A warning sign about the true cost of AI, courtesy of Google and Amazon

It’s no secret that AI is a hog, consuming energy and water like no other digital technology before it. We now know how much Big Tech’s pursuit of AI is costing the environment.

Both Google and Amazon released their sustainability reports this week, and the numbers are not good. Each company has promised to eliminate its carbon emissions in the coming years, but AI has made those goals more difficult to achieve. Google’s total carbon emissions increased by 25% from last year, Amazon’s increased by 16%.

A close reading of the reports suggests that both Amazon and Google will have to make serious, and potentially expensive, changes to their businesses if they are to achieve their net-zero goals.

No company has come out and directly blamed AI for the rise in gas, but there is plenty of circumstantial evidence.

AI is at the center of everything

Both Amazon and Google admit that their energy consumption has increased significantly in the past year as the use of AI has increased. Both refer to carbon intensity — essentially, how much pollution a company produces for each dollar of revenue — a metric China has used in the past few years when negotiating climate deals as its emissions soared. And both spend a few pages showing how AI can benefit nature, a case of “too much protest,” to borrow some Shakespeare.

The picture becomes clearer the deeper you dig into the data. Both companies are actually doing OK when it comes to air pollution from energy purchases. Years of buying renewable energy have helped keep a lid on things, though that may change in the near future as tech companies, including Google, have begun investing heavily in natural gas power plants to keep up with AI’s power needs.

Instead, Amazon and Google’s carbon footprint comes from so-called Scope 3 emissions – a catch-all category that covers pollution by a company that it doesn’t directly control, such as the goods and services it buys or the products it sells. For companies like Amazon and Google, Scope 3 includes things like GPU purchases and use of the company’s products, such as phones and tablets.

Google includes two categories of Scope 3 emissions – capital goods and consumer goods – although it admits the latter is small enough to be impractical. (Most of Google’s hardware products are small devices that don’t use a lot of electricity.) That probably leaves data centers as the main driver. Last year, Google’s Scope 3 emissions increased by 2.1 million metric tons, which means it is now double what it was in 2019, the year Google uses as its baseline when evaluating its performance.

Amazon’s rising Scope 3 emissions are mostly from commodities and fuel and energy. The former would include data centers and warehouses, which could help explain why Amazon’s Scope 3 rollout is higher than Google’s. However, a good chunk is probably data centers. “To meet strong customer demand, by 2025 we added more data center capacity globally than any other company, including more than 1.2 gigawatt (GW) in Q4 alone,” Amazon wrote in the report.

Hitting the wall

That kind of spending helps explain why decarbonization is suddenly so difficult. For many years, the biggest contributor to their carbon footprint was the power of modest-sized offices and data centers. That could easily be canceled to buy renewable energy.

AI has stepped that way. While technology companies still use renewables and batteries to power their data centers, they are starting to switch back to fossil fuels. It’s a practice that will make their zero-sum promises very difficult to deliver, but they are irreversible.

The most dangerous emissions come from the design and installation of the data centers themselves. The steel and cement industries are both heavy polluters, and while startups are working on low-to-zero carbon solutions, they are not yet ready to deliver on the scale required by tech companies.

Then there are the GPUs and memory chips that are powering the AI ​​boom. Producing semiconductors uses a lot of energy, and many of the world’s leading factories are located in Asia, where power grids remain fueled by fossil fuels. To make matters worse, many of the chemicals used in those factories are also powerful greenhouse gases, capable of warming the atmosphere thousands of times more than an equivalent amount of CO2. Indulging in chips is likely to increase the carbon footprints of Amazon and Google.

None of these problems are insurmountable, although Amazon, Google, and their peers have their work cut out for them. To fulfill their net-zero pledges, they will need to increase their purchases of renewable energy, invest heavily in improved steel and cement production, and buy many millions of tons of carbon credits. It’s still possible, but their adoption of AI hasn’t made it any easier.