John F. Busch

A tale of two populations: thermal comfort in air-conditioned and naturally ventilated offices in Thailand

Abstract A field study of thermal comfort was conducted in Bangkok, Thailand, in which over 1100 office workers responded to a questionnaire while simultaneous physical measurements were taken. In this study we explore whether there is justification for adopting a comfort standard that differs from those developed for office workers accustomed to more temperate climates. Both air-conditioned and naturally ventilated offices were surveyed. Participants cast votes on standard subjective thermal rating scales and these were correlated with temperature indices that variously account for the thermal impacts of humidity, radiant temperature, air velocity, and clothing levels. Following the criteria used in developing a widely adopted thermal comfort standard, it was found that the upper temperature bound for a Thai comfort standard, instead of being the currently accepted level of 26.1 °C for those accustomed to air-conditioning accustomed to naturally ventilated spaces, and as high as 28 °C for those accustomed to air-conditioning. Comparing the responses from the naturally ventilated buildings with both those from the air-conditioned buildings and from studies conducted in the temperate regions provides convincing evidence of acclimatization. These and other findings of this study suggest that interior spaces in Thailand can be cooled to a far lesser degree without sacrificing comfort.

After-hours power status of office equipment and energy use of miscellaneous plug-load equipment

This research was conducted in support of two branches of the EPA ENERGY STAR program, whose overall goal is to reduce, through voluntary market-based means, the amount of carbon dioxide emitted in the U.S. The primary objective was to collect data for the ENERGY STAR Office Equipment program on the after-hours power state of computers, monitors, printers, copiers, scanners, fax machines, and multi-function devices. We also collected data for the ENERGY STAR Commercial Buildings branch on the types and amounts of miscellaneous plug-load equipment, a significant and growing end use that is not usually accounted for by building energy managers. For most types of miscellaneous equipment, we also estimated typical unit energy consumption in order to estimate total energy consumption of the miscellaneous devices within our sample. This data set is the first of its kind that we know of, and is an important first step in characterizing miscellaneous plug loads in commercial buildings. The main purpose of this study is to supplement and update previous data we collected on the extent to which electronic office equipment is turned off or automatically enters a low power state when not in active use. In addition, it provides data on numbers and types of office equipment, and helps identify trends in office equipment usage patterns. These data improve our estimates of typical unit energy consumption and savings for each equipment type, and enables the ENERGY STAR Office Equipment program to focus future effort on products with the highest energy savings potential. This study expands our previous sample of office buildings in California and Washington DC to include education and health care facilities, and buildings in other states. We report data from sixteen commercial buildings in California, Georgia, and Pennsylvania: four education buildings, two medical buildings, two large offices (> 500 employees each), three medium offices (50-500 employees each), and five small business offices (< 50 employees each). Two buildings are in the San Francisco Bay are a of California, nine (including the five small businesses) are in Pittsburgh, Pennsylvania, and five are in Atlanta, Georgia.

Worldwide status of energy standards for buildings

We present an international profile of activities and research issues related to energy standards for buildings. In the past decade, a few cross-national comparative studies have been published that address energy standards for residential buildings in industrialized countries. More detailed descriptions of a broader range of energy standard activities would be useful to countries seeking to improve or develop standards, particularly for non-residential buildings and in less-developed countries (LDCs). Toward this end, we developed a 15-page informal survey to gather specific information about the contents, development, and use of energy standards, particularly for non-residential buildings. This paper provides a snapshot of the legal status and coverage of energy standards in 57 countries. We have used survey results to characterize specific energy standards in 35 countries in greater detail, as well as to outline building energy-efficiency activities in seven countries without energy standards. Our project submits a possible framework for further inquiry into building energy standards research.

Estimation of Avoided Costs for Electric Utility Demand-Side Planning

Avoided costs originated with federal laws designed to encourage renewable energy and small power production. When estimated properly, they provide an unbundled characterization of the short- and long-run cost structure of a utility. We review current practices for estimating avoided costs for use in electric utility demand-side management (DSM) resource planning. For large DSM resource options, using avoided costs to estimate value is more accurate than using short-run marginal costs; avoided costs are simpler to use than traditional supply planning methods. We describe various administrative approaches for estimating avoided power generation costs and discuss modeling issues that arise in the estimation process. We also discuss emerging, market-based approaches for estimating avoided costs and describe current estimation practices for the additional, often substantial, non-generation-related costs avoided by DSM programs. Finally, we discuss special considerations in using avoided costs to estimate the ...

Energy-efficient lighting in Thai commercial buildings

We explore the opportunities to reduce the electricity required for lighting in prototypical Thai offices, hotels, and shopping centers. Using a whole-building energy analysis approach, we calculate the savings from lighting conservation measures directly, and from associated reductions in cooling load. Ancillary cost savings of air-conditioning energy and capacity comprise a significant 30 to 50% of the total. Lighting technologies considered in this study include electronic ballasts; tri-phosphor, narrow-diameter lamps; specular reflectors; occupancy sensors; lumen maintenance and daylighting controls; and compact fluorescent lamps. From a societal economic perspective, the cost of conserved energy of employing all applicable lighting conservation measures to these buildings is one-quarter or less than the average retail price of electricity for commercial customers, with a payback time of less than one year in hotels and retail buildings and approximately three years in offices. The internal rate of return for installing all lighting measures is 35% in offices, 142% for hotels, and 107% for shopping centers. Several current policy initiatives in Thailand, including a proposed energy standard for commercial buildings, with specific provisions for lighting, and plans by the nations electric utility to develop two commercial sector conservation programs, should help to spur the adoption of more efficient lighting products. We strongly recommend that the currently high tariffs and taxes (50% and greater) for imported efficient lighting products be reduced.

Testing the accuracy of a measurement-based building energy model with synthetic data

Abstract A new class of building energy models has emerged which use short-term measured data to predict energy performance for a longer period or for average conditions (such as “weather normalization”). Few of these models have been fully validated because tests are complex, and it is difficult to control all variables. One method of testing a measurement-based model is to use “synthetic” consumption data generated by a conventional building loads simulation model. A procedure to test the accuracy of one aspect of a measurement-based model is described and applied to a recently developed model. The model was found to yield significant errors in predicted annual space heating use, but revised algorithms greatly improved the models accuracy. The discovery, and subsequent correction of the errors, would have been much more difficult with field data.

Environmental externality surcharges in power system planning: a case study of New England

In several states, public utility commissions have adopted surcharges for environmental externalities (adders) to be used in electric utility planning. The Massachusetts adder system applies major surcharges to emissions of sulfur dioxide, nitrogen oxides, and carbon dioxide. The authors explore the implications in terms of cost and emissions of using the Massachusetts adders as shadow prices in dispatching the pooled electric power system in New England. The analysis has use of a probabilistic production cost simulation model to estimate the effects on the present system, and on a resource mix envisioned 15 years hence. The externality cost adders are used to influence the dispatch of a fixed configuration of power plants and are not used to affect the composition of the future resource mix. Compared to conventional dispatch, emissions of SO/sub 2/ and NO/sub x/ drop by 10% to 15%, while carbon emissions remain virtually unaffected. The production cost penalty is 3% to 4%. In each year, reductions are accomplished mainly by shifting generation away from New Englands coal steam power plants. >

Field power measurements of imaging equipment

According to the U.S. Department of Energy, electricity use by non-PC commercial office equipment is growing at an annual rate of nearly 5 percent (AEO 2003). To help address this growth in consumption, U.S. EPA periodically updates its ENERGY STAR specifications as products and markets change. This report presents background research conducted to help EPA update the ENERGY STAR specification for imaging equipment, which covers printers, fax machines, copiers, scanners, and multifunction devices (MFDs). We first estimated the market impact of the current ENERGY STAR imaging specification, finding over 90 percent of the current market complies with the specification. We then analyzed a sample of typical new imaging products, including 11 faxes, 57 printers and 19 copiers/MFD. For these devices we metered power levels in the most common modes: active/ready/sleep/off, and recorded features that would most likely affect energy consumption. Our metering indicates that for many products and speed bins, current models consume substantially less power than the current specification. We also found that for all product categories, power consumption varied most considerably across technology (i.e. inkjet vs. laser). Although inkjet printers consumed less energy than laser printers in active, ready and sleep-mode, they consumed more power on average while off, mostly due to the use of external power supplies. Based on these findings, we developed strategies for the ENERGY STAR program to achieve additional energy reductions. Finally, we present an assessment of manufacturers ENERGY STAR labeling practices.

Energy Efficiency Building Code for Commercial Buildings in Sri Lanka

1.1.1 To encourage energy efficient design or retrofit of commercial buildings so that they may be constructed, operated, and maintained in a manner that reduces the use of energy without constraining the building function, the comfort, health, or the productivity of the occupants and with appropriate regard for economic considerations. 1.1.2 To provide criterion and minimum standards for energy efficiency in the design or retrofit of commercial buildings and provide methods for determining compliance with them. 1.1.3 To encourage energy efficient designs that exceed these criterion and minimum standards.

DSM bidding-- the next generation

Abstract Early experience with DSM bidding suggests nonutility service providers can absorb substantial risk of performance, although bid prices are sometimes high. ESCOs and utilities are moving toward partnerships that make good use of the strengths of both groups.