A solar energy collection system comprises hollow radiation absorber(s) in an enclosure, each absorber for filling with working fluid, to absorb radiation impinging thereon and transform its energy into heat to thereby heat the fluid. The system comprises an inlet non-return valve upstream of each absorber, for allowing a flow of the fluid thereto; and an outlet valve downstream of each absorber for allowing a flow of the fluid out. The system comprises a measuring device for determining parameter(s) of the fluid within each absorber, which depends on the heat absorbed thereby; and a controller that controls operation of at least the outflow valve between its open state in which the fluid can flow freely out of the associated absorber, and its closed state in which the fluid filling the associated absorber is held therein for a period of time depending on a desired change of the parameter.