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A Green Prison: Santa Rita Jail Creeps Towards Zero Net Energy (ZNE)

Description: 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.
Date: March 18, 2011
Creator: Marnay, Chris; DeForest, Nicholas; Stadler, Michael; Donadee, Jon; Dierckxsens, Carlos; Mendes, Goncalo et al.
Partner: UNT Libraries Government Documents Department

A Green Prison: The Santa Rita Jail Campus Microgrid

Description: A large microgrid project is nearing completion at Alameda County’s twenty-two-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 (DER) including an eight-year old 1.2 MW PV array, a five-year old 1 MW fuel cell with heat recovery, and considerable efficiency investments. A current US$14 M expansion adds a 2 MW-4 MWh Li-ion battery, a static disconnect switch, and various controls upgrades. During grid blackouts, or when conditions favor it, the Jail can now disconnect from the grid and operate as an island, using the on-site resources described together with its back-up diesel generators. In other words, the Santa Rita Jail is a true microgrid, or μgrid, because it fills both requirements, i.e. it is a locally controlled system, and it can operate both grid connected and islanded. The battery’s electronics includes Consortium for Electric Reliability Technology (CERTS) Microgrid technology. This enables the battery to maintain energy balance using droops without need for a fast control system.
Date: January 22, 2012
Creator: Marnay, Chris; DeForest, Nicholas & Lai, Judy
Partner: UNT Libraries Government Documents Department

Heat Pump Water Heaters and American Homes: A Good Fit?

Description: Heat pump water heaters (HPWHs) are over twice as energy-efficient as conventional electric resistance water heaters, with the potential to save substantial amounts of electricity. Drawing on analysis conducted for the U.S. Department of Energy's recently-concluded rulemaking on amended standards for water heaters, this paper evaluates key issues that will determine how well, and to what extent, this technology will fit in American homes. The key issues include: 1) equipment cost of HPWHs; 2) cooling of the indoor environment by HPWHs; 3) size and air flow requirements of HPWHs; 4) performance of HPWH under different climate conditions and varying hot water use patterns; and 5) operating cost savings under different electricity prices and hot water use. The paper presents the results of a life-cycle cost analysis of the adoption of HPWHs in a representative sample of American homes, as well as national impact analysis for different market share scenarios. Assuming equipment costs that would result from high production volume, the results show that HPWHs can be cost effective in all regions for most single family homes, especially when the water heater is not installed in a conditioned space. HPWHs are not cost effective for most manufactured home and multi-family installations, due to lower average hot water use and the water heater in the majority of cases being installed in conditioned space, where cooling of the indoor environment and size and air flow requirements of HPWHs increase installation costs.
Date: May 14, 2010
Creator: Franco, Victor; Lekov, Alex; Meyers, Steve & Letschert, Virginie
Partner: UNT Libraries Government Documents Department


Description: A turbulent reacting shear layer in a premixed propane/air flow has been studied in a two dimensional combustor, with the flame stabilized behind a rearward facing streamlined step. Spark shadowgraphs show that in the range of velocities (7.5 to 22.5 m/sec corresponding to Reynolds numbers of .5 x 10{sup 4} cm{sup -1} to 1. 5 x 10{sup 4} cm{sup -1} ) and equivalence ratios (0.4 to 0.7) studied, the mixing layer is dominated by Brown~ Roshko type large coherent structures in both reacting and nonreacting flows. High speed schlieren movies show that these eddies are convected downstream and increase their size and spacing by combustion and coalescence with neighboring eddies. Tracing individual eddies shows, in the reacting shear layer, that, on the average, eddies accelerate as they move downstream with the highest acceleration close to the origin of the shear layer. Combustion is confined to these large structures which develop as a result of vortical action of the shear flow. On the average, the reacting eddies have a lower growth rate than nonreacting eddies. A turbulent boundary layer created by means of a tripping wire upstream of the edge of the step virtually eliminates the large coherent structures in the shear layer, while for the case in which the wire could not trigger the transition to turbulence, the large coherent structures dominated the reacting and nonreacting flows.
Date: April 1, 1980
Creator: Ganji, A.R. & Sawyer, R.F.
Partner: UNT Libraries Government Documents Department

Exploration of Resource and Transmission Expansion Decisions in the Western Renewable Energy Zone Initiative

Description: The Western Renewable Energy Zone (WREZ) initiative brings together a diverse set of voices to develop data, tools, and a unique forum for coordinating transmission expansion in the Western Interconnection. In this paper we use a new tool developed in the WREZ initiative to evaluate possible renewable resource selection and transmission expansion decisions. We evaluate these decisions under a number of alternative future scenarios centered on meeting 33percent of the annual load in the Western Interconnection with new renewable resources located within WREZ-identified resource hubs. Our analysis finds that wind energy is the largest source of renewable energy procured to meet the 33percent RE target across nearly all scenarios analyzed (38-65percent). Solar energy is almost always the second largest source (14-41percent). We find several load zones where wind energy is the least cost resource under a wide range of sensitivity scenarios. Load zones in the Southwest, on the other hand, are found to switch between wind and solar, and therefore to vary transmission expansion decisions, depending on uncertainties and policies that affect the relative economics of each renewable option. Further, we find that even with total transmission expenditures of $17-34 billion these costs still represent just 10-19percent of the total delivered cost of renewable energy.
Date: June 10, 2010
Creator: Mills, Andrew D.; Phadke, Amol A. & Wiser, Ryan H.
Partner: UNT Libraries Government Documents Department

Facilitating Energy Savings through Enhanced Usability of Thermostats

Description: Residential thermostats play a key role in controlling heating and cooling systems. Occupants often find the controls of programmable thermostats confusing, sometimes leading to higher heating consumption than when the buildings are controlled manually. A high degree of usability is vital to a programmable thermostat's effectiveness because, unlike a more efficient heating system, occupants must engage in specific actions after installation to obtain energy savings. We developed a procedure for measuring the usability of thermostats and tested this methodology with 31 subjects on five thermostats. The procedure requires first identifying representative tasks associated with the device and then testing the subjects ability to accomplish those tasks. The procedure was able to demonstrate the subjects wide ability to accomplish tasks and the influence of a device's usability on success rates. A metric based on the time to accomplish the tasks and the fraction of subjects actually completing the tasks captured the key aspects of each thermostat's usability. The procedure was recently adopted by the Energy Star Program for its thermostat specification. The approach appears suitable for quantifying usability of controls in other products, such as heat pump water heaters and commercial lighting.
Date: May 23, 2011
Creator: Meier, Alan; Aragon, Cecilia; Peffer, Therese; Perry, Daniel & Pritoni, Marco
Partner: UNT Libraries Government Documents Department

Factors Affecting Indoor Air Concentrations of Volatile Organic Compounds at a Site of Subsurface Gasoline Contamination

Description: We report a field study of soil gas transport of volatile organic compounds (VOCs) into a slab-on-grade building found at a site contaminated with gasoline. Although the high VOC concentrations (30-60 g m{sup -3}) measured in the soil gas at depths of 0.7 m below the building suggest a potential for high levels of indoor VOC, the measured indoor air concentrations were lower than those in the soil gas by approximately six orders of magnitude ({approx} 0.03 mg m{sup -3}). This large ratio is explained by (1) the expected dilution of soil gas entering the building via ambient building ventilation (a factor of {approx}1000), and (2) an unexpectedly sharp gradient in soil gas VOC concentration between the depths of 0.1 and 0.7 m (a factor of {approx}1000). Measurements of the soil physical and biological characteristics indicate that a partial physical barrier to vertical transport in combination with microbial degradation provides a likely explanation for this gradient. These factors are likely to be important to varying degrees at other sites.
Date: November 1, 1995
Creator: Fischer, M. L.; Bentley, A. J.; Dunkin, K. A.; Hodgson, A. T.; Nazaroff, W. W.; Sextro, R. G. et al.
Partner: UNT Libraries Government Documents Department


Description: Inorganic arsenic and organoarsenic compounds were speciated in seven oil shale retort and process waters, including samples from simulated, true and modified in situ processes, using a high performance liquid chromatograph automatically coupled to a graphite furnace atomic absorption detector. The molecular forms of arsenic at ppm levels (({micro}g/mL) in these waters are identified for the first time, and shown to include arsenate, methylarsonic acid and phenylarsonic acid. An arsenic-specific fingerprint chromatogram of each retort or process water studied has significant impliestions regarding those arsenical species found and those marginally detected, such as dimethylarsinic acid and the suspected carcinogen arsenite. The method demonstrated suggests future means for quantifying environmental impacts of bioactive organometal species involved in oil shale retorting technology.
Date: July 1, 1981
Creator: Fish, Richard H.; Brinckman, Frederick E. & Jewett, Kenneth L.
Partner: UNT Libraries Government Documents Department

A Framework for the Evaluation of the Cost and Benefits of Microgrids

Description: A Microgrid is recognized as an innovative technology to help integrate renewables into distribution systems and to provide additional benefits to a variety of stakeholders, such as offsetting infrastructure investments and improving the reliability of the local system. However, these systems require additional investments for control infrastructure, and as such, additional costs and the anticipated benefits need to be quantified in order to determine whether the investment is economically feasible. This paper proposes a methodology for systematizing and representing benefits and their interrelationships based on the UML Use Case paradigm, which allows complex systems to be represented in a concise, elegant format. This methodology is demonstrated by determining the economic feasibility of a Microgrid and Distributed Generation installed on a typical Canadian rural distribution system model as a case study. The study attempts to minimize the cost of energy served to the community, considering the fixed costs associated with Microgrids and Distributed Generation, and suggests benefits to a variety of stakeholders.
Date: July 15, 2011
Creator: Morris, Greg Young; Abbey, Chad; Joos, Geza & Marnay, Chris
Partner: UNT Libraries Government Documents Department


Description: Field effect transistors have been fabricated on high-purity germanium substrates using low-temperature technology. The aim of this work is to preserve the low density of trapping centers in high-quality starting material by low-temperature (< 350 C) processing. The use of germanium promises to eliminate some of the traps which cause generation-recombination noise in silicon field-effect transistors (FET's) at low temperatures. Typically, the transconductance (g{sub m}) in the germanium FET's is 10 mA/V and the gate leakage can be less than 10{sup -12} A. Our present devices exhibit a large 1/f noise component and most of this noise must be eliminated if they are to be competitive with silicon FET's commonly used in high-resolution nuclear spectrometers.
Date: November 1, 1978
Creator: Hansen, William L.; Goulding, Frederick S. & Haller, Eugene E.
Partner: UNT Libraries Government Documents Department

"Hot" for Warm Water Cooling

Description: Liquid cooling is key to reducing energy consumption for this generation of supercomputers and remains on the roadmap for the foreseeable future. This is because the heat capacity of liquids is orders of magnitude larger than that of air and once heat has been transferred to a liquid, it can be removed from the datacenter efficiently. The transition from air to liquid cooling is an inflection point providing an opportunity to work collectively to set guidelines for facilitating the energy efficiency of liquid-cooled High Performance Computing (HPC) facilities and systems. The vision is to use non-compressor-based cooling, to facilitate heat re-use, and thereby build solutions that are more energy-efficient, less carbon intensive and more cost effective than their air-cooled predecessors. The Energy Efficient HPC Working Group is developing guidelines for warmer liquid-cooling temperatures in order to standardize facility and HPC equipment, and provide more opportunity for reuse of waste heat. This report describes the development of those guidelines.
Date: August 26, 2011
Creator: Corporation, IBM; Group, Energy Efficient HPC Working; Corporation, Hewlett Packard; SGI; Inc., Cray; Corporation, Intel et al.
Partner: UNT Libraries Government Documents Department

How People Actually Use Thermostats

Description: Residential thermostats have been a key element in controlling heating and cooling systems for over sixty years. However, today's modern programmable thermostats (PTs) are complicated and difficult for users to understand, leading to errors in operation and wasted energy. Four separate tests of usability were conducted in preparation for a larger study. These tests included personal interviews, an on-line survey, photographing actual thermostat settings, and measurements of ability to accomplish four tasks related to effective use of a PT. The interviews revealed that many occupants used the PT as an on-off switch and most demonstrated little knowledge of how to operate it. The on-line survey found that 89% of the respondents rarely or never used the PT to set a weekday or weekend program. The photographic survey (in low income homes) found that only 30% of the PTs were actually programmed. In the usability test, we found that we could quantify the difference in usability of two PTs as measured in time to accomplish tasks. Users accomplished the tasks in consistently shorter times with the touchscreen unit than with buttons. None of these studies are representative of the entire population of users but, together, they illustrate the importance of improving user interfaces in PTs.
Date: August 15, 2010
Creator: Meier, Alan; Aragon, Cecilia; Hurwitz, Becky; Mujumdar, Dhawal; Peffer, Therese; Perry, Daniel et al.
Partner: UNT Libraries Government Documents Department


Description: Low cost material is needed for grouting abandoned retorts. Experimental work has shown that a hydraulic cement can be produced from Lurgi spent shale by mixing it in a 1:1 weight ratio with limestone and heating one hour at 1000°C. With 5% added gypsum, strengths up to 25.8 MPa are obtained. This cement could make an economical addition up to about 10% to spent shale grout mixes, or be used in ordinary cement applications.
Date: June 1, 1980
Creator: Mehta, P.K.; Persoff, P. & Fox, J.P.
Partner: UNT Libraries Government Documents Department

Future Roles of Milli-, Micro-, and Nano- Grids

Description: Although it has slowed considerably, consumption of electricity continues to grow in developed economies. Further, there are some unknowns which might accelerate this growth, such as electrification of vehicle fleets and geothermal heat pump space and water heating. Most analysts anticipate that distributed energy resources (DER) will provide a large share of the expanded generation capacity required to meet this seemingly inexorably increasing electricity demand. Further, given the urgency of tackling the climate change problem, most of the added assets must be carbonfree renewables or nuclear, end-use efficiency improvements, or highly efficient fossil-fired technologies. In developed economies worldwide, the current power delivery paradigm has been in place for more than a century, i.e. since the emergence of polyphase AC systems around the turn of the last century. A key feature of this structure is that, in principle, universal service is delivered at a consistent level of power quality and reliability (PQR) throughout large regions. This paper describes a future possible structure for the electricity generation and delivery system that leaves the existing high voltage meshed grid paradigm in place, but involves radical reorganization of parts of the distribution network and customer sites. Managing a much more diverse dispersed system poses major challenges to the current centralized grid paradigm, particularly since many of these assets are small to tiny by macrogrid standards and they may ultimately number in the millions. They are also not ones that centralized control can rely upon to function in traditionally dependable ways, e.g. renewable generation can be highly variable and changes in output of generators are not independent. Although most involved in the industry agree that a paradigm shift is both necessary and desirable to manage the new system, the nature of the future system remains quite unclear. In the possible structure described here, the traditional ...
Date: July 1, 2011
Creator: Marnay, Chris; Nordman, Bruce & Lai, Judy
Partner: UNT Libraries Government Documents Department

Gas and Particulate Sampling of Airborne Polycyclic Aromatic Compounds

Description: The denuder surfaces of the gas and particle (GAP) sampler (developed at the Atmospheric Environment Service of Environment Canada) have been modified by coating with XAD-4 resin, using techniques developed at Lawrence Berkeley National Laboratory (LBNL) for the lower capacity integrated organic vapor/particle sampler (IOVPS). The resulting high capacity integrated organic gas and particle sampler (IOGAPS) has been operated in ambient air at 16.7 L min{sup -1} for a 24-hour period in Berkeley, California, USA. Simultaneous measurements were made at the same collection rate with a conventional sampler that used a filter followed by two sorbent beds. Gas and particle partition measurements were determined for 13 polycyclic aromatic hydrocarbons (PAH) ranging from 2-ring to 6-ring species. The IOGAPS indicated a higher particle fraction of these compounds than did the conventional sampler, suggesting that the conventional sampler suffered from 'blow-off' losses from the particles collected on the filter.
Date: October 1, 1995
Creator: Lane, D.A. & Gundel, L.A.
Partner: UNT Libraries Government Documents Department

Key Elements of and Materials Performance Targets for Highly Insulating Window Frames

Description: The thermal performance of windows is important for energy efficient buildings. Windows typically account for about 30-50 percent of the transmission losses though the building envelope, even if their area fraction of the envelope is far less. The reason for this can be found by comparing the thermal transmittance (U-factor) of windows to the U-factor of their opaque counterparts (wall, roof and floor constructions). In well insulated buildings the U-factor of walls, roofs an floors can be between 0.1-0.2 W/(m2K). The best windows have U-values of about 0.7-1.0. It is therefore obvious that the U-factor of windows needs to be reduced, even though looking at the whole energy balance for windows (i.e. solar gains minus transmission losses) makes the picture more complex.In high performance windows the frame design and material use is of utmost importance, as the frame performance is usually the limiting factor for reducing the total window U-factor further. This paper describes simulation studies analyzing the effects on frame and edge-of-glass U-factors of different surface emissivities as well as frame material and spacer conductivities. The goal of this work is to define materials research targets for window frame components that will result in better frame thermal performance than is exhibited by the best products available on the market today.
Date: March 28, 2011
Creator: Gustavsen, Arild; Grynning, Steinar; Arasteh, Dariush; Jelle, Bjorn Petter & Goudey, Howdy
Partner: UNT Libraries Government Documents Department


Description: Combustion-produced soot (carbonaceous) particles have been found to be efficient catalysts for SO{sub 2} oxidation, especially in the presence of liquid water. A kinetic study of the catalytic oxidation of SO{sub 2} on carbon particles suspended in solution has been carried out. The reaction was found to be first order with respect to the concentration of carbon particles, 0.69th order with respect to dissolved oxygen, between zero and second order with respect to S(IV) concentrations, and independent of the pH. Temperature studies were carried out, and an activation energy for this reaction was determined. A four-step mechanism is proposed for this carbon-catalyzed oxidation reaction.
Date: February 1, 1980
Creator: Brodzinsky, R.; Chang, S.G.; Markowitz, S.S. & Novakov, T.
Partner: UNT Libraries Government Documents Department

Laboratory measurement of secondary pollutant yields from ozone reaction with HVAC filters.

Description: We used Proton Transfer Reaction - Mass Spectrometry (PTR-MS) and conventional sampling methods to monitor and identify trace level organic pollutants formed in heterogeneous reactions between ozone and HVAC filters in real time. Experiments were carried out using a bench-scale flow tube reactor operating with dry air and humidified air (50% RH), at realistically high ozone concentrations (150 ppbv). We explored different filter media (i.e., fiberglass and cotton/polyester blends) and different particle loadings (i.e., clean filter and filters loaded with particles for 3 months at the Lawrence Berkeley National Laboratory and the Port of Oakland, CA). Detailed emission dynamics of very low levels of certain organic pollutants from filter media upon ozone exposure in the presence of moisture have been obtained and analyzed.
Date: September 9, 2009
Creator: Destaillats, Hugo; Chen, Wenhao; Apte, Michael; Li, Nuan; Spears, Michael; Almosni, Jérémie et al.
Partner: UNT Libraries Government Documents Department


Description: The relatively long lifetime of droplets in atmospheric haze and fog in comparison to similar droplets of pure water is attributed to the presence of a monolayer of surfactant film and to the accumulation of soluble salts from chemical reactions. The lifetime of these droplets is a significant factor in the evaluation of the role of heterogeneous aqueous chemical reactions occurring in the troposphere. A new formulation is given which includes both these processes. As an example, the catalytic oxidation of SO{sub 2} in the presence of liquid water droplets is investigated.
Date: September 1, 1980
Creator: Toossi, R. & Novakov, T.
Partner: UNT Libraries Government Documents Department


Description: This study describes the impact of lighting management systems that dynamically control lights in accordance with the needs of occupants. Various control strategies are described: scheduling, tuning, lumen depreciation, and daylighting. From initial experimental results, the energy savings provided by each of the above strategies are estimated to be 26, 12, 14, and 15%, respectively. Based upon a cost of $0.05-0.10 per kWh for electric energy and a 2-, 3-, or 4-yr payback, target costs for a simple and a sophisticated lighting management system are found to be $0.24 and 1.89 per ft{sup 2}, respectively, for a cost-effective investment. A growth model, based upon an extrapolation of the increase in building stock since 1975, indicates that the commercial and industrial (C and I) building stock will grow from 40 x 10{sup 9} ft{sup 2} in 1980 to about 67 x 10{sup 9} ft{sup 2} by the year 2000. Even with the use of more efficient lighting components, the energy required for this additional C and I stock will be 307 x 10{sup 9} kWh, an increase of only 13 x 10{sup 9} kWh above current use. The specified information is used to analyze the economic impacts that using these systems will have on the lighting industry, end users, utility companies, and the nation's economy. A $1 - 4 x 10{sup 9} annual lighting control industry can be generated, creating many jobs. The estimated return on investment (ROI) for controls for end users would be between 19 and 38%. Utilities will be able to make smaller additions to capacity and invest less capital at 7-10% ROI. Finally, the annual energy savings, up to $3.4 x 10{sup 9} for end users and about $5 x 10{sup 9} for utilities, representing unneeded generating capacity, will be available to capitalize other areas of the ...
Date: September 1, 1982
Creator: Verderber, R.R. & Rubinstein, F.
Partner: UNT Libraries Government Documents Department

Liquid-Water Uptake and Removal in PEM Fuel-Cell Components

Description: Management of liquid water is critical for optimal fuel-cell operation, especially at low temperatures. It is therefore important to understand the wetting properties and water holdup of the various fuel-cell layers. While the gas-diffusion layer is relatively hydrophobic and exhibits a strong intermediate wettability, the catalyst layer is predominantly hydrophilic. In addition, the water content of the ionomer in the catalyst layer is lower than that of the bulk membrane, and is affected by platinum surfaces. Liquid-water removal occurs through droplets on the surface of the gas-diffusion layer. In order to predict droplet instability and detachment, a force balance is used. While the pressure or drag force on the droplet can be derived, the adhesion or surface-tension force requires measurement using a sliding-angle approach. It is shown that droplets produced by forcing water through the gas-diffusion layer rather than placing them on top of it show much stronger adhesion forces owing to the contact to the subsurface water.
Date: September 23, 2011
Creator: Das, Prodip K.; Gunterman, Haluna P.; Kwong, Anthony & Weber, Adam Z.
Partner: UNT Libraries Government Documents Department

A Low Carbon Development Guide for Local Government Actions in China

Description: Local level actions are crucial for achieving energy-saving and greenhouse gas emission reduction targets. Yet it is challenging to implement new policies and actions due to a lack of information, funding, and capacity. This is particularly the case in developing countries such as China. Even though national energy intensity and carbon intensity targets have been set, most local governments do not have the knowledge regarding actions to achieve the targets, the cost-effectiveness of policies, the possible impact of policies, or how to design and implement a climate action plan. This paper describes a guidebook that was developed to motivate and provide local governments in China with information to create an action plan to tackle climate change and increase energy efficiency. It provides a simple step-by-step description of how action plans can be established and essential elements to be included - from preparing a GHG emission inventory to implementation of the plan. The guidebook also provides a comprehensive list of successful policies and best practices found internationally and in China to encourage low carbon development in industry, buildings, transportation, electric power generation, agriculture and forestry. This paper also presents indicators that can be used to define low-carbon development, as well as to evaluate the effectiveness of actions taken at an aggregated (city) level, and at a sectoral or end use level. The guidebook can also be used for low carbon development by local governments in other developing countries.
Date: May 1, 2011
Creator: Zheng, Nina; Zhou, Nan; Price, Lynn & Ohshita, Stephanie
Partner: UNT Libraries Government Documents Department

Max Tech Appliance Design: Potential for Maximizing U.S. Energy Savings through Standards

Description: This study surveyed the technical potential for efficiency improvements in 150 categories of appliances and equipment representing 33 quads of primary energy use across the US economy in 2010 and (1) documented efficient product designs, (2) identified the most promising cross-cutting strategies, and (3) ranked national energy savings potential by end use. Savings were estimated using a method modeled after US Department of Energy priority-setting reports - simplified versions of the full technical and economic analyses performed for rulemakings. This study demonstrates that large savings are possible by replacing products at the end-of-life with ultra-efficient models that use existing technology. Replacing the 50 top energy-saving end-uses (constituting 30 quads of primary energy consumption in 2010) with today's best-on-market equivalents would save {approx}200 quads of US primary energy over 30 years (25% of consumption anticipated there from). For the 29 products for maximum feasible savings potential could be estimated, the savings were twice as high. These results demonstrate that pushing ultra-efficient products to market could significantly escalate carbon emission reductions and is a viable strategy for sustaining large emissions reductions through standards. The results of this analysis were used by DOE for new coverage prioritization, to identify key opportunities for product prototyping and market development, and will leverage future standards rulemakings by identifying the full scope of maximum feasible technology options. High leverage products include advances lighting systems, HVAC, and televisions. High leverage technologies include electronic lighting, heat pumps, variable speed motors, and a host of controls-related technologies.
Date: May 6, 2011
Creator: Garbesi, Karina; Desroches, Louis-Benoit; Bolduc, Christopher; Burch, Gabriel; Hosseinzadeh, Griffin & Saltiel, Seth
Partner: UNT Libraries Government Documents Department


Description: The purpose of this project is to provide measurements and analyses of the solar and circumsolar radiation for application to solar energy systems that employ lenses or mirrors to concentrate the incident sunlight. Circumsolar radiation results from the scattering of direct sunlight through small angles by atmospheric aerosols (e.g., dust, water-droplets or ice crystals in thin clouds). Concentrating solar energy systems will typically collect all of the direct solar radiation (that originating from the disk of the sun) plus some fraction of the circumsolar radiation. The exact fraction depends upon many factors, but primarily upon the angular size (field-of-view) of the receiver. A knowledge of the circumsolar radiation is then one factor in predicting or evaluating the performance of concentrating systems. The project employs unique instrument systems (called Circumsolar Telescopes) that were designed and fabricated at LBL. The basic measurements are (1) the "circumsolar scan", the brightness of the sun and circumsolar region as a function of angular distance from the center of the sun and (2) the usual "normal incidence" measurement of a pyrheliometer. Both measurements are made for the entire solar spectrum, and (via colored filters) for eight essentially contiguous wavelength bands. Thus the measurements are applicable to systems in which the receiver is essentially wavelength-insensitive (e.g., central receiver) and to wavelength-sensitive systems (e.g., concentrating photovoltaics). A secondary purpose of the project is to relate the data to the atmospheric processes that attenuate the solar radiation available to terrestrial solar energy systems.
Date: October 1, 1980
Creator: Grether, Donald; Evans, David; Hunt, Arlon & Wahlig, Michael
Partner: UNT Libraries Government Documents Department