[EVDL] Hydrogen? What connector is this?

Jim L wrote:
> As to the fuel cell? $750,000 is what the car is estimated to cost at the
> moment. Range? About a 100 miles. Fuel cell loses about 20% of its capacity
> per year.
>
Loses 20% per year? I definitely believe it. I'd love to have a source
for that...
> I did some checking and found that using electricity to create hydrogen and
> then using a fuel cell to create electricity, yields about 50% of the
> original electricity.
>
> Does anybody have an approx energy efficiency for charging batteries. For
> every WATT-HOUR(happy?) that your put in when charging, what is ultimately
> available for running the car?
>
Energy efficiency depends on how often you equalize (if such a battery
chemistry requires it), the depth of discharge (DoD), and the speed of
charge/discharge. Coulombic efficiency for various batteries: (according
to Paul Compton in an earlier EVDL e-mail see:
http://www.mail-archive.com/[email protected]/msg07941.html)

>Lead acid (AGM) up to 90%
>Lithium (Thundersky) 100%
>NiCad 71%
>NiMh 66%

He also added:

>The energy efficiency for a 100Ah Thundersky cell (cobalt chemistry) has
>been measured at 84% (100A discharge and charge)

While there is a lot of factors that affect energy efficiency for each
chemistry, you'll have a good start by guessing 85% of the coulombic
efficiency, so roughly:
Lead-Acid: 70%-80%
NiCd: 60% (I'm not sure I believe this number or the above one; I think
it should be higher)
NiMh: 56%

> Since the range is not all that much greater than an all electric car,
> wouldn't it make more sense to just go all electric?
>
Yes.

Cory Cross

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Jim L wrote:
> Reading this post reminded me of the hydrogen issue. What do you guys
> think about this issue. I ask because our Premier(think Governor)
> just went all gaga with Arnold(California) about a hydrogen highway
> up and down the west coast.

We're veering dangerously close to politics, what with the President and
the Governator coming out enthusiastically for hydrogen. On the
political side, I'll merely point out that the President promising a
hydrogen future when gas went expensive is the same one who shut down a
lot of government biofuel research when he took office.

[ I am not making a partisan point here; rather that politicians of any
stripe will usually make big promises which may have nothing to do with
their actions or realistic options, but which play well to the voters. ]

> I did some checking and found that using electricity to create
> hydrogen and then using a fuel cell to create electricity, yields
> about 50% of the original electricity.
>
> Does anybody have an approx energy efficiency for charging batteries.
> For every WATT-HOUR(happy?) that your put in when charging, what is
> ultimately available for running the car?
>
> Since the range is not all that much greater than an all electric
> car, wouldn't it make more sense to just go all electric?

I don't know the efficiency, but I've no doubt it is cheaper than
hydrogen, especially when you consider the distribution issue:

1) "gas" stations don't currently exist, but must be built; electricity
already comes to your home for "local" recharging. (biodiesel and
ethanol could reuse the existing tanks and pumps, by contrast)

2) The distribution mechanism has much larger implications. Compare the
DOT regulations regarding distribution of class 2 (flammable gas, which
covers hydrogen) hazardous materials and those for class 3 (flammable
liquid like gas):

Class 2: http://tinyurl.com/37ocfk

Class 3: http://tinyurl.com/2ttv6g

Doesn't it seem like transporting a tractor trailer of hydrogen to a
major city, especially one like Baltimore or Boston which has a large
tunnel, will be a problem? Hazmat trucks get routed around Boston's 128
beltway as it is.

3) Given the safety standards around handling gas cannisters, I can only
presume that 'hydrogen' tanks are going to be a larger issue than 'gas'
tanks are today. I sure am not comfortable with rapid dispersal of
pressurized hydrogen in an accident where sparks are likely (I believe
the military calls such a thing FAE, or Fuel-Air-Explosives. Gas leaks,
gas burns, but as long as NBC isn't around it rarely explodes.

4) Both electric and hydrogen cars place more load on the electric
infrastructure, which is already stressed as we saw in California a few
years back. We'll probably need extensive investment into solar or
nuclear power (not likely, but that's off topic too)

So why is Hydrogen such a popular idea? Because it sounds sexy. It
sounds future. It looks shiny. It seems so clean, because the citizen
only sees the water coming out of the fuel cell.

The problem is, it just doesn't make sense. It's a boondoggle.




(Veering temporarily back to the issue of the politics of the possible,
the advancement of biofuels is endangered - in my opinion - by the
historic closeness of corn and the Capital. Corn is such a large part
of American agriculture, and every 5 years the government creates a new
farm bill to ensure that the farmers don't all go broke. But farm is
such an inefficient source for ethanol. We should be using that farm
bill to encourage migration to crops with a higher fuel value, but that
would rock the boat... so don't hold your breath.)

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