Solar Powered

This is a feature on tv tonight, but got me thinking about how the technology might be adaptable to other forms of transportation. Stuff like this is inspirational. It shows that science is certainly alive and well in the transportation industry. And it continues man’s quest to do what hasn’t been possible, and make it reality.

It certainly is revolutionary – the first solar powered airplane that can fly at night. Solar plans have been done before, but they were inherently limited. Taken from Solar Impulse’s site:

“Solar Aviation History

In the United States, Paul MacCready’s team developed the Gossamer Penguin, which opened up the way for the Solar Challenger. This aircraft, with a maximum power of 2.5 kW, succeeded in crossing the Channel in 1981 and in quick succession covered distances of several hundred kilometers with an endurance of several hours. In Europe, during this time, Günter Rochelt was making his first flights with the Solair 1 fitted with 2500 photovoltaic cells, generating up to 2.2kW.

In 1990, American Eric Raymond crossed the United States with Sunseeker in 21 stages and 121 flying hours over a period of almost two months. The longest leg was 400 kilometers. The Sunseeker was a solar motorglider with a glide angle of 30 and an empty weight of 89 kg, and was equipped with amorphous silicon solar cells.

In the middle of the 1990s, several airplanes were built to participate in the ‘Berblinger’ competition. The aim was to be able to climb to an altitude of 450m with the aid of batteries and to maintain horizontal flight with solar energy power of at least 500W/m2 , corresponding to about half of the power emitted by the sun at midday on the equator.

The prize was won in 1996 by Professeur Voit-Nitschmann’s team from Stuttgart University, with Icaré II (25 meters wingspan with 26 m² of solar cells.)

Even if it could not carry a pilot, one must not forget Helios, developed by the American company AeroVironment for NASA. This remote-controlled aircraft, with a wingspan of more than 70 meters, established a record altitude of nearly 30 000 meters in 2001. It was destroyed during flight two years later as a result of turbulence, and crashed into the Pacific Ocean

In 2005, Alan Cocconi, founder of AC Propulsion, succeeded in flying an unmanned airplane (drone) with a 5-metre wingspan for 48 hours non-stop, propelled entirely by solar energy. This was the first time a device of this type was able to fly through a whole night, thanks to the energy collected by, and stored in, the solar batteries mounted on the plane.

From 9 to 23 July 2010, the Anglo-US company QuinetiQ made a non-stop flight of 336 hours, 22 minutes (14 days) with its drone Zephyr (27 kg, wingspan 12m), at an altitude of 21,562 m.

With its huge wingspan equal to that of an Airbus A340, and its proportionally tiny weight – that of an average car – the HB-SIA prototype presents physical and aerodynamic features never seen before. These place it in a yet unexplored flight envelope.

Carbon fiber structure, propulsion chain, flight instrumentation, everything has been designed to save energy, to resist the hostile conditions facing airplane and pilot at high altitudes and to marry weight restraints with the required strength.

It was not built to fly round the world. Its purpose was rather to demonstrate the feasibility of the program by making the first ever whole day-and-night flight without fuel, a task that it accomplished brilliantly in July 2010. The lessons learned by the team are now being applied to the construction of Solar Impulse HB-SIB, which is due to circumnavigate the Earth in 2015.

The first test flight across North America, at night, is slated for next year

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