WorldWideScience

Sample records for net energy production

  1. Net energy yield from production of conventional oil

    International Nuclear Information System (INIS)

    Dale, Michael; Krumdieck, Susan; Bodger, Pat

    2011-01-01

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

  2. Energy intensity ratios as net energy measures of United States energy production and expenditures

    International Nuclear Information System (INIS)

    King, C W

    2010-01-01

    In this letter I compare two measures of energy quality, energy return on energy invested (EROI) and energy intensity ratio (EIR) for the fossil fuel consumption and production of the United States. All other characteristics being equal, a fuel or energy system with a higher EROI or EIR is of better quality because more energy is provided to society. I define and calculate the EIR for oil, natural gas, coal, and electricity as measures of the energy intensity (units of energy divided by money) of the energy resource relative to the energy intensity of the overall economy. EIR measures based upon various unit prices for energy (e.g. $/Btu of a barrel of oil) as well as total expenditures on energy supplies (e.g. total dollars spent on petroleum) indicate net energy at different points in the supply chain of the overall energy system. The results indicate that EIR is an easily calculated and effective proxy for EROI for US oil, gas, coal, and electricity. The EIR correlates well with previous EROI calculations, but adds additional information on energy resource quality within the supply chain. Furthermore, the EIR and EROI of oil and gas as well as coal were all in decline for two time periods within the last 40 years, and both time periods preceded economic recessions.

  3. Energy balance of maize production in Brazil: the energetic constraints of a net positive outcome

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Luis Henrique de Barros; Alves, Bruno Jose Rodrigues; Urquiaga, Segundo

    2008-07-01

    Among the factors used to analyze and to establish the sustainability of a whole agricultural production system, the energy balance is one of the most powerful and robust. The maize production in Brazil is surely the reflex of an energy intensive system that demands many field operations and heavy fertilizer applications, notably nitrogen in urea form. This work presents an energy balance of this major crop adjusted to the Brazilian conditions of cultivation. The input components were grouped based on their energy contents, and the possible improvements in the agricultural practices that could improve energy balance and net energy withdrawn from the farming were considered. The replacement of N synthetic fertilizer by biological nitrogen fixation, whether the process is directly carried out by endophytic diazotroph bacteria or by means of a N{sub 2}- fixing legume culture planted before the main crop as a green-manure is also discussed. (author)

  4. Net Zero Energy Buildings

    DEFF Research Database (Denmark)

    Marszal, Anna Joanna; Bourrelle, Julien S.; Gustavsen, Arild

    2010-01-01

    and identify possible renewable energy supply options which may be considered in calculations. Finally, the gap between the methodology proposed by each organisation and their respective national building code is assessed; providing an overview of the possible changes building codes will need to undergo......The international cooperation project IEA SHC Task 40 / ECBCS Annex 52 “Towards Net Zero Energy Solar Buildings”, attempts to develop a common understanding and to set up the basis for an international definition framework of Net Zero Energy Buildings (Net ZEBs). The understanding of such buildings...

  5. Energy self-reliance, net-energy production and GHG emissions in Danish organic cash crop farms

    DEFF Research Database (Denmark)

    Halberg, Niels; Dalgaard, Randi; Olesen, Jørgen E

    2008-01-01

    -energy production were modeled. Growing rapeseed on 10% of the land could produce bio-diesel to replace 50-60% of the tractor diesel used on the farm. Increasing grass-clover area to 20% of the land and using half of this yield for biogas production could change the cash crop farm to a net energy producer......, and reduce GHG emissions while reducing the overall output of products only marginally. Increasing grass-clover area would improve the nutrient management on the farm and eliminate dependence on conventional pig slurry if the biogas residues were returned to cash crop fields...

  6. Subcritical ethylic biodiesel production from wet animal fat and vegetable oils: A net energy ratio analysis

    International Nuclear Information System (INIS)

    Sales, Emerson A.; Ghirardi, Maria L.; Jorquera, Orlando

    2017-01-01

    Highlights: • Using ethanol in subcritical thermodynamic conditions, without catalysts. • The net energy ratio-NER identifies opportunities for industrial application. • The presence of water and free fatty acids improved the TG conversion. • Transesterification reactions of animal fat, soybean and palm oils. - Abstract: Ethylic transesterification process for biodiesel production without any chemical or biochemical catalysts at different subcritical thermodynamic conditions was performed using wet animal fat, soybean and palm oils as feedstock. The results indicate that 2 h of reaction at 240 °C with pressures varying from 20 to 45 bar was sufficient to transform almost all lipid fraction of the samples to biodiesel, depending on the reactor dead volume and proportions between reactants. Conversions of 100%, 84% and 98.5% were obtained for animal fat, soybean oil and palm oil, respectively, in the presence of water, with a net energy ration values of 2.6, 2.1 and 2.5 respectively. These results indicate that the process is energetically favorable, and thus represents a cleaner technology with environmental advantages when compared to traditional esterification or transesterification processes.

  7. Turkey's net energy consumption

    International Nuclear Information System (INIS)

    Soezen, Adnan; Arcaklioglu, Erol; Oezkaymak, Mehmet

    2005-01-01

    The main goal of this study is to develop the equations for forecasting net energy consumption (NEC) using an artificial neural-network (ANN) technique in order to determine the future level of energy consumption in Turkey. In this study, two different models were used in order to train the neural network. In one of them, population, gross generation, installed capacity and years are used in the input layer of the network (Model 1). Other energy sources are used in input layer of network (Model 2). The net energy consumption is in the output layer for two models. Data from 1975 to 2003 are used for the training. Three years (1981, 1994 and 2003) are used only as test data to confirm this method. The statistical coefficients of multiple determinations (R 2 -value) for training data are equal to 0.99944 and 0.99913 for Models 1 and 2, respectively. Similarly, R 2 values for testing data are equal to 0.997386 and 0.999558 for Models 1 and 2, respectively. According to the results, the net energy consumption using the ANN technique has been predicted with acceptable accuracy. Apart from reducing the whole time required, with the ANN approach, it is possible to find solutions that make energy applications more viable and thus more attractive to potential users. It is also expected that this study will be helpful in developing highly applicable energy policies

  8. Army Net Zero Prove Out. Net Zero Energy Best Practices

    Science.gov (United States)

    2014-11-18

    recovery and cogeneration opportunities, offsetting the remaining demand with the production of renewable energy from onsite sources so that the Net...implementing energy recovery and cogeneration opportunities, and then offsetting the remaining demand with the production of renewable energy from on-site...they impact overall energy performance. The use of energy modeling in the design stage provides insights that can contribute to more effective design

  9. NASA Net Zero Energy Buildings Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    Pless, S.; Scheib, J.; Torcellini, P.; Hendron, B.; Slovensky, M.

    2014-10-01

    In preparation for the time-phased net zero energy requirement for new federal buildings starting in 2020, set forth in Executive Order 13514, NASA requested that the National Renewable Energy Laboratory (NREL) to develop a roadmap for NASA's compliance. NASA detailed a Statement of Work that requested information on strategic, organizational, and tactical aspects of net zero energy buildings. In response, this document presents a high-level approach to net zero energy planning, design, construction, and operations, based on NREL's first-hand experience procuring net zero energy construction, and based on NREL and other industry research on net zero energy feasibility. The strategic approach to net zero energy starts with an interpretation of the executive order language relating to net zero energy. Specifically, this roadmap defines a net zero energy acquisition process as one that sets an aggressive energy use intensity goal for the building in project planning, meets the reduced demand goal through energy efficiency strategies and technologies, then adds renewable energy in a prioritized manner, using building-associated, emission- free sources first, to offset the annual energy use required at the building; the net zero energy process extends through the life of the building, requiring a balance of energy use and production in each calendar year.

  10. WE-NET. Substask 4. Development of hydrogen production technologies; 1998 nendo suiso riyo kokusai clean energy system gijutsu (WE-NET). 4. Suiso seizo gijutsu no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    Under the hydrogen-utilizing international clean energy system technology project WE-NET (World Energy NET Work), researches were conducted aiming at the establishment of a hydrogen production technology through electrolysis of polymer electrolyte solution. In fiscal 1998, element technologies were developed for the development of high-efficiency/large-capacity water electrolyzing plants using electrodeless deposition and hot pressing, research and investigation of optimum operating conditions were conducted, and a service plant conceptual design and a polymer electrolytic membrane were developed. In addition, literature was searched for the current state of ion exchange membranes and water electrolysis, both indispensable for the hydrogen production technology discussed in this paper. In the field of lamination of large cells (electrode surface:2500cm{sup 2}), an excellent energy efficiency level exceeding 90% set as the target for a large laminated cell performance test was achieved - 92.6% by electrodeless deposition and 94.4% by hot pressing. As for polymer membranes capable of resisting high temperatures, a membrane with an ionic conductivity of 0.066S/cm at 200 degrees C was newly developed. (NEDO)

  11. Understanding Net Zero Energy Buildings

    DEFF Research Database (Denmark)

    Salom, Jaume; Widén, Joakim; Candanedo, José

    2011-01-01

    Although several alternative definitions exist, a Net-Zero Energy Building (Net ZEB) can be succinctly described as a grid-connected building that generates as much energy as it uses over a year. The “net-zero” balance is attained by applying energy conservation and efficiency measures...... and by incorporating renewable energy systems. While based on annual balances, a complete description of a Net ZEB requires examining the system at smaller time-scales. This assessment should address: (a) the relationship between power generation and building loads and (b) the resulting interaction with the power grid...

  12. Net energy benefits of carbon nanotube applications

    International Nuclear Information System (INIS)

    Zhai, Pei; Isaacs, Jacqueline A.; Eckelman, Matthew J.

    2016-01-01

    Highlights: • Life cycle net energy benefits are examined. • CNT-enabled and the conventional technologies are compared. • Flash memory with CNT switches show significant positive net energy benefit. • Lithium-ion batteries with MWCNT cathodes show positive net energy benefit. • Lithium-ion batteries with SWCNT anodes tend to exhibit negative net energy benefit. - Abstract: Implementation of carbon nanotubes (CNTs) in various applications can reduce material and energy requirements of products, resulting in energy savings. However, processes for the production of carbon nanotubes (CNTs) are energy-intensive and can require extensive purification. In this study, we investigate the net energy benefits of three CNT-enabled technologies: multi-walled CNT (MWCNT) reinforced cement used as highway construction material, single-walled CNT (SWCNT) flash memory switches used in cell phones and CNT anodes and cathodes used in lithium-ion batteries used in electric vehicles. We explore the avoided or additional energy requirement in the manufacturing and use phases and estimate the life cycle net energy benefits for each application. Additional scenario analysis and Monte Carlo simulation of parameter uncertainties resulted in probability distributions of net energy benefits, indicating that net energy benefits are dependent on the application with confidence intervals straddling the breakeven line in some cases. Analysis of simulation results reveals that SWCNT switch flash memory and MWCNT Li-ion battery cathodes have statistically significant positive net energy benefits (α = 0.05) and SWCNT Li-ion battery anodes tend to have negative net energy benefits, while positive results for MWCNT-reinforced cement were significant only under an efficient CNT production scenario and a lower confidence level (α = 0.1).

  13. Energy indicators for electricity production : comparing technologies and the nature of the indicators Energy Payback Ratio (EPR), Net Energy Ratio (NER) and Cumulative Energy Demand (CED). [Oestfoldforskning AS

    Energy Technology Data Exchange (ETDEWEB)

    Raadal, Hanne Lerche [Ostfold research, Fredrikstad (Norway); Modahl, Ingunn Saur [Ostfold research, Fredrikstad (Norway); Bakken, Tor Haakon [SINTEF Energy, Trondheim (Norway)

    2012-11-01

    CEDREN (Centre for Environmental Design of Renewable Energy) is founded by The Research Council of Norway and energy companies and is one of eight centres that were part of the scheme Centre for Environment-friendly Energy Research (FME) when the scheme was launched in 2009. The main objective of CEDREN is to develop and communicate design solutions for transforming renewable energy sources to the desired energy products, and at the same time address the environmental and societal challenges at local, regional, national and global levels. CEDREN's board initiated in 2011 a pilot project on the topics 'Energy Pay-back Ratio (EPR)', 'Ecosystem services' and 'multi-criteria analysis (MCA)' in order to investigate the possible use of these concepts/indices in the management of regulated river basins and as tools to benchmark strategies for the development of energy projects/resources. The energy indicator part (documented in this report) has aimed at reviewing the applicability of different energy efficiency indicators, as such, in the strategic management and development of energy resources, and to compare and benchmark technologies for production of electricity. The main findings from this pilot study is also reported in a policy memo (in Norwegian), that is available at www.cedren.no. The work carried out in this project will be continued in the succeeding research project EcoManage, which was granted by the Research Council of Norway's RENERGI programme in December 2011. Energy indicators: Several energy indicators for extraction and delivery of an energy product (e.g. transport fuel, heat, electricity etc.) exist today. The main objective of such indicators is to give information about the energy efficiency of the needed extraction and transforming processes throughout the value chain related to the delivered energy product. In this project the indicators Energy Payback Ratio (EPR), Net Energy Ration (NER) and Cumulative

  14. On Productions of Net-Baryons in Central Au-Au Collisions at RHIC Energies

    Directory of Open Access Journals (Sweden)

    Ya-Hui Chen

    2015-01-01

    Full Text Available The transverse momentum and rapidity distributions of net-baryons (baryons minus antibaryons produced in central gold-gold (Au-Au collisions at 62.4 and 200 GeV are analyzed in the framework of a multisource thermal model. Each source in the model is described by the Tsallis statistics to extract the effective temperature and entropy index from the transverse momentum distribution. The two parameters are used as input to describe the rapidity distribution and to extract the rapidity shift and contribution ratio. Then, the four types of parameters are used to structure some scatter plots of the considered particles in some three-dimensional (3D spaces at the stage of kinetic freeze-out, which are expected to show different characteristics for different particles and processes. The related methodology can be used in the analyses of particle production and event holography, which are useful for us to better understand the interacting mechanisms.

  15. Net energy from nuclear power

    International Nuclear Information System (INIS)

    Rotty, R.M.; Perry, A.M.; Reister, D.B.

    1975-11-01

    An analysis of net energy from nuclear power plants is dependent on a large number of variables and assumptions. The energy requirements as they relate to reactor type, concentration of uranium in the ore, enrichment tails assays, and possible recycle of uranium and plutonium were examined. Specifically, four reactor types were considered: pressurized water reactor, boiling water reactor, high temperature gas-cooled reactor, and heavy water reactor (CANDU). The energy requirements of systems employing both conventional (current) ores with uranium concentration of 0.176 percent and Chattanooga Shales with uranium concentration of 0.006 percent were determined. Data were given for no recycle, uranium recycle only, and uranium plus plutonium recycle. Starting with the energy requirements in the mining process and continuing through fuel reprocessing and waste storage, an evaluation of both electrical energy requirements and thermal energy requirements of each process was made. All of the energy, direct and indirect, required by the processing of uranium in order to produce electrical power was obtained by adding the quantities for the individual processes. The energy inputs required for the operation of a nuclear power system for an assumed life of approximately 30 years are tabulated for nine example cases. The input requirements were based on the production of 197,100,000 MWH(e), i.e., the operation of a 1000 MW(e) plant for 30 years with an average plant factor of 0.75. Both electrical requirements and thermal energy requirements are tabulated, and it should be emphasized that both quantities are needed. It was found that the electricity generated far exceeded the energy input requirements for all the cases considered

  16. Energy potential, energy ratios, and the amount of net energy in Finnish field crop production; Peltobioenergian tuotanto Suomessa. Potentiaali, energiasuhteet ja nettoenergia

    Energy Technology Data Exchange (ETDEWEB)

    Mikkola, H.

    2012-11-01

    Energy potential, energy ratios, and the amount of net energy in Finnish field crop production were studied in this thesis. Special attention was paid to indirect energy inputs and how to treat them in energy analysis. Manufacturing of machines and agrochemicals and production of seeds are examples of indirect energy inputs.The bioenergy potential of the Finnish field crop production could be as large as 12 - 22 TWh, or 3 - 5% of the total energy consumption in Finland in 2008. The major part of this energy would originate from straw and biomass like reed canary grass cultivated for energy use. However, only 0.5 TWh of the potential is utilized. The output/input energy ratios of the studied field crops varied from 3 to 18, being highest (18) for reed canary grass and second highest (7) for sugar beet and grass cultivated for silage. The energy ratio of cereals and oil seed crops varied from 3 to 5 if only the yield of seeds was considered. If the yield of straw and stems was also taken into account the energy ratios would have been almost twofold. The energy ratios for Finnish wheat and barley were as high as those gained in Italian and Spanish conditions, respectively. However, the energy ratios of maize, elephant grass and giant reed were even over 50 in Central and Southern Europe. Plants that use the C4 photosynthesis pathway and produce high biomass yields thrive best in warm and sunny climate conditions. They use nitrogen and water more sparingly than C3 plants typically thriving in the cooler part of the temperate zone. When evaluating energy ratios for field crops it should be kept in mind that the maximal energy potential of the energy crop is the heating value of the dry matter at the field gate. Transportation of the crop and production of liquid fuels and electricity from biomass lowers the energy ratio. A comparison of field energy crops to a reforested field suggested that fast growing trees, as hybrid aspen and silver birch, would yield almost as

  17. Net positive energy buildings

    International Nuclear Information System (INIS)

    Romero, A.; Barreiro, E.; Sanchez Zabala, V.

    2010-01-01

    Buildings are great consumers of energy, being responsible for almost 36% of CO2 emissions in Europe. Though there are many initiatives towards the reduction of energy consumption and CO2 emissions in buildings, many of the alternatives are diminished due to a lack of a unique and holistic approach to the problem. This paper reports a new innovative concept of Positive Energy Buildings (EB+), as well as an integral methodology that covers the overall design process for achieving them. The methodology evaluates energy efficiency solutions at different scales, from building site to generation systems. An educational building design in Navarra serves as a case study to check the feasibility of the proposed methodology. The study concludes that the key to achieve a Positive Energy Building is a minimized energy demand, complemented by efficient facilities and enhanced by distributed power generation from renewable sources. (Author).

  18. Additively Manufactured, Net Shape Powder Metallurgy Cans for Valves Used in Energy Production

    Energy Technology Data Exchange (ETDEWEB)

    Peter, William H. [ORNL; Gandy, David [Electric Power Research Institute (EPRI); Lannom, Robert [Oak Ridge National Laboratory (ORNL)

    2018-01-01

    This CRADA NFE-14-05241 was conducted as a Technical Collaboration project within the Oak Ridge National Laboratory (ORNL) Manufacturing Demonstration Facility (MDF) sponsored by the US Department of Energy Advanced Manufacturing Office (CPS Agreement Number 24761). Opportunities for MDF technical collaborations are listed in the announcement “Manufacturing Demonstration Facility Technology Collaborations for US Manufacturers in Advanced Manufacturing and Materials Technologies” posted at http://web.ornl.gov/sci/manufacturing/docs/FBO-ORNL-MDF-2013-2.pdf. The goal of technical collaborations is to engage industry partners to participate in short-term, collaborative projects within the Manufacturing Demonstration Facility (MDF) to assess applicability and of new energy efficient manufacturing technologies. Research sponsored by the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Advanced Manufacturing Office, under contract DE-AC05-00OR22725 with UT-Battelle, LLC.ORNL would like to acknowledge the leadership of EPRI in pulling together the extensive team and managing the execution of the project. In addition, ORNL would like to acknowledge the other contributions of the team members associated with this project. Quintus provided time, access, expertise, and labor of their hydro forming capabilities to evaluate both conventional and additively manufactured tools through this process. Crane ChemPharma Energy provided guidance and information on valve geometries. Carpenter Powder Products was involved with the team providing information on powder processing as it pertains to the canning and hot isostatic pressing of powder. on providing powder and knowledge as it pertains to powder supply for hot isostatic pressing; they also provided powder for the test trials by the industrial team. Bodycote provided guidance on hot isostatic pressing and can requirements. They were also responsible for the hot isostatic pressing of the test valve

  19. Excess heat production of future net zero energy buildings within district heating areas in Denmark

    DEFF Research Database (Denmark)

    Nielsen, Steffen; Möller, Bernd

    2012-01-01

    Denmark’s long-term energy goal is to develop an energy system solely based on renewable energy sources by 2050. To reach this goal, energy savings in buildings is essential. Therefore, the focus on energy efficient measures in buildings and netzeroenergybuildings (NZEBs) has increased. Most...

  20. An optimization methodology for the design of renewable energy systems for residential net zero energy buildings with on-site heat production

    DEFF Research Database (Denmark)

    Milan, Christian; Bojesen, Carsten; Nielsen, Mads Pagh

    2011-01-01

    The concept of net zero energy buildings (NZEB) has received increased attention throughout the last years. A well adapted and optimized design of the energy supply system is crucial for the performance of such buildings. This paper aims at developing a method for the optimal sizing of renewable...... energy supply systems for residential NZEB involving on-site production of heat and electricity in combination with electricity exchanged with the public grid. The model is based on linear programming and determines the optimal capacities for each relevant supply technology in terms of the overall system...

  1. Conceptual net energy output for biofuel production from lignocellulosic biomass through biorefining

    Science.gov (United States)

    J.Y. Zhu; X.S. Zhuang

    2012-01-01

    There is a lack of comprehensive information in the retrievable literature on pilot scale process and energy data using promising process technologies and commercially scalable and available capital equipment for lignocellulosic biomass biorefining. This study conducted a comprehensive review of the energy efficiency of selected sugar platform biorefinery process...

  2. HANPP Collection: Global Patterns in Net Primary Productivity (NPP)

    Data.gov (United States)

    National Aeronautics and Space Administration — The Global Patterns in Net Primary Productivity (NPP) portion of the HANPP Collection maps the net amount of solar energy converted to plant organic matter through...

  3. Global patterns in human consumption of net primary production

    Science.gov (United States)

    Imhoff, Marc L.; Bounoua, Lahouari; Ricketts, Taylor; Loucks, Colby; Harriss, Robert; Lawrence, William T.

    2004-06-01

    The human population and its consumption profoundly affect the Earth's ecosystems. A particularly compelling measure of humanity's cumulative impact is the fraction of the planet's net primary production that we appropriate for our own use. Net primary production-the net amount of solar energy converted to plant organic matter through photosynthesis-can be measured in units of elemental carbon and represents the primary food energy source for the world's ecosystems. Human appropriation of net primary production, apart from leaving less for other species to use, alters the composition of the atmosphere, levels of biodiversity, energy flows within food webs and the provision of important ecosystem services. Here we present a global map showing the amount of net primary production required by humans and compare it to the total amount generated on the landscape. We then derive a spatial balance sheet of net primary production `supply' and `demand' for the world. We show that human appropriation of net primary production varies spatially from almost zero to many times the local primary production. These analyses reveal the uneven footprint of human consumption and related environmental impacts, indicate the degree to which human populations depend on net primary production `imports' and suggest policy options for slowing future growth of human appropriation of net primary production.

  4. Net energy gain from DT fusion

    International Nuclear Information System (INIS)

    Buende, R.

    1985-01-01

    The net energy which can be gained from an energy raw material by means of a certain conversion system is deduced as the figure-of-merit which adequately characterizes the net energy balance of utilizing an energy source. This potential net energy gain is determined for DT fusion power plants. It is represented as a function of the degree of exploitation of the energy raw material lithium ore and is compared with the net energy which can be gained with LW and FBR power plants by exploiting uranium ore. The comparison clearly demonstrates the net energetic advantage of DT fusion. A sensitivity study shows that this holds even if the energy expenditure for constructing and operating is drastically increased

  5. Net energy from nuclear power

    International Nuclear Information System (INIS)

    Perry, A.M.; Rotty, R.M.; Reister, D.B.

    1977-01-01

    Non-fission energy inputs to nuclear fuel cycles were calculated for four types of power reactors and for two grades of uranium ore. Inputs included all requirements for process operations, materials, and facility construction. Process stages are mining, milling, uranium conversion, enrichment, fuel fabrication, reprocessing, waste disposal, reactor construction and operation, and all transportation. Principal inputs were analyzed explicitly; small contributions and facility construction were obtained from input-output tables. For major facilities, the latter approach was based on disaggregated descriptions. Enrichment energy was that of U.S. diffusion plants, with uranium tails assay retained as a variable parameter. Supplemental electrical requirements, as a percentage of lifetime electrical output, are 5-6% for LWRs (0.3 - 0.2% tails assay) using ores with 0.2% uranium and without recycle. Recycle of uranium and plutonium reduces the electrical requirements 30%. Chattanooga Shales (0.006% U) require one-third more electricity. Thermal energy requirements are about 5% of electrical output with conventional ores; shales raise this to about 14%, with 0.2% enrichment tails and full recycle. About one-tenth of the electrical supplements and about a third of the thermal energy supplements are required prior to operation. A typical LWR will repay its energy loan within 15 months, allowing for low initial load factors. Enrichment requiring only 10% as much separative work as gaseous diffusion would reduce electrical requirements about 80%, but have little effect on thermal energy inputs. HTGRs require slightly less supplemental energy than LWRs. HWRs (with natural uranium) require about one-third as much supplemental electricity, but half again as much thermal energy, largely for heavy water production. The paper presents detailed data for several combinations of reactor type, ore grade and tails assay and compares them with conventional power plants. It also exhibits

  6. Defining net zero energy buildings

    CSIR Research Space (South Africa)

    Jonker Klunne, W

    2013-01-01

    Full Text Available Worldwide increasing attention to energy consumption and associated environmental impacts thereof has resulted in a critical attitude towards energy usage of building. Increasing costs of energy and dependence on energy service providers add...

  7. HANPP Collection: Human Appropriation of Net Primary Productivity as a Percentage of Net Primary Productivity

    Data.gov (United States)

    National Aeronautics and Space Administration — The Human Appropriation of Net Primary Productivity (HANPP) as a Percentage of Net Primary Product (NPP) portion of the HANPP Collection represents a map identifying...

  8. Re-assessment of net energy production and greenhouse gas emissions avoidance after 40 years of photovoltaics development

    NARCIS (Netherlands)

    Louwen, Atse|info:eu-repo/dai/nl/375268456; Van Sark, Wilfried G J H M|info:eu-repo/dai/nl/074628526; Faaij, André P C; Schropp, Ruud E I|info:eu-repo/dai/nl/072502584

    2016-01-01

    Since the 1970s, installed solar photovoltaic capacity has grown tremendously to 230 gigawatt worldwide in 2015, with a growth rate between 1975 and 2015 of 45%. This rapid growth has led to concerns regarding the energy consumption and greenhouse gas emissions of photovoltaics production. We

  9. Anaerobic digestion for methane generation and ammonia reforming for hydrogen production: A thermodynamic energy balance of a model system to demonstrate net energy feasibility

    International Nuclear Information System (INIS)

    Babson, David M.; Bellman, Karen; Prakash, Shaurya; Fennell, Donna E.

    2013-01-01

    During anaerobic digestion, organic matter is converted to carbon dioxide and methane, and organic nitrogen is converted to ammonia. Generally, ammonia is recycled as a fertilizer or removed via nitrification–denitrification in treatment systems; alternatively it could be recovered and catalytically converted to hydrogen, thus supplying additional fuel. To provide a basis for further investigation, a theoretical energy balance for a model system that incorporates anaerobic digestion, ammonia separation and recovery, and conversion of the ammonia to hydrogen is reported. The model Anaerobic Digestion-Bioammonia to Hydrogen (ADBH) system energy demands including heating, pumping, mixing, and ammonia reforming were subtracted from the total energy output from methane and hydrogen to create an overall energy balance. The energy balance was examined for the ADBH system operating with a fixed feedstock loading rate with C:N ratios (gC/gN) ranging from 136 to 3 which imposed corresponding total ammonia nitrogen (TAN) concentrations of 20–10,000 mg/L. Normalizing total energy potential to the methane potential alone indicated that at a C:N ratio of 17, the energy output was greater for the ADBH system than from anaerobic digestion generating only methane. Decreasing the C:N ratio increased the methane content of the biogas comprising primarily methane to >80% and increased the ammonia stripping energy demand. The system required 23–34% of the total energy generated as parasitic losses with no energy integration, but when internally produced heat and pressure differentials were recovered, parasitic losses were reduced to between 8 and 17%. -- Highlights: •Modeled an integrated Anaerobic Digestion-Bioammonia to Hydrogen (ADBH) system. •Demonstrated positive net energy produced over a range of conditions by ADBH. •Demonstrated significant advantages of dual fuel recovery for energy gain by >20%. •Suggested system design considerations for energy recovery with

  10. Using net energy output as the base to develop renewable energy

    International Nuclear Information System (INIS)

    Shaw Daigee; Hung Mingfeng; Lin Yihao

    2010-01-01

    In order to increase energy security, production of renewable energies has been highly promoted by governments around the world in recent years. The typical base of various policy instruments used for this purpose is gross energy output of renewable energy. However, we show that basing policy instruments on gross energy output will result in problems associated with energy waste, economic inefficiency, and negative environmental effects. We recommend using net energy output as the base to apply price or quantity measures because it is net energy output, not gross energy output, which contributes to energy security. The promotion of gross energy output does not guarantee a positive amount of net energy output. By basing policy instruments on net energy output, energy security can be enhanced and the above mentioned problems can be avoided.

  11. HANPP Collection: Global Patterns in Net Primary Productivity (NPP)

    Data.gov (United States)

    National Aeronautics and Space Administration — The Global Patterns in Net Primary Productivity (NPP) portion of the Human Appropriation of Net Primary Productivity (HANPP) Collection maps the net amount of solar...

  12. Net energy analysis - powerful tool for selecting elective power options

    Energy Technology Data Exchange (ETDEWEB)

    Baron, S. [Brookhaven National Laboratory, Upton, NY (United States)

    1995-12-01

    A number of net energy analysis studies have been conducted in recent years for electric power production from coal, oil and uranium fuels; synthetic fuels from coal and oil shale; and heat and electric power from solar energy. This technique is an excellent indicator of investment costs, environmental impact and potential economic competitiveness of alternative electric power systems for energy planners from the Eastern European countries considering future options. Energy conservation is also important to energy planners and the net energy analysis technique is an excellent accounting system on the extent of energy resource conservation. The author proposes to discuss the technique and to present the results of his studies and others in the field. The information supplied to the attendees will serve as a powerful tool to the energy planners considering their electric power options in the future.

  13. Calculation Tool for Determining the Net Energy Gain

    DEFF Research Database (Denmark)

    Laustsen, Jacob Birck; Svendsen, Svend

    2002-01-01

    is dependent on both the U-values and the g-values. Beyond this it is dependent on the orientation of the windows and the climate and the actual period. This makes it difficult to choose the glazings and windows that are optimal with regard to energy performance in a given case. These facts have aroused a need...... for simple and accurate methods to determine and compare the energy performance of different window products. When choosing windows for new buildings or retrofitting a calculation tool that in a simple way determines the net energy gain from the specific windows in the actual building will ease the selection...... of the best window solution. Such a tool combined with a database with window products can make calculations of the heat loss or energy demand corresponding to the requirements in the new building code easier and more correct. In the paper, methods to determine energy performance data and the net energy gain...

  14. Energy performance of windows based on the net energy gain

    DEFF Research Database (Denmark)

    Svendsen, Svend; Kragh, Jesper; Laustsen, Jacob Birck

    2005-01-01

    The paper presents a new method to set up energy performance requirements and energy classes for windows of all dimensions and configurations. The net energy gain of windows is the solar gain minus the heat loss integrated over the heating season. The net energy gain can be calculated for one...... be expressed as a function of two parameters representing the energy performance and two parameters representing the geometry of the window. The two energy performance parameters are the net energy gain per area of the glazing unit and the sum of the heat losses through the frame and the assembly per length...... of the frame. The two geometry numbers are the area of the glazing unit relative to the window area and the length of the frame profiles relative to the window area. Requirements and classes for the energy performance of the window can be given by assigning values to the two energy performance parameters...

  15. International Clean Energy System Using Hydrogen Conversion (WE-NET). subtask 4. Development of hydrogen production technology; Suiso riyo kokusai clean energy system gijutsu (WE-NET). subtask 4. Suiso seizo gijutsu no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    This paper describes development of hydrogen production technology as a part of the WE-NET project. For the solid polymer water electrolysis method higher in efficiency and lower in cost than the previous methods, 5 companies have developed element technologies for improving electrolysis cells and synthesis technologies of hot solid polymer electrolyte based on each proper catalyst electrode production method. In fiscal 1996, the initial study on large-scale systems by middle laboratory cells was made as well as improvement of electrolysis performance by small laboratory cells and endurance tests. Among the previous methods such as a hot press method (bonding of an ion exchange membrane to an electrode), an electroless plating method (preparation of porous surface onto a membrane electrode assembly), a zero gap method (preparation of high-efficiency high-current density cells), and a sintered porous electrode method (carrying of the mixture of catalytic powder and ion exchange resin-dissipated solution onto sintered metallic porous electrode surface), the former two methods were adopted for development of bench-scale cells as effective promising methods. 192 refs., 183 figs., 108 tabs.

  16. EVo: Net Shape RTM Production Line

    Directory of Open Access Journals (Sweden)

    Sven Torstrick

    2016-04-01

    Full Text Available EVo research platform is operated by the Center for Lightweight-Production-Technology of the German Aerospace Center in Stade. Its objective is technology demonstration of a fully automated RTM (Resin Transfer Molding production line for composite parts in large quantities. Process steps include cutting and ply handling, draping, stacking, hot-forming, preform-trimming to net shape, resin injection, curing and demolding.

  17. Analysis of Squid Net Fisheries Business Production

    Directory of Open Access Journals (Sweden)

    Herna Octivia Damayanti

    2017-03-01

    Full Text Available Squid net is one of alternatives to replace trawl net in Pati regency. The purposes of the research are 1 to determine the influence factors, 2 to analyze the return to scale, 3 to analyze cost and return.The research location in Juwana Subdistrict particularly Bakaran Kulon, Dukutalit, Bajomulyo and Bendar Villages. The research conducted on October 2015 to June 2016. The number of final samples was 36, while the formulation of management strategies used 15 samples by snowball sampling. Data analysis techniques used 1 Cobb Douglas production function, 2 revenue-cost ratio analysis. The results of the research are 1 significant inputs for production factor are long trip, Solar fuel, the number of crew and lights. 2 the return to scale of squid net bussiness in Juwana subdistrict Pati regency is -0.231 means decreasing to scale. 3 the R/C ratio of scenario II more profitable for squid net crews than  scenario I.

  18. Net-Zero Energy Technical Shelter

    DEFF Research Database (Denmark)

    Zhang, Chen; Heiselberg, Per; Jensen, Rasmus Lund

    2014-01-01

    Technical shelters are the basic structures for storing electronic and technical equipment, and commonly used for telecommunication base station, windmill, gas station, etc. Due to their high internal heat load density and special operation schedule, they consume more energy than normal residential...... or commercial buildings. On the other hand, it is a big challenge to power the technical shelter in remote area where the grids are either not available or the expansion of grid is expensive. In order to minimize the energy consumption and obtain a reliable and cost-efficient power solution for technical...... shelter, this study will apply the net-zero energy concept into the technical shelter design. The energy conservation can be achieved by proper design of building envelop and optimization of the cooling strategies. Both experiments and numerical simulations are carried out to investigate the indoor...

  19. Energy balance framework for Net Zero Energy buildings

    Science.gov (United States)

    Approaching a Net Zero Energy (NZE) building goal based on current definitions is flawed for two principal reasons - they only deal with energy quantities required for operations, and they do not establish a threshold, which ensures that buildings are optimized for reduced consum...

  20. A Conversation on Zero Net Energy Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Eley, Charles; Gupta, Smita; Torcellini, Paul; Mchugh, Jon; Liu, Bing; Higgins, Cathy; Iplikci, Jessica; Rosenberg, Michael I.

    2017-06-30

    The submitted Roundtable discussion covers zero net energy (ZNE) buildings and their expansion into the market as a more widely adopted approach for various building types and sizes. However, the market is still small, and this discussion brings together distinguished researchers, designers, policy makers, and program administrations to represent the key factors making ZNE building more widespread and mainstream from a broad perspective, including governments, utilities, energy-efficiency research institutes, and building owners. This roundtable was conducted by the ASHRAE Journal with Bing Liu, P.E., Member ASHRAE, Charles Eley, FAIA, P.E., Member ASHRAE; Smita Gupta, Itron; Cathy Higgins, New Buildings Institute; Jessica Iplikci, Energy Trust of Oregon; Jon McHugh, P.E., Member ASHRAE; Michael Rosenberg, Member ASHRAE; and Paul Torcellini, Ph.D., P.E., NREL.

  1. Net-Zero Building Technologies Create Substantial Energy Savings -

    Science.gov (United States)

    only an estimated 1% of commercial buildings are built to net-zero energy criteria. One reason for this Continuum Magazine | NREL Net-Zero Building Technologies Create Substantial Energy Savings Net -Zero Building Technologies Create Substantial Energy Savings Researchers work to package and share step

  2. Human appropriation of net primary production in the United Kingdom, 1800-2000. Changes in society's impact on ecological energy flows during the agrarian-industrial transition

    International Nuclear Information System (INIS)

    Musel, Annabella

    2009-01-01

    This paper presents an empirical analysis of the United Kingdom's society's long-term intervention into the energy flows of domestic terrestrial ecosystems through the human appropriation of aboveground net primary production (aHANPP) covering the period 1800-2000. The depicted aHANPP trajectory and the historical development of its components are discussed in view of a continuously increasing population and the transition process from an agrarian to an industrial socioecological regime. During the 19th century, aHANPP shows a steady decline from its level of 71% in 1800. While even higher levels were reached during the mid 20th century, the trend during the last forty years of the period under investigation again shows a reduction of aHANPP, which lies at 68% in the year 2000. The high values of aHANPP in the United Kingdom are primarily attributable to the limited amount of forest in comparison to large agricultural areas. At the beginning of the studied period, the relative stabilisation or even decrease in aHANPP in comparison to population development was made possible through the area expansion of and productivity increases on cropland and permanent pastures. Later this was made possible through the outsourcing of biomass harvest, by satisfying local nutritional demands by means of overseas imports, and as from the mid 20th century through huge amounts of fossil fuel based inputs into agriculture (e.g. increased amounts of fertilizers and motorized traction) which allowed increases in biomass harvest to be decoupled from HANPP. (author)

  3. Energy balance of algal biomass production in a 1-ha “Green Wall Panel” plant: How to produce algal biomass in a closed reactor achieving a high Net Energy Ratio

    International Nuclear Information System (INIS)

    Tredici, M.R.; Bassi, N.; Prussi, M.; Biondi, N.; Rodolfi, L.; Chini Zittelli, G.; Sampietro, G.

    2015-01-01

    Highlights: • Tetraselmis suecica production in a 1-ha GWP plant in Tuscany (Italy) has a NER < 1. • Major energy costs are embodied energy of GWP and mixing. • In a suitable location (North Africa) the NER increases by 40%. • Integration of photovoltaic in the GWP allows to achieve a NER of 1.7. • T. suecica cultivated in a GWP plant can yield up to 30 t of protein ha −1 year −1 . - Abstract: The annual productivity of Tetraselmis suecica in a 1-ha Green Wall Panel-II (GWP-II) plant in Tuscany (Italy) is 36 t (dry weight) ha −1 year −1 , which corresponds to an energy output of 799 GJ ha −1 year −1 . The energy inputs necessary to attain that productivity amount to 1362 GJ ha −1 year −1 , mainly given by the embodied energy of the reactor (about 30%), mixing (about 40%), fertilizers (11%) and harvesting (10%). The Net Energy Ratio (NER) of T. suecica production is thus 0.6. In a more suitable location (North Africa) productivity nearly doubles, reaching 66 t ha −1 year −1 , but the NER increases only by 40% and the gain (difference between output and inputs) remains negative. In a GWP-II integrated with photovoltaics (PV), the NER becomes 1.7 and the gain surpasses 600 GJ ha −1 year −1 . Marine microalgae cultivation in a GWP plant, in a suitable location, can attain high biomass productivities and protein yields 30 times higher than those achievable with traditional crops (soya). When the GWP reactor is integrated with PV, the process attains a positive energy balance, which substantially enhances its sustainability

  4. Net energy analysis in a Ramsey–Hotelling growth model

    International Nuclear Information System (INIS)

    Macías, Arturo; Matilla-García, Mariano

    2015-01-01

    This article presents a dynamic growth model with energy as an input in the production function. The available stock of energy resources is ordered by a quality parameter based on energy accounting: the “Energy Return on Energy Invested” (EROI). In our knowledge this is the first paper where EROI fits in a neoclassical growth model (with individual utility maximization and market equilibrium), establishing the economic use of “net energy analysis” on a firmer theoretical ground. All necessary concepts to link neoclassical economics and EROI are discussed before their use in the model, and a comparative static analysis of the steady states of a simplified version of the model is presented. - Highlights: • A neoclassical growth model with EROI (“Energy Return on Energy Invested”) is shown • All concepts linking neoclassical economics and net energy analysis are discussed • Any EROI decline can be compensated increasing gross activity in the energy sector. • The economic impact of EROI depends on some non-energy cost in the energy sector. • Comparative steady-state statics for different EROI levels is performed and discussed. • Policy implications are suggested.

  5. A Conversation on Zero Net Energy Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Torcellini, Paul A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Eley, Charles [Consultant; Gupta, Smita [Itron; McHugh, Jon [McHugh Energy Consultants; Lui, Bing [Pacific Northwest National Laboratory; Higgins, Cathy [New Buildings Institute; Iplikci, Jessica [Energy Trust of Oregon; Rosenberg, Michael [Pacific Northwest National Laboratory

    2017-06-01

    Recently, zero net energy (ZNE) buildings have moved from state-of-the-art small project demonstrations to a more widely adopted approach across the country among various building types and sizes. States such as California set policy goals of all new residential construction to be NZE by 2020 and all commercial buildings to be NZE by 2030. However, the market for designing, constructing, and operating ZNE buildings is still relatively small. We bring together distinguished experts to share their thoughts on making ZNE buildings more widespread and mainstream from a broad perspective, including governments, utilities, energy-efficiency research institutes, and building owners. This conversation also presents the benefits of ZNE and ways to achieve that goal in the design and operation of buildings. The following is a roundtable conducted by ASHRAE Journal and Bing Liu with Charles Eley, Smita Gupta, Cathy Higgins, Jessica Iplikci, Jon McHugh, Michael Rosenberg, and Paul Torcellini.

  6. WE-NET Hydrogen Energy Symposium proceedings; WE-NET suiso energy symposium koen yokoshu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-02-24

    The research and development of WE-NET (World Energy Network) was started in 1993 as a NEDO (New Energy and Industrial Technology Development Organization) project in the New Sunshine Program of Agency of Industrial Science and Technology, Ministry of International Trade and Industry, and aims to contribute to the improvement of global environment and to ease the difficult energy supply/demand situation. The ultimate goal of WE-NET is the construction of a global-scale clean energy network in which hydrogen will be produced from renewable energies such as water and sunshine for distribution to energy consuming locations. Experts are invited to the Symposium from the United States, Germany, and Canada. Information is collected from the participants on hydrogen energy technology development in the three countries, the result of the Phase I program of WE-NET is presented to hydrogen energy scientists in Japan, and views and opinions on the project are collected from them. Accommodated in the above-named publication are 30 essays and three special lectures delivered at the Symposium. (NEDO)

  7. Development of net energy ratio for quad-generation pathways

    DEFF Research Database (Denmark)

    Rudra, Souman; Rosendahl, Lasse; Kumar, Amit

    2012-01-01

    The conversion of biomass to four different outputs via gasification and catalytic methanation is a renewable technology that could reduce the use of fossil fuels and GHG emissions. This study investigates the energy aspects of producing electricity, heat, methanol and methane. The Gas Technology...... Institute (GTI) gasifier and Circulating Fluidized Bed (CFB) technologies are used for this quad generation process. Three different biomass feedstocks are considered in this study. The net energy ratio for six different pathways having the range of between 1.3–9.3. The lowest limit corresponds to the straw......-based power, heat, methanol and methane production pathway using GTI technology. Since more efficient alternatives exist for the generation of heat and electricity from biomass, it is argued that syngas is best used for methanol production. The aim of this study was to evaluate the energy performance...

  8. Body composition and net energy requirements of Brazilian Somali lambs

    Directory of Open Access Journals (Sweden)

    Elzânia S. Pereira

    2014-12-01

    Full Text Available The aim of this study was to determine the energy requirements for maintenance (NEm and growth of 48 Brazilian Somali ram lambs with an average initial body weight of 13.47±1.76 kg. Eight animals were slaughtered at the trials beginning as a reference group to estimate the initial empty body weight (EBW and body composition. The remaining animals were assigned to a randomised block design with eight replications per block and five diets with increasing metabolisable energy content (4.93, 8.65, 9.41, 10.12 and 11.24 MJ/kg dry matter. The logarithm of heat production was regressed against metabolisable energy intake (MEI, and the NEm (kJ/kg0.75 EBW/day were estimated by extrapolation, when MEI was set at zero. The NEm was 239.77 kJ/kg0.75 EBW/day. The animal’s energy and EBW fat contents increased from 11.20 MJ/kg and 208.54 g/kg to 13.54 MJ/kg and 274.95 g/kg of EBW, respectively, as the BW increased from 13 to 28.70 kg. The net energy requirements for EBW gain increased from 13.79 to 16.72 MJ/kg EBW gain for body weights of 13 and 28.70 kg. Our study indicated the net energy requirements for maintenance in Brazilian Somali lambs were similar to the values commonly recommended by the United States’ nutritional system, but lower than the values recommended by Agricultural Research Council and Commonwealth Scientific and Industrial Research Organization. Net requirements for weight gain were less compared to the values commonly recommended by nutritional system of the United States.

  9. Optimising building net energy demand with dynamic BIPV shading

    International Nuclear Information System (INIS)

    Jayathissa, P.; Luzzatto, M.; Schmidli, J.; Hofer, J.; Nagy, Z.; Schlueter, A.

    2017-01-01

    Highlights: •Coupled analysis of PV generation and building energy using adaptive BIPV shading. •20–80% net energy saving compared to an equivalent static system. •The system can in some cases compensate for the entire heating/cooling/lighting load. •High resolution radiation simulation including impacts of module self shading. -- Abstract: The utilisation of a dynamic photovoltaic system for adaptive shading can improve building energy performance by controlling solar heat gains and natural lighting, while simultaneously generating electricity on site. This paper firstly presents an integrated simulation framework to couple photovoltaic electricity generation to building energy savings through adaptive shading. A high-resolution radiance and photovoltaic model calculates the photovoltaic electricity yield while taking into account partial shading between modules. The remaining solar irradiation that penetrates the window is used in a resistance-capacitance building thermal model. A simulation of all possible dynamic configurations is conducted for each hourly time step, of which the most energy efficient configuration is chosen. We then utilise this framework to determine the optimal orientation of the photovoltaic panels to maximise the electricity generation while minimising the building’s heating, lighting and cooling demand. An existing adaptive photovoltaic facade was used as a case study for evaluation. Our results report a 20–80% net energy saving compared to an equivalent static photovoltaic shading system depending on the efficiency of the heating and cooling system. In some cases the Adaptive Solar Facade can almost compensate for the entire energy demand of the office space behind it. The control of photovoltaic production on the facade, simultaneously with the building energy demand, opens up new methods of building management as the facade can control both the production and consumption of electricity.

  10. Fiscal 1997 survey report. Subtask 4 (hydrogen utilization worldwide clean energy system technology) (WE-NET) (development of hydrogen production technology); 1997 nendo seika hokokusho. Suiso riyo kokusai clean energy system gijutsu (WE-NET) subtask 4 suiso seizo gijutsu no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-03-01

    As a WE-NET subtask, a study has been conducted of the solid polyelectrolyte water electrolysis method by which higher efficiency and lower cost hydrogen production is expected than in the conventional hydrogen production method. Production methods of electrode, electrolyte, etc. were studied. In the electroless plating method, the manufacturing process of membrane-electrode assemblies was realized in a large area of 2500 cm{sup 2} by the porous-surfaced method by studying manufacturing conditions for slurry membrane/membrane assembly/electroless plating processes. In the hot-press method, the refining degree and dispersibility of iridium dioxide powder were studied to improve characteristics of anode catalyst. A method was developed to form polyelectrolyte coatings homogeneously on the surface of electrode layer catalytic powder, and a large area of 2500 cm{sup 2} was realized. Beside the performance test using large single cells, FS was conducted to discuss optimum operating conditions and optimum structures of plants. Both methods indicated the performance exceeding the energy conversion efficiency of 90%, a WE-NET target, at current density of 1A/cm{sup 2} and electrolysis temperature of 80degC. A key was found to a bench-scale development (electrode area of 2500 cm{sup 2}, about 5 layers) to be planned in fiscal 1998. 136 figs., 50 tabs.

  11. The Solar Energy Trifecta: Solar + Storage + Net Metering | State, Local,

    Science.gov (United States)

    and Tribal Governments | NREL The Solar Energy Trifecta: Solar + Storage + Net Metering The Solar Energy Trifecta: Solar + Storage + Net Metering February 12, 2018 by Benjamin Mow Massachusetts (DPU) seeking an advisory ruling on the eligibility of pairing solar-plus-storage systems with current

  12. Valuing ecosystem services. A shadow price for net primary production

    International Nuclear Information System (INIS)

    Richmond, Amy; Kaufmann, Robert K.; Myneni, Ranga B.

    2007-01-01

    We analyze the contribution of ecosystem services to GDP and use this contribution to calculate an empirical price for ecosystem services. Net primary production is used as a proxy for ecosystem services and, along with capital and labor, is used to estimate a Cobb Douglas production function from an international panel. A positive output elasticity for net primary production probably measures both marketed and nonmarketed contributions of ecosystems services. The production function is used to calculate the marginal product of net primary production, which is the shadow price for ecosystem services. The shadow price generally is greatest for developed nations, which have larger technical scalars and use less net primary production per unit output. The rate of technical substitution indicates that the quantity of capital needed to replace a unit of net primary production tends to increase with economic development, and this rate of replacement may ultimately constrain economic growth. (author)

  13. Heat Mismatch of future Net Zero Energy Buildings within district heating areas in Denmark

    DEFF Research Database (Denmark)

    Nielsen, Steffen; Möller, Bernd

    The long-term goal for Denmark is to develop an energy system solely based on renewable energy sources (RES) in 2050. To reach this goal energy savings in buildings are essential. Therefore, a focus on energy efficient measures in buildings and net zero energy buildings (NZEBs) have increased...... systems enables them to send or receive energy from these systems. This is beneficial for NZEBs because even though they have an annual net exchange of zero, there is a temporal mismatch in regard to the energy consumption of buildings and the production from the renewable energy units added to them...

  14. Net energy analysis of different electricity generation systems

    International Nuclear Information System (INIS)

    1994-07-01

    This document is a report on the net energy analysis of nuclear power and other electricity generation systems. The main objectives of this document are: To provide a comprehensive review of the state of knowledge on net energy analysis of nuclear and other energy systems for electricity generation; to address traditional questions such as whether nuclear power is a net energy producer or not. In addition, the work in progress on a renewed application of the net energy analysis method to environmental issues is also discussed. It is expected that this work could contribute to the overall comparative assessment of different energy systems which is an ongoing activity at the IAEA. 167 refs, 9 figs, 5 tabs

  15. Net Farm Income Analysis of Maize Production in Gwagwalada Area ...

    African Journals Online (AJOL)

    Net Farm Income Analysis of Maize Production in Gwagwalada Area Council of Federal Capital Territory, Nigeria. OO Alabi, AAA Coker, ME Idegbesor. Abstract. This study examined net farm income of maize production in Gwagwalada Area Council of Federal Capital Territory. The specific objectives are to: identify the ...

  16. Load Matching and Grid Interaction of Net Zero Energy Buildings

    DEFF Research Database (Denmark)

    Voss, Karsten; Candanedo, José A.; Geier, Sonja

    2010-01-01

    of seasonal energy storage on-site. Even though the wording “Net Zero Energy Building” focuses on the annual energy balance, large differences may occur between solution sets in the amount of grid interaction needed to reach the goal. The paper reports on the analysis of example buildings concerning the load......“Net Zero Energy Building” has become a prominent wording to describe the synergy of energy efficient building and renewable energy utilization to reach a balanced energy budget over a yearly cycle. Taking into account the energy exchange with a grid infrastructure overcomes the limitations...... matching and grid interaction. Indices to describe both issues are proposed and foreseen as part of a harmonized definition framework. The work is part of subtask A of the IEA SHCP Task40/ECBCS Annex 52: “Towards Net Zero Energy Solar Buildings”....

  17. Net load forecasting for high renewable energy penetration grids

    International Nuclear Information System (INIS)

    Kaur, Amanpreet; Nonnenmacher, Lukas; Coimbra, Carlos F.M.

    2016-01-01

    We discuss methods for net load forecasting and their significance for operation and management of power grids with high renewable energy penetration. Net load forecasting is an enabling technology for the integration of microgrid fleets with the macrogrid. Net load represents the load that is traded between the grids (microgrid and utility grid). It is important for resource allocation and electricity market participation at the point of common coupling between the interconnected grids. We compare two inherently different approaches: additive and integrated net load forecast models. The proposed methodologies are validated on a microgrid with 33% annual renewable energy (solar) penetration. A heuristics based solar forecasting technique is proposed, achieving skill of 24.20%. The integrated solar and load forecasting model outperforms the additive model by 10.69% and the uncertainty range for the additive model is larger than the integrated model by 2.2%. Thus, for grid applications an integrated forecast model is recommended. We find that the net load forecast errors and the solar forecasting errors are cointegrated with a common stochastic drift. This is useful for future planning and modeling because the solar energy time-series allows to infer important features of the net load time-series, such as expected variability and uncertainty. - Highlights: • Net load forecasting methods for grids with renewable energy generation are discussed. • Integrated solar and load forecasting outperforms the additive model by 10.69%. • Net load forecasting reduces the uncertainty between the interconnected grids.

  18. Scaling net ecosystem production and net biome production over a heterogeneous region in the Western United States

    Science.gov (United States)

    D.P. Turner; W.D. Ritts; B.E. Law; W.B. Cohen; Z. Yan; T. Hudiburg; J.L. Campbell; M. Duane

    2007-01-01

    Bottom-up scaling of net ecosystem production (NEP) and net biome production (NBP) was used to generate a carbon budget for a large heterogeneous region (the state of Oregon, 2.5x105 km2 ) in the Western United States. Landsat resolution (30 m) remote sensing provided the basis for mapping land cover and disturbance history...

  19. Criteria for Definition of Net Zero Energy Buildings

    DEFF Research Database (Denmark)

    Sartori, Igor; Marszal, Anna Joanna; Napolitano, Assunta

    2010-01-01

    The idea of a Net Zero Energy Building (Net ZEB) is understood conceptually, as it is understood that the way a Net ZEB is defined affects significantly the way it is designed in order to achieve the goal. However, little agreement exists on a common definition; the term is used commercially...... without a clear understanding and countries are enacting policies and national targets based on the concept without a clear definition in place. This paper presents a harmonised framework for describing the relevant characteristics of Net ZEBs in a series of criteria. Evaluation of the criteria...... and selection of the related options becomes a methodology for elaborating sound Net ZEB definitions in a formal, systematic and comprehensive way, creating the basis for legislations and action plans to effectively achieve the political targets. The common denominator for the different possible Net ZEB...

  20. Targeting Net Zero Energy at Marine Corps Base Hawaii, Kaneohe Bay: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Burman, K.; Kandt, A.; Lisell, L.; Booth, S.

    2012-05-01

    This paper summarizes the results of an NREL assessment of Marine Corps Base Hawaii (MCBH), Kaneohe Bay to appraise the potential of achieving net zero energy status through energy efficiency, renewable energy, and hydrogen vehicle integration. In 2008, the U.S. Department of Defense's U.S. Pacific Command partnered with the U.S. Department of Energy's (DOE's) National Renewable Energy Laboratory (NREL) to assess opportunities for increasing energy security through renewable energy and energy efficiency at Hawaii military installations. DOE selected Marine Corps Base Hawaii (MCBH), Kaneohe Bay, to receive technical support for net zero energy assessment and planning funded through the Hawaii Clean Energy Initiative (HCEI). NREL performed a comprehensive assessment to appraise the potential of MCBH Kaneohe Bay to achieve net zero energy status through energy efficiency, renewable energy, and hydrogen vehicle integration. This paper summarizes the results of the assessment and provides energy recommendations. The analysis shows that MCBH Kaneohe Bay has the potential to make significant progress toward becoming a net zero installation. Wind, solar photovoltaics, solar hot water, and hydrogen production were assessed, as well as energy efficiency technologies. Deploying wind turbines is the most cost-effective energy production measure. If the identified energy projects and savings measures are implemented, the base will achieve a 96% site Btu reduction and a 99% source Btu reduction. Using excess wind and solar energy to produce hydrogen for a fleet and fuel cells could significantly reduce energy use and potentially bring MCBH Kaneohe Bay to net zero. Further analysis with an environmental impact and interconnection study will need to be completed. By achieving net zero status, the base will set an example for other military installations, provide environmental benefits, reduce costs, increase energy security, and exceed its energy goals and mandates.

  1. Examples of Nearly Net Zero Energy Buildings Through One-Step and Stepwise Retrofits

    DEFF Research Database (Denmark)

    Galiotto, Nicolas; Heiselberg, Per; Knudstrup, Mary-Ann

    2012-01-01

    This paper presents the review of eight single-family house retrofit projects. The main objective is to collect and classify several approaches to nearly net zero energy building retrofitting. The selection has been made on the capacity of reaching a nearly net zero energy level via a one......-step or stepwise retrofit process. The review work is part of a more global Ph.D. project and is used as one of the basement of the future research work. The considered approaches have been sorted in two categories. The first approach has a very high use of energy conservation measures and low use of renewable...... energy production measures. The second approach has a lower use of energy conservation measures (but still high compared to a traditional renovation) and a higher use of renewable energy production measures. A third approach to nearly net zero energy building renovation exists but has not been considered...

  2. Community Net Energy Metering: How Novel Policies Expand Benefits of Net Metering to Non-Generators

    Energy Technology Data Exchange (ETDEWEB)

    Rose, James; Varnado, Laurel

    2009-04-01

    As interest in community solutions to renewable energy grows, more states are beginning to develop policies that encourage properties with more than one meter to install shared renewable energy systems. State net metering policies are evolving to allow the aggregation of multiple meters on a customer’s property and to dissolve conventional geographical boundaries. This trend means net metering is expanding out of its traditional function as an enabling incentive to offset onsite customer load at a single facility. This paper analyzes community net energy metering (CNEM) as an emerging vehicle by which farmers, neighborhoods, and municipalities may more easily finance and reap the benefits of renewable energy. Specifically, it aims to compare and contrast the definition of geographical boundaries among different CNEM models and examine the benefits and limitations of each approach. As state policies begin to stretch the geographic boundaries of net metering, they allow inventive solutions to encourage renewable energy investment. This paper attempts to initiate the conversation on this emerging policy mechanism and offers recommendations for further development of these policies.

  3. Green net national product for the sustainability and social welfare

    OpenAIRE

    Mohajan, Haradhan

    2010-01-01

    This paper discusses the theory of green national accounting and, emphasizes on social welfare and sustainable accounting. Weitzman provides a foundation for net national product as the stationary equivalent of a wealth maximizing path when there is a constant interest rate and no exogenous technological progress. An attempt has been taken here to make the relationship with different incomes and green net national product, under no exogenous technological progress and a constant utility disco...

  4. Net-energy analysis of nuclear and wind power systems

    International Nuclear Information System (INIS)

    Tyner, G.T. Sr.

    1985-01-01

    The following question is addressed: can nuclear power and wind power (a form of solar energy) systems yield enough energy to replicate themselves out of their own energy and leave a residual of net energy in order to provide society with its needs and wants. Evidence is provided showing that there is a proportionality between the real monetary cost and energy inputs. The life-cycle, economic cost of the energy-transformation entity is the basis for calculating the amount of energy needed, as inputs, to sustain energy transformation. This study is unique as follows: others were based on preliminary cost and performance estimates. This study takes advantage of updated cost and performance data. Second, most prior studies did not include the energy cost of labor, government, and financial services, transmission and distribution, and overhead in arriving at energy inputs. This study includes all economic costs as a basis for calculating energy-input estimates. Both static (single-entity analysis) and dynamic (total systems over time) analyses were done and the procedures are shown in detail. It was found that the net-energy yield will be very small and most likely negative. System costs must be substantially lowered or efficiencies materially improved before these systems can become sources of enough net energy to drive the United States economic system at even the present level of economic output

  5. Calculating systems-scale energy efficiency and net energy returns: A bottom-up matrix-based approach

    International Nuclear Information System (INIS)

    Brandt, Adam R.; Dale, Michael; Barnhart, Charles J.

    2013-01-01

    In this paper we expand the work of Brandt and Dale (2011) on ERRs (energy return ratios) such as EROI (energy return on investment). This paper describes a “bottom-up” mathematical formulation which uses matrix-based computations adapted from the LCA (life cycle assessment) literature. The framework allows multiple energy pathways and flexible inclusion of non-energy sectors. This framework is then used to define a variety of ERRs that measure the amount of energy supplied by an energy extraction and processing pathway compared to the amount of energy consumed in producing the energy. ERRs that were previously defined in the literature are cast in our framework for calculation and comparison. For illustration, our framework is applied to include oil production and processing and generation of electricity from PV (photovoltaic) systems. Results show that ERR values will decline as system boundaries expand to include more processes. NERs (net energy return ratios) tend to be lower than GERs (gross energy return ratios). External energy return ratios (such as net external energy return, or NEER (net external energy ratio)) tend to be higher than their equivalent total energy return ratios. - Highlights: • An improved bottom-up mathematical method for computing net energy return metrics is developed. • Our methodology allows arbitrary numbers of interacting processes acting as an energy system. • Our methodology allows much more specific and rigorous definition of energy return ratios such as EROI or NER

  6. Optimizing Existing Multistory Building Designs towards Net-Zero Energy

    Directory of Open Access Journals (Sweden)

    Mohammad Y. AbuGrain

    2017-03-01

    Full Text Available Recent global developments in awareness and concerns about environmental problems have led to reconsidering built environment approaches and construction techniques. One of the alternatives is the principle of low/zero-energy buildings. This study investigates the potentials of energy savings in an existing multi-story building in the Mediterranean region in order to achieve net-zero energy as a solution to increasing fossil fuel prices. The Colored building at the Faculty of Architecture, Eastern Mediterranean University, Cyprus was chosen as a target of this study to be investigated and analyzed in order to know how energy efficiency strategies could be applied to the building to reduce annual energy consumption. Since this research objective is to develop a strategy to achieve net-zero energy in existing buildings, case study and problem solving methodologies were applied in this research in order to evaluate the building design in a qualitative manner through observations, in addition to a quantitative method through an energy modeling simulation to achieve desirable results which address the problems. After optimizing the building energy performance, an alternative energy simulation was made of the building in order to make an energy comparison analysis, which leads to reliable conclusions. These methodologies and the strategies used in this research can be applied to similar buildings in order to achieve net-zero energy goals.

  7. Predicting energy performance of a net-zero energy building: A statistical approach

    International Nuclear Information System (INIS)

    Kneifel, Joshua; Webb, David

    2016-01-01

    Highlights: • A regression model is applied to actual energy data from a net-zero energy building. • The model is validated through a rigorous statistical analysis. • Comparisons are made between model predictions and those of a physics-based model. • The model is a viable baseline for evaluating future models from the energy data. - Abstract: Performance-based building requirements have become more prevalent because it gives freedom in building design while still maintaining or exceeding the energy performance required by prescriptive-based requirements. In order to determine if building designs reach target energy efficiency improvements, it is necessary to estimate the energy performance of a building using predictive models and different weather conditions. Physics-based whole building energy simulation modeling is the most common approach. However, these physics-based models include underlying assumptions and require significant amounts of information in order to specify the input parameter values. An alternative approach to test the performance of a building is to develop a statistically derived predictive regression model using post-occupancy data that can accurately predict energy consumption and production based on a few common weather-based factors, thus requiring less information than simulation models. A regression model based on measured data should be able to predict energy performance of a building for a given day as long as the weather conditions are similar to those during the data collection time frame. This article uses data from the National Institute of Standards and Technology (NIST) Net-Zero Energy Residential Test Facility (NZERTF) to develop and validate a regression model to predict the energy performance of the NZERTF using two weather variables aggregated to the daily level, applies the model to estimate the energy performance of hypothetical NZERTFs located in different cities in the Mixed-Humid Climate Zone, and compares these

  8. HANPP Collection: Human Appropriation of Net Primary Productivity (HANPP) by Country and Product

    Data.gov (United States)

    National Aeronautics and Space Administration — The Global Patterns in Human Appropriation of Net Primary Productivity (HANPP) portion of the HANPP Collection represents a digital map of human appropriation of net...

  9. Targeting Net Zero Energy at Fort Carson: Assessment and Recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, K.; Markel, T.; Simpson, M.; Leahey, J.; Rockenbaugh, C.; Lisell, L.; Burman, K.; Singer, M.

    2011-10-01

    The U.S. Army's Fort Carson installation was selected to serve as a prototype for net zero energy assessment and planning. NREL performed the comprehensive assessment to appraise the potential of Fort Carson to achieve net zero energy status through energy efficiency, renewable energy, and electric vehicle integration. This report summarizes the results of the assessment and provides energy recommendations. This study is part of a larger cross-laboratory effort that also includes an assessment of renewable opportunities at seven other DoD Front Range installations, a microgrid design for Fort Carson critical loads and an assessment of regulatory and market-based barriers to a regional secure smart grid.

  10. Net energy levels on the lipid profile of pork

    Directory of Open Access Journals (Sweden)

    Stephan Alexander da Silva Alencar

    2017-09-01

    Full Text Available ABSTRACT: This study was conducted to evaluate the effects of net energy levels on the lipid profile of adipose tissue and muscle of swines. A total of 90 animals, with initial weight of 71.94±4.43kg, were used, and distributed in a randomized block design in five net energy levels (2,300, 2,425, 2,550, 2,675, and 2,800Kcal kg-1 feed, with nine replicates and two animals per experimental unit. Lipid profiles of adipose tissue and muscle were analyzed using gas chromatography. Increasing the levels of net energy using soybean oil, improved the lipid profile of adipose tissue and muscle, increased linearly (P<0.05 the concentrations of polyunsaturated fatty acids, especially linoleic and α-linolenic acid, reduced linearly (P<0.05 the monounsaturated and saturated fatty acids and omega 6: omega 3. In adipose tissue was observed linear reduction (P<0.05 of atherogenic and thrombogenic indexes. In conclusion, increasing the level of net energy of the diet using soybean oil improved the lipid profile of adipose tissue and muscle.

  11. A quantitative assessment of the determinants of the net energy value of biofuels

    International Nuclear Information System (INIS)

    Bureau, Jean-Christophe; Disdier, Anne-Celia; Gauroy, Christine; Treguer, David

    2010-01-01

    Many studies have investigated the net energy balance of biofuel products (in terms of savings on fossil fuels) and assessed the reductions in greenhouse gas emissions from substituting biofuels for fossil fuel. These studies provide very different results, with net balance ranging from highly positive to negative. Our study analyses a large sample of these studies by retrieving the main parameters used and converting them into units of measurement that are comparable. This information is used to unravel the main determinants of the differences in net energy value across studies. Our approach relies on descriptive statistics and econometric estimates based on a meta-analysis methodology. Our results suggest that the large variability across studies can be explained by the degree to which particular inputs (i.e. nitrogen, farm labor) are controlled for, and the way fossil energy consumption is allocated to the various co-products.

  12. Feasibility of Achieving a Zero-Net-Energy, Zero-Net-Cost Homes

    Energy Technology Data Exchange (ETDEWEB)

    Al-Beaini, S.; Borgeson, S.; Coffery, B.; Gregory, D.; Konis, K.; Scown, C.; Simjanovic, J.; Stanley, J.; Strogen, B.; Walker, I.

    2009-09-01

    A green building competition, to be known as the Energy Free Home Challenge (EFHC), is scheduled to be opened to teams around the world in 2010. This competition will encourage both design innovation and cost reduction, by requiring design entries to meet 'zero net energy' and 'zero net cost' criteria. For the purposes of this competition, a 'zero net energy' home produces at least as much energy as it purchases over the course of a year, regardless of the time and form of the energy (e.g., electricity, heat, or fuel) consumed or produced. A 'zero net cost' home is no more expensive than a traditional home of comparable size and comfort, when evaluated over the course of a 30-year mortgage. In other words, the 'green premium' must have a payback period less than 30 years, based on the value of energy saved. The overarching goal of the competition is to develop affordable, high-performance homes that can be mass-produced at a large scale, and are able to meet occupant needs in harsh climates (as can be found where the competition will be held in Illinois). This report outlines the goals of the competition, and gauges their feasibility using both modeling results and published data. To ensure that the established rules are challenging, yet reasonable, this report seeks to refine the competition goals after exploring their feasibility through case studies, cost projections, and energy modeling. The authors of this report conducted a survey of the most progressive home energy-efficiency practices expected to appear in competition design submittals. In Appendix A, a summary can be found of recent projects throughout the United States, Canada, Germany, Switzerland, Sweden and Japan, where some of the most progressive technologies have been implemented. As with past energy efficient home projects, EFHC competitors will incorporate a multitude of energy efficiency measures into their home designs. The authors believe that

  13. Net energy balance of tokamak fusion power plants

    International Nuclear Information System (INIS)

    Buende, R.

    1981-10-01

    The net energy balance for a tokamak fusion power plant was determined by using a PWR power plant as reference system, replacing the fission-specific components by fusion-specific components and adjusting the non-reactor-specific components to altered conditions. For determining the energy input to the fusion plant a method was developed that combines the advantages of the energetic input-output method with those of process chain analysis. A comparison with PWR, HTR, FBR, and coal-fired power plants is made. As a result the net energy balance of the fusion power plant turns out to be more advantageous than that of an LWR, HTR or coal-fired power plant and nearly in the same range as FBR power plants. (orig.)

  14. Net energy balance of tokamak fusion power plants

    International Nuclear Information System (INIS)

    Buende, R.

    1983-01-01

    The net energy balance for a tokamak fusion power plant of present day design is determined by using a PWR power plant as reference system, replacing the fission-specific components by fusion-specific components and adjusting the non-reactor-specific components to altered conditions. For determining the energy input to the fusion plant a method was developed that combines the advantages of the energetic input-output method with those of process chain analysis. A comparison with PWR, HTR, FBR, and coal-fired power plants is made. As a result the energy expenditures of the fusion power plant turn out to be lower than that of an LWR, HTR, or coal-fired power plant of equal net electric power output and nearly in the same range as FBR power plants. (orig.)

  15. Net energy balance of molasses based ethanol. The case of Nepal

    International Nuclear Information System (INIS)

    Khatiwada, Dilip; Silveira, Semida

    2009-01-01

    This paper evaluates life cycle energy analysis of molasses based ethanol (MOE) in Nepal. Net energy value (NEV), net renewable energy value (NREV) and energy yield ratio are used to evaluate the energy balance of MOE in Nepal. Total energy requirements in sugarcane farming, cane milling and ethanol conversion processes are estimated and energy allocation is made between co-products (molasses and sugar) as per their market prices. The result shows negative NEV (-13.05 MJ/L), positive NREV (18.36 MJ/L) and energy yield ratio (7.47). The higher positive value of NREV and energy yield ratio reveal that a low amount of fossil fuels are required to produce 1 L of MOE. However, negative NEV reveals that the total energy consumption (both fossil and renewables) to produce the ethanol is higher than its final energy content. Nevertheless, the renewable energy contribution amounts to 91.7% of total energy requirements. The effect of the increased price of molasses and reduced energy consumption in the sugarcane milling and ethanol conversion are found to be significant in determining the energy values and yield ratio of MOE. In addition, there are clear measures that can be taken to improve efficiency along the production chain. Finally, energy security, scarcity of hard currency for importing fossil fuels and opportunities for regional development are also strong reasons for considering local renewable energy options in developing countries. (author)

  16. Energy ratios in Finnish agricultural production

    Directory of Open Access Journals (Sweden)

    H. J. MIKKOLA

    2008-12-01

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

  17. Internet application: production-technical information system MoNET

    International Nuclear Information System (INIS)

    Tomiga, J.

    2004-01-01

    MoNET is the production-technical information system supporting engineering, operational and maintenance processes of distribution network administrator. It utilizes the model of distribution network that is situated in the geo-space relational database. The geo-space database represents an information base of operational-technical processes. It contains elements and equipment s of the distribution network, failures, operational events, maintenance records, but also, parcels, reference planimetry, e.g. and other subjects for which is relevant the positional datum - geo-space information. MoNET is typically exploited in the fields: - evidence of the subjects and equipment of network, technical documentation; - property administration; - planning of network development, support of designing and construction; - technical calculation; - breakdown controller centre; - maintenance management. MoNET can be implemented as the desktop application, however its first benefit is derived from its usage as the intranet application MoNET WEB for the whole enterprise or organisation. This version enables an unrestricted number of end-users to enter this system. The end-users don't need any special software to enter the data of MoNet WEB application, the pre-installed Internet Explorer will do. (author)

  18. 40 CFR 73.83 - Secretary of Energy's action on net income neutrality applications.

    Science.gov (United States)

    2010-07-01

    ... Renewable Energy Reserve § 73.83 Secretary of Energy's action on net income neutrality applications. (a) First come, first served. The Secretary of Energy will process and certify net income neutrality... of Energy determines that the net income neutrality certification application does not meet the...

  19. HANPP Collection: Human Appropriation of Net Primary Productivity (HANPP) by Country and Product

    Data.gov (United States)

    National Aeronautics and Space Administration — The Human Appropriation of Net Primary Productivity (HANPP) by Country and Product portion of the HANPP Collection contains tabular data on carbon-equivalents of...

  20. Final Technical Report - Autothermal Styrene Manufacturing Process with Net Export of Energy

    Energy Technology Data Exchange (ETDEWEB)

    Trubac, Robert , E.; Lin, Feng; Ghosh, Ruma: Greene, Marvin

    2011-11-29

    The overall objectives of the project were to: (a) develop an economically competitive processing technology for styrene monomer (SM) that would reduce process energy requirements by a minimum 25% relative to those of conventional technology while achieving a minimum 10% ROI; and (b) advance the technology towards commercial readiness. This technology is referred to as OMT (Oxymethylation of Toluene). The unique energy savings feature of the OMT technology would be replacement of the conventional benzene and ethylene feedstocks with toluene, methane in natural gas and air or oxygen, the latter of which have much lower specific energy of production values. As an oxidative technology, OMT is a net energy exporter rather than a net energy consumer like the conventional ethylbenzene/styrene (EB/SM) process. OMT plants would ultimately reduce the cost of styrene monomer which in turn will decrease the costs of polystyrene making it perhaps more cost competitive with competing polymers such as polypropylene.

  1. Net community production in the northern Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Sarma, V.V.S.S.

    . On the other hand, Sarma [2004, Net community production in the Bay of Bengal: Oxygen mass balance approach, submitted to Bio- geochemistry, 2008] computed NCP using a regional model of oxygen mass balance in the NIO. Bates et al. [2006] also estimated NCP... using an inorganic carbon mass balance model for the entire Indian Ocean. This chapter combines the results obtained from direct measurements and models and aims at improving our understanding of processes con­ trolling NCP in the NIO...

  2. Lessons Learned from Net Zero Energy Assessments and Renewable Energy Projects at Military Installations

    Energy Technology Data Exchange (ETDEWEB)

    Callahan, M.; Anderson, K.; Booth, S.; Katz, J.; Tetreault, T.

    2011-09-01

    Report highlights the increase in resources, project speed, and scale that is required to achieve the U.S. Department of Defense (DoD) energy efficiency and renewable energy goals and summarizes the net zero energy installation assessment (NZEI) process and the lessons learned from NZEI assessments and large-scale renewable energy projects implementations at DoD installations.

  3. Variations of Terrestrial Net Primary Productivity in East Asia

    Directory of Open Access Journals (Sweden)

    Fangmin Zhang

    2012-01-01

    Full Text Available Due to the heterogeneity and complexity of terrestrial ecosystems of East Asia, a better understanding of relationships between climate change and net primary productivity (NPP distribution is important to predict future carbon dynamics. The objective of this study is to analyze the temporal-spatial patterns of NPP in East Asia (10°S - 55°N, 60 - 155°E from 1982 to 2006 using the process-based Boreal Ecosystem Productivity Simulator (BEPS model. Prior to the regional simulation, the annual simulated NPP was validated using field observed NPP demonstrating the ability of BEPS to simulate NPP in different ecosystems of East Asia.

  4. Intelligent Controls for Net-Zero Energy Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Li, Haorong; Cho, Yong; Peng, Dongming

    2011-10-30

    The goal of this project is to develop and demonstrate enabling technologies that can empower homeowners to convert their homes into net-zero energy buildings in a cost-effective manner. The project objectives and expected outcomes are as follows: • To develop rapid and scalable building information collection and modeling technologies that can obtain and process “as-built” building information in an automated or semiautomated manner. • To identify low-cost measurements and develop low-cost virtual sensors that can monitor building operations in a plug-n-play and low-cost manner. • To integrate and demonstrate low-cost building information modeling (BIM) technologies. • To develop decision support tools which can empower building owners to perform energy auditing and retrofit analysis. • To develop and demonstrate low-cost automated diagnostics and optimal control technologies which can improve building energy efficiency in a continual manner.

  5. Global net primary production and heterotrophic respiration for 1987

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, R.E. Jr.; Piper, S.C.; Nemani, R. [Univ. of Montana, Missoula, MT (United States)]|[Scripps Institute of Oceanography, La Jolla, CA (United States)] [and others

    1995-06-01

    An ecosystem process model, BIOME-BGC, was parameterized and used to simulate the actual net primary production and heterotrophic respiration using daily climatic data, land cover type, leaf area index gridded to 1{degree} latitude by 1{degree} longitude grid cells for the year 1987. Global net primary production was 52 Pg C. These estimates were validated directly by two different methods. First, the grid cells were aggregated and used as inputs to a 3D atmospheric transport model, to compare CO{sub 2} station data with predictions. We simulated the intra-annual variation of atmospheric CO{sub 2} well for the northern hemisphere, but not for the southern hemisphere. Second, we calculated the net {sup 13}C uptake of vegetation, which is a function of water use efficiency. The {sup 13}C/{sup 12}C ratios agreed with measured data, indicating a strong limitation of global primary processes by the hydrologic cycle, especially precipitation. These are different from other global carbon models as we can simulate the year-to-year variation of climate, including El Nino, on the global carbon cycle.

  6. Human appropriation of net primary production in the United Kingdom, 1800-2000. Changes in society's impact on ecological energy flows during the agrarian-industrial transition

    Energy Technology Data Exchange (ETDEWEB)

    Musel, Annabella [Institute of Social Ecology, Alpen-Adria University Klagenfurt - Graz - Wien, Schottenfeldgasse 29, 1070 Vienna (Austria)

    2009-12-15

    This paper presents an empirical analysis of the United Kingdom's society's long-term intervention into the energy flows of domestic terrestrial ecosystems through the human appropriation of aboveground net primary production (aHANPP) covering the period 1800-2000. The depicted aHANPP trajectory and the historical development of its components are discussed in view of a continuously increasing population and the transition process from an agrarian to an industrial socioecological regime. During the 19th century, aHANPP shows a steady decline from its level of 71% in 1800. While even higher levels were reached during the mid 20th century, the trend during the last forty years of the period under investigation again shows a reduction of aHANPP, which lies at 68% in the year 2000. The high values of aHANPP in the United Kingdom are primarily attributable to the limited amount of forest in comparison to large agricultural areas. At the beginning of the studied period, the relative stabilisation or even decrease in aHANPP in comparison to population development was made possible through the area expansion of and productivity increases on cropland and permanent pastures. Later this was made possible through the outsourcing of biomass harvest, by satisfying local nutritional demands by means of overseas imports, and as from the mid 20th century through huge amounts of fossil fuel based inputs into agriculture (e.g. increased amounts of fertilizers and motorized traction) which allowed increases in biomass harvest to be decoupled from HANPP. (author)

  7. C-NET: the Centre for Nuclear Energy Technology

    International Nuclear Information System (INIS)

    Roberts, J.W.

    2011-01-01

    The Centre for Nuclear Energy Technology was established as part of the Dalton Nuclear Institute at The University of Manchester in 2009 to focus the UK research on front-end nuclear technologies. This includes plant-life extension, new build, naval propulsion and next generation reactors. Building on £4M of government funding through the North West Development Agency (NWDA), C-NET will act as a hub for nuclear research in the North West of England collaborating with both universities and industry. (author)

  8. Fiscal 1995 achievement report. International Clean Energy Network Using Hydrogen Conversion (WE-NET) technology

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    Research and development was performed for the WE-NET (World Energy Network) project which aims to carry out hydrogen production, transportation, and supply to consumers, by the use of renewable energy. Under subtask 1, besides investigation of a pilot plant of phase 2, the WE-NET image as a whole was studied. Under subtask 2, technical information was exchanged at an international symposium and a long-term vision of the international network was discussed. Under subtask 3, for the evaluation of the effect of hydrogen energy introduction on the global level, national level, and city level, simulation models were discussed and improved. Under subtask 4, tests and studies were made concerning electrode bonding methods. Under subtask 5, the Neon Brayton cycle process was surveyed and studied as a hydrogen liquefaction cycle. Under subtasks 6-9, furthermore, surveys and studies were made about techniques relating to low-temperature substances, hydrogen energy, hydrogen combustion turbines, and so forth. (NEDO)

  9. Implications of net energy-return-on-investment for a low-carbon energy transition

    Science.gov (United States)

    King, Lewis C.; van den Bergh, Jeroen C. J. M.

    2018-04-01

    Low-carbon energy transitions aim to stay within a carbon budget that limits potential climate change to 2 °C—or well below—through a substantial growth in renewable energy sources alongside improved energy efficiency and carbon capture and storage. Current scenarios tend to overlook their low net energy returns compared to the existing fossil fuel infrastructure. Correcting from gross to net energy, we show that a low-carbon transition would probably lead to a 24-31% decline in net energy per capita by 2050, which implies a strong reversal of the recent rising trends of 0.5% per annum. Unless vast end-use efficiency savings can be achieved in the coming decades, current lifestyles might be impaired. To maintain the present net energy returns, solar and wind renewable power sources should grow two to three times faster than in other proposals. We suggest a new indicator, `energy return on carbon', to assist in maximizing the net energy from the remaining carbon budget.

  10. Zero Net Energy Myths and Modes of Thought

    Energy Technology Data Exchange (ETDEWEB)

    Rajkovich, Nicholas B.; Diamond, Rick; Burke, Bill

    2010-09-20

    The U.S. Department of Energy (DOE), the California Public Utilities Commission (CPUC), and a number of professional organizations have established a target of zero net energy (ZNE) in buildings by 2030. One definition of ZNE is a building with greatly reduced needs for energy through efficiency gains with the balance of energy needs supplied by renewable technologies. The push to ZNE is a response to research indicating that atmospheric concentrations of greenhouse gases have increased sharply since the eighteenth century, resulting in a gradual warming of the Earth?s climate. A review of ZNE policies reveals that the organizations involved frame the ZNE issue in diverse ways, resulting in a wide variety of myths and a divergent set of epistemologies. With federal and state money poised to promote ZNE, it is timely to investigate how epistemologies, meaning a belief system by which we take facts and convert them into knowledge upon which to take action, and the propagation of myths might affect the outcome of a ZNE program. This paper outlines myths commonly discussed in the energy efficiency and renewable energy communities related to ZNE and describes how each myth is a different way of expressing"the truth." The paper continues by reviewing a number of epistemologies common to energy planning, and concludes that the organizations involved in ZNE should work together to create a"collaborative rationality" for ZNE. Through this collaborative framework it is argued that we may be able to achieve the ZNE and greenhouse gas mitigation targets.

  11. NET-ZERO ENERGY BUILDING OPERATOR TRAINING PROGRAM (NZEBOT)

    Energy Technology Data Exchange (ETDEWEB)

    Brizendine, Anthony; Byars, Nan; Sleiti, Ahmad; Gehrig, Bruce; Lu, Na

    2012-12-31

    The primary objective of the Net-Zero Energy Building Operator Training Program (NZEBOT) was to develop certificate level training programs for commercial building owners, managers and operators, principally in the areas of energy / sustainability management. The expected outcome of the project was a multi-faceted mechanism for developing the skill-based competency of building operators, owners, architects/engineers, construction professionals, tenants, brokers and other interested groups in energy efficient building technologies and best practices. The training program draws heavily on DOE supported and developed materials available in the existing literature, as well as existing, modified, and newly developed curricula from the Department of Engineering Technology & Construction Management (ETCM) at the University of North Carolina at Charlotte (UNC-Charlotte). The project goal is to develop a certificate level training curriculum for commercial energy and sustainability managers and building operators that: 1) Increases the skill-based competency of building professionals in energy efficient building technologies and best practices, and 2) Increases the workforce pool of expertise in energy management and conservation techniques. The curriculum developed in this project can subsequently be used to establish a sustainable energy training program that can contribute to the creation of new “green” job opportunities in North Carolina and throughout the Southeast region, and workforce training that leads to overall reductions in commercial building energy consumption. Three energy training / education programs were developed to achieve the stated goal, namely: 1. Building Energy/Sustainability Management (BESM) Certificate Program for Building Managers and Operators (40 hours); 2. Energy Efficient Building Technologies (EEBT) Certificate Program (16 hours); and 3. Energy Efficent Buildings (EEB) Seminar (4 hours). Training Program 1 incorporates the following

  12. Net-Zero Energy Home Grows Up: Lessons and Puzzles from 10 Years of Data; Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Sparn, Bethany; Earle, Lieko; Christensen, Craig; Norton, Paul

    2016-05-17

    In 2005, Habitat for Humanity of Metro Denver, with support from NREL and other partners, built one of the first homes in the US to achieve net-zero energy based on monitored data. A family of three moved into the house when it was completed and lives there still. The home has been monitored continuously for the past ten years. Although PV production has remained steady, net energy performance has varied each year. The home was a net producer of energy annually in each of the first three years and in the ninth year, but not in years four through eight. Over the years, the PV system provided between 124% and 64% of the home source energy use. Electricity use in the home increased steadily during the first eight years, even though no significant new appliance was introduced into the house, such as a window air conditioner. Miscellaneous electric loads and space heating, both strongly dependent on occupant behavior, appear to be primarily responsible for the observed increase in energy use. An interesting aspect of this case study is how, even within a single family, natural changes in occupant lifestyles over time (e.g., kids growing up, schedules changing) can substantially impact the overall energy intensity of a home. Data from the last ten years will be explored for lessons learned that can improve the way we design low-load homes without sacrificing comfort or convenience for the occupants, and how we can make realistic predictions of long-term energy performance.

  13. Net present value analysis of the economic production quantity

    OpenAIRE

    Disney, Stephen Michael; Warburton, R. D. H.; Zhong, Q. C.

    2013-01-01

    Using Laplace transforms we extend the economic production quantity (EPQ) model by analysing cash flows from a net present value (NPV) viewpoint. We obtain an exact expression for the present value of the cash flows in the EPQ problem. From this, we are able to derive the optimal batch size. We obtain insights into the monotonicity and convexity of the present value of each of the cash flows, and show that there is a unique minimum in the present value of the sum of the cash flows in the exte...

  14. A Cellular Approach to Net-Zero Energy Cities

    Directory of Open Access Journals (Sweden)

    Miguel Amado

    2017-11-01

    Full Text Available Recent growth in the use of photovoltaic technology and a rapid reduction in its cost confirms the potential of solar power on a large scale. In this context, planning for the deployment of smart grids is among the most important challenges to support the increased penetration of solar energy in urban areas and to ensure the resilience of the electricity system. As part this effort, the present paper describes a cellular approach to a Net-Zero energy concept, based on the balance between the potential solar energy supply and the existing consumption patterns at the urban unit scale. To do that, the Geographical Urban Units Delimitation model (GUUD has been developed and tested on a case study. By applying the GUUD model, which combines Geographic Information Systems (GIS, parametric modelling, and solar dynamic analysis, the whole area of the city was divided into urban cells, categorized as solar producers and energy consumers. The discussion around three theoretical scenarios permits us to explore how smart grids can be approached and promoted from an urban planning perspective. The paper provides insights into how urban planning can be a driver to optimize and manage energy balance across the city if the deployment of smart grids is correctly integrated in its operative process.

  15. Fiscal 1996 achievement report. International Clean Energy Network Using Hydrogen Conversion (WE-NET) technology

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    Research and development was performed for the WE-NET (World Energy Network) project which aims to carry out hydrogen production, transportation, and supply to consumers, by the use of renewable energy. Under subtask 1, the whole WE-NET project was subjected to evaluation, which included coordination between the respective tasks. Under subtask 2, information exchange and research cooperation were carried out with research institutes overseas. Under subtask 3, a conceptual design was prepared of a total system using ammonia as the medium for hydrogen transportation, accident data were collected and screened, and safety measures and evaluation techniques were developed and improved. Under subtask 4, the hot press method and the electroless plating method were selected as better electrode bonding methods. Under subtask 5, hydrogen liquefaction cycle processes, liquid hydrogen tankers, storage facilities, etc., were studied. Under subtasks 6-9, furthermore, investigations were conducted about low-temperature substance technology, hydrogen energy, hydrogen combustion turbine, etc. (NEDO)

  16. Ignition in net for different energy confinement time scalings

    International Nuclear Information System (INIS)

    Johner, J.; Prevot, F.

    1988-06-01

    A zero-dimensional profile dependent model is used to assess the feasibility of ignition in the extended version of NET. Five recent scalings for the energy confinement time (Goldston, Kaye All, Kaye Big, Shimomura-Odajima, Rebut-Lallia) are compared in the frame of two different scenarii, i.e., H-mode with a flat density profile or L-mode with a peaked density profile. For the flat density H-mode case, ignition is accessible with none of the scalings except Rebut-Lallia's. For the peaked density L-mode case, ignition is accessible with none of the scalings except Rebut-Lallia's. For the two Kaye's scalings, ignition is forbidden in H-mode even with the peaked density profile. For the Rebut-Lallia scaling, ignition is allowed in L-mode even with the flat density profile

  17. vNet Zero Energy for Radio Base Stations- Balearic Scenario

    DEFF Research Database (Denmark)

    Sabater, Pere; Mihovska, Albena Dimitrova; Pol, Andreu Moia

    2016-01-01

    The Balearic Islands have one of the best telecommunications infrastructures in Spain, with more than 1500 Radio Base Stations (RBS) covering a total surface of 4.991,66 km². This archipelago has high energy consumption, with high CO2 emissions, due to an electrical energy production system mainly...... based on coal and fossil fuels which is not an environmentally sustainable scenario. The aim of this study is to identify the processes that would reduce the energy consumption and greenhouse gas emissions, designing a target scenario featuring "zero CO2 emissions" and "100% renewable energies" in RBS....... The energy costs, CO2 emissions and data traffic data used for the study are generated by a sample of RBS from the Balearic Islands. The results are shown in terms of energy performance for a normal and net zero emissions scenarios....

  18. Fiscal 2000 report on the Phase II R and D of the international hydrogen utilization clean energy network system technology (WE-NET). Task 8. Development of hydrogen production technology; 2000 nendo suiso riyo kokusai clean energy system gijutsu (WE-NET) dai 2 ki kenkyu kaihatsu seika hokokusho. 8. Suiso seizo gijutsu no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    Research and development was carried out to establish a hydrogen production technology in the electrolysis of water using the solid macromolecular electrolyte method expected to be more efficient and less costly than the conventional hydrogen production methods. In the development of large area electrolysis cell lamination, a lamination comprising ten 2,500cm{sup 2} cells was fabricated, and a value exceeding the target energy efficiency of 90% was achieved. In the fabrication of stacks for hydrogen service stations, a lamination of ten cell stacks of 1,000cm{sup 2} was built, which achieved energy efficiency of not less than 90% at the an electrolysis temperature of 100 degrees C. A hydrogen production plant conceptual design was prepared under the conditions of hydrogen generation amount: 10,000Nm{sup 3}/h, electrode area: 10,000cm{sup 2}/cell, current density: 2.5A/cm{sup 2}, operating temperature: 120 degrees C, cell voltage: 1.705V, total number of cells: 976, stack constitution: 122/stack, and the number of stacks: 8. The result of studies placed the plant construction cost at 2.18-billion yen including building and civil engineering costs, and the hydrogen production unit cost at 28.4 yen/Nm{sup 3}. (NEDO)

  19. HANPP Collection: Global Patterns in Human Appropriation of Net Primary Productivity (HANPP)

    Data.gov (United States)

    National Aeronautics and Space Administration — The Global Patterns in Human Appropriation of Net Primary Productivity (HANPP) portion of the HANPP Collection represents a digital map of human appropriation of net...

  20. Higher moments of net kaon multiplicity distributions at RHIC energies for the search of QCD Critical Point at STAR

    Directory of Open Access Journals (Sweden)

    Sarkar Amal

    2013-11-01

    Full Text Available In this paper we report the measurements of the various moments mean (M, standard deviation (σ skewness (S and kurtosis (κ of the net-Kaon multiplicity distribution at midrapidity from Au+Au collisions at √sNN = 7.7 to 200 GeV in the STAR experiment at RHIC in an effort to locate the critical point in the QCD phase diagram. These moments and their products are related to the thermodynamic susceptibilities of conserved quantities such as net baryon number, net charge, and net strangeness as also to the correlation length of the system. A non-monotonic behavior of these variable indicate the presence of the critical point. In this work we also present the moments products Sσ, κσ2 of net-Kaon multiplicity distribution as a function of collision centrality and energies. The energy and the centrality dependence of higher moments of net-Kaons and their products have been compared with it0s Poisson expectation and with simulations from AMPT which does not include the critical point. From the measurement at all seven available beam energies, we find no evidence for a critical point in the QCD phase diagram for √sNN below 200 GeV.

  1. Wavestar Energy Production Outlook

    DEFF Research Database (Denmark)

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

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

  2. Fiscal 1999 hydrogen utilization international clean energy system technology (WE-NET). Phase 2 R and D (Task 8) - development of hydrogen production technology; 1999 nendo suiso riyo kokusai clean energy system gijutsu (WE-NET) dainiki kenkyu kaihatsu. Task 8. Suiso seizo gijutsu no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    R and D was conducted with the view of establishing hydrogen production technology based on the solid high polymer electrolyte water electrolysis method, which presumably offers higher efficiency and lower cost than conventional methods. This year, as well as implementing development of large-scale cell lamination (electrode area 2,500 cm{sup 2}, 10 cells) by using two hydrogen production methods (electroless plating method and hot press method), work was started for developing cells (electrode area 1,000 cm{sup 2}) for hydrogen stations. In the research on longterm durability improvement, with a 50 cm{sup 2} membrane electrolyte or cell, the evaluation test results were obtained of stable electrolytic performance showing more than 93% energy efficiency after 400 hour operation, under the conditions with electrolysis pressure 0.4MPa and electrolysis temperature 120 degree C. In a test of 1,000 cm{sup 2} prototype cell for hydrogen stations, the evaluation result was obtained for energy efficiency of 92% under the conditions with electrolysis pressure 0.5MPa and electrolysis temperature 120 degree C; thus, this year's target efficiency of over 90% was achieved. Further, enhancement of the quality was contrived for example by improving the electroless plating method and remodeling a roll press machine. (NEDO)

  3. Optimal balance between energy demand and onsite energy generation for robust net zero energy buildings considering future scenarios

    NARCIS (Netherlands)

    Kotireddy, R.R.; Hoes, P.; Hensen, J.L.M.

    2015-01-01

    Net-zero energy buildings have usually very low energy demand, and consequently heating ventilation and air conditioning (HVAC) systems are designed and controlled to meet this low energy demand. However, a number of uncertainties in the building use, operation and external conditions such as

  4. Estimating Net Primary Productivity Using Satellite and Ancillary Data

    Science.gov (United States)

    Choudhury, Bhaskar J.

    2002-01-01

    The net primary productivity (C) or the annual rate of carbon accumulation per unit ground area by terrestrial plant communities is the difference of gross photosynthesis (A(sub g)) and respiration (R) per unit ground area. Available field observations show that R is a large and variable fraction of A(sub g), although it is generally recognized that there are considerable difficulties in determining these fluxes, and thus pose challenge in assessing the accuracy. Further uncertainties arise in extrapolating field measurements (which are acquired over a hectare or so area) to regional scale. Here, an approach is presented for determining these fluxes using satellite and ancillary data to be representative of regional scale and allow assessment of interannual variation. A, has been expressed as the product of radiation use efficiency for gross photosynthesis by an unstressed canopy and intercepted photosynthetically active radiation, which is then adjusted for stresses due to soil water shortage and temperature away from optimum. R has been calculated as the sum of growth and maintenance components (respectively, R(sub g) and R(sub m)).The R(sub m) has been determined from nitrogen content of plant tissue per unit ground area, while R(sub g) has been obtained as a fraction of the difference of A(sub g) and R(sub m). Results for five consecutive years (1986-1990) are presented for the Amazon-Tocontins, Mississippi, and Ob River basins.

  5. Predicting plankton net community production in the Atlantic Ocean

    Science.gov (United States)

    Serret, Pablo; Robinson, Carol; Fernández, Emilio; Teira, Eva; Tilstone, Gavin; Pérez, Valesca

    2009-07-01

    We present, test and implement two contrasting models to predict euphotic zone net community production (NCP), which are based on 14C primary production (PO 14CP) to NCP relationships over two latitudinal (ca. 30°S-45°N) transects traversing highly productive and oligotrophic provinces of the Atlantic Ocean (NADR, CNRY, BENG, NAST-E, ETRA and SATL, Longhurst et al., 1995 [An estimation of global primary production in the ocean from satellite radiometer data. Journal of Plankton Research 17, 1245-1271]). The two models include similar ranges of PO 14CP and community structure, but differ in the relative influence of allochthonous organic matter in the oligotrophic provinces. Both models were used to predict NCP from PO 14CP measurements obtained during 11 local and three seasonal studies in the Atlantic, Pacific and Indian Oceans, and from satellite-derived estimates of PO 14CP. Comparison of these NCP predictions with concurrent in situ measurements and geochemical estimates of NCP showed that geographic and annual patterns of NCP can only be predicted when the relative trophic importance of local vs. distant processes is similar in both modeled and predicted ecosystems. The system-dependent ability of our models to predict NCP seasonality suggests that trophic-level dynamics are stronger than differences in hydrodynamic regime, taxonomic composition and phytoplankton growth. The regional differences in the predictive power of both models confirm the existence of biogeographic differences in the scale of trophic dynamics, which impede the use of a single generalized equation to estimate global marine plankton NCP. This paper shows the potential of a systematic empirical approach to predict plankton NCP from local and satellite-derived P estimates.

  6. Targeting Net Zero Energy at Marine Corps Base Kaneohe Bay, Hawaii: Assessment and Recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Burman, K.; Kandt, A.; Lisell, L.; Booth, S.; Walker, A.; Roberts, J.; Falcey, J.

    2011-11-01

    DOD's U.S. Pacific Command has partnered with the U.S. Department of Energy's (DOE) National Renewable Energy Laboratory (NREL) to assess opportunities for increasing energy security through renewable energy and energy efficiency in Hawaii installations. NREL selected Marine Corps Base Hawaii (MCBH), Kaneohe Bay to receive technical support for net zero energy assessment and planning funded through the Hawaii Clean Energy Initiative (HCEI). NREL performed a comprehensive assessment to appraise the potential of MCBH Kaneohe Bay to achieve net zero energy status through energy efficiency, renewable energy, and electric vehicle integration. This report summarizes the results of the assessment and provides energy recommendations.

  7. Chapter 21: Estimating Net Savings - Common Practices. The Uniform Methods Project: Methods for Determining Energy Efficiency Savings for Specific Measures

    Energy Technology Data Exchange (ETDEWEB)

    Kurnik, Charles W [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Violette, Daniel M. [Navigant, Boulder, CO (United States); Rathbun, Pamela [Tetra Tech, Madison, WI (United States)

    2017-11-02

    This chapter focuses on the methods used to estimate net energy savings in evaluation, measurement, and verification (EM and V) studies for energy efficiency (EE) programs. The chapter provides a definition of net savings, which remains an unsettled topic both within the EE evaluation community and across the broader public policy evaluation community, particularly in the context of attribution of savings to a program. The chapter differs from the measure-specific Uniform Methods Project (UMP) chapters in both its approach and work product. Unlike other UMP resources that provide recommended protocols for determining gross energy savings, this chapter describes and compares the current industry practices for determining net energy savings but does not prescribe methods.

  8. Responses in live weight change to net energy intake in dairy cows

    DEFF Research Database (Denmark)

    Jensen, Charlotte; Østergaard, Søren; Bertilsson, Jan

    2015-01-01

    The objective of this analysis was to estimate the effect of increased energy intake on daily live weight changes during the first 100 days of lactation of primiparous and multiparous cows. A data set with 78 observations (treatment means) was compiled from 6 production trials from Denmark, Norway...... or multiparous. Feed ration energy values were recalculated by use of NorFor to obtain consistent energy expression in all trials as opposed to the varying feed evaluation systems used in original analysis of trials. Regression analysis with linear and quadratic effects were performed on live weight...... change were made by linear mixed effects model with trial as random factor. For both primiparous and multiparous cows there was an increasing curvilinear response at a decreasing rate to increased net energy intake and the daily live weight change at day 30 was negative and at day 90 it was positive...

  9. Scaling net ecosystem production and net biome production over a heterogeneous region in the western United States

    Directory of Open Access Journals (Sweden)

    D. P. Turner

    2007-08-01

    Full Text Available Bottom-up scaling of net ecosystem production (NEP and net biome production (NBP was used to generate a carbon budget for a large heterogeneous region (the state of Oregon, 2.5×105 km2 in the western United States. Landsat resolution (30 m remote sensing provided the basis for mapping land cover and disturbance history, thus allowing us to account for all major fire and logging events over the last 30 years. For NEP, a 23-year record (1980–2002 of distributed meteorology (1 km resolution at the daily time step was used to drive a process-based carbon cycle model (Biome-BGC. For NBP, fire emissions were computed from remote sensing based estimates of area burned and our mapped biomass estimates. Our estimates for the contribution of logging and crop harvest removals to NBP were from the model simulations and were checked against public records of forest and crop harvesting. The predominately forested ecoregions within our study region had the highest NEP sinks, with ecoregion averages up to 197 gC m−2 yr−1. Agricultural ecoregions were also NEP sinks, reflecting the imbalance of NPP and decomposition of crop residues. For the period 1996–2000, mean NEP for the study area was 17.0 TgC yr−1, with strong interannual variation (SD of 10.6. The sum of forest harvest removals, crop removals, and direct fire emissions amounted to 63% of NEP, leaving a mean NBP of 6.1 TgC yr−1. Carbon sequestration was predominantly on public forestland, where the harvest rate has fallen dramatically in the recent years. Comparison of simulation results with estimates of carbon stocks, and changes in carbon stocks, based on forest inventory data showed generally good agreement. The carbon sequestered as NBP, plus accumulation of forest products in slow turnover pools, offset 51% of the annual emissions of fossil fuel CO2 for the state. State-level NBP dropped below zero in 2002

  10. Productivity and energy efficiency

    Energy Technology Data Exchange (ETDEWEB)

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

    1995-12-31

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

  11. 19 CFR 151.47 - Optional entry of net quantity of petroleum or petroleum products.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 2 2010-04-01 2010-04-01 false Optional entry of net quantity of petroleum or petroleum products. 151.47 Section 151.47 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF... Petroleum and Petroleum Products § 151.47 Optional entry of net quantity of petroleum or petroleum products...

  12. Spatial scaling of net primary productivity using subpixel landcover information

    Science.gov (United States)

    Chen, X. F.; Chen, Jing M.; Ju, Wei M.; Ren, L. L.

    2008-10-01

    Gridding the land surface into coarse homogeneous pixels may cause important biases on ecosystem model estimations of carbon budget components at local, regional and global scales. These biases result from overlooking subpixel variability of land surface characteristics. Vegetation heterogeneity is an important factor introducing biases in regional ecological modeling, especially when the modeling is made on large grids. This study suggests a simple algorithm that uses subpixel information on the spatial variability of land cover type to correct net primary productivity (NPP) estimates, made at coarse spatial resolutions where the land surface is considered as homogeneous within each pixel. The algorithm operates in such a way that NPP obtained from calculations made at coarse spatial resolutions are multiplied by simple functions that attempt to reproduce the effects of subpixel variability of land cover type on NPP. Its application to a carbon-hydrology coupled model(BEPS-TerrainLab model) estimates made at a 1-km resolution over a watershed (named Baohe River Basin) located in the southwestern part of Qinling Mountains, Shaanxi Province, China, improved estimates of average NPP as well as its spatial variability.

  13. The CAFE model: A net production model for global ocean phytoplankton

    Science.gov (United States)

    Silsbe, Greg M.; Behrenfeld, Michael J.; Halsey, Kimberly H.; Milligan, Allen J.; Westberry, Toby K.

    2016-12-01

    The Carbon, Absorption, and Fluorescence Euphotic-resolving (CAFE) net primary production model is an adaptable framework for advancing global ocean productivity assessments by exploiting state-of-the-art satellite ocean color analyses and addressing key physiological and ecological attributes of phytoplankton. Here we present the first implementation of the CAFE model that incorporates inherent optical properties derived from ocean color measurements into a mechanistic and accurate model of phytoplankton growth rates (μ) and net phytoplankton production (NPP). The CAFE model calculates NPP as the product of energy absorption (QPAR), and the efficiency (ϕμ) by which absorbed energy is converted into carbon biomass (CPhyto), while μ is calculated as NPP normalized to CPhyto. The CAFE model performance is evaluated alongside 21 other NPP models against a spatially robust and globally representative set of direct NPP measurements. This analysis demonstrates that the CAFE model explains the greatest amount of variance and has the lowest model bias relative to other NPP models analyzed with this data set. Global oceanic NPP from the CAFE model (52 Pg C m-2 yr-1) and mean division rates (0.34 day-1) are derived from climatological satellite data (2002-2014). This manuscript discusses and validates individual CAFE model parameters (e.g., QPAR and ϕμ), provides detailed sensitivity analyses, and compares the CAFE model results and parameterization to other widely cited models.

  14. Assessment of a novel alder biorefinery concept to meet demands of economics feasibility, energy production and long term environmental sustainability

    DEFF Research Database (Denmark)

    Thomsen, Tobias; Ahrenfeldt, Jesper; Thomsen, Sune Tjalfe

    2012-01-01

    system Energy Return on energy Invested 4.4, total system Exergy Return on exergy Invested 3.5, Net Energy Output 78 GJ/ha/year, Net Exergy Output 50 GJ/ha/year, Net carbon sequestration 0.8 ton CO2-eq/ha/year, Total product value 2030 euro/ha/year and Net Dry Matter Removal 90%....

  15. Energy production systems engineering

    CERN Document Server

    Blair, Thomas Howard

    2017-01-01

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

  16. Prediction of net energy consumption based on economic indicators (GNP and GDP) in Turkey

    International Nuclear Information System (INIS)

    Soezen, Adnan; Arcaklioglu, Erol

    2007-01-01

    The most important theme in this study is to obtain equations based on economic indicators (gross national product-GNP and gross domestic product-GDP) and population increase to predict the net energy consumption of Turkey using artificial neural networks (ANNs) in order to determine future level of the energy consumption and make correct investments in Turkey. In this study, three different models were used in order to train the ANN. In one of them (Model 1), energy indicators such as installed capacity, generation, energy import and energy export, in second (Model 2), GNP was used and in the third (Model 3), GDP was used as the input layer of the network. The net energy consumption (NEC) is in the output layer for all models. In order to train the neural network, economic and energy data for last 37 years (1968-2005) are used in network for all models. The aim of used different models is to demonstrate the effect of economic indicators on the estimation of NEC. The maximum mean absolute percentage error (MAPE) was found to be 2.322732, 1.110525 and 1.122048 for Models 1, 2 and 3, respectively. R 2 values were obtained as 0.999444, 0.999903 and 0.999903 for training data of Models 1, 2 and 3, respectively. The ANN approach shows greater accuracy for evaluating NEC based on economic indicators. Based on the outputs of the study, the ANN model can be used to estimate the NEC from the country's population and economic indicators with high confidence for planing future projections

  17. Energy balance of the lavender oil production

    Directory of Open Access Journals (Sweden)

    Osman GÖKDOĞAN

    2016-06-01

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

  18. Modelling of phase change materials in the Toronto SUI net zero energy house using TRNSYS

    Energy Technology Data Exchange (ETDEWEB)

    Siddiqui, O.; Fung, A.; Zhang, D. [Ryerson Polytechnic Univ., Toronto, ON (Canada). Dept. of Mechanical and Industrial Engineering

    2008-08-15

    In the context of building applications, phase change materials (PCM), can be defined as any heat storage material that can absorb a large amount of thermal energy while undergoing a change in phase, such as from a solid to a liquid phase. The incorporation of PCM into the building envelope can enhance occupant comfort through the reduction of indoor temperature fluctuations. It has also been shown to cause a decrease in the overall energy consumption associated with the heating and cooling of buildings. This paper extended the analysis of the impact of using PCM, which has traditionally focused on homes of ordinary construction, to incorporate low to zero energy homes using a model of the Toronto net zero energy house developed in TRNSYS. The paper provided a description of the TRNSYS model/methodology, with reference to the wall layer used in the net zero energy house, and model of the layout of the net zero energy house in TRYNSYS. The TRYNSYS/type 204 PCM component was also presented along with the simulation results in terms of the temperature profile of the third floor of the net zero energy house on a typical winter day with varying PCM concentrations; the temperature profile of the third floor of the net zero energy house on a typical summer day with varying PCM concentrations; yearly heating/cooling load requirements of the net zero energy house for a variety of thermal mass used; temperature profile of the third floor of the net zero energy house on a typical summer day when PCM and concrete slab was used; yearly temperature profile of the third floor of the net zero energy house, illustrating the impact of using PCM; and the yearly heating/cooling load of the net zero energy house as the concentration of PCM was varied. It was concluded that the use of building integrated PCM can reduce temperature fluctuations considerably in the summer but only slightly in the winter. 16 refs., 1 tab., 8 figs.

  19. ENERGY-NET (Energy, Environment and Society Learning Network): Best Practices to Enhance Informal Geoscience Learning

    Science.gov (United States)

    Rossi, R.; Elliott, E. M.; Bain, D.; Crowley, K. J.; Steiner, M. A.; Divers, M. T.; Hopkins, K. G.; Giarratani, L.; Gilmore, M. E.

    2014-12-01

    While energy links all living and non-living systems, the integration of energy, the environment, and society is often not clearly represented in 9 - 12 classrooms and informal learning venues. However, objective public learning that integrates these components is essential for improving public environmental literacy. ENERGY-NET (Energy, Environment and Society Learning Network) is a National Science Foundation funded initiative that uses an Earth Systems Science framework to guide experimental learning for high school students and to improve public learning opportunities regarding the energy-environment-society nexus in a Museum setting. One of the primary objectives of the ENERGY-NET project is to develop a rich set of experimental learning activities that are presented as exhibits at the Carnegie Museum of Natural History in Pittsburgh, Pennsylvania (USA). Here we detail the evolution of the ENERGY-NET exhibit building process and the subsequent evolution of exhibit content over the past three years. While preliminary plans included the development of five "exploration stations" (i.e., traveling activity carts) per calendar year, the opportunity arose to create a single, larger topical exhibit per semester, which was assumed to have a greater impact on museum visitors. Evaluative assessments conducted to date reveal important practices to be incorporated into ongoing exhibit development: 1) Undergraduate mentors and teen exhibit developers should receive additional content training to allow richer exhibit materials. 2) The development process should be distributed over as long a time period as possible and emphasize iteration. This project can serve as a model for other collaborations between geoscience departments and museums. In particular, these practices may streamline development of public presentations and increase the effectiveness of experimental learning activities.

  20. Net Zero Energy Military Installations: A Guide to Assessment and Planning

    Energy Technology Data Exchange (ETDEWEB)

    Booth, S.; Barnett, J.; Burman, K.; Hambrick, J.; Westby, R.

    2010-08-01

    The U.S. Department of Defense (DoD) recognizes the strategic importance of energy to its mission, and is working to reduce energy consumption and enhance energy self-sufficiency by drawing on local clean energy sources. A joint initiative formed between DoD and the U.S. Department of Energy (DOE) in 2008 to address military energy use led to a task force to examine the potential for net zero energy military installations, which would produce as much energy on site as they consume in buildings, facilities, and fleet vehicles. This report presents an assessment and planning process to examine military installations for net zero energy potential. Net Zero Energy Installation Assessment (NZEIA) presents a systematic framework to analyze energy projects at installations while balancing other site priorities such as mission, cost, and security.

  1. Estimating the net electricity energy generation and demand using the ant colony optimization approach. Case of Turkey

    International Nuclear Information System (INIS)

    Toksari, M. Duran

    2009-01-01

    This paper presents Turkey's net electricity energy generation and demand based on economic indicators. Forecasting model for electricity energy generation and demand is first proposed by the ant colony optimization (ACO) approach. It is multi-agent system in which the behavior of each ant is inspired by the foraging behavior of real ants to solve optimization problem. Ant colony optimization electricity energy estimation (ACOEEE) model is developed using population, gross domestic product (GDP), import and export. All equations proposed here are linear electricity energy generation and demand (linear A COEEGE and linear ACOEEDE) and quadratic energy generation and demand (quadratic A COEEGE and quadratic ACOEEDE). Quadratic models for both generation and demand provided better fit solution due to the fluctuations of the economic indicators. The ACOEEGE and ACOEEDE models indicate Turkey's net electricity energy generation and demand until 2025 according to three scenarios. (author)

  2. Utilization of net energy analysis as a method of evaluating energy systems

    International Nuclear Information System (INIS)

    Lee, Gi Won; Cho, Joo Hyun; Hah, Yung Joon

    1994-01-01

    It can be said that the upturn of Korean nuclear power program started in early 70's while future plants for the construction of new nuclear power plants virtually came to a halt in United States since the late 70's. It is projected that power plant systems from combination of nuclear and coal fired types might shift to all coal fired type in U.S., considering the current U.S. trend of construction on the new plants. However, with the depletion of natural resources, it may be desirable to understand the utilization of two competitive utility technologies in terms of invested energy. Presented in this paper is a method of comparing two energy systems in terms of energy investment and a brief result from energy economic analysis of nuclear power plant and coal fired steam power plant to illustrate the methodology. The method of comparison is Net Energy Analysis (NEA). In doing so, Input-Output Analysis (lOA) among industries and commodities is done. Using these information, net energy ratios are calculated and compared. Although NEA does not offer conclusive solution, it can be used as a screening process in decision making

  3. Material and energy productivity.

    Science.gov (United States)

    Steinberger, Julia K; Krausmann, Fridolin

    2011-02-15

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

  4. Energy Use Consequences of Ventilating a Net-Zero Energy House

    Science.gov (United States)

    Ng, Lisa C.; Payne, W. Vance

    2016-01-01

    A Net-Zero Energy Residential Test Facility (NZERTF) has been constructed at the National Institute of Standards and Technology (NIST) in Gaithersburg, Maryland to demonstrate that a home similar in size, aesthetics, and amenities to those in the surrounding communities can achieve net-zero energy use over the course of a year while meeting the average electricity and water use needs of a family of four in the United States. The facility incorporates renewable energy and energy efficient technologies, including an air-to-air heat pump system, a solar photovoltaic system, a solar thermal domestic hot water system, and a heat recovery ventilation system sized to meet American Society of Heating, Refrigeration, and Air-Conditioning Engineers (ASHRAE) Standard 62.2-2010 ventilation requirements. The largest energy end use within the home was space conditioning, which included heat loss through the building envelope, ventilation air supplied by the heat recovery ventilator (HRV), and internal loads. While HRVs are often described as being able to save energy when compared to ventilating without heat recovery, there have been no studies using a full year of measured data that determine the thermal load and energy impacts of HRV-based ventilation on the central heating and cooling system. Over the course of a year, continuous operation of the HRV at the NZERTF resulted in an annual savings of 7 % in heat pump energy use compared with the hypothetical case of ventilating without heat recovery. The heat pump electrical use varied from an increase of 5 % in the cooling months to 36 % savings in the heating months compared with ventilation without heat recovery. The increase in the cooling months occurred when the outdoor temperature was lower than the indoor temperature, during which the availability of an economizer mode would have been beneficial. Nevertheless, the fan energy required to operate the selected HRV at the NZERTF paid for itself in the heat pump energy saved

  5. Energy Use Consequences of Ventilating a Net-Zero Energy House.

    Science.gov (United States)

    Ng, Lisa C; Payne, W Vance

    2016-03-05

    A Net-Zero Energy Residential Test Facility (NZERTF) has been constructed at the National Institute of Standards and Technology (NIST) in Gaithersburg, Maryland to demonstrate that a home similar in size, aesthetics, and amenities to those in the surrounding communities can achieve net-zero energy use over the course of a year while meeting the average electricity and water use needs of a family of four in the United States. The facility incorporates renewable energy and energy efficient technologies, including an air-to-air heat pump system, a solar photovoltaic system, a solar thermal domestic hot water system, and a heat recovery ventilation system sized to meet American Society of Heating, Refrigeration, and Air-Conditioning Engineers (ASHRAE) Standard 62.2-2010 ventilation requirements. The largest energy end use within the home was space conditioning, which included heat loss through the building envelope, ventilation air supplied by the heat recovery ventilator (HRV), and internal loads. While HRVs are often described as being able to save energy when compared to ventilating without heat recovery, there have been no studies using a full year of measured data that determine the thermal load and energy impacts of HRV-based ventilation on the central heating and cooling system. Over the course of a year, continuous operation of the HRV at the NZERTF resulted in an annual savings of 7 % in heat pump energy use compared with the hypothetical case of ventilating without heat recovery. The heat pump electrical use varied from an increase of 5 % in the cooling months to 36 % savings in the heating months compared with ventilation without heat recovery. The increase in the cooling months occurred when the outdoor temperature was lower than the indoor temperature, during which the availability of an economizer mode would have been beneficial. Nevertheless, the fan energy required to operate the selected HRV at the NZERTF paid for itself in the heat pump energy saved

  6. LEAP Phase II, Net Energy Gain From Laser Fields in Vacuum

    International Nuclear Information System (INIS)

    Barnes, C.D.; Colby, E.R.; Plettner, T.

    2005-01-01

    The current Laser Electron Acceleration Program (LEAP) seeks to modulate the energy of an electron bunch by interaction of the electrons with a copropagating pair of crossed laser beams at 800 nm. We present an optical injector design for a LEAP cell so that it can be used to give net energy gain to an electron bunch. Unique features of the design are discussed which will allow this net energy gain and which will also provide a robust signature for the LEAP interaction

  7. LEAP Phase II, net energy gain from laser fields in vacuum

    International Nuclear Information System (INIS)

    Barnes, Christopher D.; Colby, Eric R.; Plettner, Tomas

    2002-01-01

    The current Laser Electron Acceleration Program (LEAP) seeks to modulate the energy of an electron bunch by interaction of the electrons with a copropagating pair of crossed laser beams at 800 nm. We present an optical injector design for a LEAP cell so that it can be used to give net energy gain to an electron bunch. Unique features of the design are discussed which will allow this net energy gain and which will also provide a robust signature for the LEAP interaction

  8. Risk of energy production

    International Nuclear Information System (INIS)

    Inhaber, Herbert.

    1978-03-01

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

  9. Federal Campuses Handbook for Net Zero Energy, Water, and Waste

    Energy Technology Data Exchange (ETDEWEB)

    None

    2017-08-14

    In 2015, the U.S. Department of Energy’s Office Energy Efficiency and Renewable Energy (EERE) defined a zero energy campus as "an energy-efficient campus where, on a source energy basis, the actual annual delivered energy is less than or equal to the on-site renewable exported energy." This handbook is focused on applying the EERE definition of zero energy campuses to federal sector campuses. However, it is not intended to replace, substitute, or modify any statutory or regulatory requirements and mandates.

  10. Energy production from biomass

    International Nuclear Information System (INIS)

    Bestebroer, S.I.

    1995-01-01

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

  11. Fire intensity impacts on post-fire temperate coniferous forest net primary productivity

    Science.gov (United States)

    Sparks, Aaron M.; Kolden, Crystal A.; Smith, Alistair M. S.; Boschetti, Luigi; Johnson, Daniel M.; Cochrane, Mark A.

    2018-02-01

    Fire is a dynamic ecological process in forests and impacts the carbon (C) cycle through direct combustion emissions, tree mortality, and by impairing the ability of surviving trees to sequester carbon. While studies on young trees have demonstrated that fire intensity is a determinant of post-fire net primary productivity, wildland fires on landscape to regional scales have largely been assumed to either cause tree mortality, or conversely, cause no physiological impact, ignoring the impacted but surviving trees. Our objective was to understand how fire intensity affects post-fire net primary productivity in conifer-dominated forested ecosystems on the spatial scale of large wildland fires. We examined the relationships between fire radiative power (FRP), its temporal integral (fire radiative energy - FRE), and net primary productivity (NPP) using 16 years of data from the MOderate Resolution Imaging Spectrometer (MODIS) for 15 large fires in western United States coniferous forests. The greatest NPP post-fire loss occurred 1 year post-fire and ranged from -67 to -312 g C m-2 yr-1 (-13 to -54 %) across all fires. Forests dominated by fire-resistant species (species that typically survive low-intensity fires) experienced the lowest relative NPP reductions compared to forests with less resistant species. Post-fire NPP in forests that were dominated by fire-susceptible species were not as sensitive to FRP or FRE, indicating that NPP in these forests may be reduced to similar levels regardless of fire intensity. Conversely, post-fire NPP in forests dominated by fire-resistant and mixed species decreased with increasing FRP or FRE. In some cases, this dose-response relationship persisted for more than a decade post-fire, highlighting a legacy effect of fire intensity on post-fire C dynamics in these forests.

  12. FY 2000 Project of international clean energy network using hydrogen conversion (WE-NET)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    Described herein are the FY 2000 results of the research and development project aimed at construction of the international clean energy network using hydrogen conversion (WE-NET). The projects include 12 tasks; system evaluation for, e.g., optimum scenario for introduction of hydrogen energy; experiments for hydrogen safety; study on the international cooperation for WE-NET; development of power generation technology using a 100kW cogeneration system including hydrogen-firing diesel engine; developmental research on vehicles driven by a hydrogen fuel cell system; developmental research on the basic technologies for PEFC utilizing pure hydrogen; developmental research on a 30Nm{sup 3}/hour hydrogen refueling station for vehicles; developmental research on hydrogen production technology; developmental research on hydrogen transportation and storage technology, e.g., liquid hydrogen pump; research and development of the databases of and processing technology for cryogenic materials exposed to liquid hydrogen; developmental research on hydrogen absorbing alloys for small-scale hydrogen transportation and storage systems; and study on innovative and leading technologies. (NEDO)

  13. Economic Investigation of Community-Scale Versus Building Scale Net-Zero Energy

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, Nicholas; Katipamula, Srinivas; Brambley, Michael R.; Reddy, T. A.

    2009-12-31

    The study presented in this report examines issues concerning whether achieving net-zero energy performance at the community scale provides economic and potentially overall efficiency advantages over strategies focused on individual buildings.

  14. Novel gelforming process for near net shape ceramic component production

    International Nuclear Information System (INIS)

    Franks, G.V.; Johnson, S.B.; Dunstan, D.E.

    2000-01-01

    A novel gelforming process for producing near-net shape ceramic components has been developed. A low viscosity, high volume fraction, ceramic suspension containing a small amount of bio-polymer is poured or injected into a mould. The suspension is gelled within the mould by a temperature activated crosslinking mechanism. The rheological behaviour of the body within the mould is changed from liquid-like to solid-like in a short period of time. The wet mechanical strength of the gelled bodies is sufficient to allow the body to be demoulded and handled without damaging the component. Near net shapes of complex geometry are formed in this way. The wet green body is then dried and densified using traditional methods. Potentially this process can be used to produce inexpensive reliable high strength ceramic components quickly and safely. Copyright (2000) The Australian Ceramic Society

  15. Optimum Temperatures for Net Primary Productivity of Three Tropical Seagrass Species

    OpenAIRE

    Collier, Catherine J.; Ow, Yan X.; Langlois, Lucas; Uthicke, Sven; Johansson, Charlotte L.; O'Brien, Katherine R.; Hrebien, Victoria; Adams, Matthew P.

    2017-01-01

    Rising sea water temperature will play a significant role in responses of the world's seagrass meadows to climate change. In this study, we investigated seasonal and latitudinal variation (spanning more than 1,500 km) in seagrass productivity, and the optimum temperatures at which maximum photosynthesis and net productivity (for the leaf and the whole plant) occurs, for three seagrass species (Cymodocea serrulata, Halodule uninervis, and Zostera muelleri). To obtain whole plant net production...

  16. Spreading The Net: The Multiple Benefits Of Energy Efficiency Improvements

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-07-01

    Improving energy efficiency can deliver a range of benefits to the economy and society. However energy efficiency programmes are often evaluated only on the basis of the energy savings they deliver. As a result, the full value of energy efficiency improvements in both national and global economies may be significantly underestimated. This also means that energy efficiency policy may not be optimised to target the potential of the full range of outcomes possible. Moreover, when the merit of energy efficiency programmes is judged solely on reductions in energy demand, programmes are susceptible to criticisms related to the rebound effect when the energy savings are less than expected due to other welfare gains. There are several reasons why the full range of outcomes from energy efficiency policy is not generally evaluated. First, it is due to the non-market, somewhat intangible, nature of the socioeconomic benefits, which makes them difficult to quantify. Second, the effects due to energy efficiency alone can be complex to isolate and to determine causality. Third, evaluators and policy makers working in the energy efficiency sphere are usually energy professionals, working for an energy agency or ministry, with little experience of how energy efficiency might impact other non-energy sectors. The result is an under-appreciation – and related underinvestment – in energy efficiency, and as a consequence, missed opportunities and benefits. These foregone benefits represent the ‘opportunity cost’ of failing to adequately evaluate and prioritize energy efficiency investments. The objective of this report is to fully outline the array of different benefits from improved energy efficiency and investigate their implications for policy design. By better understanding the different benefits arising from energy efficiency it should be easier for policy makers to prioritise the most significant outcomes, in addition to energy savings, in optimising energy efficiency

  17. Baseline measures for net-proton distributions in high energy heavy-ion collisions

    International Nuclear Information System (INIS)

    Netrakanti, P.K.; Mishra, D.K.; Mohanty, A.K.; Mohanty, B.

    2014-01-01

    The STAR experiment at the Relativistic Heavy-Ion Collider facility has reported results for the cumulants and their ratios from the net-proton distributions upto the fourth order cumulants at various collision energies. These measurements were carried to look for the signatures of the possible critical point (CP) in the phase diagram for a system undertaking strong interactions. The results show an intriguing dependence of the cumulant ratios C 3 /C 2 and C 4 /C 2 as a function of beam energy. The beam energy dependence appears to be non-monotonic in nature. However the experiment also reports that the energy dependence is observed to be consistent with expectation from an approach based on the independent production of proton and anti-protons in the collisions. In this paper we emphasize the need to have a proper baseline for appropriate interpretation of the cumulant measurements and argue that the comparison to independent production approach needs to be done with extreme caution

  18. Gestió d'un catàleg de productes amb Microsoft .NET

    OpenAIRE

    Otero Dopico, Àngels

    2007-01-01

    El projecte és una aplicació de gestió d'un catàleg de productes realitzada amb la tecnologia .NET. En concret he fet servir l'entorn de programació Microsoft Visual Studio 2005 i el llenguatge Visual Basic .NET com elements principals. El proyecto es una aplicación de gestión de un catálogo de productos realizada con la tecnología .NET. En concreto se ha usado el entorno de programación Microsoft Visual Studio 2005 y el lenguaje Visual Basic .NET como elementos principales. This projec...

  19. COST OF PRODUCTION, GROSS RETURN AND NET PROFIT IN COMMERCIAL EGG PRODUCTION

    Directory of Open Access Journals (Sweden)

    M. Farooq, Zahoor-ul-Haq1, M.A. Mian, F.R. Durrani and M. Syed

    2003-01-01

    Full Text Available The present study was carried out in Chakwal, Pakistan by collecting data from randomly selected 109 flocks to investigate cost of production, gross return and net profit per layer. Majority of the buildings in the study area were rented therefore, rent per layer was added to the total cost of production instead of depreciation on building and equipments. Overall total cost of production, gross return and net profit per layer was Rs. 393.88 ± 5.36, 432.14 ± 8.01 and 38.26 ± 6.66, respectively. Rate of return over the invested capital was 27%. Mean feed cost per layer was Rs. 302.23 ± 5.01, including Rs. 10.27 ± 0.24, 29.19 ± 0.42 and 262.77 ± 5.08 for starter, grower and layer ration, respectively. Feed cost was the major component contributing 76.73% to the total cost of production. Average cost of labor, day-old chick, building rent, vaccination, therapy, miscellaneous item, electricity, bedding material and transportation was Rs. 19.90 ± 0.45, 19.75 ± 0.05, 16.25 ± 0.26, 12.80 ± 0.10, 10.90 ± 2.32, 4.35 ± 0.09, 3.15 ± 0.07, 2.65 ± 0.09 and 1.90 ± 0.08, respectively, contributing 5.05, 5.01, 4.13, 3.25, 2.77, 1.10, 0.80, 0.67 and 0.48 % to the total cost of production. Gross return from the sale of marketable eggs, culled eggs, spent/culled bird, empty bags and manure was Rs. 388.84 ± 7.91, 3.85 ± 0.01, 35.80 ± 0.23, 2.20 ± 0.04 and 1.45 ± 0.01, respectively, contributing 89.98, 0.89, 8.28, 0.51 and 0.34% to the total return. Determining the effect of different parameters on the cost of production and net profit, large flocks, Hisex strain, brood-grow and lay system of rearing, good hygienic conditions of the farm, normal stocking rate and cage system of housing wee found to give maximum gross return as well as net profit.

  20. Energy efficiency improvement target for SIC 34 - fabricated metal products

    Energy Technology Data Exchange (ETDEWEB)

    Byrer, T. G.; Billhardt, C. F.; Farkas, M. S.

    1977-03-15

    A March 15, 1977 revision of a February 15, 1977 document on the energy improvement target for the Fabricated Metal Products industry (SIC 34) is presented. A net energy savings in 1980 of 24% as compared with 1972 energy consumption in SIC 34 is considered a realistic goal. (ERA citation 04:045008)

  1. Use of MODIS Sensor Images Combined with Reanalysis Products to Retrieve Net Radiation in Amazonia

    Science.gov (United States)

    de Oliveira, Gabriel; Brunsell, Nathaniel A.; Moraes, Elisabete C.; Bertani, Gabriel; dos Santos, Thiago V.; Shimabukuro, Yosio E.; Aragão, Luiz E. O. C.

    2016-01-01

    In the Amazon region, the estimation of radiation fluxes through remote sensing techniques is hindered by the lack of ground measurements required as input in the models, as well as the difficulty to obtain cloud-free images. Here, we assess an approach to estimate net radiation (Rn) and its components under all-sky conditions for the Amazon region through the Surface Energy Balance Algorithm for Land (SEBAL) model utilizing only remote sensing and reanalysis data. The study period comprised six years, between January 2001–December 2006, and images from MODIS sensor aboard the Terra satellite and GLDAS reanalysis products were utilized. The estimates were evaluated with flux tower measurements within the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) project. Comparison between estimates obtained by the proposed method and observations from LBA towers showed errors between 12.5% and 16.4% and 11.3% and 15.9% for instantaneous and daily Rn, respectively. Our approach was adequate to minimize the problem related to strong cloudiness over the region and allowed to map consistently the spatial distribution of net radiation components in Amazonia. We conclude that the integration of reanalysis products and satellite data, eliminating the need for surface measurements as input model, was a useful proposition for the spatialization of the radiation fluxes in the Amazon region, which may serve as input information needed by algorithms that aim to determine evapotranspiration, the most important component of the Amazon hydrological balance. PMID:27347957

  2. Use of MODIS Sensor Images Combined with Reanalysis Products to Retrieve Net Radiation in Amazonia.

    Science.gov (United States)

    de Oliveira, Gabriel; Brunsell, Nathaniel A; Moraes, Elisabete C; Bertani, Gabriel; Dos Santos, Thiago V; Shimabukuro, Yosio E; Aragão, Luiz E O C

    2016-06-24

    In the Amazon region, the estimation of radiation fluxes through remote sensing techniques is hindered by the lack of ground measurements required as input in the models, as well as the difficulty to obtain cloud-free images. Here, we assess an approach to estimate net radiation (Rn) and its components under all-sky conditions for the Amazon region through the Surface Energy Balance Algorithm for Land (SEBAL) model utilizing only remote sensing and reanalysis data. The study period comprised six years, between January 2001-December 2006, and images from MODIS sensor aboard the Terra satellite and GLDAS reanalysis products were utilized. The estimates were evaluated with flux tower measurements within the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) project. Comparison between estimates obtained by the proposed method and observations from LBA towers showed errors between 12.5% and 16.4% and 11.3% and 15.9% for instantaneous and daily Rn, respectively. Our approach was adequate to minimize the problem related to strong cloudiness over the region and allowed to map consistently the spatial distribution of net radiation components in Amazonia. We conclude that the integration of reanalysis products and satellite data, eliminating the need for surface measurements as input model, was a useful proposition for the spatialization of the radiation fluxes in the Amazon region, which may serve as input information needed by algorithms that aim to determine evapotranspiration, the most important component of the Amazon hydrological balance.

  3. Daily variation in net primary production and net calcification in coral reef communities exposed to elevated pCO2

    Directory of Open Access Journals (Sweden)

    S. Comeau

    2017-07-01

    Full Text Available The threat represented by ocean acidification (OA for coral reefs has received considerable attention because of the sensitivity of calcifiers to changing seawater carbonate chemistry. However, most studies have focused on the organismic response of calcification to OA, and only a few have addressed community-level effects, or investigated parameters other than calcification, such as photosynthesis. Light (photosynthetically active radiation, PAR is a driver of biological processes on coral reefs, and the possibility that these processes might be perturbed by OA has important implications for community function. Here we investigate how CO2 enrichment affects the relationships between PAR and community net O2 production (Pnet, and between PAR and community net calcification (Gnet, using experiments on three coral communities constructed to match (i the back reef of Mo'orea, French Polynesia, (ii the fore reef of Mo'orea, and (iii the back reef of O'ahu, Hawaii. The results were used to test the hypothesis that OA affects the relationship between Pnet and Gnet. For the three communities tested, pCO2 did not affect the Pnet–PAR relationship, but it affected the intercept of the hyperbolic tangent curve fitting the Gnet–PAR relationship for both reef communities in Mo'orea (but not in O'ahu. For the three communities, the slopes of the linear relationships between Pnet and Gnet were not affected by OA, although the intercepts were depressed by the inhibitory effect of high pCO2 on Gnet. Our result indicates that OA can modify the balance between net calcification and net photosynthesis of reef communities by depressing community calcification, but without affecting community photosynthesis.

  4. Development and Application of High-Content Biological Screening for Modulators of NET Production

    Directory of Open Access Journals (Sweden)

    Ilaria J. Chicca

    2018-03-01

    Full Text Available Neutrophil extracellular traps (NETs are DNA-based antimicrobial web-like structures whose release is predominantly mediated by reactive oxygen species (ROS; their purpose is to combat infections. However, unbalanced NET production and clearance is involved in tissue injury, circulation of auto-antibodies and development of several chronic diseases. Currently, there is lack of agreement regarding the high-throughput methods available for NET investigation. This study, therefore, aimed to develop and optimize a high-content analysis (HCA approach, which can be applied for the assay of NET production and for the screening of compounds involved in the modulation of NET release. A suitable paraformaldehyde fixation protocol was established to enable HCA of neutrophils and NETs. Bespoke and in-built bioinformatics algorithms were validated by comparison with standard low-throughput approaches for application in HCA of NETs. Subsequently, the optimized protocol was applied to high-content screening (HCS of a pharmaceutically derived compound library to identify modulators of NETosis. Of 56 compounds assessed, 8 were identified from HCS for further characterization of their effects on NET formation as being either inducers, inhibitors or biphasic modulators. The effects of these compounds on naïve neutrophils were evaluated by using specific assays for the induction of ROS and NET production, while their modulatory activity was validated in phorbol 12-myristate 13-acetate-stimulated neutrophils. Results indicated the involvement of glutathione reductase, Src family kinases, molecular-target-of-Rapamycin, and mitogen-activated-protein-kinase pathways in NET release. The compounds and pathways identified may provide targets for novel therapeutic approaches for treating NET-associated pathologies.

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

    Science.gov (United States)

    Ferrell, C L; Oltjen, J W

    2008-10-01

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

  6. Towards a sustainable global energy supply infrastructure: Net energy balance and density considerations

    International Nuclear Information System (INIS)

    Kessides, Ioannis N.; Wade, David C.

    2011-01-01

    This paper employs a framework of dynamic energy analysis to model the growth potential of alternative electricity supply infrastructures as constrained by innate physical energy balance and dynamic response limits. Coal-fired generation meets the criteria of longevity (abundance of energy source) and scalability (ability to expand to the multi-terawatt level) which are critical for a sustainable energy supply chain, but carries a very heavy carbon footprint. Renewables and nuclear power, on the other hand, meet both the longevity and environmental friendliness criteria. However, due to their substantially different energy densities and load factors, they vary in terms of their ability to deliver net excess energy and attain the scale needed for meeting the huge global energy demand. The low power density of renewable energy extraction and the intermittency of renewable flows limit their ability to achieve high rates of indigenous infrastructure growth. A significant global nuclear power deployment, on the other hand, could engender serious risks related to proliferation, safety, and waste disposal. Unlike renewable sources of energy, nuclear power is an unforgiving technology because human lapses and errors can have ecological and social impacts that are catastrophic and irreversible. Thus, the transition to a low carbon economy is likely to prove much more challenging than early optimists have claimed. - Highlights: → We model the growth potential of alternative electricity supply infrastructures. → Coal is scalable and abundant but carries a heavy carbon footprint. → Renewables and nuclear meet the longevity and environmental friendliness criteria. → The low power density and intermittency of renewables limit their growth potential. → Nuclear power continues to raise concerns about proliferation, safety, and waste.

  7. Description and evaluation of a net energy intake model as a function of dietary chewing index

    DEFF Research Database (Denmark)

    Jensen, L.M.; Markussen, B.; Nielsen, N.I.

    2016-01-01

    Previously, a linear relationship has been found between net energy intake (NEI) and dietary chewing index (CI) of the diet for different types of cattle. Therefore, we propose to generalize and calibrate this relationship into a new model for direct prediction of NEI by dairy cows from CI values...... (CINE; min/MJ of NE). Furthermore, we studied the forage-to-concentrate substitution rate in this new NEI model. To calibrate the model on a diverse set of situations, we built a database of mean intake from 14 production experiments with a total of 986 primi- and multiparous lactating dairy cows......, and disturbance, across and within experiments on independent data from 19 experiments including 812 primi- and multiparous lactating dairy cows of different breeds fed 80 different diets ad libitum. The NEI model predicted NEI with an MSPE of 8% of observed, and across the 19 experiments the error central...

  8. Army Net Zero: Energy Roadmap and Program Summary, Fiscal Year 2013 (Brochure)

    Energy Technology Data Exchange (ETDEWEB)

    2014-08-01

    The U.S. Army (Army) partnered with the National Renewable Energy Laboratory (NREL) and the U.S. Army Corps of Engineers to assess opportunities for increasing energy security through improved energy efficiency and optimized renewable energy strategies at nine installations across the Army's portfolio. Referred to as Net Zero Energy Installations (NZEIs), these projects demonstrate and validate energy efficiency and renewable energy technologies with approaches that can be replicated across DOD and other Federal agencies, setting the stage for broad market adoption. This report summarizes the results of the energy project roadmaps developed by NREL, shows the progress each installation could make in achieving Net Zero Energy by 2020, and presents lessons learned and unique challenges from each installation.

  9. Photosynthetic behavior, growth and essential oil production of Melissa officinalis L. cultivated under colored shade nets

    OpenAIRE

    Graziele C Oliveira; Willyam L Vieira; Suzana C Bertolli; Ana Claudia Pacheco

    2016-01-01

    The modulation of light is of importance during cultivation of medicinal plants to obtain desirable morphological and physiological changes associated with the maximum production of active principles. This study aimed to evaluate the effect of the light spectrum transmitted by colored shade nets on growth, essential oil production and photosynthetic behavior in plants of lemon balm (Melissa officinalis L.) Plants were cultivated in pots for 4-mo under black, red, and blue nets with 50% shadin...

  10. EcoVillage: A Net Zero Energy Ready Community

    Energy Technology Data Exchange (ETDEWEB)

    Arena, L. [Consortium for Advanced Residential Buildings, Norwalk, CT (United States); Faakye, O. [Consortium for Advanced Residential Buildings, Norwalk, CT (United States)

    2015-02-01

    CARB is working with the EcoVillage co-housing community in Ithaca, New York, on their third neighborhood called the Third Residential EcoVillage Experience (TREE). This community scale project consists of 40 housing units --15 apartments and 25 single family residences. The community is pursuing certifications for DOE Zero Energy Ready Home, U.S. Green Building Council Leadership in Energy and Environmental Design Gold, and ENERGY STAR for the entire project. Additionally, seven of the 25 homes, along with the four-story apartment building and community center, are being constructed to the Passive House (PH) design standard.

  11. Working Towards Net Zero Energy at Fort Irwin, CA

    Science.gov (United States)

    2010-09-01

    sub- metering of their energy use. • MERV 15 – 16 air filtration would be used to reduce the impact of very fine desert dust on the heat transfer coil...use and 1,420,414 KWh/yr electrical use. The electrical use can be offset further with waste to energy cogeneration , or the use of a trigeneration...Biogas cogeneration plant (25 kWth / 50 kWth): $70,000–$90,000 Fermentation plant (300 – 400 t/yr): $150,000 7.3.2 Usable energy 200 MWh electricity

  12. Consumer Unit for Low Energy District Heating Net

    DEFF Research Database (Denmark)

    Paulsen, Otto; Fan, Jianhua; Furbo, Simon

    2008-01-01

    to reduce heat loss in the network. The consumer’s installation is a unit type with an accumulation tank for smoothing the heat load related to the domestic hot water. The building heat load is delivered by an under-floor heating system. The heavy under-floor heating system is assumed to smooth the room...... heat load on a daily basis, having a flow temperature control based on outdoor climate. The unit is designed for a near constant district heating water flow. The paper describes two concepts. The analyses are based on TRNSYS (Klein et al., 2006) simulation, supplied with laboratory verification......A low energy/ low temperature consumer installation is designed and analyzed. The consumer type is a low energy single family house 145 m2 with annual energy consumption in the range of 7000 kWh, incl. domestic hot water in a 2800 degree day climate. The network is an extreme low temperature system...

  13. Net Energy Payback and CO2 Emissions from Three Midwestern Wind Farms: An Update

    International Nuclear Information System (INIS)

    White, Scott W.

    2006-01-01

    This paper updates a life-cycle net energy analysis and carbon dioxide emissions analysis of three Midwestern utility-scale wind systems. Both the Energy Payback Ratio (EPR) and CO 2 analysis results provide useful data for policy discussions regarding an efficient and low-carbon energy mix. The EPR is the amount of electrical energy produced for the lifetime of the power plant divided by the total amount of energy required to procure and transport the materials, build, operate, and decommission the power plants. The CO 2 analysis for each power plant was calculated from the life-cycle energy input data.A previous study also analyzed coal and nuclear fission power plants. At the time of that study, two of the three wind systems had less than a full year of generation data to project the life-cycle energy production. This study updates the analysis of three wind systems with an additional four to eight years of operating data.The EPR for the utility-scale wind systems ranges from a low of 11 for a two-turbine system in Wisconsin to 28 for a 143-turbine system in southwestern Minnesota. The EPR is 11 for coal, 25 for fission with gas centrifuge enriched uranium and 7 for gaseous diffusion enriched uranium. The normalized CO 2 emissions, in tonnes of CO 2 per GW e h, ranges from 14 to 33 for the wind systems, 974 for coal, and 10 and 34 for nuclear fission using gas centrifuge and gaseous diffusion enriched uranium, respectively

  14. Net energy payback and CO2 emissions from three midwestern wind farms: An update

    Science.gov (United States)

    White, S.W.

    2006-01-01

    This paper updates a life-cycle net energy analysis and carbon dioxide emissions analysis of three Midwestern utility-scale wind systems. Both the Energy Payback Ratio (EPR) and CO2 analysis results provide useful data for policy discussions regarding an efficient and low-carbon energy mix. The EPR is the amount of electrical energy produced for the lifetime of the power plant divided by the total amount of energy required to procure and transport the materials, build, operate, and decommission the power plants. The CO2 analysis for each power plant was calculated from the life-cycle energy input data. A previous study also analyzed coal and nuclear fission power plants. At the time of that study, two of the three wind systems had less than a full year of generation data to project the life-cycle energy production. This study updates the analysis of three wind systems with an additional four to eight years of operating data. The EPR for the utility-scale wind systems ranges from a low of 11 for a two-turbine system in Wisconsin to 28 for a 143-turbine system in southwestern Minnesota. The EPR is 11 for coal, 25 for fission with gas centrifuge enriched uranium and 7 for gaseous diffusion enriched uranium. The normalized CO2 emissions, in tonnes of CO2 per GW eh, ranges from 14 to 33 for the wind systems, 974 for coal, and 10 and 34 for nuclear fission using gas centrifuge and gaseous diffusion enriched uranium, respectively. ?? Springer Science+Business Media, LLC 2007.

  15. Mineralizing urban net-zero water treatment: Field experience for energy-positive water management.

    Science.gov (United States)

    Wu, Tingting; Englehardt, James D

    2016-12-01

    An urban net-zero water treatment system, designed for energy-positive water management, 100% recycle of comingled black/grey water to drinking water standards, and mineralization of hormones and other organics, without production of concentrate, was constructed and operated for two years, serving an occupied four-bedroom, four-bath university residence hall apartment. The system comprised septic tank, denitrifying membrane bioreactor (MBR), iron-mediated aeration (IMA) reactor, vacuum ultrafilter, and peroxone or UV/H 2 O 2 advanced oxidation, with 14% rainwater make-up and concomitant discharge of 14% of treated water (ultimately for reuse in irrigation). Chemical oxygen demand was reduced to 12.9 ± 3.7 mg/L by MBR and further decreased to below the detection limit (treatment. The process produced a mineral water meeting 115 of 115 Florida drinking water standards that, after 10 months of recycle operation with ∼14% rainwater make-up, had a total dissolved solids of ∼500 mg/L, pH 7.8 ± 0.4, turbidity 0.12 ± 0.06 NTU, and NO 3 -N concentration 3.0 ± 1.0 mg/L. None of 97 hormones, personal care products, and pharmaceuticals analyzed were detected in the product water. For a typical single-home system with full occupancy, sludge pumping is projected on a 12-24 month cycle. Operational aspects, including disinfection requirements, pH evolution through the process, mineral control, advanced oxidation by-products, and applicability of point-of-use filters, are discussed. A distributed, peroxone-based NZW management system is projected to save more energy than is consumed in treatment, due largely to retention of wastewater thermal energy. Recommendations regarding design and operation are offered. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Energy use in citrus production of Mazandaran province in Iran ...

    African Journals Online (AJOL)

    The total energy requirement under citrus farming was 17,112.2 MJ ha-1, whereas 36.3 and 33.62% was consumed due to fertilisers and pesticides, respectively. Renewable energy was about 12% of total energy input. The energy ratio, productivities, specific and net energy gain were 1.71, 0.905, 1.104 and 12,251.4 MJ ...

  17. PNC Financial Services - Net-Zero Energy Bank Branch

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2013-03-01

    PNC has opened a zero-energy building that is 57% more efficient than ASHRAE 90.1-2004. Exterior features include shading to control glare from sunlight and photovoltaic solar panels to produce as much electricity as the building consumes annually.

  18. Energy management for vehicle power net with flexible electric load demand

    NARCIS (Netherlands)

    Kessels, J.T.B.A.; Bosch, van den P.P.J.; Koot, M.W.T.; Jager, de A.G.

    2005-01-01

    The electric power demand in road vehicles increases rapidly and to supply all electric loads efficiently, energy management (EM) turns out to be a necessity. In general, EM exploits the storage capacity of a buffer connected to the vehicle's power net, such that energy is stored or retrieved at

  19. International Clean Energy System Using Hydrogen Conversion (WE-NET). subtask 2. Research study on promotion of international cooperation; Suiso riyo kokusai clean energy system gijutsu (WE-NET). subtask 2. Kokusai kyoryoku suishin no tame no chosa kento

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    This paper describes the research result on promotion of international cooperation in the WE-NET project in fiscal 1996. The WE-NET project aims at development of the total system for hydrogen production, transport, storage and utilization, and construction of the earth-friendly innovative global clean energy network integrating elemental technologies. Since the standpoint is different between latent resource supplying countries and technology supplying countries, the WE-NET project should be constantly promoted under international understanding and cooperation. The committee distributed the annual summary report prepared by NEDO to overseas organizations, and made positive PR activities in the 11th World Conference and others. The committee made the evaluation on the improvement effect of air pollution by introducing a hydrogen vehicle in combination with Stanford University, and preparation of PR video tapes for hydrogen energy. Preliminary arrangement of Internet home pages, establishment of a long-term vision for international cooperation, and proposal toward the practical WE-NET are also made. 9 figs., 13 tabs.

  20. Impacts of tropospheric ozone and climate change on net primary productivity and net carbon exchange of China’s forest ecosystems

    Science.gov (United States)

    Wei Ren; Hanqin Tian; Bo Tao; Art Chappelka; Ge Sun; et al

    2011-01-01

    Aim We investigated how ozone pollution and climate change/variability have interactively affected net primary productivity (NPP) and net carbon exchange (NCE) across China’s forest ecosystem in the past half century. Location Continental China. Methods Using the dynamic land ecosystem model (DLEM) in conjunction with 10-km-resolution gridded historical data sets (...

  1. Fiscal 1994 achievement report. International Clean Energy Network Using Hydrogen Conversion (WE-NET) technology

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-03-01

    Research and development was made for the WE-NET (World Energy Network) project which aims to carry out hydrogen production, transportation, and supply to consumers, by the use of renewable energy. In this fiscal year, surveys were conducted of the status of research and development in each of the fields, and research was started on element technologies in some of the fields. Under subtask 1, surveys and studies were started for pilot plant phase 2. Under subtask 2, an international symposium was held for the enhancement of technical information exchange. Under subtask 3, a liquid hydrogen system conceptual design was prepared for the estimation of facility cost, etc. Under subtask 4, small experimental cells were fabricated for evaluating electrode bonding methods. Under subtask 5, studies were made about the processes of the helium Brayton cycle and hydrogen Claude cycle for the development of a large-scale hydrogen liquefaction plant. Under subtasks 6-9, furthermore, surveys and studies were conducted about low-temperature substance technology, hydrogen energy, hydrogen combustion turbines, and so forth. (NEDO)

  2. The Influence of Output Variability from Renewable Electricity Generation on Net Energy Calculations

    Directory of Open Access Journals (Sweden)

    Hannes Kunz

    2014-01-01

    Full Text Available One key approach to analyzing the feasibility of energy extraction and generation technologies is to understand the net energy they contribute to society. These analyses most commonly focus on a simple comparison of a source’s expected energy outputs to the required energy inputs, measured in the form of energy return on investment (EROI. What is not typically factored into net energy analysis is the influence of output variability. This omission ignores a key attribute of biological organisms and societies alike: the preference for stable returns with low dispersion versus equivalent returns that are intermittent or variable. This biologic predilection for stability, observed and refined in academic financial literature, has a direct relationship to many new energy technologies whose outputs are much more variable than traditional energy sources. We investigate the impact of variability on net energy metrics and develop a theoretical framework to evaluate energy systems based on existing financial and biological risk models. We then illustrate the impact of variability on nominal energy return using representative technologies in electricity generation, with a more detailed analysis on wind power, where intermittence and stochastic availability of hard-to-store electricity will be factored into theoretical returns.

  3. Geothermal Energy as source or energy production

    International Nuclear Information System (INIS)

    Lozano, E.

    1998-01-01

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

  4. Neural-net based unstable machine identification using individual energy functions. [Transient disturbances in power systems

    Energy Technology Data Exchange (ETDEWEB)

    Djukanovic, M [Institut Nikola Tesla, Belgrade (Yugoslavia); Sobajic, D J; Pao, Yohhan [Case Western Reserve Univ., Cleveland, OH (United States)

    1991-10-01

    The identification of the mode of instability plays an essential role in generating principal energy boundary hypersurfaces. We present a new method for unstable machine identification based on the use of supervised learning neural-net technology, and the adaptive pattern recognition concept. It is shown that using individual energy functions as pattern features, appropriately trained neural-nets can retrieve the reliable characterization of the transient process including critical clearing time parameter, mode of instability and energy margins. Generalization capabilities of the neural-net processing allow for these assessments to be made independently of load levels. The results obtained from computer simulations are presented using the New England power system, as an example. (author).

  5. A review of net metering mechanism for electricity renewable energy sources

    Energy Technology Data Exchange (ETDEWEB)

    Poullikkas, Andreas; Kourtis, George; Hadjipaschalis, Ioannis [Electricity Authority of Cyprus, P.O. Box 24506, 1399 Nicosia (Cyprus)

    2013-07-01

    In this work, an overview of the net metering mechanism for renewable energy sources for power generation (RES-E) systems is carried out. In particular, the net metering concept is examined with its benefits and misconceptions. Furthermore, a survey of the current operational net metering schemes in different countries in the world, such as, in Europe, USA, Canada, Thailand and Australia, is carried out. The survey indicated that there are different net metering mechanisms depending on the particularities of each country (or state in the case of USA). Especially, in Europe, only five countries are using net metering in a very simple form, such as, any amount of energy produced by the eligible RES-E technology is compensated from the energy consumed by the RES-E producer, which results to either a less overall electricity bill or to an exception in payment energy taxes. In the USA and the USA territories, any customer’s net excess generation is credited to the customer’s next electricity bill for a 12-month billing cycle at various rates or via a combination between rates. The actual type of net excess generation (NEG) credit is decided by a number of set criteria, such as the type of RES-E technology, the RES-E capacity limit, the type of customer and the type of utility. Regarding any excess credit at the end of the 12-month billing cycle, this is either granted to the utilities, or carries over indefinitely to the customer’s next electricity bill, or is reconciled annually at any rate, or provides an option to the customer to choose between the last two options.

  6. Description and evaluation of a net energy intake model as a function of dietary chewing index

    DEFF Research Database (Denmark)

    Jensen, Laura Mie; Markussen, Bo; Nielsen, N. I.

    2016-01-01

    Previously, a linear relationship has been found between net energy intake (NEI) and dietary chewing index (CI) of the diet for different types of cattle. Therefore, we propose to generalize and calibrate this relationship into a new model for direct prediction of NEI by dairy cows from CI values...... a value of 2, implying a constant maximum daily chewing time. The intercept NEI0 in the regression of NEI on CINE may be interpreted as metabolic net energy intake capacity of the cows fed without physical constraints on intake. Based on experimental data, the maximum chewing time was estimated as 1...

  7. DOE Zero Energy Ready Home Case Study: One Sky Homes — Cottle Zero Net Energy Home, San Jose, CA

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2014-09-01

    This builder took home the Grand Winner prize in the Custom Builder category in the 2014 Housing Innovation Awards for its high performance building science approach. The builder used insulated concrete form blocks to create the insulated crawlspace foundation for its first DOE Zero Energy Ready Home, the first net zero energy new home certified in the state of California.

  8. Computing the Net Primary Productivity for a Savanna- Dominated ...

    African Journals Online (AJOL)

    komla

    2003-05-19

    May 19, 2003 ... productivity of CO2 (between 1–2% per year) continues, a doubling of the CO2 ... The work ... Numerous isotope mass balance equa-tions are proposed to ..... Terrestrial ecoregions of the world: a new map of life on earth.

  9. Dynamics of System of Systems and Applications to Net Zero Energy Facilities

    Science.gov (United States)

    2017-10-05

    collections and applied it in a variety of ways to energy - related problems. 1. REPORT DATE (DD-MM-YYYY) 4. TITLE AND SUBTITLE 13. SUPPLEMENTARY...UU UU 05-10-2017 1-Oct-2011 30-Sep-2016 Dynamics of System of Systems and Applications to Net Zero Energy Facilities The views, opinions and/or...Research Triangle Park, NC 27709-2211 Koopman operator analysis, Energy systems REPORT DOCUMENTATION PAGE 11. SPONSOR/MONITOR’S REPORT NUMBER(S) 10

  10. Net change in carbon emissions with increased wood energy use in the United States

    Science.gov (United States)

    Prakash Nepal; David N. Wear; Kenneth E. Skog

    2014-01-01

    Use of wood biomass for energy results in carbon (C) emissions at the time of burning and alters C stocks on the land because of harvest, regrowth, and changes in land use or management. This study evaluates the potential effects of expanded woody biomass energy use (for heat and power) on net C emissions over time. A scenario with increased wood energy use is compared...

  11. Site-level evaluation of satellite-based global terrestrial gross primary production and net primary production monitoring.

    Science.gov (United States)

    David P. Turner; William D. Ritts; Warren B. Cohen; Thomas K. Maeirsperger; Stith T. Gower; Al A. Kirschbaum; Steve W. Runnings; Maosheng Zhaos; Steven C. Wofsy; Allison L. Dunn; Beverly E. Law; John L. Campbell; Walter C. Oechel; Hyo Jung Kwon; Tilden P. Meyers; Eric E. Small; Shirley A. Kurc; John A. Gamon

    2005-01-01

    Operational monitoring of global terrestrial gross primary production (GPP) and net primary production (NPP) is now underway using imagery from the satellite-borne Moderate Resolution Imaging Spectroradiometer (MODIS) sensor. Evaluation of MODIS GPP and NPP products will require site-level studies across a range of biomes, with close attention to numerous scaling...

  12. Seasonal shift in net ecosystem production in a tropical estuary

    Digital Repository Service at National Institute of Oceanography (India)

    Ram, A.S.P.; Nair, S.; Chandramohan, D.

    ) and community respiration (R). Measurements of these variables are a prerequisite to assess the trophic status of aquatic ecosystems. Del Giorgio et al. (1997) suggested that metabolic balance depends on the primary productivity of the system. The rate...), and heterotrophy is not restricted to oligotrophic sys- tems. Of late, there has been considerable debate on the role of planktonic communities as sources (del Giorgio et al. 1997; Duarte et al. 2001) or sinks (Williams 1998) of carbon in subtropical and temperate...

  13. Estimation of livestock appropriation of net primary productivity in Texas Drylands

    Science.gov (United States)

    Robert Washington-Allen; Jody Fitzgerald; Stephanie Grounds; Faisar Jihadi; John Kretzschmar; Kathryn Ramirez; John Mitchell

    2009-01-01

    The ecological state of US Drylands is unknown. This research is developing procedures to determine the impact of the ecological footprint of grazing livestock on the productive capacity of US Drylands. A pilot geodatabase was developed for the state of Texas that includes 2002 data for county boundaries, net primary productivity (NPP) derived from the Moderate...

  14. The operational performance of “net zero energy building”: A study in China

    International Nuclear Information System (INIS)

    Zhou, Zhihua; Feng, Lei; Zhang, Shuzhen; Wang, Chendong; Chen, Guanyi; Du, Tao; Li, Yasong; Zuo, Jian

    2016-01-01

    Highlights: • Choose energy efficiency technology in office building to implement “nZEB”. • Simulate its energy consumption. • Study on the operational performance. • Optimize its running. - Abstract: There is no lack of studies on “net zero energy buildings” (“nZEB”). However, the vast majority of these studies focus on theories and simulation. The actual operational performance of “net zero energy building” during occupation has been largely overlooked by previous studies. This study aims to investigate the operational performance of net “zero energy buildings” via the case study of an office building in Tianjin, China. Using simulation, the energy consumption of the building at design phase was estimated and a solar photovoltaic (PV) system was selected. A whole year operation of the occupied building showed that energy consumption of the case building was much higher than the energy generated from the solar PV system. This was mainly due to three issues. Firstly, the equipment was different in terms of category, quantity and running time between operation and design stages, leading to considerable underestimate of energy consumption at the design stage. Secondly, the operational strategies need to be further improved in order to regulate users’ behaviors. Thirdly, the efficiency of solar PV system was substantially reduced due to poor atmospheric environment (i.e. haze weather). Therefore, during the design process of “net zero energy buildings”, it is imperative to ensure that the energy simulation accurately reflects how the building will actually operate once occupied. The research also revealed other barriers to the design and implementation of “nZEB” in China, such as extra efforts required for effective communicating the capacity of the HVAC design and systems to clients, and the increased cost of “nZEB” (e.g. solar PV system) particularly for public buildings. Finally, the solar radiation intensity of standard

  15. Assessing the engineering performance of affordable net-zero energy housing

    Science.gov (United States)

    Wallpe, Jordan P.

    The purpose of this research was to evaluate affordable technologies that are capable of providing attractive, cost-effective energy savings to the housing industry. The research did so by investigating the 2011 Solar Decathlon competition, with additional insight from the Purdue INhome. Insight from the Purdue INhome verified the importance of using a three step design process to design a net-zero energy building. In addition, energy consumption values of the INhome were used to compare and contrast different systems used in other houses. Evaluation of unbiased competition contests gave a better understanding of how a house can realistically reach net-zero. Upon comparison, off-the-shelf engineering systems such as super-efficient HVAC units, heat pump hot water heaters, and properly designed photovoltaic arrays can affordably enable a house to become net-zero. These important and applicable technologies realized from the Solar Decathlon will reduce the 22 percent of all energy consumed through the residential sector in the United States. In conclusion, affordable net-zero energy buildings can be built today with commitment from design professionals, manufacturers, and home owners.

  16. 1999 annual summary report on results. International clean energy network using hydrogen conversion (WE-NET)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    The R and D were conducted on the international clean network (WE-NET) which aims at producing hydrogen by using renewable energy, converting it in a form suitable for transportation and supplying the hydrogen to places of quantity consumption of energy. The FY 1999 results were summed up. In the system evaluation, study was made on sodium carbonate electrolysis by-producing hydrogen, the supply amount by coke oven by-producing hydrogen and the economical efficiency, etc. As to the safety, study was made on the design of hydrogen supply stand model. Concerning the power generation technology, study was conducted on element technologies of injection valve, exhaust gas condenser, gas/liquid separator, etc. Relating to the hydrogen fueled vehicle system, the shock destructive testing, etc. were conducted on the hydrogen tank and hydrogen storage alloys. Besides, a lot of R and D were carried out of pure water use solid polymer fuel cells, hydrogen stand, hydrogen production technology, hydrogen transportation/storage technology, low temperature materials, transportation/storage using hydrogen storage alloys, innovative advanced technology, etc. (NEDO)

  17. Increased light-use efficiency sustains net primary productivity of shaded coffee plants in agroforestry system.

    Science.gov (United States)

    Charbonnier, Fabien; Roupsard, Olivier; le Maire, Guerric; Guillemot, Joannès; Casanoves, Fernando; Lacointe, André; Vaast, Philippe; Allinne, Clémentine; Audebert, Louise; Cambou, Aurélie; Clément-Vidal, Anne; Defrenet, Elsa; Duursma, Remko A; Jarri, Laura; Jourdan, Christophe; Khac, Emmanuelle; Leandro, Patricia; Medlyn, Belinda E; Saint-André, Laurent; Thaler, Philippe; Van Den Meersche, Karel; Barquero Aguilar, Alejandra; Lehner, Peter; Dreyer, Erwin

    2017-08-01

    In agroforestry systems, shade trees strongly affect the physiology of the undergrown crop. However, a major paradigm is that the reduction in absorbed photosynthetically active radiation is, to a certain extent, compensated by an increase in light-use efficiency, thereby reducing the difference in net primary productivity between shaded and non-shaded plants. Due to the large spatial heterogeneity in agroforestry systems and the lack of appropriate tools, the combined effects of such variables have seldom been analysed, even though they may help understand physiological processes underlying yield dynamics. In this study, we monitored net primary productivity, during two years, on scales ranging from individual coffee plants to the entire plot. Absorbed radiation was mapped with a 3D model (MAESPA). Light-use efficiency and net assimilation rate were derived for each coffee plant individually. We found that although irradiance was reduced by 60% below crowns of shade trees, coffee light-use efficiency increased by 50%, leaving net primary productivity fairly stable across all shade levels. Variability of aboveground net primary productivity of coffee plants was caused primarily by the age of the plants and by intraspecific competition among them (drivers usually overlooked in the agroforestry literature) rather than by the presence of shade trees. © 2017 John Wiley & Sons Ltd.

  18. Energy production in stars

    International Nuclear Information System (INIS)

    Bethe, Hans.

    1977-01-01

    Energy in stars is released partly by gravitation, partly by nuclear reactions. For ordinary stars like our sun, nuclear reactions predominate. However, at the end of the life of a star very large amounts of energy are released by gravitational collapse; this can amount to as much as 10 times the total energy released nuclear reactions. The rotational energy of pulsars is a small remnant of the energy of gravitation. The end stage of small stars is generally a white dwarf, of heavy stars a neutron star of possibly a black hole

  19. ENERGY STAR Certified Roof Products

    Data.gov (United States)

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

  20. A net-zero building application and its role in exergy-aware local energy strategies for sustainability

    International Nuclear Information System (INIS)

    Kılkış, Şiir

    2012-01-01

    Highlights: ► Net-zero exergy targets are put forth for more energy-sufficient buildings and districts. ► A premier building that is the first LEED Platinum building in Turkey exemplifies this target. ► The building integrates low-exergy measures with PV/BIPV, CHP, GSHP, solar collectors and TES. ► Two districts in the south heating network of Stockholm are compared with this technology bundle. ► Net-zero exergy targets are related to a re-structuring of an exergy-aware energy value chain. - Abstract: Based on two case studies, this paper explores the nexus of exergy, net-zero targets, and sustainable cities as a means of analyzing the role of exergy-aware strategies at the building and district level. The first case study is a premier building in Ankara that is ready to meet the net-zero exergy target. It is also the first building in Turkey to receive the highest Platinum rating in Leadership in Energy and Environmental Design. A net-zero exergy building (NZEXB) is a building that has an annual sum of net-zero exergy transfer across the building-district boundary. This new target is made possible by lowered annual exergy consumption, (AEXC), and increased on-site production from a bundle of sustainable energy technologies. The modeled results of the building indicate that the reduced AEXC of 60 kW h/m 2 yr is met with on-site production of 62 kW h/m 2 yr. On-site production includes PV and building integrated PV, a micro-wind turbine, combined heat and power, GSHP, and solar collectors. Diversified thermal energy storage tanks further facilitate the exergy supply to meet with the exergy demand. The results of this case study provide key lessons to structure an energy value chain that is more aware of exergy, which are up-scalable to the district level when the bundle of sustainable energy technologies is zoomed out across a larger spatial area. These key lessons are then compared with the second case study of two districts in the south heating network

  1. Life Cycle Cost Analysis of a Multi-Storey Residential Net Zero Energy Building in Denmark

    DEFF Research Database (Denmark)

    Marszal, Anna Joanna; Heiselberg, Per

    2011-01-01

    demand and three alternatives of energy supply systems: (1) photovoltaic installation with photovoltaic/solar thermal collectors and an ambient air/solar source heat pump; (2) photovoltaic installation with a ground-source heat pump; (3) photovoltaic installation with district heating grid. The results...... source of heat than a heat pump for the Net ZEB....

  2. Achieving informed decision-making for net zero energy buildings design using building performance simulation tools

    NARCIS (Netherlands)

    Attia, S.G.; Gratia, E.; De Herde, A.; Hensen, J.L.M.

    2013-01-01

    Building performance simulation (BPS) is the basis for informed decision-making of Net Zero Energy Buildings (NZEBs) design. This paper aims to investigate the use of building performance simulation tools as a method of informing the design decision of NZEBs. The aim of this study is to evaluate the

  3. Energy system analysis of a pilot net-zero exergy district

    International Nuclear Information System (INIS)

    Kılkış, Şiir

    2014-01-01

    Highlights: • Östra Sala backe is analyzed as a pilot district for the net-zero exergy target. • An analysis tool is developed for proposing an energy system for Östra Sala backe. • A total of 8 different measures are included and integrated in the energy system. • The exergy produced on-site is 49.7 GW h, the annual exergy consumed is 54.3 GW h. • The average value of the level of exergy match in the supply and demand is 0.84. - Abstract: The Rational Exergy Management Model (REMM) provides an analytical model to curb primary energy spending and CO 2 emissions by means of considering the level of match between the grade/quality of energy resources (exergy) on the supply and demand sides. This model is useful for developing forward-looking concepts with an energy systems perspective. One concept is net-zero exergy districts, which produce as much energy at the same grade or quality as consumed on an annual basis. This paper analyzes the district of Östra Sala backe in Uppsala Municipality in Sweden as a pilot, near net-zero exergy district. The district is planned to host 20,000 people at the end of four phases. The measures that are considered include an extension of the combined heat and power based district heating and cooling network, heat pumps driven on renewable energy, district heating driven white goods, smart home automation, efficient lighting, and bioelectricity driven public transport. A REMM Analysis Tool for net-zero exergy districts is developed and used to analyze 5 scenarios based on a Net-Zero Exergy District Option Index. According to the results, a pilot concept for the first phase of the project is proposed. This integrates a mix of 8 measures considering an annual electricity load of 46.0 GW h e and annual thermal load of 67.0 GW h t . The exergy that is produced on-site with renewable energy sources is 49.7 GW h and the annual exergy consumed is 54.3 GW h. The average value of the level of match between the demand and supply of

  4. Net carbon dioxide emissions from alternative firewood-production systems in Australia

    International Nuclear Information System (INIS)

    Paul, K.I.; Booth, T.H.; Jovanovic, T.; Polglase, P.J.; Elliott, A.; Kirschbaum, M.U.F.

    2006-01-01

    The use of firewood for domestic heating has the potential to reduce fossil-fuel use and associated CO 2 emissions. The level of possible reductions depends upon the extent to which firewood off-sets the use of fossil fuels, the efficiency with which wood is burnt, and use of fossil fuels for collection and transport of firewood. Plantations grown for firewood also have a cost of emissions associated with their establishment. Applying the FullCAM model and additional calculations, these factors were examined for various management scenarios under three contrasting firewood production systems (native woodland, sustainably managed native forest, and newly established plantations) in low-medium rainfall (600-800mm) regions of south-eastern Australia. Estimates of carbon dioxide emissions per unit of heat energy produced for all scenarios were lower than for non-renewable energy sources (which generally emit about 0.3-1.0kgCO 2 kWh -1 ). Amongst the scenarios, emissions were greatest when wood was periodically collected from dead wood in woodlands (0.11kgCO 2 kWh -1 ), and was much lower when obtained from harvest residues and dead wood in native forests ( 2 kWh -1 ). When wood was obtained from plantations established on previously cleared agricultural land, use of firewood led to carbon sequestration equivalent to -0.06kgCO 2 kWh -1 for firewood obtained from a coppiced plantation, and -0.17kgCO 2 kWh -1 for firewood collected from thinnings, slash and other residue in a plantation grown for sawlog production. An uncertainty analysis, where inputs and assumptions were varied in relation to a plausible range of management practices, identified the most important influencing factors and an expected range in predicted net amount of CO 2 emitted per unit of heat energy produced from burning firewood. (author)

  5. Hydrogen Economy Model for Nearly Net-Zero Cities with Exergy Rationale and Energy-Water Nexus

    Directory of Open Access Journals (Sweden)

    Birol Kılkış

    2018-05-01

    Full Text Available The energy base of urban settlements requires greater integration of renewable energy sources. This study presents a “hydrogen city” model with two cycles at the district and building levels. The main cycle comprises of hydrogen gas production, hydrogen storage, and a hydrogen distribution network. The electrolysis of water is based on surplus power from wind turbines and third-generation solar photovoltaic thermal panels. Hydrogen is then used in central fuel cells to meet the power demand of urban infrastructure. Hydrogen-enriched biogas that is generated from city wastes supplements this approach. The second cycle is the hydrogen flow in each low-exergy building that is connected to the hydrogen distribution network to supply domestic fuel cells. Make-up water for fuel cells includes treated wastewater to complete an energy-water nexus. The analyses are supported by exergy-based evaluation metrics. The Rational Exergy Management Efficiency of the hydrogen city model can reach 0.80, which is above the value of conventional district energy systems, and represents related advantages for CO2 emission reductions. The option of incorporating low-enthalpy geothermal energy resources at about 80 °C to support the model is evaluated. The hydrogen city model is applied to a new settlement area with an expected 200,000 inhabitants to find that the proposed model can enable a nearly net-zero exergy district status. The results have implications for settlements using hydrogen energy towards meeting net-zero targets.

  6. Photosynthetic behavior, growth and essential oil production of Melissa officinalis L. cultivated under colored shade nets

    Directory of Open Access Journals (Sweden)

    Graziele C Oliveira

    2016-03-01

    Full Text Available The modulation of light is of importance during cultivation of medicinal plants to obtain desirable morphological and physiological changes associated with the maximum production of active principles. This study aimed to evaluate the effect of the light spectrum transmitted by colored shade nets on growth, essential oil production and photosynthetic behavior in plants of lemon balm (Melissa officinalis L. Plants were cultivated in pots for 4-mo under black, red, and blue nets with 50% shading, and full sunlight exposure. Biometric and anatomical variables, essential oil yield, global solar radiation, photon flux density, chlorophyll content, and gas exchange parameters were measured in M. officinalis leaves. The results showed that despite being considered a partial shade plant, this species is able to adapt to full sunlight conditions without increasing biomass production. The spectral changes provided by colored shade nets did not caused any noticeable change in leaf anatomy of M. officinalis. However, the use of blue net resulted in increments of 116% in plant height, 168% in leaf area, 42% in chlorophyll content and 30% in yield of essential oil in lemon balm plants. These plant's qualities make the use of blue net a cultivation practice suitable for commercial use.

  7. Neural nets with varying topology for high energy particle recognition. Theory and applications

    International Nuclear Information System (INIS)

    Perrone, A.L.; Basti, G.; Messi, R.; Paoluzi, L.; Picozza, P.

    1995-01-01

    In this paper we propose a strategy to solve the problem of parallel compuation based on a dynamic definition of the net topology showing its effectiveness for problems of particle track recognition in high-energy physics. In this way, we can maintain the linear architecture like in the geometric perceptron, but with a partial and dynamic connectivity so to overcome the intrinsic limiations of the geometric perceptron. Namely, the computation is truly parallel because of the partial connectivity but the net topology is always the optimal one because of its dynamic redefinition on the single input pattern. For these properties, we call this new architecture dynamic perceptron

  8. The production of Physalis spp. seedlings grown under different-colored shade nets

    Directory of Open Access Journals (Sweden)

    Daniel Fernandes da Silva

    2016-04-01

    Full Text Available The objective of this study was to evaluate the production of seedlings of Physalis L. species under different-colored shade nets. Four shade nets individually stained white, blue, red and black, all with 50% shading, were used in this study, and an additional  treatment (control was used in which seedlings were grown in full sun. The study examined four species of Physalis, namely, P. peruviana, P. pubescens, P. minima and P. ixocarpa. The experiment followed a randomized block design with three blocks and 25 seeds per plot. The species were sown in styrofoam trays. Germination was monitored daily to calculate the Emergency Velocity Index (EVI and stabilize the overall percentage of emergence. Height, stem diameter, number of leaves, leaf area index and dry mass of seedlings were assessed at 50 days after sowing. The study found that these species react differently to changes in the light spectrum. Seedlings of P. peruviana should be grown under a white or red shade net; of P. pubescens under a white or black shade net; of P. minima under a white, red or black shade net; and of P. ixocarpa under a white shade net. For all species, 50% shade should be used.

  9. The potential of centrifugal casting for the production of near net shape uranium parts

    International Nuclear Information System (INIS)

    Robertson, E.

    1993-09-01

    This report was written to provide a detailed summary of a literature survey on the near net shape casting process of centrifugal casting. Centrifugal casting is one potential casting method which could satisfy the requirements of the LANL program titled Near Net Shape Casting of Uranium for Reduced Environmental, Safety and Health Impact. In this report, centrifugal casting techniques are reviewed and an assessment of the ability to achieve the near net shape and waste minimization goals of the LANL program by using these techniques is made. Based upon the literature reviewed, it is concluded that if properly modified for operation within a vacuum, vertical or horizontal centrifugation could be used to safely cast uranium for the production of hollow, cylindrical parts. However, for the production of components of geometries other than hollow tubes, vertical centrifugation could be combined with other casting methods such as semi-permanent mold or investment casting

  10. Energy balance of the global photovoltaic (PV) industry--is the PV industry a net electricity producer?

    Science.gov (United States)

    Dale, Michael; Benson, Sally M

    2013-04-02

    A combination of declining costs and policy measures motivated by greenhouse gas (GHG) emissions reduction and energy security have driven rapid growth in the global installed capacity of solar photovoltaics (PV). This paper develops a number of unique data sets, namely the following: calculation of distribution of global capacity factor for PV deployment; meta-analysis of energy consumption in PV system manufacture and deployment; and documentation of reduction in energetic costs of PV system production. These data are used as input into a new net energy analysis of the global PV industry, as opposed to device level analysis. In addition, the paper introduces a new concept: a model tracking energetic costs of manufacturing and installing PV systems, including balance of system (BOS) components. The model is used to forecast electrical energy requirements to scale up the PV industry and determine the electricity balance of the global PV industry to 2020. Results suggest that the industry was a net consumer of electricity as recently as 2010. However, there is a >50% that in 2012 the PV industry is a net electricity provider and will "pay back" the electrical energy required for its early growth before 2020. Further reducing energetic costs of PV deployment will enable more rapid growth of the PV industry. There is also great potential to increase the capacity factor of PV deployment. These conclusions have a number of implications for R&D and deployment, including the following: monitoring of the energy embodied within PV systems; designing more efficient and durable systems; and deploying PV systems in locations that will achieve high capacity factors.

  11. Effects of precipitation changes on aboveground net primary production and soil respiration in a switchgrass field

    Science.gov (United States)

    This study attempted to test whether switchgrass aboveground net primary production (ANPP) responds to precipitation (PPT) changes in a double asymmetry pattern as framed by Knapp et al. (2016), and whether it is held true for other ecosystem processes such as soil respiration (SR). Data were colle...

  12. Estimating climate change effects on net primary production of rangelands in the United States

    Science.gov (United States)

    Matthew C. Reeves; Adam L. Moreno; Karen E. Bagne; Steven W. Running

    2014-01-01

    The potential effects of climate change on net primary productivity (NPP) of U.S. rangelands were evaluated using estimated climate regimes from the A1B, A2 and B2 global change scenarios imposed on the biogeochemical cycling model, Biome-BGC from 2001 to 2100. Temperature, precipitation, vapor pressure deficit, day length, solar radiation, CO2 enrichment and nitrogen...

  13. Variance-based sensitivity analysis of BIOME-BGC for gross and net primary production

    NARCIS (Netherlands)

    Raj, R.; Hamm, N.A.S.; van der Tol, C.; Stein, A.

    2014-01-01

    Parameterization and calibration of a process-based simulator (PBS) is a major challenge when simulating gross and net primary production (GPP and NPP). The large number of parameters makes the calibration computationally expensive and is complicated by the dependence of several parameters on other

  14. Creating a regional MODIS satellite-driven net primary production dataset for european forests

    NARCIS (Netherlands)

    Neumann, Mathias; Moreno, Adam; Thurnher, Christopher; Mues, Volker; Härkönen, Sanna; Mura, Matteo; Bouriaud, Olivier; Lang, Mait; Cardellini, Giuseppe; Thivolle-Cazat, Alain; Bronisz, Karol; Merganic, Jan; Alberdi, Iciar; Astrup, Rasmus; Mohren, Frits; Zhao, Maosheng; Hasenauer, Hubert

    2016-01-01

    Net primary production (NPP) is an important ecological metric for studying forest ecosystems and their carbon sequestration, for assessing the potential supply of food or timber and quantifying the impacts of climate change on ecosystems. The global MODIS NPP dataset using the MOD17 algorithm

  15. Disturbance and net ecosystem production across three climatically distinct forest landscapes

    Science.gov (United States)

    John L. Campbell; O.J. Sun; B.E. Law

    2004-01-01

    Biometric techniques were used to measure net ecosystem production (NEP) across three climatically distinct forest chronosequences in Oregon. NEP was highly negative immediately following stand-replacing disturbance in all forests and recovered to positive values by 10, 20, and 30 years of age for the mild mesic Coast Range, mesic West Cascades, and semi-arid East...

  16. Improved estimates of net primary productivity from MODIS satellite data at regional and local scales

    Science.gov (United States)

    Yude Pan; Richard Birdsey; John Hom; Kevin McCullough; Kenneth Clark

    2006-01-01

    We compared estimates of net primary production (NPP) from the MODIS satellite with estimates from a forest ecosystem process model (PnET-CN) and forest inventory and analysis (FIA) data for forest types of the mid-Atlantic region of the United States. The regional means were similar for the three methods and for the dominant oak? hickory forests in the region. However...

  17. Green Net Regional Product for the San Luis Basin, Colorado: An Economic Measure of Regional Sustainability

    Science.gov (United States)

    This paper presents the data sources and methodology used to estimate Green Net Regional Product (GNRP), a green accounting approach, for the San Luis Basin (SLB). GNRP is equal to aggregate consumption minus the depreciation of man-made and natural capital. We measure the move...

  18. Relationships between net primary productivity and forest stand age in U.S. forests

    Science.gov (United States)

    Liming He; Jing M. Chen; Yude Pan; Richard Birdsey; Jens. Kattge

    2012-01-01

    Net primary productivity (NPP) is a key flux in the terrestrial ecosystem carbon balance, as it summarizes the autotrophic input into the system. Forest NPP varies predictably with stand age, and quantitative information on the NPP-age relationship for different regions and forest types is therefore fundamentally important for forest carbon cycle modeling. We used four...

  19. Improved assessment of gross and net primary productivity of Canada's landmass

    Science.gov (United States)

    Gonsamo, Alemu; Chen, Jing M.; Price, David T.; Kurz, Werner A.; Liu, Jane; Boisvenue, Céline; Hember, Robbie A.; Wu, Chaoyang; Chang, Kuo-Hsien

    2013-12-01

    assess Canada's gross primary productivity (GPP) and net primary productivity (NPP) using boreal ecosystem productivity simulator (BEPS) at 250 m spatial resolution with improved input parameter and driver fields and phenology and nutrient release parameterization schemes. BEPS is a process-based two-leaf enzyme kinetic terrestrial ecosystem model designed to simulate energy, water, and carbon (C) fluxes using spatial data sets of meteorology, remotely sensed land surface variables, soil properties, and photosynthesis and respiration rate parameters. Two improved key land surface variables, leaf area index (LAI) and land cover type, are derived at 250 m from Moderate Resolution Imaging Spectroradiometer sensor. For diagnostic error assessment, we use nine forest flux tower sites where all measured C flux, meteorology, and ancillary data sets are available. The errors due to input drivers and parameters are then independently corrected for Canada-wide GPP and NPP simulations. The optimized LAI use, for example, reduced the absolute bias in GPP from 20.7% to 1.1% for hourly BEPS simulations. Following the error diagnostics and corrections, daily GPP and NPP are simulated over Canada at 250 m spatial resolution, the highest resolution simulation yet for the country or any other comparable region. Total NPP (GPP) for Canada's land area was 1.27 (2.68) Pg C for 2008, with forests contributing 1.02 (2.2) Pg C. The annual comparisons between measured and simulated GPP show that the mean differences are not statistically significant (p > 0.05, paired t test). The main BEPS simulation error sources are from the driver fields.

  20. Development of net energy ratio and emission factor for quad-generation pathways

    DEFF Research Database (Denmark)

    Rudra, Souman; Rosendahl, Lasse; Kumar, Amit

    2014-01-01

    of this study was to evaluate the energy performance, reduce GHG and acid rain precursor emission, and use of biomass for different outputs based on demand. Finally, a sensitivity analysis and a comparative study ar conducted for expected technological improvements and factors that could increase the energy......, methanol and methane. Circulating fluidized bed gasifier and the gas technology institute (GTI) gasifier technologies are used for this quad-generation process. Two different biomass feedstocks are considered in this study. The net energy ratio for six different pathways having the range of between 1...

  1. UV sensitivity of planktonic net community production in ocean surface waters

    Science.gov (United States)

    Regaudie-de-Gioux, Aurore; Agustí, Susana; Duarte, Carlos M.

    2014-05-01

    The net plankton community metabolism of oceanic surface waters is particularly important as it more directly affects the partial pressure of CO2 in surface waters and thus the air-sea fluxes of CO2. Plankton communities in surface waters are exposed to high irradiance that includes significant ultraviolet blue (UVB, 280-315 nm) radiation. UVB radiation affects both photosynthetic and respiration rates, increase plankton mortality rates, and other metabolic and chemical processes. Here we test the sensitivity of net community production (NCP) to UVB of planktonic communities in surface waters across contrasting regions of the ocean. We observed here that UVB radiation affects net plankton community production at the ocean surface, imposing a shift in NCP by, on average, 50% relative to the values measured when excluding partly UVB. Our results show that under full solar radiation, the metabolic balance shows the prevalence of net heterotrophic community production. The demonstration of an important effect of UVB radiation on NCP in surface waters presented here is of particular relevance in relation to the increased UVB radiation derived from the erosion of the stratospheric ozone layer. Our results encourage design future research to further our understanding of UVB effects on the metabolic balance of plankton communities.

  2. Net emissions of carbon dioxide to the atmosphere when using forest residues for production of heat and electricity

    International Nuclear Information System (INIS)

    Zetterberg, L.; Hansen, O.

    1998-05-01

    This study estimates net emissions of carbon dioxide to the atmosphere from the use of forest residues for production of heat and electricity. In the report, the use of forest residues for energy production is called residue-usage. Our results show that for a turnover period of 80 years, the net emission of CO 2 to the atmosphere is 15.8 kg CO 2 -C/MWh (3.1-31.6 kg CO 2 -C/MWh), which represents 16% of the total carbon content in the wood fuel (3%-32%). Fossil fuel consumption is responsible for 3.1 kg CO 2 -C/MWh of this. Residue-usage may produce indirect emissions or uptake of carbon dioxide, e.g. through changes in production conditions, changes in the turnover of carbon in the humus layer or through a reduction of the amount of forest fires. Due to uncertainties in data it is hard to quantify these indirect effects. In some cases it is hard even to determine their signs. As a consequence of this, we have chosen not to include the indirect effects in our estimates of net emissions from residue-usage. Instead we discuss these effects in a qualitative manner. It may seem surprising that the biogenic part of the residue-usage produces a net emission of carbon dioxide considering that carbon has originated from the atmosphere. The explanation is that the residue-usage systematically leads to earlier emissions than would be the case if the residues were left on the ground. If forest residues are left to decay, in the long run a pool of carbon might be created in the ground. This does not happen with residue-usage 33 refs, 4 figs, 12 tabs

  3. Transformations, Inc.. Partnering To Build Net-Zero Energy Houses in Massachusetts

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, K. [Building Science Corporation, Somerville, MA (United States); Bergey, D. [Building Science Corporation, Somerville, MA (United States); Wytrykowska, H. [Building Science Corporation, Somerville, MA (United States)

    2013-09-01

    Transformations, Inc. is a residential development and building company that has partnered with Building Science Corporation to build new construction net-zero energy houses in Massachusetts under the Building America program. There are three communities that will be constructed through this partnership: Devens Sustainable Housing ("Devens"), The Homes at Easthampton Meadow ("Easthampton") and Phase II of the Coppersmith Way Development ("Townsend"). This report intends to cover all of the single-family new construction homes that have been completed to date. The houses built in these developments are net zero energy homes built in a cold climate. They will contribute to finding answers to specific research questions for homes with high R double stud walls and high efficiency ductless air source heat pump systems ("mini-splits"); allow to explore topics related to the financing of photovoltaic systems and basements vs. slab-on-grade construction; and provide feedback related to the performance of ductless mini-split air source heat pumps.

  4. Determining Mean Annual Energy Production

    DEFF Research Database (Denmark)

    Kofoed, Jens Peter; Folley, Matt

    2016-01-01

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

  5. ENERGY STAR Certified Products - Lighting

    Data.gov (United States)

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

  6. Domestic wastewater treatment as a net energy producer--can this be achieved?

    Science.gov (United States)

    McCarty, Perry L; Bae, Jaeho; Kim, Jeonghwan

    2011-09-01

    In seeking greater sustainability in water resources management, wastewater is now being considered more as a resource than as a waste-a resource for water, for plant nutrients, and for energy. Energy, the primary focus of this article, can be obtained from wastewater's organic as well as from its thermal content. Also, using wastewater's nitrogen and P nutrients for plant fertilization, rather than wasting them, helps offset the high energy cost of producing synthetic fertilizers. Microbial fuel cells offer potential for direct biological conversion of wastewater's organic materials into electricity, although significant improvements are needed for this process to be competitive with anaerobic biological conversion of wastewater organics into biogas, a renewable fuel used in electricity generation. Newer membrane processes coupled with complete anaerobic treatment of wastewater offer the potential for wastewater treatment to become a net generator of energy, rather than the large energy consumer that it is today.

  7. Acoustic calibration for the KM3NeT pre-production module

    Energy Technology Data Exchange (ETDEWEB)

    Enzenhöfer, A., E-mail: alexander.enzenhoefer@physik.uni-erlangen.de [Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen Centre for Astroparticle Physics, Erwin-Rommel-Str. 1, D-91058 Erlangen (Germany)

    2013-10-11

    The proposed large scale Cherenkov neutrino telescope KM3NeT will carry photo-sensors on flexible structures, the detection units. The Mediterranean Sea, where KM3NeT will be installed, constitutes a highly dynamic environment in which the detection units are constantly in motion. Thus it is necessary to monitor the exact sensor positions continuously to achieve the desired resolution for the neutrino telescope. A common way to perform this monitoring is the use of acoustic positioning systems with emitters and receivers based on the piezoelectric effect. The acoustic receivers are attached to detection units whereas the emitters are located at known positions on the sea floor. There are complete commercial systems for this application with sufficient precision. But these systems are limited in the use of their data and inefficient as they were designed to perform only this single task. Several working groups in the KM3NeT consortium are cooperating to custom-design a positioning system for the specific requirements of KM3NeT. Most of the studied solutions hold the possibility to extend the application area from positioning to additional tasks like acoustic particle detection or monitoring of the deep-sea acoustic environment. The KM3NeT Pre-Production Module (PPM) is a test system to verify the correct operation and interoperability of the major involved hardware and software components developed for KM3NeT. In the context of the PPM, alternative designs of acoustic sensors including small piezoelectric elements equipped with preamplifiers inside the same housing as the optical sensors will be tested. These will be described in this article.

  8. Trials for product's data management through RosettaNet using RosettaNet Technical Dictionary (RNTD) and Partner Interface Processes (PIP) 2A10

    Energy Technology Data Exchange (ETDEWEB)

    Shinya, H. [NEC Electronics Corp. (Japan); Katsumi, S. [Sony Corporation Corp. (Japan); Seigo, I. [Toshiba Corp. (Japan); Eita, I. [Fujitsu LTD. (Japan); Hisashi, F.; Mackin, J.W. [RosettaNet (Japan)

    2004-07-01

    We face a major challenge in identifying and tracking the amount of hazardous materials contained in electric and electronic products (EE) in accordance with various changing laws or customers' demands. Hence, the Material Composition Milestone Program (MatComp) was established in RosettaNet (USA) on Jan 2003. Many major electronics companies including NOKIA, Sony, NEC Electronics, Toshiba, Fujitsu, etc. are involved in the MatComp program. In addition, RosettaNet Japan has established an environmental information team to develop dictionaries for chemicals listed in the Joint Industry Guide (draft) which was published September, 2003. The RosettaNet RNTD and PIP 2A10 enable product material composition notification between trading partners. 2A10 allows us to describe the product in a hierarchical structure along with product itself in a method similar to IMDS's requirements. In this paper, we will demonstrate the advantage of using RosettaNet protocol for product data exchange between trading partners. Our goal is to complete a full-automated transaction to a design for environment (DfE). (orig.)

  9. Windows: Win/Win? or when are windows net energy sources?

    Energy Technology Data Exchange (ETDEWEB)

    Moller, S.K.; Delsante, A.E. [Commonwealth Scientific and Industrial Research Organisation (CSIRO), Highett, VIC (Australia). Div. of Building Construction and Engineering

    1994-12-31

    The energy balance of domestic glazing is quantified by using program CHEETAH to examine the effects of orientation, U-value, shading coefficient, overhangs, heating operation (times and temperature), curtain U-value, climate, and building thermal mass. The results are presented graphically, allowing the benefit of increasingly glazing area to be assessed quickly. It is shown that unfavourable combinations of these factors can lead to glazing that is a net loser of energy, even when it is facing north. (author). 1 tab., 17 figs., 6 refs.

  10. Production of bio-energies

    International Nuclear Information System (INIS)

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

    2009-01-01

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

  11. Net modelling of energy mix among European Countries: A proposal for ruling new scenarios

    International Nuclear Information System (INIS)

    Dassisti, M.; Carnimeo, L.

    2012-01-01

    European energy policy pursues the objective of a sustainable, competitive and secure supply of energy. In 2007, the European Commission adopted an energy policy for Europe, which was supported by several documents on different aspects of energy and included an action plan to meet the major energy challenges Europe has to face. A farsighted diversified yearly mix of energies was suggested to countries, aiming at increasing security of supply and efficiency, but a wide and contemporary view of energy interchanges between states was not available. In a previous work of the same authors, energy import/export interchanges between European States were used to develop a geographic overview at one-glance. In this paper, the enhanced Interchange Energy Network (IEN) is investigated from a modelling point of view, as a Small-World Net, by supposing that connections can exist between States with a probability depending also on economic/political relations between countries. -- Highlights: ► Different view of the imports and exports of electric energy flows between European for potential use in ruling exchanges. ► Panel data from 1996 to 2008 as part of a network of exchanges was considered from Eurostat official database. ► The European import/export energy flows modelled as a network with Small-World phenomena, interpreting the evolution over the years. ► Interesting behavioural features as outcome derived, as shown for the case example of the Germany.

  12. Passive designs and renewable energy systems optimization of a net zero energy building in Embrun/France

    Science.gov (United States)

    Harkouss, F.; Biwole, P. H.; Fardoun, F.

    2018-05-01

    Buildings’ optimization is a smart method to inspect the available design choices starting from passive strategies, to energy efficient systems and finally towards the adequate renewable energy system to be implemented. This paper outlines the methodology and the cost-effectiveness potential for optimizing the design of net-zero energy building in a French city; Embrun. The non-dominated sorting genetic algorithm is chosen in order to minimize thermal, electrical demands and life cycle cost while reaching the net zero energy balance; and thus getting the Pareto-front. Elimination and Choice Expressing the Reality decision making method is applied to the Pareto-front so as to obtain one optimal solution. A wide range of energy efficiency measures are investigated, besides solar energy systems are employed to produce required electricity and hot water for domestic purposes. The results indicate that the appropriate selection of the passive parameters is very important and critical in reducing the building energy consumption. The optimum design parameters yield to a decrease of building’s thermal loads and life cycle cost by 32.96% and 14.47% respectively.

  13. Creating a Regional MODIS Satellite-Driven Net Primary Production Dataset for European Forests

    OpenAIRE

    Neumann, Mathias; Moreno, Adam; Thurnher, Christopher; Mues, Volker; Härkönen, Sanna; Mura, Matteo; Bouriaud, Olivier; Lang, Mait; Cardellini, Giuseppe; Thivolle-Cazat, Alain; Bronisz, Karol; Merganic, Jan; Alberdi, Iciar; Astrup, Rasmus; Mohren, Frits

    2016-01-01

    Net primary production (NPP) is an important ecological metric for studying forest ecosystems and their carbon sequestration, for assessing the potential supply of food or timber and quantifying the impacts of climate change on ecosystems. The global MODIS NPP dataset using the MOD17 algorithm provides valuable information for monitoring NPP at 1-km resolution. Since coarse-resolution global climate data are used, the global dataset may contain uncertainties for Europe. We used a 1-km daily g...

  14. Ozone flux over a Norway spruce forest and correlation with net ecosystem production

    Czech Academy of Sciences Publication Activity Database

    Zapletal, M.; Cudlín, Pavel; Chroust, P.; Urban, Otmar; Pokorný, Radek; Edwards, Magda; Czerný, Radek; Janouš, Dalibor; Taufarová, Klára; Večeřa, Zbyněk; Mikuška, Pavel; Paoletti, E.

    2011-01-01

    Roč. 159, č. 5 (2011), s. 1024-1034 ISSN 0269-7491 R&D Projects: GA MŽP SP/1B7/189/07 Institutional research plan: CEZ:AV0Z60870520; CEZ:AV0Z40310501 Keywords : ozone deposition * stomatal conductance * deposition velocity * friction velocity * gradient method * tropospheric ozone * net ecosystem production Subject RIV: EH - Ecology, Behaviour Impact factor: 3.746, year: 2011

  15. Net Zero Fort Carson: Integrating Energy, Water, and Waste Strategies to Lower the Environmental Impact of a Military Base

    Science.gov (United States)

    Military bases resemble small cities and face similar sustainability challenges. As pilot studies in the U.S. Army Net Zero program, 17 locations are moving to 100% renewable energy, zero depletion of water resources, and/or zero waste to landfill by 2020. Some bases target net z...

  16. Gross nitrous oxide production drives net nitrous oxide fluxes across a salt marsh landscape.

    Science.gov (United States)

    Yang, Wendy H; Silver, Whendee L

    2016-06-01

    Sea level rise will change inundation regimes in salt marshes, altering redox dynamics that control nitrification - a potential source of the potent greenhouse gas, nitrous oxide (N2 O) - and denitrification, a major nitrogen (N) loss pathway in coastal ecosystems and both a source and sink of N2 O. Measurements of net N2 O fluxes alone yield little insight into the different effects of redox conditions on N2 O production and consumption. We used in situ measurements of gross N2 O fluxes across a salt marsh elevation gradient to determine how soil N2 O emissions in coastal ecosystems may respond to future sea level rise. Soil redox declined as marsh elevation decreased, with lower soil nitrate and higher ferrous iron in the low marsh compared to the mid and high marshes (P production was highest in the low marsh and lowest in the mid-marsh (P = 0.02), whereas gross N2 O consumption did not differ among marsh zones. Thus, variability in gross N2 O production rates drove the differences in net N2 O flux among marsh zones. Our results suggest that future studies should focus on elucidating controls on the processes producing, rather than consuming, N2 O in salt marshes to improve our predictions of changes in net N2 O fluxes caused by future sea level rise. © 2015 John Wiley & Sons Ltd.

  17. Ozone flux over a Norway spruce forest and correlation with net ecosystem production

    International Nuclear Information System (INIS)

    Zapletal, Milos; Cudlin, Pavel; Chroust, Petr; Urban, Otmar; Pokorny, Radek; Edwards-Jonasova, Magda; Czerny, Radek; Janous, Dalibor; Taufarova, Klara; Vecera, Zbynek; Mikuska, Pavel; Paoletti, Elena

    2011-01-01

    Daily ozone deposition flux to a Norway spruce forest in Czech Republic was measured using the gradient method in July and August 2008. Results were in good agreement with a deposition flux model. The mean daily stomatal uptake of ozone was around 47% of total deposition. Average deposition velocity was 0.39 cm s -1 and 0.36 cm s -1 by the gradient method and the deposition model, respectively. Measured and modelled non-stomatal uptake was around 0.2 cm s -1 . In addition, net ecosystem production (NEP) was measured by using Eddy Covariance and correlations with O 3 concentrations at 15 m a.g.l., total deposition and stomatal uptake were tested. Total deposition and stomatal uptake of ozone significantly decreased NEP, especially by high intensities of solar radiation. - Highlights: → We estimate ozone deposition flux to a Norway spruce forest using the gradient method and model. → The mean stomatal uptake of ozone is approximately 47% of the total deposition. → We measure net ecosystem production (NEP) using Eddy Covariance. → We test whether elevated total deposition and stomatal uptake of O 3 imply a reduction of NEP. → Deposition and stomatal uptake of O 3 decrease NEP, especially by high intensities of solar radiation. - Net ecosystem production of a Norway spruce forest decreases with increasing deposition and stomatal uptake of ozone.

  18. Net energy value of maize ethanol as a response to different climate and soil conditions in the southeastern USA

    Energy Technology Data Exchange (ETDEWEB)

    Persson, Tomas; Garcia y Garcia, Axel; Paz, Joel O.; Hoogenboom, Gerrit [Department of Biological and Agricultural Engineering, 1109 Experiment Street, The University of Georgia, Griffin, GA 30223 (United States); Jones, James W. [Department of Agricultural and Biological Engineering, Frazier Rogers Hall, University of Florida, Gainesville, FL 32611 (United States)

    2009-08-15

    A recent increase in the demand for bio-ethanol has sparked maize production in the USA and other countries across the world. The net energy value (NEV), i.e. the energy output in ethanol and co-products after accounting for energy input requirements in the production chain of ethanol, is a measure of its sustainability. Grain yield of maize, which varies substantially across different climate and soil conditions, greatly impacts the ethanol NEV. The objectives of this study were to determine i) the NEV of ethanol produced from maize grown in four production regions in the southeastern USA and, ii) the specific impact of local soil variability under the same climate conditions within the four regions on the NEV of maize-ethanol. Maize yield was simulated with the Cropping System Model (CSM)-CERES-Maize model for soil and weather conditions, and management practices representing Bulloch, Floyd, Laurens and Mitchell counties, Georgia, USA. The calculation of ethanol NEV took into account the energy inputs and outputs of the entire ethanol production chain, and was based on the crop simulations. There were statistically significant differences in ethanol NEV among the counties, and within counties due to local soil variability. Differences in ethanol NEV among counties were partially due to different transportation distances. Based on the results of this study, it was concluded that maize-ethanol NEV can be increased by accounting for the soil and climate factors in the feedstock production and by locating ethanol-processing facilities in regions with soil and climate conditions that are favorable for ethanol-maize production. (author)

  19. Optimum Temperatures for Net Primary Productivity of Three Tropical Seagrass Species

    Directory of Open Access Journals (Sweden)

    Catherine J. Collier

    2017-08-01

    Full Text Available Rising sea water temperature will play a significant role in responses of the world's seagrass meadows to climate change. In this study, we investigated seasonal and latitudinal variation (spanning more than 1,500 km in seagrass productivity, and the optimum temperatures at which maximum photosynthesis and net productivity (for the leaf and the whole plant occurs, for three seagrass species (Cymodocea serrulata, Halodule uninervis, and Zostera muelleri. To obtain whole plant net production, photosynthesis, and respiration rates of leaves and the root/rhizome complex were measured using oxygen-sensitive optodes in closed incubation chambers at temperatures ranging from 15 to 43°C. The temperature-dependence of photosynthesis and respiration was fitted to empirical models to obtain maximum metabolic rates and thermal optima. The thermal optimum (Topt for gross photosynthesis of Z. muelleri, which is more commonly distributed in sub-tropical to temperate regions, was 31°C. The Topt for photosynthesis of the tropical species, H. uninervis and C. serrulata, was considerably higher (35°C on average. This suggests that seagrass species are adapted to water temperature within their distributional range; however, when comparing among latitudes and seasons, thermal optima within a species showed limited acclimation to ambient water temperature (Topt varied by 1°C in C. serrulata and 2°C in H. uninervis, and the variation did not follow changes in ambient water temperature. The Topt for gross photosynthesis were higher than Topt calculated from plant net productivity, which includes above- and below-ground respiration for Z. muelleri (24°C and H. uninervis (33°C, but remained unchanged at 35°C in C. serrulata. Both estimated plant net productivity and Topt are sensitive to the proportion of below-ground biomass, highlighting the need for consideration of below- to above-ground biomass ratios when applying thermal optima to other meadows. The

  20. Optimum Temperatures for Net Primary Productivity of Three Tropical Seagrass Species.

    Science.gov (United States)

    Collier, Catherine J; Ow, Yan X; Langlois, Lucas; Uthicke, Sven; Johansson, Charlotte L; O'Brien, Katherine R; Hrebien, Victoria; Adams, Matthew P

    2017-01-01

    Rising sea water temperature will play a significant role in responses of the world's seagrass meadows to climate change. In this study, we investigated seasonal and latitudinal variation (spanning more than 1,500 km) in seagrass productivity, and the optimum temperatures at which maximum photosynthesis and net productivity (for the leaf and the whole plant) occurs, for three seagrass species ( Cymodocea serrulata, Halodule uninervis , and Zostera muelleri ). To obtain whole plant net production, photosynthesis, and respiration rates of leaves and the root/rhizome complex were measured using oxygen-sensitive optodes in closed incubation chambers at temperatures ranging from 15 to 43°C. The temperature-dependence of photosynthesis and respiration was fitted to empirical models to obtain maximum metabolic rates and thermal optima. The thermal optimum ( T opt ) for gross photosynthesis of Z. muelleri , which is more commonly distributed in sub-tropical to temperate regions, was 31°C. The T opt for photosynthesis of the tropical species, H. uninervis and C. serrulata , was considerably higher (35°C on average). This suggests that seagrass species are adapted to water temperature within their distributional range; however, when comparing among latitudes and seasons, thermal optima within a species showed limited acclimation to ambient water temperature ( T opt varied by 1°C in C. serrulata and 2°C in H. uninervis , and the variation did not follow changes in ambient water temperature). The T opt for gross photosynthesis were higher than T opt calculated from plant net productivity, which includes above- and below-ground respiration for Z. muelleri (24°C) and H. uninervis ( 33°C), but remained unchanged at 35°C in C. serrulata . Both estimated plant net productivity and T opt are sensitive to the proportion of below-ground biomass, highlighting the need for consideration of below- to above-ground biomass ratios when applying thermal optima to other meadows. The

  1. The supply and demand of net primary production in the Sahel

    International Nuclear Information System (INIS)

    Abdi, A M; Seaquist, J; Tenenbaum, D E; Eklundh, L; Ardö, J

    2014-01-01

    Net primary production (NPP) is the principal source of energy for ecosystems and, by extension, human populations that depend on them. The relationship between the supply and demand of NPP is important for the assessment of socio-ecological vulnerability. We present an analysis of the supply and demand of NPP in the Sahel using NPP estimates from the MODIS sensor and agri-environmental data from FAOSTAT. This synergistic approach allows for a spatially explicit estimation of human impact on ecosystems. We estimated the annual amount of NPP required to derive food, fuel and feed between 2000 and 2010 for 22 countries in sub-Saharan Africa. When comparing annual estimates of supply and demand of NPP, we found that demand increased from 0.44 PgC to 1.13 PgC, representing 19% and 41%, respectively, of available supply due to a 31% increase in the human population between 2000 and 2010. The demand for NPP has been increasing at an annual rate of 2.2% but NPP supply was near-constant with an inter-annual variability of approximately 1.7%. Overall, there were statistically significant (p < 0.05) increases in the NPP of cropland (+6.0%), woodland (+6.1%) and grassland/savanna (+9.4%), and a decrease in the NPP of forests (−0.7%). On the demand side, the largest increase was for food (20.4%) followed by feed (16.7%) and fuel (5.5%). The supply-demand balance of NPP is a potentially important tool from the standpoint of sustainable development, and as an indicator of stresses on the environment stemming from increased consumption of biomass. (letter)

  2. Hydrogen production from solar energy

    Science.gov (United States)

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

    1975-01-01

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

  3. Interannual variability of net ecosystem productivity in forests is explained by carbon flux phenology in autumn

    DEFF Research Database (Denmark)

    Wu, Chaoyang; Chen, Xi Jing; Black, T. Andrew

    2013-01-01

    To investigate the importance of autumn phenology in controlling interannual variability of forest net ecosystem productivity (NEP) and to derive new phenological metrics to explain the interannual variability of NEP. North America and Europe. Flux data from nine deciduous broadleaf forests (DBF......, soil water content and precipitation, were also used to explain the phenological variations. We found that interannual variability of NEP can be largely explained by autumn phenology, i.e. the autumn lag. While variation in neither annual gross primary productivity (GPP) nor in annual ecosystem...

  4. Integration of net zero energy building with smart grid to improve regional electrification ratio towards sustainable development

    Science.gov (United States)

    Latief, Yusuf; Berawi, Mohammed Ali; Supriadi, Leni; Bintang Koesalamwardi, Ario; Petroceany, Jade; Herzanita, Ayu

    2017-12-01

    Indonesia is currently encouraging its physical, social and economy development. Physical development for economic development have to be supported by energy availability. For Indonesia, 90% of electrification ratio is still become an important task that has to be completed by the Government. However, the effort to increase electrification can become an environmental problem if it’s done with BAU scenario. The by-product of electric generation is the GHG, which increasing every year since 2006 from various sectors i.e. industry, housing, commercial, transportation, and energy. Net Zero Energy Building (NZEB) is an energy efficient building which can produce energy independently from clean and renewable sources. The energy that is generated by NZEB can be used for the building itself, and can be exported to the central grid. The integration of NZEB and Smart Grid can solve today’s issue on electrification ratio. Literature study will find benchmarks which can be applied in Indonesia along with possible obstacles in applying this technology.

  5. Small Changes Yield Large Results at NIST's Net-Zero Energy Residential Test Facility.

    Science.gov (United States)

    Fanney, A Hunter; Healy, William; Payne, Vance; Kneifel, Joshua; Ng, Lisa; Dougherty, Brian; Ullah, Tania; Omar, Farhad

    2017-12-01

    The Net-Zero Energy Residential Test Facility (NZERTF) was designed to be approximately 60 % more energy efficient than homes meeting the 2012 International Energy Conservation Code (IECC) requirements. The thermal envelope minimizes heat loss/gain through the use of advanced framing and enhanced insulation. A continuous air/moisture barrier resulted in an air exchange rate of 0.6 air changes per hour at 50 Pa. The home incorporates a vast array of extensively monitored renewable and energy efficient technologies including an air-to-air heat pump system with a dedicated dehumidification cycle; a ducted heat-recovery ventilation system; a whole house dehumidifier; a photovoltaic system; and a solar domestic hot water system. During its first year of operation the NZERTF produced an energy surplus of 1023 kWh. Based on observations during the first year, changes were made to determine if further improvements in energy performance could be obtained. The changes consisted of installing a thermostat that incorporated control logic to minimize the use of auxiliary heat, using a whole house dehumidifier in lieu of the heat pump's dedicated dehumidification cycle, and reducing the ventilation rate to a value that met but did not exceed code requirements. During the second year of operation the NZERTF produced an energy surplus of 2241 kWh. This paper describes the facility, compares the performance data for the two years, and quantifies the energy impact of the weather conditions and operational changes.

  6. Estimation of absorbed photosynthetically active radiation and vegetation net production efficiency using satellite data

    International Nuclear Information System (INIS)

    Hanan, N.P.; Prince, S.D.; Begue, A.

    1995-01-01

    The amount of photosynthetically active radiation (PAR) absorbed by green vegetation is an important determinant of photosynthesis and growth. Methods for the estimation of fractional absorption of PAR (iff PAR ) for areas greater than 1 km 2 using satellite data are discussed, and are applied to sites in the Sahel that have a sparse herb layer and tree cover of less than 5%. Using harvest measurements of seasonal net production, net production efficiencies are calculated. Variation in estimates of seasonal PAR absorption (APAR) caused by the atmospheric correction method and relationship between surface reflectances and iff PAR is considered. The use of maximum value composites of satellite NDVI to reduce the effect of the atmosphere is shown to produce inaccurate APAR estimates. In this data set, however, atmospheric correction using average optical depths was found to give good approximations of the fully corrected data. A simulation of canopy radiative transfer using the SAIL model was used to derive a relationship between canopy NDVI and iff PAR . Seasonal APAR estimates assuming a 1:1 relationship between iff PAR and NDVI overestimated the SAIL modeled results by up to 260%. The use of a modified 1:1 relationship, where iff PAR was assumed to be linearly related to NDVI scaled between minimum (soil) and maximum (infinite canopy) values, underestimated the SAIL modeled results by up to 35%. Estimated net production efficiencies (ϵ n , dry matter per unit APAR) fell in the range 0.12–1.61 g MJ −1 for above ground production, and in the range 0.16–1.88 g MJ −1 for total production. Sites with lower rainfall had reduced efficiencies, probably caused by physiological constraints on photosynthesis during dry conditions. (author)

  7. Sustainable Skyscrapers: Designing the Net Zero Energy Building of the Future

    Science.gov (United States)

    Kothari, S.; Bartsch, A.

    2016-12-01

    Cities of the future will need to increase population density in order to keep up with the rising populations in the limited available land area. In order to provide sufficient power as the population grows, cities must become more energy efficient. Fossil fuels and grid energy will continue to become more expensive as nonrenewable resources deplete. The obvious solution to increase population density while decreasing the reliance on fossil fuels is to build taller skyscrapers that are energy neutral, i.e. self-sustaining. However, current skyscrapers are not energy efficient, and therefore cannot provide a sustainable solution to the problem of increasing population density in the face of depleting energy resources. The design of a net zero energy building that includes both residential and commercial space is presented. Alternative energy systems such as wind turbines, photovoltaic cells, and a waste-to-fuel conversion plant have been incorporated into the design of a 50 story skyscraper that is not reliant on fossil fuels and has a payback time of about six years. Although the current building was designed to be located in San Francisco, simple modifications to the design would allow this building to fit the needs of any city around the world.

  8. Fusion Energy for Hydrogen Production

    Energy Technology Data Exchange (ETDEWEB)

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

    1978-09-01

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

  9. Selecting HVAC Systems to Achieve Comfortable and Cost-effective Residential Net-Zero Energy Buildings.

    Science.gov (United States)

    Wu, Wei; Skye, Harrison M; Domanski, Piotr A

    2018-02-15

    HVAC is responsible for the largest share of energy use in residential buildings and plays an important role in broader implementation of net-zero energy building (NZEB). This study investigated the energy, comfort and economic performance of commercially-available HVAC technologies for a residential NZEB. An experimentally-validated model was used to evaluate ventilation, dehumidification, and heat pump options for the NZEB in the mixed-humid climate zone. Ventilation options were compared to mechanical ventilation without recovery; a heat recovery ventilator (HRV) and energy recovery ventilator (ERV) respectively reduced the HVAC energy by 13.5 % and 17.4 % and reduced the building energy by 7.5 % and 9.7 %. There was no significant difference in thermal comfort between the ventilation options. Dehumidification options were compared to an air-source heat pump (ASHP) with a separate dehumidifier; the ASHP with dedicated dehumidification reduced the HVAC energy by 7.3 % and the building energy by 3.9 %. The ASHP-only option (without dedicated dehumidification) reduced the initial investment but provided the worst comfort due to high humidity levels. Finally, ground-source heat pump (GSHP) alternatives were compared to the ASHP; the GSHP with two and three boreholes reduced the HVAC energy by 26.0 % and 29.2 % and the building energy by 13.1 % and 14.7 %. The economics of each HVAC configuration was analyzed using installation cost data and two electricity price structures. The GSHPs with the ERV and dedicated dehumidification provided the highest energy savings and good comfort, but were the most expensive. The ASHP with dedicated dehumidification and the ERV (or HRV) provided reasonable payback periods.

  10. Assessing the impact of urbanization on regional net primary productivity in Jiangyin County, China.

    Science.gov (United States)

    Xu, C; Liu, M; An, S; Chen, J M; Yan, P

    2007-11-01

    Urbanization is one of the most important aspects of global change. The process of urbanization has a significant impact on the terrestrial ecosystem carbon cycle. The Yangtze Delta region has one of the highest rates of urbanization in China. In this study, carried out in Jiangyin County as a representative region within the Yangtze Delta, land use and land cover changes were estimated using Landsat TM and ETM+ imagery. With these satellite data and the BEPS process model (Boreal Ecosystem Productivity Simulator), the impacts of urbanization on regional net primary productivity (NPP) and annual net primary production were assessed for 1991 and 2002. Landsat-based land cover maps in 1991 and 2002 showed that urban development encroached large areas of cropland and forest. Expansion of residential areas and reduction of vegetated areas were the major forms of land transformation in Jiangyin County during this period. Mean NPP of the total area decreased from 818 to 699 gCm(-2)yr(-1) during the period of 1991 to 2002. NPP of cropland was only reduced by 2.7% while forest NPP was reduced by 9.3%. Regional annual primary production decreased from 808 GgC in 1991 to 691 GgC in 2002, a reduction of 14.5%. Land cover changes reduced regional NPP directly, and the increasing intensity and frequency of human-induced disturbance in the urbanized areas could be the main reason for the decrease in forest NPP.

  11. Control of Greenhouse Gas Emissions by Optimal DER Technology Investment and Energy Management in Zero-Net-Energy Buildings

    International Nuclear Information System (INIS)

    Stadler, Michael; Siddiqui, Afzal; Marnay, Chris; Aki, Hirohisa; Lai, Judy

    2009-01-01

    The U.S. Department of Energy has launched the commercial building initiative (CBI) in pursuit of its research goal of achieving zero-net-energy commercial buildings (ZNEB), i.e. ones that produce as much energy as they use. Its objective is to make these buildings marketable by 2025 such that they minimize their energy use through cutting-edge, energy-efficiency technologies and meet their remaining energy needs through on-site renewable energy generation. This paper examines how such buildings may be implemented within the context of a cost- or CO2-minimizing microgrid that is able to adopt and operate various technologies: photovoltaic modules (PV) and other on-site generation, heat exchangers, solar thermal collectors, absorption chillers, and passive/demand-response technologies. A mixed-integer linear program (MILP) that has a multi-criteria objective function is used. The objective is minimization of a weighted average of the building's annual energy costs and CO2 emissions. The MILP's constraints ensure energy balance and capacity limits. In addition, constraining the building's energy consumed to equal its energy exports enables us to explore how energy sales and demand-response measures may enable compliance with the ZNEB objective. Using a commercial test site in northernCalifornia with existing tariff rates and technology data, we find that a ZNEB requires ample PV capacity installed to ensure electricity sales during the day. This is complemented by investment in energy-efficient combined heat and power (CHP) equipment, while occasional demand response shaves energy consumption. A large amount of storage is also adopted, which may be impractical. Nevertheless, it shows the nature of the solutions and costs necessary to achieve a ZNEB. Additionally, the ZNEB approach does not necessary lead to zero-carbon (ZC) buildings as is frequently argued. We also show a multi-objective frontier for the CA example, whichallows us to estimate the needed technologies

  12. Transformations, Inc.: Partnering to Build Net-Zero Energy Houses in Massachusetts

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, K. [Building Science Corporation, Somerville, MA (United States); Bergey, D. [Building Science Corporation, Somerville, MA (United States); Wytrykowska, H. [Building Science Corporation, Somerville, MA (United States)

    2013-09-01

    Transformations, Inc. is a residential development and building company that has partnered with Building Science Corporation to build new construction net-zero energy houses in Massachusetts under the Building America program. There are three communities that will be constructed through this partnership: Devens Sustainable Housing ('Devens'), The Homes at Easthampton Meadow ('Easthampton') andPhase II of the Coppersmith Way Development ('Townsend'). This report intends to cover all of the single-family new construction homes that have been completed to date. The houses built in these developments are net zero energy homes built in a cold climate. They will contribute to finding answers to specific research questions for homes with high R double stud walls and high efficiency ductlessair source heat pump systems ('mini-splits'); allow to explore topics related to the financing of photovoltaic systems and basements vs. slab-on-grade construction; and provide feedback related to the performance of ductless mini-split air source heat pumps.

  13. Energy Consumption and Saving Analysis for Laser Engineered Net Shaping of Metal Powders

    Directory of Open Access Journals (Sweden)

    Zhichao Liu

    2016-09-01

    Full Text Available With the increasing awareness of environmental protection and sustainable manufacturing, the environmental impact of laser additive manufacturing (LAM technology has been attracting more and more attention. Aiming to quantitatively analyze the energy consumption and extract possible ways to save energy during the LAM process, this investigation studies the effects of input variables including laser power, scanning speed, and powder feed rate on the overall energy consumption during the laser deposition processes. Considering microhardness as a standard quality, the energy consumption of unit deposition volume (ECUDV, in J/mm3 is proposed as a measure for the average applied energy of the fabricated metal part. The potential energy-saving benefits of the ultrasonic vibration–assisted laser engineering net shaping (LENS process are also examined in this paper. The experimental results suggest that the theoretical and actual values of the energy consumption present different trends along with the same input variables. It is possible to reduce the energy consumption and, at the same time, maintain a good part quality and the optimal combination of the parameters referring to Inconel 718 as a material is laser power of 300 W, scanning speed of 8.47 mm/s and powder feed rate of 4 rpm. When the geometry shaping and microhardness are selected as evaluating criterions, American Iron and Steel Institute (AISI 4140 powder will cause the largest energy consumption per unit volume. The ultrasonic vibration–assisted LENS process cannot only improve the clad quality, but can also decrease the energy consumption to a considerable extent.

  14. THE RENEWABLE ENERGY PRODUCTION-ECONOMIC DEVELOPMENT NEXUS

    Directory of Open Access Journals (Sweden)

    Gorkemli Kazar

    2014-04-01

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

  15. New User Interface Architecture for NetWiser Product with AngularJS

    OpenAIRE

    Johansson, Janne

    2015-01-01

    The topic of the thesis was to develop a new user interface for a product called NetWiser. The need for a new user interface originated from the problems experienced with the technology of the old user interface. A decision was made to replace the old Java applets based user interface with a new JavaScript based user interface. In practice, the technology switch meant a complete redevelopment of the user interface application component. A complete redesign of the user interface layout was exc...

  16. Conformal Haag-Kastler nets, pointlike localized fields and the existence of operator product expansions

    International Nuclear Information System (INIS)

    Fredenhagen, K.; Joerss, M.

    1994-10-01

    Starting from a chiral conformal Haag-Kastler net on 2 dimensional Minkowski space we construct associated pointlike localized fields. This amounts to a proof of the existence of operator product expansions. We derive the result in two ways. One is based on the geometrical identification of the modular structure, the other depends on a ''conformal cluster theorem'' of the conformal two-point-functions in algebraic quantum field theory. The existence of the fields then implies important structural properties of the theory, as PCT-invariance, the Bisognano-Wichmann identification of modular operators, Haag duality and additivity. (orig.)

  17. Worldwide estimates and bibliography of net primary productivity derived from pre-1982 publications

    Energy Technology Data Exchange (ETDEWEB)

    Esser, G. [Justus-Liebig-Univ., Giessen (Germany). Inst. for Plant Ecology; Lieth, H.F.H. [Univ. of Osnabrueck (Germany). Systems Research Group; Scurlock, J.M.O.; Olson, R.J. [Oak Ridge National Lab., TN (United States)

    1997-10-01

    An extensive compilation of more than 700 field estimates of net primary productivity of natural and agricultural ecosystems worldwide was synthesized in Germany in the 1970s and early 1980s. Although the Osnabrueck data set has not been updated since the 1980s, it represents a wealth of information for use in model development and validation. This report documents the development of this data set, its contents, and its recent availability on the Internet from the Oak Ridge National Laboratory Distributed Active Archive Center for Biogeochemical Dynamics. Caution is advised in using these data, which necessarily include assumptions and conversions that may not be universally applicable to all sites.

  18. Results of dose calculations for NET accidental and normal operation releases of tritium and activation products

    International Nuclear Information System (INIS)

    Raskob, W.; Hasemann, I.

    1992-08-01

    This report documents conditions, data and results of dose calculations for accidental and normal operation releases of tritium and activation products, performed within the NET subtask SEP2.2 ('NET-Benchmark') of the European Fusion Technology Programme. For accidental releases, the computer codes UFOTRI and COSYMA for assessing the radiological consequences, have been applied for both deterministic and probabilistic calculations. The influence on dose estimates of different release times (2 minutes / 1 hour), two release heights (10 m / 150 m), two chemical forms of tritium (HT/HTO), and two different model approaches for the deposition velocity of HTO on soil was investigated. The dose calculations for normal operation effluents were performed using the tritium model of the German regulatory guidelines, parts of the advanced dose assessment model NORMTRI still under development, and the statistical atmospheric dispersion model ISOLA. Accidental and normal operation source terms were defined as follows: 10g (3.7 10 15 Bq) for accidental tritium releases, 10 Ci/day (3.7 10 11 Bq/day) for tritium releases during normal operation and unit releases of 10 9 Bq for accidental releases of activation products and fission products. (orig./HP) [de

  19. Net community production from autonomous oxygen observations in the Sargasso Sea

    Science.gov (United States)

    Feen, M.; Estapa, M. L.

    2016-02-01

    Optical sensors on autonomous floats provide high-resolution profiles of oxygen concentration over time. Improved spatiotemporal resolution in our measurements of oxygen will allow for better estimates of net community production and a greater understanding of the biological pump. Two autonomous profiling floats (NAVIS BGCi, Sea-Bird) equipped with SBE-63 optodes to measure dissolved oxygen were deployed in the Sargasso Sea on a series of five Bermuda Atlantic Time-series Study (BATS) cruises from July 2013 to April 2014. In situ calibration of the oxygen sensors to Winkler titration bottle samples at BATS did not show systematic drift in the oxygen sensors over time. Calibrations were applied to determine oxygen concentrations in profiles collected in the Sargasso Sea at 1.5 to 2.5 day intervals over a year. Oxygen concentrations were used to quantify sub-mixed layer net community production. Changes in production rates from this study were compared with upper water column biology and particle flux measurements obtained independently from optical sensors on the profiling floats, allowing us to examine processes controlling carbon export into the deep ocean.

  20. Decreasing Net Primary Productivity in Response to Urbanization in Liaoning Province, China

    Directory of Open Access Journals (Sweden)

    Tan Chen

    2017-01-01

    Full Text Available Regional ecosystems have been greatly affected by the rapid expansion of urban areas. In order to explore the impact of land use change on net primary productivity (NPP in rapidly developing cities during the current urbanization process, we quantified land use change in Liaoning province between 2000 and 2010 using net primary productivity as an indicator of ecosystem productivity and health. The Carnegie–Ames–Stanford Approach model was used to estimate NPP by region and land use. We used a unit circle-based evaluation model to quantify local urbanization effects on NPP around eight representative cities. The dominant land use types were farmland, woodland and urban, with urban rapidly replacing farmland. Mean annual NPP and total NPP decreased faster from 2005 to 2010 than from 2000 to 2005, reflecting increasing urbanization rates. The eastern, primarily woodland part of Liaoning province had the greatest reduction in NPP, while the western part, which was primarily farmland and grassland, had the lowest reduction.

  1. Hydrogen Production from Nuclear Energy

    Science.gov (United States)

    Walters, Leon; Wade, Dave

    2003-07-01

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

  2. Photosynthetic Energy Storage for the Built Environment: Modeling Energy Generation and Storage for Net-Zero Analysis

    Science.gov (United States)

    Lichter-Marck, Eli Morris

    There is a growing need to address the energy demand of the building sector with non-polluting, renewable energy sources. The Net Zero Energy Building (NZEB) mandate seeks to reduce the impact of building sector energy consumption by encouraging on-site energy generation as a way to offset building loads. However, current approaches to designing on-site generation fail to adequately match the fluctuating load schedules of the built environment. As a result, buildings produce highly variable and often-unpredictable energy import/export patterns that create stress on energy grids and increase building dependence on primary energy resources. This research investigates the potential of integrating emerging photo-electrochemical (PEC) technologies into on-site generation systems as a way to enable buildings to take a more active role in collecting, storing and deploying energy resources according to their own demand schedules. These artificially photosynthetic systems have the potential to significantly reduce variability in hour-to-hour and day-to-day building loads by introducing high-capacity solar-hydrogen into the built environment context. The Building Integrated Artificial Photosynthesis (BIAP) simulation framework presented here tests the impact of hydrogen based energy storage on NZEB performance metrics with the goal of developing a methodology that makes on-site energy generation more effective at alleviating excessive energy consumption in the building sector. In addition, as a design performance framework, the BIAP framework helps guide how material selection and scale up of device design might tie photo-electrochemical devices into parallel building systems to take full advantage of the potential outputs of photosynthetic building systems.

  3. Disturbance, complexity, and succession of net ecosystem production in North America’s temperate deciduous forests

    Energy Technology Data Exchange (ETDEWEB)

    Gough, Christopher; Curtis, Peter; Hardiman, Brady; Scheuermann, Cynthia; Bond-Lamberty, Benjamin

    2016-06-29

    Century-old forests in the U.S. upper Midwest and Northeast power much of North Amer- ica’s terrestrial carbon (C) sink, but these forests’ production and C sequestration capacity are expected to soon decline as fast-growing early successional species die and are replaced by slower growing late successional species. But will this really happen? Here we marshal empirical data and ecological theory to argue that substantial declines in net ecosystem production (NEP) owing to reduced forest growth, or net primary production (NPP), are not imminent in regrown temperate deciduous forests over the next several decades. Forest age and production data for temperate deciduous forests, synthesized from published literature, suggest slight declines in NEP and increasing or stable NPP during middle successional stages. We revisit long-held hypotheses by EP Odum and others that suggest low-severity, high-frequency disturbances occurring in the region’s aging forests will, against intuition, maintain NEP at higher-than- expected rates by increasing ecosystem complexity, sustaining or enhancing NPP to a level that largely o sets rising C losses as heterotrophic respiration increases. This theoretical model is also supported by biological evidence and observations from the Forest Accelerated Succession Experiment in Michigan, USA. Ecosystems that experience high-severity disturbances that simplify ecosystem complexity can exhibit substantial declines in production during middle stages of succession. However, observations from these ecosystems have exerted a disproportionate in uence on assumptions regarding the trajectory and magnitude of age-related declines in forest production. We conclude that there is a wide ecological space for forests to maintain NPP and, in doing so, lessens the declines in NEP, with signi cant implications for the future of the North American carbon sink. Our intellectual frameworks for understanding forest C cycle dynamics and resilience need to

  4. Mesozooplankton production, grazing and respiration in the Bay of Bengal: Implications for net heterotrophy

    Science.gov (United States)

    Fernandes, Veronica; Ramaiah, N.

    2016-03-01

    Mesozooplankton samples were collected from the mixed layer along a central (along 88°E) and a western transect in the Bay of Bengal during four seasons covered between 2001 and 2006 in order to investigate spatio-temporal variability in their biomass. At these stations, grazing and respiration rates were measured from live zooplankton hauled in from the surface during December 2005. Akin to the mesozooplankton "paradox" in the central and eastern Arabian Sea, biomass in the mixed layer was more or less invariant in the central and western Bay of Bengal, even as the chl a showed marginal temporal variation. By empirical equation, the mesozooplankton production rate calculated to be 70-246 mg C m- 2 d- 1 is on par with the Arabian Sea. Contrary to the conventional belief, mesozooplankton grazing impact was up to 83% on primary production (PP). Low PP coupled with very high zooplankton production (70% of PP) along with abundant bacterial production (50% of the PP; Ramaiah et al., 2009) is likely to render the Bay of Bengal net heterotrophic, especially during the spring intermonsoon. Greater estimates of fecal pellet-carbon egestion by mesozooplankton compared to the average particulate organic carbon flux in sediment traps, implies that much of the matter is recycled by heterotrophic communities in the mixed layer facilitating nutrient regeneration for phytoplankton growth. We also calculated that over a third of the primary production is channelized for basin-wide zooplankton respiration that accounts for 52 Mt C annually. In the current scenario of global warming, if low (primary) productive warm pools like the Bay of Bengal continue to be net heterotrophic, negative implications like enhanced emission of CO2 to the atmosphere, increased particulate flux to the deeper waters and greater utilization of dissolved oxygen resulting in expansion of the existing oxygen minimum zone are imminent.

  5. Energy Behavior Change and Army Net Zero Energy; Gaps in the Army’s Approach to Changing Energy Behavior

    Science.gov (United States)

    2014-06-13

    efficient technologies, the next step is investigating energy recovery and cogeneration for economic feasibility. Lastly, meet remaining energy loads...by energy efficiency, then energy recovery and cogeneration technologies and last filling the remaining energy requirement with renewable energy ...access to sufficient energy supplies, and reduced adverse impacts on the environment (Army Senior Energy Council 2009, 4). In order to meet these goals

  6. Optimal Technology Investment and Operation in Zero-Net-Energy Buildings with Demand Response

    International Nuclear Information System (INIS)

    Stadler, Michael; Siddiqui, Afzal; Marnay, Chris; Hirohisa, Aki; Lai, Judy

    2009-01-01

    The US Department of Energy has launched the Zero-Net-Energy (ZNE) Commercial Building Initiative (CBI) in order to develop commercial buildings that produce as much energy as they use. Its objective is to make these buildings marketable by 2025 such that they minimize their energy use through cutting-edge energy-efficient technologies and meet their remaining energy needs through on-site renewable energy generation. We examine how such buildings may be implemented within the context of a cost- or carbon-minimizing microgrid that is able to adopt and operate various technologies, such as photovoltaic (PV) on-site generation, heat exchangers, solar thermal collectors, absorption chillers, and passive/demand-response technologies. We use a mixed-integer linear program (MILP) that has a multi-criteria objective function: the minimization of a weighted average of the building's annual energy costs and carbon/CO2 emissions. The MILP's constraints ensure energy balance and capacity limits. In addition, constraining the building's energy consumed to equal its energy exports enables us to explore how energy sales and demand-response measures may enable compliance with the CBI. Using a nursing home in northern California and New York with existing tariff rates and technology data, we find that a ZNE building requires ample PV capacity installed to ensure electricity sales during the day. This is complemented by investment in energy-efficient combined heat and power equipment, while occasional demand response shaves energy consumption. A large amount of storage is also adopted, which may be impractical. Nevertheless, it shows the nature of the solutions and costs necessary to achieve ZNE. For comparison, we analyze a nursing home facility in New York to examine the effects of a flatter tariff structure and different load profiles. It has trouble reaching ZNE status and its load reductions as well as efficiency measures need to be more effective than those in the CA case

  7. Biomass in Switzerland. Energy production

    International Nuclear Information System (INIS)

    Guggisberg, B.

    2006-01-01

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

  8. Net Biome Productivity of different land use at the sites of the Tharandt cluster

    Science.gov (United States)

    Grünwald, T.; Prescher, A.-K.; Bernhofer, Ch.

    2009-04-01

    Within the Tharandt cluster there are 5 flux monitoring sites including 3 CARBOEUROPE main sites. The CARBOEUROPE sites cover typical land use of the region (spruce [monitored since 1996], grassland [since 2003], cropland [since 2004]). For all sites estimates of the Net Biome Productivity (NBP) and its uncertainty have been derived using Net Ecosystem Productivity (NEP) based on the EC measurements and C exports and imports on an annual basis. The crop site is a small C sink (NEP of 30-110gCm-2a-1) only. The annual NEP values are dependent on the cultivated crop species (winter or summer crop). Including C export (harvest) and C import (manure spreading) lead to a considerable C source of 270-540gCm-2a-1. Organic fertilisation (C import) has a strong impact on NBP values expressed in a reduced annual net carbon source. Also, the largest interannual differences of NBP values are found at this site - mainly induced by the existence and the amount of a carbon import due to organic fertilisation. Management practices affect the NBP in a sensitive way at this crop site. Each crop shows a higher C export due to harvest than the annual NEP. To validate the calculated C equivalent using harvested grain biomass modelled NPP values are available. Uncertainty ranges of C export, C import and NBP as well as the grassland and spruce NBP (for comparison) are also stated. In general, land use and management strongly affect the annual NBP of non-forested ecosystems especially. So, this is the second main driver of the C budget besides the interannual variability in meteorological conditions and water availability with its influence on NEP, GPP and TER.

  9. Energy efficiency and econometric analysis of broiler production farms

    International Nuclear Information System (INIS)

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

    2011-01-01

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

  10. Estimating crop net primary production using inventory data and MODIS-derived parameters

    Energy Technology Data Exchange (ETDEWEB)

    Bandaru, Varaprasad; West, Tristram O.; Ricciuto, Daniel M.; Izaurralde, Roberto C.

    2013-06-03

    National estimates of spatially-resolved cropland net primary production (NPP) are needed for diagnostic and prognostic modeling of carbon sources, sinks, and net carbon flux. Cropland NPP estimates that correspond with existing cropland cover maps are needed to drive biogeochemical models at the local scale and over national and continental extents. Existing satellite-based NPP products tend to underestimate NPP on croplands. A new Agricultural Inventory-based Light Use Efficiency (AgI-LUE) framework was developed to estimate individual crop biophysical parameters for use in estimating crop-specific NPP. The method is documented here and evaluated for corn and soybean crops in Iowa and Illinois in years 2006 and 2007. The method includes a crop-specific enhanced vegetation index (EVI) from the Moderate Resolution Imaging Spectroradiometer (MODIS), shortwave radiation data estimated using Mountain Climate Simulator (MTCLIM) algorithm and crop-specific LUE per county. The combined aforementioned variables were used to generate spatially-resolved, crop-specific NPP that correspond to the Cropland Data Layer (CDL) land cover product. The modeling framework represented well the gradient of NPP across Iowa and Illinois, and also well represented the difference in NPP between years 2006 and 2007. Average corn and soybean NPP from AgI-LUE was 980 g C m-2 yr-1 and 420 g C m-2 yr-1, respectively. This was 2.4 and 1.1 times higher, respectively, for corn and soybean compared to the MOD17A3 NPP product. Estimated gross primary productivity (GPP) derived from AgI-LUE were in close agreement with eddy flux tower estimates. The combination of new inputs and improved datasets enabled the development of spatially explicit and reliable NPP estimates for individual crops over large regional extents.

  11. Targeting International Food Aid Programmes: The Case of Productive Safety Net Programme in Tigray, Ethiopia

    Directory of Open Access Journals (Sweden)

    Hossein Azadi

    2017-09-01

    Full Text Available Ethiopia has experienced more than five major droughts in the past three decades, leading to high dependency on international food aids. Nevertheless, studies indicate that asset depletion has not been prevented; neither did food insecurity diminish. Since 2004/5, the Productive Safety Net Programme (PSNP has been implemented to improve food security in Tigray, Northern Ethiopia. Critics point out that the implementation of food aid programmes can have negative impacts as well as positive outcomes for local communities. Accordingly, this survey study aimed to analyse the distribution and allocation of food aids in the Productive Safety Net Programme (PSNP in Tigray. Results of 479 interviews revealed that targeting different households in the PSNP has been considerably linked to socio-demographic attributes among which age and size of family were decisive factors to receive food aids. Furthermore, older households with smaller family size received more direct support. Inequality between genders was another major finding of this study. When combined with the marital status, there was also a big difference in the percentage of married or unmarried women receiving food aids. These findings could provide fundamental information for policy intervention to correct food security programmes at household level and reduce hunger. Given that, socio-demographic factors can help to identify particular and usually different requirements, vulnerabilities and coping strategies of the members of the food aid programme, so that they can be much more addressed when an emergency happens.

  12. "Legal highs" on the net-Evaluation of UK-based Websites, products and product information.

    Science.gov (United States)

    Schmidt, Martin M; Sharma, Akhilesh; Schifano, Fabrizio; Feinmann, Charlotte

    2011-03-20

    A vast array of substances are marketed as "legal highs" in the UK. These products are mainly marketed online and are packaged and produced to mimic illicit drugs. Little is known about the full range of products available at present and no studies have evaluated the product information provided to consumers. AIMS & HYPOTHESIS: To describe the available legal high products marketed by UK-based Internet retailers and evaluate the product information provided to consumers. Websites were identified using the terms "buy legal highs+UK" and two search engines. The first 100 hits and a random sample of 5% of the remaining results were screened. Websites based in the UK were included and all products were entered on a database. Information on product name, list price, claimed effects, side effects, contraindications and interactions was extracted. A descriptive analysis was conducted using SPSS v14. 115 Websites met the inclusion criteria but due to duplicate listings this was reduced to 39 unique Websites. 1308 products were found and evaluated. The average product price was 9.69 British pounds. Products took the form of pills (46.6%), smoking material (29.7%) and single plant material/extract (18.1%). Most products claimed to be stimulants (41.7%), sedatives (32.3%), or hallucinogens (12.9%). 40.1% of products failed to list ingredients, 91.9% failed to list side effects, 81.9% failed to list contraindications and 86.3% failed to list drug interactions. Top 5 products (with active ingredients in brackets) by frequency were Salvia divinorum (Salivinorin A), Kratom (Mitragynine), Hawaiian Baby Woodrose Seeds (Lysergic Acid Amide), Fly Agaric (Ibotenic Acid, Muscimol) and Genie (JWH018, CP47497). Products marketed as "legal highs" are easily available from UK-based Internet retailers and are reasonably affordable. Safety information provided to consumers is poor. Uninformed users risk serious adverse effects. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  13. Energy use pattern analyses of greenhouse vegetable production

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-07-15

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

  14. Life cycle assessment and sustainable engineering in the context of near net shape grown components: striving towards a sustainable way of future production.

    Science.gov (United States)

    Kämpfer, Christoph; Seiler, Thomas-Benjamin; Beger, Anna-Lena; Jacobs, Georg; Löwer, Manuel; Moser, Franziska; Reimer, Julia; Trautz, Martin; Usadel, Björn; Wormit, Alexandra; Hollert, Henner

    2017-01-01

    Technical product harvesting (TEPHA) is a newly developing interdisciplinary approach in which bio-based production is investigated from a technical and ecological perspective. Society's demand for ecologically produced and sustainably operable goods is a key driver for the substitution of conventional materials like metals or plastics through bio-based alternatives. Technical product harvesting of near net shape grown components describes the use of suitable biomass for the production of technical products through influencing the natural shape of plants during their growth period. The use of natural materials may show positive effects on the amount of non-renewable resource consumption. This also increases the product recyclability at the end of its life cycle. Furthermore, through the near net shape growth of biomass, production steps can be reduced. As a consequence such approaches may save energy and the needed resources like crude oil, coal or gas. The derived near net shape grown components are not only considered beneficial from an environmental point of view. They can also have mechanical advantages through an intrinsic topology optimization in contrast to common natural materials, which are influenced in their shape after harvesting. In order to prove these benefits a comprehensive, interdisciplinary scientific strategy is needed. Here, both mechanical investigations and life cycle assessment as a method of environmental evaluation are used.

  15. Observation and simulation of net primary productivity in Qilian Mountain, western China.

    Science.gov (United States)

    Zhou, Y; Zhu, Q; Chen, J M; Wang, Y Q; Liu, J; Sun, R; Tang, S

    2007-11-01

    We modeled net primary productivity (NPP) at high spatial resolution using an advanced spaceborne thermal emission and reflection radiometer (ASTER) image of a Qilian Mountain study area using the boreal ecosystem productivity simulator (BEPS). Two key driving variables of the model, leaf area index (LAI) and land cover type, were derived from ASTER and moderate resolution imaging spectroradiometer (MODIS) data. Other spatially explicit inputs included daily meteorological data (radiation, precipitation, temperature, humidity), available soil water holding capacity (AWC), and forest biomass. NPP was estimated for coniferous forests and other land cover types in the study area. The result showed that NPP of coniferous forests in the study area was about 4.4 tCha(-1)y(-1). The correlation coefficient between the modeled NPP and ground measurements was 0.84, with a mean relative error of about 13.9%.

  16. Drought-induced reduction in global terrestrial net primary production from 2000 through 2009.

    Science.gov (United States)

    Zhao, Maosheng; Running, Steven W

    2010-08-20

    Terrestrial net primary production (NPP) quantifies the amount of atmospheric carbon fixed by plants and accumulated as biomass. Previous studies have shown that climate constraints were relaxing with increasing temperature and solar radiation, allowing an upward trend in NPP from 1982 through 1999. The past decade (2000 to 2009) has been the warmest since instrumental measurements began, which could imply continued increases in NPP; however, our estimates suggest a reduction in the global NPP of 0.55 petagrams of carbon. Large-scale droughts have reduced regional NPP, and a drying trend in the Southern Hemisphere has decreased NPP in that area, counteracting the increased NPP over the Northern Hemisphere. A continued decline in NPP would not only weaken the terrestrial carbon sink, but it would also intensify future competition between food demand and proposed biofuel production.

  17. Productive vegetation: relationships between net primary productivity, vegetation types and climate change in the Wet Tropics bioregion

    International Nuclear Information System (INIS)

    Ramirez, Vanessa Valdez; Williams, Stephen E.; VanDerWal, Jeremy

    2007-01-01

    Full text: Full text: There is now ample evidence demonstrating the impacts of climate change on biodiversity and human society (Walther ef a/. 2002). Numerous studies have shown climate change is one of the most significant threats to tropical forests, such as the Wet Tropics Heritage Area, due to their high biodiversity and endemism (Pounds ef al. 1999; Hughes 2000; Parmesan and Yohe 2003). Williams ef al. (2003) suggested that small shifts in net primary productivity (NPP) as a result of climate change could lead to potentially massive follow-on effects for the extremely diverse and vulnerable rainforest flora and fauna. It is therefore crucial to explore the relationships between NPP and local biodiversity, especially to create models for different climate change scenarios. Nevertheless, NPP in the Wet Tropics has yet to be estimated. This is the first study to provide a general NPP estimate for the Wet Tropics bioregion using climate surrogates (Schuur 2003). This technique estimates NPP in an accurate, repeatable, and cost-effective way. NPP values were linked to vegetation types and examined under various climatic and environmental conditions. Results show a significant difference in productivity according to vegetation types and climatic variables, with temperature and rainfall seasonality as the most important determining variables. Additionally, lowland and upland vegetations showed a significant difference in productivity patterns throughout the year. Vegetation types located above 1000 metres in altitude had the lowest values of mean annual productivity due to their high rainfall and low temperatures; vegetation types located below 600 metres showed increased productivity values during the wet season (December-March). Net primary productivity will certainly be impacted by changes in temperature and rainfall, due to climate change. Although an increase in NPP values can be predicted for upland areas, the more widely distributed lowlands will drastically

  18. Inertial fusion and energy production

    International Nuclear Information System (INIS)

    Holzrichter, J.F.

    1982-01-01

    Inertial-confinement fusion (ICF) is a technology for releasing nuclear energy from the fusion of light nuclei. For energy production, the most reactive hydrogen isotopes (deuterium (D) and tritium (T)) are commonly considered. The energy aplication requires the compression of a few milligrams of a DT mixture to great density, approximately 1000 times its liquid-state density, and to a high temperature, nearly 100 million 0 K. Under these conditions, efficient nuclear-fusion reactions occur, which can result in over 30% burn-up of the fusion fuel. The high density and temperature can be achieved by focusing very powerful laser or ion beams onto the target. The resultant ablation of the outer layers of the target compresses the fuel in the target, DT ignition occurs, and burn-up of the fuel results as the thermonuclear burn wave propagates outward. The DT-fuel burn-up occurs in about 199 picoseconds. On this short time scale, inertial forces are sufficiently strong to prevent target disassembly before fuel burn-up occurs. The energy released by the DT fusion is projected to be several hundred times greater than the energy delivered by the driver. The present statuds of ICF technology is described

  19. Worldwide clean energy system technology using hydrogen (WE-NET). subtask 9. Investigation of innovative and leading technologies; Suiso riyo kokusai clean energy system gijutsu (WE-NET). subtask 9. Kakushinteki sendoteki gijutsu ni kansuru chosa kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    The WE-NET Project is a long-term project designed to ensure that an energy network technology using hydrogen becomes a reality not later than 2020. So the project cannot remain effective unless constant efforts are made to foresee future trends of technology and optimize it as the making of entire system for the project. In this project, new technologies which are not up for development are also investigated. Their feasibility should be studied, if necessary. From the foregoing point of view, new technologies are studied, collected and evaluated. Thus, useful suggestions and proposals may be made as to the course for the project to follow, as well as its research and development. Proposals highly evaluated up to FY 1995 are the hydrogen-oxygen internal-combustion Stirling`s engine, hydrogen production by solid oxide electrolysis, magnetic refrigeration technology for liquefaction of hydrogen, solar thermal hydrogen production with iron sponge technology, and hydrogen producing technology with photocatalyst. Conceptual investigation themes in FY 1996 are the hydrogen internal-combustion Stirling engine, solar thermal hydrogen production, phototransformation process, and high-temperature steam electrolysis. 9 figs., 54 tabs.

  20. Hydrogen Production Using Nuclear Energy

    Energy Technology Data Exchange (ETDEWEB)

    Verfondern, K. [Research Centre Juelich (Germany)

    2013-03-15

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

  1. Design of advanced solar homes aimed at net-zero annual energy consumption in Canada

    Energy Technology Data Exchange (ETDEWEB)

    Athienitis, Andreas

    2010-09-15

    This paper overviews the design of three sustainable low or net-zero energy solar homes in Canada. The major features of the houses are: 1. direct gain passive solar design that emphasizes utilization of distributed thermal mass in the equatorial-facing part of the ground floor; 2. a building-integrated photovoltaic-thermal system (BIPV/T); 3. a two-stage ground-source heat pump used to heat/cool air in the house or an air source heat pump using BIPV/T air as the source to heat a storage tank; 4. a floor heating system integrated in the floor mass of the direct gain zone; 5. a multizone programmable thermostat.

  2. Expedited Holonomic Quantum Computation via Net Zero-Energy-Cost Control in Decoherence-Free Subspace.

    Science.gov (United States)

    Pyshkin, P V; Luo, Da-Wei; Jing, Jun; You, J Q; Wu, Lian-Ao

    2016-11-25

    Holonomic quantum computation (HQC) may not show its full potential in quantum speedup due to the prerequisite of a long coherent runtime imposed by the adiabatic condition. Here we show that the conventional HQC can be dramatically accelerated by using external control fields, of which the effectiveness is exclusively determined by the integral of the control fields in the time domain. This control scheme can be realized with net zero energy cost and it is fault-tolerant against fluctuation and noise, significantly relaxing the experimental constraints. We demonstrate how to realize the scheme via decoherence-free subspaces. In this way we unify quantum robustness merits of this fault-tolerant control scheme, the conventional HQC and decoherence-free subspace, and propose an expedited holonomic quantum computation protocol.

  3. System of failures diagnosis for energy transmission systems, using Petri nets

    International Nuclear Information System (INIS)

    Zapata, German; Grisales, John Faber; Gomez, Juan Camilo; Quintero Henao, Luis Fernando

    2005-01-01

    An expert system of second generation was used integrating the inverse Petri nets (RPN) and the systems based on rules (rule-based system) for the accomplishment of a program in Visual Basic that helps in the obtaining of an opportune and fast analysis of transmission of energy at the time of happening a fault in anymore of its components (line or bus). The program is proven in a portion of system IEEE -118 standard bus test system, in which two extracted cases of literature are developed and are the obtained results. Finally tests realized with the method developed in the laboratory of machines of the national university of Colombia, Medellin campus, simulating a system of transmission with two lines and two buses

  4. Sub-canopy light conditions only allow low annual net productivity of epiphytic algae on kelp Laminaria hyperborea

    DEFF Research Database (Denmark)

    Pedersen, Morten Foldager; Nejrup, Lars Brammer; Pedersen, Troels Møller

    2014-01-01

    The stipes of older Laminaria hyperborea individuals are heavily covered by epiphytic assemblages that are dominated by macroalgae, and we hypothesized that the production of these algae may contribute significantly to total primary production of the kelp forest ecosystem. The epiphytic assemblages...... through spring as surface irradiance increased. Annual net productivity was relatively low, ranging from 42 to 96 g DW m-2 seafloor depending on site. We conclude that the net productivity of these macroalgal epiphytes is insignificant relative to that of kelp itself, and that the large observed biomass...

  5. Particle production at collider energies

    International Nuclear Information System (INIS)

    Geich-Gimbel, C.

    1987-11-01

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

  6. Comparing World Economic and Net Energy Metrics, Part 3: Macroeconomic Historical and Future Perspectives

    Directory of Open Access Journals (Sweden)

    Carey W. King

    2015-11-01

    Full Text Available I use energy cost share to characterize the role of energy in the economy. Specifically, I use an estimate of monetary expenditures for primary energy on an annualized basis for forty-four countries from 1978 to 2010 for natural gas, coal, petroleum, and electricity. I show that global energy cost share is significantly correlated to a one-year lag in the change in gross domestic product as well as measures of total factor productivity. Given the historical reduction in the relative cost of energy (including food and fodder for animate power since the start of the Industrial Revolution, combined with a global energy cost share estimate, I conclude that the turn of the 21st Century represents the time period with the cheapest energy in the history of human civilization (to date. This potential historical nadir for energy expenditures around 2000 has important ramifications for strategies to solve future social, economic, and environmental problems such as reducing annual emissions of greenhouse gases (GHGs. Rapidly decreasing annual GHG emissions while internalizing their costs into the economy might feedback to increase energy expenditures to such a degree as to prevent economic growth during that transition.

  7. Effects of Climate Change and Shifts in Forest Composition on Forest Net Primary Production

    Institute of Scientific and Technical Information of China (English)

    Jyh-Min Chiang; Louts R. Iverson; Anantha Prasad; Kim J. Brown

    2008-01-01

    Forests are dynamic in both structure and species composition, and these dynamics are strongly Influenced by climate.However, the net effects of future tree species composition on net primary production (NPP) are not well understood. The objective of this work was to model the potential range shifts of tree species (DISTRIB Model) and predict their impacts on NPP (PnET-Ⅱ Model) that will be associated with alterations in species composition. We selected four 200 × 200 km areas In Wisconsin, Maine, Arkansas, and the Ohio-West Virginia area, representing focal areas of potential species range shifts. PnET-Ⅱ model simulations were carried out assuming that all forests achieved steady state, of which the species compositions were predicted by DISTRIB model with no migration limitation. The total NPP under the current climate ranged from 552 to 908 g C/m2 per year. The effects of potential species redistributions on NPP were moderate (-12% to +8%) compared with the influence of future climatic changes (-60% to +25%). The direction and magnitude of climate change effects on NPP were largely dependent on the degree of warming and water balance. Thus, the magnitude of future climate change can affect the feedback system between the atmosphere and biosphere.

  8. Net community production and metabolic balance at the oligotrophic ocean site, station ALOHA

    Science.gov (United States)

    le B. Williams, Peter J.; Morris, Paul J.; Karl, David M.

    2004-11-01

    To test the hypothesis that in oligotrophic areas of the ocean respiration exceeds production, a 12-month study was undertaken of in vitro-determined net oxygen production and consumption in the top 150 m of the water column at the extreme oligotrophic site, Station ALOHA, in the North Pacific subtropical gyre. Throughout the year the water column was observed to be in metabolic deficit, the calculated cumulative shortfall being 9±1.7 mol O2 m-2 a-1 (approximately 100 g C m-2 a-1), an amount equivalent to 40% of measured production (annual estimated rates of production and consumption were, respectively, 22 and 31 mol O2 m-2 a-1). We consider three possible explanations for the observed deficit: the in vitro oxygen rate measurements, in themselves, are fundamentally flawed and should be discounted, the observations are correct and the observed deficit is a true account of the balance of oxygen (and organic carbon) at Station ALOHA, or the observations are correct as they stand, but need not be interpreted as organic carbon imbalance for that ecosystem. We find no error unique to the oxygen rate measurements themselves. We find also no evidence that the associated organic carbon deficit can be sustained over the long-term by internal organic reserves or by external subsidy. Accordingly we accept the geochemical findings that calculated in situ oxygen flux requires the euphotic zone of the water column at this site to be slightly (circa 2 mol C m-2 a-1) autotrophic, in contrast to the simple analysis of our observations which gives a net heterotrophic water column. We discuss a number of processes that may give rise to the observed discrepancy. In part it may derive from the difficulty of reproducing the variations in the light field experienced by an algal cell due to vertical advection. It may also derive from the intermittency of production. This latter effect would manifest itself in the following manner. Because of its universal distribution in the food web

  9. Net ecosystem productivity and carbon dynamics of the traditionally managed Imperata grasslands of North East India.

    Science.gov (United States)

    Pathak, Karabi; Malhi, Yadvinder; Sileshi, G W; Das, Ashesh Kumar; Nath, Arun Jyoti

    2018-09-01

    There have been few comprehensive descriptions of how fire management and harvesting affect the carbon dynamics of grasslands. Grasslands dominated by the invasive weed Imperata cylindrica are considered as environmental threats causing low land productivity throughout the moist tropical regions in Asia. Imperata grasslands in North East India are unique in that they are traditionally managed and culturally important in the rural landscapes. Given the importance of fire in the management of Imperata grassland, we aimed to assess (i) the seasonal pattern of biomass production, (ii) the eventual pathways for the produced biomass, partitioned between in situ decomposition, harvesting and combustion, and (iii) the effect of customary fire management on the ecosystem carbon cycle. Comparatively high biomass production was recorded during pre-monsoon (154 g m -2  month -1 ) and monsoon (214 g m -2  month -1 ) compared to the post-monsoon (91 g m -2  month -1 ) season, and this is attributed to nutrient return into the soil immediately after fire in February. Post fire effects might have killed roots and rhizomes leading to high belowground litter production 30-35 g m -2 during March to August. High autotrophic respiration was recorded during March-July, which was related to high belowground biomass production (35-70 g m -2 ) during that time. Burning removed all the surface litter in March and this appeared to hinder surface decomposition and result in low heterotrophic respiration. Annual total biomass carbon production was estimated at 886 g C m -2 . Annual harvest of biomass (estimated at 577 g C m -2 ) was the major pathway for carbon fluxes from the system. Net ecosystem production (NEP) of Imperata grassland was estimated at 91 g C m -2  yr -1 indicating that these grasslands are a net sink of CO 2 , although this is greatly influenced by weather and fire management. Crown Copyright © 2018. Published by Elsevier B

  10. Photonic microstructures for energy-generating clear glass and net-zero energy buildings

    Science.gov (United States)

    Vasiliev, Mikhail; Alghamedi, Ramzy; Nur-E-Alam, Mohammad; Alameh, Kamal

    2016-01-01

    Transparent energy-harvesting windows are emerging as practical building-integrated photovoltaics (BIPV), capable of generating electricity while simultaneously reducing heating and cooling demands. By incorporating spectrally-selective diffraction gratings as light deflecting structures of high visible transparency into lamination interlayers and using improved spectrally-selective thin-film coatings, most of the visible solar radiation can be transmitted through the glass windows with minimum attenuation. At the same time, the ultraviolet (UV) and a part of incident solar infrared (IR) radiation energy are converted and/or deflected geometrically towards the panel edge for collection by CuInSe2 solar cells. Experimental results show power conversion efficiencies in excess of 3.04% in 10 cm × 10 cm vertically-placed clear glass panels facing direct sunlight, and up to 2.08% in 50 cm × 50 cm installation-ready framed window systems. These results confirm the emergence of a new class of solar window system ready for industrial application. PMID:27550827

  11. Environmental impact of energy production

    International Nuclear Information System (INIS)

    Lidgate, David

    1992-01-01

    Care of the environment is set to be one of the growth industries of the 1990s. Unfortunately, information as to the effect current life styles are having on the environment and, therefore, what remedial action is necessary, varies from the full to the non-existent and, worst of all, from the misleading to the incorrect. For various reasons, some aspects of technology have received greater attention from the media and environmental pressure groups than others. Energy production and conversion technologies, of course, are very much in this category. Indeed, the problem in these areas is not lack of information but a positive surfeit. (author)

  12. Energy dependence of strangeness production and event-byevent fluctuations

    Directory of Open Access Journals (Sweden)

    Rustamov Anar

    2018-01-01

    Full Text Available We review the energy dependence of strangeness production in nucleus-nucleus collisions and contrast it with the experimental observations in pp and p-A collisions at LHC energies as a function of the charged particle multiplicities. For the high multiplicity final states the results from pp and p-Pb reactions systematically approach the values obtained from Pb-Pb collisions. In statistical models this implies an approach to the thermodynamic limit, where differences of mean multiplicities between various formalisms, such as Canonical and Grand Canonical Ensembles, vanish. Furthermore, we report on event-by-event net-proton fluctuations as measured by STAR at RHIC/BNL and by ALICE at LHC/CERN and discuss various non-dynamical contributions to these measurements, which should be properly subtracted before comparison to theoretical calculations on dynamical net-baryon fluctuations.

  13. Nuclear energy for hydrogen production

    International Nuclear Information System (INIS)

    Verfondern, K.

    2007-01-01

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

  14. Successfully Implementing Net-Zero Energy Policy through the Air Force Military Construction Program

    Science.gov (United States)

    2013-03-01

    source, it is necessary to use site-to-source multipliers to account for the prime energy required to transport , produce, and deliver the power...ensure that the roof structure is sufficient. See the American Society of Civil Engineers ( ASCE ) international building code 7-05 for the method of...strip of shading (lightning rods, antennas , etc.) can limit the current of the entire array. Find out what the energy production of the proposed

  15. Combining remote sensing and climatic data to estimate net primary production across Oregon

    International Nuclear Information System (INIS)

    Law, B.E.; Waring, R.H.

    1994-01-01

    A range in productivity and climate exists along an east—west transect in Oregon. Remote sensing and climatic data for several of the Oregon Transect Ecosystem Research Project (OTTER) forested sites and neighboring shrub sites were combined to determined whether percentage intercepted photosynthetically active radiation (%IPAR) can be estimated from remotely sensed observations and to evaluate climatic constraints on the ability of vegetation to utilize intercepted of radiation for production. The Thematic Mappers Simulator (TMS) normalized difference vegetation index (NDVI) provided a good linear estimate of %IPAR (R 2 = 0.97). Vegetation intercepted from 24.8% to 99.9% of incident photosynthetically active radiation (PAR), and aboveground net primary production (ANPP) ranged from 53 to 1310 g·m —2 ·yr —1 . The ANPP was linearly related to annual IPAR across sites (R 2 = 0.70). Constraints on the ability of each species to utilize intercepted light, as defined by differential responses to freezing temperatures, drought, and vapor pressure deficit, were quantified from hourly meteorological station measurements near the sites and field physiological measurements. Vegetation could utilize from 30% of intercepted radiation at the eastside semiarid juniper woodland and shrub sites to 97% at the maritime coastal sites. Energy—size efficiency (ϵu), calculated from aboveground production and IPAR modified by the environmental limits, averaged 0.5 g/MJ for the shrub sites and 0.9 g/MJ for the forested sites. (author)

  16. Net primary productivity of some aquatic macrophytes in sewage-sullage mixture.

    Science.gov (United States)

    Kanungo, V K; Sinha, S; Naik, M L

    2001-07-01

    Sewage-sullage mixture from Raipur city is spread over a vast area surrounding the city. This mixture has a pH always above neutrality with high turbidity. Transparency was nil with the absence of phenolphthalein alkalinity and dissolved oxygen. Hardness was high with low nitrogen and phosphorus concentration. Human consumable. acquatic macrophytes are cultivated in such waste water. Net primary productivity of three macrophytes: Ipomoea aquatica, Marsilea quadrifolia and Nelumbo nucifera were evaluated while being cultivated in such sewage-sullage mixture. Productivity was determined either with periodic biomass removal (I. aquatica and M. quadrifolia) or through removing the biomass only once at the time of growing season (N. nucifera). Growing season productivity of up to 27.48. 19.81 and 9.49 g m(-2) and day(-1) and extrapolated productivity of up to 100.30, 72.31 and 34.64 mt. ha(-1) yr(-1) was recorded for I. aquatica. M. quadrifolia and N. nucifera respectively. Thus, these macrophytes are yielding a high amount of human consumable biomass from an area which neither be a useless wetland.

  17. Estimating Net Primary Production of Swedish Forest Landscapes by Combining Mechanistic Modeling and Remote Sensing

    DEFF Research Database (Denmark)

    Tagesson, Håkan Torbern; Smith, Benjamin; Løfgren, Anders

    2009-01-01

    and the Beer-Lambert law. LAI estimates were compared with satellite-extrapolated field estimates of LAI, and the results were generally acceptable. NPP estimates directly from the dynamic vegetation model and estimates obtained by combining the model estimates with remote sensing information were, on average......The aim of this study was to investigate a combination of satellite images of leaf area index (LAI) with processbased vegetation modeling for the accurate assessment of the carbon balances of Swedish forest ecosystems at the scale of a landscape. Monthly climatologic data were used as inputs...... in a dynamic vegetation model, the Lund Potsdam Jena-General Ecosystem Simulator. Model estimates of net primary production (NPP) and the fraction of absorbed photosynthetic active radiation were constrained by combining them with satellite-based LAI images using a general light use efficiency (LUE) model...

  18. Renewable and non-renewable energy consumption and economic growth: Evidence from MENA Net Oil Exporting Countries.

    OpenAIRE

    Kahia, Montassar; Ben Aissa, Mohamed Safouane

    2014-01-01

    This study investigate the relationship between renewable and non-renewable energy consumption and economic growth in a sample of 13 MENA Net Oil Exporting Countries covering the period 1980–2012 within a multivariate panel framework. The Pedroni (1999, 2004), Kao (1999) as well as the Westerlund (2007) panel cointegration tests indicate that there is a long-run equilibrium relationship between real GDP, renewable energy consumption, non-renewable energy consumption, real gross fixed capital ...

  19. Renewable and non-renewable energy consumption and economic growth: Evidence from MENA Net Oil Importing Countries

    OpenAIRE

    Kahia, Montassar; Ben Aissa, Mohamed Safouane

    2014-01-01

    In this paper, we use panel cointegration techniques to explore the relationship between renewable and non-renewable energy consumption and economic growth in a sample of 11 MENA Net Oil Importing Countries covering the period 1980–2012. The Pedroni (1999, 2004), Kao(1999) as well as Westerlund(2007) panel cointegration tests indicate that there is a long-run equilibrium relationship between real GDP, renewable energy consumption, non-renewable energy consumption, real gross fixed capital for...

  20. Assessing the impact of the urbanization process on net primary productivity in China in 1989–2000

    International Nuclear Information System (INIS)

    Tian, Guangjin; Qiao, Zhi

    2014-01-01

    Urban development affects the material circulation and energy flow of ecosystems, thereby affecting the Net Primary Productivity (NPP). The loss of NPP due to urban expansion was calculated integrating GLO-PEM with remote sensing and GIS techniques in China during the period of 1989–2000. Using urban expansion and the mean NPP for the different land use types in the fourteen regions, the total loss of NPP was calculated as 0.95 Tg C, which accounted for 0.03% of the national NPP of 1989. The total loss of NPP due to the transformation from cropland to urban land accounted for 91.93%, followed by forest (7.17%) and grassland (0.69%). However, the conversion from unused land, industrial and construction land, and water bodies to urban land resulted in an increase in the NPP. The regions locating in eastern China and middle China had large reductions in the total NPP due to urban expansion. -- Highlights: • This paper assesses the impact of urbanization process on net primary productivity in China. • TM images were interpreted to obtain the extent and spatial distribution of urban development. • Using mean NPP for different land uses, we calculated total loss of NPP was 0.949447 Tg C in China. • The total loss of NPP owing to the transformation from cropland to urban land accounted for 91.93%. -- The loss of NPP due to urban expansion was calculated as 0.95 Tg C in China in 1989–2000, which accounted for 0.03% of the national NPP of 1989

  1. Annual nitrate drawdown observed by SOCCOM profiling floats and the relationship to annual net community production

    Science.gov (United States)

    Johnson, Kenneth S.; Plant, Joshua N.; Dunne, John P.; Talley, Lynne D.; Sarmiento, Jorge L.

    2017-08-01

    Annual nitrate cycles have been measured throughout the pelagic waters of the Southern Ocean, including regions with seasonal ice cover and southern hemisphere subtropical zones. Vertically resolved nitrate measurements were made using in situ ultraviolet spectrophotometer (ISUS) and submersible ultraviolet nitrate analyzer (SUNA) optical nitrate sensors deployed on profiling floats. Thirty-one floats returned 40 complete annual cycles. The mean nitrate profile from the month with the highest winter nitrate minus the mean profile from the month with the lowest nitrate yields the annual nitrate drawdown. This quantity was integrated to 200 m depth and converted to carbon using the Redfield ratio to estimate annual net community production (ANCP) throughout the Southern Ocean south of 30°S. A well-defined, zonal mean distribution is found with highest values (3-4 mol C m-2 yr-1) from 40 to 50°S. Lowest values are found in the subtropics and in the seasonal ice zone. The area weighted mean was 2.9 mol C m-2 yr-1 for all regions south of 40°S. Cumulative ANCP south of 50°S is 1.3 Pg C yr-1. This represents about 13% of global ANCP in about 14% of the global ocean area.Plain Language SummaryThis manuscript reports on 40 annual cycles of nitrate observed by chemical sensors on SOCCOM profiling floats. The annual drawdown in nitrate concentration by phytoplankton is used to assess the spatial variability of annual net community production in the Southern Ocean. This ANCP is a key component of the global carbon cycle and it exerts an important control on atmospheric carbon dioxide. We show that the results are consistent with our prior understanding of Southern Ocean ANCP, which has required decades of observations to accumulate. The profiling floats now enable annual resolution of this key process. The results also highlight spatial variability in ANCP in the Southern Ocean.

  2. Preliminary Design of a Solar Photovoltaic Array for Net-Zero Energy Buildings at NASA Langley

    Science.gov (United States)

    Cole, Stuart K.; DeYoung, Russell J.

    2012-01-01

    An investigation was conducted to evaluate photovoltaic (solar electric systems) systems for a single building at NASA Langley as a representative case for alternative sustainable power generation. Building 1250 in the Science Directorate is comprised of office and laboratory space, and currently uses approximately 250,000 kW/month of electrical power with a projected use of 200,000 kW/month with additional conservation measures. The installation would be applied towards a goal for having Building 1250 classified as a net-zero energy building as it would produce as much energy as it uses over the course of a year. Based on the facility s electrical demand, a photovoltaic system and associated hardware were characterized to determine the optimal system, and understand the possible impacts from its deployment. The findings of this investigation reveal that the 1.9 MW photovoltaic electrical system provides favorable and robust results. The solar electric system should supply the needed sustainable power solution especially if operation and maintenance of the system will be considered a significant component of the system deployment.

  3. An approach to prospective consequential life cycle assessment and net energy analysis of distributed electricity generation

    International Nuclear Information System (INIS)

    Jones, Christopher; Gilbert, Paul; Raugei, Marco; Mander, Sarah; Leccisi, Enrica

    2017-01-01

    Increasing distributed renewable electricity generation is one of a number of technology pathways available to policy makers to meet environmental and other sustainability goals. Determining the efficacy of such a pathway for a national electricity system implies evaluating whole system change in future scenarios. Life cycle assessment (LCA) and net energy analysis (NEA) are two methodologies suitable for prospective and consequential analysis of energy performance and associated impacts. This paper discusses the benefits and limitations of prospective and consequential LCA and NEA analysis of distributed generation. It concludes that a combined LCA and NEA approach is a valuable tool for decision makers if a number of recommendations are addressed. Static and dynamic temporal allocation are both needed for a fair comparison of distributed renewables with thermal power stations to account for their different impact profiles over time. The trade-offs between comprehensiveness and uncertainty in consequential analysis should be acknowledged, with system boundary expansion and system simulation models limited to those clearly justified by the research goal. The results of this approach are explorative, rather than for accounting purposes; this interpretive remit, and the assumptions in scenarios and system models on which results are contingent, must be clear to end users. - Highlights: • A common LCA and NEA framework for prospective, consequential analysis is discussed. • Approach to combined LCA and NEA of distributed generation scenarios is proposed. • Static and dynamic temporal allocation needed to assess distributed generation uptake.

  4. Energy consumption and net CO2 sequestration of aqueous mineral carbonation

    International Nuclear Information System (INIS)

    Huijgen, W.J.J.; Ruijg, G.J.; Comans, R.N.J.; Witkamp, G.J.

    2006-12-01

    Aqueous mineral carbonation is a potentially attractive sequestration technology to reduce CO2 emissions. The energy consumption of this technology, however, reduces the net amount of CO2 sequestered. Therefore, the energetic CO2 sequestration efficiency of aqueous mineral carbonation was studied in dependence of various process variables using either wollastonite (CaSiO3) or steel slag as feedstock. For wollastonite, the maximum energetic CO2 sequestration efficiency within the ranges of process conditions studied was 75% at 200C, 20 bar CO2, and a particle size of <38μm. The main energy-consuming process steps were the grinding of the feedstock and the compression of the CO2 feed. At these process conditions, a significantly lower efficiency was determined for steel slag (69%), mainly because of the lower Ca content of the feedstock. The CO2 sequestration efficiency might be improved substantially for both types of feedstock by, e.g., reducing the amount of process water applied and further grinding of the feedstock. The calculated energetic efficiencies warrant a further assessment of the (energetic) feasibility of CO2 sequestration by aqueous mineral carbonation on the basis of a pilot-scale process

  5. Pirates and Samaritans : a decade of measurements on peer production and their implications for net neutrality and copyright

    NARCIS (Netherlands)

    Pouwelse, J.A.; Garbacki, P.; Epema, D.H.J.; Sips, H.J.

    2008-01-01

    This study traces the evolution of commons-based peer production by a measurement-based analysis of case studies and discusses the impact of peer production on net neutrality and copyright law. The measurements include websites such as suprnova.org, youtube.com, and facebook.com, and the

  6. Energy productivity and efficiency of wheat farming in Bangladesh

    International Nuclear Information System (INIS)

    Rahman, Sanzidur; Hasan, M. Kamrul

    2014-01-01

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

  7. Comparing the impact of the 2003 and 2010 heatwaves on Net Ecosystem Production in Europe

    Science.gov (United States)

    Bastos, A. F.; Gouveia, C. M.; Trigo, R. M.

    2012-12-01

    Climate variability is known to influence primary productivity on land ecosystems (Nemani et al., 2003). In particular, extreme climatic events such as major droughts and heatwaves are known to have severe impact on primary productivity and, therefore, to affect significantly the carbon dioxide uptake by land ecosystems at regional (Ciais et al., 2005) or even global scale (Zhao and Running, 2010). In the last decade, Europe was struck by two outstanding heatwaves, the 2003 event in Western Europe and the recent 2010 episode over Eastern Europe. Both were characterised by record breaking temperatures at the daily, weekly, monthly and seasonal scales, although the amplitude and spatial extent of the 2010 mega-heatwave surpassed the 2003 event (Barriopedro et al., 2011). This work aims to assess the influence of both mega-heatwaves on seasonal and yearly Net Ecosystem Production (NEP). The work relies on monthly NEP data derived from satellite imagery obtained from MODIS (Moderate Resolution Imaging Spectroradiometer) sensor at 1km spatial resolution. Data were selected for the period between 2000 and 2011 over a region extending from 34.6 oN to 73.5 oN and 12.1 oW to 46.8 oE, covering Eurasia. In 2010 very low NEP anomalies are observed over a very large area in Eastern Europe, at the monthly, seasonal and yearly scale. In western Russia, yearly NEP anomalies fall below 50% of average cumulative NEP. These widespread negative anomalous values of NEP fields over the western Russia region match the patterns of very high temperature values combined with below-average precipitation, at the seasonal (summer) scale. Moreover, the impact of the heatwave is not only evident at the regional level but also at the wider continental (European) scale and is significantly more extensive and intense than the corresponding heatwave of 2003 in Western Europe (Ciais et al., 2005). References: Barriopedro, D., E. M. Fischer, J. Luterbacher, R. M. Trigo, and R. Garcia-Herrera (2011

  8. Experimental on-line platform for product conceptual design: OpenDesigNet

    Directory of Open Access Journals (Sweden)

    Teresa Magal-Royo

    2013-09-01

    Full Text Available This paper highlights the need for using specialised on-line collaborative environments by designers and product engineers who increasingly use Web 2.0 technology to search for information. Although there are professional channels and networks, there is no specific platform which helps during a new product’s conceptualisation phase. Open communication must thus be promoted and encouraged amongst design professionals and companies to form working groups thereby allowing them to work collaboratively in the most open and creative phase of product design, i.e. conceptualisation. The OpenDesigNet (ODN experimental platform has been developed so that designers and small- or medium-sized companies (SMC can access on-line collaborative tools to support the creation and promotion of new on-line products and assess their immediate social impact. This article presents some of the results obtained during the validation phase involving a platform satisfaction survey of design engineering students and has led to a first-hand assessment of the new platform’s potential impact on their professional future.

  9. International Clean Energy System Using Hydrogen Conversion (WE-NET). subtask 3. Study on the global network; Suiso riyo kokusai clean energy system gijutsu (WE-NET). subtask 3. Global network kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    As a part of the WE-NET project, the introduction condition of hydrogen as substituting energy and CO2 reduction effect were analyzed using a global energy model. The WE-NET project aims at global-wide introduction of clean energy by converting abundant renewable clean energy into hydrogen transportable to distant consumers all over the world. The study result in fiscal 1996 is as follows. Undeveloped hydroelectric resources in the world are estimated to be 12 trillion kWh/y equivalent to the existing developed one in the world. Since the cost of the hydroelectric power generation projects over 1000MW in the planning stage is estimated to be 0.02-0.05$/kWh lower than that of other renewable energies, such projects are expected as energy source in the initial stage of the practical WE-NET project. The GREEN model was modified by adding a hydrogen analysis function, and extending an analysis period. The modified model allowed evaluation of the long-term important role of hydrogen energy, in particular, the capability of CO2 gas reduction all over the world. 28 refs., 92 figs., 56 tabs.

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

    Directory of Open Access Journals (Sweden)

    Sama Amid

    2016-06-01

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

  11. Applying and Individual-Based Model to Simultaneously Evaluate Net Ecosystem Production and Tree Diameter Increment

    Science.gov (United States)

    Fang, F. J.

    2017-12-01

    Reconciling observations at fundamentally different scales is central in understanding the global carbon cycle. This study investigates a model-based melding of forest inventory data, remote-sensing data and micrometeorological-station data ("flux towers" estimating forest heat, CO2 and H2O fluxes). The individual tree-based model FORCCHN was used to evaluate the tree DBH increment and forest carbon fluxes. These are the first simultaneous simulations of the forest carbon budgets from flux towers and individual-tree growth estimates of forest carbon budgets using the continuous forest inventory data — under circumstances in which both predictions can be tested. Along with the global implications of such findings, this also improves the capacity for forest sustainable management and the comprehensive understanding of forest ecosystems. In forest ecology, diameter at breast height (DBH) of a tree significantly determines an individual tree's cross-sectional sapwood area, its biomass and carbon storage. Evaluation the annual DBH increment (ΔDBH) of an individual tree is central to understanding tree growth and forest ecology. Ecosystem Carbon flux is a consequence of key ecosystem processes in the forest-ecosystem carbon cycle, Gross and Net Primary Production (GPP and NPP, respectively) and Net Ecosystem Respiration (NEP). All of these closely relate with tree DBH changes and tree death. Despite advances in evaluating forest carbon fluxes with flux towers and forest inventories for individual tree ΔDBH, few current ecological models can simultaneously quantify and predict the tree ΔDBH and forest carbon flux.

  12. The Central Logic Board for the KM3NeT detector: Design and production

    Energy Technology Data Exchange (ETDEWEB)

    Musico, P., E-mail: Paolo.Musico@ge.infn.it

    2016-07-11

    The KM3NeT deep sea neutrino observatory will include a very large number of multi-Photomultiplier (PMT) optical modules (DOM) to detect the Cherenkov light generated by secondary particles produced in neutrino interactions. The Central Logic Board (CLB) has been developed to acquire timing and amplitude information from the PMT signals, implementing time-to-digital conversion (TDC) with time over threshold (TOT) technique. The board is also used to configure all the DOM subsystems, to assist in the DOM position and orientation, calibration and to monitor temperature and humidity in the DOM itself. All the collected data are transmitted to shore using a wide-bandwidth optical network. Moreover, through the optical network, all the DOMs are kept synchronized in time within 1 ns precision using the White Rabbit (WR) Precision Time Protocol (PTP) over an Ethernet connection. A large Field Programmable Gate Array (FPGA) has been adopted to implement all the specifications witht the requested performances. The CLB will be also used in the base container of the detection unit (DU) to set-up and monitor all the requested functionalities: in this scenario a dedicated firmware and software will be deployed on board. The design has been started in early 2013 and several prototypes have been developed. After deep test carried on in different EU laboratories, the final mass production batch of 600 boards has been ordered and built: all the CLB are now ready for integration in the DOMs and base containers. The first two KM3NeT DU will be deployed in summer 2015 and all other units are in advanced stage of integration.

  13. The Central Logic Board for the KM3NeT detector: Design and production

    International Nuclear Information System (INIS)

    Musico, P.

    2016-01-01

    The KM3NeT deep sea neutrino observatory will include a very large number of multi-Photomultiplier (PMT) optical modules (DOM) to detect the Cherenkov light generated by secondary particles produced in neutrino interactions. The Central Logic Board (CLB) has been developed to acquire timing and amplitude information from the PMT signals, implementing time-to-digital conversion (TDC) with time over threshold (TOT) technique. The board is also used to configure all the DOM subsystems, to assist in the DOM position and orientation, calibration and to monitor temperature and humidity in the DOM itself. All the collected data are transmitted to shore using a wide-bandwidth optical network. Moreover, through the optical network, all the DOMs are kept synchronized in time within 1 ns precision using the White Rabbit (WR) Precision Time Protocol (PTP) over an Ethernet connection. A large Field Programmable Gate Array (FPGA) has been adopted to implement all the specifications witht the requested performances. The CLB will be also used in the base container of the detection unit (DU) to set-up and monitor all the requested functionalities: in this scenario a dedicated firmware and software will be deployed on board. The design has been started in early 2013 and several prototypes have been developed. After deep test carried on in different EU laboratories, the final mass production batch of 600 boards has been ordered and built: all the CLB are now ready for integration in the DOMs and base containers. The first two KM3NeT DU will be deployed in summer 2015 and all other units are in advanced stage of integration.

  14. Successional changes in live and dead wood carbon stores: implications for net ecosystem productivity.

    Science.gov (United States)

    Janisch, J E; Harmon, M E

    2002-02-01

    If forests are to be used in CO2 mitigation projects, it is essential to understand and quantify the impacts of disturbance on net ecosystem productivity (NEP; i.e., the change in ecosystem carbon (C) storage with time). We examined the influence of live tree and coarse woody debris (CWD) on NEP during secondary succession based on data collected along a 500-year chronosequence on the Wind River Ranger District, Washington. We developed a simple statistical model of live and dead wood accumulation and decomposition to predict changes in the woody component of NEP, which we call NEP(w). The transition from negative to positive NEP(w), for a series of scenarios in which none to all wood was left after disturbance, occurred between 0 and 57 years after disturbance. The timing of this transition decreased as live-tree growth rates increased, and increased as CWD left after disturbance increased. Maximum and minimum NEP(w) for all scenarios were 3.9 and -14.1 Mg C ha-1 year-1, respectively. Maximum live and total wood C stores of 319 and 393 Mg C ha(-1), respectively, were reached approximately 200 years after disturbance. Decomposition rates (k) of CWD ranged between 0.013 and 0.043 year-1 for individual stands. Regenerating stands took 41 years to attain a mean live wood mass equivalent to the mean mass of CWD left behind after logging, 40 years to equal the mean CWD mass in 500-year-old forest, and more than 150 years to equal the mean total live and dead wood in an old-growth stand. At a rotation age of 80 years, regenerating stands stored approximately half the wood C of the remaining nearby old-growth forests (predominant age 500 years), indicating that conversion of old-growth forests to younger managed forests results in a significant net release of C to the atmosphere.

  15. Plywood production wastes to energy

    Science.gov (United States)

    Lyubov, V. K.; Popov, A. N.

    2017-11-01

    Wood and by-products of its processing are a renewable energy source with carbon neutral and may be used in solving energy problems. ZAO «Arkhangelsk plywood factory» installed and put into operation the boiler with capacity of 22 MW (saturated steam of 1.2 MPa) to reduce the cost of thermal energy, the impact of environmental factors on stability of the company’s development and for reduction of harmful emissions into the environment. Fuel for boiler is the mixture consists of chip plywood, birch bark, wood sanding dust (WSD) and sawdust of the plywood processing. The components of the fuel mixture significantly differ in thermotechnical characteristics and technological parameters but especially in size composition. Particle dimensions in the fuel mixture differ by more than a thousand times which makes it «unique» and very difficult to ensure the effective and non-explosive use. WSD and sawdust from line of cutting of plywood are small fraction material and relate to IV group of explosion. Criterion of explosive for them has great values (КfWSD=10.85 Кfsaw=9.66). Boiler’s furnace equipped with reciprocating grate where implemented a three-stage scheme of combustion. For a comprehensive survey of the effectiveness of installed equipment was analyzed the design features of the boiler, defined the components of thermal balance, studied nitrogen oxide emissions, carbon and particulate matter with the determination of soot emissions. Amount of solid particles depending on their shape and size was analyzed.

  16. A NetCDF version of the two-dimensional energy balance model based on the full multigrid algorithm

    Science.gov (United States)

    Zhuang, Kelin; North, Gerald R.; Stevens, Mark J.

    A NetCDF version of the two-dimensional energy balance model based on the full multigrid method in Fortran is introduced for both pedagogical and research purposes. Based on the land-sea-ice distribution, orbital elements, greenhouse gases concentration, and albedo, the code calculates the global seasonal surface temperature. A step-by-step guide with examples is provided for practice.

  17. A Governance Perspective on Net Zero Energy Building Niche Development in India: The Case of New Delhi

    NARCIS (Netherlands)

    Jain, Mansi; Hoppe, T.; Bressers, Hans

    2017-01-01

    The net zero-energy building (NZEB) concept has recently gained prominence worldwide. Large scale adoption and implementation of NZEBs would potentially contribute greatly to greening of the building sector. However, it is still at a nascent stage of niche formation. This paper aims to assess the

  18. A governance perspective on net zero energy building niche development in India : The case of New Delhi

    NARCIS (Netherlands)

    Jain, Mansi; Hoppe, Thomas; Bressers, Hans

    2017-01-01

    The net zero-energy building (NZEB) concept has recently gained prominence worldwide. Large scale adoption and implementation of NZEBs would potentially contribute greatly to greening of the building sector. However, it is still at a nascent stage of niche formation. This paper aims to assess the

  19. Flood effects on efflux and net production of nitrous oxide in river floodplain soils

    Science.gov (United States)

    Riaz, Muhammad; Bruderer, Christian; Niklaus, Pascal A.; Luster, Jörg

    2016-04-01

    Floodplain soils are often rich in nutrients and exhibit high spatial heterogeneity in terms of geomorphology, soil environmental conditions and substrate availability for processes involved in carbon and nutrient cycling. In addition, fluctuating water tables lead to temporally changing redox conditions. In such systems, there are ideal conditions for the occurrence of hot spots and moments of nitrous oxide emissions, a potent greenhouse gas. The factors that govern the spatial heterogeneity and dynamics of N2O formation in floodplain soils and the surface efflux of this gas are not fully understood. A particular issue is the contribution of N2O formation in the subsoil to surface efflux. We studied this question in the floodplain of a restored section of the Thur river (NE Switzerland) which is characterized by a flashy flow regime. As a consequence, the floodplain soils are unsaturated most of the time. We showed earlier that saturation during flood pulses leads to short phases of generally anoxic conditions followed by a drying phase with anoxic conditions within aggregates and oxic conditions in larger soil pores. The latter conditions are conducive for spatially closely-coupled nitrification-denitrification and related hot moments of nitrous oxide formation. In a floodplain zone characterized by about one meter of young, sandy sediments, that are mostly covered by the tall grass Phalaris arundinacea, we measured at several time points before and after a small flood event N2O surface efflux with the closed-chamber method, and assessed N2O concentrations in the soil air at four different depths using gas-permeable tubings. In addition, we calculated the N2O diffusivity in the soil from Radon diffusivity. The latter was estimated in-situ from the recovery of Radon concentration in the gas-permeable tubings after purging with ambient air. All these data were then used to calculate net N2O production rates at different soil depths with the gradient method. In

  20. Estimating Net Primary Productivity Beneath Snowpack Using Snowpack Radiative Transfer Modeling and Global Satellite Data

    Science.gov (United States)

    Barber, D. E.; Peterson, M. C.

    2002-05-01

    Sufficient photosynthetically active radiation (PAR) penetrates snow for plants to grow beneath snowpack during late winter or early spring in tundra ecosystems. During the spring in this ecosystem, the snowpack creates an environment with higher humidity and less variable and milder temperatures than on the snow-free land. Under these conditions, the amount of PAR available is likely to be the limiting factor for plant growth. Current methods for determining net primary productivity (NPP) of tundra ecosystems do not account for this plant growth beneath snowpack, apparently resulting in underestimating plant production there. We are currently in the process of estimating the magnitude of this early growth beneath snow for tundra ecosystems. Our method includes a radiative transfer model that simulates diffuse and direct PAR penetrating snowpack based on downwelling PAR values and snow depth data from global satellite databases. These PAR levels are convolved with plant growth for vegetation that thrives beneath snowpacks, such as lichen. We expect to present the net primary production for Cladonia species (a common Arctic lichen) that has the capability of photosynthesizing at low temperatures beneath snowpack. This method may also be used to study photosynthesis beneath snowpacks in other hardy plants. Lichens are used here as they are common in snow-covered regions, flourish under snowpack, and provide an important food source for tundra herbivores (e.g. caribou). In addition, lichens are common in arctic-alpine environments and our results can be applied to these ecosystems as well. Finally, the NPP of lichen beneath snowpack is relatively well understood compared to other plants, making it ideal vegetation for this first effort at estimating the potential importance of photosynthesis at large scales. We are examining other candidate plants for their photosynthetic potential beneath snowpack at this time; however, little research has been done on this topic. We

  1. Effects of topography on simulated net primary productivity at landscape scale.

    Science.gov (United States)

    Chen, X F; Chen, J M; An, S Q; Ju, W M

    2007-11-01

    Local topography significantly affects spatial variations of climatic variables and soil water movement in complex terrain. Therefore, the distribution and productivity of ecosystems are closely linked to topography. Using a coupled terrestrial carbon and hydrological model (BEPS-TerrainLab model), the topographic effects on the net primary productivity (NPP) are analyzed through four modelling experiments for a 5700 km(2) area in Baohe River basin, Shaanxi Province, northwest of China. The model was able to capture 81% of the variability in NPP estimated from tree rings, with a mean relative error of 3.1%. The average NPP in 2003 for the study area was 741 gCm(-2)yr(-1) from a model run including topographic effects on the distributions of climate variables and lateral flow of ground water. Topography has considerable effect on NPP, which peaks near 1350 m above the sea level. An elevation increase of 100 m above this level reduces the average annual NPP by about 25 gCm(-2). The terrain aspect gives rise to a NPP change of 5% for forests located below 1900 m as a result of its influence on incident solar radiation. For the whole study area, a simulation totally excluding topographic effects on the distributions of climatic variables and ground water movement overestimated the average NPP by 5%.

  2. Measurements and simulation of forest leaf area index and net primary productivity in Northern China.

    Science.gov (United States)

    Wang, P; Sun, R; Hu, J; Zhu, Q; Zhou, Y; Li, L; Chen, J M

    2007-11-01

    Large scale process-based modeling is a useful approach to estimate distributions of global net primary productivity (NPP). In this paper, in order to validate an existing NPP model with observed data at site level, field experiments were conducted at three sites in northern China. One site is located in Qilian Mountain in Gansu Province, and the other two sites are in Changbaishan Natural Reserve and Dunhua County in Jilin Province. Detailed field experiments are discussed and field data are used to validate the simulated NPP. Remotely sensed images including Landsat Enhanced Thematic Mapper plus (ETM+, 30 m spatial resolution in visible and near infrared bands) and Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER, 15m spatial resolution in visible and near infrared bands) are used to derive maps of land cover, leaf area index, and biomass. Based on these maps, field measured data, soil texture and daily meteorological data, NPP of these sites are simulated for year 2001 with the boreal ecosystem productivity simulator (BEPS). The NPP in these sites ranges from 80 to 800 gCm(-2)a(-1). The observed NPP agrees well with the modeled NPP. This study suggests that BEPS can be used to estimate NPP in northern China if remotely sensed images of high spatial resolution are available.

  3. A biophysical process based approach for estimating net primary production using satellite and ground observations

    Science.gov (United States)

    Choudhury, Bhaskar J.

    An approach is presented for calculating interannual variation of net primary production (C) of terrestrial plant communities at regional scale using satellite and ground measurements. C has been calculated as the difference of gross photosynthesis (A g) and respiration (R), recognizing that different biophysical factors exert major control on these two processes. A g has been expressed as the product of radiation use efficiency for gross photosynthesis by an unstressed canopy and intercepted photosynthetically active radiation, which is then adjusted for stresses due to soil water shortage and temperature away from optimum. R has been calculated as the sum of growth and maintenance components (respectively, R g and R m. The R m has been determined from nitrogen content of plant tissue per unit ground area, while R g has been obtained as a fraction of the difference of A g and R m. Model parameters have not been determined by matching the calculated fluxes against observations at any location. Results are presented for cultivated and temperate deciduous forest areas over North America for five consecutive years (1986-1990) and compared with observations.

  4. Net primary productivity and its partitioning in response to precipitation gradient in an alpine meadow.

    Science.gov (United States)

    Zhang, Fangyue; Quan, Quan; Song, Bing; Sun, Jian; Chen, Youjun; Zhou, Qingping; Niu, Shuli

    2017-11-09

    The dynamics of net primary productivity (NPP) and its partitioning to the aboveground versus belowground are of fundamental importance to understand carbon cycling and its feedback to climate change. However, the responses of NPP and its partitioning to precipitation gradient are poorly understood. We conducted a manipulative field experiment with six precipitation treatments (1/12 P, 1/4 P, 1/2 P, 3/4 P, P, and 5/4 P, P is annual precipitation) in an alpine meadow to examine aboveground and belowground NPP (ANPP and BNPP) in response to precipitation gradient in 2015 and 2016. We found that changes in precipitation had no significant impact on ANPP or belowground biomass in 2015. Compared with control, only the extremely drought treatment (1/12 P) significantly reduced ANPP by 37.68% and increased BNPP at the depth of 20-40 cm by 80.59% in 2016. Across the gradient, ANPP showed a nonlinear response to precipitation amount in 2016. Neither BNPP nor NPP had significant relationship with precipitation changes. The variance in ANPP were mostly due to forbs production, which was ultimately caused by altering soil water content and soil inorganic nitrogen concentration. The nonlinear precipitation-ANPP relationship indicates that future precipitation changes especially extreme drought will dramatically decrease ANPP and push this ecosystem beyond threshold.

  5. Inferring biome-scale net primary productivity from tree-ring isotopes

    Science.gov (United States)

    Pederson, N.; Levesque, M.; Williams, A. P.; Hobi, M. L.; Smith, W. K.; Andreu-Hayles, L.

    2017-12-01

    Satellite estimates of vegetation growth (net primary productivity; NPP), tree-ring records, and forest inventories indicate that ongoing climate change and rising atmospheric CO2 concentration are altering productivity and carbon storage of forests worldwide. The impact of global change on the trends of NPP, however, remain unknown because of the lack of long-term high-resolution NPP data. For the first time, we tested if annually resolved carbon (δ13C) and oxygen (δ18O) stable isotopes from the cellulose of tree rings from trees in temperate regions could be used as a tool for inferring NPP across spatiotemporal scales. We compared satellite NPP estimates from the moderate-resolution imaging spectroradiometer sensor (MODIS, product MOD17A) and a newly developed global NPP dataset derived from the Global Inventory Modeling and Mapping Studies (GIMMS) dataset to annually resolved tree-ring width and δ13C and δ18O records from four sites along a hydroclimatic gradient in Eastern and Central United States. We found strong correlations across large geographical regions between satellite-derived NPP and tree-ring isotopes that ranged from -0.40 to -0.91. Notably, tree-ring derived δ18O had the strongest relation to climate. The results were consistent among the studied tree species (Quercus rubra and Liriodendron tulipifera) and along the hydroclimatic conditions of our network. Our study indicates that tree-ring isotopes can potentially be used to reconstruct NPP in time and space. As such, our findings represent an important breakthrough for estimating long-term changes in vegetation productivity at the biome scale.

  6. Aboveground Net Primary Productivity in a Riparian Wetland Following Restoration of Hydrology

    Directory of Open Access Journals (Sweden)

    Melissa Koontz

    2016-02-01

    Full Text Available This research presents the initial results of the effects of hydrological restoration on forested wetlands in the Mississippi alluvial plain near Memphis, Tennessee. Measurements were carried out in a secondary channel, the Loosahatchie Chute, in which rock dikes were constructed in the 1960s to keep most flow in the main navigation channel. In 2008–2009, the dikes were notched to allow more flow into the secondary channel. Study sites were established based on relative distance downstream of the notched dikes. Additionally, a reference site was established north of the Loosahatchie Chute where the dikes remained unnotched. We compared various components of vegetation composition and productivity at sites in the riparian wetlands for two years. Salix nigra had the highest Importance Value at every site. Species with minor Importance Values were Celtis laevigata, Acer rubrum, and Plantanus occidentalis. Productivity increased more following the introduction of river water in affected sites compared to the reference. Aboveground net primary productivity was highest at the reference site (2926 ± 458.1 g·m−2·year−1, the intact site; however, there were greater increase at the sites in the Loosahatchie Chute, where measurements ranged from 1197.7 ± 160.0 g m−2·year−1·to 2874.2 ± 794.0 g·m−2·year−1. The site furthest from the notching was the most affected. Pulsed inputs into these wetlands may enhance forested wetland productivity. Continued monitoring will quantify impacts of restored channel hydrology along the Mississippi River.

  7. Aboveground Net Primary Productivity in a Riparian Wetland Following Restoration of Hydrology.

    Science.gov (United States)

    Koontz, Melissa; Lundberg, Christopher; Lane, Robert; Day, John; Pezeshki, Reza

    2016-02-04

    This research presents the initial results of the effects of hydrological restoration on forested wetlands in the Mississippi alluvial plain near Memphis, Tennessee. Measurements were carried out in a secondary channel, the Loosahatchie Chute, in which rock dikes were constructed in the 1960s to keep most flow in the main navigation channel. In 2008-2009, the dikes were notched to allow more flow into the secondary channel. Study sites were established based on relative distance downstream of the notched dikes. Additionally, a reference site was established north of the Loosahatchie Chute where the dikes remained unnotched. We compared various components of vegetation composition and productivity at sites in the riparian wetlands for two years. Salix nigra had the highest Importance Value at every site. Species with minor Importance Values were Celtis laevigata, Acer rubrum, and Plantanus occidentalis. Productivity increased more following the introduction of river water in affected sites compared to the reference. Aboveground net primary productivity was highest at the reference site (2926 ± 458.1 g·m(-2)·year(-1)), the intact site; however, there were greater increase at the sites in the Loosahatchie Chute, where measurements ranged from 1197.7 ± 160.0 g m(-2)·year(-1)·to 2874.2 ± 794.0 g·m(-2)·year(-1). The site furthest from the notching was the most affected. Pulsed inputs into these wetlands may enhance forested wetland productivity. Continued monitoring will quantify impacts of restored channel hydrology along the Mississippi River.

  8. Waste incineration with production of clean and reliable energy

    Energy Technology Data Exchange (ETDEWEB)

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

    2011-08-15

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

  9. Achieving energy efficiency through product policy: the UK experience

    International Nuclear Information System (INIS)

    Boardman, Brenda

    2004-01-01

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

  10. A Timed Colored Petri Net Simulation-Based Self-Adaptive Collaboration Method for Production-Logistics Systems

    OpenAIRE

    Zhengang Guo; Yingfeng Zhang; Xibin Zhao; Xiaoyu Song

    2017-01-01

    Complex and customized manufacturing requires a high level of collaboration between production and logistics in a flexible production system. With the widespread use of Internet of Things technology in manufacturing, a great amount of real-time and multi-source manufacturing data and logistics data is created, that can be used to perform production-logistics collaboration. To solve the aforementioned problems, this paper proposes a timed colored Petri net simulation-based self-adaptive colla...

  11. Competition between biomass and food production in the presence of energy policies: a partial equilibrium analysis

    NARCIS (Netherlands)

    Ignaciuk, A.; Vöhringer, F.; Ruijs, A.J.W.; Ierland, van E.C.

    2006-01-01

    Bioenergy has several advantages over fossil fuels. For example, it delivers energy at low net CO2 emission levels and contributes to sustaining future energy supplies. The concern, however, is that an increase in biomass plantations will reduce the land available for agricultural production. The

  12. Methodologies on estimating the energy requirements for maintenance and determining the net energy contents of feed ingredients in swine: a review of recent work.

    Science.gov (United States)

    Li, Zhongchao; Liu, Hu; Li, Yakui; Lv, Zhiqian; Liu, Ling; Lai, Changhua; Wang, Junjun; Wang, Fenglai; Li, Defa; Zhang, Shuai

    2018-01-01

    In the past two decades, a considerable amount of research has focused on the determination of the digestible (DE) and metabolizable energy (ME) contents of feed ingredients fed to swine. Compared with the DE and ME systems, the net energy (NE) system is assumed to be the most accurate estimate of the energy actually available to the animal. However, published data pertaining to the measured NE content of ingredients fed to growing pigs are limited. Therefore, the Feed Data Group at the Ministry of Agricultural Feed Industry Centre (MAFIC) located at China Agricultural University has evaluated the NE content of many ingredients using indirect calorimetry. The present review summarizes the NE research works conducted at MAFIC and compares these results with those from other research groups on methodological aspect. These research projects mainly focus on estimating the energy requirements for maintenance and its impact on the determination, prediction, and validation of the NE content of several ingredients fed to swine. The estimation of maintenance energy is affected by methodology, growth stage, and previous feeding level. The fasting heat production method and the curvilinear regression method were used in MAFIC to estimate the NE requirement for maintenance. The NE contents of different feedstuffs were determined using indirect calorimetry through standard experimental procedure in MAFIC. Previously generated NE equations can also be used to predict NE in situations where calorimeters are not available. Although popular, the caloric efficiency is not a generally accepted method to validate the energy content of individual feedstuffs. In the future, more accurate and dynamic NE prediction equations aiming at specific ingredients should be established, and more practical validation approaches need to be developed.

  13. Energy production from renewable energy sources

    International Nuclear Information System (INIS)

    2001-04-01

    This table summarizes the electricity and heat produced in France and in overseas departments from renewable energy sources for 1998 (revised), 1999 (temporary) and 2000 (estimated): hydraulic, wind, solar photovoltaic and thermal, geothermal, solid municipal wastes, wood and wood wastes, biogas, ethanol and ester bio-fuels. (J.S.)

  14. Adaptations of hepatic amino acid uptake and net utilisation contributes to nitrogen economy or waste in lambs fed nitrogen- or energy-deficient diets.

    Science.gov (United States)

    Kraft, G; Ortigues-Marty, I; Durand, D; Rémond, D; Jardé, T; Bequette, B; Savary-Auzeloux, I

    2011-04-01

    We investigated the effect of relative changes in dietary nitrogen (N) and energy supply and the subsequent variations in net portal appearance (NPA) of nitrogenous and energy nutrients on the net amino acid (AA) uptake by the liver and net N supply to the peripheral tissues. Six lambs were catheterised across the splanchnic tissues and received, in a replicated Latin square, one of three dietary treatments. The diets were formulated to either match the requirements of N and energy (C), or supply only 0.8 of the N requirement (LN) or 0.8 of the energy requirement (LE). Net fluxes of AA and urea-N were measured across the portal-drained viscera, and estimation of arterial hepatic flow allowed the estimation of hepatic fluxes. Catheters were implanted into the portal and hepatic veins as well as in the abdominal aorta for the measurement of AA fluxes. Animals fed the LN diet showed more efficient N retention (0.59 of digested N) than did the C and LE diet (0.50 and 0.33, respectively; P < 0.001). The NPA of total AA-N for the LN diet was only 0.60 of the value measured for the control (C) diet (P < 0.01). Despite this, the total estimated AA-N net splanchnic fluxes were not significantly different across the three diets (3.3, 1.9 and 2.6 g total AA-N/day for C, LN and LE, respectively, P = 0.52). Thus, different metabolic regulations must have taken place across the liver between the three experimental diets. A combination of decreased net uptake of total AA-N by the liver of animals in the LN diet (0.61 of the C diet; P = 0.002) and reduced urinary urea-N production (0.52 of the C diet; P = 0.001) spared AA from catabolism in the LN diet relative to the other two diets. For the LE diet, the urinary urea-N output was 1.3 times the value of the C diet (P = 0.01). This may relate to an increased catabolism of AA by the muscle and/or, to a lesser extent, to an increased utilisation of AA for gluconeogenesis in the liver. These effects may explain the reduced whole body

  15. Net primary productivity of China's terrestrial ecosystems from a process model driven by remote sensing.

    Science.gov (United States)

    Feng, X; Liu, G; Chen, J M; Chen, M; Liu, J; Ju, W M; Sun, R; Zhou, W

    2007-11-01

    The terrestrial carbon cycle is one of the foci in global climate change research. Simulating net primary productivity (NPP) of terrestrial ecosystems is important for carbon cycle research. In this study, China's terrestrial NPP was simulated using the Boreal Ecosystem Productivity Simulator (BEPS), a carbon-water coupled process model based on remote sensing inputs. For these purposes, a national-wide database (including leaf area index, land cover, meteorology, vegetation and soil) at a 1 km resolution and a validation database were established. Using these databases and BEPS, daily maps of NPP for the entire China's landmass in 2001 were produced, and gross primary productivity (GPP) and autotrophic respiration (RA) were estimated. Using the simulated results, we explore temporal-spatial patterns of China's terrestrial NPP and the mechanisms of its responses to various environmental factors. The total NPP and mean NPP of China's landmass were 2.235 GtC and 235.2 gCm(-2)yr(-1), respectively; the total GPP and mean GPP were 4.418 GtC and 465 gCm(-2)yr(-1); and the total RA and mean RA were 2.227 GtC and 234 gCm(-2)yr(-1), respectively. On average, NPP was 50.6% of GPP. In addition, statistical analysis of NPP of different land cover types was conducted, and spatiotemporal patterns of NPP were investigated. The response of NPP to changes in some key factors such as LAI, precipitation, temperature, solar radiation, VPD and AWC are evaluated and discussed.

  16. Biomass gasification for energy production

    Energy Technology Data Exchange (ETDEWEB)

    Lundberg, H.; Morris, M.; Rensfelt, E. [TPS Termiska Prosesser Ab, Nykoeping (Sweden)

    1997-12-31

    Biomass and waste are becoming increasingly interesting as fuels for efficient and environmentally sound power generation. Circulating fluidized bed (CFB) gasification for biomass and waste has been developed and applied to kilns both in the pulp and paper industry and the cement industry. A demonstration plant in Greve-in- Chianti, Italy includes two 15 MW{sub t}h RDF-fuelled CFB gasifiers of TPS design, the product gas from which is used in a cement kiln or in steam boiler for power generation. For CFB gasification of biomass and waste to reach a wider market, the product gas has to be cleaned effectively so that higher fuel to power efficiencies can be achieved by utilizing power cycles based on engines or gas turbines. TPS has developed both CFB gasification technology and effective secondary stage tar cracking technology. The integrated gasification - gas-cleaning technology is demonstrated today at pilot plant scale. To commercialise the technology, the TPS`s strategy is to first demonstrate the process for relatively clean fuels such as woody biomass and then extend the application to residues from waste recycling. Several demonstration projects are underway to commercialise TPS`s gasification and gas cleaning technology. In UK the ARBRE project developed by ARBRE Energy will construct a gasification plant at Eggborough, North Yorkshire, which will provide gas to a gas turbine and steam turbine generation system, producing 10 MW and exporting 8 Mw of electricity. It has been included in the 1993 tranche of the UK`s Non Fossil Fuel Obligation (NFFO) and has gained financial support from EC`s THERMIE programme as a targeted BIGCC project. (author)

  17. Biomass gasification for energy production

    Energy Technology Data Exchange (ETDEWEB)

    Lundberg, H; Morris, M; Rensfelt, E [TPS Termiska Prosesser Ab, Nykoeping (Sweden)

    1998-12-31

    Biomass and waste are becoming increasingly interesting as fuels for efficient and environmentally sound power generation. Circulating fluidized bed (CFB) gasification for biomass and waste has been developed and applied to kilns both in the pulp and paper industry and the cement industry. A demonstration plant in Greve-in- Chianti, Italy includes two 15 MW{sub t}h RDF-fuelled CFB gasifiers of TPS design, the product gas from which is used in a cement kiln or in steam boiler for power generation. For CFB gasification of biomass and waste to reach a wider market, the product gas has to be cleaned effectively so that higher fuel to power efficiencies can be achieved by utilizing power cycles based on engines or gas turbines. TPS has developed both CFB gasification technology and effective secondary stage tar cracking technology. The integrated gasification - gas-cleaning technology is demonstrated today at pilot plant scale. To commercialise the technology, the TPS`s strategy is to first demonstrate the process for relatively clean fuels such as woody biomass and then extend the application to residues from waste recycling. Several demonstration projects are underway to commercialise TPS`s gasification and gas cleaning technology. In UK the ARBRE project developed by ARBRE Energy will construct a gasification plant at Eggborough, North Yorkshire, which will provide gas to a gas turbine and steam turbine generation system, producing 10 MW and exporting 8 Mw of electricity. It has been included in the 1993 tranche of the UK`s Non Fossil Fuel Obligation (NFFO) and has gained financial support from EC`s THERMIE programme as a targeted BIGCC project. (author)

  18. The potential of net zero energy buildings (NZEBs) concept at design stage for healthcare buildings towards sustainable development

    Science.gov (United States)

    Hazli Abdellah, Roy; Asrul Nasid Masrom, Md; Chen, Goh Kai; Mohamed, Sulzakimin; Omar, Roshartini

    2017-11-01

    The focus on net-zero energy buildings (NZEBs) has been widely analysed and discussed particularly when European Union Parliament are progressively moving towards regulation that promotes the improvement of energy efficiency (EE). Additionally, it also to reduce energy consumption through the recast of the EU Directive on Energy Performance of Buildings (EPBD) in which all new buildings to be “nearly Zero-Energy” Buildings by 2020. Broadly, there is a growing trend to explore the feasibility of net zero energy in healthcare sector as the level energy consumption for healthcare sector is found significantly high. Besides that, healthcare buildings energy consumption also exceeds of many other nondomestic building types, and this shortcoming is still undetermined yet especially for developing countries. This paper aims to review the potential of NZEBs in healthcare buildings by considering its concept in design features. Data are gathered through a comprehensive energy management literature review from previous studies. The review is vital to encourage construction players to increase their awareness, practices, and implementation of NZEBs in healthcare buildings. It suggests that NZEBs concept has a potential to be adapted in healthcare buildings through emphasizing of passive approach as well as the utilization of energy efficiency systems and renewable energy systems in buildings. This paper will provide a basis knowledge for construction key players mainly architects to promote NZEBs concept at design stage for healthcare buildings development.

  19. Net Gain

    International Development Research Centre (IDRC) Digital Library (Canada)

    Describing the effect of tax incentives for import, production, and sale of nets and insecticides; and ..... So far, China is the only country where a system for the routine treatment of ...... 1993), and the trials in Ecuador and Peru (Kroeger et al.

  20. Energy efficient selective reforming of hydrocarbons. ERA-NET Bioenergy. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Rodin, J.

    2010-07-15

    The research project 'Energy efficient selective reforming of hydrocarbons', funded by the Swedish and Energinet.dk Agency has now reached its end. The report is an overview of the work. Details of the work within the different areas can be found in the reports from each part. In this project, an innovative method for tar removal and reformation of hydrocarbons was investigated: Chemical Looping Reforming (CLR). This gas treatment has the potential to be economically competitive, reliable and environmentally friendly (due to higher energy efficiency, amongst others). The aim of the CLR is to 1) eliminate downstream problems with tar 2) simplify the energy recovery from the hot product gas 3) selectively save lighter hydrocarbons for the production of synthetic natural gas (SNG). A guarantor for the outcome of the project is the engagement of Goeteborg Energi, which has a commitment to build a 20 MW output SNG plant by 2012. DTU (Danish Technical University) is responsible for carrying out the laboratorial part, where different oxygen carriers for the CLR have been considering their capability of selectively reforming hydrocarbons. The conclusion was that, of the four carriers tested, the Mn and Ni40 was the most promising. CUT (Chalmers University of Technology) has installed a 600 W CLR unit connected to a slipstream from the gasifier. During the firing season 2010 the CLR has been tested with raw gas for 36 hours and the results so far show that the equipment works as intended and that it can reduce the amount of tars substantially. GE (Goeteborg Energi AB) together with SEP (Scandinavian Energy Project AB) and CUT have studied the integration of a methane production plant to an existing boiler. The main focus of the study has been the gasifier and the CLR. The integration of a 100 MW methane production plant is estimated to cost 1.3-2.4 billion SEK. The different work packages have altogether shown that a CLR is a possible solution to the tar problem

  1. Energy use in apple production in the Esfahan province of Iran ...

    African Journals Online (AJOL)

    The total energy requirement under apple farming was 36,135.16 MJ ha-1, whereas 46.2, 25 and 15.8% was consumed due to chemicals, fuel and manure fertiliser, respectively. Renewable energy was 23.6% of total energy input. The input-output ratio, productivities, specific and net energy gain were 1.17, 0.49 kg MJ-1, ...

  2. Net primary production and canopy nitrogen in a temperate forest landscape: an analysis using imaging spectroscopy, modeling and field data

    Science.gov (United States)

    Scott V. Ollinger; Marie-Louise Smith

    2005-01-01

    Understanding spatial patterns of net primary production (NPP) is central to the study of terrestrial ecosystems, but efforts are frequently hampered by a lack of spatial information regarding factors such as nitrogen availability and site history. Here, we examined the degree to which canopy nitrogen can serve as an indicator of patterns of NPP at the Bartlett...

  3. Net ecosystem productivity and its environmental controls in a mature Scots pine stand in north-western Poland

    Czech Academy of Sciences Publication Activity Database

    Ziemblinska, K.; Urbaniak, M.; Chojnicki, B. H.; Black, T. A.; Niu, S.; Olejnik, Janusz

    2016-01-01

    Roč. 228, nov (2016), s. 60-72 ISSN 0168-1923 Institutional support: RVO:67179843 Keywords : Scots pine * eddy covariance * environmental controls * net ecosystem productivity * southern Finland Subject RIV: EH - Ecology, Behaviour Impact factor: 3.887, year: 2016

  4. Simulation of Net Primary Productivity in Mongolia Using CASA Model, During 2000-2004

    Directory of Open Access Journals (Sweden)

    Narangarav Dugarsuren

    2016-12-01

    Full Text Available Vegetation net primary productivity (NPP is always used as an indicator of carbon cycling in terrestrial ecosystems at landscape and regional scales. Based on the CASA model, we analyzed the spatiotemporal pattern of growing season NPP from 2000 to 2004 using MODIS/NDVI and its relationship with precipitation. The result shows that the annual NPP in Mongolia has a tendency to slightly decrease from 61.13 in 2000 to 60 gC/m2 /yr in 2004, with an annual mean decrement of -0.259 gC/ m2 /yr. However, annual and inter-annual NPP trends showed spatial and temporal heterogeneity. NPP in forest and grassland has decreased with an average annual decrement of -1.03 (r2=0.262 and -0.49 (r2=0.324, meanwhile NPP in desert steppe and desert has increased with the annual average increment of 0.4327 (r2=0.322 and 0.2401 (r2=0.283, respectively. The correlation coeffi cient showed that mean growing season NPP in grassland and desert steppe were closely correlated with precipitation than forest and desert.

  5. Responses of Terrestrial Ecosystems’ Net Primary Productivity to Future Regional Climate Change in China

    Science.gov (United States)

    Zhao, Dongsheng; Wu, Shaohong; Yin, Yunhe

    2013-01-01

    The impact of regional climate change on net primary productivity (NPP) is an important aspect in the study of ecosystems’ response to global climate change. China’s ecosystems are very sensitive to climate change owing to the influence of the East Asian monsoon. The Lund–Potsdam–Jena Dynamic Global Vegetation Model for China (LPJ-CN), a global dynamical vegetation model developed for China’s terrestrial ecosystems, was applied in this study to simulate the NPP changes affected by future climate change. As the LPJ-CN model is based on natural vegetation, the simulation in this study did not consider the influence of anthropogenic activities. Results suggest that future climate change would have adverse effects on natural ecosystems, with NPP tending to decrease in eastern China, particularly in the temperate and warm temperate regions. NPP would increase in western China, with a concentration in the Tibetan Plateau and the northwest arid regions. The increasing trend in NPP in western China and the decreasing trend in eastern China would be further enhanced by the warming climate. The spatial distribution of NPP, which declines from the southeast coast to the northwest inland, would have minimal variation under scenarios of climate change. PMID:23593325

  6. Responses of terrestrial ecosystems' net primary productivity to future regional climate change in China.

    Science.gov (United States)

    Zhao, Dongsheng; Wu, Shaohong; Yin, Yunhe

    2013-01-01

    The impact of regional climate change on net primary productivity (NPP) is an important aspect in the study of ecosystems' response to global climate change. China's ecosystems are very sensitive to climate change owing to the influence of the East Asian monsoon. The Lund-Potsdam-Jena Dynamic Global Vegetation Model for China (LPJ-CN), a global dynamical vegetation model developed for China's terrestrial ecosystems, was applied in this study to simulate the NPP changes affected by future climate change. As the LPJ-CN model is based on natural vegetation, the simulation in this study did not consider the influence of anthropogenic activities. Results suggest that future climate change would have adverse effects on natural ecosystems, with NPP tending to decrease in eastern China, particularly in the temperate and warm temperate regions. NPP would increase in western China, with a concentration in the Tibetan Plateau and the northwest arid regions. The increasing trend in NPP in western China and the decreasing trend in eastern China would be further enhanced by the warming climate. The spatial distribution of NPP, which declines from the southeast coast to the northwest inland, would have minimal variation under scenarios of climate change.

  7. Nonlinear Variations of Net Primary Productivity and Its Relationship with Climate and Vegetation Phenology, China

    Directory of Open Access Journals (Sweden)

    Jian Yang

    2017-09-01

    Full Text Available Net primary productivity (NPP is an important component of the terrestrial carbon cycle. In this study, NPP was estimated based on two models and Moderate Resolution Imaging Spaectroradiometer (MODIS data. The spatiotemporal patterns of NPP and the correlations with climate factors and vegetation phenology were then analyzed. Our results showed that NPP derived from MODIS performed well in China. Spatially, NPP decreased from the southeast toward the northwest. Temporally, NPP showed a nonlinear increasing trend at a national scale, but the magnitude became slow after 2004. At a regional scale, NPP in Northern China and the Tibetan Plateau showed a nonlinear increasing trend, while the NPP decreased in most areas of Southern China. The decreases in NPP were more than offset by the increases. At the biome level, all vegetation types displayed an increasing trend, except for shrub and evergreen broad forests (EBF. Moreover, a turning point year occurred for all vegetation types, except for EBF. Generally, climatic factors and Length of Season were all positively correlated with the NPP, while the relationships were much more diverse at a regional level. The direct effect of solar radiation on the NPP was larger (0.31 than precipitation (0.25 and temperature (0.07. Our results indicated that China could mitigate climate warming at a regional and/or global scale to some extent during the time period of 2001–2014.

  8. Responses of terrestrial ecosystems' net primary productivity to future regional climate change in China.

    Directory of Open Access Journals (Sweden)

    Dongsheng Zhao

    Full Text Available The impact of regional climate change on net primary productivity (NPP is an important aspect in the study of ecosystems' response to global climate change. China's ecosystems are very sensitive to climate change owing to the influence of the East Asian monsoon. The Lund-Potsdam-Jena Dynamic Global Vegetation Model for China (LPJ-CN, a global dynamical vegetation model developed for China's terrestrial ecosystems, was applied in this study to simulate the NPP changes affected by future climate change. As the LPJ-CN model is based on natural vegetation, the simulation in this study did not consider the influence of anthropogenic activities. Results suggest that future climate change would have adverse effects on natural ecosystems, with NPP tending to decrease in eastern China, particularly in the temperate and warm temperate regions. NPP would increase in western China, with a concentration in the Tibetan Plateau and the northwest arid regions. The increasing trend in NPP in western China and the decreasing trend in eastern China would be further enhanced by the warming climate. The spatial distribution of NPP, which declines from the southeast coast to the northwest inland, would have minimal variation under scenarios of climate change.

  9. [Variation trends of natural vegetation net primary productivity in China under climate change scenario].

    Science.gov (United States)

    Zhao, Dong-sheng; Wu, Shao-hong; Yin, Yun-he

    2011-04-01

    Based on the widely used Lund-Potsdam-Jena Dynamic Global Vegetation Model (LPJ) for climate change study, and according to the features of natural environment in China, the operation mechanism of the model was adjusted, and the parameters were modified. With the modified LPJ model and taking 1961-1990 as baseline period, the responses of natural vegetation net primary productivity (NPP) in China to climate change in 1991-2080 were simulated under the Special Report on Emissions Scenarios (SRES) B2 scenario. In 1961-1990, the total NPP of natural vegetation in China was about 3.06 Pg C a(-1); in 1961-2080, the total NPP showed a fluctuant decreasing trend, with an accelerated decreasing rate. Under the condition of slight precipitation change, the increase of mean air temperature would have definite adverse impact on the NPP. Spatially, the NPP decreased from southeast coast to northwest inland, and this pattern would have less variation under climate change. In eastern China with higher NPP, especially in Northeast China, east of North China, and Loess Plateau, the NPP would mainly have a decreasing trend; while in western China with lower NPP, especially in the Tibetan Plateau and Tarim Basin, the NPP would be increased. With the intensive climate change, such a variation trend of NPP would be more obvious.

  10. Net community production and calcification from 7 years of NOAA Station Papa Mooring measurements

    Science.gov (United States)

    Fassbender, Andrea J.; Sabine, Christopher L.; Cronin, Meghan F.

    2016-02-01

    Seven years of near-continuous observations from the Ocean Station Papa (OSP) surface mooring were used to evaluate drivers of marine carbon cycling in the eastern subarctic Pacific. Processes contributing to mixed layer carbon inventory changes throughout each deployment year were quantitatively assessed using a time-dependent mass balance approach in which total alkalinity and dissolved inorganic carbon were used as tracers. By using two mixed layer carbon tracers, it was possible to isolate the influences of net community production (NCP) and calcification. Our results indicate that the annual NCP at OSP is 2 ± 1 mol C m-2 yr-1 and the annual calcification is 0.3 ± 0.3 mol C m-2 yr-1. Piecing together evidence for potentially significant dissolved organic carbon cycling in this region, we estimate a particulate inorganic carbon to particulate organic carbon ratio between 0.15 and 0.25. This is at least double the global average, adding to the growing evidence that calcifying organisms play an important role in carbon export at this location. These results, coupled with significant seasonality in the NCP, suggest that carbon cycling near OSP may be more complex than previously thought and highlight the importance of continuous observations for robust assessments of biogeochemical cycling.

  11. Water consumption in artificial desert oasis based on net primary productivity

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Analysis of the water consumption is the basis for water allocation in oasis. However, the method of estimating oasis water consumption remains a great challenge. Based on net primary productivity (NPP) and the transpiration coefficient, a vegetation water consumption model was developed to estimate the water consumption in desert oasis in ERDAS environment. Our results demonstrated that the ecosystem in the middle reaches of the Heihe oasis consumed water of 18.41×108-21.9×108 m3 for irrigation. Without taking precipitation into account, the water consumption in farmland accounted for 77.1%-77.8% (or about 13.97×108-16.84×108 m3) of the oasis vegetation water consumption and in the farmland protection system accounting for 22%. The growing period precipitation in desert environments is about 7.02×108 m3, and the total annual precipitation is about 8.29×108 m3. The modeled water consumption of desert vegetation, however, is about 4.57×108 m3, equivalent to only 65% of the growing period precipitation or 55% of the total annual precipitation. The modeled value equals to the cumulative precipitation of greater than 5 mm, which is defined as the effective precipitation in arid desert.

  12. Estimating Green Net National Product for Puerto Rico: An Economic Measure of Sustainability

    Science.gov (United States)

    Wu, Shanshan; Heberling, Matthew T.

    2016-04-01

    This paper presents the data sources and methodology used to estimate Green Net National Product (GNNP), an economic metric of sustainability, for Puerto Rico. Using the change in GNNP as a one-sided test of weak sustainability (i.e., positive growth in GNNP is not enough to show the economy is sustainable), we measure the movement away from sustainability by examining the change in GNNP from 1993 to 2009. In order to calculate GNNP, we require both economic and natural capital data, but limited data for Puerto Rico require a number of simplifying assumptions. Based on the environmental challenges faced by Puerto Rico, we include damages from air emissions and solid waste, the storm protection value of mangroves and the value of extracting crushed stone as components in the depreciation of natural capital. Our estimate of GNNP also includes the value of time, which captures the effects of technological progress. The results show that GNNP had an increasing trend over the 17 years studied with two periods of negative growth (2004-2006 and 2007-2008). Our additional analysis suggests that the negative growth in 2004-2006 was possibly due to a temporary economic downturn. However, the negative growth in 2007-2008 was likely from the decline in the value of time, suggesting the island of Puerto Rico was moving away from sustainability during this time.

  13. Net primary production of forest-forming species in climatic gradients of Eurasia

    Directory of Open Access Journals (Sweden)

    V. A. Usoltsev

    2018-04-01

    Full Text Available When using biomass and net primary production (NPP databases compiled by the authors for 6 forest-forming species in a number of 6694 and 2192 sample plots correspondingly, a system of regression models of their NPP is designed and some species-specific regularities of NPP distribution in two climatic gradients (natural zonality and climate continentality are stated. It is found that according to a zonal gradient, aboveground and total NPP in 2-needled pine and spruce-fir forests are monotonically increasing in the direction from the northern to the southern tip of the continent, while larch and birch have the maximum in the southern moderate, and aspen and poplar – in the northern moderate zone, but oak forests do not show any significant pattern. Within a single zonal belt, the aboveground and total NPP of coniferous and deciduous are monotonically decreasing in direction from the Atlantic and Pacific coasts to the continentality pole in Yakutia. The understory NPP of all the species, except oak, monotonically increase towards the subequatorial zone. For oak forests, any clear regularity is not revealed. Within a single zonal belt, when approaching continentality pole, Pinus and Quercus NPP monotonically decreases and in other species, increases. Species-specific patterns in changing the relative indices of NPP (forest stand underground NPP to aboveground one and forest understory NPP to total forest stand one in gradients of the natural zonality and climate continentality are established.

  14. Estimating Green Net National Product for Puerto Rico: An Economic Measure of Sustainability.

    Science.gov (United States)

    Wu, Shanshan; Heberling, Matthew T

    2016-04-01

    This paper presents the data sources and methodology used to estimate Green Net National Product (GNNP), an economic metric of sustainability, for Puerto Rico. Using the change in GNNP as a one-sided test of weak sustainability (i.e., positive growth in GNNP is not enough to show the economy is sustainable), we measure the movement away from sustainability by examining the change in GNNP from 1993 to 2009. In order to calculate GNNP, we require both economic and natural capital data, but limited data for Puerto Rico require a number of simplifying assumptions. Based on the environmental challenges faced by Puerto Rico, we include damages from air emissions and solid waste, the storm protection value of mangroves and the value of extracting crushed stone as components in the depreciation of natural capital. Our estimate of GNNP also includes the value of time, which captures the effects of technological progress. The results show that GNNP had an increasing trend over the 17 years studied with two periods of negative growth (2004-2006 and 2007-2008). Our additional analysis suggests that the negative growth in 2004-2006 was possibly due to a temporary economic downturn. However, the negative growth in 2007-2008 was likely from the decline in the value of time, suggesting the island of Puerto Rico was moving away from sustainability during this time.

  15. Global Human Appropriation of Net Primary Production and Associated Resource Decoupling: 2010-2050.

    Science.gov (United States)

    Zhou, Chuanbin; Elshkaki, Ayman; Graedel, T E

    2018-02-06

    Human appropriation of net primary production (HANPP) methodology has previously been developed to assess the intensity of anthropogenic extraction of biomass resources. However, there is limited analysis concerning future trends of HANPP. Here we present four scenarios for global biomass demand and HANPP harv (the most key component of HANPP) from 2010 to 2050 by incorporating data on expanded historical drivers and disaggregated biomass demand (food, wood material, and fuelwood). The results show that the biomass demand has the lowest value in the equitability world scenario (an egalitarian vision) and the highest value in the security foremost scenario (an isolationist vision). The biomass demand for food and materials increases over time, while fuelwood demand decreases over time. Global HANPP harv rises to between 8.5 and 10.1 Pg C/yr in 2050 in the four scenarios, 14-35% above its value in 2010, and some 50% of HANPP harv is calculated to be crop residues, wood residues, and food losses in the future. HANPP harv in developing regions (Asia, Africa, and Latin America) increases faster than that in more-developed regions (North America and Europe), due to urbanization, population growth, and increasing income. Decoupling of HANPP harv and socioeconomic development is also discussed in this work.

  16. Comparing MODIS Net Primary Production Estimates with Terrestrial National Forest Inventory Data in Austria

    Directory of Open Access Journals (Sweden)

    Mathias Neumann

    2015-04-01

    Full Text Available The mission of this study is to compare Net Primary Productivity (NPP estimates using (i forest inventory data and (ii spatio-temporally continuous MODIS (MODerate resolution Imaging Spectroradiometer remote sensing data for Austria. While forest inventories assess the change in forest growth based on repeated individual tree measurements (DBH, height etc., the MODIS NPP estimates are based on ecophysiological processes such as photosynthesis, respiration and carbon allocation. We obtained repeated national forest inventory data from Austria, calculated a “ground-based” NPP estimate and compared the results with “space-based” MODIS NPP estimates using different daily climate data. The MODIS NPP estimates using local Austrian climate data exhibited better compliance with the forest inventory driven NPP estimates than the MODIS NPP predictions using global climate data sets. Stand density plays a key role in addressing the differences between MODIS driven NPP estimates versus terrestrial driven inventory NPP estimates. After addressing stand density, both results are comparable across different scales. As forest management changes stand density, these findings suggest that management issues are important in understanding the observed discrepancies between MODIS and terrestrial NPP.

  17. Estimated net endogenous acid production and serum bicarbonate in African Americans with chronic kidney disease.

    Science.gov (United States)

    Scialla, Julia J; Appel, Lawrence J; Astor, Brad C; Miller, Edgar R; Beddhu, Srinivasan; Woodward, Mark; Parekh, Rulan S; Anderson, Cheryl A M

    2011-07-01

    Metabolic acidosis may contribute to morbidity and disease progression in patients with chronic kidney disease (CKD). The ratio of dietary protein, the major source of nonvolatile acid, to dietary potassium, which is naturally bound to alkali precursors, can be used to estimate net endogenous acid production (NEAP). We tested the association between estimated NEAP and serum bicarbonate in patients with CKD. NEAP was estimated among 462 African American adults with hypertensive CKD using published equations: NEAP (mEq/d) = -10.2 + 54.5 (protein [g/d]/potassium [mEq/d]). Dietary protein and potassium intake were estimated from 24-hour urinary excretion of urea nitrogen and potassium, respectively. All of the eligible measurements during follow-up were modeled using generalized linear regression clustered by participant and adjusted for demographics, 24-hour urinary sodium, kidney function, and selected medications. Higher NEAP was associated with lower serum bicarbonate in a graded fashion (P trend patients with stage 4/5 CKD (-2.43 mEq/L, P disease (-0.77 mEq/L, P = 0.01; P-interaction = 0.02). Reducing NEAP, through reduction of dietary protein and increased intake of fruits and vegetables, may prevent metabolic acidosis in patients with CKD.

  18. Effects of climate warming on net primary productivity in China during 1961-2010.

    Science.gov (United States)

    Gu, Fengxue; Zhang, Yuandong; Huang, Mei; Tao, Bo; Guo, Rui; Yan, Changrong

    2017-09-01

    The response of ecosystems to different magnitudes of climate warming and corresponding precipitation changes during the last few decades may provide an important reference for predicting the magnitude and trajectory of net primary productivity (NPP) in the future. In this study, a process-based ecosystem model, Carbon Exchange between Vegetation, Soil and Atmosphere (CEVSA), was used to investigate the response of NPP to warming at both national and subregional scales during 1961-2010. The results suggest that a 1.3°C increase in temperature stimulated the positive changing trend in NPP at national scale during the past 50 years. Regardless of the magnitude of temperature increase, warming enhanced the increase in NPP; however, the positive trend of NPP decreased when warming exceeded 2°C. The largest increase in NPP was found in regions where temperature increased by 1-2°C, and this rate of increase also contributed the most to the total increase in NPP in China's terrestrial ecosystems. Decreasing precipitation depressed the positive trend in NPP that was stimulated by warming. In northern China, warming depressed the increasing trend of NPP and warming that was accompanied by decreasing precipitation led to negative changing trends in NPP in large parts of northern China, especially when warming exceeded 2°C. However, warming stimulated the increase in NPP until warming was greater than 2°C, and decreased precipitation helped to increase the NPP in southern China.

  19. Assessing sulfate and carbon controls on net methylmercury production in peatlands: An in situ mesocosm approach

    Energy Technology Data Exchange (ETDEWEB)

    Mitchell, Carl P.J. [Department of Geography, University of Toronto at Mississauga, 3359 Mississauga Road North, Mississauga, Ontario L5L 1C6 (Canada)], E-mail: mitchellc@si.edu; Branfireun, Brian A. [Department of Geography, University of Toronto at Mississauga, 3359 Mississauga Road North, Mississauga, Ontario L5L 1C6 (Canada); Kolka, Randall K. [Northern Research Station, US Department of Agriculture Forest Service, 1831 Highway 169 East, Grand Rapids, MN 55744 (United States)

    2008-03-15

    The transformation of atmospherically deposited inorganic Hg to the toxic, organic form methylmercury (MeHg) is of serious ecological concern because MeHg accumulates in aquatic biota, including fish. Research has shown that the Hg methylation reaction is dependent on the availability of SO{sub 4} (as an electron acceptor) because SO{sub 4}-reducing bacteria (SRB) mediate the biotic methylation of Hg. Much less research has investigated the possible organic C limitations to Hg methylation (i.e. from the perspective of the electron donor). Although peatlands are long-term stores of organic C, the C derived from peatland vegetation is of questionable microbial lability. This research investigated how both SO{sub 4} and organic C control net MeHg production using a controlled factorial addition design in 44 in situ peatland mesocosms. Two levels of SO{sub 4} addition and energetic-equivalent additions (i.e. same number of electrons) of a number of organic C sources were used including glucose, acetate, lactate, coniferous litter leachate, and deciduous litter leachate. This study supports previous research demonstrating the stimulation of MeHg production from SO{sub 4} input alone ({approx}200 pg/L/day). None of the additions of organic C alone resulted in significant MeHg production. The combined addition of SO{sub 4} and some organic C sources resulted in considerably more MeHg production ({approx}500 pg/L/day) than did the addition of SO{sub 4} alone, demonstrating that the highest levels of MeHg production can be expected only where fluxes of both SO{sub 4} and organic C are delivered concurrently. When compared to a number of pore water samples taken from two nearby peatlands, MeHg concentrations resulting from the combined addition of SO{sub 4} and organic C in this study were similar to MeHg 'hot spots' found near the upland-peatland interface. The formation of MeHg 'hot spots' at the upland-peatland interface may be dependent on concurrent

  20. Assessing sulfate and carbon controls on net methylmercury production in peatlands: An in situ mesocosm approach

    International Nuclear Information System (INIS)

    Mitchell, Carl P.J.; Branfireun, Brian A.; Kolka, Randall K.

    2008-01-01

    The transformation of atmospherically deposited inorganic Hg to the toxic, organic form methylmercury (MeHg) is of serious ecological concern because MeHg accumulates in aquatic biota, including fish. Research has shown that the Hg methylation reaction is dependent on the availability of SO 4 (as an electron acceptor) because SO 4 -reducing bacteria (SRB) mediate the biotic methylation of Hg. Much less research has investigated the possible organic C limitations to Hg methylation (i.e. from the perspective of the electron donor). Although peatlands are long-term stores of organic C, the C derived from peatland vegetation is of questionable microbial lability. This research investigated how both SO 4 and organic C control net MeHg production using a controlled factorial addition design in 44 in situ peatland mesocosms. Two levels of SO 4 addition and energetic-equivalent additions (i.e. same number of electrons) of a number of organic C sources were used including glucose, acetate, lactate, coniferous litter leachate, and deciduous litter leachate. This study supports previous research demonstrating the stimulation of MeHg production from SO 4 input alone (∼200 pg/L/day). None of the additions of organic C alone resulted in significant MeHg production. The combined addition of SO 4 and some organic C sources resulted in considerably more MeHg production (∼500 pg/L/day) than did the addition of SO 4 alone, demonstrating that the highest levels of MeHg production can be expected only where fluxes of both SO 4 and organic C are delivered concurrently. When compared to a number of pore water samples taken from two nearby peatlands, MeHg concentrations resulting from the combined addition of SO 4 and organic C in this study were similar to MeHg 'hot spots' found near the upland-peatland interface. The formation of MeHg 'hot spots' at the upland-peatland interface may be dependent on concurrent inputs of SO 4 and organic C in runoff from the adjacent upland hillslopes

  1. Seasonal distribution of dissolved inorganic carbon and net community production on the Bering Sea shelf

    Directory of Open Access Journals (Sweden)

    J. T. Mathis

    2010-05-01

    Full Text Available In order to assess the current state of net community production (NCP in the southeastern Bering Sea, we measured the spatio-temporal distribution and controls on dissolved inorganic carbon (DIC concentrations in spring and summer of 2008 across six shelf domains defined by differing biogeochemical characteristics. DIC concentrations were tightly coupled to salinity in spring and ranged from ~1900 μmoles kg−1 over the inner shelf to ~2400 μmoles kg−1 in the deeper waters of the Bering Sea. In summer, DIC concentrations were lower due to dilution from sea ice melt, terrestrial inputs, and primary production. Concentrations were found to be as low ~1800 μmoles kg−1 over the inner shelf. We found that DIC concentrations were drawn down 30–150 μmoles kg−1 in the upper 30 m of the water column due to primary production and calcium carbonate formation between the spring and summer occupations. Using the seasonal drawdown of DIC, estimated rates of NCP on the inner, middle, and outer shelf averaged 28 ± 9 mmoles C m−2 d−1. However, higher rates of NCP (40–47 mmoles C m−2 d−1 were observed in the "Green Belt" where the greatest confluence of nutrient-rich basin water and iron-rich shelf water occurs. We estimated that in 2008, total NCP across the shelf was on the order of ~96 Tg C yr−1. Due to the paucity of consistent, comparable productivity data, it is impossible at this time to quantify whether the system is becoming more or less productive. However, as changing climate continues to modify the character of the Bering Sea, we have shown that NCP can be an important indicator of how the ecosystem is functioning.

  2. Improved netting

    International Nuclear Information System (INIS)

    Bramley, A.; Clabburn, R.J.T.

    1976-01-01

    A method is described for producing netting composed of longitudinal and transverse threads of irradiation cross linked thermoplastic material, the threads being joined together at their crossings by moulded masses of cross linked thermoplastic material. The thread may be formed of polyethylene filaments, subjected to a radiation dose of 15 to 25 MR. The moulding can be conducted at 245 0 to 260 0 C or higher. The product is claimed to be an improved quality of netting, with bonds of increased strength between crossing threads. (U.K.)

  3. Annual Net Ecosystem Productivity of Wetlands: A Comparison of Automated and Manual Chamber Methods

    Science.gov (United States)

    Burrows, E. H.; Bubier, J. L.; Mosedale, A.; Crill, P. M.

    2001-05-01

    Net Ecosystem Exchange (NEE) of carbon dioxide (CO2) was measured in a minerotrophic poor fen in southeastern New Hampshire during the 2000 growing season using two types of chamber methods. Instantaneous CO2 flux was measured with transparent lexan and teflon static climate controlled chambers by calculating the change in headspace CO2 concentration in the chamber over time. Once per week the flux was sampled from ten manually operated chambers using a LI-COR 6200 portable photosynthesis system, which included a LI-6250 infrared gas analyzer, connected to the chambers. Ten automated chambers were installed in May of 2000, sampling CO2 flux every three hours over the diurnal cycle using a LI-COR 6262 infrared gas analyzer. The chambers and collars were placed throughout the fen in order to sample the range of plant communities. The manual sampling was done during the middle of the day, but the rate of photosynthesis changes depending on the amount of photosynthetically active radiation (PAR). In order to simulate varying light levels, shrouds blocking different amounts of light were placed over each manual chamber. An opaque shroud was used to measure respiration. NEE ranged from -13.0 to 12.5 μ mol CO2/m2/s in the manual chambers and -16.2 to 11.8 μ mol CO2/m2/s in the automated chambers for the mid-summer growing season. Manual respiration fluxes were measured under higher temperature regimes and the response of respiration to temperature will be factored in when comparing the two chamber techniques. Research during the summer of 2001 will also include diurnal measurements. Growing season net ecosystem productivity (NEP) will be estimated and compared for the two chamber systems. Several models will be used to estimate the flux when the manual chambers were not being sampled. The models will be based on biomass and dominant species in each chamber, and various environmental factors including water table, pH, relative humidity, PAR, air and peat temperature

  4. Net ecosystem production in a Little Ice Age moraine: the role of plant functional traits

    Science.gov (United States)

    Varolo, E.; Zanotelli, D.; Tagliavini, M.; Zerbe, S.; Montagnani, L.

    2015-07-01

    Current glacier retreat allows vast mountain ranges available for vegetation establishment and growth. Little is known about the effective carbon (C) budget of these new ecosystems and how the presence of different vegetation communities, characterized by their specific physiology and life forms influences C fluxes. In this study, using a comparative analysis of the C fluxes of two contrasting vegetation types, we intend to evaluate if the different physiologies of the main species have an effect on Ecosystem Respiration (Reco), Gross Primary Production (GPP), annual cumulated Net Ecosystem Exchange (NEE), and long-term carbon accumulation in soil. The NEE of two plant communities present on a Little Ice Age moraine in the Matsch glacier forefield (Alps, Italy) was measured over two growing seasons. They are a typical C3 grassland, dominated by Festuca halleri All. and a community dominated by CAM rosettes Sempervivum montanum L. on rocky soils. Using transparent and opaque chambers, we extrapolated the ecophysiological responses to the main environmental drivers and performed the partition of NEE into Reco and GPP. Soil samples were collected from the same site to measure long-term C accumulation in the ecosystem. The two communities showed contrasting GPP but similar Reco patterns and as a result significantly different in NEE. The grassland acted mainly as a carbon sink with a total cumulated value of -46.4 ± 35.5 g C m-2 NEE while the plots dominated by the CAM rosettes acted as a source with 31.9 ± 22.4 g C m-2. In spite of the NEE being different in the two plant communities, soil analysis did not reveal significant differences in carbon accumulation. Grasslands showed 1.76 ± 0.12 kg C m-2, while CAM rosettes showed 2.06 ± 0.23 kg C m-2. This study demonstrates that carbon dynamics of two vegetation communities can be distinct even though the growing environment is similar. The physiological traits of the dominant species determine large differences in

  5. International Clean Energy System Using Hydrogen Conversion (WE-NET). subtask 2. Research study on promotion of international cooperation (standardization of hydrogen energy technology); Suiso riyo kokusai clean energy system gijutsu (WE-NET). subtask 2. Kokusai kyoryoku suishin no tame no chosa kento (suiso energy gijutsu hyojunka ni kansuru chosa kento)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    This paper describes the basic study on standardization of hydrogen energy technology, and the research study on ISO/TC197 in fiscal 1996. As a part of the WE-NET project, the subtask 2 aims at preparation of standards necessary for practical use and promotion. Developmental states in every field of hydrogen energy technologies, current states of domestic/overseas related standards and laws, and needs and issues of standardization were surveyed. In particular, the needs and issues were clarified in relation to existing standards and laws from the viewpoint of specific hydrogen property. ISO/TC197 was established in 1989 for standardization of the systems and equipment for production, storage, transport, measurement and utilization of hydrogen energy. Four working groups are in action for the supply system and tank of liquid hydrogen fuel for automobiles, the container and ship for complex transport of liquid hydrogen, the specifications of hydrogen products for energy, and the hydrogen supply facility for airports. The draft international standards were proposed to the international conference in 1996. 16 refs., 21 figs., 41 tabs.

  6. A Timed Colored Petri Net Simulation-Based Self-Adaptive Collaboration Method for Production-Logistics Systems

    Directory of Open Access Journals (Sweden)

    Zhengang Guo

    2017-03-01

    Full Text Available Complex and customized manufacturing requires a high level of collaboration between production and logistics in a flexible production system. With the widespread use of Internet of Things technology in manufacturing, a great amount of real-time and multi-source manufacturing data and logistics data is created, that can be used to perform production-logistics collaboration. To solve the aforementioned problems, this paper proposes a timed colored Petri net simulation-based self-adaptive collaboration method for Internet of Things-enabled production-logistics systems. The method combines the schedule of token sequences in the timed colored Petri net with real-time status of key production and logistics equipment. The key equipment is made ‘smart’ to actively publish or request logistics tasks. An integrated framework based on a cloud service platform is introduced to provide the basis for self-adaptive collaboration of production-logistics systems. A simulation experiment is conducted by using colored Petri nets (CPN Tools to validate the performance and applicability of the proposed method. Computational experiments demonstrate that the proposed method outperforms the event-driven method in terms of reductions of waiting time, makespan, and electricity consumption. This proposed method is also applicable to other manufacturing systems to implement production-logistics collaboration.

  7. Fine-Root Production in an Amazon Rain Forest: Deep Roots are an Important Component of Net Primary Productivity

    Science.gov (United States)

    Norby, R.; Cordeiro, A. L.; Oblitas, E.; Valverde-Barrantes, O.; Quesada, C. A.

    2017-12-01

    Fine-root production is a significant component of net primary production (NPP), but it is the most difficult of the major components to measure. Data on fine-root production are especially sparse from tropical forests, and therefore the estimates of tropical forest NPP may not be accurate. Many estimates of fine-root production are based on observations in the top 15 or 30 cm of soil, with the implicit assumption that this approach will capture most of the root distribution. We measured fine-root production in a 30-m tall, old-growth, terra firme rain forest near Manaus, Brazil, which is the site for a free-air CO2 enrichment (FACE) experiment. Ten minirhizotrons were installed at a 45 degree angle to a depth of 1.1 meters; the tubes were installed 2 years before any measurements were made to allow the root systems to recover from disturbance. Images were collected biweekly, and measurements of root length per area of minirhizotron window were scaled up to grams of root per unit land area. Scaling up minirhizotron measurments is problematic, but our estimate of fine-root standing crop in the top 15 cm of soil (281 ± 37 g dry matter m-2) compares well with a direct measurement of fine roots in two nearby 15-cm soil cores (290 ± 37 g m-2). Although the largest fraction of the fine-root standing crop was in the upper soil horizons, 44% of the fine-root mass was deeper than 30 cm, and 17% was deeper than 60 cm. Annual fine-root production was 934 ± 234 g dry matter m-2 (453 ± 113 g C m-2), which was 35% of estimated NPP of the forest stand (1281 g C m-2). A previous estimate of NPP of the forest at this site was smaller (1010 g m-2), but that estimate relied on fine-root production measured elsewhere and only in the top 10 or 30 cm of soil; fine roots accounted for 21% of NPP in that analysis. Extending root observations deeper into the soil will improve estimates of the contribution of fine-root production to NPP, which will in turn improve estimates of ecosystem

  8. Creating a Regional MODIS Satellite-Driven Net Primary Production Dataset for European Forests

    Directory of Open Access Journals (Sweden)

    Mathias Neumann

    2016-06-01

    Full Text Available Net primary production (NPP is an important ecological metric for studying forest ecosystems and their carbon sequestration, for assessing the potential supply of food or timber and quantifying the impacts of climate change on ecosystems. The global MODIS NPP dataset using the MOD17 algorithm provides valuable information for monitoring NPP at 1-km resolution. Since coarse-resolution global climate data are used, the global dataset may contain uncertainties for Europe. We used a 1-km daily gridded European climate data set with the MOD17 algorithm to create the regional NPP dataset MODIS EURO. For evaluation of this new dataset, we compare MODIS EURO with terrestrial driven NPP from analyzing and harmonizing forest inventory data (NFI from 196,434 plots in 12 European countries as well as the global MODIS NPP dataset for the years 2000 to 2012. Comparing these three NPP datasets, we found that the global MODIS NPP dataset differs from NFI NPP by 26%, while MODIS EURO only differs by 7%. MODIS EURO also agrees with NFI NPP across scales (from continental, regional to country and gradients (elevation, location, tree age, dominant species, etc.. The agreement is particularly good for elevation, dominant species or tree height. This suggests that using improved climate data allows the MOD17 algorithm to provide realistic NPP estimates for Europe. Local discrepancies between MODIS EURO and NFI NPP can be related to differences in stand density due to forest management and the national carbon estimation methods. With this study, we provide a consistent, temporally continuous and spatially explicit productivity dataset for the years 2000 to 2012 on a 1-km resolution, which can be used to assess climate change impacts on ecosystems or the potential biomass supply of the European forests for an increasing bio-based economy. MODIS EURO data are made freely available at ftp://palantir.boku.ac.at/Public/MODIS_EURO.

  9. Controls of vegetation structure and net primary production in restored grasslands

    Science.gov (United States)

    Munson, Seth M.; Lauenroth, William K.

    2014-01-01

    1. Vegetation structure and net primary production (NPP) are fundamental properties of ecosystems. Understanding how restoration practices following disturbance interact with environmental factors to control these properties can provide insight on how ecosystems recover and guide management efforts. 2. We assessed the relative contribution of environmental and restoration factors in controlling vegetation structure, above- and below-ground investment in production across a chronosequence of semiarid Conservation Reserve Program (CRP) fields recovering from dryland wheat cropping relative to undisturbed grassland. Importantly, we determined the role of plant diversity and how seeding either native or introduced perennial grasses influenced the recovery of vegetation properties. 3. Plant basal cover increased with field age and was highest in CRP fields seeded with native perennial grasses. In contrast, fields seeded with introduced perennial grasses had tall-growing plants with relatively low basal cover. These vegetation structural characteristics interacted with precipitation, but not soil characteristics, to influence above-ground NPP (ANPP). Fields enrolled in the CRP program for >7 years supported twice as much ANPP as undisturbed shortgrass steppe in the first wet year of the study, but all CRP fields converged on a common low amount of ANPP in the following dry year and invested less than half as much as the shortgrass steppe in below-ground biomass. 4. ANPP in CRP fields seeded with native perennial grasses for more than 7 years was positively related to species richness, whereas ANPP in CRP fields seeded with introduced perennial grasses were controlled more by dominant species. 5. Synthesis and applications. Seeding with introduced, instead of native, perennial grasses had a strong direct influence on vegetation structure, including species richness, which indirectly affected NPP through time. However, the effects of restoring either native or introduced

  10. Estimation of net primary productivity using a process-based model in Gansu Province, Northwest China

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Peijuan; Xie, Donghui; Zhou, Yuyu; E, Youhao; Zhu, Qijiang

    2014-01-16

    The ecological structure in the arid and semi-arid region of Northwest China with forest, grassland, agriculture, Gobi, and desert, is complex, vulnerable, and unstable. It is a challenging and sustaining job to keep the ecological structure and improve its ecological function. Net primary productivity (NPP) modeling can help to improve the understanding of the ecosystem, and therefore, improve ecological efficiency. The boreal ecosystem productivity simulator (BEPS) model provides the possibility of NPP modeling in terrestrial ecosystem, but it has some limitations for application in arid and semi-arid regions. In this paper we improve the BEPS model, in terms of its water cycle by adding the processes of infiltration and surface runoff, to be applicable in arid and semi-arid regions. We model the NPP of forest, grass, and crop in Gansu Province as an experimental area in Northwest China in 2003 using the improved BEPS model, parameterized with moderate resolution remote sensing imageries and meteorological data. The modeled NPP using improved BEPS agrees better with the ground measurements in Qilian Mountain than that with original BEPS, with a higher R2 of 0.746 and lower root mean square error (RMSE) of 46.53 gC/m2 compared to R2 of 0.662 and RMSE of 60.19 gC/m2 from original BEPS. The modeled NPP of three vegetation types using improved BEPS show evident differences compared to that using original BEPS, with the highest difference ratio of 9.21% in forest and the lowest value of 4.29% in crop. The difference ratios between different vegetation types lie on the dependence on natural water sources. The modeled NPP in five geographic zones using improved BEPS are higher than those with original BEPS, with higher difference ratio in dry zones and lower value in wet zones.

  11. Analysis and performance assessment of a multigenerational system powered by Organic Rankine Cycle for a net zero energy house

    International Nuclear Information System (INIS)

    Hassoun, Anwar; Dincer, Ibrahim

    2015-01-01

    This paper develops a new Organic Rankine Cycle (ORC) based multigenerational system to meet the demands of a net zero energy building and assesses such a system for an application to a net zero energy house in Lebanon. Solar energy is the prime source for the integrated system to achieve multigeneration to supply electricity, fresh and hot water, seasonal heating and cooling. The study starts by optimizing the power system with and without grid connection. Then, a comprehensive thermodynamic analysis through energy and exergy, and a parametric study to assess the sensitivity and improvements of the overall system are conducted. Furthermore, exergoeconomic analysis and a follow-up optimization study for optimizing the total system cost to the overall system efficiency using genetic algorithm to obtain the optimal design or a set of optimal designs (Pareto Front), are carried out. The present results show that the optimum solar energy system for a total connected load to the house of 90 kWh/day using a combination of ORC, batteries, convertor has a total net present cost of US $52,505.00 (based on the prices in 2013) with a renewable energy fraction of 1. Moreover, the optimization for the same connected load with ORC, batteries and converter configuration with grid connection results in a total net present cost of $50,868.00 (2013) with a renewable energy fraction of 0.992 with 169 kg/yr of CO 2 emissions. In addition, exergoeconomic analysis of the overall system yields a cost of $117,700.00 (2013), and the multi-objective optimization provides the overall exergetic efficiency by 14% at a total system cost increase of $10,500.00 (2013). - Highlights: • To develop a new Organic Rankine Cycle (ORC) based multigenerational system to meet the demands of a net zero energy building. • To perform a comprehensive thermodynamic analysis through energy and exergy approaches. • To apply an exergoeconomic model for exergy-based cost accounting. • To undertake

  12. Energy intensities of food products. Energie-intensiteiten van voedingsmiddelen

    Energy Technology Data Exchange (ETDEWEB)

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

    1993-08-01

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

  13. IEA Energy Technology Essentials: Biofuel Production

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-01-15

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

  14. Assessing the impact of the urbanization process on net primary productivity in China in 1989-2000.

    Science.gov (United States)

    Tian, Guangjin; Qiao, Zhi

    2014-01-01

    Urban development affects the material circulation and energy flow of ecosystems, thereby affecting the Net Primary Productivity (NPP). The loss of NPP due to urban expansion was calculated integrating GLO-PEM with remote sensing and GIS techniques in China during the period of 1989-2000. Using urban expansion and the mean NPP for the different land use types in the fourteen regions, the total loss of NPP was calculated as 0.95 Tg C, which accounted for 0.03% of the national NPP of 1989. The total loss of NPP due to the transformation from cropland to urban land accounted for 91.93%, followed by forest (7.17%) and grassland (0.69%). However, the conversion from unused land, industrial and construction land, and water bodies to urban land resulted in an increase in the NPP. The regions locating in eastern China and middle China had large reductions in the total NPP due to urban expansion. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Modeling of Carbon Sequestration on Eucalyptus Plantation in Brazililian Cerrado Region for Better Characterization of Net Primary Productivity

    Science.gov (United States)

    Echeverri, J. D.; Siqueira, M. B.

    2013-05-01

    Managed Forests have important roles in climate change due to their contribution to CO2 sequestration stored in their biomass, soils and products therefrom. Terrestrial net primary production (NPP, kgC/m2), equal to gross primary production minus autotrophic respiration, represents the carbon available for plant allocation to leaves, stems, roots, defensive compounds, and reproduction and is the basic measure of biological productivity. Tree growth, food production, fossil fuel production, and atmospheric CO2 levels are all strongly controlled by NPP. Accurate quantification of NPP at local to global scales is therefore central topic for carbon cycle researchers, foresters, land and resource managers, and politicians. For recent or current NPP estimates, satellite remote sensing can be used but for future climate scenarios, simulation models are required. There is an increasing trend to displace natural Brazilian Cerrado to Eucalyptus for paper mills and energy conversion from biomass. The objective of this research exercise is to characterize NPP from managed Eucalyptus plantation in the Brazilian Cerrado. The models selected for this study were the 3-PG and Biome-BGC. The selection of these models aims to cover a range of complexity that allow the evaluation of the processes modeled as to its relevance to a best estimate of productivity in eucalyptus forests. 3-PG model is the simplest of the models chosen for this exercise. Its main purpose is to estimate productivity of forests in timber production. The model uses the relationship of quantum efficiency in the transformation of light energy into biomass for vegetative growth calculations in steps in time of one month. Adverse weather conditions are treated with reduction factors applied in the top efficiency. The second model is the Biome-BGC that uses biology and geochemistry principles to estimate leaf-level photosynthesis based on limiting factors such as availability of light and nutrient constraints. The

  16. Transverse energy production at RHIC

    International Nuclear Information System (INIS)

    Sahoo, Raghunath

    2006-01-01

    The quest for understanding of the possible formation and existence of the quark-gluon plasma (Qp), the deconfined phase of quarks and gluons, has been a major area of research in high energy nuclear physics. High energy nuclear collisions at the Relativistic Heavy Ion Collider (RHIC) has opened a new domain for the exploration of strongly interacting matter at very high energy density and temperature

  17. Automation of Presentation Record Production Based on Rich-Media Technology Using SNT Petri Nets Theory

    Directory of Open Access Journals (Sweden)

    Ivo Martiník

    2015-01-01

    Full Text Available Rich-media describes a broad range of digital interactive media that is increasingly used in the Internet and also in the support of education. Last year, a special pilot audiovisual lecture room was built as a part of the MERLINGO (MEdia-rich Repository of LearnING Objects project solution. It contains all the elements of the modern lecture room determined for the implementation of presentation recordings based on the rich-media technologies and their publication online or on-demand featuring the access of all its elements in the automated mode including automatic editing. Property-preserving Petri net process algebras (PPPA were designed for the specification and verification of the Petri net processes. PPPA does not need to verify the composition of the Petri net processes because all their algebraic operators preserve the specified set of the properties. These original PPPA are significantly generalized for the newly introduced class of the SNT Petri process and agent nets in this paper. The PLACE-SUBST and ASYNC-PROC algebraic operators are defined for this class of Petri nets and their chosen properties are proved. The SNT Petri process and agent nets theory were significantly applied at the design, verification, and implementation of the programming system ensuring the pilot audiovisual lecture room functionality.

  18. Ice melt influence on summertime net community production along the Western Antarctic Peninsula

    Science.gov (United States)

    Eveleth, R.; Cassar, N.; Sherrell, R. M.; Ducklow, H.; Meredith, M. P.; Venables, H. J.; Lin, Y.; Li, Z.

    2017-05-01

    The Western Antarctic Peninsula (WAP) is a highly productive marine environment that is undergoing rapid change, with consequences for productivity and total ecosystem carbon cycling. We present continuous underway O2/Ar estimates of net community production (NCPO2Ar) in austral summer 2012, 2013 and 2014 at sub-kilometer horizontal resolution within the Palmer Long-Term Ecological Research (Pal-LTER) grid region of the WAP. Substantial spatial variability is observed with NCPO2Ar ranging from 0 to 790 mmol O2 m-2 d-1 and considerable interannual variability with mean values in the grid region of 54.4±48.5, 44.6±40.5, and 85.6±75.9 mmol O2 m-2 d-1 in 2012, 2013 and 2014 respectively. Based on a strong correlation (r2=0.83) between residence time integrated NCPO2Ar and NCPDIC derived from seasonal DIC drawdown, we find the observed NCPO2Ar spatial and interannual variability to be consistent with the December-January NCPDIC magnitude. Seeking to explain the mechanistic drivers of NCP in the WAP, we observe a linear relationship between NCPO2Ar and meteoric water content derived from δ18O and salinity. This correlation may be due to Fe supply from glacial melt and/or strengthening of stratification and relief of light limitation. Elevated surface Fe availability, as indicated by Fv/Fm and measurements of surface water dissolved Fe and Mn (a rough proxy for recent potential Fe availability), and shallower, more stable mixed layers are present where meteoric water and/or sea ice melt is high near the coast. Light limitation is evident in the WAP when mixed layer depths are greater than 40 m. Additionally we document hotspots of NCP associated with submarine canyons along the WAP. While it is difficult to predict how the physical-biological system might evolve under changing climatic conditions, it is evident that NCP, and potentially carbon flux out of the mixed layer, along the WAP will be sensitive to shifts in meltwater input and timing.

  19. Higher-moment measurements of net-kaon, net-charge and net-proton multiplicity distributions at STAR

    International Nuclear Information System (INIS)

    Sarkar, Amal

    2014-01-01

    In this paper, we report the measurements of the various moments, such as mean, standard deviation (σ), skewness (S) and kurtosis (κ) of the net-kaon, net-charge and net-proton multiplicity distributions at mid-rapidity in Au + Au collisions from √(s NN )=7.7 to 200 GeV with the STAR experiment at RHIC. This work has been done with the aim to locate the critical point on the QCD phase diagram. These moments and their products are related to the thermodynamic susceptibilities of conserved quantities such as net baryon number, net charge, and net strangeness as well as to the correlation length of the system which diverges in an ideal infinite thermodynamic system at the critical point. For a finite system, existing for a finite time, a non-monotonic behavior of these variables would indicate the presence of the critical point. Furthermore, we also present the moment products Sσ, κσ 2 of net-kaon, net-charge and net-proton multiplicity distributions as a function of collision centrality and energy. The energy and the centrality dependence of higher moments and their products have been compared with different models

  20. Promoting greater Federal energy productivity [Final report

    Energy Technology Data Exchange (ETDEWEB)

    Hopkins, Mark; Dudich, Luther

    2003-03-05

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

  1. Performance of free-range chickens reared in production modules enriched with shade net and perches

    Directory of Open Access Journals (Sweden)

    MJB Santos

    2014-03-01

    Full Text Available An experiment was carried out to evaluate the effect of environmental enrichment in a free-range chicken production system on live performance as a function of microclimate, physiological parameters, and performance parameters. Four production modules were divided into four pens with 10 birds each, totaling 60 birds. The following treatments were applied: access to a paddock (TEST, access to a paddock with perches (PER, access to a paddock with artificial shade (SHA, and access to the paddock with perches and artificial shade (PESH. The PESH production module presented the best globe temperature (Tbg,ºC and enthalpy (h, kJ/kg, and thereby, the best thermal environmental conditions, which ensured the longest permanence time of the birds in the paddock. The SHA and PESH modules promoted the lowest respiratory rate and shank and comb temperatures. Live performance was influenced by the presence of environmental enrichment (modules SHA and PESH, with the highest live weight (LW and weight gain (WG and the lowest feed conversion ratio (FCR and metabolizable energy intake (MEI. Parts yield, such as giblets, were not influenced by production modules, except for PESH, which promoted higher offal weight. In general, chickens reared in enriched production modules presented greatest performance and comfort results and were considered close to optimal rearing conditions.

  2. Evaluation of Net Primary Productivity and Carbon Allocation to Different Parts of Corn in Different Tillage and Nutrient Management Systems

    Directory of Open Access Journals (Sweden)

    esmat mohammadi

    2017-09-01

    Full Text Available Evaluation of net primary productivity and carbon allocation to different organs of corn under nutrient management and tillage systems Introduction Agriculture operations produce 10 to 20 percent of greenhouse gases. As a result of conventional operations of agriculture, greenhouse gases have been increased (Osborne et al., 2010. Therefor it is necessary to notice to carbon sequestration to reduce greenhouse gases emissions. In photosynthesis process, plants absorb CO2 and large amounts of organic carbon accumulate in their organs. Biochar is produced of pyrolysis of organic compounds. Biochar is an appropriate compound for improved of soil properties and carbon sequestration (Whitman and Lehmann, 2009; Smith et al., 2010. Conservation tillage has become an important technology in sustainable agriculture due to its benefits. So the aim of this study was to evaluate the effect of nutrient management and tillage systems on net primary production and carbon allocation to different organs of corn in Shahrood. Material and methods This study was conducted at the Shahrood University of Technology research farm. Experiment was done as split plot in randomized complete block design with three replications. Tillage systems with two levels (conventional tillage and minimum tillage were as the main factor and nutrient management in seven levels including (control, chemical fertilizer, manure, biochar, chemical fertilizer + manure, chemical fertilizer + biochar, manure + biochar were considered as sub plot. At the time of maturity of corn, was sampled from its aboveground and belowground biomasses. Carbon content of shoot, seed and root was considered almost 45 percent of yield of each of these biomasses and carbon in root exudates almost 65 percent of carbon in the root. Statistical analysis of the data was performed using SAS program. Comparison of means was conducted with LSD test at the 5% level. Results and discussion Effect of nutrient management was

  3. Characterizing uncertainties in recent trends of global terrestrial net primary production through ensemble modeling

    Science.gov (United States)

    Wang, W.; Hashimoto, H.; Ganguly, S.; Votava, P.; Nemani, R. R.; Myneni, R. B.

    2010-12-01

    Large uncertainties exist in our understanding of the trends and variability in global net primary production (NPP) and its controls. This study attempts to address this question through a multi-model ensemble experiment. In particular, we drive ecosystem models including CASA, LPJ, Biome-BGC, TOPS-BGC, and BEAMS with a long-term climate dataset (i.e., CRU-NCEP) to estimate global NPP from 1901 to 2009 at a spatial resolution of 0.5 x 0.5 degree. We calculate the trends of simulated NPP during different time periods and test their sensitivities to climate variables of solar radiation, air temperature, precipitation, vapor pressure deficit (VPD), and atmospheric CO2 levels. The results indicate a large diversity among the simulated NPP trends over the past 50 years, ranging from nearly no trend to an increasing trend of ~0.1 PgC/yr. Spatial patterns of the NPP generally show positive trends in boreal forests, induced mainly by increasing temperatures in these regions; they also show negative trends in the tropics, although the spatial patterns are more diverse. These diverse trends result from different climatic sensitivities of NPP among the tested models. Depending the ecological processes (e.g., photosynthesis or respiration) a model emphasizes, it can be more or less responsive to changes in solar radiation, temperatures, water, or atmospheric CO2 levels. Overall, these results highlight the limit of current ecosystem models in simulating NPP, which cannot be easily observed. They suggest that the traditional single-model approach is not ideal for characterizing trends and variability in global carbon cycling.

  4. A new framework for evaluating the impacts of drought on net primary productivity of grassland.

    Science.gov (United States)

    Lei, Tianjie; Wu, Jianjun; Li, Xiaohan; Geng, Guangpo; Shao, Changliang; Zhou, Hongkui; Wang, Qianfeng; Liu, Leizhen

    2015-12-01

    This paper presented a valuable framework for evaluating the impacts of droughts (single factor) on grassland ecosystems. This framework was defined as the quantitative magnitude of drought impact that unacceptable short-term and long-term effects on ecosystems may experience relative to the reference standard. Long-term effects on ecosystems may occur relative to the reference standard. Net primary productivity (NPP) was selected as the response indicator of drought to assess the quantitative impact of drought on Inner Mongolia grassland based on the Standardized Precipitation Index (SPI) and BIOME-BGC model. The framework consists of six main steps: 1) clearly defining drought scenarios, such as moderate, severe and extreme drought; 2) selecting an appropriate indicator of drought impact; 3) selecting an appropriate ecosystem model and verifying its capabilities, calibrating the bias and assessing the uncertainty; 4) assigning a level of unacceptable impact of drought on the indicator; 5) determining the response of the indicator to drought and normal weather state under global-change; and 6) investigating the unacceptable impact of drought at different spatial scales. We found NPP losses assessed using the new framework were more sensitive to drought and had higher precision than the long-term average method. Moreover, the total and average losses of NPP are different in different grassland types during the drought years from 1961-2009. NPP loss was significantly increased along a gradient of increasing drought levels. Meanwhile, NPP loss variation under the same drought level was different in different grassland types. The operational framework was particularly suited for integrative assessing the effects of different drought events and long-term droughts at multiple spatial scales, which provided essential insights for sciences and societies that must develop coping strategies for ecosystems for such events. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Climate dependence of the CO2 fertilization effect on terrestrial net primary production

    International Nuclear Information System (INIS)

    Alexandrov, G.A.; Yamagata, Y.; Oikawa, T.

    2003-01-01

    The quantitative formulation of the fertilization effect of CO 2 enrichment on net primary production (NPP) introduced by Keeling and Bacastow in 1970s (known as Keeling's formula) has been recognized as a summary of experimental data and has been used in various assessments of the industrial impact on atmospheric chemistry. Nevertheless, the magnitude of the formula's key coefficient, the so-called growth factor, has remained open to question. Some of the global carbon cycle modelers avoid this question by tuning growth factor and choosing the value that fits the observed course of atmospheric CO 2 changes. However, for mapping terrestrial sinks induced by the CO 2 fertilization effect one needs a geographical pattern of the growth factor rather than its globally averaged value. The earlier approach to this problem involved formulating the climate dependence of the growth factor and the derivation of its global pattern from climatic variables (whose geographical distribution is known). We use a process-based model (TsuBiMo) for this purpose and derive the values of growth factor for major biomes for comparison our approach with the earlier studies. Contrary to the earlier prevailing opinion, TsuBiMo predicts that these values decrease with mean annual temperature (excluding biomes of limited water supply). We attribute this result to the effect of light limitation caused by mutual shading inside a canopy, which was considered earlier as unimportant, and conclude that current hypotheses about CO 2 fertilization effect (and thus projections of the related carbon sink) are very sensitive to the choice of driving forces taken into account

  6. Effects of UVB radiation on net community production in the upper global ocean

    KAUST Repository

    Garcia-Corral, Lara S.

    2016-08-31

    Aim Erosion of the stratospheric ozone layer together with oligotrophication of the subtropical ocean is leading to enhanced exposure to ultraviolet B (UVB) radiation in ocean surface waters. The impact of increased exposure to UVB on planktonic primary producers and heterotrophs is uncertain. Here we test the null hypothesis that net community production (NCP) of plankton communities in surface waters of the tropical and subtropical ocean is not affected by ambient UVB radiation and extend this test to the global ocean, including the polar oceans and the Mediterranean Sea using previous results. Location We conducted experiments with 131 surface communities sampled during a circumnavigation cruise along the tropical and subtropical ocean and combined these results with 89 previous reports encompassing the Atlantic, Pacific, Arctic and Southern Oceans and the Mediterranean Sea. Methods The use of quartz (transparent to UVB radiation) and borosilicate glass materials (opaque to most UVB) for incubations allowed us to compare NCP between communities where UVB is excluded and those receiving natural UVB radiation. Results We found that NCP varies when exposed to natural UVB radiation compared to those where UVB was removed. NCP of autotrophic communities tended to decrease under natural UVB radiation, whereas the NCP of heterotrophic communities tended to increase. However, these variations showed the opposite trend under higher levels of UVB radiation. Main conclusions Our results suggest that earlier estimates of NCP for surface communities, which were hitherto derived using materials blocking UVB radiation were biased, with the direction and magnitude of this bias depending on the metabolic status of the communities and the underwater penetration of UVB radiation.

  7. Net community production at Ocean Station Papa observed with nitrate and oxygen sensors on profiling floats

    Science.gov (United States)

    Plant, Joshua N.; Johnson, Kenneth S.; Sakamoto, Carole M.; Jannasch, Hans W.; Coletti, Luke J.; Riser, Stephen C.; Swift, Dana D.

    2016-06-01

    Six profiling floats equipped with nitrate and oxygen sensors were deployed at Ocean Station P in the Gulf of Alaska. The resulting six calendar years and 10 float years of nitrate and oxygen data were used to determine an average annual cycle for net community production (NCP) in the top 35 m of the water column. NCP became positive in February as soon as the mixing activity in the surface layer began to weaken, but nearly 3 months before the traditionally defined mixed layer began to shoal from its winter time maximum. NCP displayed two maxima, one toward the end of May and another in August with a summertime minimum in June corresponding to the historical peak in mesozooplankton biomass. The average annual NCP was determined to be 1.5 ± 0.6 mol C m-2 yr-1 using nitrate and 1.5 ± 0.7 mol C m-2 yr-1 using oxygen. The results from oxygen data proved to be quite sensitive to the gas exchange model used as well as the accuracy of the oxygen measurement. Gas exchange models optimized for carbon dioxide flux generally ignore transport due to gas exchange through the injection of bubbles, and these models yield NCP values that are two to three time higher than the nitrate-based estimates. If nitrate and oxygen NCP rates are assumed to be related by the Redfield model, we show that the oxygen gas exchange model can be optimized by tuning the exchange terms to reproduce the nitrate NCP annual cycle.

  8. Energy production and reactor efficiency

    International Nuclear Information System (INIS)

    Anon.

    1975-01-01

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

  9. A NetCDF version of the two-dimensional energy balance model based on the full multigrid algorithm

    Directory of Open Access Journals (Sweden)

    Kelin Zhuang

    2017-01-01

    Full Text Available A NetCDF version of the two-dimensional energy balance model based on the full multigrid method in Fortran is introduced for both pedagogical and research purposes. Based on the land–sea–ice distribution, orbital elements, greenhouse gases concentration, and albedo, the code calculates the global seasonal surface temperature. A step-by-step guide with examples is provided for practice.

  10. Well-to-refinery emissions and net-energy analysis of China's crude-oil supply

    Science.gov (United States)

    Masnadi, Mohammad S.; El-Houjeiri, Hassan M.; Schunack, Dominik; Li, Yunpo; Roberts, Samori O.; Przesmitzki, Steven; Brandt, Adam R.; Wang, Michael

    2018-03-01

    Oil is China's second-largest energy source, so it is essential to understand the country's greenhouse gas emissions from crude-oil production. Chinese crude supply is sourced from numerous major global petroleum producers. Here, we use a per-barrel well-to-refinery life-cycle analysis model with data derived from hundreds of public and commercial sources to model the Chinese crude mix and the upstream carbon intensities and energetic productivity of China's crude supply. We generate a carbon-denominated supply curve representing Chinese crude-oil supply from 146 oilfields in 20 countries. The selected fields are estimated to emit between 1.5 and 46.9 g CO2eq MJ-1 of oil, with volume-weighted average emissions of 8.4 g CO2eq MJ-1. These estimates are higher than some existing databases, illustrating the importance of bottom-up models to support life-cycle analysis databases. This study provides quantitative insight into China's energy policy and the economic and environmental implications of China's oil consumption.

  11. The digestible energy, metabolizable energy, and net energy content of dietary fat sources in thirteen- and fifty-kilogram pigs.

    Science.gov (United States)

    Kellner, T A; Patience, J F

    2017-09-01

    The objective was to determine the energy concentration of a diverse array of dietary fat sources and, from these data, develop regression equations that explain differences based on chemical composition. A total of 120 Genetiporc 6.0 × Genetiporc F25 (PIC, Inc., Hendersonville, TN) individually housed barrows were studied for 56 d. These barrows (initial BW of 9.9 ± 0.6 kg) were randomly allotted to 1 of 15 dietary treatments. Each experimental diet included 95% of a corn-soybean meal basal diet plus 5% either corn starch or 1 of 14 dietary fat sources. The 14 dietary fat sources (animal-vegetable blend, canola oil, choice white grease source A, choice white grease source B, coconut oil, corn oil source A, corn oil source B, fish oil, flaxseed oil, palm oil, poultry fat, soybean oil source A, soybean oil source B, and tallow) were selected to provide a diverse and robust range of unsaturated fatty acid:SFA ratios (U:S). Pigs were limit-fed experimental diets from d 0 to 10 and from d 46 to 56, providing a 7-d adaption for fecal collection on d 7 to 10 (13 kg BW) and d 53 to 56 (50 kg BW). At 13 kg BW, the average energy content of the 14 sources was 8.42 Mcal DE/kg, 8.26 Mcal ME/kg, and 7.27 Mcal NE/kg. At 50 kg BW, the average energy content was 8.45 Mcal DE/kg, 8.28 Mcal ME/kg, and 7.29 Mcal NE/kg. At 13 kg BW, the variation of dietary fat DE content was explained by DE (Mcal/kg) = 9.363 + [0.097 × (FFA, %)] - [0.016 × omega-6:omega-3 fatty acids ratio] - [1.240 × (arachidic acid, %)] - [5.054 × (insoluble impurities, %)] + [0.014 × (palmitic acid, %)] ( = 0.008, = 0.82). At 50 kg BW, the variation of dietary fat DE content was explained by DE (Mcal/kg) = 8.357 + [0.189 × U:S] - [0.195 × (FFA, %)] - [6.768 × (behenic acid, %)] + [0.024 × (PUFA, %)] ( = 0.002, = 0.81). In summary, the chemical composition of dietary fat explained a large degree of the variation observed in the energy content of dietary fat sources at both 13 and 50 kg BW.

  12. Decadal-Scale Reduction in Forest Net Ecosystem Production Following Insect Defoliation Contrasts with Short-Term Impacts of Prescribed Fires

    Science.gov (United States)

    Kenneth L. Clark; Heidi J. Renninger; Nicholas Skowronski; Michael Gallagher; Karina V.R.  Schäfer

    2018-01-01

    Understanding processes underlying forest carbon dynamics is essential for accurately predicting the outcomes of non-stand-replacing disturbance in intermediate-age forests. We quantified net ecosystem production (NEP), aboveground net primary production (ANPP), and the dynamics of major carbon (C) pools before and during the decade following invasive insect...

  13. Future supply and demand of net primary production in the Sahel

    Science.gov (United States)

    Sallaba, Florian; Olin, Stefan; Engström, Kerstin; Abdi, Abdulhakim M.; Boke-Olén, Niklas; Lehsten, Veiko; Ardö, Jonas; Seaquist, Jonathan W.

    2017-12-01

    In the 21st century, climate change in combination with increasing demand, mainly from population growth, will exert greater pressure on the ecosystems of the Sahel to supply food and feed resources. The balance between supply and demand, defined as the annual biomass required for human consumption, serves as a key metric for quantifying basic resource shortfalls over broad regions.Here we apply an exploratory modelling framework to analyse the variations in the timing and geography of different NPP (net primary production) supply-demand scenarios, with distinct assumptions determining supply and demand, for the 21st century Sahel. We achieve this by coupling a simple NPP supply model forced with projections from four representative concentration pathways with a global, reduced-complexity demand model driven by socio-economic data and assumptions derived from five shared socio-economic pathways.For the scenario that deviates least from current socio-economic and climate trends, we find that per capita NPP begins to outstrip supply in the 2040s, while by 2050 half the countries in the Sahel experience NPP shortfalls. We also find that despite variations in the timing of the onset of NPP shortfalls, demand cannot consistently be met across the majority of scenarios. Moreover, large between-country variations are shown across the scenarios, in which by the year 2050 some countries consistently experience shortage or surplus, while others shift from surplus to shortage. At the local level (i.e. grid cell), hotspots of total NPP shortfall consistently occur in the same locations across all scenarios but vary in size and magnitude. These hotspots are linked to population density and high demand. For all scenarios, total simulated NPP supply doubles by 2050 but is outpaced by increasing demand due to a combination of population growth and the adoption of diets rich in animal products. Finally, variations in the timing of the onset and end of supply shortfalls stem from

  14. Future supply and demand of net primary production in the Sahel

    Directory of Open Access Journals (Sweden)

    F. Sallaba

    2017-12-01

    Full Text Available In the 21st century, climate change in combination with increasing demand, mainly from population growth, will exert greater pressure on the ecosystems of the Sahel to supply food and feed resources. The balance between supply and demand, defined as the annual biomass required for human consumption, serves as a key metric for quantifying basic resource shortfalls over broad regions.Here we apply an exploratory modelling framework to analyse the variations in the timing and geography of different NPP (net primary production supply–demand scenarios, with distinct assumptions determining supply and demand, for the 21st century Sahel. We achieve this by coupling a simple NPP supply model forced with projections from four representative concentration pathways with a global, reduced-complexity demand model driven by socio-economic data and assumptions derived from five shared socio-economic pathways.For the scenario that deviates least from current socio-economic and climate trends, we find that per capita NPP begins to outstrip supply in the 2040s, while by 2050 half the countries in the Sahel experience NPP shortfalls. We also find that despite variations in the timing of the onset of NPP shortfalls, demand cannot consistently be met across the majority of scenarios. Moreover, large between-country variations are shown across the scenarios, in which by the year 2050 some countries consistently experience shortage or surplus, while others shift from surplus to shortage. At the local level (i.e. grid cell, hotspots of total NPP shortfall consistently occur in the same locations across all scenarios but vary in size and magnitude. These hotspots are linked to population density and high demand. For all scenarios, total simulated NPP supply doubles by 2050 but is outpaced by increasing demand due to a combination of population growth and the adoption of diets rich in animal products. Finally, variations in the timing of the onset and end of supply

  15. Logging disturbance shifts net primary productivity and its allocation in Bornean tropical forests.

    Science.gov (United States)

    Riutta, Terhi; Malhi, Yadvinder; Kho, Lip Khoon; Marthews, Toby R; Huaraca Huasco, Walter; Khoo, MinSheng; Tan, Sylvester; Turner, Edgar; Reynolds, Glen; Both, Sabine; Burslem, David F R P; Teh, Yit Arn; Vairappan, Charles S; Majalap, Noreen; Ewers, Robert M

    2018-01-24

    Tropical forests play a major role in the carbon cycle of the terrestrial biosphere. Recent field studies have provided detailed descriptions of the carbon cycle of mature tropical forests, but logged or secondary forests have received much less attention. Here, we report the first measures of total net primary productivity (NPP) and its allocation along a disturbance gradient from old-growth forests to moderately and heavily logged forests in Malaysian Borneo. We measured the main NPP components (woody, fine root and canopy NPP) in old-growth (n = 6) and logged (n = 5) 1 ha forest plots. Overall, the total NPP did not differ between old-growth and logged forest (13.5 ± 0.5 and 15.7 ± 1.5 Mg C ha -1  year -1 respectively). However, logged forests allocated significantly higher fraction into woody NPP at the expense of the canopy NPP (42% and 48% into woody and canopy NPP, respectively, in old-growth forest vs 66% and 23% in logged forest). When controlling for local stand structure, NPP in logged forest stands was 41% higher, and woody NPP was 150% higher than in old-growth stands with similar basal area, but this was offset by structure effects (higher gap frequency and absence of large trees in logged forest). This pattern was not driven by species turnover: the average woody NPP of all species groups within logged forest (pioneers, nonpioneers, species unique to logged plots and species shared with old-growth plots) was similar. Hence, below a threshold of very heavy disturbance, logged forests can exhibit higher NPP and higher allocation to wood; such shifts in carbon cycling persist for decades after the logging event. Given that the majority of tropical forest biome has experienced some degree of logging, our results demonstrate that logging can cause substantial shifts in carbon production and allocation in tropical forests. © 2018 John Wiley & Sons Ltd.

  16. Design and Evaluation of a Net Zero Energy Low-Income Residential Housing Development in Lafayette, Colorado

    Energy Technology Data Exchange (ETDEWEB)

    Dean, J.; VanGeet, O.; Simkus, S.; Eastment, M.

    2012-03-01

    This report outlines the lessons learned and sub-metered energy performance of an ultra low energy single family ranch home and duplex unit, called the Paradigm Pilot Project and presents the final design recommendations for a 153-unit net zero energy residential development called the Josephine Commons Project. Affordable housing development authorities throughout the United States continually struggle to find the most cost-effective pathway to provide quality, durable, and sustainable housing. The challenge for these authorities is to achieve the mission of delivering affordable housing at the lowest cost per square foot in environments that may be rural, urban, suburban, or within a designated redevelopment district. With the challenges the U.S. faces regarding energy, the environmental impacts of consumer use of fossil fuels and the increased focus on reducing greenhouse gas emissions, housing authorities are pursuing the goal of constructing affordable, energy efficient and sustainable housing at the lowest life-cycle cost of ownership. This report outlines the lessons learned and sub-metered energy performance of an ultra-low-energy single family ranch home and duplex unit, called the Paradigm Pilot Project and presents the final design recommendations for a 153-unit net zero energy residential development called the Josephine Commons Project. In addition to describing the results of the performance monitoring from the pilot project, this paper describes the recommended design process of (1) setting performance goals for energy efficiency and renewable energy on a life-cycle cost basis, (2) using an integrated, whole building design approach, and (3) incorporating systems-built housing, a green jobs training program, and renewable energy technologies into a replicable high performance, low-income housing project development model.

  17. Expected energy production evaluation for photovoltaic systems

    DEFF Research Database (Denmark)

    Ding, Yi; Østergaard, Jacob; Peng, Wang

    2011-01-01

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

  18. Egypt risks to become net importer of energy toward the year 2000 according to the World Bank

    International Nuclear Information System (INIS)

    Anon.

    1994-01-01

    Petroleum exports were about the two-third of the whole goods exports of Egypt in the eighties years, but this part is getting under 50%, because a lower growth of exported volume and because of the reduction of prices. As these kinds of things are continuing during the nineties years and the local petroleum consumption is increasing, Egypt could become a net importer of petroleum products at the end of the century

  19. Investigation of the impact of using thermal mass with the net zero energy town house in Toronto using TRNSYS

    Energy Technology Data Exchange (ETDEWEB)

    Siddiqui, O.; Fung, A.; Tse, H.; Zhang, D. [Ryerson Polytechnic Univ., Toronto, ON (Canada). Dept. of Mechanical and Industrial Engineering

    2008-07-01

    Since buildings in Canada account for 30 per cent of the country's total energy consumption, it has become necessary to find ways to reduce the overall energy use in buildings. Heating and cooling loads in buildings can be effectively reduced by using the thermal mass incorporated into the building envelope, particularly in climates where a large daily temperature fluctuations exist. Thermal mass is defined as any building material that has a high heat storage capacity that can be integrated into the structural fabric of the building to use the passive solar energy for heating or cooling purposes. Concrete slabs, bricks and ceramic blocks are some of the commonly used materials. This study analyzed the impact of using thermal mass with a highly insulated building envelope such as that used in Low Energy or Net Zero housing. In particular, TRNSYS was used to simulate a Net Zero Energy Town House located in Toronto, in which a ground source heat pump was integrated with an infloor radiant heating system. The simulation revealed that for colder climates such as in Canada, thermal mass can replace some of the insulation while still providing excellent results in terms of the reductions in daily indoor temperature fluctuations. The impact of thermal mass during the winter was more significant when compared with summer, possibly because of the unique construction and orientation of the Net Zero Energy House. The optimum thickness of the concrete slab was determined to be 6 inches for the winter season and 4 inches for summer. The optimum location for the thermal mass was found to be right next to the gypsum wallboard that forms the interior part of the wall. 12 refs., 1 tab., 11 figs.

  20. Water and energy link in the cities of the future - achieving net zero carbon and pollution emissions footprint.

    Science.gov (United States)

    Novotny, V

    2011-01-01

    This article discusses the link between water conservation, reclamation, reuse and energy use as related to the goal of achieving the net zero carbon emission footprint in future sustainable cities. It defines sustainable ecocities and outlines quantitatively steps towards the reduction of energy use due to water and used water flows, management and limits in linear and closed loop water/stormwater/wastewater management systems. The three phase water energy nexus diagram may have a minimum inflection point beyond which reduction of water demand may not result in a reduction of energy and carbon emissions. Hence, water conservation is the best alternative solution to water shortages and minimizing the carbon footprint. A marginal water/energy chart is developed and proposed to assist planners in developing future ecocities and retrofitting older communities to achieve sustainability.

  1. Energy assessment of second generation (2G) ethanol production from wheat straw in Indian scenario.

    Science.gov (United States)

    Mishra, Archana; Kumar, Akash; Ghosh, Sanjoy

    2018-03-01

    Impact of second-generation ethanol (2G) use in transportation sector mainly depends upon energy efficiency of entire production process. The objective of present study was to determine energy efficiency of a potential lignocellulosic feedstock; wheat straw and its conversion into cellulosic ethanol in Indian scenario. Energy efficiency was determined by calculating Net energy ratio (NER), i.e. ratio of output energy obtained by ethanol and input energy used in ethanol production. Energy consumption and generation at each step is calculated briefly (11,837.35 MJ/ha during Indian dwarf irrigated variety of wheat crop production and 7.1148 MJ/kg straw during ethanol production stage). Total energy consumption is calculated as 8.2988 MJ/kg straw whereas energy generation from ethanol is 15.082 MJ/kg straw; resulting into NER > 1. Major portion of agricultural energy input is contributed by diesel and fertilisers whereas refining process of wheat straw feedstock to ethanol and by-products require mainly in the form of steam and electricity. On an average, 1671.8 kg water free ethanol, 930 kg lignin rich biomass (for combustion), and 561 kg C5-molasses (for fodder) per hectare are produced. Findings of this study, net energy ratio (1.81) and figure of merit (14.8028 MJ/nil kg carbon) proves wheat straw as highest energy efficient lignocellulosic feedstock for the country.

  2. Net Surface Shortwave Radiation from GOES Imagery—Product Evaluation Using Ground-Based Measurements from SURFRAD

    Directory of Open Access Journals (Sweden)

    Anand K. Inamdar

    2015-08-01

    Full Text Available The Earth’s surface net radiation controls the energy and water exchanges between the Earth’s surface and the atmosphere, and can be derived from satellite observations. The ability to monitor the net surface radiation over large areas at high spatial and temporal resolution is essential for many applications, such as weather forecasting, short-term climate prediction or water resources management. The objective of this paper is to derive the net surface radiation in the shortwave domain at high temporal (half-hourly and spatial resolution (~1 km using visible imagery from Geostationary Operational Environmental Satellite (GOES. The retrieval algorithm represents an adaptation to GOES data of a standard algorithm initially developed for the NASA-operated Clouds and Earth’s Radiant Energy System (CERES scanner. The methodology relies on: (1 the estimation of top of atmosphere shortwave radiation from GOES spectral measurements; and (2 the calculation of net surface shortwave (SW radiation accounting for atmospheric effects. Comparison of GOES-retrieved net surface shortwave radiation with ground-measurements at the National Oceanic and Atmospheric Administration’s (NOAA Surface Radiation (SURFRAD stations yields very good agreement with average bias lower than 5 W·m−2 and root mean square difference around 70 W·m−2. The algorithm performance is usually higher over areas characterized by low spatial variability in term of land cover type and surface biophysical properties. The technique does not involve retrieval and assessment of cloud properties and can be easily adapted to other meteorological satellites around the globe.

  3. Energy and environmental implications of copper production

    Energy Technology Data Exchange (ETDEWEB)

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

    1999-04-01

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

  4. Environmental considerations in energy crop production

    International Nuclear Information System (INIS)

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

    1994-01-01

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

  5. Net primary productivity (NPP) and associated parameters for the U.S. outer continental shelf waters, 1998-2009 (NODC Accession 0071184)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This accession consists of monthly net primary productivity (NPP) estimates for 1998-2009 derived from the Vertically Generalized Production Model (VGPM) for the 26...

  6. Between research and energy production

    International Nuclear Information System (INIS)

    Kirbus, F.B.

    1977-01-01

    When on March 20th, 1974, the nuclear power plant in Atucha, 100 km to the north-west of Argentine's capital Buenos Aires, built by Siemens, was taken into operation, it seemed as if South America had resolutely stepped into the atomic age. In the meantime, Brazil makes preparations for fortified construction of nuclear power plants and its own nuclear industry, and Mexico is accelerating its investigations in order to replace its dwindlung hydroelectric reserves as soon as possible with nuclear energy. The effect of the oil crisis was that Latin American countries, too, take a different look at the peaceful uses of atomic energy. (orig.) [de

  7. Energy production and human health

    International Nuclear Information System (INIS)

    Benson, J.R.; Brown, C.D.; Dixon-Davis, D.K.; Grahn, D.; Ludy, R.T.

    1977-01-01

    Progress is reported on the following research projects: development and evaluation of socioeconomic and demographic factors; and quantitative aspects of the impacts of energy-related effluents on human health. Environmental effects of electric power generation by gas, oil, coal, nuclear energy, and water were studied at 15 sites. A system of general demographic models was developed for projecting number of deaths and population size by sex, age, and cause of death through time for any defined initial population and set of vital rates

  8. Energy efficiency and cleaner production

    International Nuclear Information System (INIS)

    Konstantinoff, M.; Grozeva, Iv.

    1999-01-01

    Energy is the fundamental driver of the economic growth in the todays society. It is an absolute prerequisite for the industrial development in the developed countries as well as for improving the quality of life and reducing the poverty in the developing world. It is expected that the energy demand in the developing countries will increase rapidly in the next decades, and will even exceed the level of consumption in the rich countries due to rising population and incomes. The burning of fossil fuel, however, inevitably leads to negative environmental impact, which no longer can be neglected

  9. Energy production, conversion, storage, conservation, and coupling

    CERN Document Server

    Demirel, Yaşar

    2012-01-01

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

  10. Variations of net ecosystem production due to seasonal precipitation differences in a tropical dry forest of northwest Mexico

    Science.gov (United States)

    Verduzco, Vivian S.; Garatuza-Payán, Jaime; Yépez, Enrico A.; Watts, Christopher J.; Rodríguez, Julio C.; Robles-Morua, Agustin; Vivoni, Enrique R.

    2015-10-01

    Due to their large extent and high primary productivity, tropical dry forests (TDF) are important contributors to atmospheric carbon exchanges in subtropical and tropical regions. In northwest Mexico, a bimodal precipitation regime that includes winter precipitation derived from Pacific storms and summer precipitation from the North American monsoon (NAM) couples water availability with ecosystem processes. We investigated the net ecosystem production of a TDF ecosystem using a 4.5 year record of water and carbon fluxes obtained from the eddy covariance method complemented with remotely sensed data. We identified a large CO2 efflux at the start of the summer season that is strongly related to the preceding winter precipitation and greenness. Since this CO2 efflux occurs prior to vegetation green-up, we infer that respiration is mainly due to decomposition of soil organic matter accumulated from the prior growing season. Overall, ecosystem respiration has an important effect on the net ecosystem production but can be overwhelmed by the strength of the primary productivity during the NAM. Precipitation characteristics during NAM have significant controls on sustaining carbon fixation in the TDF into the fall season. We identified that a threshold of ~350 to 400 mm of monsoon precipitation leads to a switch in the annual carbon balance in the TDF ecosystem from a net source (+102 g C/m2/yr) to a net sink (-249 g C/m2/yr). This monsoonal precipitation threshold is typically exceeded one out of every 2 years. The close coupling of winter and summer periods with respect to carbon fluxes suggests that the annual carbon balance is dependent on precipitation amounts in both seasons in TDF ecosystems.

  11. Quantifying Human Appropriated Net Primary Productivity (HANPP) in a Ghanaian Cocoa System

    Science.gov (United States)

    Morel, A.; Adu-Bredu, S.; Adu Sasu, M.; Ashley Asare, R.; Boyd, E.; Hirons, M. A.; Malhi, Y.; Mason, J.; Norris, K.; Robinson, E. J. Z.; McDermott, C. L.

    2015-12-01

    Ghana is the second largest producer of cocoa (Theobroma cacoa), exporting approximately 18 percent of global volumes. These cocoa farms are predominantly small-scale, ranging in size from 2-4 hectares (ha). Traditionally, the model of cocoa expansion in Ghana relied on clearing new areas of forest and establishing a farm under remnant forest trees. This is increasingly less practical due to few unprotected forest areas remaining and management practices favoring close to full sun cocoa to maximize short-term yields. This study is part of a larger project, ECOLMITS, which is an interdisciplinary, ESPA-funded[1] initiative exploring the ecological limits of ecosystem system services (ESS) for alleviating poverty in small-scale agroforestry systems. The ecological study plots are situated within and around the Kakum National Forest, a well-protected, moist-evergreen forest of the Lower Guinea Forest region. Net primary productivity (NPP) is a measure of the rate at which carbon dioxide (CO2) is incorporated into plant tissues (e.g. canopy, stem and root). For this study, NPP was monitored in situ using methods developed by the Global Environmental Monitoring Network (GEM, http://gem.tropicalforests.ox.ac.uk/). By comparing NPP measured in intact forest and farms, the human appropriated NPP (HANPP) of this system can be estimated. The forest measures provide the "potential" NPP of the region, and then the reduction in NPP for farm plots is calculated for both land-cover change (HANPPLUC) and cocoa harvesting (HANPPHARV). The results presented are of the first year of NPP measurements across the cocoa landscape, including measurements from intact forest, logged forest and cocoa farms across a shade gradient and located at varying distances from the forest edge (e.g. 100 m, 500 m, 1 km and 5 km). These measures will have implications for carbon sequestration potential over the region and long-term sustainability of the Ghanaian cocoa sector. [1] Ecosystem Services for

  12. Quantitative assessment of human-induced impacts based on net primary productivity in Guangzhou, China.

    Science.gov (United States)

    Wu, Yanyan; Wu, Zhifeng

    2018-02-08

    Urban expansion and land cover change driven primarily by human activities have significant influences on the urban eco-environment, and together with climate change jointly alter net primary productivity (NPP). However, at the spatiotemporal scale, there has been limited quantitative analysis of the impacts of human activities independent of climate change on NPP. We chose Guangzhou city as a study area to analyze the impacts of human activities on NPP, as well as the spatiotemporal variations of those impacts within three segments, using a relative impact index (RII) based on potential NPP (NPP p ), actual NPP (NPP act ), and NPP appropriation due to land use/land cover change (NPP lulc ). The spatial patterns and dynamics of NPP act and NPP lulc were evaluated and the impacts of human activities on NPP during the process of urban sprawl were quantitatively analyzed and assessed using the RII. The results showed that NPP act and NPP lulc in the study area had clear spatial heterogeneity, between 2001 and 2013 there was a declining trend in NPP act while an increasing trend occurred in NPP lulc , and those trends were especially significant in the 10-40-km segment. The results also revealed that more than 91.0% of pixels in whole study region had positive RII values, while the lowest average RII values were found in the > 40-km segment (39.03%), indicating that human activities were not the main cause for the change in NPP there; meanwhile, the average RII was greater than 65.0% in the other two, suggesting that they were subjected to severe anthropogenic disturbances. The RII values in all three segments of the study area increased, indicating an increasing human interference. The 10-40-km buffer zone had the largest slope value (0.5665), suggesting that this segment was closely associated with growing human disturbances. Particularly noteworthy is the fact that the > 40-km segment had a large slope value (0.3323) and required more conservation efforts. Based

  13. Effects of vegetation heterogeneity and surface topography on spatial scaling of net primary productivity

    Science.gov (United States)

    Chen, J. M.; Chen, X.; Ju, W.

    2013-07-01

    Due to the heterogeneous nature of the land surface, spatial scaling is an inevitable issue in the development of land models coupled with low-resolution Earth system models (ESMs) for predicting land-atmosphere interactions and carbon-climate feedbacks. In this study, a simple spatial scaling algorithm is developed to correct errors in net primary productivity (NPP) estimates made at a coarse spatial resolution based on sub-pixel information of vegetation heterogeneity and surface topography. An eco-hydrological model BEPS-TerrainLab, which considers both vegetation and topographical effects on the vertical and lateral water flows and the carbon cycle, is used to simulate NPP at 30 m and 1 km resolutions for a 5700 km2 watershed with an elevation range from 518 m to 3767 m in the Qinling Mountain, Shanxi Province, China. Assuming that the NPP simulated at 30 m resolution represents the reality and that at 1 km resolution is subject to errors due to sub-pixel heterogeneity, a spatial scaling index (SSI) is developed to correct the coarse resolution NPP values pixel by pixel. The agreement between the NPP values at these two resolutions is improved considerably from R2 = 0.782 to R2 = 0.884 after the correction. The mean bias error (MBE) in NPP modelled at the 1 km resolution is reduced from 14.8 g C m-2 yr-1 to 4.8 g C m-2 yr-1 in comparison with NPP modelled at 30 m resolution, where the mean NPP is 668 g C m-2 yr-1. The range of spatial variations of NPP at 30 m resolution is larger than that at 1 km resolution. Land cover fraction is the most important vegetation factor to be considered in NPP spatial scaling, and slope is the most important topographical factor for NPP spatial scaling especially in mountainous areas, because of its influence on the lateral water redistribution, affecting water table, soil moisture and plant growth. Other factors including leaf area index (LAI) and elevation have small and additive effects on improving the spatial scaling

  14. Effects of vegetation heterogeneity and surface topography on spatial scaling of net primary productivity

    Directory of Open Access Journals (Sweden)

    J. M. Chen

    2013-07-01

    Full Text Available Due to the heterogeneous nature of the land surface, spatial scaling is an inevitable issue in the development of land models coupled with low-resolution Earth system models (ESMs for predicting land-atmosphere interactions and carbon-climate feedbacks. In this study, a simple spatial scaling algorithm is developed to correct errors in net primary productivity (NPP estimates made at a coarse spatial resolution based on sub-pixel information of vegetation heterogeneity and surface topography. An eco-hydrological model BEPS-TerrainLab, which considers both vegetation and topographical effects on the vertical and lateral water flows and the carbon cycle, is used to simulate NPP at 30 m and 1 km resolutions for a 5700 km2 watershed with an elevation range from 518 m to 3767 m in the Qinling Mountain, Shanxi Province, China. Assuming that the NPP simulated at 30 m resolution represents the reality and that at 1 km resolution is subject to errors due to sub-pixel heterogeneity, a spatial scaling index (SSI is developed to correct the coarse resolution NPP values pixel by pixel. The agreement between the NPP values at these two resolutions is improved considerably from R2 = 0.782 to R2 = 0.884 after the correction. The mean bias error (MBE in NPP modelled at the 1 km resolution is reduced from 14.8 g C m−2 yr−1 to 4.8 g C m−2 yr−1 in comparison with NPP modelled at 30 m resolution, where the mean NPP is 668 g C m−2 yr−1. The range of spatial variations of NPP at 30 m resolution is larger than that at 1 km resolution. Land cover fraction is the most important vegetation factor to be considered in NPP spatial scaling, and slope is the most important topographical factor for NPP spatial scaling especially in mountainous areas, because of its influence on the lateral water redistribution, affecting water table, soil moisture and plant growth. Other factors including leaf area index (LAI and elevation have small and additive effects on improving

  15. Biochemical and photosynthetic aspects of energy production

    Energy Technology Data Exchange (ETDEWEB)

    San Pietro, A [ed.

    1980-01-01

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

  16. An Evaluation of the NetBeans Module System as a Product line Implementation Technology

    DEFF Research Database (Denmark)

    Mærsk-Møller, Hans Martin; Jørgensen, Bo Nørregaard

    2011-01-01

    to standalone applications, these platforms and their facilities have not been investigated scientifically from a SPLE perspective. This paper remedies the situation by providing an evaluation and a discussion of the module system provided by NetBeans Platform (a RCP). The paper contributes to the catalog...

  17. The impact of dry matter loss during herbaceous biomass storage on net greenhouse gas emissions from biofuels production

    International Nuclear Information System (INIS)

    Emery, Isaac R.; Mosier, Nathan S.

    2012-01-01

    Life cycle inventory models of greenhouse gas emissions from biofuel production have become tightly integrated into government mandates and other policies to encourage biofuel production. Current models do not include life cycle impacts of biomass storage or reflect current literature on emissions from soil and biomass decomposition. In this study, the GREET model framework was used to determine net greenhouse gas emissions during ethanol production from corn and switchgrass via three biomass storage systems: wet ensiling of whole corn, and indoor and outdoor dry bale storage of corn stover and switchgrass. Dry matter losses during storage were estimated from the literature and used to modify GREET inventory analysis. Results showed that biomass stability is a key parameter affecting fuel production per farmed hectare and life cycle greenhouse gas emissions. Corn silage may generate 5358 L/ha of ethanol at 26.5 g CO 2 eq/MJ, relative to 5654 L/ha at 52.3 g CO 2 eq/MJ from combined corn stover and conventional grain corn ethanol production, or 3919 L/ha at 21.3 g CO 2 eq/MJ from switchgrass. Dry matter losses can increase net emissions by 3–25% (ensiling), 5–53% (bales outdoors), or 1–12% (bales indoors), decreasing the net GHG reduction of ethanol over gasoline by up to 10.9%. Greater understanding of biomass storage losses and greenhouse gas fluxes during storage is necessary to accurately assess biomass storage options to ensure that the design of biomass supply logistics systems meet GHG reduction mandates for biofuel production. -- Highlights: ► Analyzed the impact of biomass loss during storage. ► Probable dry matter losses strongly depend on storage method and infrastructure. ► Assessed impact of storage losses on LCA for cellulosic ethanol production. ► Storage losses increase GHG emissions by 1–53% depending upon storage conditions.

  18. Beam-energy and system-size dependence of dynamical net charge fluctuations

    Czech Academy of Sciences Publication Activity Database

    Abelev, B. I.; Aggarwal, M. M.; Ahammed, Z.; Anderson, B. D.; Arkhipkin, D.; Averichev, G. S.; Balewski, J.; Barannikova, O.; Barnby, L. S.; Baudot, J.; Baumgart, S.; Beavis, D.R.; Bellwied, R.; Benedosso, F.; Betancourt, M.J.; Betts, R. R.; Bhasin, A.; Bhati, A.K.; Bichsel, H.; Bielčík, Jaroslav; Bielčíková, Jana; Biritz, B.; Bland, L.C.; Bombara, M.; Bonner, B. E.; Botje, M.; Bouchet, J.; Braidot, E.; Brandin, A. V.; Bruna, E.; Bueltmann, S.; Burton, T. P.; Bysterský, Michal; Cai, X.Z.; Caines, H.; Sanchez, M.C.D.; Catu, O.; Cebra, D.; Cendejas, R.; Cervantes, M.C.; Chajecki, Z.; Chaloupka, Petr; Chattopadhyay, S.; Chen, H.F.; Chen, J.H.; Cheng, J.; Cherney, M.; Chikanian, A.; Choi, K.E.; Christie, W.; Clarke, R.F.; Codrington, M.J.M.; Corliss, R.; Cormier, T.M.; Coserea, R. M.; Cramer, J. G.; Crawford, H. J.; Das, D.; Dash, S.; Daugherity, M.; De Silva, L.C.; Dedovich, T. G.; DePhillips, M.; Derevschikov, A.A.; de Souza, R.D.; Didenko, L.; Djawotho, P.; Dunlop, J.C.; Mazumdar, M.R.D.; Edwards, W.R.; Efimov, L.G.; Elhalhuli, E.; Elnimr, M.; Emelianov, V.; Engelage, J.; Eppley, G.; Erazmus, B.; Estienne, M.; Eun, L.; Fachini, P.; Fatemi, R.; Fedorisin, J.; Feng, A.; Filip, P.; Finch, E.; Fine, V.; Fisyak, Y.; Gagliardi, C. A.; Gaillard, L.; Ganti, M. S.; Gangaharan, D.R.; Garcia-Solis, E.J.; Geromitsos, A.; Geurts, F.; Ghazikhanian, V.; Ghosh, P.; Gorbunov, Y.N.; Gordon, A.; Grebenyuk, O.; Grosnick, D.; Grube, B.; Guertin, S.M.; Guimaraes, K.S.F.F.; Gupta, A.; Gupta, N.; Guryn, W.; Haag, B.; Hallman, T.J.; Hamed, A.; Harris, J.W.; He, W.; Heinz, M.; Heppelmann, S.; Hippolyte, B.; Hirsch, A.; Hjort, E.; Hoffman, A.M.; Hoffmann, G.W.; Hofman, D.J.; Hollis, R.S.; Huang, H.Z.; Humanic, T.J.; Igo, G.; Iordanova, A.; Jacobs, P.; Jacobs, W.W.; Jakl, Pavel; Jena, C.; Jin, F.; Jones, C.L.; Jones, P.G.; Joseph, J.; Judd, E.G.; Kabana, S.; Kajimoto, K.; Kang, K.; Kapitán, Jan; Keane, D.; Kechechyan, A.; Kettler, D.; Khodyrev, V.Yu.; Kikola, D.P.; Kiryluk, J.; Kisiel, A.; Klein, S.R.; Knospe, A.G.; Kocoloski, A.; Koetke, D.D.; Kopytine, M.; Korsch, W.; Kotchenda, L.; Kushpil, Vasilij; Kravtsov, P.; Kravtsov, V.I.; Krueger, K.; Krus, M.; Kuhn, C.; Kumar, L.; Kurnadi, P.; Lamont, M.A.C.; Landgraf, J.M.; LaPointe, S.; Lauret, J.; Lebedev, A.; Lednický, Richard; Lee, Ch.; Lee, J.H.; Leight, W.; LeVine, M.J.; Li, N.; Li, C.; Li, Y.; Lin, G.; Lindenbaum, S.J.; Lisa, M.A.; Liu, F.; Liu, J.; Liu, L.; Ljubicic, T.; Llope, W.J.; Longacre, R.S.; Love, W.A.; Lu, Y.; Ludlam, T.; Ma, G.L.; Ma, Y.G.; Mahapatra, D.P.; Majka, R.; Mall, O.I.; Mangotra, L.K.; Manweiler, R.; Margetis, S.; Markert, C.; Matis, H.S.; Matulenko, Yu.A.; McShane, T.S.; Meschanin, A.; Milner, R.; Minaev, N.G.; Mioduszewski, S.; Mischke, A.; Mitchell, J.; Mohanty, B.; Morozov, D.A.; Munhoz, M. G.; Nandi, B.K.; Nattrass, C.; Nayak, T. K.; Nelson, J.M.; Netrakanti, P.K.; Ng, M.J.; Nogach, L.V.; Nurushev, S.B.; Odyniec, G.; Ogawa, A.; Okada, H.; Okorokov, V.; Olson, D.; Pachr, M.; Page, B.S.; Pal, S.K.; Pandit, Y.; Panebratsev, Y.; Panitkin, S.Y.; Pawlak, T.; Peitzmann, T.; Perevoztchikov, V.; Perkins, C.; Peryt, W.; Phatak, S.C.; Poljak, N.; Poskanzer, A.M.; Potukuchi, B.V.K.S.; Prindle, D.; Pruneau, C.; Pruthi, N.K.; Putschke, J.; Raniwala, R.; Raniwala, S.; Ray, R.L.; Redwine, R.; Reed, R.; Ridiger, A.; Ritter, H.G.; Roberts, J.B.; Rogachevskiy, O.V.; Romero, J.L.; Rose, A.; Roy, C.; Ruan, L.; Russcher, M.J.; Sahoo, R.; Sakrejda, I.; Sakuma, T.; Salur, S.; Sandweiss, J.; Sarsour, M.; Schambach, J.; Scharenberg, R.P.; Schmitz, N.; Seger, J.; Selyuzhenkov, I.; Seyboth, P.; Shabetai, A.; Shahaliev, E.; Shao, M.; Sharma, M.; Shi, S.S.; Shi, X.H.; Sichtermann, E.P.; Simon, F.; Singaraju, R.N.; Skoby, M.J.; Smirnov, N.; Snellings, R.; Sorensen, P.; Sowinski, J.; Spinka, H.M.; Srivastava, B.; Stadnik, A.; Stanislaus, T.D.S.; Staszak, D.; Strikhanov, M.; Stringfellow, B.; Suaide, A.A.P.; Suarez, M.C.; Subba, N.L.; Šumbera, Michal; Sun, X.M.; Sun, Y.; Sun, Z.; Surrow, B.; Symons, T.J.M.; de Toledo, A. S.; Takahashi, J.; Tang, A.H.; Tang, Z.; Tarnowsky, T.; Thein, D.; Thomas, J.H.; Tian, J.; Timmins, A.R.; Timoshenko, S.; Tokarev, M. V.; Trainor, T.A.; Tram, V.N.; Trattner, A.L.; Trentalange, S.; Tribble, R. E.; Tsai, O.D.; Ulery, J.; Ullrich, T.; Underwood, D.G.; Van Buren, G.; van Leeuwen, M.; Vander Molen, A.M.; Vanfossen, J.A.; Varma, R.; Vasconcelos, G.S.M.; Vasilevski, I.M.; Vasiliev, A. N.; Videbaek, F.; Vigdor, S.E.; Viyogi, Y. P.; Vokal, S.; Voloshin, S.A.; Wada, M.; Walker, M.; Wang, F.; Wang, G.; Wang, J.S.; Wang, Q.; Wang, X.; Wang, X.L.; Wang, Y.; Webb, G.; Webb, J.C.; Westfall, G.D.; Whitten, C.; Wieman, H.; Wissink, S.W.; Witt, R.; Wu, Y.; Tlustý, David; Xie, W.; Xu, N.; Xu, Q.H.; Xu, Y.; Xu, Z.; Yang, P.; Yepes, P.; Yip, K.; Yoo, I.K.; Yue, Q.; Zawisza, M.; Zbroszczyk, H.; Zhan, W.; Zhang, S.; Zhang, W.M.; Zhang, X.P.; Zhang, Y.; Zhang, Z.; Zhao, Y.; Zhong, C.; Zhou, J.; Zoulkarneev, R.; Zoulkarneeva, Y.; Zuo, J.X.

    2009-01-01

    Roč. 79, č. 2 (2009), 024906/1-024906/14 ISSN 0556-2813 R&D Projects: GA ČR GA202/07/0079; GA MŠk LC07048 Institutional research plan: CEZ:AV0Z10480505; CEZ:AV0Z10100502 Keywords : NET CHARGE * DYNAMICAL FLUCTUATIONS * HEAVY-ION COLLISIONS Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 3.477, year: 2009

  19. Toxicological aspects of energy production

    International Nuclear Information System (INIS)

    Sanders, C.L.

    1986-01-01

    Part I reviews the principles of toxicology, describes the biological fate of chemicals in the body, discusses basic pathobiology, and reviews short-term toxicity tests. Part II describes the toxicology and pathology of pollutants in several important organ systems. The greatest emphasis is placed on the respiratory tract because of its high probability as a route of exposure to pollutants from energy technologies and its high sensitivity to pollutant related tissue damage. Part III describes the toxicological aspects of specific chemical classes associated with fossil fuels; these include polycyclic hydrocarbons, gases and metals. Part IV describes the biomedical effects associated with each energy technology, including coal and oil, fossil fuel and biomass conversions, solar and geothermal and radiological health aspects associated with uranium mining, nuclear fission and fusion, and with nonionising radiations and electromagnetic fields

  20. Established dietary estimates of net acid production do not predict measured net acid excretion in patients with Type 2 diabetes on Paleolithic-Hunter-Gatherer-type diets.

    Science.gov (United States)

    Frassetto, L A; Shi, L; Schloetter, M; Sebastian, A; Remer, T

    2013-09-01

    Formulas developed to estimate diet-dependent net acid excretion (NAE) generally agree with measured values for typical Western diets. Whether they can also appropriately predict NAE for 'Paleolithic-type' (Paleo) diets-which contain very high amounts of fruits and vegetables (F&V) and concurrent high amounts of protein is unknown. Here, we compare measured NAEs with established NAE estimates in subjects with Type 2 diabetes (T2D). Thirteen subjects with well-controlled T2D were randomized to either a Paleo or American Diabetes Association (ADA) diet for 14 days. Twenty-four hour urine collections were performed at baseline and end of the diet period, and analyzed for titratable acid, bicarbonate and ammonium to calculate measured NAE. Three formulas for estimating NAE from dietary intake were used; two (NAE_diet R or L) that include dietary mineral intake and sulfate- and organic acid (OA) production, and one that is empirically derived (NAE_diet F) only considering potassium and protein intake. Measured NAE on the Paleo diet was significantly lower than on the ADA-diet (+31±22 vs 112±52 mEq/day, P=0.002). Although all formula estimates showed similar and reasonable correlations (r=0.52-0.76) with measured NAE, each one underestimated measured values. The formula with the best correlation did not contain an estimate of dietary OA production. Paleo-diets are lower in NAE than typical Western diets. However, commonly used formulas clearly underestimate NAE, especially for diets with very high F&V (as the Paleo diet), and in subjects with T2D. This may be due to an inappropriate estimation of proton loads stemming from OAs, underlining the necessity for improved measures of OA-related proton sources.

  1. Seasonal and Topographic Variation in Net Primary Productivity and Water Use Efficiency in a Southwest Sky Island Fores

    Science.gov (United States)

    Murphy, P.; Minor, R. L.; Sanchez-Canete, E. P.; Potts, D. L.; Barron-Gafford, G.

    2016-12-01

    Western North American Forests represent an uncertain sink for atmospheric carbon. While understanding of the physical drivers of productivity in these forests has grown in the last decade, the relative influence of topographic position in the complex terrain of montane systems remains understudied. The high-latitude mixed conifer forest ecosystems of the southern Arizona Madrean Sky Islands are characterized by low precipitation, high annual variation in temperature, and heterogeneous topography. Eddy covariance measurements these forests show distinct seasonal trends due to temperature and bi-modal precipitation patterns, but these measurements are unable to resolve potential differences in physiological function on opposing north and south aspects within the footprint of the tower. Most of the year, north aspects receive less energy input due to the oblique angle of incoming solar radiation, leading to a divergence in soil moistures and temperatures. However, overall movement of energy and material is much higher on these north aspects on an annual basis. The implications of these differences for net primary productivity (NPP) and water use efficiency (WUE) are poorly addressed in the literature. We evaluated the relative control that topography has on the physical environment (soil moisture and temperature) and how these factors affect water stress, NPP, and WUE. We combined leaf-level measurements of photosynthesis and transpiration with other physiological and meteorological measurements to determine how the dominant vegetation functions as a result of microclimatic conditions. Initial results from the spring and summer measurement periods suggest topographical differences in microclimate, resulting in differences in NPP in the spring, but not the summer. Also, each of the three species on the same aspect responded differently to the same microclimatic conditions, underscoring interspecific variation at the site. How might these patterns change throughout an

  2. Primary energy and greenhouse gas implications of increasing biomass production through forest fertilization

    Energy Technology Data Exchange (ETDEWEB)

    Sathre, Roger [Ecotechnology, Mid Sweden University, Ostersund (Sweden); Gustavsson, Leif [Ecotechnology, Mid Sweden University, Ostersund (Sweden); Bergh, Johan [Ecotechnology, Mid Sweden University, Ostersund (Sweden); Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences, Alnarp (Sweden)

    2010-04-15

    In this study we analyze the primary energy and greenhouse gas (GHG) implications of increasing biomass production by fertilizing 10% of Swedish forest land. We estimate the primary energy use and GHG emissions from forest management including production and application of N and NPK fertilizers. Based on modelled growth response, we then estimate the net primary energy and GHG benefits of using biomaterials and biofuels obtained from the increased forest biomass production. The results show an increased annual biomass harvest of 7.4 million t dry matter, of which 41% is large-diameter stemwood. About 6.9 PJ/year of additional primary energy input is needed for fertilizer production and forest management. Using the additional biomass for fuel and material substitution can reduce fossil primary energy use by 150 or 164 PJ/year if the reference fossil fuel is fossil gas or coal, respectively. About 22% of the reduced fossil energy use is due to material substitution and the remainder is due to fuel substitution. The net annual primary energy benefit corresponds to about 7% of Sweden's total primary energy use. The resulting annual net GHG emission reduction is 11.9 million or 18.1 million tCO{sub 2equiv} if the reference fossil fuel is fossil gas or coal, respectively, corresponding to 18% or 28% of the total Swedish GHG emissions in 2007. A significant one-time carbon stock increase also occurs in wood products and forest tree biomass. These results suggest that forest fertilization is an attractive option for increasing energy security and reducing net GHG emission.

  3. Primary energy and greenhouse gas implications of increasing biomass production through forest fertilization

    International Nuclear Information System (INIS)

    Sathre, Roger; Gustavsson, Leif; Bergh, Johan

    2010-01-01

    In this study we analyze the primary energy and greenhouse gas (GHG) implications of increasing biomass production by fertilizing 10% of Swedish forest land. We estimate the primary energy use and GHG emissions from forest management including production and application of N and NPK fertilizers. Based on modelled growth response, we then estimate the net primary energy and GHG benefits of using biomaterials and biofuels obtained from the increased forest biomass production. The results show an increased annual biomass harvest of 7.4 million t dry matter, of which 41% is large-diameter stemwood. About 6.9 PJ/year of additional primary energy input is needed for fertilizer production and forest management. Using the additional biomass for fuel and material substitution can reduce fossil primary energy use by 150 or 164 PJ/year if the reference fossil fuel is fossil gas or coal, respectively. About 22% of the reduced fossil energy use is due to material substitution and the remainder is due to fuel substitution. The net annual primary energy benefit corresponds to about 7% of Sweden's total primary energy use. The resulting annual net GHG emission reduction is 11.9 million or 18.1 million tCO 2equiv if the reference fossil fuel is fossil gas or coal, respectively, corresponding to 18% or 28% of the total Swedish GHG emissions in 2007. A significant one-time carbon stock increase also occurs in wood products and forest tree biomass. These results suggest that forest fertilization is an attractive option for increasing energy security and reducing net GHG emission.

  4. Primary energy and greenhouse gas implications of increasing biomass production through forest fertilization

    Energy Technology Data Exchange (ETDEWEB)

    Sathre, Roger; Gustavsson, Leif [Ecotechnology, Mid Sweden University, Oestersund (Sweden); Bergh, Johan [Ecotechnology, Mid Sweden University, Oestersund (Sweden); Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences, Alnarp (Sweden)

    2010-04-15

    In this study we analyze the primary energy and greenhouse gas (GHG) implications of increasing biomass production by fertilizing 10% of Swedish forest land. We estimate the primary energy use and GHG emissions from forest management including production and application of N and NPK fertilizers. Based on modelled growth response, we then estimate the net primary energy and GHG benefits of using biomaterials and biofuels obtained from the increased forest biomass production. The results show an increased annual biomass harvest of 7.4 million t dry matter, of which 41% is large-diameter stemwood. About 6.9 PJ/year of additional primary energy input is needed for fertilizer production and forest management. Using the additional biomass for fuel and material substitution can reduce fossil primary energy use by 150 or 164 PJ/year if the reference fossil fuel is fossil gas or coal, respectively. About 22% of the reduced fossil energy use is due to material substitution and the remainder is due to fuel substitution. The net annual primary energy benefit corresponds to about 7% of Sweden's total primary energy use. The resulting annual net GHG emission reduction is 11.9 million or 18.1 million tCO{sub 2equiv} if the reference fossil fuel is fossil gas or coal, respectively, corresponding to 18% or 28% of the total Swedish GHG emissions in 2007. A significant one-time carbon stock increase also occurs in wood products and forest tree biomass. These results suggest that forest fertilization is an attractive option for increasing energy security and reducing net GHG emission. (author)

  5. Federal Existing Buildings Handbook for Net Zero Energy, Water, and Waste

    Energy Technology Data Exchange (ETDEWEB)

    None

    2017-08-14

    In 2015, the U.S. Department of Energy’s Office of Energy Efficiency and Renewable Energy (EERE) defined zero energy buildings as "an energy-efficient building where, on a source energy basis, the actual annual delivered energy is less than or equal to the on-site renewable exported energy." This handbook is focused on applying the EERE definition of zero energy buildings to existing buildings in the federal sector. However, it is not intended to replace, substitute, or modify any statutory or regulatory requirements and mandates.

  6. Federal New Buildings Handbook for Net Zero Energy, Water, and Waste

    Energy Technology Data Exchange (ETDEWEB)

    None

    2017-08-14

    In 2015, the U.S. Department of Energy’s Office of Energy Efficiency and Renewable Energy (EERE) defined zero energy buildings as "an energy-efficient building where, on a source energy basis, the actual annual delivered energy is less than or equal to the on-site renewable exported energy." This document is focused on applying EERE’s definition of zero energy buildings to federal sector new buildings. However, it is not intended to replace, substitute, or modify any statutory or regulatory requirements and mandates.

  7. Chapter 7: Renewable Energy Options and Considerations for Net Zero Installations

    Energy Technology Data Exchange (ETDEWEB)

    Booth, Samuel

    2017-03-15

    This chapter focuses on renewable energy options for military installations. It discusses typical renewable technologies, project development, and gives examples. Renewable energy can be combined with conventional energy sources to provide part or all of the energy demand at an installation. The appropriate technology mix for an installation will depend on site-specific factors such as renewable resources, energy costs, local energy policies and incentives, available land, mission compatibility, and other factors. The objective of this chapter is to provide basic background information and resources on renewable energy options for NATO leaders and energy personnel.

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

    International Nuclear Information System (INIS)

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

    2014-01-01

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

  9. Automatic control algorithm effects on energy production

    Science.gov (United States)

    Mcnerney, G. M.

    1981-01-01

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

  10. Particle production at AGS energies

    International Nuclear Information System (INIS)

    Steadman, S.G.; Rothschild, P.J.; Sung, T.W.; Zachary, D.

    1995-01-01

    The authors discuss particle production from 14.6 A·GeV/c Si and 11.6 A·GeV/c Au projectiles on Al and Au targets. The second-level trigger utilized by E859 allows high precision measurements of K - , bar p, Λ and bar Λ. The bar Λ yield is larger than expected, and a surprisingly large fraction of the bar p's are observed to arise from the decay of bar Λ

  11. Redesign of a Rural Building in a Heritage Site in Italy: Towards the Net Zero Energy Target

    Directory of Open Access Journals (Sweden)

    Maurizio Cellura

    2017-07-01

    Full Text Available In order to achieve the ambitious objective of decarbonising the economy, it is mandatory, especially in Europe and in Italy, to include the retrofitting of existing buildings. In a country where a large share of existing buildings have heritage value, it is important to design effective retrofit solutions also in historical buildings. In this context, the paper describes the experience of re-design of an existing rural building located in Sicily, inside the ancient Greeks' “Valley of the Temples”. An energy audit was performed on the building, and its energy uses were thoroughly investigated. A building model was developed in the TRNSYS environment and its performances validated. The validated model was used for redesign studies aimed towards the achievement of the Net Zero Energy Building target. The best performing solutions to be applied to a case study like the Sanfilippo House were those regarding the management of the building, as in the case of the natural ventilation and the energy systems setpoints, that would allow a large impact (up to 10% reductions in energy uses on the energy performances of the building with no invasiveness, and those with very limited invasiveness and high impact on the energy efficiency of the building, as in the lighting scenario (up to 30% energy uses reduction. The most invasive actions can only be justified in the case of high energy savings, as in the case of the insulation of the roof, otherwise they should be disregarded.

  12. Productivity benefits of industrial energy efficiency measures

    Energy Technology Data Exchange (ETDEWEB)

    Worrell, Ernst; Laitner, John A.; Michael, Ruth; Finman, Hodayah

    2004-08-30

    We review the relationship between energy efficiency improvement measures and productivity in industry. We review over 70 industrial case studies from widely available published databases, followed by an analysis of the representation of productivity benefits in energy modeling. We propose a method to include productivity benefits in the economic assessment of the potential for energy efficiency improvement. The case-study review suggests that energy efficiency investments can provide a significant boost to overall productivity within industry. If this relationship holds, the description of energy-efficient technologies as opportunities for larger productivity improvements has significant implications for conventional economic assessments. The paper explores the implications this change in perspective on the evaluation of energy-efficient technologies for a study of the iron and steel industry in the US. This examination shows that including productivity benefits explicitly in the modeling parameters would double the cost-effective potential for energy efficiency improvement, compared to an analysis excluding those benefits. We provide suggestions for future research in this important area.

  13. Sectoral Energy, and Labour, Productivity Convergence

    International Nuclear Information System (INIS)

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

    2007-01-01

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

  14. Conjugated Polymers for Energy Production

    DEFF Research Database (Denmark)

    Livi, Francesco

    This dissertation is aimed at developing materials for flexible, large area, ITO-free polymer solar cells (PSCs) fully printed under ambient conditions. A large screening of conjugated polymers, both novel and well-known materials, has been carried out in order to find suitable candidates...... polymerization method for industrial production of polymers. Several DArP protocols have been employed for the synthesis of PPDTBT leading to polymers with high structural regularity and photovoltaic performances comparable with the same materials synthesized via Stille cross-coupling polymerization...

  15. An integrated renewable energy park approach for algal biofuel production in United States

    Energy Technology Data Exchange (ETDEWEB)

    Subhadra, Bobban [Department of Internal Medicine, School of Medicine, University of New Mexico, Albuquerque, NM 87131 (United States); Edwards, Mark [Marketing and Sustainability, W.P. Carey School of Business, Arizona State University, Tempe, AZ 85282 (United States)

    2010-09-15

    Algal biomass provides viable third generation feedstock for liquid transportation fuel that does not compete with food crops for cropland. However, fossil energy inputs and intensive water usage diminishes the positive aspects of algal energy production. An integrated renewable energy park (IREP) approach is proposed for aligning renewable energy industries in resource-specific regions in United States for synergistic electricity and liquid biofuel production from algal biomass with net zero carbon emissions. The benefits, challenges and policy needs of this approach are discussed. (author)

  16. An integrated renewable energy park approach for algal biofuel production in United States

    International Nuclear Information System (INIS)

    Subhadra, Bobban; Edwards, Mark

    2010-01-01

    Algal biomass provides viable third generation feedstock for liquid transportation fuel that does not compete with food crops for cropland. However, fossil energy inputs and intensive water usage diminishes the positive aspects of algal energy production. An integrated renewable energy park (IREP) approach is proposed for aligning renewable energy industries in resource-specific regions in United States for synergistic electricity and liquid biofuel production from algal biomass with net zero carbon emissions. The benefits, challenges and policy needs of this approach are discussed.

  17. Assessment of the Technical Potential for Achieving Net Zero-Energy Buildings in the Commercial Sector

    Energy Technology Data Exchange (ETDEWEB)

    Griffith, B.; Long, N.; Torcellini, P.; Judkoff, R.; Crawley, D.; Ryan, J.

    2007-12-01

    This report summarizes the findings from research conducted at NREL to assess the technical potential for zero-energy building technologies and practices to reduce the impact of commercial buildings on the U.S. energy system. Commercial buildings currently account for 18% of annual U.S. energy consumption, and energy use is growing along with overall floor area. Reducing the energy use of this sector will require aggressive research goals and rapid implementation of the research results.

  18. UV sensitivity of planktonic net community production in ocean surface waters

    OpenAIRE

    Regaudie de Gioux, Aurore; Agustí, Susana; Duarte, Carlos M.

    2014-01-01

    The net plankton community metabolism of oceanic surface waters is particularly important as it more directly affects the partial pressure of CO2 in surface waters and thus the air-sea fluxes of CO2. Plankton communities in surface waters are exposed to high irradiance that includes significant ultraviolet blue (UVB, 280-315 nm) radiation. UVB radiation affects both photosynthetic and respiration rates, increase plankton mortality rates, and other metabolic and chemical processes. Here we tes...

  19. Wood for energy production. Technology - environment - economy

    International Nuclear Information System (INIS)

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

    1999-01-01

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

  20. Wood for energy production. Technology - environment - economy

    Energy Technology Data Exchange (ETDEWEB)

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

    1999-10-01

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

  1. Energy aspects of microalgal biodiesel production

    Directory of Open Access Journals (Sweden)

    Edith Martinez-Guerra

    2016-03-01

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

  2. Inclusive production at LHC energies

    International Nuclear Information System (INIS)

    Merino, C.; Pajares, C.; Shabelski, Yu.M.

    2011-01-01

    We consider the first LHC data for pp collisions in the framework of Regge theory. The integral cross sections and inclusive densities of secondaries are determined by the Pomeron exchange, and we present the corresponding predictions for them. The first measurements of inclusive densities in the midrapidity region are in agreement with these predictions. The contribution of the baryon-number transfer due to String Junction diffusion in the rapidity space is at the origin of the differences in the inclusive spectra of particle and antiparticle in the central region, and this effect could be significant at LHC energies. We discuss the first data of ALICE and LHCb collaborations on the baryon/antibaryon asymmetry at LHC. (orig.)

  3. An Environmentally-Friendly Tourist Village in Egypt Based on a Hybrid Renewable Energy System––Part Two: A Net Zero Energy Tourist Village

    Directory of Open Access Journals (Sweden)

    Fahd Diab

    2015-07-01

    Full Text Available The main objective of this study is to discuss the economical and the environmental analysis of a net zero energy (NZE tourist village in Alexandria, Egypt, by maximizing the renewable energy fraction and minimizing the greenhouse gases (GHG emissions. The hybrid photovoltaics (PV/wind/diesel/battery system is found to be the optimum hybrid renewable energy system (HRES for the proposed tourist village under the study. The optimum HRES consists of 1600 kW of PV panels (58.09% solar energy penetration, 1000 kW of wind turbines (41.34% wind energy penetration, 1000 kW of power converters, 200 kW diesel generator (only 0.57% diesel generator penetration in addition to 2000 batteries with the capacity of 589 Ah each. The levelized cost of energy (COE from the optimum HRES is $0.17/kWh and the total net present cost (NPC of this system is $15,383,360. Additionally, the maximum renewable energy fraction is 99.1% and the amount of GHG emitted from the optimum HRES is only 31,289 kg/year, which is negligible in comparison with the other system configurations, therefore the optimum HRES can be considered as a green system. In addition to this, the achieved percentage of the capacity shortage and the unmet load in the optimal HRES is only 0% for both.

  4. A hybrid Genetic Algorithm and Monte Carlo simulation approach to predict hourly energy consumption and generation by a cluster of Net Zero Energy Buildings

    International Nuclear Information System (INIS)

    Garshasbi, Samira; Kurnitski, Jarek; Mohammadi, Yousef

    2016-01-01

    Graphical abstract: The energy consumption and renewable generation in a cluster of NZEBs are modeled by a novel hybrid Genetic Algorithm and Monte Carlo simulation approach and used for the prediction of instantaneous and cumulative net energy balances and hourly amount of energy taken from and supplied to the central energy grid. - Highlights: • Hourly energy consumption and generation by a cluster of NZEBs was simulated. • Genetic Algorithm and Monte Carlo simulation approach were employed. • Dampening effect of energy used by a cluster of buildings was demonstrated. • Hourly amount of energy taken from and supplied to the grid was simulated. • Results showed that NZEB cluster was 63.5% grid dependant on annual bases. - Abstract: Employing a hybrid Genetic Algorithm (GA) and Monte Carlo (MC) simulation approach, energy consumption and renewable energy generation in a cluster of Net Zero Energy Buildings (NZEBs) was thoroughly investigated with hourly simulation. Moreover, the cumulative energy consumption and generation of the whole cluster and each individual building within the simulation space were accurately monitored and reported. The results indicate that the developed simulation algorithm is able to predict the total instantaneous and cumulative amount of energy taken from and supplied to the central energy grid over any time period. During the course of simulation, about 60–100% of total daily generated renewable energy was consumed by NZEBs and up to 40% of that was fed back into the central energy grid as surplus energy. The minimum grid dependency of the cluster was observed in June and July where 11.2% and 9.9% of the required electricity was supplied from the central energy grid, respectively. On the other hand, the NZEB cluster was strongly grid dependant in January and December by importing 70.7% and 76.1% of its required energy demand via the central energy grid, in the order given. Simulation results revealed that the cluster was 63

  5. 'PSA-SPN' - A Parameter Sensitivity Analysis Method Using Stochastic Petri Nets: Application to a Production Line System

    International Nuclear Information System (INIS)

    Labadi, Karim; Saggadi, Samira; Amodeo, Lionel

    2009-01-01

    The dynamic behavior of a discrete event dynamic system can be significantly affected for some uncertain changes in its decision parameters. So, parameter sensitivity analysis would be a useful way in studying the effects of these changes on the system performance. In the past, the sensitivity analysis approaches are frequently based on simulation models. In recent years, formal methods based on stochastic process including Markov process are proposed in the literature. In this paper, we are interested in the parameter sensitivity analysis of discrete event dynamic systems by using stochastic Petri nets models as a tool for modelling and performance evaluation. A sensitivity analysis approach based on stochastic Petri nets, called PSA-SPN method, will be proposed with an application to a production line system.

  6. Optimizing Photosynthetic and Respiratory Parameters Based on the Seasonal Variation Pattern in Regional Net Ecosystem Productivity Obtained from Atmospheric Inversion

    Science.gov (United States)

    Chen, Z.; Chen, J.; Zheng, X.; Jiang, F.; Zhang, S.; Ju, W.; Yuan, W.; Mo, G.

    2014-12-01

    In this study, we explore the feasibility of optimizing ecosystem photosynthetic and respiratory parameters from the seasonal variation pattern of the net carbon flux. An optimization scheme is proposed to estimate two key parameters (Vcmax and Q10) by exploiting the seasonal variation in the net ecosystem carbon flux retrieved by an atmospheric inversion system. This scheme is implemented to estimate Vcmax and Q10 of the Boreal Ecosystem Productivity Simulator (BEPS) to improve its NEP simulation in the Boreal North America (BNA) region. Simultaneously, in-situ NEE observations at six eddy covariance sites are used to evaluate the NEE simulations. The results show that the performance of the optimized BEPS is superior to that of the BEPS with the default parameter values. These results have the implication on using atmospheric CO2 data for optimizing ecosystem parameters through atmospheric inversion or data assimilation techniques.

  7. Environmental costs of fossil fuel energy production

    International Nuclear Information System (INIS)

    Riva, A.; Trebeschi, C.

    1997-01-01

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

  8. Wind energy status in renewable electrical energy production in Turkey

    International Nuclear Information System (INIS)

    Kaygusuz, Kamil

    2010-01-01

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

  9. Demonstration of the Energy Component of the Installation Master Plan Using the Net Zero Energy Planner Tool

    Science.gov (United States)

    2015-09-01

    electricity , natural gas, propane, and energy generated 12 from renewable sources (e.g., solar, wind, hydro , etc.). It is also important to...for energy intensity, that meets energy security requirements at a lower cost, and that controls electrical capacity growth requirements. If the... energy intensity, meeting energy security requirements at a lower cost, and controlling electrical capacity growth requirements. Rapid deployment

  10. Energy and economic analysis of greenhouse strawberry production in Tehran province of Iran

    International Nuclear Information System (INIS)

    Banaeian, Narges; Omid, Mahmoud; Ahmadi, Hojat

    2011-01-01

    The aims of this study were to determine energy use pattern, to investigate the energy use efficiency, and to make an economical analysis in greenhouse strawberry production in Iran. Data used in this study were obtained from 25 greenhouse strawberry growers using a face to face questionnaire method. The results indicate that greenhouse strawberry production consumed a total energy of 121891.33 MJ ha -1 . About 78% of this was generated by diesel fuel, 10% from chemical fertilizers, and 4.5% from electricity. Energy ratio, specific energy, net energy and energy intensiveness of greenhouse strawberry production were 0.15, 12.55 MJ kg -1 , -683488.37 MJ ha -1 and 8.18 MJ $ -1 , respectively. Determination of the efficient allocation of energy resources were modeled by Cobb-Douglas production function. Econometric model evaluation showed the impact of human labor, fertilizers, installation of equipment and transportation costs for strawberry production were all significant at 1% level. The elasticity estimates indicated that among the cost inputs, transportation is the most important input (-0.75) that influences total cost of production, followed by labor (0.31), fertilizers (0.18) and installation of equipments (0.22). The benefit-cost ratio and net return were obtained as 1.74 and 151907.91 $ ha -1 , respectively.

  11. ENERGY USE IN CITRUS PRODUCTION OF MAZANDARAN ...

    African Journals Online (AJOL)

    Prof. Adipala Ekwamu

    The aim of this study was to evaluate energy use in citrus production in the Mazandaran Province in Iran. Data used in this study were obtained from 155 farmers using a face-to-face interview method. The total energy .... control mainly were mechanised and a few of them ... fertilisers was manual; while manure application.

  12. All energy production involves danger

    International Nuclear Information System (INIS)

    Pleym, H.

    1976-01-01

    s pointed out that while the protective ozone layer in the upper atmosphere is threatened by supersonic air traffic and releases of freon, there is an increase in the concentration of ozone in the biosphere. The biological effect of ozone in forming free radicals is similar to the biological effect of ionising rad radiation, and the normal atmospheric concentration of ozone produces 3600 times the number of free radicals per person per year as does a background radiation of 100 mrem per year. It is also pointed out that the limits for sulphur oxides and nitrogen oxides in the atmosphere are 100 and 5 times the background levels respectively, while the limit for radioactive release is 1/100 th of the background level. The transmission of solar energy from space stations by microwave is also thought to be dubious due to possible biological effects of such radiation. In conclusion a balanced view on the biological and environmental hazards of power generation from all sources, and not only nuclear, is called for. (JIW)

  13. How can we improve the energy balance of ethanol production from wheat?

    Energy Technology Data Exchange (ETDEWEB)

    Jerry D. Murphy; Niamh M. Power [University College Cork, Cork (Ireland). Department of Civil and Environmental Engineering

    2008-08-15

    The gross energy in ethanol using wheat as a feedstock in Ireland is 66 GJ/ha/a. The net energy production is 25 GJ/ha/a. A model is proposed, whereby the ethanol production process is combined with combustion of straw, and digestion of stillage, resulting in two transport fuels; ethanol and biomethane. In the proposed system stillage is not dried, reducing the thermal demand by 35%. A quarter of the straw associated with the wheat grain is sufficient, when combusted, to satisfy the reduced thermal demands. Stillage is digested wet; the biogas is scrubbed, compressed and utilised as a transport fuel. The net energy now is 72 GJ/ha/a. The production cost of biomethane is two thirds that of ethanol. 37 refs., 1 fig., 10 tabs.

  14. Emission of CO2 from energy crop production

    International Nuclear Information System (INIS)

    Turhollow, A.F.

    1991-01-01

    The production of cellulosic energy crops (e.g., short rotation woody crops and herbaceous crops) make a net contribution of CO 2 to the atmosphere to the extent that fossil-fuel based inputs are used in their production. The CO 2 released from the use of the biomass is merely CO 2 that has recently been removed from the atmosphere by the plant growth process. Fossil inputs used in the production of energy corps include energy invested in fertilizers and pesticides, and petroleum fuels used for machinery operation such as site preparation, weed control, harvesting, and hauling. Fossil inputs used come from petroleum, natural gas, and electricity derived from fossil sources. No fossil inputs for the capital used to produce fertilizers, pesticides, or machinery is calculated in this analysis. In this paper calculations are made for the short rotation woody crop hybrid poplar (Populus spp.), the annual herbaceous crop sorghum (Sorghum biocolor [L.] Moench), and the perennial herbaceous crop switchgrass (Panicum virgatum L.). For comparison purposes, emissions of CO 2 from corn (Zea mays L.) are calculated

  15. Full chain energy analysis of biodiesel production from palm oil in Thailand

    Energy Technology Data Exchange (ETDEWEB)

    Pleanjai, Somporn; Gheewala, Shabbir H. [The Joint Graduate School of Energy and Environment, King Mongkut' s University of Technology Thonburi, 126 Pracha-Uthit Road, Bangmod, Tungkru, Bangkok 10140 (Thailand)

    2009-11-15

    Biodiesel from palm oil has been considered for partial substitution of diesel fuel for transportation in Thailand. The Thai government recently has set up a production target of 8.5 million liters per day of palm oil-based biodiesel by 2011. The aim of this study is to investigate the energy consumption of palm methyl ester (PME) production in Thailand using a life cycle approach compared to other possible oil crops for biodiesel production including jatropha and coconut. The main contributors to the energy use are cultivation, oil production, transesterification and transportation. Taking into account only fossil fuel or petroleum inputs in the production cycle, the energy analysis provides results in favour of PME in Thailand. The net energy balance (NEB) and net energy ratio (NER) of PME and co-products are 100.84 GJ/ha and 3.58, respectively. The NER of PME without co-products is 2.42, which is still higher than one indicating a favourable result. The results are important in selecting an appropriate feedstock for biodiesel production and this study will support policy makers in the energy sector to make informed decisions vis-a-vis promotion of oil palm plantation for biodiesel. This will also support the Thai government in its policy to promote the use of indigenous and renewable sources for transportation fuels. (author)

  16. Federal R&D Agenda for Net Zero Energy, High-Performance Green Buildings

    National Research Council Canada - National Science Library

    2008-01-01

    .... greenhouse gas emissions (GHGs). If current trends continue, buildings worldwide will become the top energy consumers by 2025, and are likely to use as much energy as industry and transportation combined by 2050...

  17. Federal Research and Development Agenda for Net-Zero Energy, High-Performance Green Buildings

    National Research Council Canada - National Science Library

    2008-01-01

    .... greenhouse gas emissions (GHGs). If current trends continue, buildings worldwide will become the top energy consumers by 2025, and are likely to use as much energy as industry and transportation combined by 2050...

  18. How to Define Nearly Net Zero Energy Buildings nZEB

    DEFF Research Database (Denmark)

    Kurnitski, Jarek; Allard, Francis; Braham, Derrick

    2011-01-01

    or maximum harmonized requirements as well as details of energy performance calculation framework, it will be up to the Member State to define what these for them exactly constitute. In the definition, local conditions are to be obviously taken into account, but the uniform methodology can be used in all......This REHVA Task Force proposes a technical definition for nearly zero energy buildings required in the implementation of the Energy performance of buildings directive recast. Energy calculation framework and system boundaries associated with the definition are provided to specify which energy flows...... in which way are taken into account in the energy performance assessment. The intention of the Task Force is to help the experts in the Member States in defining the nearly zero energy buildings in a uniform way. The directive requires nearly zero energy buildings, but since it does not give minimum...

  19. Federal Research and Development Agenda for Net-Zero Energy, High-Performance Green Buildings

    Science.gov (United States)

    2008-10-21

    transportation combined by 2050 (DOE 2007a). Figure 1. Energy Consumption in the United States Source: 2007 DOE Buildings Energy Data Book , Tables...poor indoor air quality (IAQ) include Legionnaires’ disease, heart disease and lung cancer from secondhand smoke, and carbon monoxide poisoning. More...www.eere.energy.gov/buildings/publications/pdfs/highperformance/commercialbuildin gsroadmap.pdf DOE. 2007a. Buildings energy data book . http

  20. Net Primary Production and Carbon Stocks for Subarctic Mesic-Dry Tundras with Contrasting Microtopography, Altitude, and Dominant Species

    DEFF Research Database (Denmark)

    Campioli, Matteo; Michelsen, Anders; Demey, A

    2009-01-01

    Mesic-dry tundras are widespread in the Arctic but detailed assessments of net primary production (NPP) and ecosystem carbon (C) stocks are lacking. We addressed this lack of knowledge by determining the seasonal dynamics of aboveground vascular NPP, annual NPP, and whole-ecosystem C stocks in five...... mesic-dry tundras in Northern Sweden with contrasting microtopography, altitude, and dominant species. Those measurements were paralleled by the stock assessments of nitrogen (N), the limiting nutrient. The vascular production was determined by harvest or in situ growing units, whereas the nonvascular...... hermaphroditum is more productive than Cassiope tetragona vegetation. Although the large majority of the apical NPP occurred in early-mid season (85%), production of stems and evergreen leaves proceeded until about 2 weeks before senescence. Most of the vascular vegetation was belowground (80%), whereas most...

  1. Energy and GHG balances of ethanol production from cane molasses in Indonesia

    International Nuclear Information System (INIS)

    Khatiwada, Dilip; Venkata, Bharadwaj K.; Silveira, Semida; Johnson, Francis X.

    2016-01-01

    Highlights: • This study performs LCA analysis of sugarcane-based bioethanol production. • Energy and GHG balances are evaluated in the entire production chain. • Sensitivity analysis is performed to identify key influencing parameters. • Efficient cogeneration and biogas recovery enhances energy and climate gains. • Results of LCA studies and issues related to land use change impact are discussed. - Abstract: This study analyses the sustainability of fuel ethanol production from cane molasses in Indonesia. Life cycle assessment (LCA) is performed to evaluate the net emissions (climate change impact) and energy inputs (resource consumption) in the production chain. The lifecycle greenhouse gas (GHG) emissions in the production and use of ethanol are estimated at 29 gCO 2eq per MJ of ethanol produced which is a 67% reduction in comparison to gasoline emissions. Net Energy Value (NEV) and Net Renewable Energy Value (NREV) are −7 MJ/l and 17.7 MJ/l, while the energy yield ratio (ER) is 6.1. Economic allocation is chosen for dividing environmental burdens and resource consumption between sugar (i.e. main product) and molasses (i.e. co-product used for fuel production). Sensitivity analysis of various parameters is performed. The emissions and energy values are highly sensitive to sugarcane yield, ethanol yield, and the price of molasses. The use of sugarcane biomass residues (bagasse/trash) for efficient cogeneration, and different waste management options for the treatment of spent wash (effluent of distilleries) are also explored. Surplus bioelectricity generation in the efficient cogeneration plant, biogas recovery from wastewater treatment plant, and their use for fossil fuel substitution can help improve energy and environmental gains. The study also compares important results with other relevant international studies and discusses issues related to land use change (LUC) impact.

  2. Exploring Global Patterns in Human Appropriation of Net Primary Production Using Earth Observation Satellites and Statistical Data

    Science.gov (United States)

    Imhoff, M.; Bounoua, L.

    2004-12-01

    A unique combination of satellite and socio-economic data were used to explore the relationship between human consumption and the carbon cycle. Biophysical models were applied to consumption data to estimate the annual amount of Earth's terrestrial net primary production humans require for food, fiber and fuel using the same modeling architecture as satellite-supported NPP measurements. The amount of Earth's NPP required to support human activities is a powerful measure of the aggregate human impacts on the biosphere and indicator of societal vulnerability to climate change. Equations were developed estimating the amount of landscape-level NPP required to generate all the products consumed by 230 countries including; vegetal foods, meat, milk, eggs, wood, fuel-wood, paper and fiber. The amount of NPP required was calculated on a per capita basis and projected onto a global map of population to create a spatially explicit map of NPP-carbon demand in units of elemental carbon. NPP demand was compared to a map of Earth's average annual net primary production or supply created using 17 years (1982-1998) of AVHRR vegetation index to produce a geographically accurate balance sheet of terrestrial NPP-carbon supply and demand. Globally, humans consume 20 percent of Earth's total net primary production on land. Regionally the NPP-carbon balance percentage varies from 6 to over 70 percent and locally from near 0 to over 30,000 percent in major urban areas. The uneven distribution of NPP-carbon supply and demand, indicate the degree to which various human populations rely on NPP imports, are vulnerable to climate change and suggest policy options for slowing future growth in NPP demand.

  3. Targeting Net Zero Energy at Marine Corps Air Station Miramar: Assessment and Recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Booth, S.; Barnett, J.; Burman, K.; Hambrick, J.; Helwig, M.; Westby, R.

    2010-12-01

    The U.S. Department of Defense (DoD) is the largest energy consumer in the U.S. government. Present energy use impacts DoD global operations by constraining freedom of action and self-sufficiency, demanding enormous economic resources, and putting many lives at risk in logistics support for deployed environments. There are many opportunities for DoD to more effectively meet energy requirements through a combination of human actions, energy efficiency technologies, and renewable energy resources. In 2008, a joint initiative was formed between DoD and the U.S. Department of Energy (DOE) to address military energy use. This initiative created a task force comprised of representatives from each branch of the military, the Office of the Secretary of Defense (OSD), the Federal Energy Management Program (FEMP), and the National Renewable Energy Laboratory (NREL) to examine the potential for ultra high efficiency military installations. This report presents an assessment of Marine Corps Air Station (MCAS) Miramar, selected by the task force as the initial prototype installation based on its strong history of energy advocacy and extensive track record of successful energy projects.

  4. Self-energy production applied to buildings

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-07-01

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

  5. Grasses for energy production: hydrological guidelines

    Energy Technology Data Exchange (ETDEWEB)

    Hall, R.L.

    2003-07-01

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

  6. Nuclear energy for sustainable Hydrogen production

    International Nuclear Information System (INIS)

    Gyoshev, G.

    2004-01-01

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

  7. The energy balance of utilising meadow grass in Danish biogas production

    DEFF Research Database (Denmark)

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

    2015-01-01

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

  8. Environmental consequences of energy production: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    none,

    1989-01-01

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

  9. Production and transfer of energy and information in Hamiltonian systems.

    Directory of Open Access Journals (Sweden)

    Chris G Antonopoulos

    Full Text Available We present novel results that relate energy and information transfer with sensitivity to initial conditions in chaotic multi-dimensional Hamiltonian systems. We show the relation among Kolmogorov-Sinai entropy, Lyapunov exponents, and upper bounds for the Mutual Information Rate calculated in the Hamiltonian phase space and on bi-dimensional subspaces. Our main result is that the net amount of transfer from kinetic to potential energy per unit of time is a power-law of the upper bound for the Mutual Information Rate between kinetic and potential energies, and also a power-law of the Kolmogorov-Sinai entropy. Therefore, transfer of energy is related with both transfer and production of information. However, the power-law nature of this relation means that a small increment of energy transferred leads to a relatively much larger increase of the information exchanged. Then, we propose an "experimental" implementation of a 1-dimensional communication channel based on a Hamiltonian system, and calculate the actual rate with which information is exchanged between the first and last particle of the channel. Finally, a relation between our results and important quantities of thermodynamics is presented.

  10. Net ecosystem exchange and energy fluxes measured with the eddy covariance technique in a western Siberian bog

    Directory of Open Access Journals (Sweden)

    P. Alekseychik

    2017-08-01

    Full Text Available Very few studies of ecosystem–atmosphere exchange involving eddy covariance data have been conducted in Siberia, with none in the western Siberian middle taiga. This work provides the first estimates of carbon dioxide (CO2 and energy budgets in a typical bog of the western Siberian middle taiga based on May–August measurements in 2015. The footprint of measured fluxes consisted of a homogeneous mixture of tree-covered ridges and hollows with the vegetation represented by typical sedges and shrubs. Generally, the surface exchange rates resembled those of pine-covered bogs elsewhere. The surface energy balance closure approached 100 %. Net CO2 uptake was comparatively high, summing up to 202 gC m−2 for the four measurement months, while the Bowen ratio was seasonally stable at 28 %. The ecosystem turned into a net CO2 source during several front passage events in June and July. The periods of heavy rain helped keep the water table at a sustainably high level, preventing a usual drawdown in summer. However, because of the cloudy and rainy weather, the observed fluxes might rather represent the special weather conditions of 2015 than their typical magnitudes.

  11. Oil sand synfuel production using nuclear energy

    International Nuclear Information System (INIS)

    Barnert, H.

    1984-10-01

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

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

    Science.gov (United States)

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

    2017-01-01

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

  13. Federal R&D Agenda for Net Zero Energy, High-Performance Green Buildings

    Science.gov (United States)

    2008-09-30

    Source: 2007 DOE Buildings Energy Data Book . Tables 1.1.3, 1.2.3, 1.3.3 Energy consumption associated with buildings has a substantial impact on...from poor indoor air quality (IAQ) include Legionnaire’s disease, heart disease and lung cancer from secondhand smoke, and carbon monoxide poisoning...publications/pdfs/highperformance/commercialbuildi ngsroadmap.pdf DOE. 2007a. Buildings energy data book . http://buildingsdatabook.eren.doe.gov/ DOE

  14. Towards a Net Zero Building Cluster Energy Systems Analysis for a Brigade Combat Team Complex

    Science.gov (United States)

    2010-05-01

    of technologies, like cogeneration or combined heat and power, waste heat recovery, biomass, geother- mal energy , solar heating (and cooling), and...financial evaluation of all projects. The costs of natural gas, alternative energy technology, alter- native fuels and the impact of greenhouse gas...distribution is unlimited. 1 Proceedings of ASME 2010 4th International Conference on Energy Sustainability ES2010 May 17-22, 2010 Phoenix

  15. Analysis to determine the maximum dimensions of flexible apertures in sensored security netting products.

    Energy Technology Data Exchange (ETDEWEB)

    Murton, Mark; Bouchier, Francis A.; vanDongen, Dale T.; Mack, Thomas Kimball; Cutler, Robert P; Ross, Michael P.

    2013-08-01

    Although technological advances provide new capabilities to increase the robustness of security systems, they also potentially introduce new vulnerabilities. New capability sometimes requires new performance requirements. This paper outlines an approach to establishing a key performance requirement for an emerging intrusion detection sensor: the sensored net. Throughout the security industry, the commonly adopted standard for maximum opening size through barriers is a requirement based on square inchestypically 96 square inches. Unlike standard rigid opening, the dimensions of a flexible aperture are not fixed, but variable and conformable. It is demonstrably simple for a human intruder to move through a 96-square-inch opening that is conformable to the human body. The longstanding 96-square-inch requirement itself, though firmly embedded in policy and best practice, lacks a documented empirical basis. This analysis concluded that the traditional 96-square-inch standard for openings is insufficient for flexible openings that are conformable to the human body. Instead, a circumference standard is recommended for these newer types of sensored barriers. The recommended maximum circumference for a flexible opening should be no more than 26 inches, as measured on the inside of the netting material.

  16. LTE UE Energy Saving by Applying Carrier Aggregation in a HetNet Scenario

    DEFF Research Database (Denmark)

    Lauridsen, Mads; Wang, Hua; Mogensen, Preben

    2013-01-01

    In this work it is examined if downlink Carrier Aggregation (CA) can be used to save UE energy. A dual-receiver LTE release 10 UE is compared with a single-receiver LTE release 8 UE. The models are based on scaling of an existing LTE release 8 UE power model. The energy consumption of the UEs...... is examined in a Heterogeneous Network scenario consisting of macro and small cells. The unexpected conclusion is that CA UEs can save energy, compared to LTE release 8 UEs, if they, depending on cell load, experience a throughput gain of 20%. However if the UE throughput is unaltered the energy consumption...

  17. Energy use and economic analysis of strawberry production in Sanandaj zone of Iran

    Directory of Open Access Journals (Sweden)

    Salami, P.

    2010-01-01

    Full Text Available The aim of this study was to determine the energy consumption and economic analysis for strawberry production. The data were collected from 60 farmers growing strawberry in the Sanandaj zone of Iran by using a face-to-face questionnaire in August-September 2009. The plowing operation at the study area was done by two methods; manually plow (P1 and machinery plow (P2. Also the irrigation operation was done by two methods; pumping irrigation (P and non pumping irrigation (NP. Univariate analysis of variance was used for finding the differences among the total energy used for production and profitability of this crop in the different methods at the 5% and 1% level. Total energy used in various farm operations during strawberry production was 53,605 MJ.ha-1. Total energy output was 17,338 MJ.ha-1, and the average annual yield of strawberry farms was 9,125 kg.ha-1. Energy efficiency was 0.32, and energy productivity calculated as 0.17 kg.MJ-1. This means a production of 0.17 kg per unit energy. The difference between total input energy in the different irrigation types (NP and P is significant at 1% level. There is not any significant difference between different plow types at the 5% level. The interaction of irrigation types and plow types is significant at 5% level. The profit-cost ratio, productivity, and net profit in the strawberry production are 1.2, 0.99, and 1,825 $.ha-1, respectively. The difference between net return in the different irrigation types (NP and P is significant at 5% level. The difference between net return in the different plow types (P1 and P2 is significant at 1% level.

  18. Algae production for energy and foddering

    Energy Technology Data Exchange (ETDEWEB)

    Bai, Attila; Jobbagy, Peter; Durko, Emilia [University of Debrecen, Faculty of Applied Economics and Rural Development (UD-FAERD), Centre for Agricultural and Applied Economic Sciences, Debrecen (Hungary)

    2011-09-15

    This study not only presents the results of our own experiments in alga production, but also shows the expected economic results of the various uses of algae (animal feed, direct burning, pelleting, bio-diesel production), the technical characteristics of a new pelleting method based on literature, and also our own recommended alga production technology. In our opinion, the most promising alternative could be the production of alga species with high levels of oil content, which are suitable for utilization as by-products for animal feed and in the production of bio-diesel, as well as for use in waste water management and as a flue gas additive. Based on the data from our laboratory experiments, of the four species we analyzed, Chlorella vulgaris should be considered the most promising species for use in large-scale experiments. Taking expenses into account, our results demonstrate that the use of algae for burning technology purposes results in a significant loss under the current economic conditions; however, the utilization of algae for feeding and bio-diesel purposes - in spite of their innovative nature - is nearing the level needed for competitiveness. By using the alga production technology recommended by us and described in the present study in detail, with an investment of 545 to 727 thousand EUR/ha, this technology should be able to achieve approximately 0-29 thousand EUR/ha net income, depending on size. More favorable values emerge in the case of the 1-ha (larger) size, thanks to the significant savings on fixed costs (depreciation and personnel costs). (orig.)

  19. VARIABILITY IN NET PRIMARY PRODUCTION AND CARBON STORAGE IN BIOMASS ACROSS OREGON FORESTS - AN ASSESSMENT INTEGRATING DATA FROM FOREST INVENTORIES, INTENSIVE SITES, AND REMOTE SENSING. (R828309)

    Science.gov (United States)

    We used a combination of data from USDA Forest Service inventories, intensivechronosequences, extensive sites, and satellite remote sensing, to estimate biomassand net primary production (NPP) for the forested region of western Oregon. Thestudy area was divided int...

  20. Seasonal Oxygen Dynamics in a Warm Temperate Estuary: Effects of Hydrologic Variability on Measurements of Primary Production, Respiration, and Net Metabolism

    Science.gov (United States)

    Seasonal responses in estuarine metabolism (primary production, respiration, and net metabolism) were examined using two complementary approaches. Total ecosystem metabolism rates were calculated from dissolved oxygen time series using Odum’s open water method. Water column rates...

  1. Net primary productivity collected from New Horizon in Gulf of California and North Pacific Ocean from 2004-07-14 to 2008-08-06 (NCEI Accession 0130076)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Net primary productivity determined from 13C-labeled in situ incubations. Water collected via Niskin bottle was incubated with labeled bicarbonate for 24 hours at...

  2. Biometric-based estimation of net ecosystem production in a mature Japanese cedar (Cryptomeria japonica) plantation beneath a flux tower.

    Science.gov (United States)

    Yashiro, Yuichiro; Lee, Na-Yeon M; Ohtsuka, Toshiyuki; Shizu, Yoko; Saitoh, Taku M; Koizumi, Hiroshi

    2010-07-01

    Quantification of carbon budgets and cycling in Japanese cedar (Cryptomeria japonica D. Don) plantations is essential for understanding forest functions in Japan because these plantations occupy about 20% of the total forested area. We conducted a biometric estimate of net ecosystem production (NEP) in a mature Japanese cedar plantation beneath a flux tower over a 4-year period. Net primary production (NPP) was 7.9 Mg C ha(-1) year(-1) and consisted mainly of tree biomass increment and aboveground litter production. Respiration was calculated as 6.8 (soil) and 3.3 (root) Mg C ha(-1) year(-1). Thus, NEP in the plantation was 4.3 Mg C ha(-1) year(-1). In agreement with the tower-based flux findings, this result suggests that the Japanese cedar plantation was a strong carbon sink. The biometric-based NEP was higher among most other types of Japanese forests studied. Carbon sequestration in the mature plantation was characterized by a larger increment in tree biomass and lower mortality than in natural forests. Land-use change from natural forest to Japanese cedar plantation might, therefore, stimulate carbon sequestration and change the carbon allocation of NPP from an increment in coarse woody debris to an increase in tree biomass.

  3. Achieving a Net Zero Energy Retrofit: Lessons from the University of Hawaii at Manoa

    Energy Technology Data Exchange (ETDEWEB)

    None

    2013-03-01

    The University of Hawaii at Manoa (UHM) partnered with the U.S. Department of Energy (DOE) to develop and implement solutions to retrofit existing buildings to reduce energy consumption by at least 30% as part of DOE’s Commercial Building Partnerships (CBP) Program.

  4. Determination of Energy Use Efficiency of Sesame Production

    OpenAIRE

    BARAN, Mehmet Firat

    2018-01-01

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

  5. Production processes at extremely high energies

    CERN Document Server

    Gastmans, R; Wu, Tai Tsun

    2013-01-01

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

  6. Straw for energy production. Technology - Environment - Economy

    Energy Technology Data Exchange (ETDEWEB)

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

    1998-12-31

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

  7. Biomass production for direct generation of energy

    International Nuclear Information System (INIS)

    1992-01-01

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

  8. Mesozooplankton production, grazing and respiration in the Bay of Bengal: Implications for net heterotrophy

    Digital Repository Service at National Institute of Oceanography (India)

    Fernandes, V.; Ramaiah, N.

    with the Arabian Sea. Contrary to the conventional belief, mesozooplankton grazing impact was up to 83% on primary production (PP). Low PP coupled with very high zooplankton production (70% of PP) along with abundant bacterial production (50% of the PP; Ramaiah et...

  9. Achievement report for fiscal 2000 on the phase II research and development for the hydrogen utilizing international clean energy system technology (WE-NET). Task 1. Investigations and researched on system assessment; 2000 nendo suiso riyo kokusai clean energy system gijutsu (WE-NET) dai 2 ki kenkyu kaihatsu. Task 1. System hyoka ni kansuru chosa kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    This paper describes the achievements in fiscal 2000 from the WE-NET Phase II for Task-1. Technologies drawing attentions relate to fuel cell driven automobiles and hybrid automobiles in the field of utilizing hydrogen derived from reproducible energies and fossil energies, and fuel cell co-generation and micro gas turbine co-generation in the field of electric power generation. Hydrogen reformed from gasoline on board the automobile as the fuel for fuel cell driven automobiles, hydrogen as a by-product of coke furnace off-gas (COG), and reproducible energy hydrogen have the same fuel consumption performance as in the hybrid automobiles. Particularly the COG is low in cost, and has large supply potential. Liquefied hydrogen is as promising as compressed hydrogen in view of the cost for automotive hydrogen supply stations. What has high economic performance as the self-sustaining systems for islands are photovoltaic and wind power generation, and the system using hydrogen as the secondary energy. Since much of the reproducible energies is used for electric power demand in Japan, the by-product hydrogen and the reformed hydrogen in an amount of 9.3 billion Nm{sup 3}/year would take care of majority of the demand in view of the short time period. For a longer time span, hydrogen originated from the reproduced energies in the Pan-Pacific Region should be introduced. (NEDO)

  10. Life cycle energy efficiency and potentials of biodiesel production from palm oil in Thailand

    International Nuclear Information System (INIS)

    Papong, Seksan; Chom-In, Tassaneewan; Noksa-nga, Soottiwan

    2010-01-01

    Biodiesel production from palm oil has been considered one of the most promising renewable resources for transportation fuel in Thailand. The objective of this study was to analyze the energy performance and potential of the palm oil methyl ester (PME) production in Thailand. The PME system was divided into four stages: the oil palm plantation, transportation, crude palm oil (CPO) production, and transesterification into biodiesel. The results showed that the highest fossil-based energy consumption was in the transesterification process, followed by the plantation, transportation, and CPO production. A net energy value and net energy ratio (NER) of 24.0 MJ/FU and 2.5, respectively, revealed that the PME system was quite energy efficient. In addition, if all the by-products from the CPO production (such as empty fruit branches, palm kernel shells, and biogas) were considered in terms of energy sources, the NER would be more than 3.0. The PME can be a viable substitute for diesel and can decrease the need for oil imports. Based on B100 demand in 2008, PME can be substituted for 478 million liters of diesel. Moreover, with palm oil output potential and B5 implementation, it can be substituted for 1134 million liters of diesel. (author)

  11. A Life-Cycle Assessment of Biofuels: Tracing Energy and Carbon through a Fuel-Production System

    Science.gov (United States)

    Krauskopf, Sara

    2010-01-01

    A life-cycle assessment (LCA) is a tool used by engineers to make measurements of net energy, greenhouse gas production, water consumption, and other items of concern. This article describes an activity designed to walk students through the qualitative part of an LCA. It asks them to consider the life-cycle costs of ethanol production, in terms of…

  12. Electrorheology for energy production and conservation

    Science.gov (United States)

    Huang, Ke

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

  13. Energy condensed packaged systems. Composition, production, properties

    Directory of Open Access Journals (Sweden)

    Igor L. Kovalenko

    2015-03-01

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

  14. Energy production and social marginalisation in China

    Energy Technology Data Exchange (ETDEWEB)

    Philip Andrews-Speed; Xin Ma

    2008-05-15

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

  15. High energy photons production in nuclear reactions

    International Nuclear Information System (INIS)

    Nifenecker, H.; Pinston, J.A.

    1990-01-01

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

  16. Rare earth magnets with high energy products

    International Nuclear Information System (INIS)

    Hirosawa, S.; Kaneko, Y.

    1998-01-01

    High energy-products exceeding 430 kj/m 3 (54 MGOe) have been realized on anisotropic permanent magnets based on the Nd 2 Fe 14 B phase, recently. To produce extremely high-energy-product permanent magnets, special processes have been designed in order to realize the minimum oxygen content, the maximum volume fraction of the hard magnetic Nd 2 Fe 14 B phase, the highest orientation of the easy axis of magnetization, and small and homogeneous crystalline grain sizes in the finished magnets. For the powder metallurgical process, special techniques such as low-oxygen fine powder processing and magnetic alignment using pulsed magnetic fields have been developed. It has been shown that a good control of both homogeneity of distribution of constituent phases and the narrowness of the size distribution in the starting powder have great influences on the magnetic energy products. It is emphasized that the recently developed techniques are applicable in a large-scale production, meaning that extremely high-energy-product magnets are available on commercial basis. (orig.)

  17. Getting to Net Zero

    Energy Technology Data Exchange (ETDEWEB)

    2016-09-01

    The technology necessary to build net zero energy buildings (NZEBs) is ready and available today, however, building to net zero energy performance levels can be challenging. Energy efficiency measures, onsite energy generation resources, load matching and grid interaction, climatic factors, and local policies vary from location to location and require unique methods of constructing NZEBs. It is recommended that Components start looking into how to construct and operate NZEBs now as there is a learning curve to net zero construction and FY 2020 is just around the corner.

  18. Asymmetric warming significantly affects net primary production, but not ecosystem carbon balances of forest and grassland ecosystems in northern China.

    Science.gov (United States)

    Su, Hongxin; Feng, Jinchao; Axmacher, Jan C; Sang, Weiguo

    2015-03-13

    We combine the process-based ecosystem model (Biome-BGC) with climate change-scenarios based on both RegCM3 model outputs and historic observed trends to quantify differential effects of symmetric and asymmetric warming on ecosystem net primary productivity (NPP), heterotrophic respiration (Rh) and net ecosystem productivity (NEP) of six ecosystem types representing different climatic zones of northern China. Analysis of covariance shows that NPP is significant greater at most ecosystems under the various environmental change scenarios once temperature asymmetries are taken into consideration. However, these differences do not lead to significant differences in NEP, which indicates that asymmetry in climate change does not result in significant alterations of the overall carbon balance in the dominating forest or grassland ecosystems. Overall, NPP, Rh and NEP are regulated by highly interrelated effects of increases in temperature and atmospheric CO2 concentrations and precipitation changes, while the magnitude of these effects strongly varies across the six sites. Further studies underpinned by suitable experiments are nonetheless required to further improve the performance of ecosystem models and confirm the validity of these model predictions. This is crucial for a sound understanding of the mechanisms controlling the variability in asymmetric warming effects on ecosystem structure and functioning.

  19. Asymmetric warming significantly affects net primary production, but not ecosystem carbon balances of forest and grassland ecosystems in northern China

    Science.gov (United States)

    Su, Hongxin; Feng, Jinchao; Axmacher, Jan C.; Sang, Weiguo

    2015-03-01

    We combine the process-based ecosystem model (Biome-BGC) with climate change-scenarios based on both RegCM3 model outputs and historic observed trends to quantify differential effects of symmetric and asymmetric warming on ecosystem net primary productivity (NPP), heterotrophic respiration (Rh) and net ecosystem productivity (NEP) of six ecosystem types representing different climatic zones of northern China. Analysis of covariance shows that NPP is significant greater at most ecosystems under the various environmental change scenarios once temperature asymmetries are taken into consideration. However, these differences do not lead to significant differences in NEP, which indicates that asymmetry in climate change does not result in significant alterations of the overall carbon balance in the dominating forest or grassland ecosystems. Overall, NPP, Rh and NEP are regulated by highly interrelated effects of increases in temperature and atmospheric CO2 concentrations and precipitation changes, while the magnitude of these effects strongly varies across the six sites. Further studies underpinned by suitable experiments are nonetheless required to further improve the performance of ecosystem models and confirm the validity of these model predictions. This is crucial for a sound understanding of the mechanisms controlling the variability in asymmetric warming effects on ecosystem structure and functioning.

  20. Bio energy: Bio fuel - Properties and Production

    International Nuclear Information System (INIS)

    Wilhelmsen, Gunnar; Martinsen, Arnold Kyrre; Sandberg, Eiliv; Fladset, Per Olav; Kjerschow, Einar; Teslo, Einar

    2001-01-01

    This is Chapter 3 of the book ''Bio energy - Environment, technique and market''. Its main sections are: (1) Definitions and properties, (2) Bio fuel from the forest, (3) Processed bio fuel - briquettes, pellets and powder, (4) Bio fuel from agriculture, (5) Bio fuel from agro industry, (6) Bio fuel from lakes and sea, (7) Bio fuel from aquaculture, (8) Bio fuel from wastes and (9) Hydrogen as a fuel. The exposition largely describes the conditions in Norway. The chapter on energy from the forest includes products from the timber and sawmill industry, the pulp and paper industry, furniture factories etc. Among agricultural sources are straw, energy forests, vegetable oil, bio ethanol, manure

  1. Transforming Global Markets for Clean Energy Products

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    This paper looks at three clean energy product categories: equipment energy efficiency; low-carbon transport, including high-efficiency vehicles and electric/plug-in hybrid electric vehicles (EV/PHEVs); and solar photovoltaic (PV) power. Each section identifies ways to enhance global co-operation among major economies through case studies and examples, and ends with specific suggestions for greater international collaboration on market transformation efforts. An annex with more detailed case studies on energy-efficient electric motors, televisions, external power supplies and compact fluorescent lights is included in the paper.

  2. HAWC Analysis of the Crab Nebula Using Neural-Net Energy Reconstruction

    Science.gov (United States)

    Marinelli, Samuel; HAWC Collaboration

    2017-01-01

    The HAWC (High-Altitude Water-Cherenkov) experiment is a TeV γ-ray observatory located 4100 m above sea level on the Sierra Negra mountain in Puebla, Mexico. The detector consists of 300 water-filled tanks, each instrumented with 4 photomuliplier tubes that utilize the water-Cherenkov technique to detect atmospheric air showers produced by cosmic γ rays. Construction of HAWC was completed in March, 2015. The experiment's wide field of view (2 sr) and high duty cycle (> 95 %) make it a powerful survey instrument sensitive to pulsar wind nebulae, supernova remnants, active galactic nuclei, and other γ-ray sources. The mechanisms of particle acceleration at these sources can be studied by analyzing their energy spectra. To this end, we have developed an event-by-event energy-reconstruction algorithm employing an artificial neural network to estimate energies of primary γ rays. The Crab Nebula, the brightest source of TeV photons, makes an excellent calibration source for this technique. We will present preliminary results from an analysis of the Crab energy spectrum using this new energy-reconstruction method. This work was supported by the National Science Foundation.

  3. FY 1998 annual summary report on International Clean Energy Network Using Hydrogen Conversion (WE-NET) system technology. Subtask 9. Research and evaluation of innovative and leading technologies; 1998 nendo seika hokokusho. Suiso riyo kokusai clean energy system gijutsu (WE-NET) subtask 9 (kakushinteki, sendoteki gijutsu ni kansuru chosa kenkyu)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    In order to make useful suggestions and proposals for the International Clean Energy Network Using Hydrogen Conversion (WE-NET) project and thereby to promote the research and development activities, the innovative and leading technologies have been studied, investigated and evaluated. In FY 1998, a total of 6 proposals were collected, and evaluated to prioritize for the conceptual studies. These are related to methanol-fueled power generation turbine system, conceptual design of high-efficiency production system for high-efficiency solar cell by the 10 GW/y scale production process, investigation of potential of wind power, CO2 recycling methanol fuel cell, investigation of catalysis materials for hydrogen combustion and catalytic combustion systems, development of reversible high-temperature steam electrolysis cell/solid oxide fuel cell by the synthesis from aqueous solutions, and mobile heat recovery hydrogen production system. Promising technologies to be reflected on the WE-NET project were examined, based on the new technologies acquired from the research and investigation so far. As a result, two candidates were selected; hydrogen liquefaction by magnetic refrigeration technology, and catalytic combustion gas turbine. (NEDO)

  4. Water for energy and fuel production

    CERN Document Server

    Shah, Yatish T

    2014-01-01

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

  5. Net fossil energy savings for alternative mixes in various electric supply systems

    International Nuclear Information System (INIS)

    Essam, P.; Stocks, K.J.

    1978-11-01

    The actual and projected electric power station building programs of several countries and regions have been examined to determine what effect the introduction of nuclear power has on fossil fuel usage by the electricity system. It was found that (1) nuclear power leads directly to savings in fossil fuel usage, a larger nuclear component leading to larger savings; (2) individual nuclear stations rapidly wipe out the energy 'debt' incurred during building; and (3) the relatively short periods of consolidation in the early stages of a nation's building program usually prevent the nuclear component from going into energy 'debt'. Assessments of the energy requirements to build and run various types of power station have been made from the available literature

  6. Prototyping Energy Efficient Thermo-Magnetic & Induction Hardening for Heat Treat & Net Shape Forming Applications

    Energy Technology Data Exchange (ETDEWEB)

    Aquil Ahmad

    2012-08-03

    Within this project, Eaton undertook the task of bringing about significant impact with respect to sustainability. One of the major goals for the Department of Energy is to achieve energy savings with a corresponding reduction in carbon foot print. The use of a coupled induction heat treatment with high magnetic field heat treatment makes possible not only improved performance alloys, but with faster processing times and lower processing energy, as well. With this technology, substitution of lower cost alloys for more exotic alloys became a possibility; microstructure could be tailored for improved magnetic properties or wear resistance or mechanical performance, as needed. A prototype commercial unit has been developed to conduct processing of materials. Testing of this equipment has been conducted and results demonstrate the feasibility for industrial commercialization.

  7. Evaluation of the net energy value of glucose (cerelose) and maize starch in diets for rainbow trout (Salmo gairdneri).

    Science.gov (United States)

    Hilton, J W; Atkinson, J L; Slinger, S J

    1987-11-01

    1. Quadruplicate groups of rainbow trout (Salmo gairdneri) (mean body-weight 24.9 g) were reared on six dietary treatments (practical-type diets) in a modified paired-feeding experiment for 12 weeks at 15 degrees to determine the net energy (NE) value of starch and glucose to rainbow trout. 2. Three test diets were prepared to contain (g/kg): 0 supplemented carbohydrate (diet 1), 250 maize starch (diet 2) and 250 glucose (diet 3) and were given ad lib. to the trout with the feeding rate of the glucose- and starch-fed groups being monitored after each feeding. The remaining three treatments involved controlled feeding of the trout with diet 1 at 75% of the feed intake of trout reared on diets 2 and 3, so as to provide the same levels of protein and lipids without carbohydrate, and with diet 2 at 100% of the feed intake of trout reared on diet 3. 3. The difference in the final carcass energy of the ad lib.-fed group and the respective controlled-fed group divided by the amount of dietary glucose or starch energy consumed by the trout is the NE value for that carbohydrate. 4. The determined NE value of glucose was 3.99 kJ/g and starch 2.17 kJ/g, which is 24.6 and 12.6% respectively of the gross energy values of these carbohydrates in rainbow trout. 5. The results indicate that digestible energy and calculated metabolizable energy values for carbohydrates in rainbow trout overestimate the utilizable energy content of the diet.(ABSTRACT TRUNCATED AT 250 WORDS)

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

    Science.gov (United States)

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

    2014-05-01

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

  9. Solar energy; Product information. Zonne-energie; Produktinformatie

    Energy Technology Data Exchange (ETDEWEB)

    Kruisheer, N

    1992-03-20

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

  10. Net primary productivity distribution in the BOREAS region from a process model using satellite and surface data

    Science.gov (United States)

    Liu, J.; Chen, J. M.; Cihlar, J.; Chen, W.

    1999-11-01

    The purpose of this paper is to upscale tower measurements of net primary productivity (NPP) to the Boreal Ecosystem-Atmosphere Study (BOREAS) study region by means of remote sensing and modeling. The Boreal Ecosystem Productivity Simulator (BEPS) with a new daily canopy photosynthesis model was first tested in one coniferous and one deciduous site. The simultaneous CO2 flux measurements above and below the tree canopy made it possible to isolate daily net primary productivity of the tree canopy for model validation. Soil water holding capacity and gridded daily meteorological data for the region were used as inputs to BEPS, in addition to 1 km resolution land cover and leaf area index (LAI) maps derived from the advanced very high resolution radiometer (AVHRR) data. NPP statistics for the various cover types in the BOREAS region and in the southern study area (SSA) and the northern study area (NSA) are presented. Strong dependence of NPP on LAI was found for the three major cover types: coniferous forest, deciduous forest and cropland. Since BEPS can compute total photosynthetically active radiation absorbed by the canopy in each pixel, light use efficiencies for NPP and gross primary productivity could also be analyzed. From the model results, the following area-averaged statistics were obtained for 1994: (1) mean NPP for the BOREAS region of 217 g C m-2 yr-1; (2) mean NPP of forests (excluding burnt areas in the region) equal to 234 g C m-2 yr-1; (3) mean NPP for the SSA and the NSA of 297 and 238 g C m-2 yr-1, respectively; and (4) mean light use efficiency for NPP equal to 0.40, 0.20, and 0.33 g C (MJ APAR)-1 for deciduous forest, coniferous forest, and crops, respectively.

  11. Net primary productivity of subalpine meadows in Yosemite National Park in relation to climate variability

    Science.gov (United States)

    Peggy E. Moore; Jan W. van Wagtendonk; Julie L. Yee; Mitchel P. McClaran; David N. Cole; Neil K. McDougald; Matthew L. Brooks

    2013-01-01

    Subalpine meadows are some of the most ecologically important components of mountain landscapes, and primary productivity is important to the maintenance of meadow functions. Understanding how changes in primary productivity are associated with variability in moisture and temperature will become increasingly important with current and anticipated changes in climate....

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

    International Nuclear Information System (INIS)

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

    2012-01-01

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

  13. A Green Prison: Santa Rita Jail Creeps Towards Zero Net Energy (ZNE)

    Energy Technology Data Exchange (ETDEWEB)

    Marnay, Chris; DeForest, Nicholas; Stadler, Michael; Donadee, Jon; Dierckxsens, Carlos; Mendes, Goncalo; Lai, Judy; Cardoso, Goncalo Ferreira

    2011-03-18

    A large project is underway at Alameda County's twenty-year old 45 ha 4,000-inmate Santa Rita Jail, about 70 km east of San Francisco. Often described as a green prison, it has a considerable installed base of distributed energy resources including a seven-year old 1.2 MW PV array, a four-year old 1 MW fuel cell with heat recovery, and efficiency investments. A current US$14 M expansion will add approximately 2 MW of NaS batteries, and undetermined wind capacity and a concentrating solar thermal system. This ongoing effort by a progressive local government with considerable Federal and State support provides some excellent lessons for the struggle to lower building carbon footprint. The Distributed Energy Resources Customer Adoption Model (DER-CAM) finds true optimal combinations of equipment and operating schedules for microgrids that minimize energy bills and/or carbon emissions without 2 of 12 significant searching or rules-of-thumb prioritization, such as"efficiency first then on-site generation." The results often recommend complex systems, and sensitivities show how policy changes will affect choices. This paper reports an analysis of the historic performance of the PV system and fuel cell, describes the complex optimization applied to the battery scheduling, and shows how results will affect the jail's operational costs, energy consumption, and carbon footprint. DER-CAM is used to assess the existing and proposed DER equipment in its ability to reduce tariff charges.

  14. Biotechnology for energy production. Biotechnologie zur Energieerzeugung

    Energy Technology Data Exchange (ETDEWEB)

    Coombs, J.; Hall, D.O.; Chartier, P.

    1985-01-01

    Starting from the mechanisms of photosynthesis in plants and the environmental parameters influencing growth generally the book deals with the various possibilities for improving productivity in growing biomass. In particular, the modern methods of biotechnology are considered. The investigation submitted was carried through with a view to future energy farms in Europe.

  15. Reactors Save Energy, Costs for Hydrogen Production

    Science.gov (United States)

    2014-01-01

    While examining fuel-reforming technology for fuel cells onboard aircraft, Glenn Research Center partnered with Garrettsville, Ohio-based Catacel Corporation through the Glenn Alliance Technology Exchange program and a Space Act Agreement. Catacel developed a stackable structural reactor that is now employed for commercial hydrogen production and results in energy savings of about 20 percent.

  16. Kaupuni Village: A Closer Look at the First Net-Zero Energy Affordable Housing Community in Hawai'i (Brochure)