Since the 1973 oil embargo, substantial interest has focused upon the question of the cost competitiveness of solar space heating and domestic hot water systems for single family residences. As early as 1974, national surveys indicated that homeowners were seriously considering the use of solar systems (National Science Foundation). At the present time, several New England electric companies (Massachusetts Electric, Granite State and Narragansett) are testing commercially available solar domestic hot water heaters in 100 New England homes. Yet, the question of the cost competitiveness of solar systems remains unresolved. For example, a recent study by the Massachusetts Energy Policy Office suggests that solar systems are currently cost competitive with electric resistance heating in the Boston area. The interim findings reported by consultants to the New England Electric Companies conclude that “Solar energy is a victim of unreasonably high expectations … and that several problems must be resolved if solar domestic hot water heaters are to become economically viable.” (Little, p. 3). A number of other studies have also arrived at conflicting results (Bezdek, et al; G. Lof and R. Tybout; W.D. Schulze, et al).