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Fuel Cell Powered Japanese Trains on Trial in July
ScorpFromHell writes "As per this yahoo! news item, "East Japan Railway Co. is to conduct a test run of the world's first fuel-cell-powered train in July.
The fuel cells, which generate power from a chemical reaction between hydrogen and oxygen, will help reduce environmental pollution compared to the existing electric and diesel engines, the company said."
But I wonder how much energy did it consume to produce those huge amounts of Hydrogen & Oxygen? Will it be lesser than the power generated by the reaction between them?
In other words, can this technology be used by countries with not so deep pockets as Japan?"
Wikipedia calls it an "Electrochemcial" reaction. Which sounds a little more reasonable to me, though I suppose it can still be referred to as a plain "chemical" reaction. It just doesn't seem very precise.
http://en.wikipedia.org/wiki/Fuel_Cell
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" I wonder how much energy did it consume to produce those huge amounts of Hydrogen & Oxygen? Will it be lesser than the power generated by the reaction between them? " But of course! Now you take the energy generated and then produce more Hydrogen and Oxygen, then put it back in the cells and generate yet even more energy. The world's energy problems are solved at last! And who would have thought -- by a Japanese train and an observant Slashdotter.
Seriously, what can be possibly better than electric trains? Unless your electricity comes from coal, in which case replacing the power station to something else, say nuclear, would make more sense.
.. sheesh!
Fuel cells are useful for energy storage. Perfect to, say, drive a car for a few hours, then dump some more into your energy storage, and drive back, in any direction. Also, they're good to bring energy to remote location. Setup a quick electricity generator in the middle of nowhere. But for trains? They go on tracks, so installing a few wires isn't too expensive or difficult, making the electricity transportation far more efficient trought wires than fitting fuel cells on every locomotive, and then carrying all that hydrogen and
Really, i see this as the wrong match of a technology to a need.
Combustion is a chemical reaction.
The way a fuel cell works is the same as burning straight Hydrogen. 4 Hydrogen atoms combine with 2 Oxygen atoms to form 2 Water molecules. When you burn Hydrogen, it happens all at once in one big pop (or bang!). In a fuel cell, the atoms dissolve into the water at the electrodes and combine in solution. The reaction is much more controled and generates an electric potential at the electrodes.
As far as efficiency is concerned, the seperation of Hydrogen and Oxygen (by electrolosis) from water and the subsequent recombination in a fuel cell (creating electrical energy) is over 95% efficient. That compares to around 30% for a good diesel engine.
In high school, I actully built a rudementary fuel cell as a science project.
Summarized this is a test vehicle being used on a non-electrified line in a mountainous region. The advantages are less local pollution (which can be a significant issue in mountainous regions where diesel exhaust can linger or even concentrate in valleys) and no large capitol investment in line electrification & maintenance. A side benefit is the advantages of an electrical train without power lines intruding into the landscape.
As a regular user of urban commuter rail service this sounds like an interesting development. The cost of electrifying a rail line is prohibitive yet the all-electric engines are quieter and less polluting, a big sell in expanding service in urban & ex-urban areas. Technology like this could certainly quiet the complaints of many neighbors as well as improve the air quality near central stations.
I don't read ACs: If a post isn't worth so much as a nom de plume to its author then I wont bother either.
Fuel cells are an energy storage medium, not an energy source.
You are half right. Fuel cells are neither an energy storage medium nor an energy source. The source of the electricity used to hydrolyze the water is the energy source. Hydrogen is the energy storage medium The fuel cell is an energy conversion device same as an internal combustion engine except way more efficient.
You need to look into how that hydrogen is being produced. The only large scale production of hydrogen that I know of makes hydrogen from natural gas, a fossil fuel. And it is amazingly wasteful and inefficent, and as dirty as burning natural gas or gasoline in a motor veichle. Although it does allow one to relocate the polution from a given area, it contributes even more to global warming than older technologies.
I'm an American. I love this country and the freedoms that we used to have.
I think by "diesel and electric" they mean "diesel-electric". Basically, a diesel engine (usually with separate cylinders which can be independently replaced) drives an electric generator, or bank thereof. This in turn is used to provide power to electric motors which provide motive force for the train. The benefit is that by doing this you eliminate the need for a drivetrain, gearbox, and so on. Thus, the total weight is not changed much, but you get peak starting torque (electric motors make peak torque at 0 rpm) and you aren't constantly replacing gearboxes, drivelines, clutches, et cetera, as you would be if you were trying to put all that power through a conventional drive system. Of course, it's not exceptionally efficient. At best, the generator might be 90% efficient, and so might the drive motors, and the most efficient internal combustion engine in the world is a diesel the size of a house in a container ship that's only 50% efficient... the engines in trains are probably pretty efficient (another benefit is being able to run the engine in its powerband most of the time, except when it's running at low power and maybe at max load) but they're not even 50%.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Wow...pop? dissolve?
"As far as efficiency is concerned, the seperation of Hydrogen and Oxygen (by electrolysis) from water and the subsequent recombination in a fuel cell (creating electrical energy) is over 95% efficient."
Whoa! Sure that's the efficiency of electrolysis but then you have to compress and store the hydrogen (hydrogen storage is a whole thing in itself), then you have to feed it to a fuel cell that has an efficiency much less than 95%...usually less than 50% system efficiency. Overall, the total efficiency of hydrogen fuel cells is comparable to a diesel fueled vehicle, maybe even a bit less.
Of course, that's if you make the hydrogen by electrolysis. Most hydrogen comes from natural gas at the moment, which is less efficient and produces CO2.
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Except that at least in the case of Japan, they have a lot of neukular power plants. It could be that they siphon the hydrogen and LOX off of the liquid gas extraction plants next to a couple of steel mills that are relatively close to the rail yard.
Much like biodiesel from recycled french fry oil doesn't scale, this method may not scale either, but it's good to actually have one to see how it pans out in real-world service.
It's no different really than Union Pacific's experiments with gas turbine locomotives, or US and European experiments with steam turbine locos, closed-cycle steam locos, etc.
I think more interesting will be how GE Locomotive's hybrid diesel-electrics work out. If the battery pack had enough amp-hours to replace one locomotive from the consist as a large train tries to power up a mountain grade, then perhaps it'll really justify itself. Of course, it won't work out on lines with multiple grades right after another (Appalachians?), but up places like Cajon Pass it might be beneficial.
Is the efficiency of a power plant really so much better than your car?
Yes, from a thermodynamic perspective it is, as well as economy of scale-wise. The coal plant is running at a steady state, and the average car engine does not. The Otto cycle engine's advantage is its flexible power output curve, which is needed for cars, especially in urban driving. Supplant a smaller displacement Otto-cycle engine that meets the power needs of the car to cruise at 70mph on the flats with an electric assist motor (instant full torque) and battery pack, and you kind of get the best of both worlds without trying to make the gas engine too complicated (i.e., variable displacement, etc).
What, rich people should do things that are economically stupid?
It's not about this being stupidly inefficient, yet Japan can afford to do it anyway because they're rich. The question is, which is a more efficient use of electricity (or, more generally,. resources), running an electric train, or running a hydrogen/oxygen fuel cell train? Whether you're rich or poor, you should still use the technology that works best for you.
I think it might have occurred to someone in Japan to check and see if this is better than running a conventional electric train in otherwise similar conditions before building it. Although it's quite possible they didn't care. It could be like ethanol in the US, which is used for political reasons, not because it's an efficient way to improve the environment. Depending on who's counting, it generates between .7 and 1.5 times as much power as it consumes to make. We could reduce pollution (including carbon emissions) much more by spending the money we spend on ethanol on nuclear power, solar arrays, or wind power. Ethanol fuel, in it's present state, is government graft to benefit corn farmers and ease the conscience of environmentalists who don't understand it.
I am interested to know if this train really is about a great new technology for saving the environment, or a political ambition.
Can anyone tell me how to set my sig on Slashdot?
Nuclear wants to be the one true energy monoculture - which is stupid when most of the installed plants are 1950's style economic white elephants and the newer designs like pebble bed lose the thermal energy economy of scale by having small safer units. It's a pity that the nuclear debate ranges between bare faced lies (too cheap to meter) and utter horror with little in between and so few agencies giving out real information. Find a real research reactor (clue - reasearch reactors in places like Indonesia, Pakistan, India, Israel, Nth Korea etc have a military bias) and listen to stuff that comes out of those places - they keep coming up with solutions to major problems that snake-oil salesmen trying to sell nuclear power pretend don't exist in the first place. A reasonable solution for waste storage has been worked out for a tiny fraction of the amount that was spent on advertising that nuclear power is "clean" and the stupid premise that if ash heaps at coal fired plants have traces of radioactivity then it's OK for nuclear power to spread radioactive waste about instead of constructively dealing with the problem.
Fuel Cell Powered Japanese Trains on Trial in July
What are they on trial for?
Huh? Ohhhhhh....
my pet machine
A pure Fuel cells system is in the order of 70-80% Combined with an average 80% motor, you have 50-60% efficiency.
OTH, if use a reformer rather than a regular storage system, you lose the bulk of the efficiency (lowers you to 30-40%). Combine that with the 80% motor, and you are in the 24-32% efficiency.
Sadly, an autmobile is around 20% efficiency. And that is only from the Gas forward. It does not include the previous inefficiencies.
Basically, we are using one of the worse systems possible. It just got developed and marketed first.
I prefer the "u" in honour as it seems to be missing these days.