The blog recently showed an Alpaero Exelec electric motorglider to which Francis Marlier of the ultralight club of Alsace, France, had taped 66 square feet of solar cells. The Sunexelec that resulted has enhanced endurance, managing up to four-hour flights, although Francis does not indicate how much of that is soaring flight and how much powered. He reports, “Using SUNPOWER C65 solar cells which are encapsulated in modules of 20 or 15 cells. The total weight per wing of these modules is about 3 kilograms (6.6 pounds). “I have used special 3M adhesive tape to fix the modules [which are 0.8 millimeters (3/64-inch) thick] directly on the wing skin. Special covers are put on the wings that I remove just before the take-off. During the flight there is no risk to damage the epoxy resin.” His airplane has a 60 Volt, 30 Amp-hour battery pack measuring 30 x 30 x 20 centimeters (11-13/16 x 11-13/16 x 7-7/8 inches) to power …
Hydrogen Scooters – A Possible Power Source?
Amateur aircraft builders, like Francis Marlier of the ULM Club in Alsace, France who recently converted his Exelec to a Sunexelec with the addition of solar cells, are always looking for reasonable options for powering their airplanes. Perhaps they could turn to fuel cells as a range extender. Several motor scooter makers are bringing out fuel-cell powered models that show some promise despite limited performance and high prices so far. Intelligent Energy, an English company, demonstrated a fuel cell scooter in 2005, and a number of aircraft developers, including Boeing, have crafted fuel-cell-powered vehicles. Intelligent Energy’s ENV was reportedly the world’s first purpose-built fuel cell motorbike, and Top Gear’s James May enjoyed the quiet ride, if only moderately endorsing the bike’s sedate performance. http://www.youtube.com/watch?v=igrKemNvxZQ Intelligent Energy’s entry for the Make It in Great Britain exhibit at the Science Museum gives a brief overview of proton exchange membrane fuel cell technology. “This award winning zero emission electric vehicle is powered by Intelligent …
Sunexelec – Recharging in Flight
The Club d’Ultra Léger d’Alsace is a group of French enthusiasts in Strasbourg, on the German border about halfway between Luxembourg and Switzerland. They have been building ultralight aircraft since 1983, tackling technological innovations such as carbon fiber leading edges, motorization, electrification, and now solar power. They were the first to motorize a Swift, and with one of their craft electrically powered, mounted strips of photovoltaic cells to the upper wing surface. Finding that worked to boost battery duration, the group went on to mount 6.1 square meters of solar cells on an Alpaero Exelec, an ultralight self-launching sailplane. After making 60 flights on battery power between May and April of this year, the group installed the solar cells on the wings, flying 18 times on solar assist between May 21 and July 20. These included eight launches in which the solar cells recharged the airplane’s LiFePO4 batteries during the flight, making the possibility of endless cross-country flight a realizable …