Abstract: The present invention comprises (1) a heat source, (2) a heat pipe, and (3) a thermal transformer in thermal contact with said heat pipe and proximately disposed to said heat source, whereby a uniform heat transfer from said heat source to a heating system is obtained. The thermal transformer includes (1) a container, (2) a working fluid and its vapor which are essentially in equillibrium, (3) evaporating surfaces depending from the internal surfaces of the transformer that are wetted with the working fluid and that are proximate to the heat source, and (4) condensing surfaces depending from the exterior of those areas of said heat pipe that are in thermal contact with said transformer.