Microsoft promised to be carbon negative. Its emissions just jumped 25%

Microsoft promised to be carbon negative by 2030. Its own report shows emissions up 25% in a year instead. The number is worse than it looks, and also more honest than it looks, and the reason for both is the same: AI data centres.

Microsoft set one of the boldest climate targets in tech. By 2030, it said, it would remove more carbon than it emits. Its 2026 sustainability report shows the company moving the other way.

Greenhouse-gas emissions rose 25.1% in the last financial year, from 16.2 million tonnes to 20.3 million, as TechRadar noted from the filing. That is roughly 58% above the 2020 baseline Microsoft set when it made the pledge.

Why the jump is partly honesty

Not all of that rise is fresh pollution. Microsoft has stopped buying short-term renewable-energy certificates that do not add real clean power to the grid. Those credits had flattered last year’s figure. Strip them out, and the true number climbs.

You can see it in one line. Scope 2 emissions, the ones from bought electricity, jumped from 1.6% of the total to 13.3% in a single year. That is the accounting catching up with the data centres.

The rest is real growth. Microsoft is building AI and cloud capacity at speed, and each site needs power, steel, and concrete. Its diesel and crude-oil use rose 51%, even as it cut natural gas and petrol.

The progress it wants you to see

Microsoft is not only pointing at the bad number. It says the figure would have been closer to 34 million tonnes without its efficiency work and clean-power deals.

It also matched 100% of its annual electricity use with renewable energy, put back more water than it took, over 14 million cubic metres, and reused or recycled 92% of its retired servers. “Innovation at this scale must be matched by responsibility at the same scale,” wrote chief sustainability officer Melanie Nakagawa.

All of that is real. It is also beside the point of the headline. The pledge was a hard target with a date, and the line is pointing the wrong way.

The maths of the pledge

That is the tension of the AI boom, written into one accounts line. The technology Microsoft is betting its future on is the same thing wrecking its climate maths.

The company has poured money into carbon removal and mass-timber buildings, and signed some of the largest clean-power deals in the industry. None of it is scaling as fast as the data centres are rising. The deadline is four years away.

Everyone’s number is moving

Microsoft is not alone. Amazon’s emissions rose 16% last year, and Google’s climbed about 25%, both blaming AI. Meta’s Hyperion campus ballooned past $50bn and split a Louisiana town. The build-out has triggered the largest gas-plant boom in history, pushed power bills up across the Rust Belt, and helped make New York the first state to freeze new sites. Some firms are even trying to float data centres out to sea.

The industry keeps promising the efficiency curve will bend the line back down. Microsoft has the money and the will to prove it. For now, its own report shows the line still climbing, and the clock still running.