Artificial intelligence is easily the most deceptive technological innovation of the 21st century. Its ease of use and the lightning-fast reflexes with which it spits out responses belie its enormous appetite for water and energy.ChatGPT took the world by storm when it launched in late 2023, signalling an era of intelligence demand marked by seamless, conversational interactions between user and machine But behind every smooth exchange lies a complex physical process. Modern AI is built on vast neural networks trained on trillions of words, images, and numbers. This training, to help models learn to predict the next word or recognise a pattern, involves processing colossal datasets repeatedly through graphics processing units, or GPUs. These chips, originally designed for rendering video game graphics, have become AI workhorses because they can perform thousands of mathematical operations simultaneously. But this speed comes at a price: intense heat.