PURPOSE: To obtain a mechanism for heat transfer excellent in efficiency and stability and having an arbitrary shape over a wide range by an arrangement wherein a member partially comprises a flake of thermally conductive material, a wire or coarse metal powder sintered onto the member or the member itself is made fully or partially of a sintered material.

CONSTITUTION: A member is fully made of metal flakes compacted using a die before being sintered thus forming a member having high transparency. The cylinder-like member 1 is exposed to intensive solar beam in a solar energy unit and when the air flows from the front 2 to the other front 3 of the member 1, it is heated up to 800°C or above before being used for energy acquisition. Of course, a lateral air flow is also possible. Alternatively, other medium may be used for transferring heat from the member 1.