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Hydrogen fuel cell cars

  1. Jan 24, 2008 #1
    Enuma's thread got me thinking why these isn't more buzz for the hydrogen cars like the Honda FCX, GM Sequel, Nissan Frontier, BMW 7...
     
    Last edited: Jan 24, 2008
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  3. Jan 24, 2008 #2

    russ_watters

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    Probably because they are nowhere close to production ready and the infrastructure to support them is years away as well. Plug-in hybrids just made some news. They are still a couple of years away and have a couple of hurdles to overcome (battery cost/life/weight), but at least they look like they might be viable. Fuel cell cars may not ever be viable. The enabling technologies to get over the remaining economic/engineering hurdles don't exist and don't appear to be close to happening.

    They do get a little buzz, though. Some see them as the holy grail of auto technology.
     
  4. Jan 25, 2008 #3

    Ivan Seeking

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    This is the worst of it.
    http://www.fuelcellstore.com/en/pc/viewPrd.asp?idcategory=53&idproduct=889

    Although not entirely representitive of the price for a car, here we can get a 1KW fuel cell for about $24,000. 1KW = 1.34 HP. At that price, a fuel cell capable of producing enough power to replace a lawn mower engine would cost $50,000.

    I have found 1KW cells for half that price before, but when we consider that even a small car may produce 100 hp, the price for the same in fuel cell power becomes absurd - about a million bucks!
     
    Last edited: Jan 25, 2008
  5. Jan 25, 2008 #4

    russ_watters

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    As I understand it, the reason for this is right now a fuel cell requires exotic materials like platinum and palladium.
     
  6. Jan 25, 2008 #5

    mheslep

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    I got into this area for work last year. Fuel Cell Store appears to be mainly for do it yourself-ers but I spent some time there pricing a house backup system (for myself) . Just for the PEM stack, no fuel supply or reformulation, no inverter, I came in at about $2k per kw. YMMMV.
    Fuel Cell store is mostly about traditional ~low temperature PEMF platinum based cells which as Russ suggested are going to be expensive, probably always will be. For KW level power the hot fuel cell tech. now is solid oxide which because of its high temperature (700-1000C) doesn't need the $$$ catalyst, and a vehicle sized platform can be hold the necessary thermal management bulk. Also, note that a vehicle fuel cell probably only has to provide average HP (3? 4? ) and peak HP (~100) can be provided by battery assist. I'd say the biggest problem now for fuel cell cars is the hydrogen delivery / infrastructure, not the cell technology anymore - Energy cost of liquefying H2, can't put H2 gas through the pipelines, etc, etc.

    Edit: average HP is 10x too low as noted by Ivan. Should be >30HP.
     
    Last edited: Jan 25, 2008
  7. Jan 25, 2008 #6

    Ivan Seeking

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    I don't see a car running on 3 or 4 HP; at least not one that anyone would buy. That is the same power that one finds in a small moped. And how do you get battery assist from a car that has no recharging system?
     
  8. Jan 25, 2008 #7

    mheslep

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    Fuel cell charges the batteries. BTW, here's a gorgeous example of what battery power can do when you need that 'peak'. 248HP, 0-60 < 4secs, top speed 125mph.
    http://www.teslamotors.com/design/gallery-body.php. Line for beta testing the next model forms behind me.
     
    Last edited: Jan 25, 2008
  9. Jan 25, 2008 #8

    Ivan Seeking

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    I just did a quick calculation based on a car that gets 40mpg at 60 mph. Factoring in 40%efficiency for the engine, 90% efficiency for an electric car, and 125 kBTU per gallon of gasoline, I get a mininum of 24 KW; or 32 HP just to roll down the road.
     
  10. Jan 25, 2008 #9

    Ivan Seeking

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    Then you need more fuel cells to provide the charging. There are no free lunches.

    I think you also have to derate the batteries by about 50% to account for efficiency.
     
    Last edited: Jan 25, 2008
  11. Jan 25, 2008 #10

    chemisttree

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    Are you saying that you couldn't cut your grass with a self-propelled lawn mower that had a 1.34 HP motor? From my calculations, you need about half of that fuel cell's output to power an electric mower (24V at 12 amps).

    The price per kilowatt of the most employed fuel cell currently used is between $3,000 and $4,500 per kilowatt. And... you cannot scale horsepower to electric power as you have done. Can you imagine a car running on a 100 HP electric motor? That would truly be a funny sight! A 30 to 50 kW electric motor is perfectly acceptable to power a Honda-sized vehicle. Price for that (if it were available) would be closer to $120,000. If the DOE's program to lower the cost to about $400 to $500 per kW is achieved, the price is cut to a (reasonable?) $12,000! Still pretty high but not out of the range for an fuel cell/battery hybrid vehicle which could use much smaller fuel cells.
     
  12. Jan 25, 2008 #11

    mheslep

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    Yes you beat me to it; I guessed low for the average, nice work, That agrees w/ this site.. Add another HP or two to charge the batteries in the background. So a practical target cost then is perhaps $1k/10kw for a solid oxide cell. Edit: since there's no $$ catalyst, I expect that is doable.
     
    Last edited: Jan 25, 2008
  13. Jan 25, 2008 #12

    mheslep

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    Yes, and more than that.

    Click 'motor' here for a picture.
     
  14. Jan 25, 2008 #13

    chemisttree

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    But here is what is actually being done....

    http://www.metricmind.com/ac_honda/main2.htm

    That approximately 30 kW is about what is used on average for acceleration and rolling down the road. The inverter used limits the maximum power to 80kW for brief periods of acceleration but you can just about estimate that roughly 10 to 15 kW is used to maintain speed at 100 km/hr. The US06 drive cycle was used which has a constant speed of roughly 100 km/hr between 200 seconds and 275 seconds. The graph is here.
     
  15. Jan 25, 2008 #14

    chemisttree

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    That's a little more than a small 100 hp comparison there.... 0 to 60 in under 4 seconds! Yeah! Sign me up as well!
     
  16. Jan 25, 2008 #15

    mheslep

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    Yes the power conversion electronics, not the motor, are probably the technically most challenging part of the electric drive train. They licensed the charging electronics integration into the inverter from AC Propulsion, and built the inverter themselves.
     
    Last edited: Jan 25, 2008
  17. Jan 25, 2008 #16

    Ivan Seeking

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    I must say, this new technology is very exciting!

    http://www.technologyreview.com/Energy/17644/

    That is a vast improvement!!!

    I'm working on the hydrogen from algae problem as fast as I can! :biggrin: It may help that the folks at MIT are as well.
     
  18. Jan 25, 2008 #17

    Ivan Seeking

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    Yes. My lawnmower is 5HP and barely has the power needed in spring. Of course I live in Oregon.

    Source?

    It is called conservation of energy.

    That is part of the point.

    That has yet to be determined. It is a consumer driven market.
     
  19. Jan 25, 2008 #18

    Ivan Seeking

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    Of course, if you are driving a biodiesel powered car, all of this goes away. You still get 100+ hp for the same price as a gasoline engine, and you pay about $3 a gallon for fuel. No infrastructure problem, no price problem, no power problem.

    Later we can go to algae produce hydrogen - internal combustion. No need to drive go-carts.
     
    Last edited: Jan 25, 2008
  20. Jan 25, 2008 #19

    mheslep

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    Thanks for the link. I couldn't tell from the description of that So-Ox rack shown there how much of the volume and cost is allocated to reforming the hydrocarbon fuel down H2. I think the reforming bulk would have to go for a vehicle size unit.

    Best of luck. Please post up how its going from time to time.
     
  21. Jan 25, 2008 #20

    mheslep

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    Best article Ive found on the Tesla.

    Newsweek, October '07
    "An Electric Dream"

    Guess who's helping to hold up the electric car now? The government.
    Insurance co.'s could test the car much more economically, or assess it as is and issue riders.

    They go on to say that they plan to go from being a niche sports car to a mass market model, which I believe is foolish w/ a Li ion battery powered car. They'll never build a model that will go on long trips. Can't fill 'er up. Got to have fuel cells and hydrogen/hydrocarbon fuels to make the pure electric play work.
     
    Last edited: Jan 26, 2008
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