Green steel and intermittency risk

Originally posted here.

• Decarbonising the steel industry is a monumentally complex undertaking

• Electrification will be key to making ‘green’ steel

• Electrification-based pathways hold great promise, but there is no silver bullet

• The intermittency of renewables is both a help and a hindrance

Decarbonising steel will be one of the toughest challenges in the transition to a low-carbon economy. It is vital to achieving a ‘deep’ transition since the steel industry is a major emitter, and because the transition itself will require vast amounts of steel. Wind turbines, solar panels and transmission towers all need steel.

There are many ways to produce ‘green’ steel, and none of them are perfect. Each has its pros and cons, and all will play a role. Carbon capture, hydrogen and electrification will be needed, as well as other technologies and process improvements.

I won’t explain here the many pathways for making green steel because it would require a separate post and others have done a comprehensive job (this report gives a good overview). Instead, I want to focus on two pathways in particular, and the very different ways that renewable energy intermittency affects the technical and economic viability of each one.

Electrification is a major component of steel decarbonisation. Conventional production techniques involve mining and shovelling coking coal into blast furnaces to reduce iron ore into iron – the first and most emissions-intensive step in the steelmaking process. Electrification skips the ironmaking step by recycling scrap back into usable steel, meaning it can significantly reduce the amount of coking coal used in steelmaking rapidly and at scale.

Read the full article here.