the liquid fuel is pumped into a vehicle fuel tank or the vessel may be the vehicle fuel tank application_number US 82983010 A description it has been found that a fuel composed of an approximately 50 50 mass mixture of liquid petroleum gas lpg and compressed natural gas cng offers a variety of advantages over other types of alternative fuels such as vehicle mileage range while maintaining both economical and environmental superiority the composite fuel has been shown to reduce some of the problems associated with the use of commercial compressed natural gas cng or commercial liquid petroleum gas lpg for example the fuel is stored at approximately half the pressure of cng approximately 1500 psig but retains the high energy density of lpg an example of a fuel composed of a 50 50 mass mixture of liquid petroleum gas lpg and compressed natural gas cng is disclosed in u s pat nos 5 900 515 and 6 111 154 issued to mallinson et al each of which is hereby incorporated herein by reference preferably the two phase fuel mixture comprises a gaseous methane and at least one other hydrocarbon and a mole percent of methane from about 50 percent to about 80 percent the mixture of methane and the at least one other hydrocarbon maintained at a temperature of about u2212 1 u00b0 c.