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Do Hydrogen fuel cells make sense? — Parallax Forums

Do Hydrogen fuel cells make sense?

lardomlardom Posts: 1,659
edited 2010-06-08 21:49 in General Discussion
I have wanted to research hydrogen fuel cells for over a year now. I thought it would make sense to use solar cells to produce hydrogen. It's on the back burner because I am still working on my second project. (I found 4 errors on my first custom PCB and ordered a corrected version.) I'd like to·know if any of you think·solar hydrogen·is a waste of time.
· This by the way is one of the notions I've had about finding ways to get off the electric grid. I've also pondered 12V or 24V household utilities. Anyway, I'd like to hear some thoughts.

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Comments

  • Mike GreenMike Green Posts: 23,101
    edited 2010-06-05 16:52
    There are major energy losses every step along the way. You've got the low conversion efficiency of solar cells. Then you have the energy losses in electrolysis to produce the hydrogen. Then you have the problem of storing the hydrogen and losses there. Then there are the losses in the fuel cells.

    In terms of relatively mature (and affordable) technology, the best way is to combine solar panels with a large battery bank and inverters to produce 120VAC or 240VAC. Include solar hot water panels for household hot water and design or improve your residence for highest efficiency in terms of passive solar heating and cooling. Depending on the climate, you can also do a lot of cooking using solar energy.

    I think long term the successes will come in harnessing the photosynthesis reactions to produce electricity. In areas with lots of sunlight (like Northern Africa), thermal solar power looks like it could work well if they can transport the energy to where it's needed.

    Post Edited (Mike Green) : 6/5/2010 4:58:34 PM GMT
  • John R.John R. Posts: 1,376
    edited 2010-06-05 19:48
    The potential problem with low voltage household utilities is voltage drop. Power = Volts X Amps. Assuming similar power requirements for a given task, If your voltage is only 1/10th (12V vs 120V) then your current needs to be 10X. This increases the voltage drop for any given length of wire. In addition, while a volt or two is relatively insignificant on a 120 volt circuit, on a 12 volt circuit, every volt counts.

    There is probably more bang for the buck (and time) in looking at more efficient appliances and lighting systems. Here (lighting systems) is one area where low voltage may work out (LED Lighting).

    As far as a hydrogen fuel cell, if you're getting the electricity from a solar cell to start with, it probably makes more sense to store it (the collected energy) in batteries than in hydrogen. As Mike pointed out, every conversion carries cost and losses. You want electricity, and the most efficient way we have to store it right now is chemically (batteries).

    Hydrogen fuel cells may have applications, but I see them more in terms of things like cars, etc., where there is some advantage to using hydrogen as a storage medium. (joules per cubic inch or per pound)

    Don't think in terms of fuel. Think in terms of energy storage. Fuel is something "harvested" (or mined, drilled, etc.). Solar power is energy, and we need to transform and store it as efficiently as possible. While hydrogen can make a good fuel, it is (at least currently) not a very good storage medium.

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    John R.
    Click here to see my Nomad Build Log
  • bill190bill190 Posts: 769
    edited 2010-06-05 22:17
    I read a bit about fuel cells several years ago and research was being done on this, but I see the auto makers have decided to go with electric vehicles without fuel cells, so I guess that·is the answer to that!

    And that is the only use I saw for fuel cells - automotive.

    So far as solar for a home, you get the most bang for the buck with a solar water heating system. Then of course control it with a Basic Stamp or Propeller. Hot water heating can be 30% of an electric bill.

    Then do everything you can to reduce parasitic loads. These are electronic gizmos which are "always on".·Following is a link·to an interesting paper on this...

    Leaking Electricity: Individual Field Measurement of Consumer Electronics
    Lawrence Berkeley National Laboratory...

    http://enduse.lbl.gov/info/ACEEE-Leaking.pdf

    Then replacing old appliances with new Energy Efficient models can be quite a savings. Newer A/C, furnaces, refrigerators, freezers, and front loading washing machines can save quite a bit. Things which heat with electricity do not save anything with newer models. Like range, space heater, baseboard heater, etc. Electric heat is electric heat. However a new heat pump can save energy.·All sorts of energy saving·tips·at energystar.gov

    Once you have reduced your electric load with solar water heating and so forth, solar electric become more affordable although it is still quite expensive. For this you can use the electric grid as a "battery" by using a "grid-tie inverter". This gizmo produces grid synchronized electricity and sends the excess generated electricity out onto the electric company's wires/grid. Your electric meter would run backwards or they would install a special meter to measure how much electricity you are "selling" to the electric company.

    At night time, you use electricity from the grid. Thus batteries are not needed with this setup.

    This is called "net metering" and what you get paid and how much you will be reimbursed by the electric company is determined by state laws which vary. Anyway search for the term net metering and look up your state's laws on this. Also this can be different for a specific electric utility, so also check with your electric company as to their rules.

    And all of this *must* be approved equipment and installed to National Electric Code rules and inspected. Electricity works backwards. A homeowners solar system could energize the electric wires during a power outage, go backwards through the transformer, and energize the high voltage wires as well! (Then possibly electrocute a utility worker or someone coming in contact with a down line.) Thus these are designed to shut down outgoing power in the event of a power outage (for safety).

    ·
  • mctriviamctrivia Posts: 3,772
    edited 2010-06-06 01:26
    i think fuel cells are a great thing for mobile devices like cars and laptops but useless for your house unless you are buying the hydrogen from someone else and using as a backup generator.

    Mike has the right idea on the best way to go for your house. Now if you have extra solar power go ahead and use it to make hydrogen and power your car off that. lift truck and gulf cart bateries are about the cheapest power storage method you can reasonably use for your house.

    as for 12V vs 120V the 12V may be more efficient since you don't lose in the inverter which can be a large drop even if drawing no power. But that gain is lost by the cost of cabling needed in the house.

    To comply with Canadian Elctrical Coda there can be no more then a 3% drop on the cables.

    This means at 120V you are allowed a max of 3.6V and at 12V only 0.36V

    For a 1440W load(max continuous load allowed on a 15A breaker) you can go 15.2m(50') on 14AWG wire. At 12V for the same 1440W and 15.2m you would need 400MCM cable. That is a huge very expensive cable which is normally only used for industrial panel feeders.

    Lets try the math a 120W(estimated load of each receptacle in your house). 14 AWG is the smallest you are allowed to use by code so we still need to use 14AWG for the 120V but we need to use 4 AWG for the 12V circuit. I have run 4 AWG wires through the walls in a house. it can be done but the cable is very expensive.

    Some day room temperature super conducters will come around. when that happens we can all hapily switch over to 12V DC and all will be great. until then you better build a really small house if you want to do it on 12V.

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  • icepuckicepuck Posts: 466
    edited 2010-06-06 03:43
    For renewable energy see
    homepower.com/home/
    For everything else see
    www.motherearthnews.com/
    -dan

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    (Former) Caterpillar product support technician
  • MarkovMarkov Posts: 19
    edited 2010-06-06 10:41
    hydrogen is a-scarce, producing it is easy but not cheap--high capital investment. Thus economies-of-scale pertain. Compared to petroleum, production of hydrogen will not be economically feasible--ever. (This is not likely to change with technological advancement significantly.) Producing hydrogen involves "spark" in production and monitoring (safety),outputs oxygen, and fuel -- hydrogen generators are affectionately dubbed "bombs". Electroylsis and containment is expensive and the safety precautions moreso.
    There is no economic and technolgically feasible alternative to petroleum. There is no petroleum (not so long-run).
    That's why there is Iraq and Afganistan (major Pipeline)--the wars of course are bad investments as far as markets goes--doesn't matter who taps the well. But it matters to wealthy individuals who then provoke excuses. God is always the scapegoat. Sometimes Markov is too.
    there are petroleum alternatives -- just no economic ones compared to petroleum which is why deep ocean drilling is economically feasible still. You can produce ethanol --early model T's had a switch to shift between gasoline and ethanol depending on what was available before infastructure matured. Ethanol production is simple and cheap (compared to hydrogen)--there are now state of the art technologies to produce ethanol form lignocellulose using hydrolysis and a synergetic complex of enzymnes (wanted to prototype this more than a decade ago using the waste stream which is more than 40 percent lignocellulose. economically feasible with a tip fee of more than $25/ton then). regardless of whether its the old sour mash fermentaion of corn upstream of the still or the latest and greaatest technology-- it takes more than 80 percent of what you produce to make ethanol--which is why it is never economically feasible (which is always a relative measure). there are currently rare short-term periods of economic feasiblity driven by low ethanol (fuel) demand and corn surpluses (~2.5 gal per bushel). Calculate the acerage to replace petroleum using maximum yields to see the impossible LED light up.
    Thus the economic crisis that has been festering for over a decade is symptomatic.
    The world will change -- will manifest as greater division of wealth (who gets to drive, keep warm or cool, and eat)-->>>increased poverty and hunger-->>>leading to more voilence expressed over resources and >>>eventually disease partly induced by negative consequences of scientific advancements in medicine (antibiotic-resistant organisms). Poverty (and war) produce human petri dish incubators. Anyone who thinks they can keep peasants from eating sick chickens has never been hungry.
    that about wraps it up.
    Markov missing a few loose screws.
  • zoopydogsitzoopydogsit Posts: 174
    edited 2010-06-06 11:28
    You should look what this Aussie company "Ceramic Fuel Cells" is doing and their products. They have some early release product, which are attracting attention in Europe and Japan. From my understanding in Japan a lot of homes use co-generation with a combustion engine turning natural gas into electricity, so in their case this technology may be a good fit. The great part about this is, that unlike solar or wind, your not dependant on the sun or weather. I've been waiting to see whether our (Australian) government will provide an incentive/rebate for this product. Currently the Australian government provides a rebate for solar.

    Their value proposition is as follows.
    http://www.cfcl.com.au/Value_Proposition/

    Though there are other interesting research into Solar as well. Have a look at the following for Australian research into polymer solar cells. We developed technology for polymer bank notes which we now export to a number of countries. They are looking at using the technology to print solar cells.
    http://www.abc.net.au/catalyst/stories/2550612.htm

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  • legoman132legoman132 Posts: 87
    edited 2010-06-07 00:10
    You could try to find a microbial fuel cell to install in a house/RV (sewage in, power+hydrogen out). Send the power to batteries and the hydrogen to a storage tank. You might need more than one house's worth of sewage though....
  • lardomlardom Posts: 1,659
    edited 2010-06-07 01:54
    I think one of the Mars rovers is still active. These robots are multiple millions of miles away and·at least one of them I believe still·obeys commands from people here on earth powered by light. This truly blows me away. It seemed logical that people could design a car that didn't rely on an explosion.·One of the things that·concerns me is that our current technology consumes oxygen faster than plant-life can replace it.·But what·seemed logical is not yet practical. I've learned from this·thread that we need oil. All I can say is that I will continue to study the subject.

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  • $WMc%$WMc% Posts: 1,884
    edited 2010-06-07 03:26
    lardom

    I hope you continue to study the subject and I hope You come up with something good! In 2004 I went through 3 hurricanes and 26 days with out power from the utility. I had to run a 5500 watt gas generator to have power,Not to mention the gas I burned going 30 miles one way to get the gas. The generator cost me about $30 bucks a day in gas. This was the most expensive power bill I ever had

    My point is that the Utilitys make power pretty cheap. Its hard to make it for less.Take a look at Your power bill and see if You can make the same power for less! If so I'll the buy power from You instead of my Utility!

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    The Truth is out there············___$WMc%___···························· BoogerWoods, FL. USA


    You can feel stupid by asking a stupid question or You can be really·stupid by not asking at all.·
  • mctriviamctrivia Posts: 3,772
    edited 2010-06-07 04:03
    Markov said...
    Compared to petroleum, production of hydrogen will not be economically feasible--ever.

    Never say never you will likely find egg on your face some day. There is already promising work in the use of Algie and photo synthesis to create hydrogen safely and economically.

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  • FranklinFranklin Posts: 4,747
    edited 2010-06-07 04:15
    Markov said...
    Compared to petroleum, production of hydrogen will not be economically feasible--ever.

    When you can't get petroleum at any price it will.

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    - Stephen
  • localrogerlocalroger Posts: 3,452
    edited 2010-06-07 17:03
    Fun fact about hydrogen: Currently the cheapest way of producing it (and the source for nearly all industrial uses, including rockets) is... drumroll please...

    They extract it from petroleum.
  • jazzedjazzed Posts: 11,803
    edited 2010-06-07 18:13
    Funny that hydrogen is the most abundant element in the universe but is so inaccessible.
    Any chance that methane hydrate could be efficiently and safely mined from the sea floor?

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  • GrampsGramps Posts: 117
    edited 2010-06-07 23:33
    Years ago i did a study on the possibility of using methane and air to power a fuel cell you could build in a 55 gallon plastic garbage can.
    Thought that methane would be pretty easy to make even in the mission field. Dump some garbage in a hole, cover it up and stick a pipe out the top.
    My main “mixer assembly” was to be catalytic converter cores. The platinum in them could catalyze the hydrogen in the methane and the oxygen in the air to make power.
    The negative side of fuel cells is that they need a pristine environment to operate in. The methane would have to be “cracked” and scrubbed and the oxygen separated from the air.
    One engineering tradeoff after another leads to lower efficiency and less power.
    The reason they work so well for NASA is that they have plenty of clean H2 and O2 on hand.
    We did build an experimental fuel cell that really worked. It ran on bottled H2 and O2. Generated a volt and a half and ran a motor that came from a Radio Shack solar cell kit.


    Gramps

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    'What is your life?"
    Saint James 61 A.D.
  • MarkovMarkov Posts: 19
    edited 2010-06-08 03:32
    Lardom: One of the beauties of ethanol is that it fits within the Carbon cycle and re-achieves balance in that the only exhaust products of its combustion are carbon dioxide and water. Its production is from plant material (lignocellulose being cheaper than the grain to make grain alcohol). An equilibria is established wherein the carbon dioxide exhaust is absorbed by the plants grown for ethanol production which 'exhale' oxygen. Despair sets in when you calculate the acerage required to produce either grain or lignocellulose to make enough ethanol to replace current consumption of just auto fuel (which is only a small piece of the energy problem) burned annually--would take every square inch of soil on the planet and then some and then soil exhaustion and salinification would set in. And there just ain't enough water (Read Cadillac Desert to get a feel for this side of things)

    Franklin: with all due respect--technical and economic feasibility are rather precise terms (Ronald Reagan codified them by executive order and those definitions tend to be taken for granted.) Technical feasiblity is a piece of cake--you can either do it or not--but it has to be proven feasible at a commercial scale--really available and not some published claim made by someone fishing for grants and such. Economic feasibility requires a reference 'voltage'. Economic feasiblity is relative to a base--which would be defined by the present cost of energy in this case--specifcally auto fuel. So the 'hypothetical fact' that hydrogen fuel might be available at some price some day when the gas pump runs dry has nothing to do with economic feasiblity. Why? is that while as i did say--alternatives will exist--but nothing will ever compare to petroleum (and its close relative coal) --it is a matter of easily refined energy density or packets you might say. and when you understand the extent that energy underlies the world economy and the short-term gift that petroleum was--then you come to understand that your descendants will not have the same standard of living as you do and that there will be rather violent adjustments (which really are already underway and they are going to get a lot worse. You do realize the stock market has been stagnant since 1998? If there was a fix to the energy situation the stock market percieved possible in the next 40 years--pretty much the horizon as far as valuation goes--the stock market problem and thus employment would not be a problem. So i would say to all the optimism is that--no body who matters (Markov is definitely not one of those) believes it. Thus, the idea of 'brute feasibility' above is a gut reaction that is actually understandable but is of little use when one tries to determine economic impacts of change. Health care debates are a distraction and won't matter either way given our situration.

    So i think what Gramps did is wonderful and interesting. Its not as Gramps says going to solve the energy problem and the point is that the energy problem is far more than a technical problem. Back in the ethanol days, the oil companies actually harassed me somewhat (Markov is numb) and tried to impress me with methanol--which like hydrogen and a lot of other things--is produced as a byproduct of petroleum these days. Methanol does have some other drawbacks--particularly its toxiciy. Dump methano in the river--all the fish die--dump ethanol in the river they get happy and beg for aspirin.

    As far as some technology that claims economic feasibility for producing hydrogen from algae--with all due respect i remain highly skeptical. And calling hydrogen safe is just insisting that obvious accidents won't happen. Not everyone who drives a car is a scientist or as bright as you folks--by a long shot. The ethanol research began years ago with a grant applied for after a similar claim was made for a new technology to 'extract' ethanol with a membrane eliminating the need for distillation (high energy input for double distillation processes). It was the first of many claims made that simply were not true --generally made by those looking for research funds, occassionally Venture Capital. Then some are professional quacks at the University of Utah who claim they just proved cold fusion technically feasible (lasted about a week). Ethanol membrane works on a lab bench but not in practice (can't produce much in the way of quantity and they neglected to mention that or take much of any of the real costs into their account for obvious reasons.) The manufacture of ethanol from lignocellulose using enzymatic hydrolysis was also claimed to be both technically and economically feasible by the Solar Energy Research Institute (SERI funded by the DOE). More grants to help put that into practice. However in doing the business planning for a prototype demonstration plant to present to venture capitalists, numerous discrepancies in SERI's claims turned up. could not get direct answers from SERI to develop a good or reasonable model--the tactics became too obvious too quick. Thus, we sort of back doored them by assuming the ideal case as far as the technology goes--the model was built assuming that production costs were free (free captial equipment) and that the production costs (variable costs tied to actual production) were zero and that the yield obtained was 100 percent of what was possible in theory. It still was not economically feasible for any production source including algae and water hyacinths (the hyacinths produce massive amounts of biomass in a relatively dense fashion and if you could scoop them up for free--the transportation, distillation, and distribution would kill ya given the economies of scale dictated by demand and capital. It would seem that with today's fuel prices some of these things would become feasible however they tend to involve so much consumption of energy to round up, process, and distribute--well--NO WAY in short--they track right along consequently. And you gradually come to understand what a gold mine--facilitated by legal definitions of property rights--an oil field is (or was). I assure you you really haven't understood the sort of numbers that an oil field/refinery deals with and the sort of economies of scale facilitated by such a dense energy source--there will never be enough algae --not to mention the problems involved with growing more -- to continue life as we know it. It is rather amazing to think about all the time invested in 'nature's production of crude--what it took to leave such a resource and then you get a sinking feeling about what we have done or perhaps the genuine stupidity and greed of mankind.

    (SERI actually had granted me $2000 to travel the business plan to venture capitalists. I sent them a copy of what i came up with--as the deliverable promised, invited them to bury the report, and never billed them for the $2000 as there was no reason to bother any venture capitalists. Was going to buy an old liquor still at auction and mine a landfill--charging a tip fee to make a prototype economically feasible but SERI didn't find that glamourous enough to suit them. Afterall, what they were looking for was material that would look attractive to continue their efforts in the lab despite that they were in essence done.)

    As far as egg on my face -- Markov wears egg well enough. Markov generally has little to say. But we are at the end of an era and techology has brought as many problems as it has fixed. The powers-to-be like to reassure you by promoting alternatives--things will be alright. Things to distract you. Markov has many names--some say a Cad. Well, if you know the House, then it is the role of the Cad to turn you around to look at the future. Generally nobody wants to listen--that's the point of the myth--what happens to Act-a-eon and Tireseas. By the myth, you see it is Truth who is a Terrorist (the emperor is always naked but says who is a Terrorist). Gas prices have near tripled, unempolyment has skyrocketed, the world economy is going down the tubes, the cost of eductation is out-of-reach. War is looming everywhere you look and the crisis is just getting started.

    it is a good question. Its the answer that's not so good. You can blame Markov but it won't fuel your car, make your chips, .... In summary, i don't have a clue...about what to do only first i know you can't solve a problem until you have defined it properly. The officer asks the mechanic how long it will take to fix an air compressor. The mechanic says 30 minutes. Six hours later the officer is back in the Engine Room pestering the mechanic who's still working on it. How long now? "30 minutes". Six hours later: The Captain is about to have my ..., I need to know really how long it will take you to fix this thing? The mechanic says: I assure you sir with all due respect that once i figure out what the problem is, i can fix it in 30 minutes.
  • GrampsGramps Posts: 117
    edited 2010-06-08 21:49
    Me thinks that the electric car industry is going to be producing some very nice surplus goodies soon, whether they go boom or bust.
    Especially lithium batteries are looking good!
    It will be great for guys like me on the bottom of the electronic food chain......


    Gramps

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    'What is your life?"
    Saint James 61 A.D.
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