Data centres have lots of computers that get very hot while they run. Usually, that heat is just wasted by cooling it down with fans. In London, people found a smart way to fix this by using that extra heat to warm up water for nearby houses. This is a great solution because it uses energy that was going to be thrown away instead of burning fuel to make new heat. It helps families stay warm and is much better for the planet because it saves energy and stops unnecessary pollution.
