"New Jersey's first entry in the biennial national Solar Decathlon in Washington, D.C., is easy to tell from the rest: It's the only building made of concrete.

"The 960-square-foot, one-bedroom house dubbed Enjoy weighs more than 500,000 pounds, with the unique "inverted hip" shaped roof tipping the scale at 150,000 pounds alone."

http://www.northjersey.com/news/national/130489038_N_J__students_turning_heads_with_solar_house.html