Blog Post Wednesday 09 July 2014
For as long as I can remember solar cars have hogged the limelight when it comes to solar powered vehicles. But really, when you think about it, flicking some solar panels on the wings of the plane just makes so much more sense.
I mean, the plane’s going up toward the sun anyway, it might as well catch some rays while it’s up there, right?
Solar powered planes have actually been taking tentative take offs since way back in 1979. Since then solar airplanes have been steadily developing to be able to fly higher for longer.
The big hurdle with using solar panels to power any kind of vehicle is that the amount of power generated is limited to the size of the vehicle.
Planes might seem like a good option because they have all that wingspan to panel up, but once you start adding any kind of weight to the plane, you start needing more power to deal with the weight and more panels to provide that power.
One way to get around the power issue is to include more battery power into the mix. The more batteries for the solar panels to charge, the further it can go. However, more batteries add more weight, requiring, you guessed it: more power. It’s an aeronautical catch 22.
And while there are continuous developments in the effectiveness and efficiency of solar PV panels, the weight issue has been kept solar flights from flying significant distances since the first take off.
But a pair of Swiss engineers are taking great strides in changing all that. In 2015 pioneering aviators Bertrand Piccard and André Borschberg plan to circumnavigate the globe in their solar-power plane, the Solar Impulse 2.
They have already broken the long distance record for a solar flight with their previous plane, the Solar Impulse, and just this past June, they successfully completed the very first test flight for the Solar Impulse 2.
To solve the energy issue, the Solar Impulse 2 had to be both light and powerful.
By using a composite of carbon fibre and flexible yet rigid ‘honeycomb sandwich’ panels, the team were able to keep the plane’s final weight to that of a small van. Without a drop of fuel, the plane is solely powered by the 17,000 solar cells spread across its impressive wingspan – equal to that of a Boeing 747 – giving it’s four electric motors the grunt it needs. And finally, to fly through the night, the Solar Impulse 2 is fitted with rechargeable lithium batteries. Charged by the panels through the daytime, they provide the grunt needed to get through to the next break of day.
If everything goes according to plan it will be the first round the world solar flight. One that Piccard and Borschberg hope will be a massive step toward solar being a viable option in powering commercial planes.