Control and Measured Performance of a Passive Off-Peak Storage System

The energy consumptions in two similar townhouses were monitored over the 1985-86 heating season to gain field experience with the concept of passive off-peak storage. In one of these all-electric passive solar residences, a constant off-peak charge of a brick wall by embedded electrical wires provided a base load while the comfort requirements were met by conventional convectors. The second building was used as a reference building and had an identical mass wall but without the embedded electrical wires. Two separate analyses, with similar very cold weather showed: (1) a 10 to 40% reduction in baseboard energy consumption during the on-peak period; (2) a 30 to 80% reduction in baseboard energy consumption during the high demand hours of the day. From December to February the storage accounted for 46 to 79% of the average daily heating load of the test units.