Microsoft's emissions up 29 per cent on construction
On 15 May 2024 Microsoft published its environmental report for financial year 2023. Direct emissions and those from purchased energy fell 6.3 per cent against the 2020 baseline, but supply chain emissions rose 30.9 per cent and the aggregate across all categories rose 29.1 per cent. The cause is named outright: building data centres, and the carbon embodied in concrete, steel, semiconductors, servers and racks.
Why it matters
A company that committed in 2020 to being carbon negative by 2030 showed that its own construction was moving the other way. What matters is not the number itself but what it points at: not the electricity the servers draw, but the materials the halls that hold those servers are made of.
The supply chain accounts for over 96 per cent of the company's emissions, so the 30.9 per cent in that category is what sets the aggregate. The report also states that new data centres are designed to consume no water at all for cooling. Emissions from purchased energy are reported on a market basis - against the annual volume of certificates bought, not against the hourly load. That is why a 6.3 per cent fall and a 30.9 per cent rise appear in the same report without contradicting each other. What the record does not claim. There is no water use effectiveness of 0.30 litres per kilowatt-hour in the report: the strings 0.30 and WUE occur in it zero times. Nor is there an August 2024 date for the switch to closed-loop cooling. Both numbers were attributed to the report from outside.