A heat collector (10, 20) includes a heat absorption surface (12, 22), an opposite heat focus surface (11, 21) and one or more surrounding sides (13, 23). A matrix (24) of the heat collector is a thermally conductive material. There is an adiabatic dope (25) mixed within the matrix. A relative concentration distribution of the adiabatic dope increases from the heat absorption surface to the heat focus surface, and decreases from the surrounding sides to a center of the heat collector. The shape of the heat collector can be rectangular, cylindrical, prismatic, plate-shaped, square, or polyhedral. The heat collector can draw heat generated from electrical components, and collect the generated heat for reuse in order to enhance energy efficiency.