Installation and assessment of crushed rock heat storage furnaces

Public Service Electric & Gas Company (PSE&G) participated in installing and evaluating a prototype crushed-rock heat storage furnace. The authors describe PSE&G´s experience during the installation and the assessment of the furnace´s operation. Two furnaces were installed during October 1985 in two test homes. An initial result of the tests was that the crushed rock furnace could be a viable option for home heating under certain conditions. Overall seasonal energy usages (kWh) for heating were about 30% less than the standard gas furnace in both test homes. On average, on-peak electrical energy usages of these pilot units (the energy used by house fan) was less than 2% of the total furnace usages. Approximately 98% of the total furnace electrical energy of these units was utilized during off-peak hours