Microsoft’s greenhouse gas pollution increased by about 25 percent last year, the company said in a recent sustainability report released Thursday.
The report follows similar reports published by Google and Amazon last week. Together, they show a disturbing trend of rising greenhouse gas emissions from tech companies, fueled by the global race to build energy-hungry data centers.
In blog entry In announcing the report, Microsoft vice president and president Brad Smith and chief sustainability officer Melanie Nakagawa say the boost in emissions is “primarily due to the expansion of our data center infrastructure.”
They write that much of this boost was linked to greenhouse gas emissions from energy purchased or acquired by the company to run its business. Greenhouse gas pollution, known as Scope 2 emissions, accounted for 13 percent of Microsoft’s total emissions.
Data centers that exploit vast volumes of power-hungry artificial intelligence chips have over the past few years pushed the net-zero energy goals of many vast tech companies increasingly out of reach.
Amazon revealed a 16 percent boost in CO emissions2 emissions in its latest sustainability report. Google he said in its recent sustainability report shows that annual greenhouse gas emissions increased by 18 percent last year compared to 2024, the largest single-year increase it’s recorded. The company has been investing aggressively in renewable energy, but has also started powering some of its data centers with fossil fuels.
Microsoft highlighted in its sustainability report that it covered 100 percent of its electricity consumption with zero-emission sources. However, data center expansion will accelerate, and some of Microsoft’s recent investments could boost greenhouse gas emissions. It’s worth noting that the recent report covers fiscal year 2025, which ended last June, and since then there have been a number of deals involving gas-powered data centers.
Last month, the company formally announced a partnership with Chevron, which is building a plant to power a future data center for the company in West Texas. Permits show that this power plant could have emitted over 11.5 million tons of CO2 equivalent per year, an amount greater than for the entire state of Rhode Island. The company has also leased buildings on its Stargate campus in Abilene, Texas, which will be powered by an on-site power plant that can emit more than 7.8 million tons of CO2 equivalent every year. Microsoft also signed a non-binding letter of intent for computing at a data center in West Virginia that will be powered by off-grid gas that could emit over 11 million tons of greenhouse gases.
“Microsoft’s strategy is to explore various options to reduce emissions from electricity consumption, consistent with our sustainability ambitions,” Nakagawa says in a statement to WIRED.
Microsoft’s approach to offsetting some of its emissions through loans and other investments is also changing. The company says it has stopped purchasing unbundled renewable energy certificates, which partially contributed to the boost in Scope 2 emissions. The exploit of these types of certificates was criticized in recent years as greenwashing because they don’t necessarily add more spotless energy to the grid. Decoupled RECs are essentially “a paper transaction, physically separated from real-world consequences,” says Danny Cullenward, a researcher at the University of Pennsylvania. (Cullenward is also a guest lecturer at Google, but notes that he has not spoken on behalf of the company.)
“I think it’s commendable [Microsoft] “moves away from unbundled RECs and prioritizes investments in new clean electricity where power purchase agreements and other long-term offtake agreements can bring new clean electricity into the grid,” he adds.
Despite rising emissions and continued investment in AI, Microsoft still says it plans to become “carbon negative” by 2030. Smith and Nakagawa write that the global race for AI is “increasing demand for… energy, water, land and materials.” They argue that the company “has a responsibility to help ensure that technology strengthens, rather than burdens, the systems and communities on which it depends.”