Helsinki Blasted Out an Underground Lake To Water-Cool Its Buildings

If you've visited Helsinki, you've probably spent time in its leafy Esplanade Park at the center of the city. Now Helsinki has turned the ground below the park into a subterranean lake which can keep buildings and other civic operations cool as part of a growing network that replaces traditional air conditioning… » 9/08/14 1:34pm 9/08/14 1:34pm