Swiss adventurer Bertrand Piccard unveiled a prototype of a solar-powered airplane with the wingspan of a commercial airliner but the weight of a small family car. He plans to fly it around the globe to demonstrate the potential of renewable energy.
Piccard plans to start with a 2012 test flight across the Atlantic Ocean. The Environmental Transport Association pointed out the difficulty Piccard will face in conserving enough energy during the day to fly at night.
Solar as a power source for an aircraft is not new. It has been successfully used before as the sole power source and as one part of a hybrid power source. http://en.wikipedia.org/
He would need to gain plenty of height during the day so that at night he would mainly be gliding but then he would need to carry oxygen which would add weight.
Solar with a fuel cell to provide power at night. Used in combination with surfing thermals during the day and gliding at night might do the trick, but I don't hold out much hope in this case.
