Why are data centres such a big deal in Scotland?

Every time you ask ChatGPT a question, read a Google summary or make an online bank payment, a data centre is working behind the scenes. Now Scotland is part of a global race to build many more of them - on a massive scale. The explosion in artificial intelligence (AI) over the past few years has seen tech firms scrambling to build new "hyperscale" data centres, including some which would rank among the biggest in the world.

Plans are in place to build at least 23 giant AI-powered data centres. Supporters say they are vital for the future and could bring billions of pounds in investment, as well as thousands of jobs. Opponents fear the impact of their size on local communities, the vast amounts of energy they use and even the noise they will make.

So what exactly are data centres, and why have they become one of Scotland's most controversial planning battles? From the outside, data centres look like a factory or a warehouse. On the inside, thousands of flashing lights blink and fans whirr as rows of computer servers power AI.

While some are built by tech giants like Amazon, other developers claim commercial sensitivities when asked what they are actually powering. Scotland's centres are currently quite small, but some of proposals for the hyperscale versions are immense. One of the biggest is at Auchtertool in Fife.

The site would span 60 hectares (150 acres) - about the size of 84 football pitches. AI is seen by some as the most transformative technology ever made but others have warned there is chance that if the frightening pace of development continues it "could kill all humans" within the next decade. But Scotland's data centre debate is not really about the technology inside the building - it's about the scale and impact of the centres themselves.

At the moment, the biggest data centre in Scotland is thought to be DataVita's site in Airdrie, which has a capacity for 12MW. The new data centres being proposed are a whole new level. If one planned for Chapelcross in Dumfries and Galloway goes ahead, it will have a capacity of 1,000MW - making it one of the largest data centres in the world.