Why Don’t Data Centers Use More Green Energy?

Sept. 29, 2025

 

It’s been a big week for A.I. data centers. That means it’s also been a big week for coal and natural gas.

Nvidia this week announced a $100 billion investment to support OpenAI’s enormous build-out of data centers that use its chips. The next day, OpenAI said it had signed deals with SoftBank and Oracle to build five new data centers as part of the Stargate Project, a $500 billion plan for A.I. infrastructure. (The three companies unveiled it at the White House back in January.)

The announcements are the latest in a global push to speed the construction of A.I. data centers. OpenAI, Amazon, Google, Meta and Microsoft are together spending more than $325 billion on them by the end of the year. To stay on the bleeding edge, the companies want the latest processors, cooling systems, facilities — all running 24/7 on mind-bending quanta of electricity.

In the U.S., more than half of that power is coming from fossil fuels.

President Trump, who called green energy a “scam” at the U.N. General Assembly this week, has enthusiastically endorsed natural gas, coal and oil. He has also subsidized them. As part of his official A.I. plan, he pledged to scrap “radical climate dogma and bureaucratic red tape” and fast-track fossil fuel projects instead.

But there are reasons beyond politics that help explain why smog-spewing fossil fuels have become the go-to power source for futuristic data centers. The pairing is almost unavoidable — at least for now.

Renewables

Sprawling solar farms, windmills and hydroelectric dams are the best energy options for the planet, and usually the cheapest. [Huh?] Their economic upside has made them, collectively, the fastest-growing power source for data centers worldwide.

But renewables often can’t shoulder the load alone, despite being a major part of the A.I. power plan. That’s because servers hum and whir around the clock — not just when the sun is up or the wind is blowing. They demand a constant, stable flow of electricity. If power falters, even for a few seconds, companies lose thousands of dollars, sometimes more.

There’s a fix: Companies can pair solar and wind farms with massive batteries that store power and then release it in a steady stream. But storing energy that way is relatively pricey and may still fall short of providing the nonstop energy that data centers need. “Batteries are a great way to shift daytime electricity to evening electricity — but not a great way to shift July electricity to January electricity,” said Matthew Bunn, a professor at Harvard who studies energy policy. So even the greenest facilities rely on fossil fuels or the local grid for backup, he told DealBook.

Another challenge: The biggest data center campuses will consume multiple gigawatts of power. (As part of this week’s deal, OpenAI agreed to use Nvidia chips in at least 10 gigawatts’ worth of data centers.) To continuously produce just a single gigawatt, a renewable-energy plant would need around 12.5 million solar panels — enough to cover nearly 5,000 football fields. Wind turbines would need even more room. Many data centers near cities and towns don’t have that kind of space.

Nuclear

That’s where nuclear plants come in. They have smaller footprints, generate steady power and, like renewables, emit no carbon.

But they’re expensive. That’s why the nuclear industry has been in a decades-long rut. It boomed back in the 1970s, when the global energy crisis quadrupled oil prices. But Americans’ enthusiasm for nuclear energy soured after a series of headline-grabbing accidents, like the 1979 partial meltdown at Three Mile Island.

Around the same time, our electricity needs started to decline — which tends to happen in mature economies. Oil prices came down, so we stopped building nuclear reactors.

The industry has been groping for a good sales pitch ever since. With A.I., it finally has one: Energy demand is soaring, and nuclear companies can help fill the gap.

A slight snag: They’ll need another seven or eight years to do it, best-case scenario, said Jacopo Buongiorno, a nuclear science professor at M.I.T. That’s how long it takes to build new nuclear plants.

So, it’s a gamble: Tech companies investing in nuclear power (Microsoft, Google and Amazon, among others) are betting billions that A.I. demand will continue to rise a decade from now, when those nuclear facilities open for business. But it’s not clear their bets will pan out.

Fossil Fuels

The U.S. has vast natural gas reserves in underground reservoirs and offshore deposits, so it’s cheap and available. And the infrastructure to harness it can be ready fast: “A year or two, and you have a gas plant,” Buongiorno said.

If data centers continue expanding at their going rate, their energy needs will far surpass the current supply by 2030. So tech companies that need to bridge that widening gap are reaching for fossil fuels. Natural gas is already the top power source for U.S. data centers, according to the International Energy Agency, and it’s on track to dominate through at least 2030.

The only other energy source that can be deployed in one to two years — aligning with the construction timeline for most data centers — is solar, which has its own drawbacks.

 

Credit...The New York Times

Trump’s policies are only making natural gas more attractive. The administration was already subsidizing fossil fuels, and now it’s eliminating regulations and green-energy tax credits to bolster them further. President Trump says the new policies will help American companies develop A.I. tools unencumbered by pesky rules and oversight. Climate advocates say he’s stacking the deck for the fossil lobby.

His plan may work. It may also accelerate climate change by pumping heat-trapping gases into an atmosphere already at its highest-recorded temperature ever. For now, though, tech companies are seeing an opportunity to invest.

Why Don’t Data Centers Use More Green Energy? - The New York Times