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Comment by reitzensteinm | Hacker News Reader

While it didn't directly involve Tesla, what got me about that episode was the claim that battery cars are totally irrelevent because of 'hydrogen power'.

They point out that the power for electric batteries has to come from somewhere, and completely gloss over that for hydrogen.

Why they didn't go all the way and advocate fusion powered cars is beyond me.

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> Why they didn't go all the way and advocate fusion powered cars is beyond me.

Isn't that what the hydrogen is for? <g>

Hydrogen is not an energy source, but a means by which to store energy. You know, like a battery.

Exactly my point. I've put hydrogen power in quotes in case that was unclear.

Like oil stores energy from the sun.

Energy can't be created or destroyed, just transformed from one form to another. So nothing is really an energy source. I'd say "energy source" is the vernacular for stored energy, in terms of where humans source their energy for machinery, electricity, etc.

While you are technically correct, that's not the best model for this. Energy in oil is ultimately stored energy from the sun. But for hydrogen powered cars, we must take one stored form of energy (e.g. fossil, nuclear) and use it to make the hydrogen. Or skip the oil step and use solar.

So question is, are we storing new energy, or converting previously-stored energy to a different format? The latter is an externality as obviously oil, uranium etc were around long before humans.

It is both. You can use it in a fuel cell form whereby you keep the water produced from its combustion, run electricity through it and get oxygen and hydrogen back. Alternatively though, the way hydrogen is turned into energy works if you just refill the hydrogen and throw away the water.

The point about hydrogen is that you can fill up in a traditional manner (quickly), rather than having to charge a battery.

At battery changing stations, empty batteries can be swapped for fully charged ones. That takes about the same time as it would to fill a fuel tank.

http://en.wikipedia.org/wiki/Better_Place

  Israel is the first nation in the world that partnered with Better Place 
  to have an all-electric car infrastructure. Shai Agassi believes that 
  in Israel by 2016, plus or minus a year, more than 50% of cars sold will 
  be electric and that by 2020, Israel will achieve oil independence. 
  The Baran Group signed an agreement with Better Place to build 
  51 battery switch stations over the course of 2011 to cover all of Israel.

Meta-comment:

Please don't post quotes using pre-formatted text. It forces the browser to use the full width. That, in turn, puts a horizontal scrollbar on my browser, so I have to scroll back-and-forth to read any of the comments.

I find it works much better to quote using asterisks. (We could also lobby pg for a BLOCKQUOTE feature)

That's a brilliant solution to the problem for cars that aren't Teslas, which has something like 1800 batteries lining its cabin floor. I don't think they'd be easily swapped.

For cars that don't implement batteries this way, I'm wondering how they allow for non-floor-mounted installations preventing the batteries from destroying their handling.

Further, how are the filling stations expected to deal with the variety of non-standard battery types on the market?

you can make hydrogen via other means, directly from sunlight, for example, although admittedly that technology is not here yet.

you mean the technology where you connect electrodes to solar panel or wind turbine, put them into water and hydrogen and oxygen come out?

The energy has to come from somewhere, but it doesn't have to come from electricity (every conversion means energy is lost, and a light -> electricity -> water conversion is potentially less efficient than a more direct conversion).

Hydrosol-2 (see http://en.wikipedia.org/wiki/Hydrosol-2) is an example of solar hydrogen production with no electric current intermediate - it involves high temperatures, so I'm not sure how much energy is lost maintaining that temperature compared to captured producing hydrogen, but it could theoretically be more efficient.

His point was Hydrogen was just another form of battery.

Like Oil.

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