As artificial intelligence accelerates urban innovation, its environmental footprint is becoming impossible to ignore. In collaboration with The Economist Impact we explored the impact of AI on cities. While we help cities use AI responsibly, this article offers a big-picture look at the energy consumption of AI worldwide, which does not sit comfortably alongside cities facing energy and water shortages. The piece reframes AI not simply as a tool for efficiency, but as an energy-intensive system that must be governed with foresight and balance.