessments of these materials requires an understanding of the related physical phenomena on a range of scales from the atomic level of single defect energetics all the way up to macroscopic effects.

  15. Modeling Rotating Turbulent Flows with the Body Force Potential Model.

    Science.gov (United States)

    Bhattacharya, Amitabh; Perot, Blair

    2000-11-01

    Like a Reynolds Stress Transport equation model, the turbulent potential model has an explicit Coriolis acceleration term that appears in the model that accounts for rotation effects. In this work the additional secondary effects that system rotation has on the dissipation rate, return-to-isotropy, and fast pressure strain terms are also included in the model. The resulting model is tested in the context of rotating isotropic turbulence, rotating homogeneous shear flow, rotating channel flow, and swirling pipe flow. Many of the model changes are applicable to Reynolds stress transport equation models. All model modifications are frame indifferent.

  16. Building an Efficient Model for Afterburn Energy Release

    Energy Technology Data Exchange (ETDEWEB)

    Alves, S; Kuhl, A; Najjar, F; Tringe, J; McMichael, L; Glascoe, L

    2012-02-03

    Many explosives will release additional energy after detonation as the detonation products mix with the ambient environment. This additional energy release, referred to as afterburn, is due to combustion of undetonated fuel with ambient oxygen. While the detonation energy release occurs on a time scale of microseconds, the afterburn energy release occurs on a time scale of milliseconds with a potentially varying energy release rate depending upon the local temperature and pressure. This afterburn energy release is not accounted for in typical equations of state, such as the Jones-Wilkins-Lee (JWL) model, used for modeling the detonation of explosives. Here we construct a straightforward and efficient approach, based on experiments and theory, to account for this additional energy release in a way that is tractable for large finite element fluid-structure problems. Barometric calorimeter experiments have been executed in both nitrogen and air environments to investigate the characteristics of afterburn for C-4 and other materials. These tests, which provide pressure time histories, along with theoretical and analytical solutions provide an engineering basis for modeling afterburn with numerical hydrocodes. It is toward this end that we have constructed a modified JWL equation of state to account for afterburn effects on the response of structures to blast. The modified equation of state includes a two phase afterburn energy release to represent variations in the energy release rate and an afterburn energy cutoff to account for partial reaction of the undetonated fuel.

  17. Energy-dissipation-model for metallurgical multi-phase-systems

    Energy Technology Data Exchange (ETDEWEB)

    Mavrommatis, K.T. [Rheinisch-Westfaelische Technische Hochschule Aachen, Aachen (Germany)

    1996-12-31

    Entropy production in real processes is directly associated with the dissipation of energy. Both are potential measures for the proceed of irreversible processes taking place in metallurgical systems. Many of these processes in multi-phase-systems could then be modelled on the basis of the energy-dissipation associated with. As this entity can often be estimated using very simple assumptions from first principles, the evolution of an overall measure of systems behaviour can be studied constructing an energy-dissipation -based model of the system. In this work a formulation of this concept, the Energy-Dissipation-Model (EDM), for metallurgical multi-phase-systems is given. Special examples are studied to illustrate the concept, and benefits as well as the range of validity are shown. This concept might be understood as complement to usual CFD-modelling of complex systems on a more abstract level but reproducing essential attributes of complex metallurgical systems. (author)

  18. A two measure model of dark energy and dark matter

    Energy Technology Data Exchange (ETDEWEB)

    Guendelman, Eduardo [Department of Physics, Ben-Gurion University, Beer-Sheva (Israel); Singleton, Douglas; Yongram, N., E-mail: guendel@bgu.ac.il, E-mail: dougs@csufresno.edu, E-mail: nattapongy@nu.ac.th [Physics Department, California State University Fresno, Fresno, CA 93740 (United States)

    2012-11-01

    In this work we construct a unified model of dark energy and dark matter. This is done with the following three elements: a gravitating scalar field, φ with a non-conventional kinetic term, as in the string theory tachyon; an arbitrary potential, V(φ); two measures — a metric measure ((−g){sup 1/2}) and a non-metric measure (Φ). The model has two interesting features: (i) For potentials which are unstable and would give rise to tachyonic scalar field, this model can stabilize the scalar field. (ii) The form of the dark energy and dark matter that results from this model is fairly insensitive to the exact form of the scalar field potential.

  19. 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...

  20. A global energy model with fusion

    Energy Technology Data Exchange (ETDEWEB)

    Lechon, Yolanda [CIEMAT, Avda Complutense 22, 28040 Madrid (Spain)]. E-mail: yolanda.lechon@ciemat.es; Cabal, H. [CIEMAT, Avda Complutense 22, 28040 Madrid (Spain); Varela, M. [CIEMAT, Avda Complutense 22, 28040 Madrid (Spain); Saez, R. [CIEMAT, Avda Complutense 22, 28040 Madrid (Spain); Eherer, C. [TUG/ITP, Petersgasse 16, 8010 Graz (Austria); Baumann, M. [TUG/ITP, Petersgasse 16, 8010 Graz (Austria); Dueweke, J. [IPP, Boltzmannstr. 2, D-85748 Garching (Germany); Hamacher, T. [IPP, Boltzmannstr. 2, D-85748 Garching (Germany); Tosato, G.C. [EFDA Close Support Unit, Boltzmannstr. 2, D-85748 Garching (Germany)

    2005-11-15

    Some analysts expect a complete shift of the global energy system in the 21st century, away from fossil fuels to either renewable sources or new nuclear technologies [L. Schrattenholzer, A roadmap to a sustainable global energy system, in: Proceedings of the International Energy Workshop, Paris, June, 2004]. Fusion might become a corner stone of the future energy system. The construction and successful operation of ITER is a necessary condition to reach this goal. Within the Socio Economic Research on Fusion (SERF) programme guided by EFDA, a consortium between CIEMAT, TU Graz (TUG), ENEA and IPP open to other European energy and fusion research laboratories has been formed to analyse the possible role of fusion in the future energy system. Using TIMES, a single region global model has been constructed including fusion as an energy option. Background of the model is a detailed bottom-up description of the complete energy system starting from mining process up to the various demand sectors. The model dynamics is determined by an optimisation process, in which total surplus is maximized. The paper will present the first attempts to set-up a single region global model and the first results.

  1. World Energy Projection System model documentation

    Energy Technology Data Exchange (ETDEWEB)

    Hutzler, M.J.; Anderson, A.T.

    1997-09-01

    The World Energy Projection System (WEPS) was developed by the Office of Integrated Analysis and Forecasting within the Energy Information Administration (EIA), the independent statistical and analytical agency of the US Department of Energy. WEPS is an integrated set of personal computer based spreadsheets containing data compilations, assumption specifications, descriptive analysis procedures, and projection models. The WEPS accounting framework incorporates projections from independently documented models and assumptions about the future energy intensity of economic activity (ratios of total energy consumption divided by gross domestic product GDP), and about the rate of incremental energy requirements met by natural gas, coal, and renewable energy sources (hydroelectricity, geothermal, solar, wind, biomass, and other renewable resources). Projections produced by WEPS are published in the annual report, International Energy Outlook. This report documents the structure and procedures incorporated in the 1998 version of the WEPS model. It has been written to provide an overview of the structure of the system and technical details about the operation of each component of the model for persons who wish to know how WEPS projections are produced by EIA.

  2. Energy of Cohesion, Compressibility, and the Potential Energy Functions of the Graphite System

    Science.gov (United States)

    Girifalco, L. A.; Lad, R. A.

    1956-01-01

    The lattice summations of the potential energy of importance in the graphite system have been computed by direct summation assuming a Lennard-Jones 6-12 potential between carbon atoms. From these summations, potential energy curves were constructed for interactions between a carbon atom and a graphite monolayer, between a carbon atom and a graphite surface, between a graphite monolayer and a semi-infinite graphite crystal and between two graphite semi-infinite crystals. Using these curves, the equilibrium distance between two isolated physically interacting carbon atoms was found to be 2.70 a, where a is the carbon-carbon distance in a graphite sheet. The distance between a surface plane and the rest of the crystal was found to be 1.7% greater than the interlayer spacing. Theoretical values of the energy of cohesion and the compressibility were calculated from the potential curve for the interaction between two semi-infinite crystals. They were (delta)E(sub c) = -330 ergs/sq cm and beta =3.18x10(exp -12)sq cm/dyne, respectively. These compared favorably with the experimental values of (delta)E(sub c) = -260 ergs/sq cm and beta = 2.97 X 10(exp -2) sq cm/dyne.

  3. An integrated assessment of the potential of agricultural and forestry residues for energy production in China

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Ji [Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081 China; Zhang, Aiping [Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081 China; Lam, Shu Kee [Crop and Soil Sciences Section, Faculty of Veterinary and Agricultural Sciences, the University of Melbourne, Melbourne Vic. 3010 Australia; Zhang, Xuesong [Joint Global Change Research Institute, Pacific Northwest National Laboratory and University of Maryland, College Park MD 20740 USA; Great Lakes Bioenergy Research Center, Michigan State University, East Lansing MI 48824 USA; Thomson, Allison M. [Field to Market, The Alliance for Sustainable Agriculture, 777 N Capitol St. NE Suite 803 Washington DC 20002 USA; Lin, Erda [Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing 100081 China; Jiang, Kejun [Energy Research Institute (ERI), Beijing 100038 China; Clarke, Leon E. [Joint Global Change Research Institute, Pacific Northwest National Laboratory and University of Maryland, College Park MD 20740 USA; Edmonds, James A. [Joint Global Change Research Institute, Pacific Northwest National Laboratory and University of Maryland, College Park MD 20740 USA; Kyle, Page G. [Joint Global Change Research Institute, Pacific Northwest National Laboratory and University of Maryland, College Park MD 20740 USA; Yu, Sha [Joint Global Change Research Institute, Pacific Northwest National Laboratory and University of Maryland, College Park MD 20740 USA; Zhou, Yuyu [Department of Geological & Atmospheric Sciences, Iowa State University, Ames IA 50011 USA; Zhou, Sheng [Institutes of Energy, Environment and Economy, Tsinghua University, Beijing 100084 China

    2016-01-05

    Biomass has been widely recognized as an important energy source with high potential to reduce greenhouse gas emissions while minimizing environmental pollution. In this study, we employ the Global Change Assessment Model to estimate the potential of agricultural and forestry residue biomass for energy production in China. Potential availability of residue biomass as an energy source was analyzed for the 21st century under different climate policy scenarios. Currently, the amount of total annual residue biomass, averaged over 2003-2007, is around 15519PJ in China, consisting of 10818PJ from agriculture residues (70%) and 4701PJ forestry residues (30%). We estimate that 12693PJ of the total biomass is available for energy production, with 66% derived from agricultural residue and 34% from forestry residue. Most of the available residue is from south central China (3347PJ), east China (2862PJ) and south-west China (2229PJ), which combined exceeds 66% of the total national biomass. Under the reference scenario without carbon tax, the potential availability of residue biomass for energy production is projected to be 3380PJ by 2050 and 4108PJ by 2095, respectively. When carbon tax is imposed, biomass availability increases substantially. For the CCS 450ppm scenario, availability of biomass increases to 9002PJ (2050) and 11524PJ (2095), respectively. For the 450ppm scenario without CCS, 9183 (2050) and 11150PJ (2095) residue biomass, respectively, is projected to be available. Moreover, the implementation of CCS will have a little impact on the supply of residue biomass after 2035. Our results suggest that residue biomass has the potential to be an important component in China's sustainable energy production portfolio. As a low carbon emission energy source, climate change policies that involve carbon tariff and CCS technology promote the use of residue biomass for energy production in a low carbon-constrained world.

  4. Directory of Energy Information Administration Models 1993

    Energy Technology Data Exchange (ETDEWEB)

    1993-07-06

    This directory contains descriptions about each model, including the title, acronym, purpose, followed by more detailed information on characteristics, uses, and requirements. Sources for additional information are identified. Included in this directory are 35 EIA models active as of May 1, 1993. Models that run on personal computers are identified by ``PC`` as part of the acronym. EIA is developing new models, a National Energy Modeling System (NEMS), and is making changes to existing models to include new technologies, environmental issues, conservation, and renewables, as well as extend forecast horizon. Other parts of the Department are involved in this modeling effort. A fully operational model is planned which will integrate completed segments of NEMS for its first official application--preparation of EIA`s Annual Energy Outlook 1994. Abstracts for the new models will be included in next year`s version of this directory.

  5. Directory of energy information administration models 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-13

    This updated directory has been published annually; after this issue, it will be published only biennially. The Disruption Impact Simulator Model in use by EIA is included. Model descriptions have been updated according to revised documentation approved during the past year. This directory contains descriptions about each model, including title, acronym, purpose, followed by more detailed information on characteristics, uses, and requirements. Sources for additional information are identified. Included are 37 EIA models active as of February 1, 1995. The first group is the National Energy Modeling System (NEMS) models. The second group is all other EIA models that are not part of NEMS. Appendix A identifies major EIA modeling systems and the models within these systems. Appendix B is a summary of the `Annual Energy Outlook` Forecasting System.

  6. Analytic Models of Plausible Gravitational Lens Potentials

    Energy Technology Data Exchange (ETDEWEB)

    Baltz, Edward A.; Marshall, Phil; Oguri, Masamune

    2007-05-04

    Gravitational lenses on galaxy scales are plausibly modeled as having ellipsoidal symmetry and a universal dark matter density profile, with a Sersic profile to describe the distribution of baryonic matter. Predicting all lensing effects requires knowledge of the total lens potential: in this work we give analytic forms for that of the above hybrid model. Emphasizing that complex lens potentials can be constructed from simpler components in linear combination, we provide a recipe for attaining elliptical symmetry in either projected mass or lens potential.We also provide analytic formulae for the lens potentials of Sersic profiles for integer and half-integer index. We then present formulae describing the gravitational lensing effects due to smoothly-truncated universal density profiles in cold dark matter model. For our isolated haloes the density profile falls off as radius to the minus fifth or seventh power beyond the tidal radius, functional forms that allow all orders of lens potential derivatives to be calculated analytically, while ensuring a non-divergent total mass. We show how the observables predicted by this profile differ from that of the original infinite-mass NFW profile. Expressions for the gravitational flexion are highlighted. We show how decreasing the tidal radius allows stripped haloes to be modeled, providing a framework for a fuller investigation of dark matter substructure in galaxies and clusters. Finally we remark on the need for finite mass halo profiles when doing cosmological ray-tracing simulations, and the need for readily-calculable higher order derivatives of the lens potential when studying catastrophes in strong lenses.

  7. Transfer of Energy, Potential, and Current by Alfv\\'en Waves in Solar Flares

    CERN Document Server

    Melrose, D B

    2013-01-01

    Alfv\\'en waves play three related roles in the impulsive phase of a solar flare: they transport energy from a generator region to an acceleration region; they map the cross-field potential (associated with the driven energy release) from the generator region onto the acceleration region; and within the acceleration region they damp by setting up a parallel electric field that accelerates electrons and transfers the wave energy to them. The Alfv\\'en waves may also be regarded as setting up new closed current loops, with field-aligned currents that close across field lines at boundaries. A model is developed for large-amplitude Alfv\\'en waves that shows how Alfv\\'en waves play these roles in solar flares. A picket-fence structure for the current flow is incorporated into the model to account for the "number problem" and the energy of the accelerated electrons.

  8. Modelling the energy transition in cities

    Energy Technology Data Exchange (ETDEWEB)

    Huber, Felix [Wuppertal Univ. (Germany). Dept. of Civil Engineering; Schwarze, Bjoern; Spiekermann, Klaus; Wegener, Michael [Spiekermann und Wegener Urban and Regional Research, Dortmund (Germany)

    2013-09-01

    The history of cities is a history of energy transitions. In the medieval city heating and cooking occurred with wood and peat. The growth of the industrial city in the 19th century was built on coal and electricity. The sprawling metropolis of the 20th century was made possible by oil and gas. How will the city of the 21st century look after the next energy transition from fossil to renewable energy? This paper reports on the extension of an urban land-use transport interaction model to a model of the energy transition in the Ruhr Area, a five-million agglomeration in Germany. The paper presents the planned model extensions and how they are to be integrated into the model and shows first preliminary results.

  9. Energy expressions for Kohn-Sham potentials and their relation to the Slater-Janak theorem.

    Science.gov (United States)

    Elkind, Pavel D; Staroverov, Viktor N

    2012-03-28

    Direct approximation of exchange-correlation potentials is a promising approach to accurate prediction of molecular response properties. However, little is known about ways of obtaining total energies from model potentials other than by using the Levy-Perdew virial relation. We introduce and explore several alternative formulas which arise as line integrals of potentials taken along density scaling and aufbau-filling paths, and which are not limited to the exchange term. The relaxed-orbital variant of the aufbau-path energy expression is shown to be closely related to the Slater-Janak theorem. Although the Levy-Perdew relation generally yields reasonable energies for all model exchange potentials, the relaxed-orbital aufbau path gives better results for those potentials that predict accurate highest-occupied orbital eigenvalues, such as the potential of Räsänen, Pittalis, and Proetto [J. Chem. Phys. 132, 044112 (2010)]. The ideas presented in this work may guide the development of new types of density-functional approximations for exchange and correlation.

  10. Scalar-fluid interacting dark energy: Cosmological dynamics beyond the exponential potential

    Science.gov (United States)

    Dutta, Jibitesh; Khyllep, Wompherdeiki; Tamanini, Nicola

    2017-01-01

    We extend the dynamical systems analysis of scalar-fluid interacting dark energy models performed in C. G. Boehmer et al., Phys. Rev. D 91, 123002 (2015), 10.1103/PhysRevD.91.123002 by considering scalar field potentials beyond the exponential type. The properties and stability of critical points are examined using a combination of linear analysis, computational methods and advanced mathematical techniques, such as center manifold theory. We show that the interesting results obtained with an exponential potential can generally be recovered also for more complicated scalar field potentials. In particular, employing power law and hyperbolic potentials as examples, we find late time accelerated attractors, transitions from dark matter to dark energy domination with specific distinguishing features, and accelerated scaling solutions capable of solving the cosmic coincidence problem.

  11. Generalized Skyrme model with the loosely bound potential

    CERN Document Server

    Gudnason, Sven Bjarke; Ma, Nana

    2016-01-01

    We study a generalization of the loosely bound Skyrme model which consists of the Skyrme model with a sixth-order derivative term and the second-order loosely bound potential. We use the rational map approximation for the 4-Skyrmion and calculate the binding energy and estimate the systematic error in using the latter approximation. In the parameter space that we can explore within the rational map approximation, we find classical binding energies as low as 1.8% and once taking into account the contribution from spin-isospin quantization we obtain binding energies as low as 5.3%. We also calculate the contribution from the sixth-order derivative term to the electric charge density and axial coupling.

  12. Biogas from poultry waste-production and energy potential.

    Science.gov (United States)

    Dornelas, Karoline Carvalho; Schneider, Roselene Maria; do Amaral, Adriana Garcia

    2017-08-01

    The objective of this study was to evaluate the effect of heat treatment on poultry litter with different levels of reutilisation for potential generation of biogas in experimental biodigesters. Chicken litter used was obtained from two small-scale poultry houses where 14 birds m(-2) were housed for a period of 42 days per cycle. Litter from aviary 1 received no heat treatment while each batch of litter produced from aviary 2 underwent a fermentation process. For each batch taken, two biodigesters were set for each aviary, with hydraulic retention time of 35 days. The efficiency of the biodigestion process was evaluated by biogas production in relation to total solids (TS) added, as well as the potential for power generation. Quantified volumes ranged from 8.9 to 41.1 L of biogas for aviary 1, and 6.7 to 33.9 L of biogas for aviary 2, with the sixth bed reused from both aviaries registering the largest biogas potential. Average potential biogas in m(3) kg(-1) of TS added were 0.022 to 0.034 for aviary 1 and 0.015 to 0.022 for aviary 2. Energy values ​​of biogas produced were calculated based on calorific value and ranged from 0.06 to 0.33 kWh for chicken litter without fermentation and from 0.05 to 0.27 kWh for chicken litter with fermentation. It was concluded that the re-use of poultry litter resulted in an increase in biogas production, and the use of fermentation in the microbiological treatment of poultry litter seems to have negatively influenced production of biogas.

  13. Energy-based models for environmental biotechnology.

    Science.gov (United States)

    Rodríguez, Jorge; Lema, Juan M; Kleerebezem, Robbert

    2008-07-01

    Environmental biotechnology is evolving. Current process objectives include the production of chemicals and/or energy carriers (biofuels) in addition to the traditional objective of removing pollutants from waste. To maximise product yields and minimise biomass production, future processes will rely on anaerobic microbial communities. Anaerobic processes are characterised by small Gibbs energy changes in the reactions catalysed, and this provides clear thermodynamic process boundaries. Here, a Gibbs-energy-based methodology is proposed for mathematical modelling of energy-limited anaerobic ecosystems. This methodology provides a basis for the description of microbial activities as a function of environmental factors, which will allow enhanced catalysis of specific reactions of interest for process development.

  14. Improved DFT Potential Energy Surfaces via Improved Densities.

    Science.gov (United States)

    Kim, Min-Cheol; Park, Hansol; Son, Suyeon; Sim, Eunji; Burke, Kieron

    2015-10-01

    Density-corrected DFT is a method that cures several failures of self-consistent semilocal DFT calculations by using a more accurate density instead. A novel procedure employs the Hartree-Fock density to bonds that are more severely stretched than ever before. This substantially increases the range of accurate potential energy surfaces obtainable from semilocal DFT for many heteronuclear molecules. We show that this works for both neutral and charged molecules. We explain why and explore more difficult cases, for example, CH(+), where density-corrected DFT results are even better than sophisticated methods like CCSD. We give a simple criterion for when DC-DFT should be more accurate than self-consistent DFT that can be applied for most cases.

  15. Potential alternative energy technologies on the Outer Continental Shelf.

    Energy Technology Data Exchange (ETDEWEB)

    Elcock, D.; Environmental Assessment

    2007-04-20

    This technical memorandum (TM) describes the technology requirements for three alternative energy technologies for which pilot and/or commercial projects on the U.S. Outer Continental Shelf (OCS) are likely to be proposed within the next five to seven years. For each of the alternative technologies--wind, wave, and ocean current--the TM first presents an overview. After each technology-specific overview, it describes the technology requirements for four development phases: site monitoring and testing, construction, operation, and decommissioning. For each phase, the report covers the following topics (where data are available): facility description, electricity generated, ocean area (surface and bottom) occupied, resource requirements, emissions and noise sources, hazardous materials stored or used, transportation requirements, and accident potential. Where appropriate, the TM distinguishes between pilot-scale (or demonstration-scale) facilities and commercial-scale facilities.

  16. Investigation of international energy economics. [Use of econometric model EXPLOR

    Energy Technology Data Exchange (ETDEWEB)

    Deonigi, D.E.; Clement, M.; Foley, T.J.; Rao, S.A.

    1977-03-01

    The Division of International Affairs of the Energy Research and Development Administration is assessing the long-range economic effects of energy research and development programs in the U.S. and other countries, particularly members of the International Energy Agency (IEA). In support of this effort, a program was designed to coordinate the capabilities of five research groups--Rand, Virginia Polytechnic Institute, Brookhaven National Laboratory, Lawrence Livermore Laboratory, and Pacific Northwest Laboratory. The program could evaluate the international economics of proposed or anticipated sources of energy. This program is designed to be general, flexible, and capable of evaluating a diverse collection of potential energy (nuclear and nonnuclear) related problems. For example, the newly developed methodology could evaluate the international and domestic economic impact of nuclear-related energy sources, but also existing nonnuclear and potential energy sources such as solar, geothermal, wind, etc. Major items to be included would be the cost of exploration, cost of production, prices, profit, market penetration, investment requirements and investment goods, economic growth, change in balance of payments, etc. In addition, the changes in cost of producing all goods and services would be identified for each new energy source. PNL developed (1) a means of estimating the demands for major forms of energy by country, and (2) a means of identifying results or impacts on each country. The results for each country were then to be compared to assess relative advantages. PNL relied on its existing general econometric model, EXPLOR, to forecast the demand for energy by country. (MCW)

  17. Models for the energy performance of low-energy houses

    DEFF Research Database (Denmark)

    Andersen, Philip Hvidthøft Delff

    such as mechanical ventilation, floor heating, and control of the lighting effect, the heat dynamics must be taken into account. Hence, this thesis provides methods for data-driven modeling of heat dynamics of modern buildings. While most of the work in this thesis is related to characterization of heat dynamics...... - referred to as "grey-box” modeling - one-step predictions can be generated and used for model validation by testing statistically whether the model describes all variation and dynamics observed in the data. The possibility of validating the model dynamics is a great advantage from the use of stochastic......-building. The building is well-insulated and features large modern energy-effcient windows and oor heating. These features lead to increased non-linear responses to solar radiation and longer time constants. The building is equipped with advanced control and measuring equipment. Experiments are designed and performed...

  18. Modeling Innovations Advance Wind Energy Industry

    Science.gov (United States)

    2009-01-01

    In 1981, Glenn Research Center scientist Dr. Larry Viterna developed a model that predicted certain elements of wind turbine performance with far greater accuracy than previous methods. The model was met with derision from others in the wind energy industry, but years later, Viterna discovered it had become the most widely used method of its kind, enabling significant wind energy technologies-like the fixed pitch turbines produced by manufacturers like Aerostar Inc. of Westport, Massachusetts-that are providing sustainable, climate friendly energy sources today.

  19. Renewable energy technologies in the Maldives - Realizing the potential

    Energy Technology Data Exchange (ETDEWEB)

    Alphen, Klaas van; Hekkert, Marko P. [Department of Innovation Studies, Copernicus Institute for Sustainable Development and Innovation, University of Utrecht, P.O. Box 80115, NL 3508 TC, Utrecht (Netherlands); Sark, Wilfried G.J.H.M. van [Department of Science, Technology and Society, Copernicus Institute for Sustainable Development and Innovation, Utrecht University, Heidelberglaan 2, 3584 CS, Utrecht (Netherlands)

    2008-01-15

    Like in many Small Island Developing States, the techno-economic potential of renewable energy technologies (RETs) in the Maldives is substantial. However, it is not certain that these economically viable RETs will indeed be implemented and utilized, since this is greatly influenced by various social, institutional and political factors (i.e., the Innovation System). In order to steer away from activities that enhance the current fossil fuel based lock-in situation and create an environment that increases the chance of a successful transfer and diffusion of RETs, several projects have been set up in the Maldives. These projects have been initiated by the Global Environmental Facility, the United Nations Development Program, and the European Commission. In this article we evaluate these projects by analyzing whether or not they strengthen the local Renewable Energy Innovation System. This evaluation shows that these RE programs strengthen most of the key processes necessary in an Innovation System conducive to technology transfer. However, as not enough attention is being paid to local entrepreneurial activities and the creation of a domestic market for RETs, the process of RET transfer might run the risk of stagnation after completion of the RE programs. (author)

  20. Onshore wind energy in Baden-Württemberg: a bottom-up economic assessment of the socio-technical potential

    OpenAIRE

    2015-01-01

    Detailed information about the potentials and costs of renewable energies is an important input factor for energy system models, as well as commercial and political decision-making processes. With its increasing locally installed capacity and hub height, wind energy plays an important role when it comes to meeting climate targets and optimizing electricity networks. Recently however, wind energy has faced more and more social barriers and land use constraints which can negatively impact both ...

  1. The energy trilogy: An integrated sustainability model to bridge wastewater treatment plant energy and emissions gaps

    Science.gov (United States)

    Al-Talibi, A. Adhim

    An estimated 4% of national energy consumption is used for drinking water and wastewater services. Despite the awareness and optimization initiatives for energy conservation, energy consumption is on the rise owing to population and urbanization expansion and to commercial and industrial business advancement. The principal concern is since energy consumption grows, the higher will be the energy production demand, leading to an increase in CO2 footprints and the contribution to global warming potential. This research is in the area of energy-water nexus, focusing on wastewater treatment plant (WWTP) energy trilogy -- the group of three related entities, which includes processes: (1) consuming energy, (2) producing energy, and (3) the resulting -- CO2 equivalents. Detailed and measurable energy information is not readily obtained for wastewater facilities, specifically during facility preliminary design phases. These limitations call for data-intensive research approach on GHG emissions quantification, plant efficiencies and source reduction techniques. To achieve these goals, this research introduced a model integrating all plant processes and their pertinent energy sources. In a comprehensive and "Energy Source-to-Effluent Discharge" pattern, this model is capable of bridging the gaps of WWTP energy, facilitating plant designers' decision-making for meeting energy assessment, sustainability and the environmental regulatory compliance. Protocols for estimating common emissions sources are available such as for fuels, whereas, site-specific emissions for other sources have to be developed and are captured in this research. The dissertation objectives were met through an extensive study of the relevant literature, models and tools, originating comprehensive lists of processes and energy sources for WWTPs, locating estimation formulas for each source, identifying site specific emissions factors, and linking the sources in a mathematical model for site specific CO2 e

  2. Alpine Windharvest: development of information base regarding potentials and the necessary technical, legal and socio-economic conditions for expanding wind energy in the Alpine Space - Alpine Space wind map - Modeling approach

    Energy Technology Data Exchange (ETDEWEB)

    Schaffner, B.; Remund, J. [Meteotest, Berne (Switzerland)

    2005-07-01

    This report presents describes the development work carried out by the Swiss meteorology specialists of the company METEOTEST as part of a project carried out together with the Swiss wind-energy organisation 'Suisse Eole'. The framework for the project is the EU Interreg IIIB Alpine Space Programme, a European Community Initiative Programme funded by the European Regional Development Fund. The project investigated the use of digital relief-analysis. The series of reports describes the development and use of a basic information system to aid the investigation of the technical, legal and socio-economical conditions for the use of wind energy in the alpine area. This report discusses two modelling approaches investigated for use in the definition of a wind map for the alpine area. The method chosen and its application are discussed. The various sources of information for input to the model are listed and discussed.

  3. The sea surface currents as a potential factor in the estimation and monitoring of wave energy potential

    Science.gov (United States)

    Zodiatis, George; Galanis, George; Nikolaidis, Andreas; Stylianoy, Stavros; Liakatas, Aristotelis

    2015-04-01

    The use of wave energy as an alternative renewable is receiving attention the last years under the shadow of the economic crisis in Europe and in the light of the promising corresponding potential especially for countries with extended coastline. Monitoring and studying the corresponding resources is further supported by a number of critical advantages of wave energy compared to other renewable forms, like the reduced variability and the easier adaptation to the general grid, especially when is jointly approached with wind power. Within the framework, a number of countries worldwide have launched research and development projects and a significant number of corresponding studies have been presented the last decades. However, in most of them the impact of wave-sea surface currents interaction on the wave energy potential has not been taken into account neglecting in this way a factor of potential importance. The present work aims at filling this gap for a sea area with increased scientific and economic interest, the Eastern Mediterranean Sea. Based on a combination of high resolution numerical modeling approach with advanced statistical tools, a detailed analysis is proposed for the quantification of the impact of sea surface currents, which produced from downscaling the MyOcean-FO regional data, to wave energy potential. The results although spatially sensitive, as expected, prove beyond any doubt that the wave- sea surface currents interaction should be taken into account for similar resource analysis and site selection approaches since the percentage of impact to the available wave power may reach or even exceed 20% at selected areas.

  4. On energy conversion in a sigma coordinate ocean model

    Energy Technology Data Exchange (ETDEWEB)

    Eldevik, Tor

    1999-08-01

    Energy diagnostics are useful for understanding the transfer of energy through instabilities and between different scales. In this note the conservation equations for kinetic and potential energy, divided into suitable mean and eddy quantities, for a sigma coordinate ocean model are set up. By identifying the transfer terms responsible for the conservative conversions between the different energies, an energy flow diagram is suggested. The motivation for this is twofold. Firstly, the average operator required for dividing the quantities of the flow into mean and eddy parts is in general not well defined in Cartesian coordinates when the upper and lower boundaries are not at fixed vertical levels. This is overcome by introducing the ''terrain-following'' sigma as the vertical coordinate. Secondly, and most important, many of today's numerical ocean models have this as the vertical coordinate. (author)

  5. The potential of energy farming in the southeastern California desert

    Science.gov (United States)

    Lew, V.

    1980-04-01

    The use of energy forms to provide future sources of energy for California is considered. Marginal desert lands in southeastern California are proposed for the siting of energy farms using acacia, eucalyptus, euphorbia, guayule, jojoba, mesquite, or tamarisk.

  6. Policy modeling for industrial energy use

    Energy Technology Data Exchange (ETDEWEB)

    Worrell, Ernst; Park, Hi-Chun; Lee, Sang-Gon; Jung, Yonghun; Kato, Hiroyuki; Ramesohl, Stephan; Boyd, Gale; Eichhammer, Wolfgang; Nyboer, John; Jaccard, Mark; Nordqvist, Joakim; Boyd, Christopher; Klee, Howard; Anglani, Norma; Biermans, Gijs

    2003-03-01

    The international workshop on Policy Modeling for Industrial Energy Use was jointly organized by EETA (Professional Network for Engineering Economic Technology Analysis) and INEDIS (International Network for Energy Demand Analysis in the Industrial Sector). The workshop has helped to layout the needs and challenges to include policy more explicitly in energy-efficiency modeling. The current state-of-the-art models have a proven track record in forecasting future trends under conditions similar to those faced in the recent past. However, the future of energy policy in a climate-restrained world is likely to demand different and additional services to be provided by energy modelers. In this workshop some of the international models used to make energy consumption forecasts have been discussed as well as innovations to enable the modeling of policy scenarios. This was followed by the discussion of future challenges, new insights in the data needed to determine the inputs into energy model s, and methods to incorporate decision making and policy in the models. Based on the discussion the workshop participants came to the following conclusions and recommendations: Current energy models are already complex, and it is already difficult to collect the model inputs. Hence, new approaches should be transparent and not lead to extremely complex models that try to ''do everything''. The model structure will be determined by the questions that need to be answered. A good understanding of the decision making framework of policy makers and clear communication on the needs are essential to make any future energy modeling effort successful. There is a need to better understand the effects of policy on future energy use, emissions and the economy. To allow the inclusion of policy instruments in models, evaluation of programs and instruments is essential, and need to be included in the policy instrument design. Increased efforts are needed to better understand the

  7. The modelling of future energy scenarios for Denmark

    DEFF Research Database (Denmark)

    Kwon, Pil Seok

    2014-01-01

    for the important but uncertain areas biomass and flexible demand are performed. Thirdly, modelling-related issues are investigated with a focus on the effect of future forecasting assumption and differences between a predefined priority order and order determined by given efficiencies and constraints...... the overall energy system model for analyzing three subjects which are important but uncertain areas in the future. The first model is a consequential LCA analysis for biomass potential. The second model targets transport demand due to uncertain technology development in the future transport sector. The third...... performance, more than a quarter of the classic electricity demand would need to be flexible within a month, which is highly unlikely to happen. For the investigation of the energy system model, EnergyPLAN, which is used for two scenario analyses, two questions are asked; “what is the value of future...

  8. Holographic dark energy in the DGP model

    Energy Technology Data Exchange (ETDEWEB)

    Cruz, Norman [Universidad de Santiago, Departamento de Fisica, Facultad de Ciencia, Santiago (Chile); Lepe, Samuel [Pontificia Universidad Catolica de Valparaiso, Instituto de Fisica, Facultad de Ciencias, Valparaiso (Chile); Pena, Francisco [Universidad de La Frontera, Departamento de Ciencias Fisicas, Facultad de Ingenieria, Ciencias y Administracion, Avda. Francisco Salazar 01145, Casilla 54-D, Temuco (Chile); Avelino, Arturo [Universidad de Guanajuato, Departamento de Fisica, DCI, Codigo Postal 37150, Leon, Guanajuato (Mexico)

    2012-09-15

    The braneworld model proposed by Dvali, Gabadadze, and Porrati leads to an accelerated universe without cosmological constant or any other form of dark energy. Nevertheless, we have investigated the consequences of this model when an holographic dark energy is included, taking the Hubble scale as IR cutoff. We have found that the holographic dark energy leads to an accelerated flat universe (de Sitter-like expansion) for the two branches: {epsilon}={+-}1, of the DGP model. Nevertheless, in universes with no null curvature the dark energy presents an EoS corresponding to a phantom fluid during the present era and evolving to a de Sitter-like phase for future cosmic time. In the special case in which the holographic parameter c is equal to one we have found a sudden singularity in closed universes. In this case the expansion is decelerating. (orig.)

  9. Potential Coastal Pumped Hydroelectric Energy Storage Locations Identified using GIS-based Topographic Analysis

    Science.gov (United States)

    Parsons, R.; Barnhart, C. J.; Benson, S. M.

    2013-12-01

    Large-scale electrical energy storage could accommodate variable, weather dependent energy resources such as wind and solar. Pumped hydroelectric energy storage (PHS) and compressed energy storage area (CAES) have life cycle energy and financial costs that are an order of magnitude lower than conventional electrochemical storage technologies. However PHS and CAES storage technologies require specific geologic conditions. Conventional PHS requires an upper and lower reservoir separated by at least 100 m of head, but no more than 10 km in horizontal distance. Conventional PHS also impacts fresh water supplies, riparian ecosystems, and hydrologic environments. A PHS facility that uses the ocean as the lower reservoir benefits from a smaller footprint, minimal freshwater impact, and the potential to be located near off shore wind resources and population centers. Although technologically nascent, today one coastal PHS facility exists. The storage potential for coastal PHS is unknown. Can coastal PHS play a significant role in augmenting future power grids with a high faction of renewable energy supply? In this study we employ GIS-based topographic analysis to quantify the coastal PHS potential of several geographic locations, including California, Chile and Peru. We developed automated techniques that seek local topographic minima in 90 m spatial resolution shuttle radar topography mission (SRTM) digital elevation models (DEM) that satisfy the following criteria conducive to PHS: within 10 km from the sea; minimum elevation 150 m; maximum elevation 1000 m. Preliminary results suggest the global potential for coastal PHS could be very significant. For example, in northern Chile we have identified over 60 locations that satisfy the above criteria. Two of these locations could store over 10 million cubic meters of water or several GWh of energy. We plan to report a global database of candidate coastal PHS locations and to estimate their energy storage capacity.

  10. A computer simulation of a potential derived from the gay-berne potential for lattice model

    Directory of Open Access Journals (Sweden)

    Habtamu Zewdie

    2000-06-01

    Full Text Available The lattice model of elongated molecules interacting via a potential derived from the Gay-Berne pair potential is proposed. We made a systematic study of the effect of varying the molecular elongation and intermolecular vector orientation dependence of the pair potential on the thermodynamic as well as the structural properties of liquid crystals. A Monte Carlo simulations of molecules placed at the site of a simple cubic lattice and interacting via the modified Gay-Berne potential with its nearest neighbours is performed. The internal energy, heat capacity, angular pair correlation function and scalar order parameter are obtained. The results are compared against predictions of molecular field theory, experimental results and that of other related simulations wherever possible. It is shown that for more elongated molecules the nematic-isotropic transition becomes stronger first order transition. For a given molecular elongation as the intermolecular vector orientation dependence becomes larger the nematic-isotropic transition becomes a stronger first order transition as measured by the rate of change of the order parameter and the divergence of the heat capacity. Scaling the potential well seems to have dramatic change on the effect of the potential well anisotropy on trends of nematic-isotropic transition temperature and divergence of the heat capacity. It is shown that the behaviour of many nematics can be described by proposed model with the elongation ratio of molecules and potential well anisotropy ranging from 3 to 5.

  11. New holographic dark energy model with non-linear interaction

    CERN Document Server

    Oliveros, A

    2014-01-01

    In this paper the cosmological evolution of a holographic dark energy model with a non-linear interaction between the dark energy and dark matter components in a FRW type flat universe is analysed. In this context, the deceleration parameter $q$ and the equation state $w_{\\Lambda}$ are obtained. We found that, as the square of the speed of sound remains positive, the model is stable under perturbations since early times; it also shows that the evolution of the matter and dark energy densities are of the same order for a long period of time, avoiding the so--called coincidence problem. We have also made the correspondence of the model with the dark energy densities and pressures for the quintessence and tachyon fields. From this correspondence we have reconstructed the potential of scalar fields and their dynamics.

  12. Modeling energy expenditure in children and adolescents using quantile regression

    Science.gov (United States)

    Advanced mathematical models have the potential to capture the complex metabolic and physiological processes that result in energy expenditure (EE). Study objective is to apply quantile regression (QR) to predict EE and determine quantile-dependent variation in covariate effects in nonobese and obes...

  13. Inflation with hyperbolic potential in the braneworld model

    Indian Academy of Sciences (India)

    Dilip Paul; Bikash Chandra Paul; Xin-He Meng

    2009-05-01

    In this paper we study inflationary dynamics with a scalar field in an inverse coshyperbolic potential in the braneworld model. We note that a sufficient inflation may be obtained with the potential considering slow-roll approximation in the high energy limit. We determine the minimum values of the initial inflaton field required to obtain sufficient inflation and also determine the relevant inflationary parameters. The numerical values of spectral index of the scalar perturbation spectrum are determined by varying the number of e-foldings for different initial values of the inflaton field. The result obtained here is in good agreement with the current observational limits.

  14. Modeling auditory evoked potentials to complex stimuli

    DEFF Research Database (Denmark)

    Rønne, Filip Munch

    The auditory evoked potential (AEP) is an electrical signal that can be recorded from electrodes attached to the scalp of a human subject when a sound is presented. The signal is considered to reflect neural activity in response to the acoustic stimulation and is a well established clinical...... clinically and in research towards using realistic and complex stimuli, such as speech, to electrophysiologically assess the human hearing. However, to interpret the AEP generation to complex sounds, the potential patterns in response to simple stimuli needs to be understood. Therefore, the model was used...... to simulate auditory brainstem responses (ABRs) evoked by classic stimuli like clicks, tone bursts and chirps. The ABRs to these simple stimuli were compared to literature data and the model was shown to predict the frequency dependence of tone-burst ABR wave-V latency and the level-dependence of ABR wave...

  15. Homogeneous connectivity of potential energy network in a solidlike state of water cluster.

    Science.gov (United States)

    Akimoto, Takuma; Kaneko, Toshihiro; Yasuoka, Kenji; Zeng, Xiao Cheng

    2013-06-28

    A novel route to the exponential trapping-time distribution within a solidlike state in water clusters is described. We propose a simple homogeneous network (SHN) model to investigate dynamics on the potential energy networks of water clusters. In this model, it is shown that the trapping-time distribution in a solidlike state follows the exponential distribution, whereas the trapping-time distribution in local potential minima within the solidlike state is not exponential. To confirm the exponential trapping-time distribution in a solidlike state, we investigate water clusters, (H2O)6 and (H2O)12, by molecular dynamics simulations. These clusters change dynamically from solidlike to liquidlike state and vice versa. We find that the probability density functions of trapping times in a solidlike state are described by the exponential distribution whereas those of interevent times of large fluctuations in potential energy within the solidlike state follow the Weibull distributions. The results provide a clear evidence that transition dynamics between solidlike and liquidlike states in water clusters are well described by the SHN model, suggesting that the exponential trapping-time distribution within a solidlike state originates from the homogeneous connectivity in the potential energy network.

  16. Revolutions in energy through modeling and simulation

    Energy Technology Data Exchange (ETDEWEB)

    Tatro, M.; Woodard, J.

    1998-08-01

    The development and application of energy technologies for all aspects from generation to storage have improved dramatically with the advent of advanced computational tools, particularly modeling and simulation. Modeling and simulation are not new to energy technology development, and have been used extensively ever since the first commercial computers were available. However, recent advances in computing power and access have broadened the extent and use, and, through increased fidelity (i.e., accuracy) of the models due to greatly enhanced computing power, the increased reliance on modeling and simulation has shifted the balance point between modeling and experimentation. The complex nature of energy technologies has motivated researchers to use these tools to understand better performance, reliability and cost issues related to energy. The tools originated in sciences such as the strength of materials (nuclear reactor containment vessels); physics, heat transfer and fluid flow (oil production); chemistry, physics, and electronics (photovoltaics); and geosciences and fluid flow (oil exploration and reservoir storage). Other tools include mathematics, such as statistics, for assessing project risks. This paper describes a few advancements made possible by these tools and explores the benefits and costs of their use, particularly as they relate to the acceleration of energy technology development. The computational complexity ranges from basic spreadsheets to complex numerical simulations using hardware ranging from personal computers (PCs) to Cray computers. In all cases, the benefits of using modeling and simulation relate to lower risks, accelerated technology development, or lower cost projects.

  17. On the hydrologic adjustment of climate-model projections: The potential pitfall of potential evapotranspiration

    Science.gov (United States)

    Milly, P.C.D.; Dunne, K.A.

    2011-01-01

    Hydrologic models often are applied to adjust projections of hydroclimatic change that come from climate models. Such adjustment includes climate-bias correction, spatial refinement ("downscaling"), and consideration of the roles of hydrologic processes that were neglected in the climate model. Described herein is a quantitative analysis of the effects of hydrologic adjustment on the projections of runoff change associated with projected twenty-first-century climate change. In a case study including three climate models and 10 river basins in the contiguous United States, the authors find that relative (i.e., fractional or percentage) runoff change computed with hydrologic adjustment more often than not was less positive (or, equivalently, more negative) than what was projected by the climate models. The dominant contributor to this decrease in runoff was a ubiquitous change in runoff (median 211%) caused by the hydrologic model's apparent amplification of the climate-model-implied growth in potential evapotranspiration. Analysis suggests that the hydrologic model, on the basis of the empirical, temperature-based modified Jensen-Haise formula, calculates a change in potential evapotranspiration that is typically 3 times the change implied by the climate models, which explicitly track surface energy budgets. In comparison with the amplification of potential evapotranspiration, central tendencies of other contributions from hydrologic adjustment (spatial refinement, climate-bias adjustment, and process refinement) were relatively small. The authors' findings highlight the need for caution when projecting changes in potential evapotranspiration for use in hydrologic models or drought indices to evaluate climatechange impacts on water. Copyright ?? 2011, Paper 15-001; 35,952 words, 3 Figures, 0 Animations, 1 Tables.

  18. A Meta Model for Domestic Energy Consumption

    Directory of Open Access Journals (Sweden)

    K.,J SREEKANTH

    2011-01-01

    Full Text Available Prediction of energy consumption particularly in micro level is of vital importance in terms of energy planning and also implementation of any Clean Development Mechanism (CDM activities that has become the order of the world today. It may be difficult to model household energy consumption using conventional methods such as time series forecasting due to many influencing factors. This paper presents a step wise regression model for forecasting domestic energy consumption based on micro level household survey data collected from Kerala, a state in southern part of India. The analysis of the data reveals significant influence of socio-economic, demographic, geographic, and family attributes upon total household energy requirements. While a wide variation in the pattern of energy requirements across the domestic sector belonging to different expenditure classes, per capita income level can be identified as the most important explanatory variable influencing variation in energy requirements. The models developed also demonstrates the influence of per capita land area, residential area among the higher income group while average age and literacy forms significant variables among the lower income group.

  19. Interacting Dark Energy Models and Observations

    Science.gov (United States)

    Shojaei, Hamed; Urioste, Jazmin

    2017-01-01

    Dark energy is one of the mysteries of the twenty first century. Although there are candidates resembling some features of dark energy, there is no single model describing all the properties of dark energy. Dark energy is believed to be the most dominant component of the cosmic inventory, but a lot of models do not consider any interaction between dark energy and other constituents of the cosmic inventory. Introducing an interaction will change the equation governing the behavior of dark energy and matter and creates new ways to explain cosmic coincidence problem. In this work we studied how the Hubble parameter and density parameters evolve with time in the presence of certain types of interaction. The interaction serves as a way to convert dark energy into matter to avoid a dark energy-dominated universe by creating new equilibrium points for the differential equations. Then we will use numerical analysis to predict the values of distance moduli at different redshifts and compare them to the values for the distance moduli obtained by WMAP (Wilkinson Microwave Anisotropy Probe). Undergraduate Student

  20. Effects of atmospheric variability on energy utilization and conservation. [Space heating energy demand modeling; Program HEATLOAD

    Energy Technology Data Exchange (ETDEWEB)

    Reiter, E.R.; Johnson, G.R.; Somervell, W.L. Jr.; Sparling, E.W.; Dreiseitly, E.; Macdonald, B.C.; McGuirk, J.P.; Starr, A.M.

    1976-11-01

    Research conducted between 1 July 1975 and 31 October 1976 is reported. A ''physical-adaptive'' model of the space-conditioning demand for energy and its response to changes in weather regimes was developed. This model includes parameters pertaining to engineering factors of building construction, to weather-related factors, and to socio-economic factors. Preliminary testing of several components of the model on the city of Greeley, Colorado, yielded most encouraging results. Other components, especially those pertaining to socio-economic factors, are still under development. Expansion of model applications to different types of structures and larger regions is presently underway. A CRT-display model for energy demand within the conterminous United States also has passed preliminary tests. A major effort was expended to obtain disaggregated data on energy use from utility companies throughout the United States. The study of atmospheric variability revealed that the 22- to 26-day vacillation in the potential and kinetic energy modes of the Northern Hemisphere is related to the behavior of the planetary long-waves, and that the midwinter dip in zonal available potential energy is reflected in the development of blocking highs. Attempts to classify weather patterns over the eastern and central United States have proceeded satisfactorily to the point where testing of our method for longer time periods appears desirable.