Climate activists are fond of saying that we have all the solutions we need to the climate crisis; all we lack is the political will.

While it’s true enough as policy goes — we certainly have enough solutions to get started and make big changes — as a technical matter, it is incorrect. Truly defeating climate change will mean getting to net-zero carbon emissions and eventually negative emissions. That means decarbonizing everything. Every economic sector. Every use of fossil fuels.

And actually, there are some sectors, some uses of fossil fuels, that we do not yet know how to decarbonize.

Take, for instance, industrial heat: the extremely high-temperature heat used to make steel and cement. It’s not sexy, but it matters.

Heavy industry is responsible for around 22 percent of global CO2 emissions. Forty-two percent of that — about 10 percent of global emissions — comes from combustion to produce large amounts of high-temperature heat for industrial products like cement, steel, and petrochemicals.

To put that in perspective, industrial heat’s 10 percent is greater than the CO2 emissions of all the world’s cars (6 percent) and planes (2 percent) combined. Yet, consider how much you hear about electric vehicles. Consider how much you hear about flying shame. Now consider how much you hear about … industrial heat.

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