Industrial heat and the last 20 percent
A review commissioned by a European energy agency argues that electrification of low-temperature industrial heat (below 200 °C) is now cost-competitive in most member states, but that the remaining “last 20 percent” of process heat — cement kilns, primary steel, high-temperature chemicals — will not follow the same path. Those processes need either green hydrogen, biomass, or carbon capture, each of which faces a different bottleneck: hydrogen is limited by electrolyser build-out and electricity price; biomass is limited by sustainable supply; capture is limited by storage geology and public acceptance.
The authors warn against treating the last 20 percent as a single policy problem. A subsidy designed for hydrogen-ready steel will do little for a lime kiln whose owners cannot site a storage well. They propose that public support be tagged to a measured tonne of abated process heat, not to a favoured technology, and that permitting timelines be published as a leading indicator. Critics reply that technology-neutral auctions systematically under-reward first-of-a-kind plants, whose capital costs sit well above the auction clearing price.
The review does not claim that the last 20 percent is unsolvable. It claims that pretending it is the same problem as heat pumps for warehouses will waste a decade.