It was the last day of the Solar Decathlon, so I made my way to DC to investigate the houses thoroughly. I was impressed by what I saw: the houses were all designed to be portable, solar-powered and eco-effective. Attention was paid not only to energy production, but also to rainwater collection, green roofing and space-saving design features like Murphy beds. It was good to see all of these ideas embodied in real prototypes. The back of this house by the University of Maryland, had a roof which held its solar panels in an elegant curve. You can also see the solar hot water tubes attached to the side of the house, which fed into a radiant flooring system inside. More details can be found on their web site.