Monday, August 24, 2015

Swiss researchers tested solar-powered aircraft

An experimental solar-powered aircraft Solar Impulse 2 has large fixed wing covered from tip to tip with 17,000 photovoltaic cells providing 340kW of electric power. The aircraft is powered by taking off in the daylight and rising to an altitude of 9,000m as the sun charges its batteries.
At night, the engine is switched off and the plane glides down to 1000m, and then the plane needs to find cloudless sky to charge its battery in the morning so as to fly continuously. Professor of Aeronautical Engineering, Professor Chris Atkin, says that "the limited potential for solar-powered aircraft is instructive. Solar energy density is something like 0.25 kW per square metre, assuming that these solar cells are one hundred percent energy efficient. An Airbus A330 aircraft burns 60 kW per square metre of wing area, i.e. 240 times more than would be available from perfectly efficient solar energy capture”. Read more at