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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...
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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.Ivan Seeking said: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!
mheslep said:Fuel cell charges the batteries.
Ivan Seeking said: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!
Yes you beat me to it; I guessed low for the average, nice work, That agrees w/ this http://mb-soft.com/public/headlite.html" . 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.Ivan Seeking said: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.
Yes, and http://www.teslamotors.com/performance/perf_specs.php"chemisttree said:Can you imagine a car running on a 100 HP electric motor? That would truly be a funny sight!
3-phase, 4-pole electric motor, 248hp peak (185kW), redline 13,000 rpm, regenerative "engine braking"
Ivan Seeking said: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.
mheslep said:Yes, and http://www.teslamotors.com/performance/perf_specs.php"
Click http://www.teslamotors.com/design/under_the_skin.php" here for a picture.
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 http://www.acpropulsion.com/"chemisttree said: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.
http://www.technologyreview.com/Energy/17644/...But among the various challenges to developing the technology, manufacturing cost has been a potential deal breaker. Now, researchers at GE have demonstrated a manufacturing method that assembles layers of ceramic and electrolyte materials cheaply so that the final product can be built for about $800 a kilowatt, which starts to approach the $500-to-$550-per-kilowatt cost of building a conventional gas-fired power plant.
GE's six-kilowatt prototype achieves 49 percent efficiency in converting fuel into electricity, which compares favorably with the 35 percent efficiency of conventional coal-burning power plants. [continued]
chemisttree said: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.
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.Ivan Seeking said:I must say, this new technology is very exciting!
http://www.technologyreview.com/Energy/17644/
That is a vast improvement!
Best of luck. Please post up how its going from time to time.I'm working on the hydrogen from algae problem as fast as I can!It may help that the folks at MIT are as well.
Insurance co.'s could test the car much more economically, or assess it as is and issue riders.That "if and when" is proving problematic. This green machine was originally due to hit the road this month. But that tricky transmission and other mundane issues for major automakers—like crash-testing the cars—are taking longer than the neophyte auto moguls expected. It now looks like customers won't get their cars until early next year. "I had a friend cancel his order because he didn't want to wait," says Chris Paine, the director of "Who Killed the Electric Car?" who still has his deposit down
Why would you do that? The fuel cell is the battery.mheslep said:Fuel cell charges the batteries.
mheslep said: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.
See above. Fuel cells, even Solid-Ox, are too expensive and too large at the 200HP scale to fit into a car, even an exotic car >$100k. However, a ~30HP cell is doable both economically and technically, and ~30 HP is all you need to maintain average road speed. Then, since 30HP doesn't give you much giddy up, add traditional batteries to raise the hybrid's peak power up to common car ICE peak power. The reason for this hybrid approach is the relatively low http://en.wikipedia.org/wiki/Energy_density" of battery technology vs hydrocarbon fuel. HC fuel gives you 10 to 143 Mj/Kg, where as the best batteries are ~1Mj/Kg, ie 100:1. Then for power output in KW per dollar, batteries out perform fuel cells by a similar multiple. Thus the hybrid fuel cell + battery approach.russ_watters said:Why would you do that? The fuel cell is the battery.
In the US 220 mi (and that's with new batteries) won't do it. No, that range is for commuters (and the tech is too expensive for that) or out and back trips. The problem is you can't 'fill er up' anywhere with stopping ~over night. See above. A 20 L tank of gasoline is 680mega joules. Recharging that amount of equivalent electrical energy in 5 mins as is common now with gas would require a 680Mj/300s = 2.2MW electrical charge capability per pump. Thus a regular filling station would have to be a 20MW generating plant. Not going to happen.Argentum Vulpes said:With a range of 220 miles between charges I'd say the Tesla roadster has some decant legs on it. Granted in some parts of the country that is not enough to get to the next major city.
Yes agree hybrid is the right approach, just not ICE + battery hybrid as you're still wed to oil.Or another approach is that of the Chevy Volt. It is setup like the big diesel trains running today. Electric motors provide the power for driving, a diesel motor spins a generator to provide electricity. The Volt's drive train is similar except the car has a battery pack to provide some gas free miles. When the battery pack runs down, an engine hooked up to a generator provides power to the electrical system to keep the car moving.
Except the tech. doesn't exist, at least not in any 'evolutionary' better than present tech form.The next evolution step in battery systems is replacing the Li-ion pack or some other exotic and/or new battery pack with an ultra capacitor system. Basically it is just what it sounds like, a large bank of capacitors.
No, as per above that will never happen, at least not with a 'bam'. Maybe with a 'zzzzzzzz'.When the charge runs down pull into a charging station, plug it in and bam you are ready to go again.
And before anyone says that this technology is a pipe dream with no possible future. http://www.colemanflashcellscrewdriver.com/". Can't get there from here. Most promising battery tech appears to be Li ion w/ nanowires - 6Mj/Kg
Good question. The fuel cell related latency would be in the hydrogen transport time across the membrane, i.e. the answer would come from some kind of diffusion analysis. The search for designs w/ higher power per volume and weight often concentrates on improving the power vs diffusion rate; I'm guessing that has the side effect of also reducing the transport time. Also, because I don't see mass H2 distribution occurring, we must also consider lag in the onboard HC reformulation. To stop that from adding to throttle to power lag we'd want more hydrogen storage, etc = more $.chemisttree said:Without the battery, can a fuel cell react to throttle inputs quickly and with low energy waste? I don't think so.
Fast fuel delivery is an issue dealt with now in ICE cars. The fuel system design requires attention but tenths of second are common there (to deliver the fuel, spinning up the ICE moments is another issue). In any case, agreed, the hybrid fuel cell + low cost electrical energy buffer obviates all those problems.chroot said:...Another major problem with using a fuel cell for direct drive is not the fuel cell's membrane -- it's all the air compressors and fuel delivery mechanisms that would need to spool up in order to deliver more power. If you stomp on the pedal and get power three seconds later, it'll never attract a single buyer.
Have the old problems ever been worked out of flywheels? There were the bus experiments that never went very far. Some of initial promise was that the exorbitant weight problems (3T bus required a 3T flywheel) would be solved by high rpms w/ high tensile strength disks but those could never be made safe enough without a high strength enclosure and we're back to exorbitant weight again. Then there was the effect of angular mo. on handling. I'd heard of the compressed air car in India but know nothing about it. The keys for a transient high power source to well complement a f. cell are good KW/Kg and KW/$ ratiosYou can avoid batteries with other kinds of energy storage. Flywheels and compressed air are two kinds of non-electrical storage technologies that could be mated to a fuel cell to provide an energy buffer.- Warren
Argentum Vulpes said:The next evolution step in battery systems is replacing the Li-ion pack or some other exotic and/or new battery pack with an ultra capacitor system. Basically it is just what it sounds like, a large bank of capacitors. When the charge runs down pull into a charging station, plug it in and bam you are ready to go again.
And before anyone says that this technology is a pipe dream with no possible future. http://www.colemanflashcellscrewdriver.com/", we get 25MJoules and you could keep your foot to the floor for ~3mins. The commonly available ultracaps from Maxwell Tech are rated at 0.01 Mjoules/Kg - if that's all that can be done economically ultracaps are out.
The ultracap's has some other advantages over batteries: short charge time (batteries 10:1 charge:discharge), temperature insensitive.
The round trip commute you suggest is all you'd be able to do. You couldn't go on any long trips without stopping every three hours to recharge for five, at least w/ batteries. Ultracaps may help that. Anyway, the thread topic is fuel cells, ostensibly because a) everyone likes the fact that they move all the HC pollution back to a central power plant and b) they're more efficient than any heat cycle engine.RonL said:Out of 24 hours, if only 2 or 3 are being used for travel, then a small, well engineered diesel engine, of small horsepower, can drive a generator at a steady speed recharging and maintaining the battery state of charge. It would run continually (24 hours a day) with charge rate being controlled as is common practice today. My thoughts are that it would be much like the refrigerator in a home, cycles would be longer and speeds would be governed by charge demand. For auto's that are not used every day the engine might even be shut down completely.
A separate auto might be needed for more extensive use, but for a serious reduction in energy demands, the mindset of the majority needs to reshaped.
mheslep said:Anyway, the thread topic is fuel cells, ostensibly because a) everyone likes the fact that they move all the HC pollution back to a central power plant and b) they're more efficient than any heat cycle engine.
Chemistree posted this graph up thread on driving http://www.metricmind.com/line_art/us06_us.gif" .RonL said:Looking thru the thread, i see a lot of good comments, and a few links that provide a lot of information for study.
One point of view that i don't see, is that of how we use our vechicles. ...