Microsoft’s greenhouse gas emissions increased nearly 25 percent last year, the company said in its new sustainability report released Thursday.
The report follows similar ones released by Google and Amazon last week. Together, they reflect a troubling trend of rising technology company product launches, driven by a global race to build power-hungry data centers.
In a blog post announcing the report, Microsoft vice chairman and president Brad Smith and chief sustainability officer Melanie Nakagawa attributed the increase in emissions to “primarily the expansion of our data infrastructure.”
They wrote that a large part of that increase was related to outsourcing that the company bought or acquired to run its operations. Known as Scope 2 emissions, those greenhouse gas emissions account for 13 percent of Microsoft’s total.
Data centers, which consume large amounts of power using artificial intelligence chips, have pushed the goals of large technology companies out of reach in the past few years.
Amazon revealed a 16 percent increase in its CO2 carbon emissions in its latest sustainability report. Google said in its new sustainability report that annual greenhouse gas emissions rose 18 percent last year compared to 2024, the largest single-year increase on record. The company has invested heavily in renewable energy, but has also begun adding fossil fuel power to some of its data centers.
Microsoft highlighted in its sustainability report that it matches 100 percent of its electricity consumption with carbon-free sources. But data center construction is set to accelerate—and some of Microsoft’s latest investments could boost its output. Notably, the new report covers fiscal year 2025, which ended last June, and has made several deals since then involving gas-powered data centers.
Last month, the company officially announced a partnership with Chevron, which is building a power plant to power the company’s future data center in West Texas. Permits show that power plant could emit more than 11.5 million tons of CO2 equivalent annually, an amount greater than the entire state of Rhode Island. The company has also leased buildings for the Stargate campus in Abilene, Texas, which will be powered by an on-site power plant that will emit more than 7.8 million tons of CO.2 equivalent each year. Microsoft also signed a non-binding letter of intent to compute at a West Virginia data center, which will be powered by off-grid gas that would emit more than 11 million tons of greenhouse gases.
“Microsoft’s strategy includes exploring a variety of ways to reduce emissions from its electricity use, in line with our sustainability ambitions,” Nakagawa said in a statement to WIRED.
Microsoft’s approach to reducing some of its emissions through credits and other investments is also changing. The company says it has stopped buying non-bundled renewable energy certificates, a move that has contributed to the increase in Scope 2 emissions. Using these types of certificates has been criticized in recent years as greenwashing because it doesn’t really add clean energy to the grid. Unbundled RECs are essentially “paperwork that’s physically disconnected from real-world results,” said Danny Cullenward, a researcher at the University of Pennsylvania. (Cullenward is also a visiting faculty member at Google but notes that he was not speaking for the company.)
“I think that is very admirable [Microsoft] it moves away from unbundled RECs and prioritizes investments in new clean electricity, where power purchase agreements and other long-term off-take agreements can create and bring new clean electricity online,” he adds.
Despite rising emissions and its continued investment in AI, Microsoft still says it plans to be “carbon negative” by 2030. Smith and Nakagawa write that the global race for AI is “increasing demand for … energy, water, land, and building materials.” They say the company “has a responsibility to help ensure that technology strengthens, rather than depresses, the systems and communities that rely on it.”
