Twenty college and university teams from around the world competed in the recent Solar Decathlon that is held every two years in Washington, D.C. The U.S. Energy Department sponsors the event, and this year's winner was Technische Universität Darmstadt. VOA'S Paul Sisco has more.

Solar home part of the Solar Decthalon on the mall in Washington, DC

The mall in Washington, D.C. looked something like a solar village. Students from across the United States, Canada, Spain, Puerto Rico and elsewhere are here showing off their solar homes.

"You're supposed to show the house is livable. So that's one of the things we focused on, is that people feel they can live there, so we get points for that," explains Jacob Cigna, from the University of Maryland, which placed second. "There are 10 contests. That's why they call it a decathlon. One of them is architecture. One of them is engineering. Is it market viability, communications, energy balance - a lot of different categories."

Inside the home built by the Maryland team

The Maryland team calls its entry "the LEAF House." 

"LEAF House stands for Leading Everyone to an Abundant Future," explains Nirmal Mehta, "and we believe that the leaf is nature's best solar collector, and we try to emulate that not only in our engineering but in our architectural design.

"We've got this ridge with knife blade system that kind of looks like the stem and veins of a leaf, plus this super skylight lets light through just like a leaf with our solar panels on top," adds Mehta.

Each of the 20 entries is unique. Some are more elaborate than others. Many incorporate extensive landscaping into the design. All are powered solely by the sun.

Thousands of Washington visitors attend the event. The homes are on display for nine days. Then as quickly as they went up, they are taken down. They are returned to their respective schools, some for student housing, some as research laboratories, others as exhibits highlighting the creative excellence of their student builders.

The ultimate goal of the Solar Decathlon is to build enthusiasm for environmentally friendly home construction, and to spark ideas and innovations in the next generation of architects and engineers.