The battered sign outside the disused nuclear power plant in PennsylvaniaA US state with a population of nearly 13 million. tells a terrifying story. In 1979, Three Mile Island was the scene of the nation's worst commercial nuclear accident:

"Radiation was released, a part of the nuclear core was damaged, and thousands of residents evacuated the area."

Once the plant was shut down, most people assumed it was gone forever. But a few weeks ago came the news that it was to reopen in 2028. It will power Microsoft's centres for storing data.

Data centres need a huge amount of electricity. This is expected to more than double by 2030, thanks to the demands of AI.¹

Meanwhile, tech companies are under pressure to cut carbon emissions. Nuclear power is seen as a way of producing extra electricity cleanly, in spite of its risks.

In an article for The Guardian, Chris Stokel-Walker set about trying to work out how much data the average person uses, and their resulting carbon footprintThe total amount of greenhouse gases (including carbon dioxide and methane) that are generated by our actions. China is the top emitter with 28% of the world's total emissions. The US is second with 14%..

The carbon dioxide emissions generated by sending just one email are around 17g, and a 2020 analysis by the International Energy Agency (IEA) found that watching an hour of Netflix was equivalent in emissions terms to boiling a kettle, producing about 36g of CO₂.

According to the UK's Department of Transport, the average car produces 0.2kg of carbon emissions per mile. Making 50 searches on Google every day for a year, would produce the same emissions as driving for 39 miles; playing Fortnite for an hour a day for a year would be equivalent to driving for at least 71 miles; but streaming an HD film for an hour a day for a year would produce the same emissions as driving for 4,745 miles.

Should we go on data diets?

Yes: It is mad to use as much data as we do when we are supposed to be reducing the world's energy consumption. Nuclear power may be a clean source of electricity, but it is not always safe.  

No: The amount of data that we use as individuals is tiny compared to the demands of governments and big business. Sending fewer texts or emails will not make any difference to anything.

Or... If AI becomes as clever as its inventors think it can, it will recognise that its massive energy use is a threat to the environment and turn itself off without humans having to make a decision.