Would you like that sunny-side up?!

April 7, 2010 7:32 PM

Solar takes to the skies. The Solar Impulse took flight today, reaching an altitude of 5500 feet over 87 minutes.With a wingspan of over 60 meters, close to that of a Boeing 747, it weighs about as much as a small car. Its 12,000 solar cells generate power for the 40hp engine, with an average speed of 70 kph (44 mph). The team will continue testing the prototype, including a 36 hour overnight flight, before constructing an even lighter, more powerful, more stable plane, with the goal of flying around the world in 2012, traveling both during both the day and at night, without fuel.
posted by markkraft (20 comments total)

It's weird to see a plane of that size move that slowly. Still, what a gorgeous machine.
posted by Think_Long at 7:44 PM on April 7, 2010

This carries a person, I assume? People have made solar powered drones in the past. Still pretty awesome.
posted by delmoi at 7:49 PM on April 7, 2010

On the surface, this sounds like fantastic stuff. Does it have real world implications?
posted by dustypinata at 7:49 PM on April 7, 2010

*nods* Yes, it carries a person.
posted by markkraft at 7:53 PM on April 7, 2010

Wow, the wings are only 264 pounds (120kg) and they support up to 5 tons.
posted by delmoi at 8:02 PM on April 7, 2010

It's not a solar powered airship, but definitely a step in the right direction.
posted by Caduceus at 8:05 PM on April 7, 2010

"On the surface, this sounds like fantastic stuff. Does it have real world implications?"

Only if you believe that pushing the limits in materials science to design planes, solar cells, and batteries more efficiently -- and then basically highlighting that innovation in an around-the-world demonstration -- could have all sorts of unforeseen influences on future designs.
posted by markkraft at 8:18 PM on April 7, 2010 [5 favorites]

Isn't solar-powered flight for the traveling public a physical impossibility given the low concentration of energy in solar radiation and the power requirements of moving relatively heavy people and their luggage?
posted by Dasein at 8:21 PM on April 7, 2010

Also, Solar Impulse chief executive André Borschberg has said that the pioneering work could also be put to commercial use.

"There could be direct commercial applications because there is interest for high-altitude flying platforms such as low-level satellites. We would be ready to share our technology if there is any interest."
posted by markkraft at 8:25 PM on April 7, 2010

Isn't solar-powered flight for the traveling public a physical impossibility given the low concentration of energy in solar radiation and the power requirements of moving relatively heavy people and their luggage?

Not if you charge $25 per carry-on and make Kevin Smith pay twice.
posted by bicyclefish at 8:26 PM on April 7, 2010 [2 favorites]

There are other green, fuelless airplane designs out there, btw. Here's a video demo for the Gravity Plane by Hunt Aviation, which is a kind of helium and compressed-air powered design.
posted by markkraft at 8:43 PM on April 7, 2010

dustypinata: “On the surface, this sounds like fantastic stuff. Does it have real world implications?”

I'm sure someone will be interested.
posted by Kadin2048 at 9:02 PM on April 7, 2010 [1 favorite]

Its 12,000 solar cells generate power for the 40hp engine

Time for some back of the napkin math. Let's take a 737-800. Worst case it's fitted with 19,500lbf engines and let's assume 80% cruising thrust maintaining a speed of 511mph (highly unlikely but deliberately conservative).

P(hp) = T(lbf) x V(f/s) / 550

P(hp) = .8 * 2 * 19500 x 750 / 550

P(hp) = 42,545hp

So we're out from a 737 by 3 orders of magnitude. Doesn't seem entirely practical.

Wouldn't it be better/easier to get the energy from a more easily harnessed renewable source, create fuel such as hydrogen or artificially created hydrocarbons and burn them instead?
posted by Talez at 9:44 PM on April 7, 2010

Hmm... interesting stuff, but I'm pretty sure that the Gravity Plane video claims they've not only invented a perpetual motion machine, but a terrorist proof perpetual motion machine.
posted by krakedhalo at 10:00 PM on April 7, 2010

around the world in 580 days?
posted by sexyrobot at 12:54 AM on April 8, 2010

"I'm pretty sure that the Gravity Plane video claims they've not only invented a perpetual motion machine, but a terrorist proof perpetual motion machine."

First off, there is no law of physics prohibiting perpetual motion, exactly; rather, the prohibition is against against any machine or system generating more energy than it consumes.

I'm not so sure, in that they generate a lot of their lift from helium, and their ballast is compressed air, which is heavier than the surrounding air pressure at that altitude.

Assuming that there is power enough to compress the air needed to offset the helium and start the plane's descent, and that the descent itself is able to turn turbines and compress more air, I don't see why this is unworkable. It's certainly going to be quite efficient, energywise. Hell... they could always add solar to the plane to help power things as well.
posted by markkraft at 4:38 AM on April 8, 2010

P(hp) = T(lbf) x V(f/s) / 550
P(hp) = .8 * 2 * 19500 x 750 / 550
P(hp) = 42,545hp

So we're out from a 737 by 3 orders of magnitude. Doesn't seem entirely practical.

Alternatively, perhaps a 737 isn't entirely reasonable. A high speed train could run at less than half that speed for a LOT less than half that thrust and would have more surface area into the bargain.
posted by DU at 5:05 AM on April 8, 2010

I love projects like this. Wish them all the best.

Here's a small, grouchy-sounding irony, though: How much client-side energy, in aggregate, is wasted by the inclusion of a bunch of pointless Flash animation on their home page?

Talez: So we're out from a 737 by 3 orders of magnitude.

So were the Wright brothers. I know, solar just isn't dense enough to ever make something like a 737 that runs directly on solar power, but this project probably isn't the end-point of this approach, either.
posted by Western Infidels at 9:26 AM on April 8, 2010 [1 favorite]

Didn't see this on the site: Roughly how much would the solar panels on this thing cost? Is this something that could feasibly be used to make remote areas less remote?
posted by PMdixon at 10:44 AM on April 8, 2010

"So we're out from a 737 by 3 orders of magnitude. Doesn't seem entirely practical."

Well it's only 1/2 - 2/3rd deficit on a lot of personal aircraft. Owning something like this would be all kinds of cool.
posted by Mitheral at 8:23 PM on April 8, 2010