Microsoft, Amazon and Google’s collective carbon emissions have surged by nearly a fifth in the past year, reaching 119 million metric tonnes of carbon dioxide equivalent (mTCO₂e) in the financial year ending March 2026, according to their annual sustainability reports. This figure is roughly a third of France’s total emissions. The previous year, the three tech companies emitted about 101 million mTCO₂e, comparable to Czechia’s 2024 emissions.
AI and cloud services drive emissions growth
The increase is largely attributed to a boom in demand for cloud services, including data storage and server operations, linked to training and running chatbots and other AI products. Microsoft’s emissions rose 25% to 20 million mTCO₂e, driven primarily by datacentre infrastructure expansion. Google’s emissions increased 18%, citing supply chain activities supporting rapid business expansion, though the company claims its AI systems helped reduce emissions elsewhere by 41 million tonnes of CO₂ last year. Amazon reported a 16% overall emissions increase and a 20% rise in supply chain emissions, including datacentre construction, while still framing this as progress toward its 2040 net-zero goal.
Criticism of green marketing claims
Cecilia Rikap, an economics professor at University College London, said: “Claims by Microsoft, Amazon and Google about their clouds being ecologically friendly and sustainable are a marketing strategy. Governments should remember these expanding carbon footprints when the very same companies offer addressing the ecological crisis with AI solutions.” She added that companies migrating to the cloud are outsourcing their digital and AI carbon footprint to these giants, obscuring their own environmental impact.
Massive investment in AI infrastructure
The world’s biggest tech companies are on track to spend $765 billion (£570 billion) this year, mostly on building AI datacentres worldwide, from Norway to North Tyneside. This marks a sharp reversal from years of emissions reduction efforts. Prior to this year, Microsoft’s emissions had flatlined at 16 million mTCO₂e in 2023 and 2024. All three companies still aim for net zero: Google and Microsoft by 2030, Amazon by 2040.
Carbon credit shortages and power demands
Shaolei Ren, a professor of electrical engineering at the University of California, Riverside, noted that Microsoft’s sustainability report indicated fewer carbon credits available globally to offset emissions. “While companies are actively investing in or purchasing carbon credits, the figure suggests a possible lack of credit supply in the carbon market to meet the technology companies’ needs,” he said. “Everyone is talking about the lack of physical goods and infrastructure like power, but there may also be a lack of virtual goods – carbon credits.”
The datacentre boom is accompanied by vast projected power demands. The Uptime Institute estimates that big datacentre projects announced last year would consume 1.3% of the world’s electricity usage, nearly doubling current datacentre demand, with most new demand coming from US projects. JLL, a US property consultancy, expects about 1,200 datacentres to be built globally by 2030, driven overwhelmingly by AI.
