Solar Impulse, the first manned airplane to fly 24 hours on solar power alone, and to make a multi-national journey, has crossed the pond from its home in Switzerland to meet the press in the US before it prepares to fly across the U.S. in May. Co-pilots and project co-founders Bertrand Piccard and André Borschberg discussed the project and its goals at a press conference today (March 28) at Moffett Field in Mountain View, Calif. The team plans to circumnavigate the globe powered by nothing more than the sun. The U.S. will be a significant test-run for the project since it’s never flown this far at once before.
Solar Impulse has been making the impossible, possible for a number of years now. Like in July of 2010, it flew for 26 hours using only the power from its SunPower PV cells and the power they sent to its onboard battery. “For the first time in history an airplane has been able to fly day and night without any fuel—just on solar power,” said Piccard, Solar Impulse’s President. “During the day, the sun was loading the batteries and simultaneously running the electrical engines ... Showing that theoretically we can make a perpetual flight.”
During the event, SunPower CEO Tom Werner said, “They are shattering myths, just to fly around the world with no conventional fuels. Just destroying the conventional thinking.” He said their project is aligned with SunPower’s mission, which is to show that renewable energy can fuel the world. “We're going to prove that together. It's pretty fantastic and incredibly empowering.”
SunPower’s PV cells are the most efficient, commercially available silicon PV cells and have reached efficiencies over 24 percent. “It's also really thin, in fact…the thickness of the cell is just a few human hairs, so it's very thin, 135 microns. And because it's mass-produced it's inexpensive,” he said.
“The average power that we have during the flight, during the day, over 24 hours is the power of a motor-scooter,” said Borschberg, Solar Impulse’s CEO. “So we knew it had to be very big in size and if you know physics and aerodynamics, you can calculate how much this airplane has to weigh. That's the weight of a small car—3,500 pounds, including the pilots, including everything. This was the challenge.”
To meet the challenge the plane, particularly this version, is small and limited to one person, with a cockpit that would make most travelers yearn for a coach seat. And the trek won’t be nearly as fast as a jet, since Solar Impulse tops out at roughly 45 miles an hour. At that pace it will take days to make the trip and the plane will make stops with the pilots limited to 24-hour shifts at the helm. When they circumnavigate the globe, they’ll be piloting the plane’s sibling, which has a bigger cockpit and will allow for flights that last for days without touching down—after all, there’s no land across the Pacific Ocean.
“Our goal is to fly from Moffett to New York in five different legs,” Borschberg said. “The first will be Phoenix at Sky Harbor international. Then from there we go to Dallas, Ft. Worth International Airport. You can see all these cities want us to land on the main airports. Then we have the choice between three possibilities,” he explained. The candidates for that stop are Atlanta, Nashville, TN, or St. Louis. “All interesting for different reasons,” he commented. After that Solar Impulse will land in Washington, DC, and end its trek in New York at JFK Airport.
During the flight the team is hoping to inspire others. “Of course Solar Impulse is carrying one pilot and zero passengers, but it carries a lot of messages ... We'd like inspire students; school children. We want to inspire as many people as possible to try to have the same spirit to dare, to innovate, to invent,” Piccard said.
The team will transmit live from the airplane during flights so people can follow the mission, speak to the pilot and ask questions. Solar Impulse will also host events with some of the 80-plus partners that are participating, some of whom were on hand at the event. Among them Altran, Bayer MaterialScience, and Schindler. “This project belongs to all people who would like to invent a better future,” Piccard said.