A recuperative and conductive heat transfer system (10, 10′) that is operative to effect therewith the heating within the second portion (20, 20′) of the heat transfer system (10, 10′) of a “working fluid” flowing through the heat s transfer surfaces (32, 32′) as a consequence of the transfer thereto by conduction of heat from a multiplicity of regenerative solids (24, 24′). The multiplicity of regenerative solids (24, 24′) derive their heat from a recuperation thereby within the first portion (12, 12′) of the heat transfer system (10, 10′) from either an internally generated or an externally generated source of heat (22, 22′).