System for recovering solar energy and its direct utilization

Claim 1

A heating system utilizing alternatively solar and fuel energy comprising a first heating fluid circuit exploiting solar energy and a second heating fluid circuit exploiting fuel energy, said first circuit including collector or absorber means for radiant solar energy adapted to heat said heating fluid of said first circuit and having an inlet for the heating fluid to be heated in said collector or absorber means and an outlet for the heating fluid heated therein to be circulated in said first heating fluid circuit, heat exchanger utilization means, said utilization means having an input for the heating fluid and an output therefor, first pipe means directly connecting said outlet of the collector or absorber means with said input of said heat exchanger utilization means, first valve means in said first pipe means for selectively allowing and preventing fluid flow therethrough, a heat storage means, second pipe means connecting the output of said heat exchanger utilisation means with said heat storage means, third pipe means connecting said heat storage means with said inlet of said collector or absorber means, first by-pass pipe means having one end thereof hydraulically connected with said second pipe means at a point situated between said heat exchanger means and said heat storage means, said first by-pass pipe means having another end thereof hydraulically connected with said third pipe means at a point situated between said heat storage means and said inlet of said collector or absorber means, second valve means at said one end of said first by-pass pipe means for selectively allowing and preventing fluid passage through said first by-pass pipe means towards said collector or absorber means and through said second pipe means towards said heat storage means, and second by-pass pipe means having one extremity thereof connected with said heat storage means and having another extremity thereof connected with said first pipe means in a point situated between said first valve means and the input of said heat exchanger means, first pump means in said first pipe means for creating a stream of said heating fluid directed from said collector or absorber means towards said heat exchanger means and therefrom towards said heat storage means and therefrom towards said inlet of said collector or absorber means and alternatively from said heat exchanger means towards said first by-pass pipe means and therefrom towards said inlet of said collector or absorber means via said third pipe means, and first temperature responsive control means for controlling said pump means and the setting of said first and second valve means, said second heating fluid circuit exploiting fuel energy being hydraulically separated from said first heating fluid circuit and having a fuel heated boiler, and own heat exchanger utilisation means, and pump and valve means for circulating the heating fluid, and second temperature responsive control means controlling the operation of the own valve and pump means of said second heating fluid circuit, said second temperature responsive control means having at least one temperature sensitive element responsive to the temperature of the heating fluid of said first heating fluid circuit in at least one point thereof, to put in operation said second heating fluid circuit when the heating fluid of said first heating fluid circuit is below a prestablished value.