Data centre debate heats up ahead of US midterms – here's what you need to know

ByDaniel Thomas and the Visual Journalism Team.

Key points

• This year, the tech industry is projected to spend a combined $765bn, external ($544bn) on AI infrastructure in 2026, with this topping $1tn next year.
• There are regarding 12, 250 data centres worldwide, according to Data Center Map, external, a business that tracks both operational and pre-operational sites.
• When there were around 8, 000, external operational sites, that's up sharply from 2021.
• For instance, Colossus 2, which is part of the wider Colossus campus, will house hundreds of thousands of advanced AI chips created by tech giant Nvidia.
• Extra reporting and design by Erwan Rivault, Matt Faraci and Dominic Bailey.

Until a few years ago plenty of of us may have been blissfully unaware of what a data centre was.

These giant, warehouse-like buildings power virtually all our internet activity, from our web searches and emails to movie downloads and online banking.

They are at the heart of the AI boom, housing the advanced computer chips and servers needed to run services like ChatGPT and Claude.

But the speed at which they're growing, the enormous amount of electricity they consume and reservations concerning their environmental impact are fuelling a public backlash worldwide.

In the US, they've become a massive problem ahead of the midterm elections on 3 November, with both Republicans and opposition Democrats coming out against their development.

It's putting opponents of data centre expansion on a collision course with US President Donald Trump. This person has dismissed the pushback as a "sick conspiracy", even as public anger grows.

Here's what you need to know regarding the data centre boom, and why opposition is growing. They are growing rapidly.

As the chart below demonstrates, data centres are most densely clustered in the US which has 4, 767 sites. It is followed by Europe, where the UK and Germany lead.

Data centres have typically been located near to cities where it's easier to access high voltage power lines or water resources for cooling. But as they obtain bigger, more are being built in rural areas.

But when it comes to actual capacity, the US is ahead by a much larger margin, with China in second place and Europe lagging far behind.

This gap is due to widen in the coming years, leading some to warn Europe risks missing out on the potential economic benefits of the AI boom, external. They are getting bigger.

Data centres vary wildly in size, ranging from ones that fit inside a garden shed to others covering vast expanses of land.

Notably, the world's largest operational data centre is widely documented to be one run by China Telecom in Hohhot, Inner Mongolia, covering an area of approximately one million square metres (10.7 million sq ft). That is equivalent to regarding 140 Fifa football pitches.

Nevertheless, much larger sites are under construction as the graphic below indicates.

All these sites are being built exclusively to provide the immense computing power needed to run AI services.

It will additionally be employed to train xAI's chatbot Grok. Elon Musk's firm will apply 41 methane gas turbines to support power the site. It activists say could "significantly increase" local air pollution, external. Local regulators say the turbines will meet air quality standards. They employ more electricity than France.

Notably, the pressure data centres put on local resources has sparked increasing concern. These facilities can employ significant amounts of water to cool their systems. It could lead to water shortages, some experts say.

As the chart below indicates, data centres worldwide are additionally thought to consume more electricity than the whole of France.

This growing hunger for power is driving up carbon emissions, analysis demonstrates, while putting pressure on local grids. It some fear could push up energy costs.

With others worried regarding the noise data centres produce and the space they take up, a public backlash is gathering steam.

Some 16 US states have proposed laws to ban or temporarily block new facilities, and it could be a key matter in November's midterm elections.

Outside the US, opposition to data centres has emerged in countries like Mexico, France, Indonesia and the UK. But they can boost jobs.

But supporters say data centres are critical to national security, and the development of AI.

They additionally say they are good for the economy, external, attracting investment, generating tax revenue and creating jobs in areas like construction.

Although fewer than industry advocates claim, a recent report by the Brookings Center, external suggests data centres do create local jobs.

Notably, the type of data centre matters too. So-called hyperscale facilities – massive sites owned and run by tech giants like Amazon and Microsoft – have a bigger positive effect on jobs, it discovered.

But "colocation" facilities, which lease space to remote tenants without a local presence, brought fewer benefits.

As the debate over their merits intensifies, the data centre rollout continues.

But as reservations concerning the environmental impact grow, the tech industry is exploring alternatives.

One idea is to put data centres in space, external or on the Moon, where they could harness abundant solar energy.

Others predict that more AI processing could eventually be carried out by the hardware already inside our computers and smartphones, reducing the need for vast data centres altogether.

Taken together, the developments around data centre debate heats up ahead of US midterms – here' s what point to a situation that is still moving, and the coming days should bring more clarity.