The world relies on manufacturing, and manufacturing relies on heat — a massive contributor to global carbon emissions, responsible for a quarter of the world’s fossil fuel use. Energy entrepreneur John O’Donnell has figured out a better, cleaner way to generate the heat we need to make the stuff we want. Learn how his team turned simple bricks and iron wire into a powerful, unconventional “heat battery” that could deliver industrial heat at scale without the emissions — and why he thinks electrified industrial heat is the next trillion-dollar industry.