Microsoft’s greenhouse gas pollution jumped roughly 25% last year.
The number lands squarely in the company’s latest sustainability report. It came out Thursday. Google and Amazon dropped theirs last week. Together the reports sketch a messy picture. The race for data center power is sucking the air.
Brad Smith, the vice chair, and Melanie Nakagawa, chief sustainability officer, didn’t sugarcoat it in a blog post. They said the spike was “primarily driven by the expansion of our datacenter AI infrastructure.”
That phrase carries weight. AI chips are hungry beasts. They demand constant power. Most of this new pollution comes from Scope 2 emissions. This is the gas generated by electricity the company bought. It accounts for 13% of Microsoft’s total footprint.
Other tech giants are bleeding red ink on their green promises too. Amazon saw CO2 climb 16%. Google’s emissions rose 18% last year over 2024. It was their biggest single-year jump. They bought renewables aggressively but they also started adding fossil fuel plants. Why? Because grids can’t keep up.
“Data centers… have pushed many large tech companies’ coverage increasingly out of reach.”
Microsoft insists it matched 100% of its electricity use with carbon-free sources this fiscal year. That sounds good until you look closer. The data center buildout is accelerating fast. Some new deals might spike emissions further. The current report covers the 2024 fiscal year, ending June 30. Since then, they have signed new contracts involving gas-powered sites.
Take last month. Microsoft teamed up with Chevron for a new plant in West Texas. Per suggest this one facility could pump out more than 11.5 megatons of CO2 equivalents a year. That exceeds Rhode Island’s entire emissions.
Then there is Abilene, Texas. They leased buildings at the Stargate campus. The onsite power plant could emit another 7.8 megatons annually. A West Virginia site added a non-binding agreement for off-grid gas compute. Another 11 megatons potentially entering the mix.
Nakagawa told WIRED that the strategy includes exploring various options to mitigate these hits. She claims it aligns with sustainability goals.
The method of mitigation itself has changed, though. Microsoft stopped buying unbundled renewable energy certificates. Those paper credits used to prop up Scope 2 numbers. Critics called it greenwashing. Danny Cullenward, a University of Pennsylvania researcher, calls unbundled RECs a “paper transaction… physically disconnected from real-world consequences.” He works as a visiting faculty at Google but insists this opinion is his own.
“I think it’s highly commendable [Microsoft is] moving away… and prioritizing investments in new, clean electricity.”
So does this mean the sky is falling. Not entirely. Microsoft still targets “carbon negative” status by 2030, even as the global AI boom drives up demand for land, water and power. Smith and Nakagaka write that they have a duty to strengthen, rather strain, the systems they rely on.
Words are cheap, however. The Texas heat rises regardless of what is written in a blog post.
