 LN2 is exposed to ambient heat in the car and the resulting nitrogen gas can be used to power a piston or turbine engine.The maximum amount of energy that can be extracted from LN2 is 213 Watt-hours per kg (W·h/kg) or 173 W·h per liter, in which a maximum of 70 W·h/kg can be utilized with an isothermal expansion process.Such a vehicle with a 350-liter (93 gallon) tank can achieve ranges similar to a gasoline powered vehicle with a 50-liter (13 gallon) tank.