Using a Whole-House Fan to Decrease Air-Conditioning Energy Use - Estimate of Energy Savings and Economic Viability for Residential Applications

摘要

During periods of the day (primarily during the evening or early morning hours), a whole-house fan can be used in place of a central air-conditioning system to provide space cooling for residential structures. The fan generally requires only one-half or less the power required to operate the air-conditioning system. Thus, energy savings result. This analysis examined the energy savings potential and economic feasibility of the whole-house fan when used in conjunction with a typical air-conditioning system. A prototypical house design was used, and an hour-by-hour simulation was performed for 22 cities representing various climates. It was assumed that the fan would be operated when the ambient temperature was between 21 and 27 exp 0 C (70 and 80 exp 0 F) and that it would be turned off between midnight and 6 a.m. The results of the analysis show that the whole-house fan is economically attractive (i.e., a simple payback of <5 years) in only two cities (both of which are desert-type climates) and then only when owner installed. Because of the limited applicability of the concept, it is recommended that the whole-house fan can not be included in the Residential Conservation Service model audit if it is to be used in conjunction with a central air-conditioning system. However, the whole-house fan may be a competitor to central air-conditioning in Northern climates. An analysis of this option is recommended. (ERA citation 08:051491)