A dual rail heat pump cycle includes a low-temperature heat source; a two stage, high-temperature heat exchange process through which, in operation, heat is exchanged with a thermal medium; and a working fluid circuit. The working fluid circuit includes an expansion process; a compression process; a recuperation process, and a pair of parallel flow paths. The recuperation process is interposed between the expansion process and the compression process and has a high-pressure side defined by the compression process and a low pressure side defined by the expansion process. The pair of parallel flow paths between the recuperation process and the high-temperature heat exchange process on the high-pressure side of the recuperation process.