Ask a cloud AI a question and a building somewhere answers it. That building is full of computers, it runs on electricity, and it is kept cool by evaporating fresh water. Thousands more are going up right now, often next to ordinary neighbourhoods. Here are the real numbers, mostly from the companies themselves, including the ones that make us look bad.
These buildings are the fastest growing electricity users on earth, they drink water from real local reservoirs, and the people living nearby carry most of the side effects.
GreenCube answers on your own laptop instead. No cooling tower runs for your question, and nobody puts up a new building because you asked one.
What we will not claim: your laptop is not the greener option. It uses more electricity per answer than their hardware does. The honest version of that is further down, and we have not hidden it.
These come from the International Energy Agency. Not campaigners: the careful people whose job is counting the world's electricity.
These buildings will use double the electricity in 2030 that they used in 2024.
Every plug, every light, every factory on Earth. These buildings take 1.5% of it today. Nearly 3% by 2030.
Their power use grows about 15% a year. Everything else on the grid grows four times slower.
We didn't dig this up. They printed it themselves, in their own yearly reports, about themselves.
Four years left on that promise, and they're going the wrong way.
Running them got 2% cleaner. Building them got a lot dirtier.
One building drinks
like a small town.
Electricity is hard to picture. Water isn't. It comes out of a real reservoir, next to real people. Cooling the computers boils it away, so it never comes back.
A day. For one big building. That's as much water as a town of 10,000 to 50,000 people uses.
A day, for all the US ones together. And that was back in 2021, before the AI rush even started.
Ask a cloud AI for a 100-word answer and that's roughly one small bottle of water, boiled away.
Boiled away just teaching GPT-3 to talk. That is the same fresh water it takes to build 370 BMWs.
Power and water are the two everyone talks about. The World Resources Institute went through the rest of it: what actually changes for the people whose street one of these gets built on.
One modern AI building can use as much power as 100,000 homes, and the big ones being built now are planned for up to twenty times that. In 2025 American households paid about 10% more for electricity than the year before. The causes are tangled, but in at least one region the cost of building new supply for data centres was part of it.
A mid sized building can drink 300,000 gallons a day and a large one up to 5 million. Two thirds of everything built or planned since 2022 sits in places that are already short of water.
Backup generators run on diesel and emit 200 to 600 times more nitrogen oxides than a gas plant. One study in Virginia put the health cost of even occasional use at roughly $300 million a year.
Cooling systems and generators run at 85 to 100 decibels, which is a motorbike or a jackhammer, sometimes for days at a time. Residents in Loudoun County reported headaches and broken sleep.
The average site reached about 224 acres in 2024, roughly 450 football pitches, and up 144% in two years. The biggest campuses pass 1,000 acres, usually on farmland.
This is the part that surprises people. Construction employs hundreds, but once it opens, even the largest sites employ fewer than 150 people, sometimes as few as 25.
We sell AI that runs on your computer. So it would suit us to finish this page with "…and that's why the cloud is killing the planet." But that isn't true. And if we lied to you here, you'd be right to stop believing everything above it.
The same report says these buildings will still only be about 3% of the world's electricity in 2030. Planes, cement, steel and cows are all far bigger problems. Anyone telling you AI is the main villain here is selling you something.
And one more, about us. Your laptop is not the greener choice. It actually burns more electricity to answer you than their building would, because their chips are built for this and yours are not. Researchers measured it: theirs get between 1.6 and 7.4 times more work out of the same electricity.
So here is all we'll claim, and it's true: nobody boils off a town's drinking water to answer your question, and nobody puts up a new warehouse because you asked one. Your computer is already here, and it's already switched on.
Sources: IEA · “Intelligence per Watt”, arXiv 2511.07885.
The full numbers, why credible researchers disagree about them, and what actually reduces it.
Read the answer → The other costWater and power are one price you pay. Your private chats are the other one, and you pay that every time you type.
See what stays on your machine →