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Elon Musk Calls Hydrogen Fuel Cell Cars ‘Bullshit’

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Re: Elon Musk Calls Hydrogen Fuel Cell Cars ‘Bullshit’

#21
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Man with billions invested in electric cars disparages competing technology? I am shocked. The fact is, you don't need to have a high energy density with hydrogen, as existing gas stations can be used to quick refuel a hydrogen car (with robotic assist, perhaps), without the logistical mess that comes from swapping an extremely heavy, very expensive, potentially user-abused battery with another one. You can even burn…

I'd give Elon Musk more credit than generic CEO spin for this. If he thought hydrogen was viable, he'd be working on it.

I give Musk a bit more credit than most CEOs, but he has also shown himself to be very capable of playing the spin game in the press recently (the funky math on the 'new finance product', declaring that the NYT backed off its Tesla piece when they in no way did).

Re: Elon Musk Calls Hydrogen Fuel Cell Cars ‘Bullshit’

#22
post #16
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IMHO hydrogen fuel cell technology is more practical. No charging time means that you can travel any range without delays as long as you have hydrogen fuel stations on your way. That kind of technology gives you more freedom I guess. You feel less limited by your vehicle. And as far as I know charging li-ion batteries is still very slow, they will go flat at some point, faster you are charging them faster they become…

Charging time is overblown. You can charge a modern battery to 80% in about 5 minutes. That's about how long it takes to fill my car with gas at the moment. You're not going to be refueling a hydrogen fueled car that quick - it's a volatile, extremely high pressure, extremely cold gas. The safety considerations are substantial .

Ok, what about durability of batteries compared with durability of fuel cell? I'm just curious because I think that batteries are less durable right now than fuel cells.

Re: Elon Musk Calls Hydrogen Fuel Cell Cars ‘Bullshit’

#23
post #8

There are many technical problems with hydrogen: metal embrittlement, it leaks even through solid substances, etc. They're not insurmountable, but they make hydrogen not that competitive with electric. Elon is not a fan of H2 for rockets either for those very same reasons-- embrittlement, leakage, cost of storage and handling. Guy is flat out anti-hydrogen, man. That and once you have hydrogen it's not that hard to g…

Pretty much this. Handling pure hydrogen is a suckers game in terms of complexity. The real problem is we don't have a compact, low temperature direct methane/direct methanol/ethanol fuel cell yet.

Re: Elon Musk Calls Hydrogen Fuel Cell Cars ‘Bullshit’

#24
post #14

Earlier quoted context omitted.

And how much energy is lost converting energy to hydrogen? Because there are no native hydrogen energy stores. You're either using electricity to crack water, or you're going to crack natural gas. Its more efficient to simply use batteries. EDIT: I'd like to point out, generating hydrogen does make sense if you're using an energy source that is essentially free. Too much hydro and you have to dump the water anyway? M…

source? edit: that link doesn't really say that hydrogen is less efficent than batteries, just that it has less energy than the energy content of the original fuel, which is true with charging a battery too because of transmission losses, ect.

Nature? Free hydrogen doesn't really exist on earth; atmospheric hydrogen is something like 1 ppm. There's tons of hydrogen on earth, but it's all in water and hydrocarbons, which you have to split to get to the hydrogen itself.

The Wikipedia article on water splitting notes that "production of hydrogen from water requires large amounts of energy and is uncompetitive with production from coal or natural gas." If you're capturing it as a byproduct of an existing process, then it probably makes sense, but just applying electricity to water to generate hydrogen to burn isn't very economical right now.

Re: Elon Musk Calls Hydrogen Fuel Cell Cars ‘Bullshit’

#26
post #2

Man with billions invested in electric cars disparages competing technology? I am shocked. The fact is, you don't need to have a high energy density with hydrogen, as existing gas stations can be used to quick refuel a hydrogen car (with robotic assist, perhaps), without the logistical mess that comes from swapping an extremely heavy, very expensive, potentially user-abused battery with another one. You can even burn…

And how much energy is lost converting energy to hydrogen? Because there are no native hydrogen energy stores. You're either using electricity to crack water, or you're going to crack natural gas. Its more efficient to simply use batteries. EDIT: I'd like to point out, generating hydrogen does make sense if you're using an energy source that is essentially free. Too much hydro and you have to dump the water anyway? M…

I know, we'll get it from the atmosphere of Jupiter!

Re: Elon Musk Calls Hydrogen Fuel Cell Cars ‘Bullshit’

#27
post #16
post #9

IMHO hydrogen fuel cell technology is more practical. No charging time means that you can travel any range without delays as long as you have hydrogen fuel stations on your way. That kind of technology gives you more freedom I guess. You feel less limited by your vehicle. And as far as I know charging li-ion batteries is still very slow, they will go flat at some point, faster you are charging them faster they become…

Charging time is overblown. You can charge a modern battery to 80% in about 5 minutes. That's about how long it takes to fill my car with gas at the moment. You're not going to be refueling a hydrogen fueled car that quick - it's a volatile, extremely high pressure, extremely cold gas. The safety considerations are substantial .

At what amperage and voltage and how much did it cost to upgrade the charging station connection to the grid.

And how do you cool the battery during such a fast charge? what % of the energy is lost in heat from the chemical reaction - even Tesla has to obey the laws of thermo dynamics.

Thinking about it from a thermofluids angle You could I suppose have a complex system of heat exchangers built in to the the battery pack and hook the car up to a water connection and flush chilled water (or better some non conductive fluid) through whilst charging but water and high voltage and amps are not the best of friends.

Now where did i put my steam tables :-)

Re: Elon Musk Calls Hydrogen Fuel Cell Cars ‘Bullshit’

#28
post #2

Man with billions invested in electric cars disparages competing technology? I am shocked. The fact is, you don't need to have a high energy density with hydrogen, as existing gas stations can be used to quick refuel a hydrogen car (with robotic assist, perhaps), without the logistical mess that comes from swapping an extremely heavy, very expensive, potentially user-abused battery with another one. You can even burn…

And you can use wind/wave/solar energy that is "spare" to crack hydrogen for storage. The ability to use effectively the same engines and plant is a big plus for hydrogen.

It's more efficient and simpler to use that spare energy to pump water uphill:

http://en.wikipedia.org/wiki/Pumped-storage_hydroelectricity

Re: Elon Musk Calls Hydrogen Fuel Cell Cars ‘Bullshit’

#29
As an interesting aside, the leading use for hydrogen today, with over 50% of all hydrogen used, is in oil refining. That hydrogen (along with almost all the balance) comes from steam-reformed natural gas.

It's also true that more electricity is consumed refining gasoline (without even figuring the oil itself's energy) than in producing hydrogen (per gge). The important distinction is that gasoline is an outstanding motor fuel, able to deliver 3000x the volumetric energy density of hydrogen gas, 6x the volumetric energy density of compressed hydrogen and 3x the volumetric energy density of liquefied hydrogen.

Those numbers get even more stark when you add in tank weights.

Musk's Youtube video demonstrates a battery changeout faster than a gasoline fillup (BTW, ever filled up a tank with H2? It's not as fast as gasoline per gge; not even close).

I share the BS opinion on hydrogen fuel cells. Hydrogen tanks cost too much, weigh too much and better alternatives exist.

Re: Elon Musk Calls Hydrogen Fuel Cell Cars ‘Bullshit’

#30
post #12
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There are three pressing concerns for hydrogen fuel cells, which can be added up to "bullshit". First, energy density. I can't speak to that in detail, but the range problem is serious. Then again, the range problem seemed insurmountable for electric cars until Tesla got within spitting distance. Second, platinum. Traditional hydrogen cells require some platinum in the catalyst, which is fine at lab scales, but unvia…

It applies to gasoline cars too, you need energy to process oil into gasoline.

Oil is a net positive on the energy, even with the energy cost to refine it. Generating hydrogen from water is a net negative on the energy, guaranteed, by thermodynamics.

Unless we start stealing it from an extra-planetary source, it is best to think of hydrogen as a battery, not a fuel.

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