Answer: synfuel

AnswerCrossword Clue
SYNFUELBiomass product
SYNFUELShale oil, for instance
SYNFUELGas from shale
synfuela liquid or gaseous fuel derived especially from a fossil fuel that is a solid (as coal) or part of a solid (as tar sand or oil shale)
synfuela fuel derived from fossil fuels
synfuelsynthetic fuel