Cryogenic Heat Engines for Powering Zero Emission Vehicles

Progress on advancing the technology of using cold thermal reservoirs for mobile energy storage applications is reported. A heat engine such as a Stirling engine can operate using the cold thermal reservoir as a heat sink and the atmosphere as a heat source. A heat engine as developed by the authors that operates employing a sub-atmospheric temperature thermal reservoir such as liquid nitrogen as a heat sink has been called a “cryogenic heat engine.” With sufficient work produced per unit mass of liquid nitrogen, such a cryogenic heat engine may be suitable for powering short range, non-polluting automobiles.