How fast can European steelmakers decarbonise?

At the steelworks near the German city of Salzgitter, ironmaking is a dramatic affair. Red-hot molten metal pours forth from the bottom of towering blast furnaces. The noise is deafening. Sparks fly everywhere. Soon things will be much more sedate. Seven wind turbines already tower over the site, run by a firm called Salzgitter AG. In a few years the electricity they generate will power banks of electrolysers, container-sized machines that split water into oxygen and hydrogen. The hydrogen will replace coke in reducing iron ore to iron in a new type of furnace, which will operate at much lower temperatures. Instead of CO₂, the process will emit H₂O.