<http://schema.org/about>
"The Powerhouse concept of energy-positive buildings takes materials and construction into account, as well as operations. This is really important and difficult to do. "^^<http://www.w3.org/2001/XMLSchema#string>
<http://www.treehugger.com/green-architecture/powerhouse-kjorbo-worlds-most-environmentally-friendly-office-building.html>