Chemical energy storage system

Apparatus for transferring heat comprising

• a first vessel containing a liquid solution of a compound selected from the group consisting of alkali and alkaline earth metal hydroxide, halide and thiocyanate, ammonium halide and thiocyante, and mixtures thereof, said solution having an initial concentration of between about 30% and about 80%, by weight of said compound, said liquid selected from the group consisting of water, ammonia an alcohol having between 1 and 8 carbon atoms, glycerol, glycols, polyglycols, glycol ethers, aliphatic amines and alkanol amines having between 1 and about 6 carbon atoms, and mixtures thereof, and a first space above the level of said liquid solution and means for pumping said liquid solution to distribution means for directing said liquid solution into said first space,
• a second vessel containing said liquid without said compound therein, and a second space above the level of said liquid and means for pumping said liquid to distribution means for directing said liquid into said second space,
• both said first and second vessels being closed to atmosphere and capable of holding a vacuum,
• conduit means communicating between said first space and said second space for allowing liquid vapor and pressure changes to pass therebetween, and valve means cooperating with said conduit means for terminating communication between said spaces,
• heating means for heating said solution to a temperature of above about 90.degree. F., and cooling means for cooling said liquid to a temperature below about 55.degree. F.,
• first heat exchange means cooperating with said first vessel for transferring heat from heated solution therein, and
• second heat exchange means cooperating with said second vessel for transferring heat to liquid therein.