Abstract: A collector element for collecting solar energy. The collector element is made of metal and comprises at least one elongated central ridge comprising at least one internal flow channel for a heat transfer medium, first and second elongated side ridges at opposite sides of the at least one central ridge and an elongated depression between each two adjacent ridges. At least one side ridge comprises at least one fastening element by means of which at least one substantially solar radiation permeable covering element is to be fastened to the collector element for covering at least the at least one elongated central ridge of the collector element.

Abstract: A solar collector arrangement comprises at least two solar collectors, each solar collector comprising at least one collector element with at least one flow channel for receiving heat transfer medium to be heated in the solar collector. The at least two solar collectors are arranged in parallel connection relative to each other and the heat transfer medium to be heated in the solar collectors and the heat transfer medium heated in the solar collectors are arranged to flow into the solar collectors and out of the solar collectors in turns one or some solar collectors of the solar collector arrangement at a time.

Abstract: A collector element for collecting solar energy. The collector element is made of metal and comprises at least one elongated central ridge comprising at least one internal flow channel for a heat transfer medium, first and second elongated side ridges at opposite sides of the at least one central ridge and an elongated depression between each two adjacent ridges. At least one side ridge comprises at least one fastening element by means of which at least one substantially solar radiation permeable covering element is to be fastened to the collector element for covering at least the at least one elongated central ridge of the collector element.

Abstract: The invention relates to a solar collector (1) comprising a collector element plane comprising a set of parallel metallic collector elements (2) for collecting solar energy. The collector element plane, on its side to be arranged to face the sun, comprises a set of parallel, elongated ridges (R, r) formed by the metallic collector elements (2), and elongated depressions (v) between the ridges (R, r), and that at least some of the ridges (R, r) comprise therein a channel (3) for a heat transfer medium. The invention also relates to a collector element. The invention further relates to a building roof, a building, and a solar energy recovery system comprising said solar collector (1).

Abstract: The invention relates to a solar collector (1) comprising a collector element plane comprising a set of parallel metallic collector elements (2) for collecting solar energy. The collector element plane, on its side to be arranged to face the sun, comprises a set of parallel, elongated ridges (R, r) formed by the metallic collector elements (2), and elongated depressions (v) between the ridges (R, r), and that at least some of the ridges (R, r) comprise therein a channel (3) for a heat transfer medium. The invention also relates to a collector element. The invention further relates to a building roof, a building, and a solar energy recovery system comprising said solar collector (1).