Abstract: A method and an apparatus for storing heat energy in a hybride heat storage apparatus comprising a first and a second material are disclosed, the first and the second materials having different melting temperatures and different densities and being non-mixable. When heat is discharged from the heat storage apparatus, the first material, which has the lower melting temperature, is brought into direct heat exchanging contact with the second material which is essentially in a liquid state by causing droplets of the first material having a lower temperature than the melting temperature of the second material to pass through the second material, whereby the droplets of the first material are heated and may be used in order to give off the heat in an outer circuit, while the second material sets essentially in droplet form.

Abstract: The invention pertains to an automatic heat storage system comprising two cooperating sources of heat, two heat storage vessels, and a heat emitting system, the heat being transferred by a heating medium common for the entire system. Preferably, one of the sources of heat is a solar energy collector system.