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.

Net zero water

CSIR Research Space (South Africa)

Lindeque, M

2013-01-01

Full Text Available the national grid. The unfortunate situation with water is that there is no replacement technology for water. Water can be supplied from many different sources. A net zero energy development will move closer to a net zero water development by reducing...

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

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.

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.

Role of Solar Water Heating in Multifamily Zero Energy Homes

Energy Technology Data Exchange (ETDEWEB)

Aldrich, Robb [Consortium for Advanced Residential Buildings, Norwalk, CT (United States); Williamson, James [Consortium for Advanced Residential Buildings, Norwalk, CT (United States)

2016-04-08

Solar domestic hot water (SDHW) systems have been installed on buildings for decades, but because of relatively high costs they have not achieved significant market penetration in most of the country. As more buildings move towards zero net energy consumption, however, many designers and developers are looking more closely at SDHW. In multifamily buildings especially, SDHW may be more practical for several reasons: 1) When designing for zero net energy consumption, solar water heating may be part of the lowest cost approach to meet water heating loads; 2) Because of better scale, SDHW systems in multifamily buildings cost significantly less per dwelling than in single-family homes; 3) Many low-load buildings are moving away from fossil fuels entirely. SDHW savings are substantially greater when displacing electric resistance water heating; and 4) In addition to federal tax incentives, some states have substantial financial incentives that dramatically reduce the costs (or increase the benefits) of SDHW systems in multifamily buildings. With support from the U.S. DOE Building America program, the Consortium for Advanced Residential Buildings (CARB) worked with a developer in western Massachusetts to evaluate a SDHW system on a 12-unit apartment building. Olive Street Development completed construction in spring of 2014, and CARB has been monitoring performance of the water heating systems since May 2014.

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...

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...

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.

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.

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...

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.

Indirect Solar Water Heating in Single-Family, Zero Energy Ready Homes

Energy Technology Data Exchange (ETDEWEB)

Aldrich, Robb [Consortium for Advanced Residential Buildings, Norwalk, CT (United States)

2016-02-17

Solar water heating systems are not new, but they have not become prevalent in most of the U.S. Most of the country is cold enough that indirect solar thermal systems are required for freeze protection, and average installed cost of these systems is $9,000 to $10,000 for typical systems on single-family homes. These costs can vary significantly in different markets and with different contractors, and federal and regional incentives can reduce these up-front costs by 50% or more. In western Massachusetts, an affordable housing developer built a community of 20 homes with a goal of approaching zero net energy consumption. In addition to excellent thermal envelopes and PV systems, the developer installed a solar domestic water heating system (SDHW) on each home. The Consortium for Advanced Residential Buildings (CARB), a research consortium funded by the U.S. Department of Energy Building America program, commissioned some of the systems, and CARB was able to monitor detailed performance of one system for 28 months.

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

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...

Estimating Solar Energy Potential in Buildings on a Global Level

DEFF Research Database (Denmark)

Petrichenko, Ksenia

2015-01-01

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

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.

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.

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.

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.

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.

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....

DOE Zero Energy Ready Home Case Study: Alliance Green Builders, Casa Aguila

Energy Technology Data Exchange (ETDEWEB)

Pacific Northwest National Laboratory

2017-09-01

Alliance Green Builders built this 3,129-ft2 home in the hills above Ramona, California, to the high-performance criteria of the DOE Zero Energy Ready Home (ZERH) program. The home should perform far better than net zero thanks to a super-efficient building shell, a wind turbine, three suntracking solar photovoltaic arrays, and solar thermal water heating.

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.

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

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

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.

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.

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.

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

NPC Based Design Optimization for a Net Zero Office Building in Hot Climates with PV Panels as Shading Device

Directory of Open Access Journals (Sweden)

Muhammad Zubair

2018-05-01

Full Text Available Hot areas of the world receive a high amount of solar radiation. As a result, buildings in those areas consume more energy to maintain a comfortable climate for their inhabitants. In an effort to design net-zero energy building in hot climates, PV possesses the unique advantage of generating electrical energy while protecting the building from solar irradiance. In this work, to form a net-zero energy building (NZEB, renewable resources such as solar and wind available onsite for an existing building have been analyzed in a hot climate location. PV and wind turbines in various configurations are studied to form a NZEB, where PV-only systems offer better performance than Hybrid PV Wind systems, based on net present cost (NPC. The self-shading losses in PV placed on rooftop areas are analyzed by placing parallel arrays of PV modules at various distances in between them. The effect on building cooling load by rooftop PV panels as shading devices is investigated. Furthermore, self-shading losses of PV are compared by the savings in cooling loads using PV as shading. In the case study, 12.3% saving in the cooling load of the building is observed when the building rooftop is completed shaded by PV panels; annual cooling load decreased from 3.417 GWh to 2.996 GWh, while only 1.04% shaded losses are observed for fully shaded (FS buildings compared to those with no shading (NS, as PV generation decreases from 594.39 kWh/m2 to 588.21 kWh/m2. The net present cost of the project has been decreased from US$4.77 million to US$4.41 million by simply covering the rooftop completely with PV panels, for a net-zero energy building.

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...

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.

Zero energy homes – Are they economically viable?

International Nuclear Information System (INIS)

Berry, Stephen; Davidson, Kathryn

2015-01-01

Whilst net zero energy homes are espoused in many policy circles, and many bespoke examples have been constructed to demonstrate their technical feasibility, there is a scarcity of evidence demonstrating such a standard would be economically rational, particularly for large scale housing development where orientation and aspect may not always be optimal. Drawing on energy monitoring evidence and construction economics associated with a nearly zero energy housing estate in Adelaide, Australia, this paper explores the economic feasibility of the net zero energy home policy in warm temperate climates. The results demonstrate that using economic tools and assumptions typically applied for building energy regulatory policy changes, net societal economic benefits significantly outweigh costs. The clear economic outcomes, combined with expected health and productivity benefits from improved levels of thermal comfort, should provide security to policy makers to progress home energy standards towards net zero energy performance. -- Highlights: •The concept of net zero energy homes is examined for economic viability. •Evidence is collected from a near net zero energy housing estate. •Conservative results show that societal benefits outweigh costs. •Significant additional benefits gained from net zero energy homes

Aspinall Courthouse: GSA's Historic Preservation and Net-Zero Renovation Case Study

Energy Technology Data Exchange (ETDEWEB)

Chang, R.; Hayter, S.; Hotchkiss, E.; Pless, S.; Sielcken, J.; Smith-Larney, C.

2014-10-01

The federal government is mandated with improving efficiency of buildings, incorporating renewable energy, and achieving net-zero energy operations where possible. These challenges led GSA to consider aligning historic preservation renovations with net-zero energy goals. The Wayne N. Aspinall Federal Building and U.S. Courthouse (Aspinall Courthouse), in Grand Junction, Colorado, is an example of a renovation project that aimed to accomplish both historic preservation and net-zero energy goals.

Investigations of a Cost-Optimal Zero Energy Balance

DEFF Research Database (Denmark)

Marszal, Anna Joanna; Nørgaard, Jesper; Heiselberg, Per

2012-01-01

The Net Zero Energy Building (Net ZEB) concept is worldwide recognised as a promising solution for decreasing buildings’ energy use. Nevertheless, a consistent definition of the Net ZEB concept is constantly under discussion. One of the points on the Net ZEB agenda is the zero energy balance...... and taken a view point of private building owner to investigate what types of energy uses should be included in the cost-optimal zero energy balance. The analysis is conducted for five renewable energy supply systems and five user profiles with a study case of a multi-storey residential Net ZEB. The results...... have indicated that with current energy prices and technology, a cost-optimal Net ZEB zero energy balance accounts for only the building related energy use. Moreover, with high user related energy use is even more in favour of excluding appliances from the zero energy balance....

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

Getting to zero - Experiences of designing and monitoring a zero-energy-building: The Science House in Minnesota

Energy Technology Data Exchange (ETDEWEB)

Steinbock, Jason; McDougall, Tom; Eijadi, David; Weier, Jeff [The Weidt Group, Minnetonka, MN (United States)

2005-07-01

The challenge of the Science House at the Science Museum of Minnesota was to create habitable, cold climate architecture that would result in a zero net energy building. The team used science to exert an authoritative influence to resolve design conflicts-at the intersections of functionality, aesthetics and performance. The team needed to significantly reduce annual energy consumption beginning with expectations of use and architectural form. Ultimately, renewable generation would be needed. The defining question became 'how much building and power generation can we build with the given budget?' The resulting building utilizes passive solar design, daylighting, ground source heat pumps and photovoltaic (PV) panels as the major design strategies. This poster documents the predicted energy use and actual monitored performance. It shows the extent of load reduction achieved with passive solar design. A challenge for getting to 'real zero' is the difference between expected performance and actual building performance. This poster illustrates how measured data is used to trace the causes to unexpected equipment performance, heat pump behaviour and off-line PV panels. Assumptions regarding occupancy and building use during the design phase often differ from their actual use; this makes operating a building for zero energy an additional challenge above and beyond designing one. Overall, the actual building is exceeding the design team's goals, using on average 59 kWh/m{sup 2} annually and generating 80 kWh/m{sup 2} to exceed even the zero net energy goals.

Development of the smart photovoltaic system blind and its impact on net-zero energy solar buildings using technical-economic-political analyses

International Nuclear Information System (INIS)

Koo, Choongwan; Hong, Taehoon; Jeong, Kwangbok; Ban, Cheolwoo; Oh, Jeongyoon

2017-01-01

It is expected that the rooftop photovoltaic (PV) systems can realize net-zero energy solar buildings (nZESBs), but it is not enough by itself. To realize 100% of nZESBs, the smart photovoltaic system blind (SPSB) was proposed to generate electricity in the PV system and to reduce indoor cooling demands through the shading effect in the blind system. Before its implementation, this study aims to investigate the impact of the proposed SPSB on nZESBs, which is conducted in three ways (i.e., technical, economic, and political analyses). The detailed results can be summarized as follows: (i) technical analysis: when applying the SPSB_C_I_G_S_&_2_-_a_x_i_s (which represents the SPSB with the copper-indium-gallium-selenide (CIGS) PV panel and the two-axis tracking system), its energy self-sufficiency rate was determined to be 1.25–2.31 times superior to other alternatives; (ii) economic analysis: in terms of the NPV_2_5 (net present value at year 25), SPSB_C_I_G_S_&_2_-_a_x_i_s was determined to be 1.41–2.97 times superior to others; in terms of the SIR_2_5 (savings-to-investment ratio at year 25), 1.14–1.26 times; and in terms of the break-even point, 1.4–3.0 years; and (iii) political analysis: the grid-connected utilization plan including solar renewable energy certificates (GC_i_n_c_l_._S_R_E_C plan) was determined to improve the economic profitability of the proposed SPSB. - Highlights: • The smart photovoltaic system blind was developed as prototype model in four ways. • The SPSB_C_I_G_S_&_2_-_a_x_i_s was determined to be superior to other prototype models. • A holistic analysis was conducted to evaluate the impact of the SPSB on nZESBs. • When implementing the GC_i_n_c_l_._S_R_E_C plan, the economic profitability was maximized. • Results showed the NPV_2_5 (US$2.37/m"2), SIR_2_5 (2.97 times), and BEP (7.6 years).

DOE Zero Energy Ready Home Case Study: Garbett Homes, Herriman, Utah

Energy Technology Data Exchange (ETDEWEB)

none,

2013-09-01

As the first net zero-energy production home certified in Utah, this house incorporates two 94% efficient tankless water heaters and two roof-mounted solar panels that preheat the home's water supply. This home won a 2013 Housing Innovation Award in the production builder category.

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.

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.

Solar Assisted Ground Source Heat Pump Performance in Nearly Zero Energy Building in Baltic Countries

Science.gov (United States)

Januševičius, Karolis; Streckienė, Giedrė

2013-12-01

In near zero energy buildings (NZEB) built in Baltic countries, heat production systems meet the challenge of large share domestic hot water demand and high required heating capacity. Due to passive solar design, cooling demand in residential buildings also needs an assessment and solution. Heat pump systems are a widespread solution to reduce energy use. A combination of heat pump and solar thermal collectors helps to meet standard requirements and increases the share of renewable energy use in total energy balance of country. The presented paper describes a simulation study of solar assisted heat pump systems carried out in TRNSYS. The purpose of this simulation was to investigate how the performance of a solar assisted heat pump combination varies in near zero energy building. Results of three systems were compared to autonomous (independent) systems simulated performance. Different solar assisted heat pump design solutions with serial and parallel solar thermal collector connections to the heat pump loop were modelled and a passive cooling possibility was assessed. Simulations were performed for three Baltic countries: Lithuania, Latvia and Estonia.

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

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....

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.

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

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.

Solar Sustainable Heating, Cooling and Ventilation of a Net Zero Energy House

DEFF Research Database (Denmark)

Kazanci, Ongun Berk; Skrupskelis, Martynas; Olesen, Bjarne W.

Present work addresses the heating, cooling and ventilation concerns of the Technical University of Denmark’s house, Fold, for Solar Decathlon Europe 2012. Various innovative approaches are investigated, namely, utilization of ground, photo-voltaic/thermal (PV/T) panels and phase change materials...... (PCM). The ground heat exchanger acts as the heat sink and heat source for cooling and heating seasons, respectively. Free cooling enables the same cooling effect to be delivered with 8% of the energy consumption of a representative chiller. The heating and cooling needs of the house are addressed...... by the embedded pipes which are coupled with the ground. Ventilation is mainly used to control the humidity and to remove sensory and chemical pollution. PV/T panels enable the house to be a “plus” energy house. PV/T also yields to a solar fraction of 63% and 31% for Madrid and Copenhagen, respectively...

Achieving a Net Zero Energy Retrofit - In a humid, temperate climate: Lessons from the University of Hawai'i at Manoa

Energy Technology Data Exchange (ETDEWEB)

Regnier, Cindy [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Robinson, Alastair [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2013-06-01

The University of Hawaii at Manoa (UHM) partnered with the US Department of Energy (DOE) to develop and implement solutions to retrofit exiting buildings to reduce energy consumption by at least 30% as part of DOE’s Commercial Building Partnerships (CBP) Program.1 Kuykendall Hall, located on the UHM campus in Honolulu, was the focus of a CBP analysis and design collaboration among the University of Hawai’i, their consultants, and Lawrence Berkeley National Laboratory (LBNL). Kuykendall Hall consists of two 1960s-era wings – a four-story wing containing classrooms, and a seven-story tower containing offices – with a total floor area of approximately 76,000 square feet (ft2). The retrofit design, which uses local prevailing winds to aid ventilation and cooling and incorporates envelope and lighting elements that reduce the need for cooling, was initially on track to use about 50% less energy than the current building, exceeding the CBP’s 30% savings goal. With the addition of building-mounted solar electric panels, the retrofitted building is projected to achieve net-zero annual energy use. Achieving net-zero energy addressed an emerging challenge to the university – how to lower energy usage and reduce dependence on imported fossil fuel in the face of already-high energy prices that are forecast to double by 2040. Not only will the retrofit dramatically reduce Kuykendall Hall’s annual energy costs, but the project lays the groundwork for new campus policies and processes and low-energy design approaches and is building a campus knowledge base on low-energy practices. This project is a model of integrated design and building delivery that will be replicated in future projects on the campus.

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.

Management of solar energy in microgrids using IoT-based dependable control

OpenAIRE

Phung, Manh Duong; De La Villefromoy, Michel; Ha, Quang

2017-01-01

Solar energy generation requires efficient monitoring and management in moving towards technologies for net-zero energy buildings. This paper presents a dependable control system based on the Internet of Things (IoT) to control and manage the energy flow of renewable energy collected by solar panels within a microgrid. Data for optimal control include not only measurements from local sensors but also meteorological information retrieved in real-time from online sources. For system fault toler...

Kaupuni Village: A Closer Look at the First Net-Zero Energy Affordable Housing Community in Hawai'i (Brochure)

Energy Technology Data Exchange (ETDEWEB)

2012-05-01

This is the first of four Hawaii Clean Energy Initiative community brochures focused on HCEI success stories. This brochure focuses on the first LEED Platinum net-zero energy affordable housing community in Hawaii. Our lead NREL contact for HCEI is Ken Kelly.

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

Indirect Solar Water Heating in Single-Family, Zero Energy Ready Homes

Energy Technology Data Exchange (ETDEWEB)

Aldrich, Robb [Steven Winters Associates, Inc., Norwalk, CT (United States)

2016-02-01

In western Massachusetts, an affordable housing developer built a community of 20 homes with the goal of approaching zero energy consumption. In addition to excellent thermal envelopes and photovoltaic systems, the developer installed a solar domestic hot water (SDHW) system on each home. The Consortium for Advanced Residential Buildings (CARB), a U.S. Department of Energy Building America research team, commissioned some of the systems, and CARB was able to monitor detailed performance of one system for 28 months.

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

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

Solar-assisted low energy dwellings

Energy Technology Data Exchange (ETDEWEB)

Esbensen, T V

1980-02-01

The Zero Energy House Group was formed as a subproject of the CCMS Solar Energy Pilot Study in 1974 by seven participating countries experimenting with solar-assisted low-energy dwellings for temperate and northern European climatic conditions. A Zero Energy House is one in which solar energy is used to meet the reduced energy needs of buildings incorporating various thermal energy conservation features. This final report of the Zero Energy House Group includes brief descriptions of 13 major low-energy dwellings in the participating CCMS countries. An overall assessment of the state-of-the-art in solar-assisted low-energy dwellings is also included.

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.

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.

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.

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

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...

Near zero energy homes – What do users think?

International Nuclear Information System (INIS)

Berry, Stephen; Whaley, David; Davidson, Kathryn; Saman, Wasim

2014-01-01

With policy directions firmly moving towards net zero energy homes, what do we know about the perceptions and experiences of households who already live in homes at or near that standard? The research sets out to determine whether householders believe these buildings are thermally comfortable, and if they feel confident operating the smart technologies that help achieve the net zero energy outcome? Combining interviews from 25 households and monitored energy data from over 50 near zero energy homes, this paper examines the validity of this policy goal from the building user perspective. The evidence shows households attain high levels of thermal comfort, enjoy lower energy bills, and believe their behaviour has been influenced by the building and its energy systems. Yet many remain concerned that the building industry is unable to produce homes that maintain thermal comfort in all spaces and all seasons. The residents have also identified significant issues in the reliability and usability of the energy technologies. Whilst the policy appears valid from the end-user perspective, the case study highlights the substantial task ahead for policy makers to establish suitable commissioning and compliance processes, and develop effective energy rating tools on the path to zero energy homes. - Highlights: • The policy concept of zero energy homes is examined from the user perspective. • Evidence is collected from a near net zero energy housing estate. • Results show that the homes are highly comfortable and valued by households. • Seasonal differences in the delivery of thermal comfort are found. • Significant design problems and technology reliability issues are identified

Solar Irradiance & On Grid Solar Power Systems with Net Metering in Pakistan

Directory of Open Access Journals (Sweden)

Haleema Qamar

2016-06-01

Full Text Available This paper presents a case study of solar irradiance and scope of on-grid solar power systems with net-metering in Pakistan. Detailed analysis of solar irradiance in Pakistan is being carried out by developing the dedicated solar excel sheets. The need of on grid solar power systems for the present energy crisis in developing countries like Pakistan is also discussed. It also presents the inclination of many countries especially USA and Europe towards it. Identification of barriers for implementing on grid net metered solar power systems in Pakistan along with solutions of these barriers is carried out.

Pusat Tenaga Malaysia's Zero Energy Office (ZEO) Building

DEFF Research Database (Denmark)

Tang, C.K.; Reimann, Gregers Peter; Kristensen, Poul Erik

Technical Review of the Zero Energy Office building in Malaysia. The building, which has an energy index of 50 kWh/m2/year, reaches a net annual energy of zero through the use of building integrated photovoltaic panels. For reference, ordinary offices in Malaysia consume 200 - 300 kWh/m2/year...

Design and optimization of zero-energy-consumption based solar energy residential building systems

Science.gov (United States)

Zheng, D. L.; Yu, L. J.; Tan, H. W.

2017-11-01

Energy consumption of residential buildings has grown fast in recent years, thus raising a challenge on zero energy residential building (ZERB) systems, which aim at substantially reducing energy consumption of residential buildings. Thus, how to facilitate ZERB has become a hot but difficult topic. In the paper, we put forward the overall design principle of ZERB based on analysis of the systems’ energy demand. In particular, the architecture for both schematic design and passive technology is optimized and both energy simulation analysis and energy balancing analysis are implemented, followed by committing the selection of high-efficiency appliance and renewable energy sources for ZERB residential building. In addition, Chinese classical residential building has been investigated in the proposed case, in which several critical aspects such as building optimization, passive design, PV panel and HVAC system integrated with solar water heater, Phase change materials, natural ventilation, etc., have been taken into consideration.

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.

Zero Energy Communities with Central Solar Plants using Liquid Desiccants and Local Storage: Preprint

Energy Technology Data Exchange (ETDEWEB)

Burch, J.; Woods, J.; Kozubal, E.; Boranian, A.

2012-08-01

The zero energy community considered here consists of tens to tens-of-thousands of residences coupled to a central solar plant that produces all the community's electrical and thermal needs. A distribution network carries fluids to meet the heating and cooling loads. Large central solar systems can significantly reduce cost of energy vs. single family systems, and they enable economical seasonal heat storage. However, the thermal distribution system is costly. Conventional district heating/cooling systems use a water/glycol solution to deliver sensible energy. Piping is sized to meet the peak instantaneous load. A new district system introduced here differs in two key ways: (i) it continuously distributes a hot liquid desiccant (LD) solution to LD-based heating and cooling equipment in each home; and (ii) it uses central and local storage of both LD and heat to reduce flow rates to meet average loads. Results for piping sizes in conventional and LD thermal communities show that the LD zero energy community reduces distribution piping diameters meeting heating loads by {approx}5X and meeting cooling loads by {approx}8X for cooling, depending on climate.

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...

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.

Lorentz invariance and the zero-point stress-energy tensor

OpenAIRE

Visser, Matt

2016-01-01

Some 65 years ago (1951) Wolfgang Pauli noted that the net zero-point energy density could be set to zero by a carefully fine-tuned cancellation between bosons and fermions. In the current article I will argue in a slightly different direction: The zero-point energy density is only one component of the zero-point stress energy tensor, and it is this tensor quantity that is in many ways the more fundamental object of interest. I shall demonstrate that Lorentz invariance of the zero-point stres...

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.

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.

Zero Energy Schools--Beyond Platinum

Science.gov (United States)

Hutton, Paul C.

2011-01-01

One of the fastest growing trends in school design is Net Zero Energy Schools. There are now at least a dozen or more schools completed or in construction that have achieved, or have committed to, this incredible level of energy efficiency. In this article, the author examines this trend and take a brief look at some of the exemplary projects that…

Campus Energy Approach, REopt Overview, and Solar for Universities

Energy Technology Data Exchange (ETDEWEB)

Elgqvist, Emma M [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Van Geet, Otto D [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2017-10-19

This presentation gives an overview of the climate neutral research campus framework for reducing energy use and meeting net zero electricity on research campuses. It gives an overview of REopt and the REopt Lite web tool, which can be used to evaluate cost optimal sizes of behind the meter PV and storage. It includes solar PV installation trends at universities and case studies for projects implemented on university campuses.

Setting a price for solar net-metering in California

OpenAIRE

Knezevic, Laura M

2014-01-01

Net-metering programs are an effective policy tool for promoting investment in solar photovoltaics, yet little attention has been paid to the rate at which excess energy generation is credited until recently. Like most States, California customers who participate in net-metering receive a credit for excess generation at the current retail rate for electricity. This buy-back rate does not take into account the value of solar energy to the utility or the costs to the customer of purchasing an...

An Exploration of the Relationship between Improvements in Energy Efficiency and Life-Cycle Energy and Carbon Emissions using the BIRDS Low-Energy Residential Database.

Science.gov (United States)

Kneifel, Joshua; O'Rear, Eric; Webb, David; O'Fallon, Cheyney

2018-02-01

To conduct a more complete analysis of low-energy and net-zero energy buildings that considers both the operating and embodied energy/emissions, members of the building community look to life-cycle assessment (LCA) methods. This paper examines differences in the relative impacts of cost-optimal energy efficiency measure combinations depicting residential buildings up to and beyond net-zero energy consumption on operating and embodied flows using data from the Building Industry Reporting and Design for Sustainability (BIRDS) Low-Energy Residential Database. Results indicate that net-zero performance leads to a large increase in embodied flows (over 40%) that offsets some of the reductions in operational flows, but overall life-cycle flows are still reduced by over 60% relative to the state energy code. Overall, building designs beyond net-zero performance can partially offset embodied flows with negative operational flows by replacing traditional electricity generation with solar production, but would require an additional 8.34 kW (18.54 kW in total) of due south facing solar PV to reach net-zero total life-cycle flows. Such a system would meet over 239% of operational consumption of the most energy efficient design considered in this study and over 116% of a state code-compliant building design in its initial year of operation.

Supervisory Control of Loads and Energy Storage in Next-Generation Zero Energy Buildings

Energy Technology Data Exchange (ETDEWEB)

Kung, Feitau [National Renewable Energy Lab. (NREL), Golden, CO (United States); Frank, Stephen [National Renewable Energy Lab. (NREL), Golden, CO (United States); Scheib, Jennifer [National Renewable Energy Lab. (NREL), Golden, CO (United States); Bernal Heredia, Willy [National Renewable Energy Lab. (NREL), Golden, CO (United States); Pless, Shanti [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-09-01

A zero energy building (ZEB)—also known as a net zero energy or zero net energy building—is a building that exports as much renewable energy as the total energy it imports from other sources on an annual basis (DOE 2015). Large-scale and commercially viable ZEBs are now in the marketplace, and they are expected to become a larger share of the commercial building footprint as government and private sector policies continue to promote the development of buildings that produce more on-site energy than they use. However, the load profiles of ZEBs are currently perceived by electric utilities to be unfavorable and unpredictable. As shown in Figure ES-1, ZEB load profiles can have abrupt changes in magnitude, at times switching rapidly between exporting and importing electricity. This is a challenge for utilities, which are responsible for constantly balancing electricity supply and demand across the grid. Addressing these concerns will require new strategies and tools.

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.

Neutron transport assembly calculation with non-zero net current boundary condition

International Nuclear Information System (INIS)

Jo, Chang Keun

1993-02-01

Fuel assembly calculation for the homogenized group constants is one of the most important parts in the reactor core analysis. The homogenized group constants of one a quarter assembly are usually generated for the nodal calculation of the reactor core. In the current nodal calculation, one or a quarter of the fuel assembly corresponds to a unit node. The homogenized group constant calculation for a fuel assembly proceeds through cell spectrum calculations, group condensation and cell homogenization calculations, two dimensional fuel assembly calculation, and then depletion calculations of fuel rods. To obtain the assembly wise homogenized group constants, the two dimensional transport calculation is usually performed. Most codes for the assembly wise homogenized group constants employ a zero net current boundary condition. CASMO-3 is such a code that is in wide use. The zero net current boundary condition is plausible and valid in an infinite reactor composed of the same kind of assemblies. However, the reactor is finite and the core is constructed by different kinds of assemblies. Hence, the assumption of the zero net current boundary condition is not valid in the actual reactor. The objective of this study is to develop a homogenization methodology that can treat any actual boundary condition, i.e. non-zero net current boundary condition. In order to treat the non-zero net current boundary condition, we modify CASMO-3. For the two-dimensional treatment in CASMO-3, a multigroup integral transport routine based on the method of transmission probability is used. The code performs assembly calculation with zero net current boundary condition. CASMO-3 is modified to consider the inhomogeneous source at the assembly boundary surface due to the non-zero net current. The modified version of CASMO-3 is called CASMO-3M. CASMO-3M is applied to several benchmark problems. In order to obtain the inhomogeneous source, the global calculation is performed. The local calculation

Defining nearly zero-energy housing in Belgium and the Netherlands

Energy Technology Data Exchange (ETDEWEB)

Mlecnik, E. [OTB Research Institute for the Built Environment, Delft University of Technology, P.O. Box 5030, 2600 GA Delft (Netherlands)

2012-08-15

Europe expects the housing sector to evolve towards 'nearly zero-energy' dwellings. Meanwhile, general terms and research, marketing and legal definitions considering such dwellings have already been introduced. Appraisal of existing definitions is now needed for further policy development. This paper examines what nearly zero-energy terms can be expected to be adopted in Belgium and the Netherlands. The research method uses an interview method based on innovation diffusion theory. The analysis traces the regional adoption trajectory of relevant definitions and examines the opportunities and barriers for the inclusion of existing definitions in regional energy policy. The analysis shows that - whilst international prominence of the terms 'net zero energy' and 'net zero carbon', in addition to 'low energy' and 'passive house', is observed - in Belgium and the Netherlands 'passive house' and 'energy neutral' are preferred. The research findings indicate that the adoption of already existing definitions for nearly zero-energy houses will depend on the region and can prove a very complex process with several conflicting issues. Terms should be clearly defined and used at all political and marketing levels. It is recommended to enhance the relative advantage, demonstrability, visibility and compatibility of favoured definitions by policy initiatives.

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.

Mineralizing urban net-zero water treatment: Phase II field results and design recommendations

Science.gov (United States)

Net-zero water (NZW) systems, or water management systems achieving high recycling rates and low residuals generation so as to avoid water import and export, can also conserve energy used to heat and convey water, while economically restoring local eco-hydrology. However, design ...

A Solar Heating and Cooling System in a Nearly Zero-Energy Building: A Case Study in China

Directory of Open Access Journals (Sweden)

Zhifeng Sun

2017-01-01

Full Text Available The building sector accounts for more than 40% of the global energy consumption. This consumption may be lowered by reducing building energy requirements and using renewable energy in building energy supply systems. Therefore, a nearly zero-energy building, incorporating a solar heating and cooling system, was designed and built in Beijing, China. The system included a 35.17 kW cooling (10-RT absorption chiller, an evacuated tube solar collector with an aperture area of 320.6 m2, two hot-water storage tanks (with capacities of 10 m3 and 30 m3, respectively, two cold-water storage tanks (both with a capacity of 10 m3, and a 281 kW cooling tower. Heat pump systems were used as a backup. At a value of 25.2%, the obtained solar fraction associated with the cooling load was close to the design target of 30%. In addition, the daily solar collector efficiency and the chiller coefficient of performance (COP varied from 0.327 to 0.507 and 0.49 to 0.70, respectively.

Net-zero Building Cluster Simulations and On-line Energy Forecasting for Adaptive and Real-Time Control and Decisions

Science.gov (United States)

Li, Xiwang

Buildings consume about 41.1% of primary energy and 74% of the electricity in the U.S. Moreover, it is estimated by the National Energy Technology Laboratory that more than 1/4 of the 713 GW of U.S. electricity demand in 2010 could be dispatchable if only buildings could respond to that dispatch through advanced building energy control and operation strategies and smart grid infrastructure. In this study, it is envisioned that neighboring buildings will have the tendency to form a cluster, an open cyber-physical system to exploit the economic opportunities provided by a smart grid, distributed power generation, and storage devices. Through optimized demand management, these building clusters will then reduce overall primary energy consumption and peak time electricity consumption, and be more resilient to power disruptions. Therefore, this project seeks to develop a Net-zero building cluster simulation testbed and high fidelity energy forecasting models for adaptive and real-time control and decision making strategy development that can be used in a Net-zero building cluster. The following research activities are summarized in this thesis: 1) Development of a building cluster emulator for building cluster control and operation strategy assessment. 2) Development of a novel building energy forecasting methodology using active system identification and data fusion techniques. In this methodology, a systematic approach for building energy system characteristic evaluation, system excitation and model adaptation is included. The developed methodology is compared with other literature-reported building energy forecasting methods; 3) Development of the high fidelity on-line building cluster energy forecasting models, which includes energy forecasting models for buildings, PV panels, batteries and ice tank thermal storage systems 4) Small scale real building validation study to verify the performance of the developed building energy forecasting methodology. The outcomes of

Designing of zero energy office buildings in hot arid climate

Energy Technology Data Exchange (ETDEWEB)

Abdel-Gwad, Mohamed

2011-07-01

The designing of office buildings by using large glass areas to have a transparent building is an attractive approach in the modern office building architecture. This attitude increases the energy demand for cooling specially in the hot arid region which has long sun duration time, while the use of small glazing areas increases the energy demand for lighting. The use of uncontrolled natural ventilation increases the rate of hot ambient air flow which increases the building energy demand for cooling. At the same time, the use of mechanical ventilation to control the air change rate may increase the energy demand for fans. Some ideas such as low energy design concept are introduced for improving the building energy performance and different rating systems have been developed such as LEED, BREEAM and DGNB for evaluating building energy performance system. One of the new ideas for decreasing the dependence on fossil fuels and improving the use of renewable energy is the net zero-energy building concept in which the building generates enough renewable energy on site to equal or exceed its annual energy use. This work depends on using the potentials of mixing different energy strategies such as hybrid ventilation strategy, passive night cooling, passive chilled ceiling side by side with the integrating of photovoltaic modules into the building facade to produce energy and enrich the architectural aesthetics and finally reaching the Net Zero Energy Building. There are different definitions for zero energy buildings, however in this work the use of building-integrated Photovoltaic (BIPV) to provide the building with its annual energy needs is adopted, in order to reach to a Grid-Connected Net-Zero Energy Office Building in the hot arid desert zone represented by Cairo, Egypt. (orig.)

A transitioning Arctic surface energy budget: the impacts of solar zenith angle, surface albedo and cloud radiative forcing

Energy Technology Data Exchange (ETDEWEB)

Sedlar, Joseph; Tjernstroem, Michael; Leck, Caroline [Stockholm University, Department of Meteorology, Stockholm (Sweden); Mauritsen, Thorsten [Max-Planck-Institute for Meteorology, Hamburg (Germany); Shupe, Matthew D.; Persson, P.O.G. [University of Colorado, NOAA-ESRL-PSD, Boulder, CO (United States); Brooks, Ian M.; Birch, Cathryn E. [University of Leeds, School of Earth and Environment, Leeds (United Kingdom); Sirevaag, Anders [University of Bergen, Bjerknes Center for Climate Research, Bergen (Norway); Nicolaus, Marcel [Norwegian Polar Institute, Tromsoe (Norway); Alfred Wegener Institute for Polar and Marine Research, Bremerhaven (Germany)

2011-10-15

Snow surface and sea-ice energy budgets were measured near 87.5 N during the Arctic Summer Cloud Ocean Study (ASCOS), from August to early September 2008. Surface temperature indicated four distinct temperature regimes, characterized by varying cloud, thermodynamic and solar properties. An initial warm, melt-season regime was interrupted by a 3-day cold regime where temperatures dropped from near zero to -7 C. Subsequently mean energy budget residuals remained small and near zero for 1 week until once again temperatures dropped rapidly and the energy budget residuals became negative. Energy budget transitions were dominated by the net radiative fluxes, largely controlled by the cloudiness. Variable heat, moisture and cloud distributions were associated with changing air-masses. Surface cloud radiative forcing, the net radiative effect of clouds on the surface relative to clear skies, is estimated. Shortwave cloud forcing ranged between -50 W m{sup -2} and zero and varied significantly with surface albedo, solar zenith angle and cloud liquid water. Longwave cloud forcing was larger and generally ranged between 65 and 85 W m{sup -2}, except when the cloud fraction was tenuous or contained little liquid water; thus the net effect of the clouds was to warm the surface. Both cold periods occurred under tenuous, or altogether absent, low-level clouds containing little liquid water, effectively reducing the cloud greenhouse effect. Freeze-up progression was enhanced by a combination of increasing solar zenith angles and surface albedo, while inhibited by a large, positive surface cloud forcing until a new air-mass with considerably less cloudiness advected over the experiment area. (orig.)

Evaluating the Life Cycle Environmental Benefits and Trade-Offs of Water Reuse Systems for Net-Zero Buildings.

Science.gov (United States)

Hasik, Vaclav; Anderson, Naomi E; Collinge, William O; Thiel, Cassandra L; Khanna, Vikas; Wirick, Jason; Piacentini, Richard; Landis, Amy E; Bilec, Melissa M

2017-02-07

Aging water infrastructure and increased water scarcity have resulted in higher interest in water reuse and decentralization. Rating systems for high-performance buildings implicitly promote the use of building-scale, decentralized water supply and treatment technologies. It is important to recognize the potential benefits and trade-offs of decentralized and centralized water systems in the context of high-performance buildings. For this reason and to fill a gap in the current literature, we completed a life cycle assessment (LCA) of the decentralized water system of a high-performance, net-zero energy, net-zero water building (NZB) that received multiple green building certifications and compared the results with two modeled buildings (conventional and water efficient) using centralized water systems. We investigated the NZB's impacts over varying lifetimes, conducted a break-even analysis, and included Monte Carlo uncertainty analysis. The results show that, although the NZB performs better in most categories than the conventional building, the water efficient building generally outperforms the NZB. The lifetime of the NZB, septic tank aeration, and use of solar energy have been found to be important factors in the NZB's impacts. While these findings are specific to the case study building, location, and treatment technologies, the framework for comparison of water and wastewater impacts of various buildings can be applied during building design to aid decision making. As we design and operate high-performance buildings, the potential trade-offs of advanced decentralized water treatment systems should be considered.

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

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.

Zero energy buildings and mismatch compensation factors

DEFF Research Database (Denmark)

Lund, Henrik; Marszal, Anna Joanna; Heiselberg, Per

2011-01-01

This paper takes an overall energy system approach to analysing the mismatch problem of zero energy and zero emission buildings (ZEBs). The mismatch arises from hourly differences in energy production and consumption at the building level and results in the need for exchange of electricity via...... the public grid even though the building has an annual net-exchange of zero. This paper argues that, when looked upon from the viewpoint of the overall electricity supply system, a mismatch can be both negative and positive. Moreover, there are often both an element of levelling out mismatches between...... of the energy production unit. Based on historical data for the electricity supply area in western Denmark, this paper makes a first attempt to quantify mismatch compensation factors. The results indicate that such compensation factors are a little below one for buildings with photovoltaics (PV) and a little...

Net Zero Pilot Program Lights the Path to Big Savings in Guam

Energy Technology Data Exchange (ETDEWEB)

PNNL

2016-11-03

Case study describes how the Army Reserve 9th Mission Support Command (MSC) reduced lighting energy consumption by 62% for a total savings of 125,000 kWh and more than $50,000 per year by replacing over 400 fluorescent troffers with 36 W LED troffers. This project was part of the Army Reserve Net Zero Pilot Program, initiated in 2013, to reduce energy and water consumption, waste generation, and utility costs.

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.

BPS, energy efficiency and renewable energy sources for buildings greening and zero energy cities planning harmony and ethics of sustainability

Energy Technology Data Exchange (ETDEWEB)

Todorovic, Marija S. [University of Belgrade, Serbia and Southeast University (China)

2011-07-01

Traditional village houses now use renewable materials and energy sources and this paper presents the intrinsic harmony of these buildings' greening and their sustainability. The paper covers building technical systems, sustainable energy supply, and the importance of renewable raw materials (RMS) for sustainable development. This study investigated the role of building dynamic behavior and optimized energy efficiency in reducing thermal loads significantly. A preliminary design for sustainable energy efficient settlements with net zero energy buildings is proposed and a comprehensive multidisciplinary engineering study was done which identified the technical feasibility of sustainable village energy and water supplies using solar or wind technologies. Overall, through analysis of sustainability definitions and possible ways to achieve sustainability, the study demonstrated that this can only be brought about by interdisciplinary interaction and finding the right balance between materiality and spirituality, science and art, and between technological development and concern for cultural and other human values.

Experimental Evaluation of Simple Thermal Storage Control Strategies in Low-Energy Solar Houses to Reduce Electricity Consumption during Grid On-Peak Periods

Directory of Open Access Journals (Sweden)

Kyoung-Ho Lee

2015-08-01

Full Text Available There is growing interest in zero-energy and low-energy buildings, which have a net energy consumption (on an annual basis of almost zero. Because they can generate both electricity and thermal energy through the use of solar photovoltaic (PV and solar thermal collectors, and with the help of reduced building thermal demand, low-energy buildings can not only make a significant contribution to energy conservation on an annual basis, but also reduce energy consumption and peak demand. This study focused on electricity consumption during the on-peak period in a low-energy residential solar building and considers the use of a building’s thermal mass and thermal storage to reduce electricity consumption in summer and winter by modulation of temperature setpoints for heat pump and indoor thermostats in summer and additional use of a solar heating loop in winter. Experiments were performed at a low-energy solar demonstration house that has solar collectors, hot water storage, a ground-coupled heat pump, and a thermal storage tank. It was assumed that the on-peak periods were from 2 pm to 5 pm on hot summer days and from 5 pm to 8 pm on cold winter days. To evaluate the potential for utilizing the building’s thermal storage capacity in space cooling and heating, the use of simple control strategies on three test days in summer and two test days in the early spring were compared in terms of net electricity consumption and peak demand, which also considered the electricity generation from solar PV modules on the roof of the house.

Solar 2 Green Energy, Arts & Education Center. Final Scientific/Technical Report

Energy Technology Data Exchange (ETDEWEB)

Paquette, Jamie C; Collins, Christopher J

2011-07-18

The Solar 2 Green Energy, Arts and Education Center is an 8,000 sq.ft. demonstration project that will be constructed to Platinum LEED certification and will be the first carbon-neutral, net-zero energy use public building in New York City, giving it local and national appeal. Employing green building features and holistic engineering practices throughout its international award-winning design, Solar 2 will be powered by a 90kW photovoltaic (PV) array in conjunction with a geothermal heating and cooling system and a high efficient design that seeks to reduce the overall energy load of the building. Solar 2 will replace our current 500 sq.ft. prototype facility - known as Solar 1 - as the educational and cultural centerpiece of a five-block public greenway on the East River in Stuyvesant Cove Park, located along two acres of public riverfront on a newly reclaimed, former brownfield in lower Manhattan. Designed as a public-use complex for year-round environmental education exhibits and onsite activities for all ages and backgrounds, Solar 2 will demonstrate energy-efficiency technologies and sustainable environmental practices available now to all urban residents, eco-tourists, teachers, and students alike. Showcasing one of Solar 2's most striking design elements is the PV roof array with a cafe and river vistas for miles of New York City's skylines. Capping the building as a solar-powered landmark, and visible from the FDR Drive, the PV array is also designed to provide visitors below a view of the solar roof when standing outside, as well as directly underneath it. Recognized by an international jury of architects, civil engineers and urban designers by the Swiss-based Holcim Foundation, the Solar 2 design was awarded the prestigious Holcim North American 2008 Gold Award for Sustainable Construction for innovative, future-oriented and tangible sustainable construction projects, selected from more than 1900 entries. Funding from the Department of Energy

Data Sources for NetZero Ft Carson Model

Data.gov (United States)

U.S. Environmental Protection Agency — Table of values used to parameterize and evaluate the Ft Carson NetZero integrated Model with published reference sources for each value. This dataset is associated...

Experimental study on comprehensive utilization of solar energy and energy balance in an integrated solar house

International Nuclear Information System (INIS)

Chang, Huawei; Liu, Yuting; Shen, Jinqiu; Xiang, Can; He, Sinian; Wan, Zhongmin; Jiang, Meng; Duan, Chen; Shu, Shuiming

2015-01-01

Highlights: • Active and passive solar house technology is integrated in the solar house. • Solar thermal system and solar photoelectric system are measured and analyzed. • Energy balance and energy consumption are analyzed with valuable experimental data. • “Zero energy consumption” is truly achieved with the solar supply rate of 1.19 in winter. - Abstract: An integrated solar house with numerous advanced envelops is designed and constructed to investigate the comprehensive utilization of solar energy, energy efficiency and energy balance, which combines active solar house technology with passive solar house technology including solar photovoltaic system, solar water heating system, direct-gain door and windows. Solar radiation intensity, performance of the photovoltaic system, water temperature, and indoor and outdoor temperature are measured, results of the experiments indicate that solar glass window on the south wall can maintain the average indoor temperature at 21.4 °C in the case of average outdoor temperature at 11.2 °C without any external heat supply. The output current of the solar photovoltaic system shows the same trend as solar radiation intensity. When the intensity is 619.7 W/m"2, the instantaneous generation power could reach a value of 781.9 W, cumulative capacity throughout the day achieves 4.56 kW h and photovoltaic conversion efficiency 9.8%. When the average intensity throughout a day is 358 W/m"2, the solar water heating system could help to raise the temperature of 450 L water by 30 °C with its heat collecting efficiency being 37.4%. Through the analysis of the overall energy system in the solar house, it can be derived that this solar house could achieve “zero energy consumption” in winter with the solar supply rate at 1.19.

DOE Zero Energy Ready Home Case Study: Amaris Custom Homes, St.Paul, Minnesota; DOE Zero Energy Ready Home Case Study, Energy Efficiency & Renewable Energy (EERE)

Energy Technology Data Exchange (ETDEWEB)

2015-06-01

For this project Amaris worked with U.S. Department of Energy (DOE) team, NorthernSTAR Building America Partnership, to approach zero energy in Minnesota's cold climate using reasonable, cost-effective, and replicable construction materials and practices. The result is a passive solar, super-efficient 3542-ft2 walkout rambler with all the creature comforts.

Proceedings of the Canadian Solar Buildings Conference : the 31. annual conference of the Solar Energy Society of Canada Inc. and the 1. Canadian Solar Buildings Research Network conference

International Nuclear Information System (INIS)

Athienitis, A.; Charron, R.; Karava, P.; Stylianou, M.; Tzempelikos, A.

2006-01-01

The first conference organized by the newly established Canadian Solar Buildings Research Network (SBRN) was held in conjunction with the thirty-first annual conference of the Solar Energy Society of Canada Inc (SESCI). The conference was attended by top researchers from 10 Canadian Universities to promote innovative research and development in solar energy applications and to advance the awareness of solar energy in Canada. It featured special events such as trade shows, photovoltaic workshops, a course in ESP-r simulation, tours of solar houses and other events focused on the economic, environmental and socio-economic benefits of solar technology, including the potential to reduce greenhouse gas emissions. SBRN was founded on the premise that university researchers should focus on solar energy applications for buildings. Several presentations proposed action plans to accelerate the implementation of solar energy through the use of innovative building technologies and sustainable energy policies. Other major issues of interest were also discussed, including the development of the net-zero energy solar home and grid-connection issues. The sessions of the conference were entitled: solar thermal systems; solar electricity; building integrated photovoltaic systems; design issues and tools; integrating PV and solar thermal in buildings; daylighting and solar radiation modeling; fenestration and shading; PV manufacturing and solar electricity resources. The proceedings featured 41 refereed papers and 13 poster presentations, all of which have been catalogued separately for inclusion in this database. refs., tabs., figs

"Watts per person" paradigm to design net zero energy buildings: Examining technology interventions and integrating occupant feedback to reduce plug loads in a commercial building

Science.gov (United States)

Yagi Kim, Mika

As building envelopes have improved due to more restrictive energy codes, internal loads have increased largely due to the proliferation of computers, electronics, appliances, imaging and audio visual equipment that continues to grow in commercial buildings. As the dependency on the internet for information and data transfer increases, the electricity demand will pose a challenge to design and operate Net Zero Energy Buildings (NZEBs). Plug Loads (PLs) as a proportion of the building load has become the largest non-regulated building energy load and represents the third highest electricity end-use in California's commercial office buildings, accounting for 23% of the total building electricity consumption (Ecova 2011,2). In the Annual Energy Outlook 2008 (AEO2008), prepared by the Energy Information Administration (EIA) that presents long-term projections of energy supply and demand through 2030 states that office equipment and personal computers are the "fastest growing electrical end uses" in the commercial sector. This thesis entitled "Watts Per Person" Paradigm to Design Net Zero Energy Buildings, measures the implementation of advanced controls and behavioral interventions to study the reduction of PL energy use in the commercial sector. By integrating real world data extracted from an energy efficient commercial building of its energy use, the results produce a new methodology on estimating PL energy use by calculating based on "Watts Per Person" and analyzes computational simulation methods to design NZEBs.

The Economics of Zero-Rating and Net Neutrality

OpenAIRE

Somogyi, Robert

2016-01-01

This paper studies zero-rating, an emerging business practice consisting in a mobile internet service provider (ISP) excluding the data generated by certain content providers (CPs) from its consumers' monthly data cap. Being at odds with the principle of net neutrality, these arrangements have recently attracted regulatory scrutiny all over the word. I analyze zero-rating incentives of a monopolistic ISP facing a capacity constraint in a two-sided market where consumption provides utility for...

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.

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...

Net metering: zero electricity bill

International Nuclear Information System (INIS)

Mangi, A.; Khan, Z.

2011-01-01

Worldwide move towards renewable energy sources, environmental concerns and decentralization of the power sector have made net metering an attractive option for power generation at small scale. This paper discusses the net metering, economical issues of renewable sources in Pakistan, technical aspects, installation suitability according to varying terrain, existing utility rules and formulation of legislation for net metering making it economically attractive. (author)

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.

Energy dashboard for real-time evaluation of a heat pump assisted solar thermal system

Science.gov (United States)

Lotz, David Allen

The emergence of net-zero energy buildings, buildings that generate at least as much energy as they consume, has lead to greater use of renewable energy sources such as solar thermal energy. One example is a heat pump assisted solar thermal system, which uses solar thermal collectors with an electrical heat pump backup to supply space heating and domestic hot water. The complexity of such a system can be somewhat problematic for monitoring and maintaining a high level of performance. Therefore, an energy dashboard was developed to provide comprehensive and user friendly performance metrics for a solar heat pump system. Once developed, the energy dashboard was tested over a two-week period in order to determine the functionality of the dashboard program as well as the performance of the heating system itself. The results showed the importance of a user friendly display and how each metric could be used to better maintain and evaluate an energy system. In particular, Energy Factor (EF), which is the ratio of output energy (collected energy) to input energy (consumed energy), was a key metric for summarizing the performance of the heating system. Furthermore, the average EF of the solar heat pump system was 2.29, indicating an efficiency significantly higher than traditional electrical heating systems.

Investigating the impact of different thermal comfort models for zero energy buildings in hot climates

NARCIS (Netherlands)

Attia, S.G.; Hensen, J.L.M.

2014-01-01

The selection of a thermal comfort model has a major impact on energy consumption of Net Zero Energy Buildings (NZEBs) in hot climates. The objective of this paper is to compare the influence of using different comfort models for zero energy buildings in hot climates. The paper compares the impact

Multi-Criteria Analysis of Alternative Energy Supply Solutions to Public Nearly Zero Energy Buildings

Directory of Open Access Journals (Sweden)

Giedrius Šiupšinskas

2013-12-01

Full Text Available The article analyzes energy supply alternatives for modernised public nearly zero energy buildings. The paper examines alternative energy production systems such as heat pumps (air-water and ground-water, solar collectors, adsorption cooling, biomass boiler, solar photovoltaic, wind turbines and combinations of these systems. The simulation of the analysed building energy demand for different energy production alternatives has been performed using TRNSYS modelling software. In order to determine an optimal energy supply variant, the estimated results of energy, environmental, and economic evaluation have been converted into non-dimensional variables (3E using multi-criteria analysis.Article in Lithuanian

Solar Systems for Heating and Cooling of Buildings

OpenAIRE

Henning, Hans-Martin; Döll, Jochen

2012-01-01

Recently, the concept of net zero energy buildings has become a major topic in the R&D work on future buildings. In order to achieve a zero energy balance on annual level energy saving and energy efficiency measures have to be fully exploited. However, a demand for active heating and/or cooling will remain in most buildings and under most climatic conditions. Solar energy is the main on-site renewable energy source which can be used to achieve a high fraction of renewable energies to cover th...

NREL/Habitat for Humanity Zero Energy Home: A Cold-Climate Case Study for Affordable Zero Energy Homes

Energy Technology Data Exchange (ETDEWEB)

Norton, P.; Christensen, C.; Hancock, E.; Barker, G.; Reeves, P.

2008-06-01

The design of this 1,280-square-foot, three-bedroom Habitat for Humanity of Metro Denver zero energy home carefully combines envelope efficiency, efficient equipment, appliances and lighting, and passive and active solar features to reach the zero energy goal. The home was designed with an early version (July 22, 2004) of the BEOpt building optimization software; DOE2 and TRNSYS were used to perform additional analysis. This engineering approach was tempered by regular discussions with Habitat construction staff and volunteers. These discussions weighed the applicability of the optimized solutions to the special needs and economics of a Habitat house--moving the design toward simple, easily maintained mechanical systems and volunteer-friendly construction techniques. A data acquisition system was installed in the completed home to monitor its performance.

Analysis of Photovoltaic Applications in Zero Energy Building Cases of IEA SHC/EBC Task 40/Annex 52

Directory of Open Access Journals (Sweden)

Jin-Hee Kim

2015-07-01

Full Text Available A Net Zero Energy Building (NZEB considerably reduces the building energy load through high efficiency equipment and passive elements such as building orientation, high insulation, natural daylighting, and ventilation in order to achieve zero energy balance with on-site energy production from renewable energy systems applied to the building. For a Zero Energy Building (ZEB, the heating energy demand can be significantly reduced with high insulation and air tightness, while the cooling energy demand can be curtailed by applying shading device, cross ventilation, etc. As such, the electrical energy demand for a ZEB is relatively higher than its heat energy demand. Therefore, the application of a Renewable Energy System (RES to produce electricity is necessary for a ZEB. In particular, Building Integrated Photovoltaic (BIPV systems that generate electricity can play an important role for achieving zero energy balance in buildings; BIPVs are multi-functional and there are many ways to apply them into buildings. This study comprehensively analyzes photovoltaic (PV applications in ZEB cases through the International Energy Agency Solar Heating and Cooling Programme (IEA SHC/Energy in Buildings and Communities Programme (EBC Task 40/Annex 52 activities, which include PV installation methods, PV cell type, and electricity generation. The most widely applied RES is the PV system, corresponding to 29 out of a total of 30 cases. Among the roof type PV systems, 71% were non-integrated. In addition, 14 of the 27 cases in which PV systems were applied, satisfied over 100% of the electricity energy demand from the PV system and were found to generate surplus electrical power.

The solar greenhouse: a survey of energy saving methods

NARCIS (Netherlands)

Saye, A.; Loon, van W.K.P.; Bot, G.P.A.; Zwart, de H.F.

2000-01-01

The solar greenhouse project is aimed at the development of a greenhouse concept for the Netherlands with zero-fossil energy consumption. The solar greenhouse is formulated as a combination of a low energy demand greenhouse, an energy recovery installation and an energy storage facility. In this

Comparison of the energy and environmental impact by integrating a H_2 vehicle and an electric vehicle into a zero-energy building

International Nuclear Information System (INIS)

Cao, Sunliang

2016-01-01

Highlights: • Integrating a commercial-scale H_2 vehicle (HV) or electric vehicle (EV) into a ZEB. • Simultaneously fulfilling net-zero energy building and absolute-zero energy vehicle. • Energy performance comparison between the ZEBs with HV, EV, and no vehicle. • The energy matching-enhancing solutions for integrating the HV or EV with the ZEB. • Solutions for improving the matching and relieving the negative impact on the grid. - Abstract: The boundary extension of a zero-energy building to integrate a new energy vehicle will facilitate the realization of the target set by the EU 2050 roadmap. In this study, either a hydrogen vehicle (HV) or an electric vehicle (EV) is integrated into a renewable-supported building system with appropriate control strategies. The focused variables in this study are renewable energy capacities, vehicle system options, extents to utilize vehicle storages for domestic purposes, and the Excess REe-HW recharging strategies. The analysing aspects include the energy and environmental impact as well as the energy matching and the grid interactions. The results show that the annual net-zero energy/emission balance can be met by a 16, 12, and 12 kW rated wind turbine, or by a 195.8, 160.2, and 142.4 m"2 PV, for the building with the HV, the EV and no vehicle (NV), respectively. The building with the HV will be more demanding in meeting the balance due to the less efficient HV system than that with the EV. Moreover, better matching for the zero-energy system can be achieved by relieving the condition to discharge the vehicle storages for domestic usages and by using the Excess REe-HW recharging strategy. However, their negative effect will be a slight increase in the annual net-energy consumption, due to an increased loss from both the HV/EV integrated system and the thermal storage.

On the Path to Zero Energy Homes

Energy Technology Data Exchange (ETDEWEB)

Merrigan, T.

2001-03-30

Just imagine living in Florida and your fantasies might turn to swaying palms, fresh orange juice and lots of air-conditioning. For most people, a summer spent in Florida's heat and humidity would be unbearable without it. So air-conditioning is a necessity. But it's also a big energy drain, accounting for about 35% of all electricity used in a typical Florida house. As the largest single source of energy consumption in Florida, a home's air-conditioning load represents the biggest energy challenge. The Florida Solar Energy Center (FSEC) designed a project to answer this challenge. Two homes were built with the same floor plan on near-by lots. The difference was that one (the ''control home'') conformed to local residential building practices, and the other (the ''Zero Energy home'') was designed with energy efficiency in mind and solar technology systems on the roof. The homes were then monitored carefully for energy use. The project's designers were looking to answer two important questions: Could a home in a climate such as central Florida's be engineered and built so efficiently that a relatively small PV system would serve the majority of its cooling needs--and even some of its daytime electrical needs? And, would that home be as comfortable and appealing as the conventional model built alongside it? The answer to both questions turned out to be a resounding yes. And the test was especially rigorous, because it was conducted in the summer of 1998--one of the hottest summers on record in Florida. This news is important for city planners, architects, builders, and homeowners not only in the Sunshine State, but elsewhere, too. The solar/energy efficiency combo worked so well in Florida that it can--and should--be tried in other parts of the country. This brochure describes the Zero Energy Homes concept using a case study.

Progressing Deployment of Solar Photovoltaic Installations in the United States

Science.gov (United States)

Kwan, Calvin Lee

2011-07-01

This dissertation evaluates the likelihood of solar PV playing a larger role in national and state level renewable energy portfolios. I examine the feasibility of large-scale solar PV arrays on college campuses, the financials associated with large-scale solar PV arrays and finally, the influence of environmental, economic, social and political variables on the distribution of residential solar PV arrays in the United States. Chapter two investigates the challenges and feasibility of college campuses adopting a net-zero energy policy. Using energy consumption data, local solar insolation data and projected campus growth, I present a method to identify the minimum sized solar PV array that is required for the City College campus of the Los Angeles Community College District to achieve net-zero energy status. I document how current energy demand can be reduced using strategic demand side management, with remaining energy demand being met using a solar PV array. Chapter three focuses on the financial feasibility of large-scale solar PV arrays, using the proposed City College campus array as an example. I document that even after demand side energy management initiatives and financial incentives, large-scale solar PV arrays continue to have ROIs greater than 25 years. I find that traditional financial evaluation methods are not suitable for environmental projects such as solar PV installations as externalities are not taken into account and therefore calls for development of alternative financial valuation methods. Chapter four investigates the influence of environmental, social, economic and political variables on the distribution of residential solar PV arrays across the United States using ZIP code level data from the 2000 US Census. Using data from the National Renewable Energy Laboratory's Open PV project, I document where residential solar PVs are currently located. A zero-inflated negative binomial model was run to evaluate the influence of selected variables

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.

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.

Achieving Very High Efficiency and Net Zero Energy in an Existing Home in a Hot-Humid Climate. Long-Term Utility and Monitoring Data

Energy Technology Data Exchange (ETDEWEB)

Parker, D. [BA-PIRC/ Florida Solar Energy Center, Cocoa, FL (United States); Sherwin, J. [BA-PIRC/ Florida Solar Energy Center, Cocoa, FL (United States)

2012-10-01

This study summarizes the first six months of detailed data collected on a single family home that experienced a series of retrofits targeting reductions in energy use. The project was designed to develop data on how envelope modifications and renewable measures can result in considerable energy reductions and potentially net zero energy for an existing home. Originally published in February 2012, this revised version of the report contains further research conducted on the Parker residence. Key updates include one full year of additional data, an analysis of cooling performance of the mini-split heat pump, an evaluation of room-to-room temperature distribution, and an evaluation of plug-in automobile charging performance, electricity consumption, and load shape.

Place-Based Learning: Interactive Learning and Net-Zero Design

Science.gov (United States)

Holser, Alec; Becker, Michael

2011-01-01

Food and conservation science curriculum, net-zero design and student-based building performance monitoring have come together in the unique and innovative new Music and Science Building for Oregon's Hood River Middle School. The school's Permaculture-based curriculum both informed the building design and was also transformed through the…

Sacramento State Solar Decathlon 2015: Research Performance Final Report

Energy Technology Data Exchange (ETDEWEB)

Anderson, Mikael [California State Univ., Sacramento, CA (United States). Dept. of Construction Management

2017-03-14

Our primary objective is to design and build a 600-1000sf home that produces more energy than it consumes and to showcase this home at the 2015 Solar Decathlon in Irvine, CA. Further objectives are to educate consumers and home builders, alike (including K-12 students – the industry’s future consumers), inspire a shift towards the adoption of net-zero energy solutions in residential building, and to be a leader in the transformation of the California residential marketplace to a net-zero standard. Our specific mission statement for this project is as follows: Solar NEST strives to discover the future of sustainable, energy-efficient housing and deliver these innovations to home buyers at an affordable price. To make substantial improvements to conventional building methods with regard to aesthetics, performance, and affordability. Through our efforts, we aspire to bridge the gap between ‘what is’ and ‘what is possible’ by providing unique, elegant simplicity.

Life Cycle Cost optimization of a BOLIG+ Zero Energy Building

Energy Technology Data Exchange (ETDEWEB)

Marszal, A.J.

2011-12-15

Buildings consume approximately 40% of the world's primary energy use. Considering the total energy consumption throughout the whole life cycle of a building, the energy performance and supply is an important issue in the context of climate change, scarcity of energy resources and reduction of global energy consumption. An energy consuming as well as producing building, labelled as the Zero Energy Building (ZEB) concept, is seen as one of the solutions that could change the picture of energy consumption in the building sector, and thus contribute to the reduction of the global energy use. However, before being fully implemented in the national building codes and international standards, the ZEB concept requires a clear understanding and a uniform definition. The ZEB concept is an energy-conservation solution, whose successful adaptation in real life depends significantly on private building owners' approach to it. For this particular target group, the cost is often an obstacle when investing money in environmental or climate friendly products. Therefore, this PhD project took the perspective of a future private ZEB owner to investigate the cost-optimal Net ZEB definition applicable in the Danish context. The review of the various ZEB approaches indicated a general concept of a Zero Energy Building as a building with significantly reduced energy demand that is balanced by an equivalent energy generation from renewable sources. And, with this as a general framework, each ZEB definition should further specify: (1) the connection or the lack of it to the energy infrastructure, (2) the unit of the balance, (3) the period of the balance, (4) the types of energy use included in the balance, (5) the minimum energy performance requirements (6) the renewable energy supply options, and if applicable (7) the requirements of the building-grid interaction. Moreover, the study revealed that the future ZEB definitions applied in Denmark should mostly be focused on grid

Achieving Very High Efficiency and Net Zero Energy in an Existing Home in a Hot-Humid Climate: Long-Term Utility and Monitoring Data (Revised)

Energy Technology Data Exchange (ETDEWEB)

Parker, D.; Sherwin, J.

2012-10-01

This study summarizes the first six months of detailed data collected on a single family home that experienced a series of retrofits targeting reductions in energy use. The project was designed to develop data on how envelope modifications and renewable measures can result in considerable energy reductions and potentially net zero energy for an existing home. Originally published in February 2012, this revised version of the report contains further research conducted on the Parker residence. Key updates include one full year of additional data, an analysis of cooling performance of the mini-split heat pump, an evaluation of room-to-room temperature distribution, and an evaluation of plug-in automobile charging performance, electricity consumption, and load shape.

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...

Energy sustainable cities. From eco villages, eco districts towards zero carbon cities

Science.gov (United States)

Zaręba, Anna; Krzemińska, Alicja; Łach, Janusz

2017-11-01

Minimizing energy consumption is the effect of sustainable design technics as among many others: designing buildings with solar access and natural ventilation, using climate responsive design materials and effective insulation. Contemporary examples of zero-carbon cities: Masdar City, United Arab Emirates and Dongtan, China, confirm technical feasibility of renewable energy by implementation of solar PV and wind technologies. The ecological city - medium or high density urban settlement separated by greenspace causes the smallest possible ecological footprint on the surrounding countryside through efficient use of land and its resources, recycling used materials and converting waste to energy. This paper investigates the concept of energy sustainable cities, examines, how urban settlements might affect building energy design in eco-villages, eco-districts (e.g. Vauban, Freiburg in Germany, Bo01 Malmo in Sweden), and discuss the strategies for achieving Zero Emission Cities principles in densely populated areas. It is focused on low energy architectural design solutions which could be incorporated into urban settlements to create ecological villages, districts and cities, designed with consideration of environmental impact, required minimal inputs of energy, water, food, waste and pollution.

SOLHYCO Project: cogeneration system with concentrated solar energy and biofuels; Projeto SOLHYCO: sistema de cogeracao de energia solar concentrada e biocombustiveis

Energy Technology Data Exchange (ETDEWEB)

Oliveira, Celso Eduardo Lins de; Rabi, Jose Antonio; Carrer, Celso da Costa; Cavinatto, Betina; Tomasella, Peterson Ricardo [Universidade de Sao Paulo (FZEA-USP), SP (Brazil). Fac. de Zootecnia e Engenharia de Alimentos

2008-07-01

Dispatchable renewable power generation is usually associated with expensive storages or additional back-up systems. Solar-hybrid systems can combine solar energy with an additional fuel and thus reliably provide electric power. If renewable fuels (e.g., biofuels) are employed, power generation becomes 100% sustainable at zero net emissions. Systems based on gas turbines are suited for cogeneration or combined cycles, making them very efficient and cost effective. These cycles require high temperatures and pressures, thus the solar energy has to be concentrated by a heliostat field onto the top of a tower and transferred by a solar receiver into the gas turbine cycle. At smaller power levels, cogeneration of heat and power is an attractive option by making use of the high exhaust temperature of the gas turbine, thus getting an additional benefit. The aim of this proposal is an significant extension of the objectives of the recently started SOLHYCO project by means A profound knowledge for market introduction will be gained by the assessment of the Brazilian market concerning solar resources, biofuels, electricity markets, heat markets and social needs. A detailed design study for a first demonstration unit will deliver all necessary economical, social and environmental data and accordingly 3 case studies have been defined. (author)

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.

Building America Case Study: New Town Builders' Power of Zero Energy Center, Denver, Colorado (Brochure)

Energy Technology Data Exchange (ETDEWEB)

2014-10-01

New Town Builders, a builder of energy efficient homes in Denver, Colorado, offers a zero energy option for all the homes it builds. To attract a wide range of potential homebuyers to its energy efficient homes, New Town Builders created a 'Power of Zero Energy Center' linked to its model home in the Stapleton community of Denver. This case study presents New Town Builders' marketing approach, which is targeted to appeal to homebuyers' emotions rather than overwhelming homebuyers with scientific details about the technology. The exhibits in the Power of Zero Energy Center focus on reduced energy expenses for the homeowner, improved occupant comfort, the reputation of the builder, and the lack of sacrificing the homebuyers' desired design features to achieve zero net energy in the home. The case study also contains customer and realtor testimonials related to the effectiveness of the Center in influencing homebuyers to purchase a zero energy home.

Here comes the sun. Solar energy technology in the USA

International Nuclear Information System (INIS)

Van der Wees, G.

1998-01-01

An overview is given of the energy policy in the USA with respect to solar energy technology and the marketing of solar energy applications. In particular, attention is paid to the Million Solar Roofs programme, small-scale and medium-scale photovoltaic (PV) systems (Residential PV and Utility Scale PV), solar thermal systems (Parabolic Trough, Power tower, and Solar Dish/Engine). Also examples of passive solar systems are given. Finally, a number of aspects with regard to market implementation, e.g. net-metering. 9 refs

Zero energy Tunnel-concept

NARCIS (Netherlands)

Dzhusupova, R.

2012-01-01

Creating a zero energy environment is a hot topic. The developments in this field are based on the concept of the "Trias Energetica": reducing energy consumption, using renewable energy sources, and efficiently using fossil fuels. A zero energy concept can also be applied to road tunnels to improve

The solar energy in Colombia, Atlas of solar radiation of Colombia

International Nuclear Information System (INIS)

Rodriguez P, F.

1995-01-01

This study was made by means of the Agreement inter-institutional subscribed between Mines Ministry and Energy, HIMAT and INEA and was published by CARBOCOL. In the evaluation of solar energy potential, the information of the radiometric net of the HIMAT taken in 203 stations distributed throughout all Country from 1980 until 1990, it was had in account. A meteorological station is an observation point where are located different instruments and equipment that serve to measure and study meteorological parameter as solar radiation (radiometer actinograph), Solar sheen (Campbell Stoke), Temperature (Thermograph), Moisture (hydrographer), Wind (Anemograph Anemometer) and Precipitation (Pluviograph)

New Whole-House Solutions Case Study: New Town Builders' Power of Zero Energy Center - Denver, Colorado

Energy Technology Data Exchange (ETDEWEB)

None

2014-10-01

New Town Builders, a builder of energy efficient homes in Denver, Colorado, offers a zero energy option for all the homes it builds. To attract a wide range of potential homebuyers to its energy efficient homes, New Town Builders created a "Power of Zero Energy Center" linked to its model home in the Stapleton community. This case study presents New Town Builders' marketing approach, which is targeted to appeal to homebuyers' emotions rather than overwhelming homebuyers with scientific details about the technology. The exhibits in the Power of Zero Energy Center focus on reduced energy expenses for the homeowner, improved occupant comfort, the reputation of the builder, and the lack of sacrificing the homebuyers' desired design features to achieve zero net energy in the home. This case study also contains customer and realtor testimonials related to the effectiveness of the Center in influencing homebuyers to purchase a zero energy home.

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

ZEMCH toward the delivery of zero energy mass custom homes

CERN Document Server

2016-01-01

In this book, leading international experts explore the emerging concept of the zero energy mass custom home (ZEMCH) – designed to meet the need for social, economic, and environmental sustainability – and provide all of the knowledge required for the delivery of zero energy mass customized housing and community developments in developed and developing countries. The coverage is wide ranging, progressing from explanation of the meaning of sustainable development to discussion of challenges and trends in mass housing, the advantages and disadvantages of prefabricated methods of construction, and the concepts of mass customization, mass personalization, and inclusive design. A chapter on energy use will aid the reader in designing and retrofitting housing to reduce energy demand and/or improve energy end‐use efficiency. Passive design strategies and active technologies (especially solar) are thoroughly reviewed. Application of the ZEMCH construction criteria to new buildings and refurbishment of old house...

Energy Toolbox—Framework for the Development of a Tool for the Primary Design of Zero Emission Buildings in European and Asian Cities

Directory of Open Access Journals (Sweden)

Christoph Koller

2017-12-01

Full Text Available This paper discusses the framework for the development of an Energy Toolbox (ETB. The aim of the ETB is to support the design of domestic Zero Emission Buildings (ZEBs, according to the concept of net zero-energy buildings during the early architectural design and planning phases. The ETB concept is based on the calculation of the energy demand for heating, cooling, lighting, and appliances. Based on a building’s energy demand, technologies for the onsite conversion and production of the specific forms and quantities of final and primary energy by means of renewable energy carriers can be identified. The calculations of the ETB are based on the building envelope properties of a primary building design, as well as the physical and climate parameters required for the calculation of heat transfer coefficients, heat gains, and heat losses. The ETB enables the selection and rough dimensioning of technologies and systems to meet, and, wherever possible, reduce the thermal and electric energy demand of a building. The technologies included comprise green facades, adaptable dynamic lighting, shading devices, heat pumps, photovoltaic generators, solar thermal collectors, adiabatic cooling, and thermal storage. The ETB facilitates the balancing of the energy consumption and the production of renewable energies of a primary building design.

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.

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

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.

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.

Experimental analysis of a direct expansion solar assisted heat pump with integral storage tank for domestic water heating under zero solar radiation conditions

International Nuclear Information System (INIS)

Fernández-Seara, José; Piñeiro, Carolina; Alberto Dopazo, J.; Fernandes, F.; Sousa, Paulo X.B.

2012-01-01

Highlights: ► We analyze a direct expansion solar assisted heat pump under zero solar radiation. ► We determine the COP and equivalent seasonal performance factors (SPFe). ► We determine the main components’ performance under transient operating conditions. ► The Huang and Lee performance evaluation method provides a characteristic COP of 3.23. - Abstract: This paper deals with the experimental evaluation of the performance of a direct expansion solar assisted heat pump water heating (DX-SAHPWH) system working under zero solar radiation conditions at static heating operation mode of the storage tank. The DX-SAHPWH system includes two bare solar collectors as evaporator, a R134a rotary-type hermetic compressor, a thermostatic expansion valve and a helical coil condenser immersed in a 300 L water storage tank. The zero solar radiation and stable ambient air temperature working conditions were established by placing the solar collectors into a climate chamber. The analysis is based on experimental data taken from the DX-SAHPWH provided by the manufacturer and equipped with an appropriate data acquisition system. In the paper, the experimental facility, the data acquisition system and the experimental methodology are described. Performance parameters to evaluate the energy efficiency, such as COP and equivalent seasonal performance factors (SPFe) for the heating period, and the water thermal stratification in the storage tank are defined and obtained from the experimental data. Results from the experimental analysis under transient operating working conditions of the DX-SAHPWH system and its main components are shown and discussed. Lastly, the Huang and Lee DX-SAHPWH performance evaluation method was applied resulting in a characteristic COP of 3.23 for the DX-SAHPWH system evaluated under zero solar radiation condition.

A Green Energy Application in Energy Management Systems by an Artificial Intelligence-Based Solar Radiation Forecasting Model

Directory of Open Access Journals (Sweden)

Ping-Huan Kuo

2018-04-01

Full Text Available The photovoltaic (PV systems generate green energy from the sunlight without any pollution or noise. The PV systems are simple, convenient to install, and seldom malfunction. Unfortunately, the energy generated by PV systems depends on climatic conditions, location, and system design. The solar radiation forecasting is important to the smooth operation of PV systems. However, solar radiation detected by a pyranometer sensor is strongly nonlinear and highly unstable. The PV energy generation makes a considerable contribution to the smart grids via a large number of relatively small PV systems. In this paper, a high-precision deep convolutional neural network model (SolarNet is proposed to facilitate the solar radiation forecasting. The proposed model is verified by experiments. The experimental results demonstrate that SolarNet outperforms other benchmark models in forecasting accuracy as well as in predicting complex time series with a high degree of volatility and irregularity.

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

A tool for design decision making - zero energy residential buildings in hot humid climates

NARCIS (Netherlands)

Attia, S.G.

2012-01-01

In this thesis, the development and evaluation of a simulation-based decision aid for Net Zero Energy Buildings (NZEBs) design, ZEBO, was explored. The thesis investigates the ability to achieve informed decision making for NZEB design, in hot climate. Four main questions were posed. Firstly, how to

Tropical Zero Energy Office Building

DEFF Research Database (Denmark)

Reimann, Gregers Peter; Kristensen, Poul Erik

2006-01-01

The new headquarter for Pusat Tenaga Malaysia is designed to be a Zero Emission Office Building (ZEO). A full range of passive and active energy efficiency measures are implemented such that the building will need no more electricity than what can be produced via its own Building Integrated PV...... lighting. These measures include the use of high efficient lighting controlled according to demand, high efficiency pumps and fans, a high efficiency chiller, and use of energy efficient office equipment. The buildings PV system is connected to the grid. Solar electricity is exported to the grid during...... of 24 – 26 oC can be maintained throughout the office hours. The PV roof of the building serves multiple purposes. During daytime, the roof becomes the powerplant of the building, and during nighttime, the PV roof becomes the “cooling tower” for the chiller. The roof will be covered by a thin water film...

Demonstrate Energy Component of the Installation Master Plan Using Net Zero Installation Virtual Testbed

Science.gov (United States)

2015-09-01

compliant GIS, usually obtained from the installation itself. NZP also includes an appropriate weather file for the location selected, using the closest...such as solar photovoltaics, solar-thermal, wind energy, biomass (wood chips, etc.), biogas , or synthetic gas need to be considered as part of the mix...have better information. In some cases, such as photovoltaics, users can obtain data from an online system and enter it into NZP. In this case, users

Enhanced Solar-to-Hydrogen Generation with Broadband Epsilon-Near-Zero Nanostructured Photocatalysts

KAUST Repository

Tian, Yi

2017-05-08

The direct conversion of solar energy into fuels or feedstock is an attractive approach to address increasing demand of renewable energy sources. Photocatalytic systems relying on the direct photoexcitation of metals have been explored to this end, a strategy that exploits the decay of plasmonic resonances into hot carriers. An efficient hot carrier generation and collection requires, ideally, their generation to be enclosed within few tens of nanometers at the metal interface, but it is challenging to achieve this across the broadband solar spectrum. Here the authors demonstrate a new photocatalyst for hydrogen evolution based on metal epsilon-near-zero metamaterials. The authors have designed these to achieve broadband strong light confinement at the metal interface across the entire solar spectrum. Using electron energy loss spectroscopy, the authors prove that hot carriers are generated in a broadband fashion within 10 nm in this system. The resulting photocatalyst achieves a hydrogen production rate of 9.5 µmol h-1  cm-2 that exceeds, by a factor of 3.2, that of the best previously reported plasmonic-based photocatalysts for the dissociation of H2 with 50 h stable operation.

How the Army Meter Data Management System (MDMS) Can Help on the Path to Net Zero

Science.gov (United States)

2011-05-10

NY) • Meets DoD cyber-security requirements – Received Authority to Operate from Army NETCOM effective 23 April 2010 – Received Certificate of...How MDMS supports Net Zero Goals (cont) 4. Measure Production/Consumption balance a. Only way to demonstrate position on glide path to Net Zero 5...2010001D To 8 Aug 2010 00 00 En•l’iY f*ttk COnWtnptlon J96S9U81’ WII FillCilftl .. Totol , ......... ~ Metert - Met el\\ r;’l £1Htr1< 1....-J G.n

Energy Analysis at a Near Zero Energy Building. A Case-Study in Spain

Directory of Open Access Journals (Sweden)

Javier M. Rey-Hernández

2018-04-01

Full Text Available This paper develops an energy analysis for an existing near Zero Energy (nZEB and Zero Carbon Emissions building called LUCIA, located at the university campus in Valladolid (Spain. It is designed to supply electricity, cooling and heating needs through solar energy (Photovoltaic Systems, PV, biomass and an Earth–Air Heat Exchanger (EAHE, besides a Combined Heat Power (CHP. It is currently among the top three buildings with the highest LEED certification in the World. The building model is simulated with DesignBuilder version 5. The results of the energy analysis illustrate the heating, cooling and lighting consumptions expected, besides other demands and energy uses. From this data, we carried out an energy balance of the nZEB, which will help to plan preventive actions when compared to the actual energy consumptions, improving the management and control of both the building and its systems. The primary energy indicator obtained is 67 kWh/m2 a year, and 121 kWh/m2 a year for renewable energy generation, with respect to 55 kWh/m2 and 45 kWh/m2 set as reference in Europe. The Renewable Energy Ratio (RER is 0.66. These indicators become a useful tool for the energy analysis of the nZEB according to the requirements in the European regulations and for its comparison with further nZEB.

Zero point energy of renormalized Wilson loops

International Nuclear Information System (INIS)

Hidaka, Yoshimasa; Pisarski, Robert D.

2009-01-01

The quark-antiquark potential, and its associated zero point energy, can be extracted from lattice measurements of the Wilson loop. We discuss a unique prescription to renormalize the Wilson loop, for which the perturbative contribution to the zero point energy vanishes identically. A zero point energy can arise nonperturbatively, which we illustrate by considering effective string models. The nonperturbative contribution to the zero point energy vanishes in the Nambu model, but is nonzero when terms for extrinsic curvature are included. At one loop order, the nonperturbative contribution to the zero point energy is negative, regardless of the sign of the extrinsic curvature term.

Incentives for solar energy in industry

Science.gov (United States)

Bergeron, K. D.

1981-05-01

Several issues are analyzed on the effects that government subsidies and other incentives have on the use of solar energy in industry, as well as on other capital-intensive alternative energy supplies. Discounted cash flow analysis is used to compare tax deductions for fuel expenses with tax credits for capital investments for energy. The result is a simple expression for tax equity. The effects that market penetration of solar energy has on conventional energy prices are analyzed with a free market model. It is shown that net costs of a subsidy program to the society can be significantly reduced by price. Several government loan guarantee concepts are evaluated as incentives that may not require direct outlays of government funds; their relative effectiveness in achieving loan leverage through project financing, and their cost and practicality, are discussed.

Roadmap for improving roof and façade windows in nearly zero-energy houses in Europe

DEFF Research Database (Denmark)

Skarning, Gunnlaug Cecilie Jensen; Hviid, Christian Anker; Svendsen, Svend

2016-01-01

Windows are central for the development of liveable nearly zero-energy homes and require careful consideration. Various studies have indicated that the effect of windows on energy consumption may change significantly with improved building insulation levels. Current guidelines on windows may...... comfort in nearly zero-energy houses located in the European cities Rome and Copenhagen. The aim was to identify options that can support the easy and robust design of future homes with typical use of roof and façade windows. Hourly daylight levels were calculated in DAYSIM, while space heating demand...... and operative temperatures were calculated in EnergyPlus. The results support previous findings on the limited ability of nearly zero-energy buildings to utilise solar gains. It was found that U-values are becoming increasingly important for the energy performance of windows. The paper sketches the increased...

Idaho | Midmarket Solar Policies in the United States | Solar Research |

Science.gov (United States)

% interest for solar PV projects. Low-interest financing Idaho Energy Resources Authority Solar PV project for financing through the Idaho Governor's Office and the Idaho Energy Resources Authority. Latest -owned community solar project for Idaho Power. Net Metering Idaho does not have statewide net metering

Zero Point Energy of Renormalized Wilson Loops

OpenAIRE

Hidaka, Yoshimasa; Pisarski, Robert D.

2009-01-01

The quark antiquark potential, and its associated zero point energy, can be extracted from lattice measurements of the Wilson loop. We discuss a unique prescription to renormalize the Wilson loop, for which the perturbative contribution to the zero point energy vanishes identically. A zero point energy can arise nonperturbatively, which we illustrate by considering effective string models. The nonperturbative contribution to the zero point energy vanishes in the Nambu model, but is nonzero wh...

Prediction of transverse asymmetries in MHD ducts with zero net Hall current

International Nuclear Information System (INIS)

Swean, T.F. Jr.; Oliver, D.A.; Maxwell, C.D.; Demetriades, S.T.

1981-01-01

A new class of fluid-electrical asymmetries in MHD generator channel flow are predicted. It is shown that the existence of interelectrode asymmetries is not confined to generators in which there exists a nonzero net axial current, but rather they are induced even in the case of the Faraday generators. Also demonstrated is the impact of these asymmetries upon the generator and diffuser flow. It is concluded that in MHD generators, the net axial current in the cross plane is identically zero, while at any given point in the plane, the local Hall current density is in general nonzero

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

NexusHaus: Solar Decathlon House

Energy Technology Data Exchange (ETDEWEB)

Garrison, Michael Lynn [University of Texas at Austin

2017-04-04

The University of Texas at Austin and The Technical University of Munich 2015 Solar Decathlon house is called Nexushaus because it combines UT Austin and TUM students in an affordable modular residential green building in the context of Austin, Texas, based on shape forming principles found in nature that demonstrates transformative technologies in Zero Net Energy, Zero Net Water and Carbon Neutrality. To meet the needs of the competition, a portable modular design has been developed with an assembly that enables ease of installation and both quantitative and qualitative performance in the design. The prefabricated house sits lightly on the land and forms the superstructure for photovoltaic technologies, rainwater collection, aquaculture and permaculture gardening and indoor/outdoor living. The ultimate goal of Nexushaus is to serve as a potential prototype for a next-generation modular home that could be reproduced in mass in an assembly plant in Austin.

Life Cycle Cost Optimization of a Bolig+ Zero Energy Building

DEFF Research Database (Denmark)

Marszal, Anna Joanna

. However, before being fully implemented in the national building codesand international standards, the ZEB concept requires a clear understanding and a uniform definition. The ZEB concept is an energy-conservation solution, whose successful adaptation in real life depends significantly on private building...... owners’ approach to it. For thisparticular target group, the cost is often an obstacle when investing money in environmental or climate friendly products. Therefore, this PhD project took theperspective of a future private ZEB owner to investigate the cost-optimal Net ZEB definition applicable...... in the Danish context. The review of the various ZEB approaches indicated a general concept of a Zero Energy Building as a building with significantly reduced energy demand that isbalanced by an equivalent energy generation from renewable sources. And, with this as a general framework, each ZEB definition...

Energy balance in solar and stellar chromospheres

Science.gov (United States)

Avrett, E. H.

1981-01-01

Net radiative cooling rates for quiet and active regions of the solar chromosphere and for two stellar chromospheres are calculated from corresponding atmospheric models. Models of chromospheric temperature and microvelocity distributions are derived from observed spectra of a dark point within a cell, the average sun and a very bright network element on the quiet sun, a solar plage and flare, and the stars Alpha Boo and Lambda And. Net radiative cooling rates due to the transitions of various atoms and ions are then calculated from the models as a function of depth. Large values of the net radiative cooling rate are found at the base of the chromosphere-corona transition region which are due primarily to Lyman alpha emission, and a temperature plateau is obtained in the transition region itself. In the chromospheric regions, the calculated cooling rate is equal to the mechanical energy input as a function of height and thus provides a direct constraint on theories of chromospheric heating.

The impact of Zero Energy Buildings on the Scandinavian energy system

International Nuclear Information System (INIS)

Seljom, Pernille; Lindberg, Karen Byskov; Tomasgard, Asgeir; Doorman, Gerard; Sartori, Igor

2017-01-01

This paper investigates how an extensive implementation of net Zero Energy Buildings (ZEBs) affects cost-optimal investments in the Scandinavian energy system towards 2050. Analyses are done by a stochastic TIMES model with an explicit representation of the short-term uncertainty related to electricity supply and heat demand in buildings. We define a nearly ZEB to be a highly efficient building with on-site PV production. To evaluate the flexibility requirement of the surrounding energy system, we consider no use of energy storage within the ZEBs. The results show that ZEBs reduce the investments in non-flexible hydropower, wind power and Combined Heat and Power, and increase the use of direct electric heating and electric boilers. With building integrated PV production of 53 TWh in 2050, ZEBs increase the Scandinavian electricity generation by 16 TWh and increase the net electricity export by 19 TWh. Although the increased production reduces the electricity prices, the low heat demand in ZEBs gives a drop in the electricity consumption by 4 TWh in 2050. Finally, the results demonstrate that the Scandinavian energy system is capable of integrating a large amount of ZEBs with intermittent PV production due to the flexible hydropower in Norway and Sweden. - Highlights: • We analyse cost-optimal integration of ZEBs in the Scandinavian energy system. • We capture impact of short-term uncertainty on long-term investment decisions. • ZEBs reduce the investments in the electricity and heating sector. • The Scandinavian electricity sector is capable of integrating ZEBs with PV. • The operation of the flexible hydropower is changed with ZEBs.

D-tagatose is a bulk sweetener with zero energy determined in rats.

Science.gov (United States)

Livesey, G; Brown, J C

1996-06-01

The ketohexose D-tagatose is readily oxidized but contributes poorly to lipid deposition. We therefore examined whether this sugar contributes to energy requirements by determining its net metabolizable energy value in rats. All substrate-induced energy losses from D-tagatose, with sucrose as reference standard, were determined as a single value accounting for the sum of the energy losses to feces, urine, gaseous hydrogen and methane and substrate-induced thermogenesis. A randomized parallel design involving two treatment periods (adaptation to D-tagatose and subsequent energy balance) and two control groups (to control for treatment effects in each period) was used. Rats consumed 1.8 g test carbohydrate daily as a supplement to a basal diet for a 40- or 41-d balance period after prior adaptation for 21 d. Growth, protein and lipid deposition were unaffected by supplementary gross energy intake from D-tagatose compared with an unsupplemented control, but sucrose significantly (P tagatose contributed -3 +/- 14% of its heat of combustion to net metabolizable energy, and therefore this ketohexose effectively has a zero energy value. D-Tagatose would potentially be helpful in body weight control, especially in diabetic subjects because of its antidiabetogenic effects.

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

Solar energy system performance evaluation. Seasonal report for Wormser, Columbia, South Carolina

Science.gov (United States)

1980-01-01

The Wormser Solar Energy System's operational performance from April 1979 through March 1980 was evaluated. The space heating subsystem met 42 percent of the measured space heating load and the hot water subsystem met 23 percent of the measured hot water demand. Net electrical energy savings were 4.36 million Btu's or 1277 kwh. Fossil energy savings will increase considerably if the uncontrolled solar energy input to the building is considered.

Impact of façade window design on energy, daylighting and thermal comfort in nearly zero-energy houses

DEFF Research Database (Denmark)

Vanhoutteghem, Lies; Skarning, Gunnlaug Cecilie Jensen; Hviid, Christian Anker

2015-01-01

a solution space defined by targets for daylighting and thermal comfort. In contrast with existing guidelines, the results show an upper limit for energy savings and utilisation of solar gains in south-oriented rooms. Instead, low U-values are needed in both north- and south oriented rooms before large......Appropriate window solutions are decisive for the design of 'nearly zero-energy' buildings with healthy and comfortable indoor environment. This paper focuses on the relationship between size, orientation and glazing properties of façade windows for different side-lit room geometries in Danish...... 'nearly zero-energy' houses. The effect of these parameters on space heating demand, daylighting and thermal environment is evaluated by means of EnergyPlus and DAYSIM and presented in charts illustrating how combinations of design parameters with minimum space heating demand can be selected within...

Solar power satellite life-cycle energy recovery consideration

Science.gov (United States)

Weingartner, S.; Blumenberg, J.

The construction, in-orbit installation and maintenance of a solar power satellite (SPS) will demand large amounts of energy. As a minimum requirement for an energy effective power satellite it is asked that this amount of energy be recovered. The energy effectiveness in this sense resulting in a positive net energy balance is a prerequisite for cost-effective power satellite. This paper concentrates on life-cycle energy recovery instead on monetary aspects. The trade-offs between various power generation systems (different types of solar cells, solar dynamic), various construction and installation strategies (using terrestrial or extra-terrestrial resources) and the expected/required lifetime of the SPS are reviewed. The presented work is based on a 2-year study performed at the Technical University of Munich. The study showed that the main energy which is needed to make a solar power satellite a reality is required for the production of the solar power components (up to 65%), especially for the solar cell production. Whereas transport into orbit accounts in the order of 20% and the receiving station on earth (rectenna) requires about 15% of the total energy investment. The energetic amortization time, i.e. the time the SPS has to be operational to give back the amount of energy which was needed for its production installation and operation, is about two years.

Solar power satellite—Life-cycle energy recovery considerations

Science.gov (United States)

Weingartner, S.; Blumenberg, J.

1995-05-01

The construction, in-orbit installation and maintenance of a solar power satellite (SPS) will demand large amounts of energy. As a minimum requirement for an energy effective power satellite it is asked that this amount of energy be recovered. The energy effectiveness in this sense resulting in a positive net energy balance is a prerequisite for a cost-effective power satellite. This paper concentrates on life-cycle energy recovery instead of monetary aspects. The trade-offs between various power generation systems (different types of solar cells, solar dynamic), various construction and installation strategies (using terrestrial or extra-terrestrial resources) and the expected/required lifetime of the SPS are reviewed. The presented work is based on a 2-year study performed at the Technical University of Munich. The study showed that the main energy which is needed to make a solar power satellite a reality is required for the production of the solar power plant components (up to 65%), especially for the solar cell production. Whereas transport into orbit accounts in the order of 20% and the receiving station on Earth (rectenna) requires in the order of 15% of the total energy investment. The energetic amortization time, i.e. the time the SPS has to be operational to give back the amount of energy which was needed for its production, installation and operation, is in the order of two years.

Case Study of a Nearly Zero Energy Building in Italian Climatic Conditions

Directory of Open Access Journals (Sweden)

Hassan Saeed Khan

2017-11-01

Full Text Available The building sector is an important stakeholder in the energy and environmental scenario of any country. It continues to grow across the world due to factors such as population growth, and economic and infrastructure development. Within the European Union, buildings account for 40% of the total energy requirements and 30% of carbon dioxide emissions. The building sector is keen to improve its sustainability standards and also to help achieve the 20-20-20 targets set by the European Union. The present work aims to design a nearly zero energy sports gymnasium building in Calolziocorte, Italy. Various sustainability techniques are applied in an integrated design project approach using ECOTECT software to undertake the energy modelling exercise. Firstly, the base-case is modelled with conventional building materials and the total energy demand is calculated. Duly considering the local climatic conditions, sustainable materials are chosen for walls, the floor, the roof, and windows and a 38% reduction is noted in the total energy demand of the building compared to the base-case. The impact of louvers as a passive design technique has also been examined on the total energy demand of the building. The monthly load/discomfort analysis is undertaken for various individual functions inside the building to identify the critical areas that consume more energy. The monthly load/discomfort analysis is performed with the proposed materials and the air infiltration rate is improved through the building envelope and 63% reduction is noted in the total energy demand of the building compared to the base-case. A solar access analysis is conducted to understand the on-site energy production and then the building net energy demand is calculated, which is reduced to 90% compared to the base-case.

Zero energy growth for Canada: necessity and opportunity

Energy Technology Data Exchange (ETDEWEB)

Brooks, D B

1976-05-01

In resolving questions about the energy growth rate in Canada, two basic routes are possible: to allow costs and prices to adjust sufficiently to bring supply and demand into balance, presumably at a lower energy growth rate, or to adopt the normative propostion that some explicit choice should be made about target rates of energy consumption. This essay suggests that Canada should follow the latter route and that policies should be adopted to move Canada to a position close to zero energy growth by the year 2000. The thesis is that such a target is both feasible and desirable, with emphasis on the latter. Desirability is defined very broadly to include economic, social and environmental aspects. This essay attempts to answer basic questions about the nature of a low-energy alternative for Canada. In particular, energy conservation is associated with a larger construct called the conserver society, involving goals such as moderation in scale and in rates of change, emphasis on personal contact and community, and maintenance of a wide diversity of people and activities, as well as with the more obvious connotations of reduced material throughput and an improved environment. In this construct, zero energy growth is quite compatible with Canadian conditions that require major attention to space heating and a large transportation sector. Combined with the fact that the energy intended to be conserved includes all non-renewable energy and any other energy produced under capital-intensive, centralized conditions, but not small solar, biomass or wind plants, which can be accepted without destroying the conserver society values, it is felt that there is abundant energy for Canadians to live very well. 41 refs., 3 figs., 3 tabs.

Collecting Solar Energy. Solar Energy Education Project.

Science.gov (United States)

O'Brien, Alexander

This solar energy learning module for use with junior high school students offers a list of activities, a pre-post test, job titles, basic solar energy vocabulary, and diagrams of solar energy collectors and installations. The purpose is to familiarize students with applications of solar energy and titles of jobs where this knowledge could be…

Solar and Net Radiation for Estimating Potential Evaporation from Three Vegetation Canopies

Science.gov (United States)

D.M. Amatya; R.W. Skaggs; G.W. Cheschier; G.P. Fernandez

2000-01-01

Solar and net radiation data are frequent/y used in estimating potential evaporation (PE) from various vegetative surfaces needed for water balance and hydrologic modeling studies. Weather parameters such as air temperature, relative humidity, wind speed, solar radiation, and net radiation have been continuously monitored using automated sensors to estimate PE for...

Zero carbon energy system of South East Europe in 2050

International Nuclear Information System (INIS)

Dominković, D.F.; Bačeković, I.; Ćosić, B.; Krajačić, G.; Pukšec, T.; Duić, N.; Markovska, N.

2016-01-01

shares of 28.9% and 22.5%, followed by hydro power, concentrated solar power, biomass (mainly used in cogeneration units) and geothermal energy sources. To keep the biomass consumption within the sustainability limits, there is a need for some type of synthetic fuel in the transportation sector. Nevertheless, achieving 100% renewable energy system also promises to be financially beneficial, as the total calculated annual socio-economic cost of the region is approximately 20 billion euros lower in the year 2050 than in the base year. Finally, energy efficiency measures will play an important role in the transition to the zero-carbon energy society: the model shows that primary energy supply will be 50.9% lower than in the base year.

Initial Business Case Analysis of Two Integrated Heat Pump HVAC Systems for Near-Zero-Energy Homes

Energy Technology Data Exchange (ETDEWEB)

Baxter, Van D [ORNL

2006-11-01

The long range strategic goal of the Department of Energy's Building Technologies (DOE/BT) Program is to create, by 2020, technologies and design approaches that enable the construction of net-zero energy homes at low incremental cost (DOE/BT 2005). A net zero energy home (NZEH) is a residential building with greatly reduced needs for energy through efficiency gains, with the balance of energy needs supplied by renewable technologies. While initially focused on new construction, these technologies and design approaches are intended to have application to buildings constructed before 2020 as well resulting in substantial reduction in energy use for all building types and ages. DOE/BT's Emerging Technologies (ET) team is working to support this strategic goal by identifying and developing advanced heating, ventilating, air-conditioning, and water heating (HVAC/WH) technology options applicable to NZEHs. Although the energy efficiency of heating, ventilating, and air-conditioning (HVAC) equipment has increased substantially in recent years, new approaches are needed to continue this trend. Dramatic efficiency improvements are necessary to enable progress toward the NZEH goals, and will require a radical rethinking of opportunities to improve system performance. The large reductions in HVAC energy consumption necessary to support the NZEH goals require a systems-oriented analysis approach that characterizes each element of energy consumption, identifies alternatives, and determines the most cost-effective combination of options. In particular, HVAC equipment must be developed that addresses the range of special needs of NZEH applications in the areas of reduced HVAC and water heating energy use, humidity control, ventilation, uniform comfort, and ease of zoning. In FY05 ORNL conducted an initial Stage 1 (Applied Research) scoping assessment of HVAC/WH systems options for future NZEHs to help DOE/BT identify and prioritize alternative approaches for further

Life Cycle Cost Optimization of a BOLIG+ Zero Energy Building

DEFF Research Database (Denmark)

Marszal, Anna Joanna

. However, before being fully implemented in the national building codes and international standards, the ZEB concept requires a clear understanding and a uniform definition. The ZEB concept is an energy-conservation solution, whose successful adaptation in real life depends significantly on private...... building owners’ approach to it. For this particular target group, the cost is often an obstacle when investing money in environmental or climate friendly products. Therefore, this PhD project took the perspective of a future private ZEB owner to investigate the cost-optimal Net ZEB definition applicable...... in the Danish context. The review of the various ZEB approaches indicated a general concept of a Zero Energy Building as a building with significantly reduced energy demand that is balanced by an equivalent energy generation from renewable sources. And, with this as a general framework, each ZEB definition...

Comprehensive energy and economic analyses on a zero energy house versus a conventional house

Energy Technology Data Exchange (ETDEWEB)

Zhu, L. [School of Architecture, Tianjin University, Tianjin, 300072 (China); Hurt, R.; Correa, D.; Boehm, R. [Center for Energy Research, University of Nevada, Las Vegas, NV 89154 (United States)

2009-09-15

A zero energy house (ZEH) was built side by side with a baseline house in suburban Las Vegas. Actual energy performance measurements were carried out on the incorporated energy saving features and solar applications. The data show that a radiant barrier and a water-cooled air conditioner are major contributors to the energy savings, while an insulated floor slab and thermal mass walls are not effective for energy-conservation during cooling periods. Photovoltaic roof tiles produce enough green power to cover the use in the ZEH, and the solar water heater can reach a peak efficiency of 80%. The energy saving contribution of each incorporated component was obtained using Energy10 and eQUEST3.6 models, and then these codes were used for economic application evaluation. The two analysis codes yield similar results that compare well with the actual building performance data. Four items are clearly economically valuable for these applications: high performance windows, compact fluorescent lights, highly-insulated roofs and air conditioners with water-cooled condensers. PV tiles show a good financial return when rebates are considered. The Integrated Collector Storage (ICS) unit has a high efficiency but with a little higher thermal price. Thermal mass walls are too costly to have wide market appeal. (author)

Net-baryon-, net-proton-, and net-charge kurtosis in heavy-ion collisions within a relativistic transport approach

International Nuclear Information System (INIS)

Nahrgang, Marlene; Schuster, Tim; Stock, Reinhard; Mitrovski, Michael; Bleicher, Marcus

2012-01-01

We explore the potential of net-baryon, net-proton and net-charge kurtosis measurements to investigate the properties of hot and dense matter created in relativistic heavy-ion collisions. Contrary to calculations in a grand-canonical ensemble we explicitly take into account exact electric and baryon charge conservation on an event-by-event basis. This drastically limits the width of baryon fluctuations. A simple model to account for this is to assume a grand-canonical distribution with a sharp cut-off at the tails. We present baseline predictions of the energy dependence of the net-baryon, net-proton and net-charge kurtosis for central (b≤2.75 fm) Pb+Pb/Au+Au collisions from E lab =2A GeV to √(s NN )=200 GeV from the UrQMD model. While the net-charge kurtosis is compatible with values around zero, the net-baryon number decreases to large negative values with decreasing beam energy. The net-proton kurtosis becomes only slightly negative for low √(s NN ). (orig.)

STI/DOE Solar decathlon- Final Report

Energy Technology Data Exchange (ETDEWEB)

Washington, Gregory [Univ. of California, Irvine, CA (United States)

2016-04-14

Team Orange successfully designed and constructed a house driven by new design concepts and technical innovations that harmonize with Southern California’s lifestyle and respect its cultural heritage. The basic elements of our 2015 proposal can be summarized as follows: Increased emphasis on the passive solar design concept, with a visually stimulating design that enhances the Southern California lifestyle; Use of design and construction techniques to create a market-ready home for an efficient and affordable lifestyle; Integrated use of new technology to create a behavior-adaptive smart home; A zero net energy house complying with the Living Building philosophy; and compliance with all DOE Solar Decathlon requirements.

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)

Growth and solar energy conversion of Azolla sp., cultivated under four solar irradiance flux density; Crescimento e conversao da energia solar de Azolla sp. cultivada em quatro densidades do fluxo radiante

Energy Technology Data Exchange (ETDEWEB)

Carvalho, E.F. de [Acre Univ., Rio Branco, AC (Brazil); Lopes, N.F. [Vicosa Univ., MG (Brazil). Dept. de Biologia Vegetal

1994-02-01

Growth and solar energy conversion were studied in three Azolla species grown under four levels (30, 50, 70 and 100%) of solar radiation incidence under outdoor conditions. Under full sunlight, the specie A. microphylla showed higher crop growth rate, relative growth rate, net assimilation rate and efficiency of solar energy conversion than the other ones. (author). 8 figs., 23 refs.

Zero Energy Building

DEFF Research Database (Denmark)

Marszal, Anna Joanna; Heiselberg, Per; Bourrelle, J.S.

2011-01-01

The concept of Zero Energy Building (ZEB) has gained wide international attention during last few years and is now seen as the future target for the design of buildings. However, before being fully implemented in the national building codes and international standards, the ZEB concept requires......, (4) the type of energy balance, (5) the accepted renewable energy supply options, (6) the connection to the energy infrastructure and (7) the requirements for the energy efficiency, the indoor climate and in case of gird connected ZEB for the building–grid interaction. This paper focuses...

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).

Solar-energy-system performance evaluation: Honeywell OTS 44, Ocmulgee, Georgia

Science.gov (United States)

Mathur, A. K.; Pederson, S.

1982-01-01

The operation and technical performance of the solar operational test site (OTS 44) are described, based on data collected between April, 1981 and August, 1981. The following topics are discussed: system description, performance assessment, operating energy, energy savings, system maintenance, and conclusions. The solar energy system at OTS 44 is a hydronic heating and cooling system consisting of 5040 square feet of liquid cooled flat plate collectors; a 4000 gallon thermal storage tank; one 25 ton capacity organic Rankine cycle engine assisted water chillers; a forced draft cooling tower; and associated piping, pumps, valves, controls and heat rejection equipment. The solar system has eight basic modes of operation and several combination modes for providing space conditioning and hot water to the building. Data monitored during the 4 months of the operational test period found that the solar system collected 285 MMBtu of thermal energy of the total incident solar energy of 1040 MMBtu and provided 210 MMBtu for cooling and 10 MMBtu for heating and hot water. The net electrical energy saving due to the solar system was approximately 2600 kWh(e), and fossil energy saving was about 20 million Btu (MMBtu).

Zero Energy Districts

Energy Technology Data Exchange (ETDEWEB)

Polly, Benjamin J [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2018-05-04

This presentation shows how NREL is approaching Zero Energy Districts, including key opportunities, design strategies, and master planning concepts. The presentation also covers URBANopt, an advanced analytical platform for district that is being developed by NREL.

Increase of solar radiation due to climate change and its impact on solar energy use

International Nuclear Information System (INIS)

Kuhnke, K.; Rahme, A.; Harling, J.; Arensmann, R.

2008-01-01

Full text: There is a significant change in solar radiation in Central Europe coinciding with the IPCC climate change model calculations. The increase of yearly solar radiation on the horizontal surface is about 0.38 percent/year. On the other hand, photovoltaic solar modules show an ageing effect of the same order of magnitude, i.e. a reduction of yearly energy yield between 0.3 and 0.5 percent/year. This reduction is normally taken into account in economic calculations such as payback time and internal rate of interest. As the two trends of increase in radiation and ageing of solar modules are in opposite direction to each other, they will - with their uncertainties - neutralize one another to zero. Thus, the energy production of photovoltaic systems can be calculated without any deductions due to ageing in the future. (authors)

Solar Energy.

Science.gov (United States)

Eaton, William W.

Presented is the utilization of solar radiation as an energy resource principally for the production of electricity. Included are discussions of solar thermal conversion, photovoltic conversion, wind energy, and energy from ocean temperature differences. Future solar energy plans, the role of solar energy in plant and fossil fuel production, and…

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.

Zero-point energy in spheroidal geometries

OpenAIRE

Kitson, A. R.; Signal, A. I.

2005-01-01

We study the zero-point energy of a massless scalar field subject to spheroidal boundary conditions. Using the zeta-function method, the zero-point energy is evaluated for small ellipticity. Axially symmetric vector fields are also considered. The results are interpreted within the context of QCD flux tubes and the MIT bag model.

Reliability and energy efficiency of zero energy homes (Conference Presentation)

Science.gov (United States)

Dhere, Neelkanth G.

2016-09-01

Photovoltaic (PV) modules and systems are being installed increasingly on residential homes to increase the proportion of renewable energy in the energy mix. The ultimate goal is to attain sustainability without subsidy. The prices of PV modules and systems have declined substantially during the recent years. They will be reduced further to reach grid parity. Additionally the total consumed energy must be reduced by making the homes more energy efficient. FSEC/UCF Researchers have carried out research on development of PV cells and systems and on reducing the energy consumption in homes and by small businesses. Additionally, they have provided guidance on PV module and system installation and to make the homes energy efficient. The produced energy is fed into the utility grid and the consumed energy is obtained from the utility grid, thus the grid is assisting in the storage. Currently the State of Florida permits net metering leading to equal charge for the produced and consumed electricity. This paper describes the installation of 5.29 KW crystalline silicon PV system on a south-facing tilt at approximately latitude tilt on a single-story, three-bedroom house. It also describes the computer program on Building Energy Efficiency and the processes that were employed for reducing the energy consumption of the house by improving the insulation, air circulation and windows, etc. Finally it describes actual consumption and production of electricity and the installation of additional crystalline silicon PV modules and balance of system to make it a zero energy home.

Zero carbon energy system of South East Europe in 2050

DEFF Research Database (Denmark)

Dominkovic, Dominik Franjo; Bačeković, I.; Ćosić, B.

2016-01-01

and photovoltaics are the main technologies with shares of 28.9% and 22.5%, followed by hydro power, concentrated solar power, biomass (mainly used in cogeneration units) and geothermal energy sources. To keep the biomass consumption within the sustainability limits, there is a need for some type of synthetic fuel...... the integration of their energy systems is considered to be a challenging task. Large differences between energy mixes, still largely dominated by fossil-fuel consumption, make this task even more demanding.This paper presents the transition steps to a 100% renewable energy system which need to be carried out...... until the year 2050 in order to achieve zero carbon energy society. Novelty of this paper compared to other papers with similar research goals is the assumed sustainable use of biomass in the 100% renewable energy system of the region considered. It is important to emphasize here that only...

Very low energy homes in the United States: Perspectives on performance from measured data

Energy Technology Data Exchange (ETDEWEB)

Parker, Danny S. [Florida Solar Energy Center, 1679 Clearlake Rd., Cocoa, FL 32922 (United States)

2009-05-15

We present measured annual performance data from a dozen recent-vintage very low energy homes in North America. Many of the designs combine greater energy efficiency with solar electric photovoltaic power in an attempt to create Zero Energy Homes (ZEH). We also provide measured data from the first home constructed to the German Passivhaus standard in the United States. Several projects either exceeded or come very close to true net zero energy when evaluated over a year. The data indicate that very low energy use buildings can very readily be achieved in North America. Annual energy use half that or less than standard housing can be achieved for an equivalent cost of $0.10/kWh from the efficiency investment. In general, the better cost effectiveness seen from energy efficiency measures indicates that greater investment in conservation should be a prerequisite to installation of solar water heating and solar electricity in Zero Energy Homes. However, over emphasis in efficiency is also possible. This suggests that optimization tools such as BEopt and EGUSA, which characterize both renewable resource performance and that also of specific combinations of energy efficiency measures, will best guide designers to locate the most economically favorable mix to reach an energy neutral level. (author)

Solar energy

Science.gov (United States)

Rapp, D.

1981-01-01

The book opens with a review of the patterns of energy use and resources in the United States, and an exploration of the potential of solar energy to supply some of this energy in the future. This is followed by background material on solar geometry, solar intensities, flat plate collectors, and economics. Detailed attention is then given to a variety of solar units and systems, including domestic hot water systems, space heating systems, solar-assisted heat pumps, intermediate temperature collectors, space heating/cooling systems, concentrating collectors for high temperatures, storage systems, and solar total energy systems. Finally, rights to solar access are discussed.

Solar buildings program contract summary, calendar year 1999

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-06-07

The mission of the US Department of Energy's Solar Buildings Program is to advance the development and widespread deployment of competitive solar thermal technologies for use in buildings. The long-term goal of the Program is to combine solar energy technologies with energy-efficient construction techniques and create cost-effective buildings that have a zero net need for fossil fuel energy on an annual basis. The Solar Buildings Program conducts research and development on solar technologies that can deliver heat, light, and hot water to residential and commercial buildings. By working closely with manufacturers in both the buildings and solar energy industries and by supporting research at universities and national laboratories, the Solar Buildings Program brings together the diverse players developing reliable and affordable solar technologies for building applications. The National Renewable Energy Laboratory (NREL) in Golden, Colorado, and Sandia National Laboratories (SNL) in Albuquerque, New Mexico, jointly participate in the Solar Buildings Program. These two national laboratories work closely with industry researching new concepts, developing technology improvements, reducing manufacturing costs, monitoring system performance, promoting quality assurance, and identifying potential new markets. In calendar year 1999, the Solar Buildings Program focused primarily on solar hot water system research and development (R and D), US industry manufacturing assistance, and US market assistance. The Program also completed a number of other projects that were begun in earlier years. This Contract Summary describes the Program's contracted activities that were active during 1999.

Energy-Independent Architectural Models for Residential Complex Plans through Solar Energy in Daegu Metropolitan City, South Korea

Directory of Open Access Journals (Sweden)

Sung-Yul Kim

2018-02-01

Full Text Available This study suggests energy-independent architectural models for residential complexes through the production of solar-energy-based renewable energy. Daegu Metropolitan City, South Korea, was selected as the target area for the residential complex. An optimal location in the area was selected to maximize the production of solar-energy-based renewable energy. Then, several architectural design models were developed. Next, after analyzing the energy-use patterns of each design model, economic analyses were conducted considering the profits generated from renewable-energy use. In this way, the optimum residential building model was identified. For this site, optimal solar power generation efficiency was obtained when solar panels were installed at 25° angles. Thus, the sloped roof angles were set to 25°, and the average height of the internal space of the highest floor was set to 1.8 m. Based on this model, analyses were performed regarding energy self-sufficiency improvement and economics. It was verified that connecting solar power generation capacity from a zero-energy perspective considering the consumer’s amount of power consumption was more effective than connecting maximum solar power generation capacity according to building structure. Moreover, it was verified that selecting a subsidizable solar power generation capacity according to the residential solar power facility connection can maximize operational benefits.

Zero Energy Is an A+ for Education: Discovery Elementary

Energy Technology Data Exchange (ETDEWEB)

Torcellini, Paul A [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2017-08-09

Currently experiencing a population boom, Arlington County is facing massive growth in the next decade and is seeking to add half a million square feet in educational facilities. During competitive design procurement, one of the teams suggested a zero energy goal could be accomplished within the given budget. Proponents at the district level who had been championing energy efficiency were receptive because sustainability was a core value of the project from the start, but they were skeptical that it could be done within the budget aimed at LEED Silver. Not only did the project end up coming under budget, including the solar array, but the building is more efficient than the originally predicted. Now Discovery saves $100,000 per year in utility costs, enough to cover the salaries of two teachers.

Solar energy

International Nuclear Information System (INIS)

Kruisheer, N.

1992-01-01

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

Distributed energy resources for a zero-energy neighbhourhood

NARCIS (Netherlands)

Morales Gonzalez, R.M.D.G.; Asare-Bediako, B.; Cobben, J.F.G.; Kling, W.L.; Scharrenberg, G.R.; Dijkstra, D.

2012-01-01

Zero energy buildings are on the increasing trend. They are perceived as appropriate technology to reducing CO2 emissions, improving energy efficiency and alleviating energy poverty. The main goal is that a grid-connected building produces enough energy on site to equal or exceed its annual energy

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.

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.

Zero Energy Schools: Designing for the Future: Zero Energy Ready K-12 Schools

Energy Technology Data Exchange (ETDEWEB)

Torcellini, Paul A [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2017-09-29

Designing, building, and operating zero energy ready K-12 schools provides benefits for districts, students, and teachers. Optimizing energy efficiency is important in any building, but it's particularly important in K-12 schools. Many U.S. school districts struggle for funding, and improving a school building's energy efficiency can free up operational funds that may then be available for educational and other purposes.

Integrating rooftop solar into a multi-source energy planning optimization model

International Nuclear Information System (INIS)

Arnette, Andrew N.

2013-01-01

Highlights: • There is significant technical capacity for rooftop solar installations. • Rooftop solar generation is heavily dependent on key parameters. • Rooftop solar should be one of several options for increasing renewable energy. • Renewable energy planning should consider both cost and benefits. - Abstract: This research uses an optimization model to compare the role of rooftop solar generation versus large-scale solar and wind farm installations in renewable energy planning. The model consists of competing objectives, minimizing annual generation costs and minimizing annual greenhouse gas emissions. Rather than focus on the individual consumer’s investment decision, over 20 scenarios were developed which explored key input parameters such as the maximum penetration level of rooftop solar installations, pricing of equipment, tax credits, and net-metering policy to determine what role rooftop solar plays in renewable energy investment at an aggregate level. The research finds that at lower levels of penetration, such as those currently found in the United States, other renewable energy sources remain viable options, thus rooftop solar should be just one option considered when increasing development of renewable energy sources. The research also shows that a balanced approach taking into account both of the opposing objectives will lead to greater levels of rooftop solar generation than focusing solely on cost or emissions. Therefore, rooftop solar should be considered as part of an overall balanced approach to increasing renewable energy generation

Solar Energy Innovation Network | Solar Research | NREL

Science.gov (United States)

Energy Innovation Network Solar Energy Innovation Network The Solar Energy Innovation Network grid. Text version The Solar Energy Innovation Network is a collaborative research effort administered (DOE) Solar Energy Technologies Office to develop and demonstrate new ways for solar energy to improve

Solar energy

International Nuclear Information System (INIS)

Anon.

1992-01-01

This chapter discusses the role solar energy may have in the energy future of the US. The topics discussed in the chapter include the solar resource, solar architecture including passive solar design and solar collectors, solar-thermal concentrating systems including parabolic troughs and dishes and central receivers, photovoltaic cells including photovoltaic systems for home use, and environmental, health and safety issues

Demonstration of the Energy Component of the Installation Master Plan Using the Net Zero Energy Planner Tool: Cost and Performance Report

Science.gov (United States)

2015-12-11

These data come from Spatial Data Standards for Facilities, Infrastructure, and Environment (SDSFIE)-compliant GIS, usually obtained from the...solar photovoltaics, solar-thermal, wind energy, biomass (wood chips, etc.), biogas , or synthetic gas need to be considered as part of the mix during...results could be obtained . Both the SME team and the NZP team used an overlapping set of data, with the NZP team also requiring GIS data. Section 2

Analysis of solar radiation transfer: A method to estimate the porosity of a plastic shading net

International Nuclear Information System (INIS)

Abdel-Ghany, A.M.; Al-Helal, I.M.

2011-01-01

Plastic nets with opaque threads are frequently used for shading agricultural structures under high solar radiation conditions. A parameter that is often used to define a net is the net porosity (Π). Value of Π is usually estimated by one of three methods: image processing, direct beam transmittance, or solar radiation balance (hereafter radiation balance). Image processing is a rather slow process because it requires scanning the net sample at high resolution. The direct beam transmittance and radiation balance methods greatly overestimate Π because some of the solar radiation incident on the thread surfaces is forward scattered and add a considerable amount of radiation to that transmitted from the net pores directly. In this study, the radiation balance method was modified to estimate Π precisely. The amount of solar radiation scattered forward on the thread surfaces was estimated separately. Thus, the un-scattered solar radiation transmitted from the net pores directly, which describes the net porosity, Π could be estimated. This method, in addition to the image processing and the direct beam transmittance methods were used to estimate Π for different types of nets that are commonly used for shading structures in summer. Values of Π estimated by using the proposed method were in good accordance with those measured by the image processing method at a resolution of 4800 dpi. The direct beam transmittance and the radiation balance methods resulted in overestimation errors in the values of Π. This error strongly depends on the color of the net. The estimated errors were +14% for a green net and +37% for a white net when using the radiation balance method, and were +16% and +38%, respectively, when using the direct beam transmittance method. In the image processing method, a resolution of 2400 dpi is sufficient to estimate Π precisely and the higher resolutions showed no significant effect on the value of Π.

Solar energy collector

Science.gov (United States)

Brin, Raymond L.; Pace, Thomas L.

1978-01-01

The invention relates to a solar energy collector comprising solar energy absorbing material within chamber having a transparent wall, solar energy being transmitted through the transparent wall, and efficiently absorbed by the absorbing material, for transfer to a heat transfer fluid. The solar energy absorbing material, of generally foraminous nature, absorbs and transmits the solar energy with improved efficiency.

Technical and economic analysis of integrating low-medium temperature solar energy into power plant

International Nuclear Information System (INIS)

Wang, Fu; Li, Hailong; Zhao, Jun; Deng, Shuai; Yan, Jinyue

2016-01-01

Highlights: • Seven configurations were studied regarding the integration of solar thermal energy. • Economic analysis was conducted on new built plants and retrofitted power plants. • Using solar thermal energy to preheat high pressure feedwater shows the best performance. - Abstract: In order to mitigate CO_2 emission and improve the efficiency of the utilization of solar thermal energy (STE), solar thermal energy is proposed to be integrated into a power plant. In this paper, seven configurations were studied regarding the integration of STE. A 300 MWe subcritical coal-fired plant was selected as the reference, chemical absorption using monoethanolamine solvent was employed for CO_2 ​capture, and parabolic trough collectors and evacuated tube collectors were used for STE collection. Both technical analysis and economic evaluation were conducted. Results show that integrating solar energy with post-combustion CO_2​ capture can effectively increase power generation and reduce the electrical efficiency penalty caused by CO_2 capture. Among the different configurations, Config-2 and Config-6, which use medium temperature STE to replace high pressure feedwater without and with CO_2 capture, show the highest net incremental solar efficiency. When building new plants, integrating solar energy can effectively reduce the levelized cost of electricity (LCOE). The lowest LCOE, 99.28 USD/MWh, results from Config-6, with a parabolic trough collector price of 185 USD/m"2. When retrofitting existing power plants, Config-6 also shows the highest net present value (NPV), while Config-2 has the shortest payback time at a carbon tax of 50 USD/ton CO_2. In addition, both LCOE and NPV/payback time are clearly affected by the relative solar load fraction, the price of solar thermal collectors and the carbon tax. Comparatively, the carbon tax can affect the configurations with CO_2 capture more clearly than those without CO_2 capture.

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

Solar Energy Systems

Science.gov (United States)

1984-01-01

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

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

Science.gov (United States)

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

1981-10-01

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

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

Science.gov (United States)

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

1981-01-01

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

DOE Zero Energy Ready Home Case Study: The Imery Group — Proud Green Home, Serenbe, GA

Energy Technology Data Exchange (ETDEWEB)

none,

2014-09-01

The first certified Zero Energy Ready Home in Georgia was honored in the Custom Builder category of the 2014 Housing Innovation Awards. The 2,811-ft2, two-story custom home has 2x6 advanced framed walls filled with R-20 of open-cell spray foam, plus an R-6.6 insulated coated OSB sheathing. Also included is electronic monitoring equipment that tracks the PV, solar thermal water heater, ERV, mini-split heat pump with three indoor heads, solar water heater, and LED and CFL lighting.

Solar energy guide

International Nuclear Information System (INIS)

Lentz, A.; Winter, R.

1993-07-01

Many aspects with regard to the practical use of solar energy are discussed. This guide is aimed at informing local and regional administrators, committee members of housing corporations and public utilities and public relations officers on the possibilities to use solar energy. In chapter one an overview is given of the use of solar energy in the housing sector, the recreational sector, agricultural sector, industry, trade and other sectors. In the chapters two, three and four attention is paid to passive solar energy, active thermal solar energy and photovoltaic energy respectively. In the chapters five and six aspects concerning the implementation of solar energy systems in practice are discussed. First an outline of the parties involved in implementing solar energy is given: the municipality, the energy utility, the province, local authorities, advisors, housing constructors and the occupants of the buildings. Then attention is paid to the consequences of implementing solar energy for the building inspection and regulations, the finances, energy savings and the environment. In chapter seven an overview is given of the subsidy regulations of the European Community, the Dutch national and local governments. Chapter contains addresses of solar thermal systems, photovoltaic systems and other institutes operating in the field of solar energy, as well as the titles of a number of brochures and courses. 51 figs., 7 tabs., 86 refs

Tapping the zero-point energy as an energy source

International Nuclear Information System (INIS)

King, M.B.

1991-01-01

This paper reports that the hypothesis for tapping the zero-point energy (ZPE) arises by combining the theories of the ZPE with the theories of system self-organization. The vacuum polarization of atomic nuclei might allow their synchronous motion to activate a ZPE coherence. Experimentally observed plasma ion-acoustic anomalies as well as inventions utilizing cycloid ion motions may offer supporting evidence. The suggested experiment of rapidly circulating a charged plasma in a vortex ring might induce a sufficient zero-point energy interaction to manifest a gravitational anomaly. An invention utilizing abrupt E field rotation to create virtual charge exhibits excessive energy output

Modular Zero Energy. BrightBuilt Home

Energy Technology Data Exchange (ETDEWEB)

Aldrich, Robb [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States). Steven Winters Associates, Inc.; Butterfield, Karla [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States). Steven Winters Associates, Inc.

2016-03-01

Kaplan Thompson Architects (KTA) has specialized in sustainable, energy-efficient buildings, and they have designed several custom, zero-energy homes in New England. These zero-energy projects have generally been high-end, custom homes with budgets that could accommodate advanced energy systems. In an attempt to make zero energy homes more affordable and accessible to a larger demographic, KTA explored modular construction as way to provide high-quality homes at lower costs. In the mid-2013, KTA formalized this concept when they launched BrightBuilt Home (BBH). The BBH mission is to offer a line of architect-designed, high-performance homes that are priced to offer substantial savings off the lifetime cost of a typical home and can be delivered in less time. For the past two years, CARB has worked with BBH and Keiser Homes (the primary modular manufacturer for BBH) to discuss challenges related to wall systems, HVAC, and quality control. In Spring of 2014, CARB and BBH began looking in detail on a home to be built in Lincolnville, ME by Black Bros. Builders. This report details the solution package specified for this modular plan and the challenges that arose during the project.

Gravitational Zero Point Energy induces Physical Observables

OpenAIRE

Garattini, Remo

2010-01-01

We consider the contribution of Zero Point Energy on the induced Cosmological Constant and on the induced Electric/Magnetic charge in absence of matter fields. The method is applicable to every spherically symmetric background. Extensions to a generic $f(R) $ theory are also allowed. Only the graviton appears to be fundamental to the determination of Zero Point Energy.

Integrating net-zero energy and high-performance green building technologies into contemporary housing in a cold climate

Science.gov (United States)

Martin Yoklic; Mark Knaebe; Karen Martinson

2010-01-01

The objectives of this research project are (1) to show how the sustainable resources of forest biomass, solar energy, harvested rainwater, and small-diameter logs can be integrated to a system that provides most or all of the energy and water needs of a typical cold climate residential household, and (2) to effectively interpret the results and convey the sustainable...

Modeling the Economic Feasibility of Large-Scale Net-Zero Water Management: A Case Study.

Science.gov (United States)

Guo, Tianjiao; Englehardt, James D; Fallon, Howard J

  While municipal direct potable water reuse (DPR) has been recommended for consideration by the U.S. National Research Council, it is unclear how to size new closed-loop DPR plants, termed "net-zero water (NZW) plants", to minimize cost and energy demand assuming upgradient water distribution. Based on a recent model optimizing the economics of plant scale for generalized conditions, the authors evaluated the feasibility and optimal scale of NZW plants for treatment capacity expansion in Miami-Dade County, Florida. Local data on population distribution and topography were input to compare projected costs for NZW vs the current plan. Total cost was minimized at a scale of 49 NZW plants for the service population of 671,823. Total unit cost for NZW systems, which mineralize chemical oxygen demand to below normal detection limits, is projected at ~$10.83 / 1000 gal, approximately 13% above the current plan and less than rates reported for several significant U.S. cities.

Comparing energy payback and simple payback period for solar photovoltaic systems

Directory of Open Access Journals (Sweden)

Kessler Will

2017-01-01

Full Text Available Installing a solar photovoltaic (PV array is both an environmental and a financial decision. The financial arguments often take priority over the environmental because installing solar is capital-intensive. The Simple Payback period (SPB is often assessed prior to the adoption of solar PV at a residence or a business. Although it better describes the value of solar PV electricity in terms of sustainability, the Energy Payback period (EPB is seldom used to gauge the merits of an installation. Using published estimates of embodied energies, EPB was calculated for four solar PV plants utilizing crystalline-Si technology: three being actual commercial installations located in the northeastern U.S., and a fourth installation based on a simulated 20-kilowatt roof-mounted system, in Wrocław, Poland. Simple Payback was calculated based on initial capital cost, and on the availability of avoided electricity costs based on net-metering tariffs, which at present in the U.S. are 1:1 credit ratio, and in Poland is 1:0.7 credit ratio. For all projects, the EPB time was estimated at between 1.9 and 2.6 years. In contrast, the SPB for installed systems in the northeastern U.S. ranged from 13.3 to 14.6 years, and was estimated at 13.5 years for the example system in Lower Silesia, Poland. The comparison between SPB and EPB shows a disparity between motivational time frames, in which the wait for financial return is considerably longer than the wait for net energy harvest and the start of sustainable power production.

Comparing energy payback and simple payback period for solar photovoltaic systems

Science.gov (United States)

Kessler, Will

2017-11-01

Installing a solar photovoltaic (PV) array is both an environmental and a financial decision. The financial arguments often take priority over the environmental because installing solar is capital-intensive. The Simple Payback period (SPB) is often assessed prior to the adoption of solar PV at a residence or a business. Although it better describes the value of solar PV electricity in terms of sustainability, the Energy Payback period (EPB) is seldom used to gauge the merits of an installation. Using published estimates of embodied energies, EPB was calculated for four solar PV plants utilizing crystalline-Si technology: three being actual commercial installations located in the northeastern U.S., and a fourth installation based on a simulated 20-kilowatt roof-mounted system, in Wrocław, Poland. Simple Payback was calculated based on initial capital cost, and on the availability of avoided electricity costs based on net-metering tariffs, which at present in the U.S. are 1:1 credit ratio, and in Poland is 1:0.7 credit ratio. For all projects, the EPB time was estimated at between 1.9 and 2.6 years. In contrast, the SPB for installed systems in the northeastern U.S. ranged from 13.3 to 14.6 years, and was estimated at 13.5 years for the example system in Lower Silesia, Poland. The comparison between SPB and EPB shows a disparity between motivational time frames, in which the wait for financial return is considerably longer than the wait for net energy harvest and the start of sustainable power production.

Solar Energy Technician/Installer

Science.gov (United States)

Moore, Pam

2007-01-01

Solar power (also known as solar energy) is solar radiation emitted from the sun. Large panels that absorb the sun's energy as the sun beats down on them gather solar power. The energy in the rays can be used for heat (solar thermal energy) or converted to electricity (photovoltaic energy). Each solar energy project, from conception to…

Application of nanomaterials in solar thermal energy storage

Science.gov (United States)

Shamshirgaran, Seyed Reza; Khalaji Assadi, Morteza; Viswanatha Sharma, Korada

2018-06-01

Solar thermal conversion technology harvests the sun's energy, rather than fossil fuels, to generate low-cost, low/zero-emission energy in the form of heating, cooling or electrical form for residential, commercial, and industrial sectors. The advent of nanofluids and nanocomposites or phase change materials, is a new field of study which is adapted to enhance the efficiency of solar collectors. The concepts of thermal energy storage technologies are investigated and the role of nanomaterials in energy conversion is discussed. This review revealed that although the exploitation of nanomaterials will boost the performance of solar collectors almost in all cases, this would be accompanied by certain challenges such as production cost, instability, agglomeration and erosion. Earlier studies have dealt with the enhancement of thermal conductivity and heat capacity; however, less attention has been given to the facing challenges. Moreover, no exact criteria can be found for the selection of appropriate nanomaterials and their properties for a specific application. In most research studies, the nanoparticles' material and properties have not been selected based on estimated values so that all the aspects of desired application could be considered simultaneously. The wide spread use of nanomaterials can lead to cost effective solutions as well. Therefore, it seems there should be a sense of techno-economic optimization in exploiting nanomaterials for solar thermal energy storage applications. The optimization should cover the key parameters, particularly nanoparticle type, size, loading and shape which depends on the sort of application and also dispersion technology.

Application of nanomaterials in solar thermal energy storage

Science.gov (United States)

Shamshirgaran, Seyed Reza; Khalaji Assadi, Morteza; Viswanatha Sharma, Korada

2017-12-01

Solar thermal conversion technology harvests the sun's energy, rather than fossil fuels, to generate low-cost, low/zero-emission energy in the form of heating, cooling or electrical form for residential, commercial, and industrial sectors. The advent of nanofluids and nanocomposites or phase change materials, is a new field of study which is adapted to enhance the efficiency of solar collectors. The concepts of thermal energy storage technologies are investigated and the role of nanomaterials in energy conversion is discussed. This review revealed that although the exploitation of nanomaterials will boost the performance of solar collectors almost in all cases, this would be accompanied by certain challenges such as production cost, instability, agglomeration and erosion. Earlier studies have dealt with the enhancement of thermal conductivity and heat capacity; however, less attention has been given to the facing challenges. Moreover, no exact criteria can be found for the selection of appropriate nanomaterials and their properties for a specific application. In most research studies, the nanoparticles' material and properties have not been selected based on estimated values so that all the aspects of desired application could be considered simultaneously. The wide spread use of nanomaterials can lead to cost effective solutions as well. Therefore, it seems there should be a sense of techno-economic optimization in exploiting nanomaterials for solar thermal energy storage applications. The optimization should cover the key parameters, particularly nanoparticle type, size, loading and shape which depends on the sort of application and also dispersion technology.

DOE Zero Energy Ready Home Case Study: United Way of Long Island, United Veterans Beacon House

Energy Technology Data Exchange (ETDEWEB)

Pacific Northwest National Laboratory

2017-09-01

United Way of Long Island’s Housing Development Corporation built this 3,719-ft2 two–story, 5-bedroom home in Huntington Station, New York, to the rigorous performance requirements of the U.S. Department of Energy’s Zero Energy Ready Home Program. The home is packed with high-performance features like LED lighting and ENERGY STAR appliances. The asymmetrical, optimally angled roof provides plenty of space for roof-mounted solar panels for electric generation and hot water.

DOE Zero Energy Ready Home Case Study: Amaris Custom Homes, St. Paul, Minnesota

Energy Technology Data Exchange (ETDEWEB)

None

2015-06-01

For this project, Amaris worked with U.S. Department of Energy (DOE) team, NorthernSTAR Building America Partnership, to develop the first Zero Energy Ready Home (ZERH) in Minnesota's cold climate using reasonable, cost-effective, and replicable construction materials and practices. The result is a passive solar, super-efficient 3542-ft2 walkout ranch-style home with all the creature comforts. Along with meeting ZERH standards, Amaris also achieved certifications for Leadership in Energy & Environmental Design for Homes v4, MN Green Path Emerald, and a Builders Association of the Twin Cities Reggie Award of Excellence. The home achieves a HERS score of 41 without photovoltaics; with PV, the home achieves a HERS score of 5.

Solar energy modulator

Science.gov (United States)

Hale, R. R. (Inventor); Mcdougal, A. R.

1984-01-01

A module is described with a receiver having a solar energy acceptance opening and supported by a mounting ring along the optic axis of a parabolic mirror in coaxial alignment for receiving solar energy from the mirror, and a solar flux modulator plate for varying the quantity of solar energy flux received by the acceptance opening of the module. The modulator plate is characterized by an annular, plate-like body, the internal diameter of which is equal to or slightly greater than the diameter of the solar energy acceptance opening of the receiver. Slave cylinders are connected to the modulator plate for supporting the plate for axial displacement along the axis of the mirror, therby shading the opening with respect to solar energy flux reflected from the surface of the mirror to the solar energy acceptance opening.

Renewable energy worldwide outlooks: solar energy

International Nuclear Information System (INIS)

Darnell, J.R.

1994-01-01

Solar energy yield is weak because it is very diffuse. The solar energy depends on the weather. The collectors need the beam radiation. Wavelength is important for some applications that include not only the visible spectrum but also infrared and ultraviolet radiation. The areas of the greatest future population growth are high on solar energy resources. We have different types of conversion systems where energy can be converted from solar to electric or thermal energy. Photovoltaic cells are made of silicone or gallium arsenide, this latter for the space use. For the solar energy applications there is a storage problem: electric batteries or superconducting magnets. Today, the highest use of solar energy is in the low temperature thermal category with over 90% of the world contribution from this energy. The penetration of solar energy will be higher in rural areas than in urban regions. But there are technical, institutional, economic constraints. In spite of that the use of solar energy would be increasing and will go on to increase thereafter. The decreasing costs over time are a real phenomenon and there is a broad public support for increased use of that energy. 15 figs

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

Turbulent Convection Insights from Small-Scale Thermal Forcing with Zero Net Heat Flux at a Horizontal Boundary.

Science.gov (United States)

Griffiths, Ross W; Gayen, Bishakhdatta

2015-11-13

A large-scale circulation, a turbulent boundary layer, and a turbulent plume are noted features of convection at large Rayleigh numbers under differential heating on a single horizontal boundary. These might be attributed to the forcing, which in all studies has been limited to a unidirectional gradient over the domain scale. We instead apply forcing on a length scale smaller than the domain, and with variation in both horizontal directions. Direct numerical simulations show turbulence throughout the domain, a regime transition to a dominant domain-scale circulation, and a region of logarithmic velocity in the boundary layer, despite zero net heat flux. The results show significant similarities to Rayleigh-Bénard convection, demonstrate the significance of plume merging, support the hypothesis that the key driver of convection is the production of available potential energy without necessarily supplying total potential energy, and imply that contributions to domain-scale circulation in the oceans need not be solely from the large-scale gradients of forcing.

Zero-biased solar-blind photodetector based on ZnBeMgO/Si heterojunction

International Nuclear Information System (INIS)

Yang, C; Li, X M; Yu, W D; Gao, X D; Cao, X; Li, Y Z

2009-01-01

An n-type Zn 1-x-y Be x Mg y O thin film was deposited on a p-type Si substrate by pulsed laser deposition to obtain a solar-blind photodetector. The spectral response characteristic with a cutoff wavelength of 280 nm was demonstrated to realize the photodetection of the solar-blind wave zone. The responsivity of the device was improved by inserting an Al-doped ZnO (AZO) contact layer, which was expected to enhance the carrier collection efficiency significantly. Correspondingly, the peak responsivity was improved from 0.003 to 0.11 A W -1 at zero bias, and a high external quantum efficiency of 53% at 270 nm was achieved. The fast rise time reached 20 ns. This work demonstrated the possibility of a wurtzite ZnO based oxide system to realize high performance zero-biased solar-blind photodetectors. (fast track communication)

COllaboration for Housing Nearly Zero-Energy RENOvation : Publishable Report

NARCIS (Netherlands)

Straub, A.

The building stock has a big importance in reaching Europe’s climate goals. The Energy Performance of Buildings Directive therefore states the need for nearly zero-energy buildings. Nearly zero-energy buildings are a key aspect to reduce the energy use of the built environment. Since a large share

Zero-point energy in early quantum theory

International Nuclear Information System (INIS)

Milonni, P.W.; Shih, M.-L.

1991-01-01

In modern physics the vacuum is not a tranquil void but a quantum state with fluctuations having observable consequences. The present concept of the vacuum has its roots in the zero-point energy of harmonic oscillators and the electromagnetic field, and arose before the development of the formalism of quantum mechanics. This article discusses these roots in the blackbody research of Planck and Einstein in 1912--1913, and the relation to Bose--Einstein statistics and the first indication of wave--particle duality uncovered by Einstein's fluctuation formula. Also considered are the Einstein--Stern theory of specific heats, which invoked zero-point energy in a way which turned out to be incorrect, and the experimental implications of zero-point energy recognized by Mulliken and Debye in vibrational spectroscopy and x-ray diffraction

Surface Net Solar Radiation Estimated from Satellite Measurements: Comparisons with Tower Observations

Science.gov (United States)

Li, Zhanqing; Leighton, H. G.; Cess, Robert D.

1993-01-01

A parameterization that relates the reflected solar flux at the top of the atmosphere to the net solar flux at the surface in terms of only the column water vapor amount and the solar zenith angle was tested against surface observations. Net surface fluxes deduced from coincidental collocated satellite-measured radiances and from measurements from towers in Boulder during summer and near Saskatoon in winter have mean differences of about 2 W/sq m, regardless of whether the sky is clear or cloudy. Furthermore, comparisons between the net fluxes deduced from the parameterization and from surface measurements showed equally good agreement when the data were partitioned into morning and afternoon observations. This is in contrast to results from an empirical clear-sky algorithm that is unable to account adequately for the effects of clouds and that shows, at Boulder, a distinct morning to afternoon variation, which is presumably due to the predominance of different cloud types throughout the day. It is also demonstrated that the parameterization may be applied to irradiances at the top of the atmosphere that have been temporally averaged by using the temporally averaged column water vapor amount and the temporally averaged cosine of the solar zenith angle. The good agreement between the results of the parameterization and surface measurements suggests that the algorithm is a useful tool for a variety of climate studies.

A combined cycle utilizing LNG and low-temperature solar energy

International Nuclear Information System (INIS)

Rao, Wen-Ji; Zhao, Liang-Ju; Liu, Chao; Zhang, Mo-Geng

2013-01-01

This paper has proposed a combined cycle, in which low-temperature solar energy and cold energy of liquefied natural gas (LNG) can be effectively utilized together. Comparative analysis based on a same net work output between the proposed combined cycle and separated solar ORC and LNG vapor system has been done. The results show that, for the combined cycle, a decrease of nearly 82.2% on the area of solar collector is obtained and the area of heat exchanger decreases by 31.7%. Moreover, exergy efficiency is higher than both two separated systems. This work has also dealt with the thermodynamic analyses for the proposed cycle. The results show that R143a followed by propane and propene emerges as most suitable fluid. Moreover, with a regenerator added in the cycle, performance improvement is obtained for the reduction on area of solar collector and increase on system efficiency and exergy efficiency. -- Highlights: • A combined cycle utilizing low-temperature solar energy and LNG together is proposed. • Five objection functions are used to decide the best working fluids. • Cycle with a regenerator has good performance

A Solar Chimney for renewable energy production: thermo-fluid dynamic optimization by CFD analyses

Science.gov (United States)

Montelpare, S.; D'Alessandro, V.; Zoppi, A.; Costanzo, E.

2017-11-01

This paper analyzes the performance of a solar tower designed for renewable energy production. The Solar Chimney Power Plant (SCPP) involves technology that converts solar energy by means of three basic components: a large circular solar collector, a high tower in the center of the collector and a turbine generator inside the chimney. SCPPs are characterized by long term operational life, low maintenance costs, zero use of fuels, no use of water and no emissions of greenhouse gases. The main problem of this technology is the low energy global conversion coefficient due to the presence of four conversions: solar radiation > thermal energy > kinetic energy > mechanical energy > electric energy. This paper defines its starting point from the well known power plant of Manzanares in order to calibrate a numerical model based on finite volumes. Following that, a solar tower with reduced dimensions was designed and an analysis on various geometric parameters was conducted: on the inlet section, on the collector slope, and on the fillet radius among the SUPP sections. Once the optimal solution was identified, a curved deflectors able to induce a flow swirl along the vertical tower axis was designed.

Zero Point Energy and the Dirac Equation

OpenAIRE

Forouzbakhsh, Farshid

2007-01-01

Zero Point Energy (ZPE) describes the random electromagnetic oscillations that are left in the vacuum after all other energy has been removed. One way to explain this is by means of the uncertainty principle of quantum physics, which implies that it is impossible to have a zero energy condition.I this article, the ZPE is explained by using a novel description of the graviton. This is based on the behavior of photons in gravitational field, leading to a new definition of the graviton. In effec...

Solar thermal energy conversion to electrical power

International Nuclear Information System (INIS)

Trinh, Anh-Khoi; González, Ivan; Fournier, Luc; Pelletier, Rémi; Sandoval V, Juan C.; Lesage, Frédéric J.

2014-01-01

The conversion of solar energy to electricity currently relies primarily on the photovoltaic effect in which photon bombardment of photovoltaic cells drives an electromotive force within the material. Alternatively, recent studies have investigated the potential of converting solar radiation to electricity by way of the Seebeck effect in which charge carrier mobility is generated by an asymmetric thermal differential. The present study builds upon these latest advancements in the state-of-the-art of thermoelectric system management by combining solar evacuated tube technology with commercially available Bismuth Telluride semiconductor modules. The target heat source is solar radiation and the target heat sink is thermal convection into the ambient air relying on wind aided forced convection. These sources of energy are reproduced in a laboratory controlled environment in order to maintain a thermal dipole across a thermoelectric module. The apparatus is then tested in a natural environment. The novelty of the present work lies in a net thermoelectric power gain for ambient environment applications and an experimental validation of theoretical electrical characteristics relative to a varying electrical load. - Highlights: • Solar radiation maintains a thermal tension which drives an electromotive force. • Voltage, current and electric power are reported and discussed. • Theoretical optimal thermoelectric conversion predictions are presented. • Theory is validated with experimentally measured data

Surface net solar radiation estimated from satellite measurements - Comparisons with tower observations

Science.gov (United States)

Li, Zhanqing; Leighton, H. G.; Cess, Robert D.

1993-01-01

A parameterization that relates the reflected solar flux at the top of the atmosphere to the net solar flux at the surface in terms of only the column water vapor amount and the solar zenith angle was tested against surface observations. Net surface fluxes deduced from coincidental collocated satellite-measured radiances and from measurements from towers in Boulder during summer and near Saskatoon in winter have mean differences of about 2 W/sq m, regardless of whether the sky is clear or cloudy. Furthermore, comparisons between the net fluxes deduced from the parameterization and from surface measurements showed equally good agreement when the data were partitioned into morning and afternoon observations. This is in contrast to results from an empirical clear-sky algorithm that is unable to account adequately for the effects of clouds and that shows, at Boulder, a distinct morning to afternoon variation. It is also demonstrated that the parameterization may be applied to irradiances at the top of the atmosphere that have been temporally averaged. The good agreement between the results of the parameterization and surface measurements suggests that the algorithm is a useful tool for a variety of climate studies.

Zero Energy Schools: Architects Take the Lead

Energy Technology Data Exchange (ETDEWEB)

Torcellini, Paul A [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2017-09-28

Zero energy schools are possible and practical, and architects are leading the way. Imagine a school so inviting that students want to come to school. Now imagine this school housed in a beautiful, light-filled building that produces more energy on an annual basis than it uses. Finally, imagine that the district built this school on the same budget as a conventional school, using typical materials, equipment, and tradespeople. Sound too good to be true Discovery Elementary School in Arlington, Virginia, is living proof that zero energy (ZE) schools are feasible, affordable, and sensible.

Techno-economic assessment of a solar PV, fuel cell, and biomass gasifier hybrid energy system

Directory of Open Access Journals (Sweden)

Anand Singh

2016-11-01

Full Text Available The interest of power is expanding step by step all through the world. Because of constrained measure of fossil fuel, it is vital to outline some new non-renewable energy frameworks that can diminish the reliance on ordinary energy asset. A hybrid off-grid renewable energy framework might be utilized to reduction reliance on the traditional energy assets. Advancement of crossover framework is a procedure to choose the best mix of part and there cost that can give shabby, solid and successful option energy resource. In this paper sun oriented photovoltaic, fuel cell, biomass gasifier generator set, battery backup and power conditioning unit have been simulated and optimized for educational institute, energy centre, Maulana Azad National Institute of Technology, Bhopal in the Indian state of Madhya Pradesh. The area of the study range on the guide situated of 23°12′N latitude and 77°24′E longitude. In this framework, the essential wellspring of power is sun based solar photovoltaic system and biomass gasifier generator set while fuel cell and batteries are utilized as reinforcement supply. HOMER simulator has been utilized to recreate off the grid and it checks the specialized and financial criteria of this hybrid energy system. The execution of every segment of this framework is dissected lastly delicate examination has been performing to enhance the mixture framework at various conditions. In view of the recreation result, it is found that the cost of energy (COE of a biomass gasifier generator set, solar PV and fuel cell crossover energy system has been found to be 15.064 Rs/kWh and complete net present cost Rs.51,89003. The abundance power in the proposed framework is observed to be 36 kWh/year with zero rates unmet electrical burden.

Competitiveness of grid-connected solar electricity in Sweden - as seen from the perspective of the utilities and the net owners; Konkurrenskraft foer naetansluten solel i Sverige - sett ur kraftfoeretagens och naetaegarnas perspektiv

Energy Technology Data Exchange (ETDEWEB)

Carlstedt, Nils-Eric [Vattenfall Power Consultant AB, Stockholm (Sweden); Karlsson, Bjoern; Kjellsson, Elisabeth; Samuelsson, Olof [Faculty of Engineering (LTH), Lund University, Lund (Sweden); Neij, Lena [International Institute for Industrial Environmental Economics, Lund University, Lund (Sweden)

2006-12-15

The objective of this report was to analyse the competitiveness of grid-connected solar power in Sweden - and specifically the competitiveness for energy companies and net owners. In theory, solar power could to a large extent fulfil the electricity demand in Sweden, especially in the summer. However, the high cost of solar cells is a major barrier to implementation. Future technology development and increased efficiency could, however, lead to important cost reductions. The question is if such expected cost reductions would make grid-connected solar power a preferable investment option for energy companies and an interesting alternative for the net owners. The results of the study show that solar power will not be a competitive alternative for the energy companies in Sweden, not in 2020 and probably not in 2050. Other alternatives such as new investments in wind turbines and bio-mass based technology options will be producing electricity at a lower cost. Moreover, solar power will have an unfavourable production profile, generating power in the summertime when less needed. However, by using the reservoirs of the hydro power systems in Sweden as storage capacity, approximately 5 TWh solar power could be allowed in the Swedish electricity system. The results of the study indicate that solar power could have a positive effect on the electricity distribution system since distributed generation will result in lower losses in the system. Moreover, solar power will be produced during daytime when the electricity demand will peak. One of the main challenges for the net owners would be to design the net in such a way that the net and the solar cells could work together in the best possible way. Another challenge would be the high cost for connecting the solar cells to the grid; this cost needs to be reduced. Looking instead at the house-owners as possible investors, solar cells appear as a much more attractive alternative for the future, the value of the solar power is

Integrated Heat Pump HVAC Systems for Near-Zero-Energy Homes - Business Case Assessment

Energy Technology Data Exchange (ETDEWEB)

Baxter, Van D [ORNL

2007-05-01

The long range strategic goal of the Department of Energy's Building Technologies (DOE/BT) Program is to create, by 2020, technologies and design approaches that enable the construction of net-zero energy homes at low incremental cost (DOE/BT 2005). A net zero energy home (NZEH) is a residential building with greatly reduced needs for energy through efficiency gains, with the balance of energy needs supplied by renewable technologies. While initially focused on new construction, these technologies and design approaches are intended to have application to buildings constructed before 2020 as well resulting in substantial reduction in energy use for all building types and ages. DOE/BT's Emerging Technologies (ET) team is working to support this strategic goal by identifying and developing advanced heating, ventilating, air-conditioning, and water heating (HVAC/WH) technology options applicable to NZEHs. Although the energy efficiency of heating, ventilating, and air-conditioning (HVAC) equipment has increased substantially in recent years, new approaches are needed to continue this trend. Dramatic efficiency improvements are necessary to enable progress toward the NZEH goals, and will require a radical rethinking of opportunities to improve system performance. The large reductions in HVAC energy consumption necessary to support the NZEH goals require a systems-oriented analysis approach that characterizes each element of energy consumption, identifies alternatives, and determines the most cost-effective combination of options. In particular, HVAC equipment must be developed that addresses the range of special needs of NZEH applications in the areas of reduced HVAC and water heating energy use, humidity control, ventilation, uniform comfort, and ease of zoning. In FY05 ORNL conducted an initial Stage 1 (Applied Research) scoping assessment of HVAC/WH systems options for future NZEHs to help DOE/BT identify and prioritize alternative approaches for further

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

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...

Zero-point energy of confined fermions

International Nuclear Information System (INIS)

Milton, K.A.

1980-01-01

A closed form for the reduced Green's function of massless fermions in the interior of a spherical bag is obtained. In terms of this Green's function, the corresponding zero-point or Casimir energy is computed. It is proposed that a resulting quadratic divergence can be absorbed by renormalizing a suitable parameter in the bag model (that is, absorbed by a contact term). The residual Casimir stress is attractive, but smaller than the repulsive Casimir stress of gluons in the model. The result for the total zero-point energy is in substantial disagreement with bag model phenomenological values

North European Understanding of Zero Energy/Emission Buildings

DEFF Research Database (Denmark)

Marszal, Anna Joanna; Bourrelle, J. S.; Nieminen, J.

2010-01-01

countries are still to adopt a national definition for these types of buildings. This results often in more than one understanding of ZEBs in each country. This study provides a concise source of information on the north European understanding of zero energy/emission buildings. It puts forward a number......The worldwide CO2 emission mitigation efforts, the growing energy resource shortage and the fact that buildings are responsible for a large share of the world’s primary energy use drives research towards new building concepts, in particular Zero Energy/Emission Buildings (ZEBs). Unfortunately...... may observe a correlation between the zero energy/emission building approach adopted by a country and this particular country’s utility grid characteristics. Moreover, it is to be noted that the ZEB concept is not well defined at the national level in northern Europe and that all of the participating...

Zero-reabsorption doped-nanocrystal luminescent solar concentrators.

Science.gov (United States)

Erickson, Christian S; Bradshaw, Liam R; McDowall, Stephen; Gilbertson, John D; Gamelin, Daniel R; Patrick, David L

2014-04-22

Optical concentration can lower the cost of solar energy conversion by reducing photovoltaic cell area and increasing photovoltaic efficiency. Luminescent solar concentrators offer an attractive approach to combined spectral and spatial concentration of both specular and diffuse light without tracking, but they have been plagued by luminophore self-absorption losses when employed on practical size scales. Here, we introduce doped semiconductor nanocrystals as a new class of phosphors for use in luminescent solar concentrators. In proof-of-concept experiments, visibly transparent, ultraviolet-selective luminescent solar concentrators have been prepared using colloidal Mn(2+)-doped ZnSe nanocrystals that show no luminescence reabsorption. Optical quantum efficiencies of 37% are measured, yielding a maximum projected energy concentration of ∼6× and flux gain for a-Si photovoltaics of 15.6 in the large-area limit, for the first time bounded not by luminophore self-absorption but by the transparency of the waveguide itself. Future directions in the use of colloidal doped nanocrystals as robust, processable spectrum-shifting phosphors for luminescent solar concentration on the large scales required for practical application of this technology are discussed.

Solar energy an introduction

CERN Document Server

Mackay, Michael E

2015-01-01

Solar Energy presents an introduction to all aspects of solar energy, from photovoltaic devices to active and passive solar thermal energy conversion, giving both a detailed and broad perspective of the field. It is aimed at the beginner involved in solar energy or a related field, or for someone wanting to gain a broader perspective of solar energy technologies. A chapter considering solar radiation, basic principles applied to solar energy, semiconductor physics, and light absorption brings the reader on equal footing with the technology of either solar generated electrical current or useful heat. Details of how a solar cell works and then production of current from a photovoltaic device is discussed. Characterization of a solar cell is examined, allowing one the ability to interpret the current-voltage relation, followed by discussion of parameter extraction from this relation. This information can be used to understand what limits the performance of a given solar cell with the potential to optimize its pe...

Solar Energy Basics | NREL

Science.gov (United States)

Solar Energy Basics Solar Energy Basics Solar is the Latin word for sun-a powerful source of energy that can be used to heat, cool, and light our homes and businesses. That's because more energy from the technologies convert sunlight to usable energy for buildings. The most commonly used solar technologies for

Bound states in string nets

Science.gov (United States)

Schulz, Marc Daniel; Dusuel, Sébastien; Vidal, Julien

2016-11-01

We discuss the emergence of bound states in the low-energy spectrum of the string-net Hamiltonian in the presence of a string tension. In the ladder geometry, we show that a single bound state arises either for a finite tension or in the zero-tension limit depending on the theory considered. In the latter case, we perturbatively compute the binding energy as a function of the total quantum dimension. We also address this issue in the honeycomb lattice where the number of bound states in the topological phase depends on the total quantum dimension. Finally, the internal structure of these bound states is analyzed in the zero-tension limit.

Solar Energy and You.

Science.gov (United States)

Conservation and Renewable Energy Inquiry and Referral Service (DOE), Silver Spring, MD.

This booklet provides an introduction to solar energy by discussing: (1) how a home is heated; (2) how solar energy can help in the heating process; (3) the characteristics of passive solar houses; (4) the characteristics of active solar houses; (5) how solar heat is stored; and (6) other uses of solar energy. Also provided are 10 questions to…

Zero-point energy and the Eoetvoes experiment

International Nuclear Information System (INIS)

Ross, D.K.

1999-01-01

The paper shows that the modification of the electromagnetic zero-point energy inside a solid aluminum ball ia large enough to be detected by a feasible Eoetvoes-type experiment improved only a factor of 100 over earlier experiments. Because of the uncertainties surrounding the relationship of the zero-point energy to the cosmological constant and to renormalization effects in general relativity that such an experiment might give a non-null result. This would be a test of the weak equivalence principle and of general relativity itself in regard to a very special purely quantum-mechanical form of energy

Designing Holistic Zero Energy Homes in Denmark

DEFF Research Database (Denmark)

Bejder, Anne Kirkegaard; Knudstrup, Mary-Ann

2016-01-01

Designing zero-energy buildings (ZEB) is a complex but not an impossible task, which has also been illustrated through demonstration projects, including houses that produce as much energy as they use on a yearly basis. Over the last years an increased interest for ZEBs is also seen in practice......, however, designing ZEBs is still challenging. In order to gain further currency, we need to collect new knowledge and communicate it in an easy applicable way for the building industry. This paper presents the development and objectives of a publication entitled “Zero Energy Buildings – Design Principles...

Program Design Analysis using BEopt Building Energy Optimization Software: Defining a Technology Pathway Leading to New Homes with Zero Peak Cooling Demand; Preprint

Energy Technology Data Exchange (ETDEWEB)

Anderson, R.; Christensen, C.; Horowitz, S.

2006-08-01

An optimization method based on the evaluation of a broad range of different combinations of specific energy efficiency and renewable-energy options is used to determine the least-cost pathway to the development of new homes with zero peak cooling demand. The optimization approach conducts a sequential search of a large number of possible option combinations and uses the most cost-effective alternatives to generate a least-cost curve to achieve home-performance levels ranging from a Title 24-compliant home to a home that uses zero net source energy on an annual basis. By evaluating peak cooling load reductions on the least-cost curve, it is then possible to determine the most cost-effective combination of energy efficiency and renewable-energy options that both maximize annual energy savings and minimize peak-cooling demand.

Technical Feasibility Study for Zero Energy K-12 Schools

Energy Technology Data Exchange (ETDEWEB)

Bonnema, Eric [National Renewable Energy Lab. (NREL), Golden, CO (United States); Goldwasser, David [National Renewable Energy Lab. (NREL), Golden, CO (United States); Torcellini, Paul [National Renewable Energy Lab. (NREL), Golden, CO (United States); Pless, Shanti [National Renewable Energy Lab. (NREL), Golden, CO (United States); Studer, Daniel [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-11-01

This technical feasibility study provides documentation and research results supporting a possible set of strategies to achieve source zero energy K-12 school buildings as defined by the U.S. Department of Energy (DOE) zero energy building (ZEB) definition (DOE 2015a). Under this definition, a ZEB is an energy-efficient building in which, on a source energy basis, the actual annual delivered energy is less than or equal to the on-site renewable exported energy.

DOE Zero Energy Ready Home Case Study: TC Legend Homes, Seattle, Washington

Energy Technology Data Exchange (ETDEWEB)

none,

2013-09-01

This house incorporates slab-on-grade, EPS roof, and radiant heating with an air-to-water heat pump that also preheats domestic hot water. Without counting in the solar panels, the home earns a home energy rating system (HERS) score of 37, with projected utility bills of about $740 a year. With the 6.4-kW photovoltaic power system installed on the roof, the home’s HERS scores drops to -1 and utility bills for the all-electric home drop to zero. This home was awarded a 2013 Housing Innovation Award in the affordable builder category.

Thermodynamic analysis of a combined-cycle solar thermal power plant with manganese oxide-based thermochemical energy storage

Science.gov (United States)

Lei, Qi; Bader, Roman; Kreider, Peter; Lovegrove, Keith; Lipiński, Wojciech

2017-11-01

We explore the thermodynamic efficiency of a solar-driven combined cycle power system with manganese oxide-based thermochemical energy storage system. Manganese oxide particles are reduced during the day in an oxygen-lean atmosphere obtained with a fluidized-bed reactor at temperatures in the range of 750-1600°C using concentrated solar energy. Reduced hot particles are stored and re-oxidized during night-time to achieve continuous power plant operation. The steady-state mass and energy conservation equations are solved for all system components to calculate the thermodynamic properties and mass flow rates at all state points in the system, taking into account component irreversibilities. The net power block and overall solar-to-electric energy conversion efficiencies, and the required storage volumes for solids and gases in the storage system are predicted. Preliminary results for a system with 100 MW nominal solar power input at a solar concentration ratio of 3000, designed for constant round-the-clock operation with 8 hours of on-sun and 16 hours of off-sun operation and with manganese oxide particles cycled between 750 and 1600°C yield a net power block efficiency of 60.0% and an overall energy conversion efficiency of 41.3%. Required storage tank sizes for the solids are estimated to be approx. 5-6 times smaller than those of state-of-the-art molten salt systems.

Conversion of zero point energy into high-energy photons

Energy Technology Data Exchange (ETDEWEB)

Ivlev, B. I. [Universidad Autonoma de San Luis Potosi, Instituto de Fisica, Av. Manuel Nava No. 6, Zona Universitaria, 78290 San Luis Potosi, SLP (Mexico)

2016-11-01

An unusual phenomenon, observed in experiments is studied. X-ray laser bursts of keV energy are emitted from a metal where long-living states, resulting in population inversion, are totally unexpected. Anomalous electron-photon states are revealed to be formed inside the metal. These states are associated with narrow, 10{sup -11} cm, potential well created by the local reduction of zero point electromagnetic energy. In contrast to analogous van der Waals potential well, leading to attraction of two hydrogen atoms, the depth of the anomalous well is on the order of 1 MeV. The states in that well are long-living which results in population inversion and subsequent laser generation observed. The X-ray emission, occurring in transitions to lower levels, is due to the conversion of zero point electromagnetic energy. (Author)

Solar energy conversion systems

CERN Document Server

Brownson, Jeffrey R S

2013-01-01

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

Solar energy conversion

Energy Technology Data Exchange (ETDEWEB)

Kistler, J.

1981-08-05

The photovoltaic generator is the central part of all solar systems. Flat solar cells embedded in glass are preferred which can also convert diffuse solar radiation. Hybrid modules generate electrical and thermal energy simultaneously. With decreasing generator cost, the cost of energy storage becomes critical. Development activities are mostly directed on the development of stationary lead accumulator batteries and the electronic charging and protective systems. The block diagram of the current converter is presented, and applications of solar systems in domestic heating engineering, transportation technology, communications, and hydrological engineering. Solar villages are recommended which, established in bilateral cooperation with Third World authorities, may demonstrate the advantages of solar energy in heat and electric power generation.

Technical definition for nearly zero energy buildings nZEB

DEFF Research Database (Denmark)

Kurnitski, Jarek; Allard, Francis; Braham, Derrick

or maximum harmonized requirements as well as details of energy performance calculation framework, it will be up to the Member States 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...

Solar energy system performance evaluation: Seasonal report for IBM System 1B, Carlsbad, New Mexico

Science.gov (United States)

1980-01-01

A hot solar heating and hot water system's operational performance from April 1979 through March 1980 is evaluated. The space heating and hot water loads were near expected values for the year. Solar energy provided 43 percent of the space heating and 53 percent of the hot water energy. The system did not meet the total system solar fraction design value of 69 percent because of a combination of higher estimated space heating load than was actually encountered and the apportioning of solar energy between the space heating and the domestic hot water loads. System losses and high building temperatures also contributed to this deviation. Total net savings were 23.072 million BTUs. Most of the energy savings came during the winter months, but hot water savings were sufficient to justify running the system during the summer months.

Gravity and Zero Point Energy

Science.gov (United States)

Massie, U. W.

When Planck introduced the 1/2 hv term to his 1911 black body equation he showed that there is a residual energy remaining at zero degree K after all thermal energy ceased. Other investigators, including Lamb, Casimir, and Dirac added to this information. Today zero point energy (ZPE) is accepted as an established condition. The purpose of this paper is to demonstrate that the density of the ZPE is given by the gravity constant (G) and the characteristics of its particles are revealed by the cosmic microwave background (CMB). Eddies of ZPE particles created by flow around mass bodies reduce the pressure normal to the eddy flow and are responsible for the force of gravity. Helium atoms resonate with ZPE particles at low temperature to produce superfluid helium. High velocity micro vortices of ZPE particles about a basic particle or particles are responsible for electromagnetic forces. The speed of light is the speed of the wave front in the ZPE and its value is a function of the temperature and density of the ZPE.

Hybrid model predictive control of a residential HVAC system with on-site thermal energy generation and storage

International Nuclear Information System (INIS)

Fiorentini, Massimo; Wall, Josh; Ma, Zhenjun; Braslavsky, Julio H.; Cooper, Paul

2017-01-01

Highlights: • A comprehensive approach to managing thermal energy in residential buildings. • Solar-assisted HVAC system with on-site energy generation and storage. • Mixed logic-dynamical building model identified using experimental data. • Design and implementation of a logic-dynamical model predictive control strategy. • MPC applied to the Net-Zero Energy house winner of the Solar Decathlon China 2013. - Abstract: This paper describes the development, implementation and experimental investigation of a Hybrid Model Predictive Control (HMPC) strategy to control solar-assisted heating, ventilation and air-conditioning (HVAC) systems with on-site thermal energy generation and storage. A comprehensive approach to the thermal energy management of a residential building is presented to optimise the scheduling of the available thermal energy resources to meet a comfort objective. The system has a hybrid nature with both continuous variables and discrete, logic-driven operating modes. The proposed control strategy is organized in two hierarchical levels. At the high-level, an HMPC controller with a 24-h prediction horizon and a 1-h control step is used to select the operating mode of the HVAC system. At the low-level, each operating mode is optimised using a 1-h rolling prediction horizon with a 5-min control step. The proposed control strategy has been practically implemented on the Building Management and Control System (BMCS) of a Net Zero-Energy Solar Decathlon house. This house features a sophisticated HVAC system comprising of an air-based photovoltaic thermal (PVT) collector and a phase change material (PCM) thermal storage integrated with the air-handling unit (AHU) of a ducted reverse-cycle heat pump system. The simulation and experimental results demonstrated the high performance achievable using an HMPC approach to optimising complex multimode HVAC systems in residential buildings, illustrating efficient selection of the appropriate operating modes

Solar energy: Technology and applications

Science.gov (United States)

Williams, J. R.

1974-01-01

It is pointed out that in 1970 the total energy consumed in the U.S. was equal to the energy of sunlight received by only 0.15% of the land area of the continental U.S. The utilization of solar energy might, therefore, provide an approach for solving the energy crisis produced by the consumption of irreplaceable fossil fuels at a steadily increasing rate. Questions regarding the availability of solar energy are discussed along with the design of solar energy collectors and various approaches for heating houses and buildings by utilizing solar radiation. Other subjects considered are related to the heating of water partly or entirely with solar energy, the design of air conditioning systems based on the use of solar energy, electric power generation by a solar thermal and a photovoltaic approach, solar total energy systems, industrial and agricultural applications of solar energy, solar stills, the utilization of ocean thermal power, power systems based on the use of wind, and solar-energy power systems making use of geosynchronous power plants.

Solar energy: a UK assessment

Energy Technology Data Exchange (ETDEWEB)

1976-01-01

A panel convened by UK-ISES to analyze all aspects of solar energy systems and to assess the potential for solar energy utilization and research and development needs in the UK and for export is reported. Topics covered include: solar energy in relation to other energy sources; international solar energy research and development program; the physical nature of solar energy and its availability in the UK and other countries; thermal collection, storage, and low-temperature applications; solar energy and architecture; solar thermal power systems; solar cells; agricultural and biological systems; photochemical systems; social, legal, and political considerations with particular reference to the UK; and future policy on solar research and development for the UK. (WDM)

The Energy Crisis and Solar Energy

Science.gov (United States)

Bockris, J. O'M.

1974-01-01

Examines the status of the energy crisis in Australia. Outlines energy alternatives for the 1990's and describes the present status of solar energy research and the economics of solar energy systems. (GS)

GIS Modeling of Solar Neighborhood Potential at a Fine Spatiotemporal Resolution

Directory of Open Access Journals (Sweden)

Annie Chow

2014-05-01

Full Text Available This research presents a 3D geographic information systems (GIS modeling approach at a fine spatiotemporal resolution to assess solar potential for the development of smart net-zero energy communities. It is important to be able to accurately identify the key areas on the facades and rooftops of buildings that receive maximum solar radiation, in order to prevent losses in solar gain due to obstructions from surrounding buildings and topographic features. A model was created in ArcGIS, in order to efficiently compute and iterate the hourly solar modeling and mapping process over a simulated year. The methodology was tested on a case study area located in southern Ontario, where two different 3D models of the site plan were analyzed. The accuracy of the work depends on the resolution and sky size of the input model. Future work is needed in order to create an efficient iterative function to speed the extraction process of the pixelated solar radiation data.

Comparative evaluation of solar, fission, fusion, and fossil energy resources. Part 1: Solar energy

Science.gov (United States)

Williams, J. R.

1974-01-01

The utilization of solar energy to meet the energy needs of the U.S. is discussed. Topics discussed include: availability of solar energy, solar energy collectors, heating for houses and buildings, solar water heater, electric power generation, and ocean thermal power.

Hydrogen from solar energy

Energy Technology Data Exchange (ETDEWEB)

1977-04-01

The long-range options of energy sources are the breeding reactor, nuclear fusion, and solar energy. Concerning solar energy three systems are being developed: First the photovoltaic cells which are almost ready for industrial production, but which are still too expensive - at least today. Secondly the thermal utilization of solar radiation. Compared to these, thirdly, the photobiological and photochemical possibilities of solar energy utilization have been somewhat neglected so far. However, the photolysis of water by solar energy is a very promising option for future energy demands. This can be done by making use of the photo-synthetic splitting of water in technical facilities or with semiconductors.

Energy and thermodynamic considerations involving electromagnetic zero-point radiation

International Nuclear Information System (INIS)

Cole, Daniel C.

1999-01-01

There has been recent speculation and controversy regarding whether electromagnetic zero-point radiation might be the next candidate in the progression of plentiful energy sources, ranging, for example, from hydrodynamic, chemical, and nuclear energy sources. Certainly, however, extracting energy from the vacuum seems counter intuitive to most people. Here, these ideas are clarified, drawing on simple and common examples. Known properties of electromagnetic zero-point energy are qualitatively discussed. An outlook on the success of utilizing this energy source is then discussed

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.

Solar India - 82: national solar energy convention

Energy Technology Data Exchange (ETDEWEB)

1982-01-01

This document is the proceedings of the Solar India - 82 conference, which was held 17-19 December 1982. The papers are organized into functional groupings which include: (1) solar radiation, (2) flat plate solar collectors and solar water heaters, (3) solar concentrators, (4) solar air heaters and dryers, (5) solar ponds and energy storage, (6) solar cookers, (7) solar stills, (8) selective coatings, (9) photovoltaics, (10) space heating and cooling, (11) bio-energy, and (12) miscellaneous papers. The vast majority of the papers describe work carried out in India, the vast majority of the papers also contain relatively readable abstracts.

Exergy storage to exploit solar energy in air conditioning

Energy Technology Data Exchange (ETDEWEB)

Navarrete-Gonzalez, J.J.; Torres-Reyes, E. [Guanajuato Univ., Guanajuato (Mexico). Inst. de Investigaciones Cientificas; Cervantes-de Gortari, J.G. [Univ. of Cuidad, Mexico City (Mexico). Dept. de Termoenergia y Mejoramiento Ambiental

2006-07-01

A thermodynamic procedure was developed to analyze the exergy of a rock bed thermal storage unit that used solar power to acclimatize a pig farm. Thermal behaviour was described by means of a control volume that included the entire system and assumed a unidirectional air flow and an adiabatic process. The thermodynamic properties of the system were determined as a function of the experimental temperature profiles developed during thermal storage from solar to thermal energy conversion provided by a solar collector at a fixed mass rate of air flow. Experimental data were used to calculate the energy yield and to determine the entropy generation inside the system. The aim of the study was to determine how well the thermodynamic model matched the real data obtained experimentally during normal operating conditions. Results indicated that an exergy accumulation existed inside the control volume, which was the net result of the energy gain during the heating process. However, entropy generation due to irreversibilities was studied for just 1 air flow. Further research is needed to establish a semi-empirical model of the process with the minimum of entropy generation. It was concluded that the thermal energy storage system was suitable for use in pig farms. 5 refs., 8 figs.

Solar energy: photovoltaics

International Nuclear Information System (INIS)

Goetzberger, A.; Voss, B.; Knobloch, J.

1994-01-01

This textbooks covers the following topics: foundations of photovoltaics, solar energy, P-N junctions, physics of solar cells, high-efficiency solar cells, technology of Si solar cells, other solar cells, photovoltaic applications. (orig.)

Urban net-zero water treatment and mineralization: experiments, modeling and design.

Science.gov (United States)

Englehardt, James D; Wu, Tingting; Tchobanoglous, George

2013-09-01

Water and wastewater treatment and conveyance account for approximately 4% of US electric consumption, with 80% used for conveyance. Net zero water (NZW) buildings would alleviate demands for a portion of this energy, for water, and for the treatment of drinking water for pesticides and toxic chemical releases in source water. However, domestic wastewater contains nitrogen loads much greater than urban/suburban ecosystems can typically absorb. The purpose of this work was to identify a first design of a denitrifying urban NZW treatment process, operating at ambient temperature and pressure and circum-neutral pH, and providing mineralization of pharmaceuticals (not easily regulated in terms of environmental half-life), based on laboratory tests and mass balance and kinetic modeling. The proposed treatment process is comprised of membrane bioreactor, iron-mediated aeration (IMA, reported previously), vacuum ultrafiltration, and peroxone advanced oxidation, with minor rainwater make-up and H2O2 disinfection residual. Similar to biological systems, minerals accumulate subject to precipitative removal by IMA, salt-free treatment, and minor dilution. Based on laboratory and modeling results, the system can produce potable water with moderate mineral content from commingled domestic wastewater and 10-20% rainwater make-up, under ambient conditions at individual buildings, while denitrifying and reducing chemical oxygen demand to below detection (<3 mg/L). While economics appear competitive, further development and study of steady-state concentrations and sludge management options are needed. Copyright © 2013 Elsevier Ltd. All rights reserved.

Zero Energy Building definition–a literature review

DEFF Research Database (Denmark)

Heiselberg, Per Kvols; Marszal, Anna Joanna

2011-01-01

The worldwide CO2 emission mitigation efforts, the growing energy resource shortage and the fact that buildings are responsible for a large share of the world’s primary energy use drives research towards new building concepts, in particular Zero Energy/Emission Buildings (ZEBs). Unfortunately, th...

Solar energy. Usage of the solar energy in other forms of energy

International Nuclear Information System (INIS)

Gruevski, Trpe

2004-01-01

Solar energy, which was a utopian dream forty years ago, is today already on the market, particularly for specialized uses and in remote areas. After a brief description of the solar energy usage, the theory, technology and applications of photovoltaic cells are presented

Thermodynamic analysis of a combined-cycle solar thermal power plant with manganese oxide-based thermochemical energy storage

Directory of Open Access Journals (Sweden)

Lei Qi

2017-01-01

Full Text Available We explore the thermodynamic efficiency of a solar-driven combined cycle power system with manganese oxide-based thermochemical energy storage system. Manganese oxide particles are reduced during the day in an oxygen-lean atmosphere obtained with a fluidized-bed reactor at temperatures in the range of 750–1600°C using concentrated solar energy. Reduced hot particles are stored and re-oxidized during night-time to achieve continuous power plant operation. The steady-state mass and energy conservation equations are solved for all system components to calculate the thermodynamic properties and mass flow rates at all state points in the system, taking into account component irreversibilities. The net power block and overall solar-to-electric energy conversion efficiencies, and the required storage volumes for solids and gases in the storage system are predicted. Preliminary results for a system with 100 MW nominal solar power input at a solar concentration ratio of 3000, designed for constant round-the-clock operation with 8 hours of on-sun and 16 hours of off-sun operation and with manganese oxide particles cycled between 750 and 1600°C yield a net power block efficiency of 60.0% and an overall energy conversion efficiency of 41.3%. Required storage tank sizes for the solids are estimated to be approx. 5–6 times smaller than those of state-of-the-art molten salt systems.

Alternatives in solar energy

Science.gov (United States)

Schueler, D. G.

1978-01-01

Although solar energy has the potential of providing a significant source of clean and renewable energy for a variety of applications, it is expected to penetrate the nation's energy economy very slowly. The alternative solar energy technologies which employ direct collection and conversion of solar radiation as briefly described.

Solar Renewable Energy. Teaching Unit.

Science.gov (United States)

Buchanan, Marion; And Others

This unit develops the concept of solar energy as a renewable resource. It includes: (1) an introductory section (developing understandings of photosynthesis and impact of solar energy); (2) information on solar energy use (including applications and geographic limitations of solar energy use); and (3) future considerations of solar energy…

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.

U.S. Department of Energy Zero Energy Ready Home Implementation

Energy Technology Data Exchange (ETDEWEB)

VonThoma, E. [Univ. of Minnesota, St. Paul, MN (United States). NorthernSTAR Building America Partnership; Mosiman, G. [Univ. of Minnesota, St. Paul, MN (United States). NorthernSTAR Building America Partnership

2017-07-01

This report documents the process and outcomes involved in achieving the U.S. Department of Energy Zero Energy Ready Home (ZERH) program certification standards while helping homebuilders in Climate Zones 5 and 6 in the Upper Midwest achieve ZERH certification.

Research progress about chemical energy storage of solar energy

Science.gov (United States)

Wu, Haifeng; Xie, Gengxin; Jie, Zheng; Hui, Xiong; Yang, Duan; Du, Chaojun

2018-01-01

In recent years, the application of solar energy has been shown obvious advantages. Solar energy is being discontinuity and inhomogeneity, so energy storage technology becomes the key to the popularization and utilization of solar energy. Chemical storage is the most efficient way to store and transport solar energy. In the first and the second section of this paper, we discuss two aspects about the solar energy collector / reactor, and solar energy storage technology by hydrogen production, respectively. The third section describes the basic application of solar energy storage system, and proposes an association system by combining solar energy storage and power equipment. The fourth section briefly describes several research directions which need to be strengthened.

Solar energy system performance evaluation: Seasonal report for Elcam Tempe Arizona State University, Tempe, Arizona

Science.gov (United States)

1980-01-01

The solar system, Elcam-Tempe, was designed by Elcam Incorporated, Santa Barbara, California, to supply commercial domestic hot water heating systems to the Agriculture Department residence at Arizona State University. The building is a single story residence located at the agriculture experiment farm of the Arizona State University. The energy system's four modes of operation are described. Electrical energy savings at the site was a net of 5.54 million Btu after the 0.17 million Btu of operating energy required to operate collector loop circulating pump were subtracted. The energy savings due to solar was less than the system's potential. On an average, twice as much hot water could have been used with significant solar energy contribution. The system corrosion and deposits caused by using dissimilar metals in the collector loop was the only problem noted with the Elcam-Tempe system.

The impact of the year-on-year variation in the intensity of solar radiation on the energy intensity of low-energy and passive houses

Directory of Open Access Journals (Sweden)

Šubrt Roman

2017-01-01

Full Text Available Solar radiation is a significant segment of heat gains in the operation of buildings. The importance of this segment is highlighted by lowering the energy performance of buildings. The current condition of assessment considers the standard values of solar radiation but these are often very different from the fair values. In the contribution it draws attention to not only to on-year variation in solar fluctuations in the intensity of solar radiation and its significant long-term deviation from the standard values but also to the impact to energy building in reliance to its energy intensity. The attention will be focused also to different values in standards valid in the Czech Republic. This specification of energy assessment of buildings is not only necessary to approximate calculations of real state, but mainly because we can expect more disputes about if a building has declared calculating the parameters of a building with nearly zero-energy or passive house.

Thermodynamic evaluation of a novel solar-biomass hybrid power generation system

International Nuclear Information System (INIS)

Bai, Zhang; Liu, Qibin; Lei, Jing; Wang, Xiaohe; Sun, Jie; Jin, Hongguang

2017-01-01

Highlights: • A solar-biomass hybrid power system with zero carbon dioxide emission is proposed. • The internal mechanisms of the solar-biomass utilization are discussed. • The on-design and off-design properties of the system are numerically investigated. • The configurations of the proposed system are optimized. - Abstract: A solar-biomass hybrid power generation system, which integrates a solar thermal energy collection subsystem, a biomass steam boiler and a steam turbine power generation block, is developed for efficiently utilizing renewable energies. The solar thermal energy is concentrated by parabolic trough collectors and is used to heat the feed-water to the superheated steam of 371 °C, then the generated solar steam is further heated to a higher temperature level of 540 °C via a second-stage heating process in a biomass boiler, the system power generation capacity is about 50 MW. The hybrid process of the solar energy and biomass contributes to ameliorating the system thermodynamic performances and reducing of the exergy loss within the steam generation process. The off-design evaluation results indicate that the annual net solar-to-electric efficiency of the hybrid power system is improved to 18.13%, which is higher than that of the typical parabolic trough solar power system as 15.79%. The levelized cost of energy drops to 0.077 $/(kW h) from 0.192 $/(kW h). The annual biomass consumption rate is reduced by 22.53% in comparison with typical biomass power systems. The research findings provide a promising approach for the efficient utilization of the abundant renewable energies resources and the reduction of carbon dioxide emission.

Solar energy perspectives in France

International Nuclear Information System (INIS)

2008-01-01

In a context combining climate change, energy supply crisis, an increased interest in solar energy, a strongly increasing market of solar installations, new technologies, a promotion of the development of the use solar energy in France and a fast development of the water heater and photovoltaic generator markets in France, this report proposes a wide overview of the past, present and future development of solar energy. It discusses the evolution of the French national energy policy and of the solar energy within this policy. It presents and discusses the solar energy resources, their strengths and weaknesses, their geographical and time distribution. It describes the various uses and applications of solar energy in buildings, discusses different aspects of this market (actors, economical data, evolutions, public incentives, perspectives). Then, it describes and discusses technical and economical aspects of two important technologies, the photovoltaic solar energy and the thermodynamic conversion of solar energy. Public incentives, laws and regulations, technical and economic aspects of the connection to the distribution network are then discussed. Some recommendations and ideas are formulated concerning research activities, industrial development, quality of equipment and facilities, personnel education, investment needs

Rev-Changes in Primary Energy Use and CO2 Emissions—An Impact Assessment for a Building with Focus on the Swedish Proposal for Nearly Zero Energy Buildings

Directory of Open Access Journals (Sweden)

Mattias Gustafsson

2017-07-01

Full Text Available In the European Union’s Energy Performance of Buildings Directive, the energy efficiency goal for buildings is set in terms of primary energy use. In the proposal from the National Board of Housing, Building, and Planning, for nearly zero energy buildings in Sweden, the use of primary energy is expressed as a primary energy number calculated with given primary energy factors. In this article, a multi-dwelling building is simulated and the difference in the primary energy number is investigated when the building uses heat from district heating systems or from heat pumps, alone or combined with solar thermal or solar photovoltaic systems. It is also investigated how the global CO2 emissions are influenced by the different energy system combinations and with different fuels used. It is concluded that the calculated primary energy number is lower for heat pump systems, but the global CO2 emissions are lowest when district heating uses mostly biofuels and is combined with solar PV systems. The difference is up to 140 tonnes/year. If the aim with the Swedish building code is to decrease the global CO2 emissions then the ratio between the primary energy factors for electricity and heat should be larger than three and considerably higher than today.

Solar energy in Israel

International Nuclear Information System (INIS)

Zvirin, Y.; Zamkow, S.

1993-01-01

The state of Israel has been a pioneer in the solar energy development and utilization since it was founded. In the 50's solar domestic home heaters became commercially available. At the same time research work has been started in different areas of solar energy, which led to more advanced solar systems for additional applications. The presentation includes some details of commercial utilization of solar energy and a brief description of the main Research and Development projects in industry, universities and research institutes. (authors)

Efficiency limit of solar cells with index-near-zero photon management layers

Energy Technology Data Exchange (ETDEWEB)

Kirk, A.P.

2017-05-15

As single-junction solar cells saturate in efficiency, the topic of photon management has generated interest in the long running quest to exceed the Shockley-Queisser efficiency limit. While a mirror applied to the backside of a solar cell has proven its benefit as a photon management layer in record setting devices that fall within the Shockley-Queisser limit, it has been proposed that a new type of photon management layer – a transparent index-near-zero (INZ) material – applied to the top surface of a solar cell will allow it to finally exceed the Shockley-Queisser limit. INZ layers – and their influence on solar cell current density, open circuit voltage, and power conversion efficiency – are analyzed. By considering the principle of detailed balance, Snell's law, and the role that entropy plays, it is shown that INZ layers do not allow a solar cell to exceed the Shockley-Queisser efficiency limit. At best, a solar cell with an INZ layer would have the same Shockley-Queisser limiting efficiency as a conventional solar cell tracked under a direct solar spectrum (direct beam radiation only), yet would suffer diminished efficiency under a global solar spectrum (direct beam plus diffuse light) due to the presence of an external critical acceptance angle.

Efficiency limit of solar cells with index-near-zero photon management layers

International Nuclear Information System (INIS)

Kirk, A.P.

2017-01-01

As single-junction solar cells saturate in efficiency, the topic of photon management has generated interest in the long running quest to exceed the Shockley-Queisser efficiency limit. While a mirror applied to the backside of a solar cell has proven its benefit as a photon management layer in record setting devices that fall within the Shockley-Queisser limit, it has been proposed that a new type of photon management layer – a transparent index-near-zero (INZ) material – applied to the top surface of a solar cell will allow it to finally exceed the Shockley-Queisser limit. INZ layers – and their influence on solar cell current density, open circuit voltage, and power conversion efficiency – are analyzed. By considering the principle of detailed balance, Snell's law, and the role that entropy plays, it is shown that INZ layers do not allow a solar cell to exceed the Shockley-Queisser efficiency limit. At best, a solar cell with an INZ layer would have the same Shockley-Queisser limiting efficiency as a conventional solar cell tracked under a direct solar spectrum (direct beam radiation only), yet would suffer diminished efficiency under a global solar spectrum (direct beam plus diffuse light) due to the presence of an external critical acceptance angle.

Efficiency limit of solar cells with index-near-zero photon management layers

Science.gov (United States)

Kirk, A. P.

2017-05-01

As single-junction solar cells saturate in efficiency, the topic of photon management has generated interest in the long running quest to exceed the Shockley-Queisser efficiency limit. While a mirror applied to the backside of a solar cell has proven its benefit as a photon management layer in record setting devices that fall within the Shockley-Queisser limit, it has been proposed that a new type of photon management layer - a transparent index-near-zero (INZ) material - applied to the top surface of a solar cell will allow it to finally exceed the Shockley-Queisser limit. INZ layers - and their influence on solar cell current density, open circuit voltage, and power conversion efficiency - are analyzed. By considering the principle of detailed balance, Snell's law, and the role that entropy plays, it is shown that INZ layers do not allow a solar cell to exceed the Shockley-Queisser efficiency limit. At best, a solar cell with an INZ layer would have the same Shockley-Queisser limiting efficiency as a conventional solar cell tracked under a direct solar spectrum (direct beam radiation only), yet would suffer diminished efficiency under a global solar spectrum (direct beam plus diffuse light) due to the presence of an external critical acceptance angle.

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

Zero Energy Buildings – Design Principles and Built Examples

DEFF Research Database (Denmark)

Bejder, Anne Kirkegaard; Knudstrup, Mary-Ann; Jensen, Rasmus Lund

Designing a zero energy building is a complicated task, and in order to achieve good results it is necessary to include knowledge from a range of sources. Therefore, cooperation is required between different professions and between generalists and specialists from the very beginning of the process...... for the development of zero energy houses. These strategies and technologies are illustrated through simple design principles and built examples • identify technical and architectural potentials and challenges related to design strategies of crucial importance to the development of zero energy houses • identify...... technical and architectural potentials and challenges related to the application of new technologies • make visible engineering and architectural issues and create greater transparency, providing a point of departure for cross-disciplinary cooperation....

Net metering in British Columbia : white paper

International Nuclear Information System (INIS)

Berry, T.

2003-01-01

Net metering was described as being the reverse registration of an electricity customer's revenue meter when interconnected with a utility's grid. It is a provincial policy designed to encourage small-distributed renewable power generation such as micro-hydro, solar energy, fuel cells, and larger-scale wind energy. It was noted that interconnection standards for small generation is an important issue that must be addressed. The British Columbia Utilities Commission has asked BC Hydro to prepare a report on the merits of net metering in order to support consultations on a potential net metering tariff application by the utility. This report provides information on net metering with reference to experience in other jurisdictions with net metering, and the possible costs and benefits associated with net metering from both a utility and consumer perspective. Some of the barriers and policy considerations for successful implementation of net metering were also discussed. refs., tabs., figs

Zero energy reactor 'RB'

Energy Technology Data Exchange (ETDEWEB)

Popovic, D; Takac, S; Markovic, H; Raisic, N; Zdravkovic, Z; Radanovic, Lj [Boris Kidric Institute of Nuclear Sciences, Vinca, Beograd (Yugoslavia)

1959-03-15

In 1958 the zero energy reactor RB was built with the purpose of enabling critical experiments with various reactor systems to be carried out. The first core assembly built in this reactor consists of heavy water as moderator and natural uranium metal as fuel. In order to be able to obtain very accurate results when measuring the main characteristics of the assembly the reactor was built as a completely bare system. (author)

Solar Energy Perspectives In Egypt

International Nuclear Information System (INIS)

Comsan, M.N.H.

2010-01-01

Egypt belongs to the global sun-belt. The country is in advantageous position with solar energy. In 1991 solar atlas for Egypt was issued indicating that the country enjoys 2900-3200 hours of sunshine annually with annual direct normal energy density 1970-3200 kWh/m2 and technical solar-thermal electricity generating potential of 73.6 Peta watt hour (PWh). Egypt was among the first countries to utilize solar energy. In 1910, a practical industrial scale solar system engine was built at Maadi south to Cairo using solar thermal parabolic collectors. The engine was used to produce steam which drove a series of large water pumps for irrigation. Nowadays utilization of solar energy includes use of photovoltaic cells, solar water heating and solar thermal power. Use of solar thermal technology may include both electricity generation and water desalination, which is advantageous for Egypt taking in consideration its shortage in water supply. The article discusses perspectives of solar energy in Egypt and developmental trends till 2050

Mini-Split Heat Pump Evaluation and Zero Energy Ready Home Support

Energy Technology Data Exchange (ETDEWEB)

Herk, Anastasia [IBACOS, Inc., Pittsburgh, PA (United States)

2017-01-01

IBACOS worked with builder Imagine Homes to evaluate the performance of an occupied new construction test house following construction of the house in the hot, humid climate of San Antonio, Texas. The project measures the effectiveness of a space conditioning strategy using a multihead mini-split heat pump (MSHP) system in a reduced-load home to achieve acceptable comfort levels (temperature and humidity) and energy performance. IBACOS collected long-term data and analyzed the energy consumption and comfort conditions of the occupied house after one year of operation. Although measured results indicate that the test system provides comfort both inside and outside the ASHRAE Standard 55-2010 range, the occupants of the house claimed both adequate comfort and appreciation of the ease of use and flexibility of the installed MSHP system. IBACOS also assisted the builder to evaluate design and specification changes necessary to comply with Zero Energy Ready Home, but the builder chose to not move forward with it because of concerns about the 'solar ready' requirements of the program.

Weather-power station. Solar energy, wind energy, water energy

Energy Technology Data Exchange (ETDEWEB)

Schatta, M

1975-10-02

A combined power station is described, which enables one to convert solar energy and wind energy into other forms of energy. The plant consists of a water-filled boiler, in which solar energy heats the water by concentration, solar cells, and finally wind rotors, which transform wind energy into electrical energy. The transformed energy is partly available as steam heat, partly as mechanical or electrical energy. The plant can be used for supplying heating systems or electrolysis equipment. Finally, by incorporating suitable motors, a mobile version of the system can be produced.

Community-Wide Zero Energy Ready Home Standard

Energy Technology Data Exchange (ETDEWEB)

Herk, A. [IBACOS, Inc., Pittsburght, PA (United States); Beggs, T. [IBACOS, Inc., Pittsburght, PA (United States)

2016-02-05

This report outlines the steps a developer can use when looking to create and implement higher performance standards such as the U.S. Department of Energy (DOE) Zero Energy Ready Home (ZERH) standards in a community. The report also describes the specific examples of how this process was followed by a developer, Forest City, in the Stapleton community in Denver, Colorado. IBACOS described the steps used to begin to bring the DOE ZERH standard to the Forest City Stapleton community based on 15 years of community-scale development work done by IBACOS. As a result of this prior IBACOS work, the team gained an understanding of the various components that a master developer needs to consider and created strategies for incorporating those components in the initial phases of development to achieve higher performance buildings in the community. An automated scoring system can be used to perform an internal audit that provides a detailed and consistent evaluation of how several homes under construction or builders' floor plans compare with the requirements of the DOE Zero Energy Ready Home program. This audit can be performed multiple times at specific milestones during construction to allow the builder to make changes as needed throughout construction for the project to meet Zero Energy Ready Home standards. This scoring system also can be used to analyze a builder's current construction practices and design.

Evaluation of a hybrid system for a nearly zero energy greenhouse

International Nuclear Information System (INIS)

Yildirim, Nurdan; Bilir, Levent

2017-01-01

Highlights: • A nearly zero energy greenhouse concept was foreseen for three products. • A hybrid system with photovoltaics and a ground source heat pump was evaluated. • Annual photovoltaics electricity generation was found as 21510.4 kWh. • Yearly coverage ratio values were determined between 86.8% and 104.5%. • Economic and environmental analyses were also conducted. - Abstract: Greenhouses are widely used in the World, especially in the Mediterranean climate, to provide suitable environment in cultivation of different agricultural crops. Significant amount of energy is necessary to produce, process and distribute these crops. Various systems, including steam or hot water radiation system and hot air heater system, are being used in greenhouse heating. A ground source heat pump system, generally seen as a favorable option since it can provide both heating and cooling energy, is considered for a greenhouse in this study. The aim of this study is to evaluate a renewable energy option for the required total energy need of a greenhouse. Grid connected solar photovoltaic panels are selected to assist a ground source heat pump, and generate sufficient electrical energy for lighting. In this way, a nearly zero energy greenhouse concept is foreseen for three different agricultural products. Monthly and annual heating, cooling and lighting energy load of the greenhouse for these agricultural products were computed. The monthly average electricity generation of 66 photovoltaic panels, which cover 50% of the southern face part of the asymmetric roof, was calculated. Annual photovoltaic electricity generation was found as 21510.4 kWh. It was observed that photovoltaic electricity generation can meet 33.2–67.2% of greenhouse demand in summer operation months. Nevertheless, the coverage ratio, calculated by dividing the photovoltaic panels electricity generation to the electricity demand of the greenhouse (heating, cooling and lighting) for each crop, were very

The economic effect of electricity net-metering with solar PV: Consequences for network cost recovery, cross subsidies and policy objectives

International Nuclear Information System (INIS)

Eid, Cherrelle; Reneses Guillén, Javier; Frías Marín, Pablo; Hakvoort, Rudi

2014-01-01

Net-metering is commonly known as a practice by which owners of distributed generation (DG) units may offset their electricity consumption from the grid with local generation. The increasing number of prosumers (consumers that both produce and consume electricity) with solar photovoltaic (PV) generation combined with net-metering results in reduced incomes for many network utilities worldwide. Consequently, this pushes utilities to increase charges per kW h in order to recover costs. For non-PV owners, this could result into inequality issues due to the fact that also non-PV owners have to pay higher chargers for their electricity consumed to make up for netted costs of PV-owners. In order to provide insight in those inequality issues caused by net-metering, this study presents the effects on cross-subsidies, cost recovery and policy objectives evolving from different applied netmetering and tariff designs for a residential consumer. Eventually this paper provides recommendations regarding tariffs and metering that will result in more explicit incentives for PV, instead of the current implicit incentives which are present to PV owners due to net-metering. - Highlights: • Network users are frequently charged by energy charging and fixed charging. • Net-metering with energy charging causes potential problems for DSO cost recovery. • Increasing rolling credit timeframes amplify net-metering impacts on cost recovery. • Observed capacity charging can incentivize local storage and self-consumption. • PV owners should receive direct incentives in order to avoid cross subsidization

Public Policies of Solar Energy

International Nuclear Information System (INIS)

Bouvier, Yves; Pehlivanian, Sophie; Teissier, Pierre; Chauvin-Michel, Marion; Forget, Marie; Raymond, Roland; Hyun Jin Yu, Julie; Popiolek, Nathalie; Guthleben, Denis

2013-01-01

This dossier about the Public Policies of Solar Energy brings together the presentations given in June 2013 at a colloquium organised by the Savoie university of Chambery (France): Introduction (Yves Bouvier, Sophie Pehlivanian); Passive solar energy in the shade of the French energy policy, 1945-1986 (Pierre Teissier); Solar architectures and energy policies in France: from oil crisis to solar crisis (Marion Chauvin-Michel); Sun in media, between promotion and contestation (Sophie Pehlivanian); Public policies of solar energy and territorial jurisdictions: the example of village photovoltaic power plants (Marie Forget); Energy social system and ordinary creative movement (Roland Raymond); The Historical Evolution of South Korea's Solar PV Policies since the 1970's (Julie Hyun Jin Yu, Nathalie Popiolek); Research on solar energy from yesterday to the present day: an historical project (Denis Guthleben); Photovoltaic power: public policies and economical consequences. The French choices in the international context - 1973-2013 (Alain Ricaud)

Zero Energy Buildings – Design Principles and Built Examples

DEFF Research Database (Denmark)

Designing a zero energy building is a complicated task, and in order to achieve good results it is necessary to include knowledge from a range of sources. Therefore, cooperation is required between different professions and between generalists and specialists from the very beginning of the process...... knowledge must be acquired, depending on the project in question. Through a cross-disciplinary approach to architecture and building design, and based on an integrated design process, this publication will: • introduce a number of design strategies and technologies which are particularly important...... for the development of zero energy houses. These strategies and technologies are illustrated through simple design principles and built examples • identify technical and architectural potentials and challenges related to design strategies of crucial importance to the development of zero energy houses • identify...

Next Steps on the Road to Zero Energy Buildings: Report on October 23-24, 2000 Meeting Held at the National Renewable Energy Laboratory, Golden, Colorado

Energy Technology Data Exchange (ETDEWEB)

Comer, Jerry [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2000-11-01

This report summarizes a 2-day meeting held October 23-24, 2000 at the National Renewable Energy Laboratory in Golden, Colorado. Approximately 60 individuals attended the meeting from the following segments: building industry; solar thermal manufacturers (solar hot water, SHW); photovoltaic manufacturers (PV); generalists (consultants and interested parties involved in renewable energy); National Renewable Energy Laboratory (NREL) and Sandia National Laboratory (SNL); and US Department of Energy. The objectives of the meeting included: acquaint attendees with the Zero Energy Buildings (ZEB) goal; determine the most cost effective methods of incorporating solar technologies in production-built homes; identify 'make or break' areas to focus on; outline 6 month, 1 year, 5 year strategies and tactics; and create action plan with designated responsibilities. The format of the meeting was designed to maximize interaction between all attendees and to create a 'working' environment where a roadmap and action plans to support ZEB efforts would be created. Presentations the morning of the first day set the context for the discussions and breakout sessions that followed. The agenda was modified at the end of the first day of meetings to reflect the input of attendees. The revised agenda is included in the Appendix.

Solar energy emplacement developer

Science.gov (United States)

Mortensen, Michael; Sauls, Bob

1991-01-01

A preliminary design was developed for a Lunar Power System (LPS) composed of photovoltaic arrays and microwave reflectors fabricated from lunar materials. The LPS will collect solar energy on the surface of the Moon, transform it into microwave energy, and beam it back to Earth where it will be converted into usable energy. The Solar Energy Emplacement Developer (SEED) proposed will use a similar sort of solar energy collection and dispersement to power the systems that will construct the LPS.

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.

Streamline, Organizational, Legislative and Administrative Response to Permitting, PV Market Share, and Solar Energy Costs (Broward Go SOLAR)

Energy Technology Data Exchange (ETDEWEB)

Halsey, Jeffery D. [Broward County, Fort Lauderdale, FL (United States)

2013-08-28

Broward County and its partners (the Go SOLAR Team), operating under a Department of Energy Rooftop Solar Challenge Agreement, designed, developed and implemented an online permitting system for rooftop solar PV systems. This is a single web based system with a single permit fee that will issue a permit, with a set of design plans preapproved by partner building officials, within one hour. The system is currently available at gosolar.broward.org for use within any of the partner Authorities Having [permitting] Jurisdiction (AHJ). Additionally, the Go SOLAR Team researched, developed and to the extent feasible, implemented three best management practices to make a fertile environment for the new online permit system. These included Net Metering and Interconnection Standards, Solar-Friendly Financing, and Planning and Zoning Ordinances. Finally, the team implemented a substantial outreach effort to advocate for the development of solar in Broward County, with an emphasis on Solar Rights, concluding with a Go SOLAR Fest day and a half conference with over 1,200 attendees and 50 exhibitors. The Go SOLAR project was completed on time, under DOE’s budgeted amount, and all project objectives were met or exceeded.

Bright Idea: Solar Energy Primer.

Science.gov (United States)

Missouri State Dept. of Natural Resources, Jefferson City.

This booklet is intended to address questions most frequently asked about solar energy. It provides basic information and a starting point for prospective solar energy users. Information includes discussion of solar space heating, solar water heating, and solar greenhouses. (Author/RE)

Solar Thermal Energy; Energia Solar Termica

Energy Technology Data Exchange (ETDEWEB)

Perez-Martinez, M; Cuesta-Santianes, M J; Cabrera Jimenez, J A

2008-07-01

Approximately, 50 % of worldwide primary energy consumption is done in the form of heat in applications with a temperature lower than 250 degree centigree (low-medium temperature heat). These data clearly demonstrate the great potential of solar thermal energy to substitute conventional fossil fuels, which are becoming more expensive and are responsible for global warming. Low-medium temperature solar thermal energy is mainly used to obtain domestic hot water and provide space heating. Active solar thermal systems are those related to the use of solar thermal collectors. This study is dealing with low temperature solar thermal applications, mainly focusing on active solar thermal systems. This kind of systems has been extensively growing worldwide during the last years. At the end of 2006, the collector capacity in operation worldwide equalled 127.8 GWth. The technology is considered to be already developed and actions should be aimed at favouring a greater market penetration: diffusion, financial support, regulations establishment, etc. China and USA are the leading countries with a technology based on evacuated tube collectors and unglazed collectors, respectively. The rest of the world markets are dominated by the flat glazed collectors technology. (Author) 15 refs.

Solar energy in buildings: Implications for California energy policy

Science.gov (United States)

Hirshberg, A. S.; Davis, E. S.

1977-01-01

An assessment of the potential of active solar energy systems for buildings in California is summarized. The technology used for solar heating, cooling, and water heating in buildings is discussed. The major California weather zones and the solar energy designs are described, as well as the sizing of solar energy systems and their performance. The cost of solar energy systems is given both at current prices and at prices consistent with optimistic estimates for the cost of collectors. The main institutional barriers to the wide spread use of solar energy are summarized.

Solar Energy Evolution and Diffusion Studies Webinars | Solar Research |

Science.gov (United States)

NREL Studies Webinars Solar Energy Evolution and Diffusion Studies Webinars These webinars . Department of Energy's Solar Energy Evolution and Diffusion Studies (SEEDS) program. SEEDS 2017-2019 Study Residential Solar July 20, 2017 Presenters: Kiran Lakkaraju, Sandia National Laboratories Yevgeniy Vorobeychik

Control of Solar Energy Systems

CERN Document Server

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

2012-01-01

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

Zero Energy Ready Home Multifamily Case Study Analysis

Energy Technology Data Exchange (ETDEWEB)

Dentz, Jordan [Advanced Residential Integrated Energy Solutions Collaborative, New York, NY (United States); Alaigh, Kunal [Advanced Residential Integrated Energy Solutions Collaborative, New York, NY (United States)

2016-02-01

Two multifamily buildings planned in Climate Zone 4 were analyzed to determine the cost, energy and performance implications of redesigning them to comply with Zero Energy Ready Home, a recognition program of the U.S. Department of Energy. Energy modeling was conducted on one representative apartment in each building using BEopt.

A novel polygeneration system integrating photovoltaic/thermal collectors, solar assisted heat pump, adsorption chiller and electrical energy storage: Dynamic and energy-economic analysis

International Nuclear Information System (INIS)

Calise, Francesco; Figaj, Rafal Damian; Vanoli, Laura

2017-01-01

Highlights: • Space heating/cooling, domestic hot water and electrical energy are provided by the system. • Two different users are investigated: fitness center and office. • The influence of the battery system on system economic performance is scarce. • Net metering contract is more profitable compared to simplified purchase/resale arrangement one. - Abstract: In this paper a dynamic simulation model and a thermo-economic analysis of a novel polygeneration system are presented. The system includes photovoltaic/thermal collectors coupled with a solar-assisted heat pump, an adsorption chiller and an electrical energy storage. The modelled plant supplies electrical energy, space heating and cooling and domestic hot water. The produced solar thermal energy is used during the winter to supply the heat pump evaporator, providing the required space heating. In summer, solar thermal energy is used to drive an adsorption chiller providing the required space cooling. All year long, solar thermal energy in excess, with respect to the space heating and cooling demand, is used to produce domestic hot water. The produced electrical energy is self-consumed by both user and system auxiliary equipment and/or supplied to the grid. The system model includes a detailed electrical energy model for user storage and exchange with the grid along with a detailed building model. This study is a continuation of previous works recently presented by the authors. In particular, the present paper focuses on the real electrical demands of several types of users and on the analysis of the comfort of building users. Differently from the works previously published by the authors, the present work bases the calculations on measured electrical demands of real users (fitness center and offices). The system performance is analyzed with two different electricity supply contracts: net metering and simplified purchase/resale arrangement. Daily, weekly and yearly results are presented. Finally, a

Poster abstract: A decentralized routing scheme based on a zero-sum game to optimize energy in solar powered sensor networks

KAUST Repository

Dehwah, Ahmad H.; Tembine, Hamidou; Claudel, Christian G.

2014-01-01

This poster is aimed at solving the problem of maximizing the energy margin of a solar-powered sensor network at a fixed time horizon, to maximize the network performance during an event to monitor. Using a game theoretic approach, the optimal routing maximizing the energy margin of the network at a given time under solar power forcing can be computed in a decentralized way and solved exactly through dynamic programming with a low overall complexity. We also show that this decentralized algorithm is simple enough to be implemented on practical sensor nodes. Such an algorithm would be very useful whenever the energy margin of a solar-powered sensor network has to be maximized at a specific time. © 2014 IEEE.

Poster abstract: A decentralized routing scheme based on a zero-sum game to optimize energy in solar powered sensor networks

KAUST Repository

Dehwah, Ahmad H.

2014-04-01

This poster is aimed at solving the problem of maximizing the energy margin of a solar-powered sensor network at a fixed time horizon, to maximize the network performance during an event to monitor. Using a game theoretic approach, the optimal routing maximizing the energy margin of the network at a given time under solar power forcing can be computed in a decentralized way and solved exactly through dynamic programming with a low overall complexity. We also show that this decentralized algorithm is simple enough to be implemented on practical sensor nodes. Such an algorithm would be very useful whenever the energy margin of a solar-powered sensor network has to be maximized at a specific time. © 2014 IEEE.

Photon management with index-near-zero materials

Energy Technology Data Exchange (ETDEWEB)

Wang, Zhu; Yu, Zongfu [Department of Electrical and Computer Engineering, University of Wisconsin Madison, Madison, Wisconsin 53706 (United States); Wang, Ziyu [Department of Foundation, Southeast University, Chengxian College, 210018 Nanjing (China)

2016-08-01

Index-near-zero materials can be used for effective photon management. They help to restrict the angle of acceptance, resulting in greatly enhanced light trapping limit. In addition, these materials also decrease the radiative recombination, leading to enhanced open circuit voltage and energy efficiency in direct bandgap solar cells.

Solar energy in Peru

Energy Technology Data Exchange (ETDEWEB)

Pierson, H.

1981-12-01

The past, present, and future of Peru is discussed in terms of solar energy development and the social, economic, climatic, and technical factors involved. It is pointed out that there are 3 geographical divisions in Peru including: (1) the foggy coastal strip where rain is infrequent, insolation is low and population is high; (2) the mountainous Andes region with high insolation and many populated high mountain valleys; and (3) the rainy, Amazon basin covered with jungle, and sparcely populated with high but inconsistent insolation. Since there is little competition with other forms of energy, solar energy shows promise. Passive solar heating of buildings, particularly in the Andes region, is described, as well as the use of solar water heaters. Prototypes are described and illustrated. Industrial use of solar heated water in the wool industry as well as solar food drying and solar desalination are discussed. High temperature applications (electrical generators and refrigeration) as well as photovoltaic systems are discussed briefly. It is concluded that social and political factors are holding back the development of solar energy but a start (in the form of prototypes and demonstration programs) is being made. (MJJ)

ADVANCES IN ZERO ENERGY TRANSPORTATION SYSTEMS

OpenAIRE

Ahmad, Othman

2017-01-01

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

Discovery of stationary operation of quiescent H-mode plasmas with net-zero neutral beam injection torque and high energy confinement on DIII-D

Energy Technology Data Exchange (ETDEWEB)

Burrell, K. H.; Chen, X.; Garofalo, A. M.; Groebner, R. J.; Muscatello, C. M.; Osborne, T. H.; Petty, C. C.; Snyder, P. B. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States); Barada, K.; Rhodes, T. L.; Zeng, L. [University of California-Los Angeles, Los Angeles, California 90024 (United States); Solomon, W. M. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Yan, Z. [University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States)

2016-05-15

Recent experiments in DIII-D [J. L. Luxon et al., in Plasma Physics and Controlled Nuclear Fusion Research 1996 (International Atomic Energy Agency, Vienna, 1987), Vol. I, p. 159] have led to the discovery of a means of modifying edge turbulence to achieve stationary, high confinement operation without Edge Localized Mode (ELM) instabilities and with no net external torque input. Eliminating the ELM-induced heat bursts and controlling plasma stability at low rotation represent two of the great challenges for fusion energy. By exploiting edge turbulence in a novel manner, we achieved excellent tokamak performance, well above the H{sub 98y2} international tokamak energy confinement scaling (H{sub 98y2} = 1.25), thus meeting an additional confinement challenge that is usually difficult at low torque. The new regime is triggered in double null plasmas by ramping the injected torque to zero and then maintaining it there. This lowers E × B rotation shear in the plasma edge, allowing low-k, broadband, electromagnetic turbulence to increase. In the H-mode edge, a narrow transport barrier usually grows until MHD instability (a peeling ballooning mode) leads to the ELM heat burst. However, the increased turbulence reduces the pressure gradient, allowing the development of a broader and thus higher transport barrier. A 60% increase in pedestal pressure and 40% increase in energy confinement result. An increase in the E × B shearing rate inside of the edge pedestal is a key factor in the confinement increase. Strong double-null plasma shaping raises the threshold for the ELM instability, allowing the plasma to reach a transport-limited state near but below the explosive ELM stability boundary. The resulting plasmas have burning-plasma-relevant β{sub N} = 1.6–1.8 and run without the need for extra torque from 3D magnetic fields. To date, stationary conditions have been produced for 2 s or 12 energy confinement times, limited only by external hardware constraints

Solar energy system demonstration project at Wilmington Swim School, New Castle, Delaware

Science.gov (United States)

1980-07-01

A solar energy system located at the Wilmington Swim School, New Castle, Delaware is described. The system was designed for a 40 percent heating and a 30 percent hot water solar contribution serving the heat loads in the following order: space heat - new addition, domestic water - entire facility, and pool heating - entire facility. On a cost basis for 2920 hours of operation, the heat reclaimed would cost $969.66 annually if provided by gas at 3.79 per million Btu's. At 5.5 centers per kwh, heat recovery costs of $481.80 percent a net savings of $487.86 annually.

Solar energy engineering processes and systems

CERN Document Server

Kalogirou, Soteris A

2009-01-01

As perhaps the most promising of all the renewable energy sources available today, solar energy is becoming increasingly important in the drive to achieve energy independence and climate balance. This new book is the masterwork from world-renowned expert Dr. Soteris Kalogirou, who has championed solar energy for decades. The book includes all areas of solar energy engineering, from the fundamentals to the highest level of current research. The author includes pivotal subjects such as solar collectors, solar water heating, solar space heating and cooling, industrial process heat, solar desalina

Solar energy engineering processes and systems

CERN Document Server

Kalogirou, Soteris A

2013-01-01

As perhaps the most promising of all the renewable energy sources available today, solar energy is becoming increasingly important in the drive to achieve energy independence and climate balance. This new book is the masterwork from world-renowned expert Dr. Soteris Kalogirou, who has championed solar energy for decades. The book includes all areas of solar energy engineering, from the fundamentals to the highest level of current research. The author includes pivotal subjects such as solar collectors, solar water heating, solar space heating and cooling, industrial process heat, solar desalina

Solar Transportation, on the critical path to 100% Renewables

Science.gov (United States)

Swenson, R.; Furman, B.

2016-12-01

The path from hydrocarbons and climate change to 100% renewable energy requires a complete transformation of human mobility systems—from oil to solar electricity, and away from personal cars to shared transit. Electric (and autonomous) personal vehicles cannot scale rapidly enough to address CO2 increase and resource depletion. While atmospheric science can characterize the challenge, design science aimed at order of magnitude improvements in energy and resource consumption is needed to achieve carbon free transit that can scale rapidly for urban mobility. An NGO and University engineering team collaboration has led to a multi-disciplinary international program creating prototypes and test tracks to demonstrate the efficacy and economics of solar-powered, automated, non-stop origin-to-destination, elevated on-demand transit systems. With their aptitude for innovation, students in the Solar Skyways challenge have convened from several countries in order to propel development and overcome resistance from the automotive industry incumbency. Innovation has been occurring in lesser developed countries as well as in the industrialized world. An online curriculum has been developed and will be presented to encourage international participation and rapid acceleration for sustainable zero-net-carbon transportation.

In field arsenic removal from natural water by zero-valent iron assisted by solar radiation

International Nuclear Information System (INIS)

Cornejo, Lorena; Lienqueo, Hugo; Arenas, Maria; Acarapi, Jorge; Contreras, David; Yanez, Jorge; Mansilla, Hector D.

2008-01-01

An in situ arsenic removal method applicable to highly contaminated water is presented. The method is based in the use of steel wool, lemon juice and solar radiation. The method was evaluated using water from the Camarones River, Atacama Desert in northern Chile, in which the arsenic concentration ranges between 1000 and 1300 μg L -1 . Response surface method analysis was used to optimize the amount of zero-valent iron (steel wool) and the citrate concentration (lemon juice) to be used. The optimal conditions when using solar radiation to remove arsenic from natural water from the Camarones river are: 1.3 g L -1 of steel wool and one drop (ca. 0.04 mL) of lemon juice. Under these conditions, removal percentages are higher than 99.5% and the final arsenic concentration is below 10 μg L -1 . This highly effective arsenic removal method is easy to use and inexpensive to implement. - An in situ arsenic removal method applicable to highly contaminated waters by using zero-valent iron, citrate and solar radiation was developed

In field arsenic removal from natural water by zero-valent iron assisted by solar radiation

Energy Technology Data Exchange (ETDEWEB)

Cornejo, Lorena [Departamento de Quimica, Facultad de Ciencias, Universidad de Tarapaca, Casilla 7-D, Arica (Chile); Laboratorio de Investigaciones Medioambientales de Zonas Aridas, LIMZA, Centro de Investigaciones del Hombre en el Desierto, CIHDE, Arica (Chile)], E-mail: lorenacp@uta.cl; Lienqueo, Hugo; Arenas, Maria [Departamento de Quimica, Facultad de Ciencias, Universidad de Tarapaca, Casilla 7-D, Arica (Chile); Acarapi, Jorge [Departamento de Quimica, Facultad de Ciencias, Universidad de Tarapaca, Casilla 7-D, Arica (Chile); Laboratorio de Investigaciones Medioambientales de Zonas Aridas, LIMZA, Centro de Investigaciones del Hombre en el Desierto, CIHDE, Arica (Chile); Contreras, David; Yanez, Jorge; Mansilla, Hector D. [Facultad de Ciencias Quimicas, Universidad de Concepcion, Casilla 160C, Concepcion (Chile)

2008-12-15

An in situ arsenic removal method applicable to highly contaminated water is presented. The method is based in the use of steel wool, lemon juice and solar radiation. The method was evaluated using water from the Camarones River, Atacama Desert in northern Chile, in which the arsenic concentration ranges between 1000 and 1300 {mu}g L{sup -1}. Response surface method analysis was used to optimize the amount of zero-valent iron (steel wool) and the citrate concentration (lemon juice) to be used. The optimal conditions when using solar radiation to remove arsenic from natural water from the Camarones river are: 1.3 g L{sup -1} of steel wool and one drop (ca. 0.04 mL) of lemon juice. Under these conditions, removal percentages are higher than 99.5% and the final arsenic concentration is below 10 {mu}g L{sup -1}. This highly effective arsenic removal method is easy to use and inexpensive to implement. - An in situ arsenic removal method applicable to highly contaminated waters by using zero-valent iron, citrate and solar radiation was developed.

Financial investments for zero energy houses

DEFF Research Database (Denmark)

Lepkova, Natalija; Zubka, Domantas; Jensen, Rasmus Lund

2014-01-01

The climate is constantly changing and is already affecting our future. The construction sector has become energy-intensive and a serious source of pollution. Today, houses use more energy and fossil fuels than ever before. In fact, buildings currently consume more than one-third of all energy......, but single-family houses should also be included in the renovation process and turned into zero energy buildings, which will be the standard in the near future of today’s construction sector. Read about the list of conclusions the investigations of a renovation project of a detached house into a nearzero...

Solar Energy Development PEIS Information Center

Science.gov (United States)

skip navigation Solar Energy Development Programmatic EIS Home About the EIS Public Involvement Solar Energy Solar Energy Zones Maps Documents secondary menu News Frequently Asked Questions Glossary E the Programmatic Environmental Impact Statement for Solar Energy Development in Six Southwestern

A normative price for energy from an electricity generation system: An Owner-dependent Methodology for Energy Generation (system) Assessment (OMEGA). Volume 2: Derivation of system energy price equations

Science.gov (United States)

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

1981-01-01

The methodology presented is a derivation of the utility owned solar electric systems model. The net present value of the system is determined by consideration of all financial benefits and costs including a specified return on investment. Life cycle costs, life cycle revenues, and residual system values are obtained. Break-even values of system parameters are estimated by setting the net present value to zero.

Solar Energy Technologies Office Fact Sheet

Energy Technology Data Exchange (ETDEWEB)

Solar Energy Technologies Office

2018-03-13