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jim_t
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Re: Are auto companies seeing limitations in EVs?
jim_t   7/3/2013 9:27:18 AM
Hydrogen cars are among the least efficient, least cost-effective means of reducing CO2.

Our hydrogen supply today is made by methane reformation.  Converting methane to hydrogen, and then using that hydrogen in a fuel-cell car, is wildly more expensive *and* less energy-efficient than just running a conventional IC engine on compressed natural gas. 

Honda's figure "driving energy" conveniently excludes the issues associated with hydrogen production.  Otherwise their exising CNG vehicles would outperform the wildly more expensive fuel cell "car of the future".  And in the future, sure, we could make hydrogen from water with wind or solar power.  But if we're starting with (renewable) electricity, battery systems wildly outperform the energy-efficiency of hydrogen -- at least 2x more miles driven per starting kWh.

Battery recharge rates, storage capacity per volume and per dollar, and lifetime are improving every year.  And for that matter Tesla just demonstrated 90 second pack swap -- in and out of the supercharger station faster than filling an Audi with gasoline, and vastly faster than a hydrogen recharge.  Not quite Moore's law but a solid curve.

Battery-electric vehicles offer essentially zero-CO2 transportation, powered by wind or solar power, today.  Net CO2/mile even if you're running on coal-fired electricity is better than any hydrogen system right now, and running on gas-fired CCGT power (>50% efficient at the power station, rather than 20-30% efficient at the vehicle) is again the lowest cost/mile and lowest CO2/mile -- with transition to zero-carbon as fast as we decide to decarbonize the grid.

"Technology of the future... and always will be."  This stuff might be fun to write about but the fundamentals remain the same.

jim_t
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Re: Are auto companies seeing limitations in EVs?
jim_t   7/3/2013 9:27:14 AM
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Hydrogen cars are among the least efficient, least cost-effective means of reducing CO2.

Our hydrogen supply today is made by methane reformation.  Converting methane to hydrogen, and then using that hydrogen in a fuel-cell car, is wildly more expensive *and* less energy-efficient than just running a conventional IC engine on compressed natural gas. 

Honda's figure "driving energy" conveniently excludes the issues associated with hydrogen production.  Otherwise their exising CNG vehicles would outperform the wildly more expensive fuel cell "car of the future".  And in the future, sure, we could make hydrogen from water with wind or solar power.  But if we're starting with (renewable) electricity, battery systems wildly outperform the energy-efficiency of hydrogen -- at least 2x more miles driven per starting kWh.

Battery recharge rates, storage capacity per volume and per dollar, and lifetime are improving every year.  And for that matter Tesla just demonstrated 90 second pack swap -- in and out of the supercharger station faster than filling an Audi with gasoline, and vastly faster than a hydrogen recharge.  Not quite Moore's law but a solid curve.

Battery-electric vehicles offer essentially zero-CO2 transportation, powered by wind or solar power, today.  Net CO2/mile even if you're running on coal-fired electricity is better than any hydrogen system right now, and running on gas-fired CCGT power (>50% efficient at the power station, rather than 20-30% efficient at the vehicle) is again the lowest cost/mile and lowest CO2/mile -- with transition to zero-carbon as fast as we decide to decarbonize the grid.

"Technology of the future... and always will be."  This stuff might be fun to write about but the fundamentals remain the same.

junko.yoshida
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Re: Are auto companies seeing limitations in EVs?
junko.yoshida   7/3/2013 8:36:23 AM
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As you pointed out, storage solutions appear to be the issue --- but that's the case with not only hydrogen cars and EVs. 

The quesiton is who gets to solve this faster...

jkocurek
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Re: Are auto companies seeing limitations in EVs?
jkocurek   7/3/2013 8:16:45 AM
I think the reason why development has slowed for fuel cell autos is the hydrogen storage problem. An aqueous solution of sodium borohydride can have a similar energy density as gasoline. It is reasonable non-toxic, non-explosive, it doesn't burn and is stable. A little catalyst and it releases its hydrogen and leaves behind sodium borate, i.e. borax. The problem is production. Ideally you should be able to react hydrogen with the sodium borate to reform the sodium borohydride. But so far it cannot be done economically.


Pretty much all of the other storage solutions are technically challenging, expensive, risky or some combination of the three. I think the auto industry would prefer to wait until the sodium borate -> sodium borohydride problem is solved.

krisi
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Re: Fuel cell plus a reformer?
krisi   7/3/2013 12:16:54 AM
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Good luck pumping your elecrtolyte into your battery...let me mention one word, liabilities!

junko.yoshida
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Re: Are auto companies seeing limitations in EVs?
junko.yoshida   7/2/2013 10:14:26 PM
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I hear you, Kris. I understand. But here's the thing. Despite some progress made in hydrogen cars earlier, why does it feel like that the technology development in hydrogen cars had been dormant or slowed down in the past decade,,,  Is that because the auto industry shifted their interest more to EVs?

Bert22306
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Fuel cell plus a reformer?
Bert22306   7/2/2013 8:23:52 PM
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I did read about a scheme in which you pump fresh electrolyte into the battery, to achieve a full charge in the time it takes to refuel standard cars. Not sure where that went.

Failing that, I've always thought that fuel cell cars have a brighter future. But hydrogen in a tank does not. It's very volatile, has the teensiest atoms, and these tanks therefore deplete themselves as fast as, or maybe faster than, batteries die when left without recharging.

Besides, how disingenuous is it to say that fuel cell vehicles are pollution-free? Surely, that depends entirely on how you produce the H2 they need. From coal-fired electric plants, they pollute at least as much as ICE cars.

I put my hopes on separating the H2 from a fuel, stored in the car, in a regular fuel tank. The entire process should easily be twice as efficient as internal combustion engines are, and more efficient than that at low power levels, such as city driving. So that's how you cut the CO2 emissions. I mean, the typical 30 percent figure we see for ICE applies only at the best operating modes. In typical driving, try something in the high teens and twenty percent ranges. A fuel cell should be on the order of over 50 percent. The reformer should be way higher than that.

krisi
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Re: Fuel Cell As Replacement to Lithium Battery
krisi   7/2/2013 8:01:18 PM
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The number 1 battery swap company just went belly up...so much for the good idea in theory but poor in practice that neglects reality of consumer behaviour...who would want to swap EV batteries instead of just umping gas???

chanj0
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Re: Are auto companies seeing limitations in EVs?
chanj0   7/2/2013 7:48:28 PM
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Addition: Honda has been putting a huge bet on fuel cell vehicle, believing hybrid does not have the long term future. They pulled the plug as soon as Obama cut the funding in 2009. I am glad to hear Honda is coming to the game again.

chanj0
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Fuel Cell As Replacement to Lithium Battery
chanj0   7/2/2013 7:40:46 PM
There is no doubt one of the biggest challenges to EV is recharge rate. There is all kind of solution coming up lately. Fast charging and Battery swap. Yet, there doesn't seem to be anything as fast and as convenience as pumping gasoline. What if a fuel that can be injected into a battery get a recharge? Neglecting production and transporation of hydrogen fuel,  I believe fuel cell might actually be able to contribute to our energy future, especially as an alternative fuel to vehicle.

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