Abstract: A method and apparatus for conserving waste energy by transferring waste heat from an internal combustion engine, solar energy or from any other source of waste heat energy of a temperature of 200.degree. F. or above to a carrier liquid includes conveying the heated carrier liquid to a heat exchanger, pressurizing a refrigerant by heating the refrigerant with heat energy extracted from the heated carrier liquid and performing work with the pressurized refrigerant. The preferred embodiments include a modified Rankine-Sterling cycle engine and a dual absorption generator system.