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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?"
Fuel cells are an energy storage medium, not an energy source.
Centralizing power generation should be more efficient than millions of smaller generators all over the place.
Now, it's just a matter of finding out if generating, transporting, and storing the required hydrogen is environmentally/economically better than diesel or gasoline.
"In other words, can this technology be used by countries with not so deep pockets as Japan?"
I think a better question would be "Why isn't the U.S. doing more to be in the forefront of promoting alternative fuel sources?
Steve,
http://tail-f.net/
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
Javascript + Nintendo DSi = DSiCade
" 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.
I think that the GP poster meant to ask: Will the manufacturing process for these batteries produce less CO2 than the maximum usage of the trains with fossil fuels?
In any case, I think it's worth it. We've researched fossil fuels too much. It's time to research about alternative energy sources.
First of all, combustion is a chemical reaction.
Second, your use of the phrase "power plant" implies using combustion to generate heat, which is then used to expand a gas to drive a piston to move a linkage etc. This is called a fuel cell instead because it uses the reaction between hydrogen and oxygen to produce electricity which then drives an electric motor and so forth.
In other words, H2 + O2 -> H2O can be used to drive combustion engines and fuel cells.
"[Regarding the 'cloud,'] ownership was what made America different than Russia." -- Woz
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.
I don't think you should expect to be modded down for asking a reasonable and well thought-out question. Isn't that the whole point of having a discussion?
You are so boring that when I see you my feet go to sleep.
hold on a sec.... Electric train engines produce pollution? How is that possible?
Granted, a fair amount of power is lost in the transmission lines, but given that they're run at such a high voltage to begin with, that shouldn't be a huge issue (P=I^2*R). Is more power lost in the transmission process than the process necessary to manufacture and produce all this hydrogen and oxygen?
Fuel Cells are nifty as an energy storage medium, but for trains, they seem wholly inappropriate, especially when electric trains eliminate the need for a storage medium at all (and in a country as densly populated as Japan, this shouldn't be an issue at all)
-- If you try to fail and succeed, which have you done? - Uli's moose
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.
Alright, everyone's going to jump down the guy's throat for:
/.er out there with some nice statistics for us all.
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?
However, I think we should question the efficiency of this. If it takes X amount of energy to run a normal train, but 4X to produce the fuel cell, then is that really a good thing? It's like people saying that electric cars are so much better for the environment. Instead of burning gasoline, you burn coal (or whatever) in the power plants. Is the efficiency of a power plant really so much better than your car?
I don't know the answer to that, but I'm sure there's a
Wer mit Ungeheuern kämpft, mag zusehn, dass er nicht dabei zum Ungeheuer wird. --Nietzsche
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.
Well, sir, there's nothing on earth ...
Like a genuine,
Bona fide,
Electrified,
Six-car
Monorail!
Proof by very large bribes. QED.
I gotta call BS on this 95% number; where are you getting it, because it is way off from the numbers I have seen.
--
WHO ATE MY BREAKFAST PANTS?
Having spent a lot of time analyzing the hydrogen economy in terms of generation, this topic is near and dear to my heart.
Hydrogen is a method of TRANSPORTING and STORING energy. It is not a solution to energy generation. As a storage and transport method, IMSO (S=Scientific), it is not particularly cost effective, and has as much potential for unforseen concequenses as any other untested energy method.
That said, I am highly in favor of fuel cells in general, and am happy to see them adopted more often.
In relation to the question asked about poorer countries, I would also hasten to point out that the fuel cells themselves are expensive, as they require (I believe) a platinum catalyst.
That is all.
hmmmm?
In other words, H2 + O2 -> H2O can be used to drive combustion engines and fuel cells.
Except that fuel cells don't combust per se. Which was my point. The hydrogen acts as the Anode, the Oxygen as the Cathode, and the plates between them strip off the hydrogen electrons to create a voltaic imbalance. The actual combustion of the two is secondary to the energy generation, and is not directly used by the process. The only thing used is the attraction between the hydrogen and oxygen atoms.
A combustion engine on the other hand, uses the pressure developed by the combustion to produce mechanical energy which can then be translated into electrical power through the use of a dynamo or generator.
The point I'm getting at is that the article feels incredibly imprecise. There is an electrochemical reaction occurring that produces power output, but the actual chemical reaction is not harnessed. Or at least, that's the one way of looking at it. You do still end up with a recombination of the electrons, protons, and oxygen to produce water in the end so I guess I can't entirely fault the article.
Javascript + Nintendo DSi = DSiCade
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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The efficiency of electrolysis is very high, 95% is actually possible. BUT, electrolysis has nothing to do with generating power, electrolysis is how you separate water into H2 and O2. A fuel cell is actually less than 50% efficient, and the overall efficiency of hydrogen fuel cells is comparable or a little less than diesel fueled cars.
"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?"
First law of thermodynamics says . . . NO!
And as Homer Simpson put it, "In this house we obey the laws of thermodynamics!"
But that's largely irrellevant if the energy to produce them was derived from an energy source that is not exausted by use, such as solar, hydro, or geothermal sources.
File under 'M' for 'Manic ranting'
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.
Wikipedia calls it an "Electrochemcial" reaction.
I hope you took the time to fix the mistake!
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?
Even if it takes about the same energy to produce the chemicals, this is ok. Don't think of a fuel cell as an energy producer, it's an energy storage device. This is like a battery. When you charge a battery, you don't get a net increase in energy. You are merely moving electricity that is produced in an electric plant into the battery. The train is the same idea. With something the same size as a train, I can't see any reason not to just use a battery. In fact, you could potentially have a batery car or something like that to store the energy and it would be cheaper than fuel cells. Fuel cells are mainly interesting in automobile applications because their energy storage density is greater than Lithium batteries. Still it's good to see work being done on the fuel cell front.
No Sigs!
My understanding is that it's possible for ethanol production from corn stocks to be energy-positive but it takes expensive equipment. However, it's pretty well-known that there are other stocks from which ethanol can be generated that are more easily energy-positive. You're quite right about the fact that ethanol production from corn stocks in the US is currently just another farm subsidy, though.
Of course, if you're really going to be doing biofuel, you're better off doing biodiesel, which is definitely energy-positive, and which has significantly higher energy density than either ethanol or veggie oil - just thought I'd throw the veg in there to cover all the bases.
However, in any case, topsoil-based fuels are the completely wrong way to go. If we're going to do biofuel, we need to be growing the fuel stocks hydroponically. All farming leads to the depletion of topsoil one way or another, whether it's blowing away because it's not covered by the native grasses that protected it and let it get to where it was, or because of depletion due to a lack of rotation which I can see being a huge potential problem if you're growing crops so you can turn them into fuel. Topsoil is less than 40% mineral... Hell, IIRC, it's significantly less.
In my opinion, if you can't get the power from substantially low-impact sources like wind, solar, or tidal, then it should be nuclear, and breeder reactors should be used, because depending on who you believe, they reduce waste (or improve efficiency, however you want to look at it) by something between two and three orders of magnitude. Then the real issue is how to store and transfer that power. Hydrogen is a reasonable way to accomplish that, especially using fuel cells, provided you can keep the energy consumption and pollution down in the manufacturing process.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
CH4 + O2 + Energy --> CH3 + H02 (Chain initiation)
(I'll skip the rest of heavy organic chemistry lecture. The short form is here but be ready to consult an organic chemistry and and a combustion theory book for the nitty gritty details.)
From there you have a series of other chemical reactions where energy is released as the compounds break down into CO2 and H20 (Carbon Dioxide and Water).
The amount of energy released is fixed by the amount of methane burned. (I am assuming an idealized stoichiometric reaction with no left overs or pollutants) The method of capturing and using the energy released is what is important.
If you burn the fuel you get: heat and pressure. From there you can use it to generate steam power, electrical power, etc etc etc. The current efficiencies on gasoline engines (in your car) is running around 30%. Most of the waste energy goes out the tail pipe or the radiator. If you are planning on producing electrical energy or driving a vehicle from the power of the engine, you also have to start considering drive train losses.
In a fuel cell: energy is provided to strip chemical bonds that hold methane together, then hydrogen is seperated and then allowed to recombine with the oxygen to make water, the carbon forms carbon dioxide. The second two reactions produce energy. The trick to the fuel cell is that less of the energy is wasted in lost heat, pressure, etc. Efficiencies in fuel cells easily run over forty percent, are quieter and have less drive train losses. The electrical power drives the motor directly with no transmission or gear losses.
Architectural plans are like computer source code with a couple of differences: You only compile once.
"Much of Japan's fabulous rail system is electrified, but for those routes still running diesel-electric locomotives the NE-train is coming. The diesel generator is replaced with two 65 Kw Hydrogen powered fuel cells and a hydrogen tank to power the motors and it stores regenerative braking energy in batteries."
From here.
I've done a tour of a pumped-storage power plant in North wales. Dinorwig (sp?) from memory. Anyway, it used cheap, off peak electricity to pump a metric buttload of water up to a reservoir on top of the mountain, and then generate power during the daytime and sell it back to the grid at peak rates. Big advantage was that you could go from 0 output to ** MW within a minute or two. Pretty amazing place, huge man made gallery inside the hill. http://en.wikipedia.org/wiki/Dinorwig_power_statio n
The problems with any hydrogen/oxygen storage mediums are: 1) Even liquid hydrogen has low densities 2) The potential for a devastating explosion with a hydrogen leak is a serious danger. And since hydrogen is colorless and odorless, one may not detect the leak until it's too late.
difference with the greenhouse gas water vapor is that there's a quick removal cycle for water (days to months) compared to carbon dioxide and methane (takes centuries to process by being absorbed by ocean). So once water gets back to liquid form the cycle is complete. So you'll essentially be increasing local rain near cities rather than driving a long term accumulation like we're doing now.