Solid fuel

Solid fuel refers to various forms of solid material that can be burnt to release energy, providing heat and light through the process of combustion. Solid fuels can be contrasted with liquid fuels and gaseous fuels. Common examples of solid fuels include wood, charcoal, peat, coal, hexamine fuel tablets, dry dung, wood pellets, corn, wheat, rice, rye, and other grains. Solid fuels are extensively used in rocketry as solid propellants.^[1] Solid fuels have been used throughout human history to create fire^[2] and solid fuel is still in widespread use throughout the world in the present day.^[3][4]

Solid fuel from biomass is regarded as a renewable energy source which can contribute to climate change mitigation efforts. Solid fuel from fossil fuels (i.e. coal) is not a renewable energy.