Photo: Tekla S. Perry

Inside, however, the Y2E2 building is filled with innovations that save energy and water and make life inside more pleasant. This atrium, one of four in the building, brings daylight all the way down to the basement, which saves on electricity for lighting. The atrium is not air-conditioned, acting instead as a chimney for natural cooling. The louvers at the top open automatically on summer nights, letting cold air in.