As the first day of competition week of Solar Decathlon Europe begins, there is a rush of decathletes and organizers on the already sunny grounds below the Royal Palace to get the houses ready to compete and to prepare for visitors. Busy city workers help lay out the last patches of mulch and gravel to shape the team lots. Students perform very Solar Decathon-typical chores as they mop off dust from PV panels and start positioning themselves to receive the crowds.

The real measure of success is: If you build it, will they come? This is the first time a Solar Decathlon is being held in Madrid, so one never really knows if the people will like it until the doors open to public visits on the first day. At 11 a.m., people were waiting to get into the village, and it wasn’t long before lines of people were waiting to get inside the houses. It is very gratifying to see the public interest. I assume, because today is Friday, we will see larger crowds this weekend. Congratulations to everyone involved. The hard work and dedication has produced a successful event!

Prince Felipe de Borbon, son of King Juan Carlos of Spain, visited the Solar Decathlon Europe village today at 6 p.m. He personally greeted each team and toured four houses.

Prince Felipe lifted the spirits of all the teams with his sincere interest and congratulatory well wishes and words of encouragement. During his visit, he shook the hand of every student and faculty member and wished them well. After a photo with many decathletes, he said goodbye about 7 p.m.

As the sun rose brightly over the Villa Solar, I could feel the excitement building among the decathletes—for in just a few hours, the first Solar Decathlon Europe would have its historic opening. After last-minute cleaning up, decathletes emerged from their houses dressed in team uniforms and lined up in front of the stage.

As dusk fell Wednesday evening on the Solar Decathlon Europe Villa Solar, Stuttgart University of Applied Sciences became the first team to finish building its house and have it ready for visitors. The University of Applied Sciences Rosenheim followed closely behind. Both German teams were jubilant and glad to finally have time to rest and appreciate their accomplishments.

Richard King is the director of the U.S. Department of Energy Solar Decathlon. Throughout the Solar Decathlon Europe competition, U.S. Department of Energy Solar Decathlon organizers are reporting from Madrid.

The final stretch. Today is the last day for assembly at Solar Decathlon Europe. All houses must be completed, inspected, and connected to the power grid by this evening, or they cannot score points on the first day of competition. Some teams, such as Virginia Tech and Stuttgart University of Applied Sciences, are finished, but others, including the the University of Florida and the Instituto de Arquitectura Avanzada de Cataluña, still have a lot of work to do. I had dinner with a couple of the Florida team members last night, and they were upbeat about their prospects. As soon as Florida finishes its decking—hopefully today—it will be ready.

The pace has really picked up today at Solar Decathlon Europe. Teams are working double-time because only 35 hours of construction time remain. The opening ceremony will begin Thursday morning at 11 a.m. to officially open the Villa Solar.

The best part of the Solar Decathlon Europe assembly period is the continual surprises as the designs are revealed. Some of the new things I saw today were:

• The Universidad de Sevilla’s (Spain) solar chimney with ceramic tubes for natural cooling
• Stuttgart University’s (Germany) exquisite multicolored photovoltaic side walls
• The Ecole National Superieure d’Architecture de Grenoble’s (France) stucco walls, which were hand-applied by one of the best tradesmen in Japan
• The Universidad CEU Cardenal Herrera’s (Spain) parabolic solar collectors, which heat transfer fluid to cook food in the oven.

The Instituto de Arquitectura Avanzada de Cataluña house is capturing a lot of excitement at Solar Decathlon Europe. Now, all of the large sections of the house have been assembled and placed.

According to the team’s faculty advisor, Vincente Guallart, the team found a Spanish company to make flexible PV modules using 22%-efficient SunPower cells. On Saturday, a vice president of SunPower visited the team to check on progress. The vice president was excited and intrigued that someone could make a flexible module using the rigid cells. There are 21 cells in series for each module. The flexible material could have been clear, but the team chose black.

Byron Stafford is the site operations manager of the U.S. Department of Energy Solar Decathlon. Throughout the Solar Decathlon Europe competition, U.S. Department of Energy Solar Decathlon organizers are reporting from Madrid.

Solar Decathlon Europe is spectacular, wonderful, amazing, and awesome. The teams of students and faculty are just wonderful to talk to, and the homes they are building are even more brilliant than anything we have seen at past events.  Maybe it's the fifth generation, maybe it's the Spanish rules, or maybe it's the international diversity, but Solar Decathlon Europe is sure to be historic in terms of showcasing what the state of the art is around the world.  I am trying to put into words what my jet-lagged brain is trying to say, and hopefully more will become clear as the event progresses, but to bring together the best thinking from around the world must be significant. We are all looking for solutions, and to bring all these ideas together in a competitive melting pot so we can all learn from each other—you just have to believe progress is being accelerated.