samboct
Posts: 1817
Joined: 1/17/2007
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Just saw this article...the demise of fuel cells in future technologies may have been somewhat exaggerated....
http://www.sciencedaily.com/releases/2011/04/110404110417.htm
So what's going on here?
There are two types of fuel cells that have been contemplated for vehicle applications (let's not get into stationary power) Proton exchange membrane (PEM) and solid oxide fuel cells (SOFC).
PEM fuel cells have been developed by Ballard and use hydrogen as a fuel. There have been a bunch of stumbling blocks- getting hydrogen clean enough to use, getting a membrane that has a decent lifetime, finding a catalyst that's less expensive than platinum etc.
Solid oxide fuel cells can utilize a variety of fuels- including hydrogen, but they can also use liquid fuels like methanol. Yes, they give off some CO2 if they do so, therefore, the methanol source needs to be carefully evaluated to be carbon neutral- but methanol is really not a bad thing to make from bio sources-its much easier than ethanol and doesn't soak up water as well.
Anyhow, solid oxide fuel cells have been either done on a micro scale- i.e. used to power a cell phone with a methanol cartridge, or on a much larger scale used to power buses. The problem with the smaller scale fuel cells is that they're small- but they turn on rapidly, can be quickly refueled, and have much higher energy density than batteries- at least an order of magnitude and maybe more. The problem with the big block fuel cells in buses is that since they run rather toasty- i.e. typically 700C plus, they talk a long time to get up to temperature (at least an hour) and they generate an awful lot of waste heat.
These new solid oxide fuel cells combine some of the advantages of both technologies- they run at lower temperatures- less than 500C, can handle a variety of liquid fuels (in all likelihood), and they should come up to temperature rapidly.
If they can be manufactured cheaply enough-this may be the technology that buries the internal combustion engine. It'll have the advantages of an IC engine- i.e. can be rapidly fueled which may make the goddamn oil companies heave a sigh of relief- they can switch over to selling methanol instead of gasoline (and these cells can probably use gasoline as well depending on the reformer), and it'll have the range of a current gasoline powered vehicle if not more. If the power density is acceptable- then batteries are in trouble. If not, well, then this technology will offer a range extender for a battery powered vehicle. Either way- assuming these things can be built inexpensively enough, the internal combustion engine is in trouble.
Sam
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Fuel Cells back in the game... - 
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