Some new studies show that they sell faster for LA Times">higher prices:
"In a study covering existing and new houses sold from May 2010 through April of this year, the Earth Advantage Institute, a nonprofit group based in Portland, Ore., found that newly constructed homes with third-party certifications for sustainability and energy efficiency sold for 8% more on average than noncertified homes in the six-county Portland metropolitan area. Existing houses with certifications sold for 30% more."
Source: LA Times