Solar Impulse will fly only on solar power
The environmental cost of air travel is atrocious. What if a free source of power were found that could power a plane with out damaging the environment? One such effort is being developed by Bertrand Piccard. Piccard is working on the Solar Impulse.
In 1999, Bertrand Piccard flew the Orbiter 3 balloon around the world. Now he has set his sights on making the same journey in the Solar Impulse plane. The Solar Impulse as envisioned, will be able to use solar power alone to take off and fly both day and night for several days. The wingspan for the initial prototype will be 60 meters (65.6167 yd) and the wingspan for the final plane will be 80 metes (87.4890 yd) there will be considerable room for solar cells.
Since only about 8 hours of sunlight is truly useful per day. This means that the solar cells used to power the plane by day must also charge batteries that will fly the plane by night requiring very efficient solar cells. The plane will have “12,000 photovoltaic cells in 130 micron monocrystalline silicon, selected for its capacity to combine lightness and efficiency.” The batteries have to be able to power the plane for the remaining 16 hours, requiring extremely light and efficient batteries. So far the right battery combining light weight and efficiency has not been found.
The Solar Impulse project has been broken down in stages to allow for adequate testing and technological advancement. The initial planning stages began in 2003. 2007 and 2008 should see the production of a prototype(s) for testing and the first overnight flights. Then larger prototypes will be introduced in 2009-2010 for longer test flights. The final stage should occur in 2010, when the flight around the world is expected to finally be possible.
Viable solar flight will cut down on the amount of air and noise pollution generated by airplane travel. Although this technology may not be commercially available for several years, the flight of the Solar Impulse could be as significant as Lindbergh’s historic flight in promoting the new technology.
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June 2nd, 2008
Has anyone considered ultra/super capacitors for energy storage? I am not sure about weight considerations, but they have some big bonuses over traditional batteries. Just a thought…