Coal is a fundamental fossil fuel, crucial to industrial history. Chemically, it's a sedimentary rock composed primarily of carbon, but containing various hydrocarbons and impurities.

In the steel industry, coal is vital as a reducing agent in the traditional Blast Furnace (BF) process.

It's converted into coke, where its carbon removes oxygen from iron ore, a reaction that releases significant CO₂.

While cheap and abundant, its high carbon intensity makes it the single most significant target for decarbonization efforts, such as the transition to hydrogen.