NOVELTY - Converting hydrocarbon material to liquid fuel, involves: utilizing a renewable energy source to generate oxygen; supplying a combination of oxygen and steam to a synthesis gas generation unit, where relative amounts of oxygen and steam vary in accordance with an amount of renewable energy source used; feeding hydrocarbon feedstock to the synthesis gas generation unit; producing synthesis gas in the synthesis gas generation unit using a combination of steam reformation and partial oxidation of the hydrocarbon feedstock; and converting the synthesis gas into a liquid fuel.    USE - For converting hydrocarbon material to liquid fuel (claimed). The hydrocarbon feedstocks include municipal and industrial waste, biomass, coal and natural gas. The liquid fuels produced include methanol, ethanol, synthetic diesel (Fischer-Tropsch), and aviation fuel.    ADVANTAGE - The method maintains liquid fuel production at a desired level by use of supplemental electricity from nonrenewable sources and from storage of the oxygen. It provides the flexibility to operate at substantially reduced liquid fuel production levels. The cost of electricity used in the hydrocarbon to liquid fuel conversion facility is reduced by colocating the facility at a wind or solar energy farm. In addition, the electricity cost is minimized by using surplus wind or solar electricity that cannot be accommodated by a downstream load or by the electrical transmission system. In addition, landfill gas can be used to provide power for the hydrocarbon to liquid fuel production process. The method and systems provide improved use of electricity from renewable energy sources, such as wind or solar energy, through the conversion of hydrocarbon feedstocks into a liquid fuel. These systems can both reduce the cost of producing liquid fuels from hydrocarbon feedstocks and also decrease carbon dioxide (CO2) emissions. The economics for these methods of employing renewable electricity to produce liquid fuels are attractive because the electricity cost is low. The cost of electricity could in fact be negative when the renewable energy source produces energy that exceeds what the electricity dispatcher asks for. Moreover, there is minimal electricity transmission system cost for the synthesis or hydrogen gas generation unit. The most economically attractive approach is use of surplus renewable electricity that cannot be sent to the grid for downstream use, it is, also possible to use a greater fraction or all of the renewable generated electricity. The system could be used to increase the use of stranded natural gas which cannot be transported to the end user by pipe line. Using renewable energy, such as windpower, the greenhouse gas emissions from converting natural gas into a liquid fuel are significantly reduced.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a system for converting hydrocarbon material to liquid fuel, comprising: a synthesis gas generation unit configured to receive a combination of oxygen and steam, where relative amounts of the oxygen and steam vary in accordance with an amount of renewable energy source used, and the synthesis gas generation unit is configured to produce synthesis gas using a combination of steam reformation and partial oxidation of the hydrocarbon feedstock; and a liquid fuel production plant configured to convert the synthesis gas into liquid fuel.