Thermal Energy Storage in Forced-Air Electric Furnaces

Experimental data are presented for heat storage in forced-air electric furnaces using magnesite as the heat storage material. Charge and discharge data for temperature and flow, obtained in the laboratory, are compared with models used for the design of the furnace. Experience with the furnace operating in homes for a heating season and being charged during the off peak is also presented. A description of the furnace and the control system used to control air flow and temperature is given along with a brief summary of cost and market potential. The capability of sodium sulfate bricks as a replacement for the more expensive magnesite bricks is summarized. The results of cycling tests that show its improved mechanical strength with the addition of binder materials are discussed.