Ready for another exciting competition in the world of prefab solar houses? The 2010 Solar Decathlon Europe has kicked off in Madrid, Spain, marking the first time the competition has been hosted in Europe! Seventeen teams from around the globe are battling it out in the center of the city to see who has the most efficient solar powered and eco-friendly house. Just like the competition in Washington DC, the teams will be graded on their ability to minimize their energy use, innovative architecture and engineering, sustainability, and more. Read on for our exclusive photos and a first look at the most exciting houses in this year's competition!