English

Two residential sized air conditioners were tested in psychrometric rooms at reduced evaporator airflows ranging from 0 to 50% below that recommended by the manufacture of each of the units. Outdoor temperatures ranged from 35 to 49 °C. One of the units used a thermal expansion valve for flow control while the other unit used in short tube orifice. Performance of the units was quantified by the capacity, power, coefficient of performance, and sensible heat ratio.

Research over the past five years has indicated that a significant majority of the cost of residential retrofit duct sealing is in the labor required to find and seal those leaks. This paper describes the results of a field investigation of the performance and practicality of sealing residential duct leaks from the inside by means of a technique based upon injecting a fine aerosol spray into the duct system. The field results presented are from 4 7 houses located in Florida.

In an effort to optimize the energy performance of existing single-family housing, the Advanced Retrofit pilot program was sponsored by Massachusetts Electric and administered by Conservation Services Group. The intent of the program was to advance the direction of energy conservation by achieving the highest energy savings possible, by combining field experience with innovative technologies in electrically heated homes. Cost-effectiveness was not a constraint in this pilot program.

We present a simple model to calculate the energy loss by free cooling at night. The time dependence of the exhaust air and wall surface temperatures is predicted by a simplified dynamic model that couples air flow, heat transfer, and wall temperature. For given ventilation rate the model predicts that the total heat extracted from the building during the night can be maximized by increasing the heat exchanging surface area and the thermal effusivity, of the wall materials. The influence of ventilation rate on the heat removed by freecooling at night is discussed.

Night cooling is a viable technique in the UK, but there is no suitable commercially available equipment. The BRE has been testing prototype ventilators and concludes that they work although weather, security and acoustics issues need to be addressed.        

How do tenants of public housing respond to retrofits to improve their comfort and energy use during the cooling season? In contrast to retrofits to improve heating or lighting, cooling retrofits have been little studied, despite extensive programs by utilities and housing authorities to reduce this end use. A local utility and a housing authority have been retrofitting their buildings with evaporative coolers, ground-source heatpumps and other cooling measures.

There are many hurdles in the road to widespread adoption of energy-efficient heating and cooling (HVAC) equipment in homes. These hurdles include increased first cost, lack of sufficient financing, historic lack of aggressive marketing by HVAC equipment dealers, and lack of consumer awareness. This paper reports on the design and progress of the ENERGY STAR market-based approach to overcome these hurdles to encourage the widespread manufacture and purchase of highly efficient heating and cooling equipment.

Manufactured homes, often referred to as HUD-code homes, are continuing to grow in importance as a national housing resource and represented 23% of all new home construction in 1995. In spite of groundbreaking work to characterize the performance of air distribution systems in site-built housing, in new manufactured homes, the subject has been largely ignored. Field data was gathered from 24 typical new HUD-code homes in four regions in the continental United States. This study describes air distribution system losses estimated through an analysis of system and distribution efficiencies.

This paper examines key issues involved in evaluating benefits of tree planting programs from the perspective of electric utilities, as well as from a wider perspective of public and private entities that may benefit from such programs. The nation's largest shade tree program, sponsored by the Sacramento Municipal Utility District (SMUD) in collaboration with the Sacramento Tree Foundation (STF), is used as a case study.