Heat underground

District heating infrastructure has been around since the 19th century and is already built under many cities around the world. The idea is to have a cogeneration facility that generates both heat and power near an energy load in a city, campus, or region. Power is generated and fed to the grid, while the heat--in the form of steam--is fed into the underground network. France-based Veolia Energy owns and operates a number of district heating systems in the U.S. serving commercial customers, such as hospitals, universities, and high-rise buildings.