The latest rage is the possibility of an all electric plane, because of the Solar Impulse making a 18 hour trip from San Francisco to Phoenix Arizona at an average rate of around 40.6 mph, it only had 1 person(the pilot). The full specs. Crew: 1 Length: 21.85 m (71.7 ft) http://en.wikipedia.org/wiki/Wingspan: 63.4 m (208 ft) Height: 6.40 m (21.0 ft) Wing area: 11,628 photovoltaic cells rated at 45 kW peak: 200 m[SUP]2[/SUP] (2,200 sq ft) Loaded weight: 1,600 kg (3,500 lb) http://en.wikipedia.org/wiki/Maximum_takeoff_weight: 2,000 kg (4,400 lb) http://en.wikipedia.org/wiki/Aircraft_engine: 4 × electric motors, powered by 4 x 21 kWh lithium-ion batteries (450 kg), providing 7.5 kW (10 HP) each Take-off speed: 35 kilometres per hour (22 mph) Just the total weight of people on a average commercial plane is around 14 or so times heavier then the entire max takeoff weight of the Solar Impulse and probably another 4x for all the luggage. And for any decent travel the speed is 12.5 to 13 times as fast as the Solar Impulse. Besides just for recreational personal use, are solar powered planes a waste of effort? I saw one person mention on yahoo comments that if you take university level physics and engineering you will see its impossible for practical solar powered plane and everyone neg repped him on there. Was he correct or just not willing to see the future?