Abstract: There is provided a solar collector apparatus comprising a rotatable platen supporting a solar collector, means for rotating the platen such that the solar collector follows the wandering of the sun, said solar collector comprising a plurality of elongated parallel sun radiation concentrators, each concentrator being associated with an elongated conduit which is arranged to be subjected to the radiation concentrated by the concentrator, and pump and control means for circulating a liquid through the conduits via a liquid magazine, the concentrators being located on the platen with their longitudinal axes aligned in the vertical plane of the solar direction, said means for rotating the platen being adapted to maintain such alignment of the concentrators.