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. Common examples of solid fuels include wood (see wood fuel), charcoal, peat, coal, Hexamine fuel tablets, and pellets, which can be made from wood (see wood pellets), corn, wheat, rye and other grains. Solid fuels are also extensively used in rocketry as a propellant (see solid propellants).

Solid fuels have been used by humanity for many years to create fire. Wood was used extensively to run steam locomotives. Both peat and coal are still used in electricity generation today.

The use of some solid fuels (e.g. coal) is restricted or prohibited in some urban areas, due to unsafe levels of toxic emissions. The use of other solid fuels such as wood is increasing as heating technology and the availability of good quality fuel improves. In some areas, smokeless coal is often the only solid fuel used. In Ireland, peat briquettes are used for home heating. They are also used to start a coal fire.

Solid fuels are contrasted with liquid fuels and gaseous fuels.

The amount of coal worldwide is approximately 1 trillion metric tons while more is left over in unknown areas. United States currently holds the majority of coal and bituminous reserves while Russia comes in second, and China follows in third place. The United States currently holds around 400 years of coal in now established reserves, which are currently in use. True totals of coal reserves could be higher if accessible mining methods were more fully used, and could even be higher if new methods are considered. Canada is also a contender in this list, but available reserves are left unexploited in the region east of the Alberta oil sands deposits. Coal, because of its comparatively low cost, is the most likely to fuel the world’s energy needs. However, carbon provides most of the thermal energy from coal. The high carbon content presents environmental problems. There has been a lack of natural gas lately; this could require that the United States look for alternative sources of fuel.

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