STEVE INSKEEP, HOST:
An aircraft is making its way around the Earth powered by the sun. The Solar Impulse 2 will soon make the most hazardous leg of its journey, flying across the Pacific Ocean from China to Hawaii. That journey is expected to take five straight days and nights. And for that entire time, one pilot will be sitting at the controls. His name is Andre Borschberg, and he's on the line from China. Welcome to the program, sir.
ANDRE BORSCHBERG: Thank you very much. Good morning.
INSKEEP: I've been looking on the Internet at photographs of your plane. I guess it looks almost like a - like a glider with exceedingly long wings. What distinguishes it?
BORSCHBERG: It's the size of a 747 with the weight of a gas or something extremely light, but also very big. What makes it special is that you can fly one week, even one month nonstop with the energy of the sun. It is extremely energy-efficient.
INSKEEP: The top of the wings, those are solar panels - is that right?
BORSCHBERG: The top of the wings, the fuselage, yes, they are all covered with the solar cells, I think 17,200, which collect the energy during the day. We store it in two different ways - the latitude as we climb to 20,000 feet and of course, also in batteries. Both are used to fly through the night, first by descending at lower speed over the ocean and then using the batteries until sunrise.
INSKEEP: Oh, now that's fascinating. One of those things I would have guessed - that you have batteries on board for when the sun is not shining. But you're saying the other thing that you do to store energy is simply climb high, and then you can gradually descend and fly for a very long time that way. Is that right?
BORSCHBERG: Yeah, that's right, for about three or four hours. And then we have about eight, 10 hours from the batteries are sufficient. We fly through the night and continued the following day. Now we are in China ready to cross the ocean. And hopefully, we demonstrate the possible of this technology - not so much for our nation, but more to promote the potential of these clean technologies that we have on board.
INSKEEP: Compared to a normal airplane, what does it feel like to be at the controls of the Solar Impulse 2?
BORSCHBERG: Well, it's absolutely marvelous. So I fly and I produce energy. Then I have the choice - if I land in the middle of the night, I can give this energy to the grid, or I can continue flying through the night. And of course, the major question is we have only one pilot on board - if we can make the pilot sustainable as well.
INSKEEP: OK, that pilot is you. How do you plan to stay awake for five days and nights?
BORSCHBERG: Well, first of all, doing short resting period of 20 minutes using some kind of an autopilot. Then we'll also use other techniques. I train yoga since 20 years. I do meditation. And I will use these first to stimulate and keep the body functioning, but also the mind with the right mindset, the right attitude.
INSKEEP: How long has a journey like this been on your mind?
BORSCHBERG: We started 12 years ago. My partner flew around the world with a balloon in 1999. This was the first time the balloon could circumnavigate the globe. And at the time, in fact, they used quite little propane, and we had really started to think about the possibility of getting rid of this dependence on the fossil energy and have something functioning only with renewable energy.
INSKEEP: So in a minute, were you feeling a little competitive then? You can fly around the world in a balloon; I can do it in a solar plane.
BORSCHBERG: That is - of course, that is the part of evolution. You know, the world is made of people who try new ideas and that's how we go forward. That's also the kind of inspiration we like to give to the young generation - believe in your dreams, try. You may fail at the beginning. But because of failures, you will learn and that's when come for success.
INSKEEP: Andre Borschberg, good luck to you.
BORSCHBERG: Thank you very much.
(SOUNDBITE OF MUSIC)
INSKEEP: He is attempting the first solar-powered flight around the world. You're listening to MORNING EDITION from NPR News. I'm Steve Inskeep.
DAVID GREENE, HOST:
And I'm David Greene. Transcript provided by NPR, Copyright NPR.