If buildings that meet the rigorous qualifications of passive house construction seem impressive, or projects that attain the Living Building standard, such as the Bullitt Center , represent the cutting edge of sustainable design, a recently announced project in an Oslo suburb could be a game-changer, according to its developer. The Powerhouse Telemark, an 11-story office tower projected to open in Porsgrunn, Norway, promises to not just be sustainable, but to actually produce more power than it consumes.