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Comparative evaluation of the impacts of domestic gas and electric heat pump heating on air pollution in California. Final report

Description: Residential space and water heating accounts for approximately 12% of California`s and 15% of the United States, energy consumption. most Of the residential heating is by direct use of natural gas. combustion of natural gas is a contributor to the overall air pollution,, especially CO and NO{sub x} in the urban areas. Another efficient method for domestic water and space heating is use of electric heat pumps, the most popular category of which uses air as its heat source. Electric heat pumps do not emit air pollutants at the point of use, but use electric power, which is a major contributor to air pollution at its point of generation from fossil fuels. It is the specific objective of this report to evaluate and compare the energy efficiency and source air pollutants of natural gas heaters and electric heat pumps used for domestic heating. Effect of replacing natural gas heaters with electric heat pumps on air pollutant emissions due to domestic heating in two urban areas and in California as a whole has also been evaluated. The analysis shows that with the present state of technology, electric heat pumps have higher heating efficiencies than natural gas heaters. Considering the current electricity generation mix in the US, electric heat pumps produce two to four times more NO{sub x}, much less CO, and comparable amount of CO{sub 2} per unit of useful heating energy compared to natural gas heaters. With California mix, electric heat pumps produce comparable NO{sub x} and much less CO and approximately 30% less CO{sub 2} per unit heat output. Replacement of natural gas heaters with electric heat pumps will slightly increase the overall NO{sub x}, and reduce CO and CO{sub 2} emissions in California. The effect of advanced technology power generation and heat pump heating has also been analyzed.
Date: July 1, 1992
Creator: Ganji, A.
Partner: UNT Libraries Government Documents Department

Energy efficiency and the environment: Innovative ways to improve air quality in the Los Angeles Basin

Description: This paper focuses on novel, innovative approaches for reducing or delaying the production of photochemical smog in the Los Angeles Basin. These approaches include modifying the surface characteristics of the basin by increasing surface albedo and an extensive tree-planting program. The changes in surface conditions are designed to reduce the basin air temperatures, especially during the summer months, which will result in two possible effects. First, a decrease in temperature would lead to a reduction in energy use with an associated decline in emissions of nitrogen oxides (NO{sub x}) and a lowering of evaporative emission of reactive organic gases. Reductions in these smog precursors could improve the air quality of the basin without imposing additional emissions regulations. The second effect is associated with the possible causal relationship between air temperature and smog formation (i.e., lower temperatures and lower incidence of smog). Since this approach to mitigating air emissions is broad, the studies to date have concentrated on how changes in surface characteristics affect the meteorological conditions of the basin and on how these meteorological changes subsequently affect smog production. A geographic information system database of key surface characteristics (i.e., vegetative cover, albedo, moisture availability, and roughness) was compiled, and these characteristics were evaluated using prognostic meteorological models. The results of two- and three-dimensional meteorological simulations will be presented and discussed in this paper.
Date: February 1, 1993
Creator: Ritschard, R.
Partner: UNT Libraries Government Documents Department

Energy efficiency and the environment: Innovative ways to improve air quality in the Los Angeles Basin

Description: This paper focuses on novel, innovative approaches for reducing or delaying the production of photochemical smog in the Los Angeles Basin. These approaches include modifying the surface characteristics of the basin by increasing surface albedo and an extensive tree-planting program. The changes in surface conditions are designed to reduce the basin air temperatures, especially during the summer months, which will result in two possible effects. First, a decrease in temperature would lead to a reduction in energy use with an associated decline in emissions of nitrogen oxides (NO[sub x]) and a lowering of evaporative emission of reactive organic gases. Reductions in these smog precursors could improve the air quality of the basin without imposing additional emissions regulations. The second effect is associated with the possible causal relationship between air temperature and smog formation (i.e., lower temperatures and lower incidence of smog). Since this approach to mitigating air emissions is broad, the studies to date have concentrated on how changes in surface characteristics affect the meteorological conditions of the basin and on how these meteorological changes subsequently affect smog production. A geographic information system database of key surface characteristics (i.e., vegetative cover, albedo, moisture availability, and roughness) was compiled, and these characteristics were evaluated using prognostic meteorological models. The results of two- and three-dimensional meteorological simulations will be presented and discussed in this paper.
Date: February 1, 1993
Creator: Ritschard, R.
Partner: UNT Libraries Government Documents Department

Energy efficiency in California laboratory-type facilities

Description: The central aim of this project is to provide knowledge and tools for increasing the energy efficiency and performance of new and existing laboratory-type facilities in California. We approach the task along three avenues: (1) identification of current energy use and savings potential, (2) development of a {ital Design guide for energy- Efficient Research Laboratories}, and (3) development of a research agenda for focused technology development and improving out understanding of the market. Laboratory-type facilities use a considerable amount of energy resources. They are also important to the local and state economy, and energy costs are a factor in the overall competitiveness of industries utilizing laboratory-type facilities. Although the potential for energy savings is considerable, improving energy efficiency in laboratory-type facilities is no easy task, and there are many formidable barriers to improving energy efficiency in these specialized facilities. Insufficient motivation for individual stake holders to invest in improving energy efficiency using existing technologies as well as conducting related R&D is indicative of the ``public goods`` nature of the opportunity to achieve energy savings in this sector. Due to demanding environmental control requirements and specialized processes, laboratory-type facilities epitomize the important intersection between energy demands in the buildings sector and the industrial sector. Moreover, given the high importance and value of the activities conducted in laboratory-type facilities, they represent one of the most powerful contexts in which energy efficiency improvements stand to yield abundant non-energy benefits if properly applied.
Date: July 31, 1996
Creator: Mills, E.; Bell, G. & Sartor, D.
Partner: UNT Libraries Government Documents Department

Analysis of climatic conditions and preliminary assessment of alternative cooling strategies for houses in California transition climate zones

Description: This is a preliminary scoping study done as part of the {open_quotes}Alternatives to Compressive Cooling in California Transition Climates{close_quotes} project, which has the goal of demonstrating that houses in the transitional areas between the coast and the Central Valley of California do not require air-conditioning if they are properly designed and operated. The first part of this report analyzes the climate conditions within the transitional areas, with emphasis on design rather than seasonal conditions. Transitional climates are found to be milder but more variable than those further inland. The design temperatures under the most stringent design criteria, e.g. 0.1 % annual, are similar to those in the Valley, but significantly lower under more relaxed design criteria, e.g., 2% annual frequency. Transition climates also have large day-night temperature swings, indicating significant potential for night cooling, and wet-bulb depressions in excess of 25 F, indicating good potential for evaporative cooling. The second part of the report is a preliminary assessment using DOE-2 computer simulations of the effectiveness of alternative cooling and control strategies in improving indoor comfort conditions in two conventional Title-24 houses modeled in various transition climate locations. The cooling measures studied include increased insulation, light colors, low-emissivity glazing, window overhangs, and exposed floor slab. The control strategies studied include natural and mechanical ventilation, and direct and two-stage evaporative cooling. The results indicate the cooling strategies all have limited effectiveness, and need to be combined to produce significant improvements in indoor comfort. Natural and forced ventilation provide similar improvements in indoor conditions, but during peak cooling periods, these will still be above the comfort zone. Two-stage evaporative coolers can maintain indoor comfort at all hours, but not so direct evaporative coolers.
Date: July 1, 1995
Creator: Huang, Y.J. & Zhang, H.
Partner: UNT Libraries Government Documents Department

Comparison of DOE-2 with measurements in the Pala Test houses

Description: The predictions of the DOE-2 program for building energy analysis have been compared with measurements in the Pala test houses near San Diego. This work is part of the California Institute for Energy Efficiency {open_quotes}Alternatives to Compressor Cooling in California Transition Zones{close_quotes} project in which DOE-2 is being used for parametric analysis of cooling strategies that reduce peak electrical power in hot, dry climates. To establish the validity of DOE-2 for this kind of analysis the program was compared with room air temperature measurements in a {open_quotes}low-mass{close_quotes} house with conventional insulated study wall construction and a {open_quotes}high-mass{close_quotes} house with insulated concrete walls. To test different aspects of the DOE-2 calculation, four different unconditioned thermal configurations of these houses were considered: unshaded windows, shaded windows, white exterior surfaces, and forced night ventilation. In all cases DOE-2 agreed well with the air temperature measurements, with a mean deviation between simulation and measurement ranging from 0.2 to 1.0 K depending on configuration and type of house. Using a development version of DOE-2 comparisons with inside surface temperature measurements were also made. These comparisons also showed good agreement.
Date: July 1995
Creator: Meldem, R. & Winkelmann, F.
Partner: UNT Libraries Government Documents Department

Numerical simulation of cold flow patterns and turbulent mixing in a simplified burner

Description: The COYOTE computer program was used to simulate the flow field and turbulent mixing near the fuel and air inlets in a simplified burner. The authors report the results of four cold flow calculations that illustrate several interesting phenomena in addition to demonstrating the capabilities of the basic hydrodynamics model and the turbulence model. They also demonstrate some interesting facets of the hydrodynamics of burners. They summarize their findings as follows: (1) two different grids gave vastly different answers, underscoring the importance of assuring grid-independence in numerical solutions; (2) cold flow patterns are much different than reactive flow fields, making it unwise to apply conclusions from the former to the latter; (3) the problem is elliptic, and it is necessary to include the whole furnace in the calculations; (4) the flow patterns exhibited weakly unstable, almost metastable, modes that make it difficult to ascertain when steady conditions have been obtained. The long range goals of this study are to identify parameters that affect the production of NO{sub x} and to discover methods of reducing emissions while maintaining or improving burner efficiency.
Date: October 1, 1994
Creator: Cloutman, L.D.
Partner: UNT Libraries Government Documents Department

Analysis of energy use in building services of the industrial sector in California: Two case studies

Description: Energy-use patterns in many of California's fastest-growing industries are not typical of the existing mix of industries in the US. Many California firms operate small- and medium-sized facilities housed in buildings used simultaneously or interchangeably over time for commercial (office, retail, warehouse) and industrial activities. In these industrial subsectors, the energy required for building services (providing occupant comfort and necessities like lighting, HVAC, office equipment, computers, etc.) may be at least as important as the more familiar process energy requirements -- especially for electricity and on-peak demand. Electricity for building services is sometimes priced as if it were base loaded like process uses; in reality this load varies significantly according to occupancy schedules and cooling and heating loads, much as in any commercial building. Using informal field surveys, simulation studies, and detailed analyses of existing data (including utility commercial/industrial audit files), we studied the energy use of this industrial subsector through a multi-step procedure: (1) characterizing non-process building energy and power use in California industries, (2) identifying conservation and load-shaping opportunities in industrial building services, and (3) investigating industrial buildings and system design methodologies. In an earlier report, we addressed these issues by performing an extensive survey of the existing publicly available data, characterizing and comparing the building energy use in this sector. In this report, we address the above objectives by examining and analyzing energy use in two industrial case-study facilities in California. Based on the information for the case studies, we discuss the design consideration for these industrial buildings, characterize their energy use, and review their conservation and load-shaping potentials. In addition, we identify and discuss some research ideas for further investigation.
Date: September 1, 1991
Creator: Akbari, H. & Sezgen, O.
Partner: UNT Libraries Government Documents Department

High-albedo materials for reducing building cooling energy use

Description: One simple and effective way to mitigate urban heat islands, i.e., the higher temperatures in cities compared to those of the surrounds, and their negative impacts on cooling energy consumption is to use high-albedo materials on major urban surfaces such as rooftops, streets, sidewalks, school yards, and the exposed surfaces of parking lots. High-albedo materials can save cooling energy use by directly reducing the heat gain through a building's envelope (direct effect) and also by lowering the urban air temperature in the neighborhood of the building (indirect effect). This project is an attempt to address high-albedo materials for buildings and to perform measurements of roof coatings. We search for existing methods and materials to implement fighter colors on major building and urban surfaces. Their cost effectiveness are examined and the possible related technical, maintenance, and environmental problems are identified. We develop a method for measuring albedo in the field by studying the instrumentation aspects of such measurements. The surface temperature impacts of various albedo/materials in the actual outdoor environment are studied by measuring the surface temperatures of a variety of materials tested on an actual roof. We also generate an albedo database for several urban surfaces to serve as a reference for future use. The results indicate that high-albedo materials can have a large impact on the surface temperature regime. On clear sunny days, when the solar noon surface temperatures of conventional roofing materials were about 40{degrees}C (72{degrees}F) warmer than air, the surface temperature of high-albedo coatings were only about 5{degrees}C warmer than air. In the morning and in the late afternoon, the high-albedo materials were as cool as the air itself. While conventional roofing materials warm up by an average 0.055{degrees}C/(W m{sup {minus}2}), the high-albedo surfaces warm up by an average 0.015{degrees}C/(W m{sup {minus}2}).
Date: January 1, 1992
Creator: Taha, H.; Sailor, D. & Akbari, H.
Partner: UNT Libraries Government Documents Department

Research and Development Conference CIEE Program 1992

Description: CIEE`s second annual Research and Development Conference will introduce you to some of the results achieved to date through CIEE-sponsored multiyear research performed in three programs: Building Energy Efficiency, Air Quality Impacts of Energy Efficiency, and End-Use Resource Planning. Results from scoping studies, Director`s discretionary research, and exploratory research will also be featured in this report.
Date: November 1, 1992
Partner: UNT Libraries Government Documents Department

Cost-effectiveness of controlling emissions for various alternative-fuel vehicle types, with vehicle and fuel price subsidies estimated on the basis of monetary values of emission reductions

Description: Emission-control cost-effectiveness is estimated for ten alternative-fuel vehicle (AFV) types (i.e., vehicles fueled with reformulated gasoline, M85 flexible-fuel vehicles [FFVs], M100 FFVs, dedicated M85 vehicles, dedicated M100 vehicles, E85 FFVS, dual-fuel liquefied petroleum gas vehicles, dual-fuel compressed natural gas vehicles [CNGVs], dedicated CNGVs, and electric vehicles [EVs]). Given the assumptions made, CNGVs are found to be most cost-effective in controlling emissions and E85 FFVs to be least cost-effective, with the other vehicle types falling between these two. AFV cost-effectiveness is further calculated for various cases representing changes in costs of vehicles and fuels, AFV emission reductions, and baseline gasoline vehicle emissions, among other factors. Changes in these parameters can change cost-effectiveness dramatically. However, the rank of the ten AFV types according to their cost-effectiveness remains essentially unchanged. Based on assumed dollars-per-ton emission values and estimated AFV emission reductions, the per-vehicle monetary value of emission reductions is calculated for each AFV type. Calculated emission reduction values ranged from as little as $500 to as much as $40,000 per vehicle, depending on AFV type, dollar-per-ton emission values, and baseline gasoline vehicle emissions. Among the ten vehicle types, vehicles fueled with reformulated gasoline have the lowest per-vehicle value, while EVs have the highest per-vehicle value, reflecting the magnitude of emission reductions by these vehicle types. To translate the calculated per-vehicle emission reduction values to individual AFV users, AFV fuel or vehicle price subsidies are designed to be equal to AFV emission reduction values. The subsidies designed in this way are substantial. In fact, providing the subsidies to AFVs would change most AFV types from net cost increases to net cost decreases, relative to conventional gasoline vehicles.
Date: December 31, 1993
Creator: Wang, M. Q.
Partner: UNT Libraries Government Documents Department

Implementation of solar-reflective surfaces: Materials and utility programs

Description: This report focuses on implementation issues for using solar-reflective surfaces to cool urban heat islands, with specific examples for Sacramento, California. Advantages of solar-reflective surfaces for reducing energy use are: (1) they are cost-effective if albedo is increased during routine maintenance; (2) the energy savings coincide with peak demand for power; (3) there are positive effects on environmental quality; and (4) the white materials have a long service life. Important considerations when choosing materials for mitigating heat islands are identified as albedo, emissivity, durability, cost, pollution and appearance. There is a potential for increasing urban albedo in Sacramento by an additional 18%. Of residential roofs, we estimate that asphalt shingle and modified bitumen cover the largest area, and that built-up roofing and modified bitumen cover the largest area of commercial buildings. For all of these roof types, albedo may be increased at the time of re-roofing without any additional cost. When a roof is repaired, a solar-reflective roof coating may be applied to significantly increase albedo and extend the life of the root Although a coating may be cost-effective if applied to a new roof following installation or to an older roof following repair, it is not cost-effective if the coating is applied only to save energy. Solar-reflective pavement may be cost-effective if the albedo change is included in the routine resurfacing schedule. Cost-effective options for producing light-colored pavement may include: (1) asphalt concrete, if white aggregate is locally available; (2) concrete overlays; and (3) newly developed white binders and aggregate. Another option may be hot-rolled asphalt, with white chippings. Utilities could promote solar-reflective surfaces through advertisement, educational programs and cost-sharing of road resurfacing.
Date: June 1, 1992
Creator: Bretz, S.; Akbari, H.; Rosenfeld, A. & Taha, H.
Partner: UNT Libraries Government Documents Department

Case studies of thermal energy storage (TES) systems: Evaluation and verification of system performance. Final report

Description: We have developed two case studies to review and analyze energy performance of thermal energy storage CMS systems in commercial buildings. Our case studies considered two partial ice storage systems in Northern California. For each case, we compiled historical data on TES design, installation, and operation. This information was further enhanced by data obtained through interviews with the building owners and operators. The performance and historical data of the TES systems and their components were grouped into issues related to design, installation, operation, and maintenance of the systems. Our analysis indicated that (1) almost all problems related to the operation of TES and non-TES systems could be traced back to the design of the system, and (2) the identified problems were not unique to the TES systems. There were as many original problems with ``conventional`` HVAC systems and components as with TES systems. Judging from the problems related to non-TES components identified in these two case studies, it is reasonable to conclude that conventional systems have as many problems as TES systems, but a failure, in a TES system may have a more dramatic impact on thermal comfort and electricity charges. The objective of the designers of the TES systems in the case-study buildings was to design just-the-right-size systems so that both the initial investment and operating costs would be minimized. Given such criteria, a system is typically designed only for normal and steady-state operating conditions-which often precludes due consideration to factors such as maintenance, growth in the needed capacity, ease of the operation, and modularity of the systems. Therefore, it is not surprising to find that these systems, at least initially, did not perform to the design intent and expectation and that they had to go through extended periods of trouble-shooting.
Date: January 1, 1992
Creator: Akbari, H. & Sezgen, O.
Partner: UNT Libraries Government Documents Department

High-albedo materials for reducing building cooling energy use

Description: One simple and effective way to mitigate urban heat islands, i.e., the higher temperatures in cities compared to those of the surrounds, and their negative impacts on cooling energy consumption is to use high-albedo materials on major urban surfaces such as rooftops, streets, sidewalks, school yards, and the exposed surfaces of parking lots. High-albedo materials can save cooling energy use by directly reducing the heat gain through a building`s envelope (direct effect) and also by lowering the urban air temperature in the neighborhood of the building (indirect effect). This project is an attempt to address high-albedo materials for buildings and to perform measurements of roof coatings. We search for existing methods and materials to implement fighter colors on major building and urban surfaces. Their cost effectiveness are examined and the possible related technical, maintenance, and environmental problems are identified. We develop a method for measuring albedo in the field by studying the instrumentation aspects of such measurements. The surface temperature impacts of various albedo/materials in the actual outdoor environment are studied by measuring the surface temperatures of a variety of materials tested on an actual roof. We also generate an albedo database for several urban surfaces to serve as a reference for future use. The results indicate that high-albedo materials can have a large impact on the surface temperature regime. On clear sunny days, when the solar noon surface temperatures of conventional roofing materials were about 40{degrees}C (72{degrees}F) warmer than air, the surface temperature of high-albedo coatings were only about 5{degrees}C warmer than air. In the morning and in the late afternoon, the high-albedo materials were as cool as the air itself. While conventional roofing materials warm up by an average 0.055{degrees}C/(W m{sup {minus}2}), the high-albedo surfaces warm up by an average 0.015{degrees}C/(W m{sup {minus}2}).
Date: January 1, 1992
Creator: Taha, H.; Sailor, D. & Akbari, H.
Partner: UNT Libraries Government Documents Department

Hydronic radiant cooling: Overview and preliminary performance assessment

Description: A significant amount of electrical energy used to cool non-residential buildings is drawn by the fans used to transport the cool air through the thermal distribution system. Hydronic systems reduce the amount of air transported through the building by separating ventilation and thermal conditioning. Due to the physical properties of water, hydronic distribution systems can transport a given amount of thermal energy using less than 5% of the otherwise necessary fan energy. This savings alone significantly reduces the energy consumption and especially the peak power requirement This survey clearly shows advantages for radiant cooling in combination with hydronic thermal distribution systems in comparison with the All-Air Systems commonly used in California. The report describes a literature survey on the system`s development, thermal comfort issues, and cooling performance. The cooling power potential and the cooling power requirement are investigated for several California climates. Peak-power requirement is compared for hydronic radiant cooling and conventional All-Air-Systems.
Date: May 1, 1993
Creator: Feustel, H. E.
Partner: UNT Libraries Government Documents Department

Analysis of energy use in building services of the industrial sector in California: Two case studies. Final report

Description: Energy-use patterns in many of California`s fastest-growing industries are not typical of the existing mix of industries in the US. Many California firms operate small- and medium-sized facilities housed in buildings used simultaneously or interchangeably over time for commercial (office, retail, warehouse) and industrial activities. In these industrial subsectors, the energy required for building services (providing occupant comfort and necessities like lighting, HVAC, office equipment, computers, etc.) may be at least as important as the more familiar process energy requirements -- especially for electricity and on-peak demand. Electricity for building services is sometimes priced as if it were base loaded like process uses; in reality this load varies significantly according to occupancy schedules and cooling and heating loads, much as in any commercial building. Using informal field surveys, simulation studies, and detailed analyses of existing data (including utility commercial/industrial audit files), we studied the energy use of this industrial subsector through a multi-step procedure: (1) characterizing non-process building energy and power use in California industries, (2) identifying conservation and load-shaping opportunities in industrial building services, and (3) investigating industrial buildings and system design methodologies. In an earlier report, we addressed these issues by performing an extensive survey of the existing publicly available data, characterizing and comparing the building energy use in this sector. In this report, we address the above objectives by examining and analyzing energy use in two industrial case-study facilities in California. Based on the information for the case studies, we discuss the design consideration for these industrial buildings, characterize their energy use, and review their conservation and load-shaping potentials. In addition, we identify and discuss some research ideas for further investigation.
Date: September 1, 1991
Creator: Akbari, H. & Sezgen, O.
Partner: UNT Libraries Government Documents Department

Optional time-of-use prices for electricity: Analysis of PG&E`s experimental TOU rates. Final report

Description: We examine customers` time-of-use (TOU) demand for electricity and their choice between standard and TOU rate schedules. We specify an econometric model in which the customer`s demand curves determine the customer`s choice of rate schedule. We estimate the model on data from Pacific Gas & Electric Company`s experiment with optional TOU prices in the residential sector. With the model, we compare the TOU consumption and price elasticities of customers who chose TOU rates with those who chose standard rates. We also estimate the impact of the TOU rates on the utility`s revenues and costs. The analysis suggests that the TOU rates offered under PG&E`s experiment decreased PG&E`s profits and hence contributed to higher general rate levels. The model can be used, however, to design optional TOU rates that increase profits and lower general rate levels.
Date: July 1, 1992
Creator: Train, K. & Mehrez, G.
Partner: UNT Libraries Government Documents Department

Numerical simulation of turbulent mixing and combustion near the inlet of a burner

Description: The COYOTE computer program was used to simulate the flow field and turbulent mixing near the fuel and air inlets in a simplified burner that was proposed for experimental study at the Combustion Laboratory at the University of California at Irvine. Four cases are presented, with and without chemical reactions, with two different outflow boundary conditions, and with two different swirl numbers. These preliminary results demonstrate the ability of COYOTE to simulate burners, and they illustrate some limitations and requirements of such modeling.
Date: February 1, 1993
Creator: Cloutman, L. D.
Partner: UNT Libraries Government Documents Department

Advanced monitoring technologies for the evaluation of demand-side management programs

Description: This report was commissioned by the California Institute for Energy Efficiency as part of its research mission to advance the energy efficiency and productivity of all end-use sectors in California. The aim of this study is to provide an assessment of the state-of-the-art technologies that can be used for monitoring and evaluating demand-side management (DSM) programs. Additionally, the study points out research, development, and demonstration projects whose implementation can contribute to a more accurate and cost-effective evaluation of the performance of end-use technologies. During the past two decades, technology developments in the fields of microelectronics, computers and communications had a large impact on monitoring equipment. The improvements achieved led to the appearance of increasingly powerful, convenient to use, and flexible equipment, enabling a wider application of end-use metering at a lower cost. Equipment specifications are getting closer and closer to an ``ideal`` monitoring system: Good accuracy, high reliability, moderate cost, large number of monitored end uses, large data storage capacity, flexible communications, non-intrusiveness, powerful preprocessing of data. This report briefly examines the following techniques that can be used for end-use monitoring: field test equipment, general purpose data loggers, run-time data loggers, utility-oriented data loggers, energy management systems, two-way communication, power line carrier techniques, direct and distributed load control, and non-intrusive load monitoring. The report concludes with recommendations for developing new measurement technologies, as well as additional research and development activities to support these efforts.
Date: June 1, 1993
Creator: De Almeida, A. T. & Vine, E. L.
Partner: UNT Libraries Government Documents Department

Role of surface characteristics in urban meteorology and air quality

Description: Urbanization results in a landscape with significantly modified surface characteristics. The lower values of reflectivity to solar radiation, surface moisture availability, and vegetative cover, along with the higher values of anthropogenic heat release and surface roughness combine to result higher air temperatures in urban areas relative to their rural counterparts. Through their role in the surface energy balance and surface exchange processes, these surface characteristics are capable of modifying the local meteorology. The impacts on wind speeds, air temperatures, and mixing heights are of particular importance, as they have significant implications in terms of urban energy use and air quality. This research presents several major improvements to the meteorological modeling methodology for highly heterogeneous terrain. A land-use data-base is implemented to provide accurate specification of surface characteristic variability in simulations of the Los Angeles Basin. Several vegetation parameterizations are developed and implemented, and a method for including anthropogenic heat release into the model physics is presented. These modeling advancements are then used in a series of three-dimensional simulations which were developed to investigate the potential meteorological impact of several mitigation strategies. Results indicate that application of moderate tree-planting and urban-lightening programs in Los Angeles may produce summertime air temperature reductions on the order of 4{degree}C with a concomitant reduction in air pollution. The analysis also reveals several mechanisms whereby the application of these mitigation strategies may potentially increase pollutant concentrations. The pollution and energy use consequences are discussed in detail.
Date: August 1, 1993
Creator: Sailor, D. J.
Partner: UNT Libraries Government Documents Department

The California Institute for Energy Efficiency multiyear research plan, 1992--1996

Description: The mission of the California Institute for Energy Efficiency (CIEE) is to coordinate, plan, and implement a statewide program of medium- to long-term (five to fifteen years) applied research aimed at advancing the energy efficiency and productivity of all end-use sectors in California. The focus of CIEE`s multiyear research and development (R&D) program is to benefit California`s ratepayers within the context of the state`s energy, environmental, and economic needs and priorities. This context includes the current research efforts of CIEE`s sponsors, of significant national R&D organizations, and of industry. CIEE`s 1992--1996 Multiyear Research Plan guides the Institute`s research development, research management, and technology transfer efforts. The Plan briefly describes CIEE`s current R&D program and introduces potential R&D initiatives that are responsive to California`s unmet energy efficiency needs. In 1992, CIEE is planning, funding, and managing $5 million in multiyear research, exploratory research, Director`s discretionary research, and technology transfer activities. The Institute`s 1992 effort includes $3.6 million in multiyear research conducted in the Building Energy Efficiency, Air Quality Impacts of Energy Efficiency, and End-Use Resource Planning programs and $1 million in exploratory and Director`s discretionary research. During the period 1992 to 1996, CIEE will continue to conduct energy efficiency R&D that will secure sustainable, affordable energy for California while improving the state`s economy and environment.
Date: July 1, 1992
Partner: UNT Libraries Government Documents Department

Improved modelling of HVAC system/envelope inteactions in residential buildings

Description: General building energy simulation programs do not typically simulate interactions between HVAC systems and building envelopes. For this reason, a simulation tool which includes interactions between duct systems, building envelopes, and heating and cooling appliances in residential buildings has been developed. The simulation tool uses DOE- 2 (to model space conditioning loads and zone temperatures), COMIS (an airflow network solver), and a model of duct leakage and conduction losses. Three augmentations to the simulation tool are presented herein, along with sample results. These include: (1) modeling of steady-state thermosiphon flows in ducts, (2) improved simplified modeling of duct thermal mass effects, and (3) modeling of multi-speed space conditioning equipment. Multi-speed air conditioners are shown to be more sensitive to duct efficiency than single-speed equipment, because their efficiency decreases with increasing cooling load. Thermosiphon flows through duct systems are estimated to be 5-16% of the total heating load, depending on the duct insulation level. The duct dynamics model indicates that duct thermal mass decreases the energy delivery efficiency of the distribution system by 1-6 percentage points.
Date: March 1, 1995
Creator: Modera, M.P. & Treidler, B.
Partner: UNT Libraries Government Documents Department

Energy efficiency improvements for refrigerator/freezers using prototype doors containing gas-filled panel insulating systems

Description: Energy efficiency improvements in domestic refrigerator/freezers, are directly influenced by the overall thermal performance of the cabinet and doors. An advanced system for reducing heat gain is Gas-Filled Panel thermal insulation technology. Gas-Filled Panels contain a low-conductivity, inert gas at atmospheric pressure and employ a reflective baffle to suppress radiation and convection within the gas. This paper presents energy use test results for a 1993 model 500 liter top mount refrigerator/freezer operated with its original doors and with a series of alternative prototype doors. Gas-Filled Panel technology was used in two types of prototype refrigerator/freezer doors. In one design, panels were used in composite with foam in standard metal door pans; this design yielded no measurable energy savings. In the other design, special polymer door pans were fitted with panels that fill nearly all of the available insulation volume; this design yielded a 6.5% increase in energy efficiency for the entire refrigerator/freezer. The EPA Refrigerator Analysis computer program has been used to predict the change in daily energy consumption with the alternative doors. The computer model also projects a 25% energy efficiency improvement for a refrigerator/freezer that would use Gas-Filled Panel insulation throughout the cabinet as well as the doors.
Date: January 1, 1995
Creator: Griffith, B.; Arasteh, D. & Tuerler, D.
Partner: UNT Libraries Government Documents Department

Development of a model to simulate the performance of hydronic radiant cooling ceilings

Description: A significant amount of the electrical energy used to cool non-residential buildings equipped with all-air systems is drawn by the fans that transport the cool air through the thermal distribution system. Hydronic radiant cooling systems have the potential to reduce the amount of air transported through the building by separating the tasks of ventilation and thermal conditioning. Because of the physical properties of water, hydronic radiant cooling systems can transport a given amount of thermal energy using less than 5170 of the otherwise necessary fan energy. This improvement alone significantly reduces the energy consumption and peak power requirement of the air conditioning system. Hydronic radiant cooling systems have been used for more than 30 years in hospital rooms to provide a draft-free, thermally stable environment. The energy savings and peak-load characteristics of these systems have not yet been analyzed systematically. Moreover, adequate guidelines for design and control of these systems do not exist. This has prevented their widespread application to other building types. The evaluation of the theoretical performance of hydronic systems could be made most conveniently by computer models. Energy analysis programs such as DOE-2 do not have the capability to simulate hydronic radiant systems yet. In this paper the development of a model that can simulate accurately the dynamic performance of hydronic radiant cooling systems is described. The model is able to calculate loads, heat extraction rates, room air temperature and room surface temperature distributions, and can be used to evaluate issues such as thermal comfort, controls, system sizing, system configuration and dynamic response. The model was created with the Simulation Problem Analysis and Research Kernel (SPARK) developed at the Lawrence Berkeley Laboratory, which provides a methodology for describing and solving the dynamic, non-linear equations that correspond to complex physical systems.
Date: June 1, 1995
Creator: Stetiu, C. & Feustel, H.E.
Partner: UNT Libraries Government Documents Department