The heat is on for two Texas college rivals facing off in Washington, D.C.

The Department of Energy's Solar Decathlon has the University of Texas and Texas A&M students transforming the national mall into a solar village.

The two schools are part of twenty worldwide teams chosen to design and build solar powered houses.

The homes have to be entirely powered by the sun, and Wednesday they got started.

"People think about the classic showdown between the Aggies and the Longhorns at Thanksgiving. Well, this is the real classic showdown between their building engineers," said Andy Karsner, Department of Energy. "Texas is a special environment where the City of Austin is the greenest city in the nation by volume of purchases of green power and has a very active green building program. That's obviously contagious when you go a couple of hundred miles down Highway 6, and so the battle is on for who has the best engineering department in Texas."

It took two years for each college to design, test and build their homes.

This Friday they'll be finished, open to the public and up for sale.