| abstract |
A thermal energy storage apparatus and method employs a container formed of soda lime glass and having a smooth, defect-free inner wall. The container is filled substantially with a material that can be supercooled to a temperature greater than 5 DEG F., such as ethylene carbonate, benzophenone, phenyl sulfoxide, Di-2-pyridyl ketone, phenyl ether, diphenylmethane, ethylene trithiocarbonate, diphenyl carbonate, diphenylamine, 2-benzoylpyridine, 3-benzoylpyridine, 4-benzoylpyridine, 4-methylbenzophenone, 4-bromobenzophenone, phenyl salicylate, diphenylcyclopropenone, benzyl sulfoxide, 4-methoxy-4PR-methylbenzophenone, N-benzoylpiperidine, 3,3PR,4,4PR,5 pentamethoxybenzophenone, 4,4'-Bis-(dimethylamino)-benzophenone, diphenylboron bromide, benzalphthalide, benzophenone oxime, azobenzene. A nucleating means such as a seed crystal, a cold finger or pointed member is movable into the supercoolable material. A heating element heats the supercoolable material above the melting temperature to store heat. The material is then allowed to cool to a supercooled temperature below the melting temperature, but above the natural, spontaneous nucleating temperature. The liquid in each container is selectively initiated into nucleation to release the heat of fusion. The heat may be transferred directly or through a heat exchange unit within the material. |