[jl6]

Steel is cheap for two reasons: unaccounted externalities of the use of coal in the process, and massive scale. Coal-free steel is possible, but we don’t currently do it at scale, so there is work to do.

Recycling will make sense if steel becomes much more expensive, but a future with really expensive steel is not what we should be aiming for.

[pfdietz]

The issue holding back steel recycling is contamination, most notably with copper. This forces recycled steel to be "downcycled" into lower value uses like rebar, or the recycled metal to be diluted with freshly reduced metal. A means to remove copper from molten steel is needed; there are some ideas for this being pursued.

https://www.sciencedirect.com/science/article/abs/pii/S09213...

[tialaramex]

The externalities for burning coal to make steel aren't acceptable though, we would need the mythical high performance carbon capture solutions and those aren't materialising, everybody who promised more efficient solar did what they promised, bigger wind turbines, as promised, more compact storage, as promised - but the carbon capture is MIA.