The present invention relates to a fuel for a fuel cell system comprising 5 vol.
% or more of hydrocarbons based on the whole fuel, and 0.5-20 mass % of oxygenates
in terms of an oxygen content based on the whole fuel, wherein the content of hydrocarbon
compounds having a carbon number of 4 is 15 vol. % or less, the content of hydrocarbon
compounds having a carbon number of 5 is 5 vol. % or more, the content of hydrocarbon
compounds having a carbon number of 6 is 10 vol. % or more, the content of hydrocarbon
compounds having carbon numbers of 7 and 8 in total is 20 vol. % or more, and the
content of hydrocarbon compounds having carbon numbers of 10 or more is 20 vol.
% or less.
