London Underground will harness waste heat to warm homes

The systems that power air conditioning, industrial factories, and the train for your morning commute generate vast amounts of heat and energy—and most of it goes to waste.

But London has new plans for the heat generated by its rapid public transit system, the London Underground. The city just announced that it would begin harnessing waste heat from its Northern line to warm up offices, community centers, and homes in the borough of Islington.