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Boeing to Develop a Fuel Cell Powered Airplane
gilgsn writes: "From Yahoo News: Boeing is working with a light airplane manufacturer in Spain on a fuel cell powered plane. The efficiency of electric motors, with their reliability, acceleration, lack of vibrations and noise has a lot to offer to general aviation. The project aims at exploring environmentally friendly modes of propulsion. I can easily imagine a hybrid aircraft using fuel cell technology for take-off and altitude gain, coupled with solar cells to sustain flight. I hope a kitplane manufacturer in the United States will read this. I can't wait to fly a fuel cell powered ultralight!" CD: The question is can a fuel cell deliver enough energy for a flight long enough to be practical.
He recently witnessed a demonstration of a hydrogen-fueled automotive fuel cell that was so environmentally friendly its only byproduct was water safe enough to drink.
So they are talking about a H-O fuel cell. Agreed, but what about the risks of explosion? Seriously, I'd done some fuel cell research a couple of years back and one of the biggest problems the people doing it faced was regulating the flow of hydrogen & oxygen. More often than not, the flow would go awry. Ofcourse I'm not talking about small scale ones, I'm talking of large ones, developed for seeing how well fuel cells could be used in industrial areas. I'm sure these would be the kind of ones which would be used in such things as planes, too.
And given something like a plane, we cannot afford to have such uncertainities and risks.
With Fuel Cells you boil down to a trade off between the efficiency and cost of the fuel.
Plain old hydrocarbons are cheapish, easy to handle, and not overly dangerous in a 'leak' situation.
But they require hyper advanced self cleaning fuel cells that wear out quickly.
Pure methanol is expensive (purification always costs), easy to handle, and not overly dangerous in a leak situation.
It works in cheaper, more reliable, longer lasting and lighter fuel cells.
Hydrogen is expensive, difficult to handle, and pretty damn dangerous stuff in ANY situation.
It works best with fuel cells, pretty much optimal.
A fuel cell that can handle ANY carbon rich material, and takes O2 from the atmosphere would be the holy grail. You could use argicultural by products to produce methonal, dig up oil, LPG, any burnable liquid essentially.
A rethink on the air network strategy to produce lighter, smaller, more efficient aircraft which possibly fly a bit slower and take shorter 'hops' would bring Fuel Cell flight closer.
This would be a worthwhile trade off for a more environmentally sound and sustainable flight infrastructure.
Boeing and Airbus both seem committed to increasing the size of aircraft overall. Maybe its time for a serious rethink?
Eletric plane? what about a power drop? it needs a UPS i tell you :)
"What do you mean you have no ice? Do you expect me to drink this coffee hot?" - Random Customer, Clerks
Is hydrogen that dangerous? In a leak situation it quickly disperses and floats away right? As opposed to other fuels that will burn in an accident. I mean everyone dies in plan crashes anyways, I donlt think the survival record can get much worse. And if we all had secure hydrogen fuel tanks in a safe location in our cars and then I proposed that we instead carry around many gallons of flamable and explosive gasoline in thin tanks that rupture in accidents followed by the fuel spilling and flowing until it found a spark you would all call me crazy.
-Steven
The oil industry has such an effect in this country that its totally unbelievable (USA, for Europeans who hate American centered comments
However the September 11 attacks changed this. I was within 2 or 3 blocks from the World Trade Center and it was not the plane attacks that brought the buildings down but over an hour of intense 2000F heat that melted the support beams. As much as 2 Olympic sized swimming pools of jet fuel went inside the 2 buildings. 200,000 gallons in total. I am amazed that the towers even stood for that long. I assume most of the 4,000 people who perished would of survived if it wasn't for the deadly fire and jet fuel. Many didn't make it out in time or the heat was so intense that the stairways actually melted where the fire was.
Another problem we have is politics in the middle east. Americans have historically been strict isolationists. I would like it to stay that way. This all changed during both world wars and also during the rise of the oil industry. The 1991 gulf war was not about the suffering of those poor Kuwaiti's but for Exxon's, enrons, as well as Mobile's stock prices and profits. Bush senior received large amounts of money from the oil industry and we went to war to defend there interests and their cash. This is what started this whole Afghanistan mess we are in now. This is why China and the Arab world views Americans as empirialists. We represent more of the British empire in early America more then our original government. Our taxes now are actually much higher then before the American revolution! Believe or not. No wonder they view us as self serving empirialists. We actually are. Saudi Arabia is oppressive and the latest posts here on slashdot which state there intent to block internet access confirms this. We have no reason to support them other then for our energy interests. The sooner we lossen the oil industries grip the better. Also the Israeli's are being persecuted by terrorists groups funded by Arab's. I am aware the same can be said of the Palestinian persecution but when one group attacks another they both point fingers at each other and become more militant and oppresive. Before the 1950's the Arabs were all poor and lived in third world conditions. They ignored Israel before they had the money to fund Hummus. Thank oil for changing this. Anyway greed is bad and I am glad the government now is realizing that our dependence on foreign oil is bad. I believe fuel cell technology is the wave of the future for not only planes but cars as well.
http://saveie6.com/
The article mentions that fuel cells are twice as efficient as heat engines. I thought the efficiency gap was larger. In any case, the laws of thermodynamics place an upper limit on the efficiency of a heat engine (such as a turbine or piston engine). This upper limit is known asw the Carnot efficiency. It is determined by the ambient temperature and the temperature of combustion. 30% is a decent estimate of the Carnot efficiency for a gasoline engine with the ambient temperature about room temperature. I thought fuel cells were about 80% efficient, but then again I'm on a coding break at 5 a.m.
The MGM brushless DC motor developed at NTU in Australia has an efficiency around 99%.
The main advantages of fuel cells for sport aviation are the extremely high efficiencies and the good reliability of the components. Electrical components and non-moving mechanical components have much higher reliability/cost ratio than their moving counterparts. I've held aircraft pistons with valves imbedded in them. Some people much prefer the Wankel rotary engine in aircraft for its simplicity. Turbines are much better in terms of reliability, but their cost is much higher. One should also consider maintenance costs. An aircraft piston engine typically needs to completely overhauled every 20,000 hours of operation to ensure reliability. Fuel cell inspection and overhaul involves many fewer parts and is probably much cheaper and probably needs to be done less frequently. The same should be true for electric motors.
Another important factor in using electric motors is that the propellers can be designed more optimally if they don't have to deal with the large accelerations and decelerations that a 6-cylinder piston engine produces 3 times per revolution. Piston engines (even with flywheels) are very rough running, and propellers are beefed up so that they don't tear or shake appart under these loads. Any time you have to beef something up, you end up increasing the cost, weight, and/or innefiencies.
Let's not forget that most sport aircraft require 110 octane "low lead" fuel that is expensive and releases polluting lead compounds into the environment.
Copyright Violation:"theft, piracy"::Anti-Trust Violation:"thermonuclear price terrorism"<-Overly dramatic language.
ecosoul sells a fuel cell kit, and there are instructions (pdf) from homepower mag about how to construct one.
"Where shall the word be found, where will the word resound? Not here, there is not enough silence." -T.S. Eliot
Hi,
... that is if a field is in range. Electric engines should increase reliability quite a lot. Hopefully they are available soon.
There are already several electrically powered aircraft flying. Ok, most of them are gliders that use the engine for take off and then retract it and continue flying, gliding and gaining altitude in thermals. But there is already a powered glider, the icare, which uses solarcells to power an electric motor for take off and sustained cruise.
Take a look at the following websites:
Lange Flugzeugbau
Icare
Silent AE1
Conventional self launching gliders are already very sophisticated, but the engines they use, require a lot of maintenance and are sometimes not as reliable as you might wish. Well anyway, if the engine fails I land on a field, no problem there,
Regards, Thomas.
What about the risk of explosion in a fuel cell? Hydrogen is very volatile - you need a really good system that prevents tampering, leakage, electrical activity outside the plane, and can withstand crashes. I'm thinking about the Hindenburg airship disaster here when making comparison at the moment. I'm not an expert on these things so I would really like to know how the gas used in the auxiliary unit would "burn" in comparison to hydrogen in the event of a disaster.
Flammable fuels are only explosive when it has mixed with air in a sufficient quantity to form a fuel-air mixture. This is different from volatility, which is a measure of how easily a compound turns into gaseous form (petrol/gasoline, for example, is quite volatile, as is ethanol). The fact is that Hydrogen is the lightest element on the periodic table and hence diffuses through leaks and openings much more quickly than, say volatile fumes from regular petrol or JP9 jet fuel (where the fumes consist of multiple gaseous hydrocarbons, which have greater molecular weights and are hence much heavier). This is why there is no gaseous Hydrogen in the Earth's atmosphere. The Hydrogen simply floats away into space.
If you were to be involved in an accident involving an aircraft equipped with a Hydrogen fuel cell, you'd find that the chief cause will not have been the Hydrogen. The combustion of the fuel used in the aircraft's engines (remembering that the Hydrogen fuel cell will be used as a backup device to generate air and power for the aircraft and not as a means of propulsion) would have caused the lion's share of the damage. The only noticeable effect the Hydrogen would have on the acccident is to perhaps allow the fire to burn a little longer (assuming that enough of the Hydrogen is still contained in the air and has not diffused into the atmosphere). When being used in fuel cells, Hydrogen chiefly stored as a compressed, possibly liquefied gas. Hydrogen can also be stored in certain metallic compounds (known as metallic hydrides, which hold the Hydrogen atoms in a similar way to amalgum containing Mercury) to increase energy densities. In the first case, the rapid diffusion of the Hydrogen gas would not cause a fire for the reasons outlined above. In the second case, the Hydrogen would not be released because it is still bound to the metallic hydrides. In either case, it is unlikely that the cause of the accident will be the Hydrogen fuel. Hydrogen has, in fact, been proven to be a safer fuel to handle than gasoline. The byproduct of the fuel cell is water vapour, so it's also much better for the environment.
Your comparison to the Hindenburg disaster is not really applicable in this case, as it was conclusively demonstrated that it was the Aluminium compounds in the paint on the Hindenburg that caused it to burst into flames and not the Hydrogen gas. The Hydrogen ignited later, burning much more slowly and for a lot longer and hence actually acted as a fuel that sustained the fire, as opposed to the agent that caused the ship to burst into flames in the first place (remembering that the ship still burned even though the outer material had been completely destroyed).
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When the pin is pulled, Mr. Grenade is no longer our friend.
This is Fantastic!
I fly regularly between Australia and the US. I would gladly extend the duration of the already long trip (14 hours) for the trade offs:
o Environmentally Friendly (by a large degree)
o Quieter
With longer fight times and lower fuel carrying requirements, hopefully these new planes would become more passenger friendly as well (no more deep vein thrombosis). If there's a bar and a free Internet connection, I have no problem spending 24 hours on a plane!
Fuel cells and electric motors will not replace jet engines on commercial transports, but they could one day replace gas turbine auxiliary power units. Auxiliary power units, which typically are located in the rear fuselage with exhaust ports through the tail, are coupled to generators and compressors to produce electricity and air for airplane systems while on the ground and for backup use in flight.
Let me repeat, they are NOT trying to use fuel cells to replace the jet engines. They are going to use them to replace auxilary power units, which simply produce electricity.
So basically, this entire discussion here on /. is about the wrong thing! Not only is it about the wrong thing, but the thing that has been announced isn't that big of a deal. These are not electric aircraft that they are producing!
So move along now, the really is nothing to see here.
Lasers Controlled Games!
EVWorld.com has the two-part story and interview with the plane's builder here (1) and here (2).
Mr. Ska
I've always thought that aircraft wings are one of the most obvious places to put solar cells. On a day-time flight, you're practically garuanteed maximum sunshine for the whole duration.
Even if you don't use it directly to power the engines, there's still plenty of electronics on your average aircraft that could use it.
(Spudley Strikes Again!)
Many of the posts alude to the potential of a hindenburg type explosion on a plane that used such a fuel cell system because of the Hydrogen involved. According to the article Boeing is looking at using fuel cells but it doesn't specifically mention hydrogen fuel cells except to say one was seen used in an automotive demonstration. There are many different types of fuel cells http://www.fuelcells.org/fctypes.htm each having it's pros and cons. I do see a move to "alternative" types of fuel but, as always, economics will drive the shift as much as anything else. Right now energy companies are scrambling to figure out how to profit long term on systems that are so efficient. Anyone old enough to remember when an automobile wouldn't go over 75,000-100,000 miles without a MAJOR overhaul? It wasn't because they couldn't be more reliable but becaue the big 3 made $$$ off of the repair parts as well as new car sales. If the Japanese companies hadn't offered more efficient/reliable products in the 70's we might still be seeing the trend.
OK, I think I sufficiently wandered off topic
"A person is smart. People are dumb, panicky dangerous animals and you know it." - K
As others have suggested, if I could just invent a fuel cell that dealt handily with carbon- and nitrogen-rich fuels, I could help the environment and get rich.
The question is can a fuel cell deliver enough energy for a flight long enough to be practical.
The answer is, "yes".
Fuel cells are very efficient at converting chemical to electrical energy -- the cells NASA has been using on manned spacecraft since the 1960s run at about 75% efficient -- compare that to the roughly 30% efficiency of a combustion engine. (Although for a proper comparison we'd also need to factor in the efficiency of the electric motor. At 85%-90% (numbers I've seen quoted) that gives a net chemical-to-mechanical efficency of about 64%-67%.)
As far as safety goes -- well, NASA has been running H2-O2 fuel cells on manned spacecraft since Gemini, and the only problem they've ever had with that system was due to a combination of spec changes and improper procedures causing an O2 tank to explode (Apollo XIII).
-- Alastair
Everyone here is assuming that the fuel cell based auxiliary generator discussed in the article will be using hydrogen.
Actually, a lot of work is being done on fuel cells burning alcohol (ethanol). Either you use a cracking step to produce hydrogen on-the-fly by decomposing the alcohol molecule with a catalytic grid, or you use a pretty fancy membrane to rip the hydrogen directly from the alcohol molecule.
Either way, you don't need to carry a hydrogen tank. So save the Hindenburg references for a more appropriate topic.
Since alcohol is actually less energetic per kilogram than kerosen, I don't see why it would be dangerous. The only problem is that it's one more fluid to carry in airports, and that would probably require even more work and red tape than getting an alcohol-burning fuel cell approved by the FAA.
The residue of such a fuel cell is alcohol remains mixed with water and various catalytic by-products. In other terms, watered-down alcohol with metalic salt traces and a few moderately toxic molecules. Not very dangerous either. Heck, with a bit of luck, airlines will decide to tap this residue and sell it to passengers in lieue of the horrible Californian el cheapo wine they serve with meals. :-)
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