Net energy analyses of eight technologies to provide domestic hot water heat

Abstract

Net energy analyses have been carried out for eight trajectories which convert an energy source into heated domestic water. In addition, economic and metals consumed estimates have been made for three methods of producing heated domestic water. While some of the trajectories producing electrically heated water showed a slightly higher ratio of energy produced to energy consumed than a flat plate solar collector system, when all factors were considered (i.e. cost, quality of energy, and metals consumed), the flat plate solar collector system appears to be the system our energy policy should encourage for heating domestic water, even in the cloudy inter-Lakes area of the United States. Based on only net energy factors, it seems clear that the synthetic fuels program should not be encouraged as a means of providing a fuel source for heating domestic water.