Comments on: Solar-Powered Planes In Russia — Solar Being Considered As Replacement For Jet Fuel

By: Altair IV

Altair IV — Sat, 23 Feb 2013 14:55:00 +0000

From a similar previous story I gathered that while it takes a lot of energy to get an aircraft into the air, keeping it aloft takes relatively little. With a bit more work on energy density it may be possible to at least handle the middle stretches of a flight with solar/battery tech. And certainly renewable biofuels can replace fossil fuels during the take-off and landings.

By: Conrad Clement

Conrad Clement — Sat, 23 Feb 2013 14:12:00 +0000

Just how naive has one to be to believe Russia’s Ministry of Defense, who investigated the use of solar energy in light aircraft, to have stopped the project in 2010 due to “unsatisfactory results”?

For any Ministry of Defense (and especially the Pentagone) unsatisfactory results in this respect mean that they just found that there was huge potential for the civil society to challenge the absolute military control of the airspace — i.e., their joker for power enforcement from above — with myriads of personal ultra-light electric aircraft…

Moreover, Russia is living off its huge fossil fuel resources…

By: Conrad Clement

Conrad Clement — Sat, 23 Feb 2013 14:00:00 +0000

Hey, what about Mc Cready’s solar plane that took off from Paris Le Bourget, climbed to 9000 feet and landed five hours later on the other side of the Channel? (That was in 1983, I believe).

By: Zachary Shahan

Zachary Shahan — Fri, 22 Feb 2013 18:29:00 +0000

i realize that you wrote “commercial aircraft,” but you are aware of the Solar Impulse, right: http://cleantechnica.com/tag/solar-impulse/

that’s with today’s technology. technology in 30-50 years is going to be much better. “never say never.”

i know that Boeing & the US Dept of Defense have been working on a solar plane: http://cleantechnica.com/2010/10/04/boeing-solar-plane-solareagle-could-circle-earth-for-fiveyears/
+ NASA & Boeing: http://cleantechnica.com/2012/12/17/boeing-sugar-volt/

By: Ronald Brakels

Ronald Brakels — Fri, 22 Feb 2013 13:42:00 +0000

For use in space, solar panels have now gotten down to about a kilogram per kilowatt. At that weight it seems worth while to run a plane’s electrical systems off solar power when the sun’s shining to save fuel. It may not be a huge saving, but every little bit helps.

Hybrid electric small planes that receive some of their power from solar are also an option. Hybrid electric might seem an odd choice in such a weight critical application, but the added safety of having an electric engine powering the propellor may make it worthwhile. If the internal combustion generator fails, the plane can still land on battery power.

By: Bob_Wallace

Bob_Wallace — Thu, 21 Feb 2013 23:54:00 +0000

Robert, “never” is a dangerous word to use when making predictions.

There’s apparently no physical reason why we can’t learn to make batteries that store as much energy per pound as does liquid fuel. The theoretical energy density of lithium air batteries is about the same as gasoline.

We’re also looking at being able to reach the 50% efficiency point for solar cells. A plane design which presented a lot of horizontal surface (delta wing, for example) might make it possible for a commercial electric plane to harvest power and extend its range beyond battery range.

I’m not saying that we will get there, but I’m not willing to bet we won’t either….

By: shecky vegas

shecky vegas — Thu, 21 Feb 2013 23:54:00 +0000

Robert – With current tech, sure. But who knows what lies ahead?
And consider that jets get their lift from the thrust of their turbine engines. If you can generate the same amount of torque, what difference would the fuel source make?

By: shecky vegas

shecky vegas — Thu, 21 Feb 2013 23:49:00 +0000

Minpromtorg?

By: Robert M. Ryan

Robert M. Ryan — Thu, 21 Feb 2013 22:03:00 +0000

Great, but… I’m a huge fan of renewable technologies, I’m a pilot and aircraft owner, I’m directing my business toward deeper involvement with energy efficiency, generation and harvesting, transmission, distribution, and utilization.

But solar power will never directly power heavier than air commercial aircraft. Physics prevails. The power density of insolation is simply insufficient by orders of magnitude. Batteries will also, barring a breakthrough of unprecedented magnitude, not power commercial aircraft.

By: Otis11

Otis11 — Thu, 21 Feb 2013 04:26:00 +0000

So the question is – how much would we have to improve batteries to make them practical for current commercial aviation?

If that’s not feasible why not just turn toward hydrogen?