It's a massive first step to decarbonizing a carbon-heavy industry, as steel-making worldwide accounts for 8% of all CO2 emissions resulting from the need for coal in the manufacturing process, and the firms involved in the discovery represent 10% of Sweden's emissions, and 7% of Finland's.

Since the Warring States period in Ancient China, and in India and Sri Lanka four centuries before that, metalworkers have understood that to take a useful metal, iron, and turn it into a superior alloy, steel, they needed very high heat and a bit of coal.