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Characterization of Alternative Hybrid Solar Thermal Electric Systems

Description: Hybrid power towers offer a number of advantages over solar-only power tower systems for early commercial deployment of the technology. These advantages include enhanced modularity, reduced financial and technical risks, and lower energy costs. With the changes in the domestic and world markets for bulk power, hybrid power towers are likely to have the best opportunities for power projects. This paper discusses issues that are likely to be important to the deployment of hybrid power towers in the near future. A large number of alternative designs are possible, and it is likely that there is no single approach that can be considered best or optimal for all project opportunities. The preferred design will depend on the application, as well as the unique objectives and perspectives of the person evaluating the design.
Date: May 18, 1999
Creator: Williams, T. A.
Partner: UNT Libraries Government Documents Department

An engineering-economic analysis of combined heat and power technologies in a (mu)grid application

Description: This report describes an investigation at Ernesto Orlando Lawrence Berkeley National Laboratory (Berkeley Lab) of the potential for coupling combined heat and power (CHP) with on-site electricity generation to provide power and heating, and cooling services to customers. This research into distributed energy resources (DER) builds on the concept of the microgrid (mGrid), a semiautonomous grouping of power-generating sources that are placed and operated by and for the benefit of its members. For this investigation, a hypothetical small shopping mall (''Microgrid Oaks'') was developed and analyzed for the cost effectiveness of installing CHP to provide the mGrid's energy needs. A mGrid consists of groups of customers pooling energy loads and installing a combination of generation resources that meets the particular mGrid's goals. This study assumes the mGrid is seeking to minimize energy costs. mGrids could operate independently of the macrogrid (the wider power network), but they are usually assumed to be connected, through power electronics, to the macrogrid. The mGrid in this study is assumed to be interconnected to the macrogrid, and can purchase some energy and ancillary services from utility providers.
Date: March 1, 2002
Creator: Bailey, Owen; Ouaglal, Boubekeur; Bartholomew, Emily; Marnay, Chris & Bourassa, Norman
Partner: UNT Libraries Government Documents Department

Reducing Leaking Electricity to 1 Watt

Description: In this study we examine some specific opportunities toreduce standby losses in electronic appliances. A review of powerconsumption levels for the major components responsible for standbyfunctions indicates that nearly all standby functions can be performedwith a total appliance standby power consumption of one watt or less. Wetherefore propose that standby losses be limited to one watt perappliance, a significant reduction from current levels for manyappliances. This target could be achieved with little or no extra cost tomanufacturers and could save over $2 billion in annual U.S. energy costs.Globally, a one-watt plan would lead to a significant reduction in carbonemissions.
Date: August 1, 1998
Creator: Meier, A.K.; Huber, Wolfgang & Rosen, Karen
Partner: UNT Libraries Government Documents Department

Characterizing the Response of Commercial and Industrial Facilities to Dynamic Pricing Signals from the Utility

Description: We describe a method to generate statistical models of electricity demand from Commercial and Industrial (C&I) facilities including their response to dynamic pricing signals. Models are built with historical electricity demand data. A facility model is the sum of a baseline demand model and a residual demand model; the latter quantifies deviations from the baseline model due to dynamic pricing signals from the utility. Three regression-based baseline computation methods were developed and analyzed. All methods performed similarly. To understand the diversity of facility responses to dynamic pricing signals, we have characterized the response of 44 C&I facilities participating in a Demand Response (DR) program using dynamic pricing in California (Pacific Gas and Electric's Critical Peak Pricing Program). In most cases, facilities shed load during DR events but there is significant heterogeneity in facility responses. Modeling facility response to dynamic price signals is beneficial to the Independent System Operator for scheduling supply to meet demand, to the utility for improving dynamic pricing programs, and to the customer for minimizing energy costs.
Date: July 1, 2010
Creator: Mathieu, Johanna L.; Gadgil, Ashok J.; Callaway, Duncan S.; Price, Phillip N. & Kiliccote, Sila
Partner: UNT Libraries Government Documents Department

Physical Energy Accounting in California: A Case Study of Cellulosic Ethanol Production

Description: California's target for greenhouse gas reduction in part relies on the development of viable low-carbon fuel alternatives to gasoline. It is often assumed that cellulosic ethanol--ethanol made from the structural parts of a plant and not from the food parts--will be one of these alternatives. This study examines the physical viability of a switchgrass-based cellulosic ethanol industry in California from the point of view of the physical requirements of land, water, energy and other material use. Starting from a scenario in which existing irrigated pastureland and fiber-crop land is converted to switchgrass production, the analysis determines the total acreage and water supply available and the resulting total biofuel feedstock output under different assumed yields. The number and location of cellulosic ethanol biorefineries that can be supported is also determined, assuming that the distance from field to biorefinery would be minimized. The biorefinery energy input requirement, available energy from the fraction of biomass not converted to ethanol, and energy output is calculated at various levels of ethanol yields, making different assumptions about process efficiencies. The analysis shows that there is insufficient biomass (after cellulose separation and fermentation into ethanol) to provide all the process energy needed to run the biorefinery; hence, the purchase of external energy such as natural gas is required to produce ethanol from switchgrass. The higher the yield of ethanol, the more external energy is needed, so that the net gains due to improved process efficiency may not be positive. On 2.7 million acres of land planted in switchgrass in this scenario, the switchgrass outputproduces enough ethanol to substitute for only 1.2 to 4.0percent of California's gasoline consumption in 2007.
Date: July 17, 2008
Creator: Coughlin, Katie & Fridley, David
Partner: UNT Libraries Government Documents Department

Thermal Energy Storage for Space Cooling--Federal Technology Alert

Description: Cool storage technology can be used to significantly reduce energy costs by allowing energy-intensive, electrically driven cooling equipment to be predominantly operated during off peak hours when electricity rates are lower. This Federal Technology Alert, which is sponsored by DOE's Federal Energy Management Program (FEMP), describes the basic types of cool storage technologies and cooling system integration options. In addition, it defines the savings potential in the federal sector, presents application advice, and describes the performance experience of specific federal users. The results of a case study of a GSA building using cool storage technology are also provided.
Date: December 31, 2000
Creator: Brown, Daryl R
Partner: UNT Libraries Government Documents Department

An Analysis of the Effects of Residential Photovoltaic Energy Systems on Home Sales Prices in California

Description: An increasing number of homes in the U.S. have sold with photovoltaic (PV) energy systems installed at the time of sale, yet relatively little research exists that estimates the marginal impacts of those PV systems on home sale prices. A clearer understanding of these possible impacts might influence the decisions of homeowners considering the installation of a PV system, homebuyers considering the purchase of a home with PV already installed, and new home builders considering including PV as an optional or standard product on their homes. This research analyzes a large dataset of California homes that sold from 2000 through mid-2009 with PV installed. It finds strong evidence that homes with PV systems sold for a premium over comparable homes without PV systems during this time frame. Estimates for this premium expressed in dollars per watt of installed PV range, on average, from roughly $4 to $5.5/watt across a large number of hedonic and repeat sales model specifications and robustness tests. When expressed as a ratio of the sales price premium of PV to estimated annual energy cost savings associated with PV, an average ratio of 14:1 to 19:1 can be calculated; these results are consistent with those of the more-extensive existing literature on the impact of energy efficiency on sales prices. When the data are split among new and existing homes, however, PV system premiums are markedly affected. New homes with PV show premiums of $2.3-2.6/watt, while existing homes with PV show premiums of more than $6/watt. Reasons for this discrepancy are suggested, yet further research is warranted. A number of other areas where future research would be useful are also highlighted.
Date: April 19, 2011
Creator: Hoen, Ben; Cappers, Peter; Wiser, Ryan & Thayer, Mark
Partner: UNT Libraries Government Documents Department

Changing ventilation rates in U.S. offices: Implications for health, work performance, energy, and associated economics

Description: This paper provides quantitative estimates of benefits and costs of providing different amounts of outdoor air ventilation in U.S. offices. For four scenarios that modify ventilation rates, we estimated changes in sick building syndrome (SBS) symptoms, work performance, short-term absence, and building energy consumption. The estimated annual economic benefits were $13 billion from increasing minimum ventilation rates (VRs) from 8 to 10 L/s per person, $38 billion from increasing minimum VRs from 8 to 15 L/s per person, and $33 billion from increasing VRs by adding outdoor air economizers for the 50% of the office floor area that currently lacks economizers. The estimated $0.04 billion in annual energy-related benefits of decreasing minimum VRs from 8 to 6.5 L/s per person are very small compared to the projected annual costs of $12 billion. Benefits of increasing minimum VRs far exceeded energy costs while adding economizers yielded health, performance, and absence benefits with energy savings.
Date: July 1, 2011
Creator: Fisk, William; Black, Douglas & Brunner, Gregory
Partner: UNT Libraries Government Documents Department

Best Practice for Energy Efficient Cleanrooms:Minienvironments

Description: Cleanroom air-recirculation systems typically account for a significant portion of the HVAC energy use in cleanrooms. High electric power density is normally required for fans to deliver large volume of airflows that were designed, supplied, recirculated, and exhausted within a given time. With the increasing demand for specific contamination control, it is important to optimize design of clean spaces. Best practice in cleanroom air system design includes right-sizing the systems in cleanrooms and adopting minienvironments. Implementing and integrating minienvironments in cleanrooms can improve contamination control and save significant energy. A minienvironment is a localized environment created by an enclosure to isolate a product or process from the surrounding environment. The advantages in using minienvironments include the following: (1) Minienvironments may create better contamination control and process integration. (2) Minienvironments may maintain better contamination control by better control of pressure difference or through use of unidirectional airflows, e.g., cleanliness-class upgrade required for certain process. (3) Minienvironments may potentially reduce energy costs. The use of fan-filter units (FFU) in minienvironments is common. The energy efficiency of such air-delivery systems can vary significantly because of the difference in energy performance, airflow paths, and operating conditions. Simply adding minienvironments with fan-filter units in an existing cleanroom will increase power density and energy intensity for delivering airflow in the space served, if everything else is unchanged. However, by considering contamination control requirements in the various spaces minienvironments can be integrated with the surrounding cleanroom to optimize the overall electric power demand for the facility and to achieve specific cleanliness in each area. In addition, selecting energy efficient minienvironment systems will further improve the overall energy efficiency of the clean spaces.
Date: June 15, 2005
Creator: Xu, Tengfang
Partner: UNT Libraries Government Documents Department

Vacuum Technology

Description: The environmental condition called vacuum is created any time the pressure of a gas is reduced compared to atmospheric pressure. On earth we typically create a vacuum by connecting a pump capable of moving gas to a relatively leak free vessel. Through operation of the gas pump the number of gas molecules per unit volume is decreased within the vessel. As soon as one creates a vacuum natural forces (in this case entropy) work to restore equilibrium pressure; the practical effect of this is that gas molecules attempt to enter the evacuated space by any means possible. It is useful to think of vacuum in terms of a gas at a pressure below atmospheric pressure. In even the best vacuum vessels ever created there are approximately 3,500,000 molecules of gas per cubic meter of volume remaining inside the vessel. The lowest pressure environment known is in interstellar space where there are approximately four molecules of gas per cubic meter. Researchers are currently developing vacuum technology components (pumps, gauges, valves, etc.) using micro electro mechanical systems (MEMS) technology. Miniature vacuum components and systems will open the possibility for significant savings in energy cost and will open the doors to advances in electronics, manufacturing and semiconductor fabrication. In conclusion, an understanding of the basic principles of vacuum technology as presented in this summary is essential for the successful execution of all projects that involve vacuum technology. Using the principles described above, a practitioner of vacuum technology can design a vacuum system that will achieve the project requirements.
Date: October 15, 2004
Creator: Biltoft, P. J.
Partner: UNT Libraries Government Documents Department

Estimating the Cost of Superconducting Magnets and the Refrigerators Needed to Keep Them Cold

Description: The cost of superconducting magnets and the refrigerators needed to keep them cold can be estimated if one knows the magnet stored energy and the amount of refrigeration needed. This report updates the cost data collected over 20 years ago by Strobridge and others. Early cost data has been inflated into 1991 dollars and data on newer superconducting magnets has been added to the old data. The cost of superconducting magnets has been correlated with stored energy and field-magnetic volume product. The cost of the helium refrigerator cold box and the compressors needed to keep the magnet cold can be correlated with the refrigeration generated at 4.5K. The annual cost of 4.5K refrigeration can be correlated with 4.5K refrigeration and electrical energy cost.
Date: June 1, 1991
Creator: Green, M. A.; Byrns, R. & St. Lorant, S. J.
Partner: UNT Libraries Government Documents Department

Short-term energy outlook. Quarterly projections, second quarter 1996

Description: The Energy Information Administration prepares quarterly, short-term energy supply, demand, and price projections. The forecasts in this issue cover the second quarter of 1996 through the fourth quarter of 1997. Changes to macroeconomic measures by the Bureau of Economic Analysis have been incorporated into the STIFS model used.
Date: April 1, 1996
Partner: UNT Libraries Government Documents Department

University of Nevada Las Vegas LED Display Engineering

Description: The primary objective of this part of the project is to develop and implement a method that compensates for the inefficiency of the green LED. The proposed engineering solution which will be the backbone of this project will be to use RGBW combination in every pixel to save energy. Two different RGBW geometrical pixel configurations will be implemented and compared against traditional LED configurations. These configurations will be analyzed for energy efficiency while keeping the quality of the display the same. Cost of the addition of white LEDs to displays along with energy cost savings will be presented and analyzed.
Date: August 31, 2010
Partner: UNT Libraries Government Documents Department

National Energy and Cost Savings for New Single- and Multifamily Homes: A Comparison of the 2006, 2009, and 2012 Editions of the IECC

Description: The 2009 and 2012 International Energy Conservation Code (IECC) yield positive benefits for U.S. homeowners and significant energy savings for the nation. Moving from a baseline of the 2006 IECC to the 2009 IECC reduces average annual energy costs by 10.8%, while moving from the same baseline to the 2012 IECC reduces them by 32.1%. These reductions amount to annual energy cost savings of $168 and $497, respectively. The 2012 IECC saves $329 in energy costs compared to the 2009 IECC.
Date: April 1, 2012
Creator: Lucas, Robert G.; Taylor, Zachary T.; Mendon, Vrushali V. & Goel, Supriya
Partner: UNT Libraries Government Documents Department

You Have the Power campaign. Final technical report for the period January 1, 1999 through September 30, 1999

Description: The Federal Energy Management Program (FEMP) must help Federal agencies reduce energy costs by delivering effective outreach programs. It is crucial that all professionals involved with the management of Federal facilities receive a clear message that FEMP offers effective information, education, tools, training, and resources. To achieve this objective, American Ideas and Designs, Inc., d/b/a Greening America, assisted FEMP in continuing a comprehensive energy efficiency outreach program titled ''You Have the Power.'' The ''You Have the Power'' campaign emphasized the ability of individual Federal employees, Federal agencies, and stakeholder organizations to easily access FEMP's energy efficiency tools and resources through a set of integrated interagency delivery programs.
Date: October 29, 1999
Creator: Costello, Carl D.
Partner: UNT Libraries Government Documents Department

Supplement to the annual energy outlook 1994

Description: This report is a companion document to the Annual Energy Outlook 1994 (AEO94), (DOE/EIA-0383(94)), released in Jan. 1994. Part I of the Supplement presents the key quantitative assumptions underlying the AEO94 projections, responding to requests by energy analysts for additional information on the forecasts. In Part II, the Supplement provides regional projections and other underlying details of the reference case projections in the AEO94. The AEO94 presents national forecasts of energy production, demand and prices through 2010 for five scenarios, including a reference case and four additional cases that assume higher and lower economic growth and higher and lower world oil prices. These forecasts are used by Federal, State, and local governments, trade associations, and other planners and decisionmakers in the public and private sectors.
Date: March 1, 1994
Creator: United States. Department of Energy. Energy Information Administration
Partner: UNT Libraries Government Documents Department

Rural Energy Conference Project

Description: Alaska remains, even at the beginning of the 21st century, a place with many widely scattered, small, remote communities, well beyond the end of both the road system and the power grid. These communities have the highest energy costs of any place in the United States, despite the best efforts of the utilities that service them. This is due to the widespread dependence on diesel electric generators, which require small capital investments, but recent increases in crude oil prices have resulted in dramatic increases in the cost of power. In the enabling legislation for the Arctic Energy Office in 2001, specific inclusion was made for the study of ways of reducing the cost of electrical power in these remote communities. As part of this mandate, the University of Alaska has, in conjunction with the US Department of Energy, the Denali Commission and the Alaska Energy Authority, organized a series of rural energy conferences, held approximately every 18 months. The goal of these meeting was to bring together rural utility operators, rural community leaders, government agency representatives, equipment suppliers, and researchers from universities and national laboratories to discuss the current state of the art in rural power generation, to discuss current projects, including successes as well as near successes. Many of the conference presenters were from industry and not accustomed to writing technical papers, so the typical method of organizing a conference by requesting abstracts and publishing proceedings was not considered viable. Instead, the organizing committee solicited presentations from appropriate individuals, and requested that (if they were comfortable with computers) prepare Power point presentations that were collected and posted on the web. This has become a repository of many presentations, and may be the best single source of information about current projects in the state of Alaska.
Date: December 31, 2008
Creator: Witmer, Dennis & Watson, Shannon
Partner: UNT Libraries Government Documents Department

Long-Term Modeling of Solar Energy: Analysis of Concentrating Solar Power (CSP) and PV Technologies

Description: This report presents an overview of research conducted on solar energy technologies and their implementation in the ObjECTS framework. The topics covered include financing assumptions and selected issues related to the integration of concentrating thermal solar power (CSP) and photovoltaics PV technologies into the electric grid. A review of methodologies for calculating the levelized energy cost of capital-intensive technologies is presented, along with sensitivity tests illustrating how the cost of a solar plant would vary depending on financing assumptions. An analysis of the integration of a hybrid concentrating thermal solar power (CSP) system into the electric system is conducted. Finally a failure statistics analysis for PV plants illustrates the central role of solar irradiance uncertainty in determining PV grid integration characteristics.
Date: August 16, 2007
Creator: Zhang, Yabei & Smith, Steven J.
Partner: UNT Libraries Government Documents Department

Monitoring Based Commissioning: Benchmarking Analysis of 24 UC/CSU/IOU Projects

Description: Buildings rarely perform as intended, resulting in energy use that is higher than anticipated. Building commissioning has emerged as a strategy for remedying this problem in non-residential buildings. Complementing traditional hardware-based energy savings strategies, commissioning is a 'soft' process of verifying performance and design intent and correcting deficiencies. Through an evaluation of a series of field projects, this report explores the efficacy of an emerging refinement of this practice, known as monitoring-based commissioning (MBCx). MBCx can also be thought of as monitoring-enhanced building operation that incorporates three components: (1) Permanent energy information systems (EIS) and diagnostic tools at the whole-building and sub-system level; (2) Retro-commissioning based on the information from these tools and savings accounting emphasizing measurement as opposed to estimation or assumptions; and (3) On-going commissioning to ensure efficient building operations and measurement-based savings accounting. MBCx is thus a measurement-based paradigm which affords improved risk-management by identifying problems and opportunities that are missed with periodic commissioning. The analysis presented in this report is based on in-depth benchmarking of a portfolio of MBCx energy savings for 24 buildings located throughout the University of California and California State University systems. In the course of the analysis, we developed a quality-control/quality-assurance process for gathering and evaluating raw data from project sites and then selected a number of metrics to use for project benchmarking and evaluation, including appropriate normalizations for weather and climate, accounting for variations in central plant performance, and consideration of differences in building types. We performed a cost-benefit analysis of the resulting dataset, and provided comparisons to projects from a larger commissioning 'Meta-analysis' database. A total of 1120 deficiency-intervention combinations were identified in the course of commissioning the projects described in this report. The most common location of deficiencies was in HVAC equipment (65% of sites), followed by air-handling and ...
Date: April 1, 2009
Creator: Mills, Evan & Mathew, Paul
Partner: UNT Libraries Government Documents Department

A Successful Case Study of Small Business Energy Efficiency and Demand Response with Communicating Thermostats

Description: This report documents a field study of 78 small commercial customers in the Sacramento Municipal Utility District service territory who volunteered for an integrated energy-efficiency/demand-response (EE-DR) program in the summer of 2008. The original objective for the pilot was to provide a better understanding of demand response issues in the small commercial sector. Early findings justified a focus on offering small businesses (1) help with the energy efficiency of their buildings in exchange for occasional load shed, and (2) a portfolio of options to meet the needs of a diverse customer sector. To meet these expressed needs, the research pilot provided on-site energy efficiency advice and offered participants several program options, including the choice of either a dynamic rate or monthly payment for air-conditioning setpoint control. Overall results show that pilot participants had energy savings of 20%, and the potential for an additional 14% to 20% load drop during a 100 F demand response event. In addition to the efficiency-related bill savings, participants on the dynamic rate saved an estimated 5% on their energy costs compared to the standard rate. About 80% of participants said that the program met or surpassed their expectations, and three-quarters said they would probably or definitely participate again without the $120 participation incentive. These results provide evidence that energy efficiency programs, dynamic rates and load control programs can be used concurrently and effectively in the small business sector, and that communicating thermostats are a reliable tool for providing air-conditioning load shed and enhancing the ability of customers on dynamic rates to respond to intermittent price events.
Date: August 12, 2009
Creator: Herter, Karen; Wayland, Seth & Rasin, Josh
Partner: UNT Libraries Government Documents Department

Seismic and Rockphysics Diagnostics of Multiscale Reservoir Textures

Description: This final technical report summarizes the results of the work done in this project. The main objective was to quantify rock microstructures and their effects in terms of elastic impedances in order to quantify the seismic signatures of microstructures. Acoustic microscopy and ultrasonic measurements were used to quantify microstructures and their effects on elastic impedances in sands and shales. The project led to the development of technologies for quantitatively interpreting rock microstructure images, understanding the effects of sorting, compaction and stratification in sediments, and linking elastic data with geologic models to estimate reservoir properties. For the public, ultimately, better technologies for reservoir characterization translates to better reservoir development, reduced risks, and hence reduced energy costs.
Date: July 1, 2005
Creator: Mavko, Gary
Partner: UNT Libraries Government Documents Department

Multiparameter Optimization Studies on Geothermal Energy Cycles

Description: Various standard geothermal power cycles are modeled and optimized with program GEOTHM. The results are displayed in 3-D isometric form. These graphical plots vividly display the sensitivity of energy cost and other performance criteria as a result of departures from the design operating point. For example, we will present the mutual interaction of energy cost, resource utilization efficiency, and resource temperature as an EC-RUE-RT surface for a range of temperatures between 100 C and 300 C. Calculation results will be presented for subcritical and supercritical binary cycles with several pure fluids, and on two stage flashed steam cycles for practical non-condensable gas levels.
Date: August 1, 1977
Creator: Pope, W.L.; Pines, H.S.; Silvester, L.F.; Green, M.A. & Williams, J.D.
Partner: UNT Libraries Government Documents Department

MARKAL-MACRO: A methodology for informed energy, economy and environmental decision making. Informal report

Description: Since the mid-1970`s, energy system analysts have been using models to represent the complexities of interactions in energy systems to help shape policy. Since the mid-1980`s, heightened awareness has made it necessary also to consider the environmental impacts of energy policies. MARKAL is a cost-minimizing energy-environment system planning model used to explore mid- to long-term responses to different technological futures, emissions limitations, and policy scenarios. MARKAL-MACRO is an extension of MARKAL that integrates these capabilities directly with a neoclassical macroeconomic growth model. By combining bottom-up engineering and top-down macroeconomic approaches in a single modeling framework, MARKAL-MACR is able to capture the interplay between the energy system, the economy and the environment, allowing the affects on demands of endogenously determined energy prices to be explored.
Date: May 16, 1995
Creator: Goldstein, G.A.
Partner: UNT Libraries Government Documents Department

DOE`s project-oriented SAVEnergy audit program

Description: The SAVEnergy program was developed as a result of the Energy Policy Act of 1992 which mandated that the Secretary of Energy establish audit teams. The SAVEnergy program complies with Federal legislation that requires government agencies to function with slightly different parameters than the private commercial sector. This program has proven enormously popular and successful with Federal agencies. This paper addresses those components considered during program development that were built in to ensure program success. This paper will discuss how this program was successful in leading to project implementation and how SAVEnergy can serve as a model to other Federal, utility, and private sector programs.
Date: October 1, 1995
Creator: Mayo, K.
Partner: UNT Libraries Government Documents Department