But coal was merely at the pointy end of a decline across fossil fuels as a whole, with oil and natural gas also hit harder than renewables. Earlier in April, the IEA forecast that global oil demand was expected to fall by 9.3 million barrels per day during 2020—an unprecedented annual drop. On Thursday, the agency said natural gas, too, was facing a sharp drop, with a forecast decline of 5% year-on-year, after a decade of uninterrupted growth.

Fossil fuels are being squeezed from both directions, the agency notes. On the one hand, from the evaporation of demand as a whole, and on the other, from the rise of affordable renewable power—particularly solar, but extending to all low-carbon sources, including hydropower and nuclear.

That surge has been most apparent in electricity, where low-carbon sources are expected to collectively account for 40% of the world’s electricity generation, taking a six percentage point lead on coal as a source of power, the IEA said—although they are making up a greater share of a smaller pie, with electricity demand itself expected to drop by 5% this year, the largest decline since the Great Depression.

“This is a historic shock to the entire energy world,” says Fatih Birol, the IEA executive director. “Amid today’s unparalleled health and economic crises, the plunge in demand for nearly all major fuels is staggering, especially for coal, oil, and gas. Only renewables are holding up during the previously unheard-of slump in electricity use.”

As a result, he warns, the energy industry that emerges from the crisis “will be significantly different from the one that came before.”

The impact on global emissions is expected to be immense. Global energy-related CO2 emissions are projected to fall by 8% in 2020, the IEA says, essentially lowering emissions to levels last seen a decade ago. It is expected to be the largest-ever fall, a drop six times the size of the decline in 2009, during the financial crisis.

That change in global energy dynamics in many ways reflects the sudden jolt to the way we are using energy: at home, for heating and electricity—a sector that is already far closer to being decarbonized than the transport sector, which has in many ways nearly ground to a total halt.

With countries in lockdown, energy demand as a total is expected to plunge by 6% this year, seven times the drop during the last financial crisis. That drop is expected to be the sharpest in the U.S. (down 9%) and the EU (down 11%), and is expected to drop a further 1.5% for every additional month of a global lockdown, the IEA says.

But the reduction was “nothing to cheer,” warns Birol, echoing comments he has made in the past that any reductions are a result of “economic meltdown” rather than the more robust alternative: long-term policy decisions.

“If the aftermath of the 2008 financial crisis is anything to go by, we are likely to soon see a sharp rebound in emissions as economic conditions improve,” he says.

Whether lasting changes to our global energy sources are made will depend, in large part, on the decisions governments make now, he adds: if governments put clean energy at the heart of their visions for rebuilding economies and keep renewables on track for further growth.

More must-read energy sector coverage from Fortune:

—Why the coronavirus crisis could make Big Oil greener
—How Global 500 companies are responding to the coronavirus
—The oil industry is running out of storage for its unprecedented surplus
—The Church of England is going up against ExxonMobil on climate change. Can it win?
—Listen to Leadership Next, a Fortune podcast examining the evolving role of CEO
—WATCH: Why the coronavirus crisis could make Big Oil greener

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