Coal is mainly utilized as fuel for electricity production and industries such as steel, cement, lime, and others. It will be less investment than the direct electricity usage. In general, it will be fuel for activities such as water boiling to send the steam to spin the turbine of electricity production or sent the steam to bake such as rubber baking or wood baking, etc.
Other than the direct combustion, the coal can be converted to be other fuel forms through the coal liquefaction or coal gasification. Coal is utilized as clean fuel in order to reduce the pollution from utilizing the coal as fuel. Under the coal conversion process, acidic or toxic gas can be separated. By-product substances obtained from coal can be utilized in other ways such as sulfur used for sulfuric acid and gypsum production, ammonia used as fertilizer for agriculture, coal ash used for building material production, etc.