The AI boom tests the limits of growth

Electricity demand is becoming the clearest measure of the AI industry's extraordinary expansion — and a test of how long that pace can last.

Why it matters: The industry's pursuit of ever-larger models is fueling debate over whether they will deliver enough value to justify mounting environmental and financial costs.

Driving the news: Google, Microsoft and Amazon all highlighted improved energy and water efficiency in sustainability reports released in recent weeks.

• But those gains are being overwhelmed by overall growth.

Stunning stat: Google's electricity consumption rose more than 140% between 2021 and 2025 — already exceeding the outer bounds of projected growth modeled in a 2023 paper by Alex de Vries-Gao, a researcher at VU Amsterdam and founder of online platform Digiconomist.

By the numbers: That scale of growth is across the board.

• De Vries-Gao estimates that the amount of new combined electricity demand added by Google, Microsoft, Amazon and Meta between 2022 and 2025 is roughly twice New York City's annual electricity consumption.

Between the lines: The huge amount of energy required for AI is raising questions about whether the industry's push toward ever-larger models is producing benefits that justify these growing resource demands.

What they're saying: In recent interviews, top sustainability executives at tech companies didn't directly answer if they would reconsider growth in the face of environmental concerns.

• "We are deeply committed to responsibly managing the environmental footprint of our operations," said Kate Brandt, Google's chief sustainability officer.
• "Our goal is not simply to slow the growth of environmental impacts," said Melanie Nakagawa, Microsoft's chief sustainability officer. Instead, the aim is "to reduce the intensity of each unit of growth over time, so that future growth really does become increasingly decoupled from that future impact."

State of play: Much of the AI industry has operated on the assumption that ever-greater scale is going to lead to better performance — and ultimately more profits, said Boris Gamazaychikov, who co-founded Sustainable AI Group, a research and advisory firm that helps companies address the environmental impacts of AI.

The other side: The potential for AI to improve people's lives and curb emissions is playing an increasingly large role in tech companies' sustainability messaging.

• Google devoted more of this year's sustainability report to AI's environmental benefits, highlighting uses from autonomous vehicles to scaling solar power.

Yes, but: Many of the AI applications companies highlight today rely on relatively narrow models rather than the frontier models driving much of today's data-center expansion, according to de Vries-Gao and Gamazaychikov.

• AI companies argue advances in frontier models eventually enable many downstream applications.

Zoom in: Gamazaychikov says AI models should disclose standardized energy-efficiency metrics, similar to fuel economy ratings for cars, so customers can compare how much computing different tasks require.

• "You don't need a Hummer to go to the grocery store," Gamazaychikov said.

Friction point: Environmental concerns may ultimately matter most through their economic consequences.

• Daron Acemoglu, an MIT economics professor and Nobel laureate, argues that if investment continues to outpace demand, the AI boom could eventually slow on economic grounds.

Flashback: Some of the world's greatest technological breakthroughs — canals, railroads, the internet — sparked enormous investment booms, with capital pouring into new infrastructure years before the economic payoff became clear, Axios' Courtenay Brown recently wrote.

• The AI boom appears even more extreme than those earlier investment waves, according to a recent analysis by an international group of central banks.

What we're watching: "The argument from the industry insiders is 'Just wait — the next two, three, four years are going to be different,'" Acemoglu said.

• The industry posits that this "technology is so exceptional, that it's going to buck all of these trends."

The bottom line: "I find that not completely convincing," Acemoglu said. "But it cannot be completely ruled out."