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.

Comments

Which Fuel?

[squaretorus]

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?

Re:Which Fuel?

[znu]

You're ignoring the "where they want to go" part of your own statement. Smaller planes flying to smaller airports will put people closer to their final destinations. Direct flights everywhere will save people the frustration involved in layovers. Less reliance on major hubs will relieve congestion and delays. All things considered, in most cases you'd probably have much shorter total travel times (including time to get to/from airport and to get through the airport onto the plane and into the air), and a major reduction in the sort of circumstances that bring on "air rage".

Building a Hydrogren Fuel Cell? Semi-OT

[redcliffe]

I'm about to begin constructing an electric car, and instead of using batteries which are heavy and expensive, I've been thinking about building a hydrogen fuel cell. Anyone know of some good web pages about that? Thanks,

David

The airline industry wanted this for years

[Billly Gates]

This is definitely good news. Not for the technology or environment per say but for political stability in the middle east and terrorism. Ibet none of you have any idea of how much power the oil indistry has to suppress such research for years on in.

The oil industry has such an effect in this country that its totally unbelievable (USA, for Europeans who hate American centered comments :-))! Basically they lobbied the FAA to make sure that fuel cell technologies for planes would never be approved. Boeing who is afraid of developing an engine that the energy-industry sponsored FAA would not allow them to sell, decided to only research fuel cell technology but not build any prototypes for obvious reasons.

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.

Explosions & the environment

[Master Of Ninja]

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. If it's just a safe (and maybe quieter) I wouldn't mind having it at as a power source - i mean it doesn't actually power the engines themselves so we should be quite safe.

It's good to see that they are changing over to some environmentally friendly stuff. Most people have this stereotypical view that US companies are not very "green" - this might set them straight (although it's interesting that they've based the work in Europe...) Testing the fuel cell on cars would be a good idea as well - someone's probably already done this, but if hydrogen can be cheaply produced (cheaper than oil that is - nobody's going to change over to a new fuel source unless it is cheap) it should be an excellent fuel (practically no pollution).

Tandential benefits.

[karlm]

The biggest problem with fuel cells in airplanes should be the weight and bulk of the entire system. This is especially true for small aircraft. However, fuel cells provide many befets, especially compared to the piston engines used in sport aircraft.

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.

Re:Hydrogen dangerous?

[DarenN]

I would like to point out that that fuek used is _liquid_ hydrogen, not gaseous like the hindenburg.

It is extremely difficult to hangle due to the fact that it is stored at waaaaaaay below 0C. IIRC it isn't particularly flammable as it vapourises. Plus, the tanks it's stored in are pretty robust.

Re:Risks involved

[Gordonjcp]

Well, one (imperial) gallon - 4.5 litres - of petrol, in vapour form, has roughly the explosive power of 1kg of dynamite. So, consider the explosive power of the average fully-fueled car. My Citroen XM has a 17-gallon (roughly 80l) fuel tank. Big boom.

The explosion risk is actually slightly higher for unleaded petrol (technically they're all unleaded in the UK now, but in this case I mean 95RON lead-free) than for 98RON Lead-free Four Star. This is because instead of nice, safe, but *slightly* poisonous Tetraethyl Lead, lead-free uses Benzine, which is much more volatile, extremely poisonous and highly carcinogenic.

Diesel fuel doesn't really explode well at all. Jet fuel (basically very clean paraffin, like heating oil) is somewhere in between.

Environment Friendly Flying

[dhart]

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!

congrats Boeing, you're SECOND

[mr.ska]

A fuel cell-powered airplane is being worked on. Admittedly, it's not an airliner, but it's still the same problems, just on a smaller scale.

EVWorld.com has the two-part story and interview with the plane's builder here (1) and here (2).

Different types of Fuel Cells

[ArhcAngel]

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

Modern fuel cells use alcohol to produce hydrogen

[SysKoll]

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. :-)

--SysKoll