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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 hydrogen in an ICE engine, as BMW has demonstrated.

The Honda Clarity FCX, a hydrogen powered car, is the only other car to achieve Type V California ZEV credits besides the Model S. Perhaps that's too much competition for Musk. The range of that car is 240 miles.

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Yes, I was hoping the article actually shared some of the research Tesla must undoubtedly have done about the feasibility of fuel cells. Yes, they have limited range, but so do batteries. But while it takes _hours_ to recharge a battery, refueling hydrogen takes a couple of minutes, same as petrol.

All his other arguments about infrastructure and safety apply equally well to petrol cars, and yet here we somehow managed to implement that efficiently. I don't see any inherent reason why we can't do the same for Hydrogen.

Teslas do not take hours to charge when Superchargers are taken into account. The Superchargers can charge 50% in 30 minutes (80% in 40 minutes)[1].

[1] http://www.teslamotors.com/supercharger

Tesla plans to create battery-swapping stations that switch battery packs faster than filling an empty petrol tank, which can mitigate recharging.

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? Make hydrogen. Too much wind and the transmission operator is shutting down your production? Make hydrogen. Otherwise, it doesn't make sense to use it as an energy transfer medium.

http://en.wikipedia.org/wiki/Hydrogen_economy#Current_produc...

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.

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

With a fleet of SpaceX Falcon Heavies?

I know this is somewhat tongue-in-cheek, but what would the long-term consequences be of importing large quantities of hydrogen from off-planet and then binding it to local oxygen?

I suppose if we had the tech to do that, we might be able to find off-planet oxygen as well...? Except wasn't most of ours produced by plants splitting carbon-dioxide?

More water vapor, which is also a greenhouse gas. It's quite a bit more potent of one than CO2, in fact.

So water electrolysis has losses of 50-80%. And then you need to transport it to refueling stations (which could be pretty high). Edit: forgot the obvious, the losses in the actual fuel cell. 40-60%. Yeah that equation doesn't add up.

What losses to we have on the battery end? Transmission line losses (6%), li-ion charge/discharge losses (80-90%), losses due to the fact that the car needs to keep the battery warm/cool depending on outside temperature (pretty high in the winter, regular 120V outlet is not enough to keep the capacity up).

Personally I dismiss hydrogen mostly because I'm frightened by the thought of a bunch of high pressure fire bombs being driven around by drunk people.

One possible solution is renewable energy.

All current renewable energy sources have one big flaw. They produce energy when the circumstances are right, not when required. Beacause of this they cause issues in the energy grid.

If we could build water cracking facilities at the right scale with the right characteristics, that could help offset the efficiency/cost issues.

And on the issue of high pressure fire bombs, gas powered cars are pretty common here in Europe and those things are pretty safe. There are numerous safety features, not to mention that gas tanks are pretty tough vessels.

Edit: On the topic of fire bombs. I have today learned that one would not want Hydrogen tank in his vehicle.

>Edit: On the topic of fire bombs. I have today learned that one would not want Hydrogen tank in his vehicle.

Everyone comes to this conclusion when you realize how deadly compressed hydrogen is compared to liquid petroleum. Nothing like being burned by fire you can't see.

Given how quickly an explosive shock wave travels through hydrogen, I doubt anyone near the car would be alive long enough to even register a mild temperature increase when the tank blows up.

And how much energy is lost charging batteries? Because there are no native sources for charged Tesla battery packs. You're either using electricity to charge them at your house (with 60% lost in transmission) or charging them closer to the power plant.

It's more efficient to simply use hydrogen.

I don't understand why anyone would be convinced by arguments like this that don't include numbers, when you can make the argument sound equally valid on either side of the debate.

> using electricity to charge them at your house (with 60% lost in transmission)

The overall losses in Germany are 7%. [1]

> It's more efficient to simply use hydrogen.

Only if you fake your numbers by an order of magnitude, see above.

> I don't understand why anyone would be convinced by arguments like this that don't include numbers.

Still better than your astroturf numbers. If hydrogen is better, so be it. However, the Tesla S can go 450km with one charge today and it can be charged everywhere.

An electric car is the nightmare of traditional car manufacturers: an electric motor costs nothing and lasts unlimited kilometers. You need no engine oil change, the brakes last a lot longer and cars will easily last 1.000.000 miles / kilometers and a lot more with little maintenance. You do need to change the battery but this is not money for the car manufacturer.

So there are two huge industries for which e-cars are a nightmare: petrol and classic car manufacturers.

Disclosure: I drive an MiEV an it works amazingly well.

[1] http://de.wikipedia.org/wiki/%C3%9Cbertragungsverlust (german)

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

That pumped water requires a lot of space up there, so viable spots are fairly limited. It also is fairly difficult to transport compared to hydrogen.

If we're talking about the US, we have tons of open space. Really, tons. Americans don't appreciate just how much open space is in this country. If it's really a concern, it can be done with water towers rather than a conveniently-placed hill.

As for transport, that's what a power grid is for. Transporting hydrogen loses more efficiency than transmission losses.

Batteries are way ahead on every objective measure, and getting better every year.

Um have you seen a pumped storage power plants they are major civil engineering constructions.

You could probably add a small hydrogen storage facility to every wind farm in the UK for less than the cost of the public inquiry into a new pumped storage scheme.

I'm afraid the physics just don't work out for Hydro.

See the Hydro section of Sustainable Energy - without the hot air by David JC MacKay:

http://www.withouthotair.com/c8/page_55.shtml

Even though the land mass of the US is larger than the UK, it's hard to see hydro being more than MacKay's 2kW per day per person...

That's two 40W light bulbs left on all day.

That's not the same thing. In a standard hydroelectric dam, you need an existing river to create electricity.

The goal of pumped storage isn't to create new electricity, but to store large amounts of unused baseload power. This can be done with a standard hydroelectric dam by pumping the water back up into the lake behind the dam, but it can also be an entirely artificial reservoir.

yes but the number of places that are suitable are limited and it might be politicaly sensitive eg flooding Wales and Scotland to provide power for the English.

And farmers might object to you taking the water they use for irrigation

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.

If he thought hydrogen was viable, he'd be working on it.

He is one person, and he is not all knowing. He has limited time and potential. He also has a significant ego and financial interest in their current course.

He's a smart guy, but I'm not going to write something off because he isn't into 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).

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