I happened to spend much of this week in Abu Dhabi, from whence came, conveniently, the most important news of this week, month, year, and arguably decade. Yes, bigger than the American election; yes, bigger than the long-awaited rise of machine learning; yes, bigger than Elon Musk’s one-two punch of space travel and electric cars — although it’s related to that.

I refer of course to what Ramez Naam elegantly describes as: “the cheapest contract for electricity ever signed, anywhere on planet earth, using any technology.” And what is the source of this unbelievably inexpensive energy, here in this oil-soaked nation of the United Arab Emirates, on the edge of the Persian Gulf, home to a full fifth of all the world’s oil?

Yep, you guessed it: solar power. Unsubsidized solar power.

Go read that Naam piece in its entirety, and consider its ramifications. Calling the ongoing plunge in solar-power prices “remarkable” would be far too conservative. Let’s go with the word it deserves: “revolutionary.”

As The Economist observes, the price of solar power has dropped by 80% in the last six years. Eighty percent! Meanwhile, thanks to Tesla, GM, and every other car company worth their molten salt, “electricity generation” is finally beginning to slowly — but inexorably — become a synonym for “vehicle propulsion.”

But the key question is: how slowly? It now seems apparent that we will wean ourselves off fossil fuels well before we ever run out of them. But that’s not enough; the cliff we’re racing towards is much closer than that.

As the New Republic says, if we want to avoid catastrophic climate change, “we’ll need to close all of the coal mines and some of the oil and gas fields we’re currently operating long before they’re exhausted.”

Will ever-cheaper solar (and wind) power be enough to make that possible? Probably not. We’ll need breakthroughs in energy storage, as well as energy generation. (And, at least possibly, a significant increase in nuclear power generation.)

There are multiple dramatic ironies here. One, of course, is that the petrostates of the Gulf now find themselves on the forefront of renewable power generation:

…and another is that we’re in a race between the sun broiling our civilization until it’s unrecognizable, and the sun saving us from that fate.

This is not the first, or the greatest, self-imposed threat that we have collectively faced — that would be the prospect of nuclear annihilation during the Cold War — but it’s arguably the trickiest. Still, I find reasons to be cheerful. After all, cheap solar power means it’s raining donuts; a long-run world wherein most power usage comes without long-term tragedy-of-the-commons trade-offs is at least plausible.

Most of all, consider the symbolism of the source of this week’s news. If even the United Arab Emirates can re-tool for solar energy, and slowly transform itself from a nation built on oil wells to one that runs on on investment, trade, and immigration — then surely the rest of us can too.