A GM fuel cell vehicle parked at Pep Boys?

[wtmusic]

Imagine my surprise when I pulled into Pep Boys the other day and saw an honest-to-goodness GM Equinox FCV parked in the lot:



The store wasn't crowded so I easily located a guy who looked like he might be the owner (OK, the GM polo shirt helped) and got these stats out of him:

Range: 175-200 miles
Fuel: compressed hydrogen (900 bar)
Availability: 2010 earliest; fleets only

Pretty sure he worked at the GM service center a few blocks away, which is the infamous one featured in "Who Killed the Electric Car?" where the last remaining EV-1s were stored. But what would he be buying at Pep Boys? Turns out it wasn't wiper blades or even a proton-exchange membrane, but a large plastic gasoline can.

Hmm...

[Selatius]

1. What a lot of people seem not to understand is hydrogen is not an energy source.

Merely, it acts like a battery, storing potential energy that can be converted to kinetic energy. The real fuel is used whenever you split hydrogen from oxygen. That process requires electricity, usually generated by fossil fuels.

[wtmusic]

2. A pretty lousy battery, at that

given its volatility and low energy density.

But you're absolutely right. I would have pinned him down but he was gracious enough to talk to me. And actually I feel sorry for GM employees these days. They're stuck with upper management that is destroying the company.

[OKIsItJustMe]

6. Low energy density?

Hydrogen actually has the highest energy density (by mass) of any fuel. The challenge is that hydrogen itself is not very dense under "normal" conditions. So (for example) that plastic gas can would not work well to carry some hydrogen from the station to a stranded car.


Hydrogen has a great advantage over other fuels, in that it is relatively easy for us to produce.

Given a supply of electricity and water, you can generate hydrogen, and actually do it fairly efficiently.
http://en.wikipedia.org/wiki/Electrolysis
http://technologyreview.com/Biztech/16523/

Hydrogen can be produced biologically as well, and (it seems) more efficiently than ethanol can:
http://www.nsf.gov/news/news_summ.jsp?cntn_id=110648

[wtmusic]

24. No.

Liquid hydrogen has 1/4 the energy by volume as gasoline (there is more hydrogen in 1 gallon of gasoline than there is in 1 gallon of liquid hydrogen).

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

You GM guys crack me up.

[OKIsItJustMe]

30. Yes

Read what I wrote:
http://www.democraticunderground.com/discuss/duboard.php?az=show_mesg&forum=115&topic_id=137390&mesg_id=137405

... Hydrogen actually has the highest energy density (by mass) of any fuel. ...

Read what the Wikipedia entry you referenced says:
http://en.wikipedia.org/wiki/Energy_density

... (Hydrogen has a higher energy density per unit mass than does gasoline, but a much lower energy density per unit volume in most applications.) ...

http://hypertextbook.com/facts/2005/MichelleFung.shtml


BTW: What's a "GM guy?"

[wtmusic]

32. Volume is the relevant issue

There simply isn't enough room for hydrogen, in a passenger car, to provide adequate range and/or power.

[kestrel91316]

3. Gasoline is also not an energy "source". It is merely a storage

medium for solar energy that arrived on Planet Earth millions of years ago.

You're gonna have to find a better complaint against hydrogen........

Energy can be neither created nor destroyed. All matter is mere energy storage.

[wtmusic]

4. Yes, but here's the difference:

The energy stored in gasoline is returning CO2 to the air which was sequestered while millions of species of plant/animal life evolved...we're now liberating that CO2, warming the planet, and rendering those species extinct.

[OKIsItJustMe]

8. An excellent argument for the superiority of hydrogen!

Here's another difference.

We can't "make" gasoline nearly as easily as we can "make" hydrogen.

[wtmusic]

26. Both are bad news.

We don't need to make either. Let's generate eletricity from LNG and use it to power electric cars, which don't require new infrastructure, expensive repairs, and generate a fraction of the CO2.

[OKIsItJustMe]

28. I don't understand your point here

Using LNG to generate electricity to run electric cars would create less CO₂ than is being created today. Of course, LNG is in limited supply, and we don't have a fleet of electric cars.

I'd love to see a fleet of electric cars, but that won't happen for several years.

We have a fleet of internal combustion engine (ICE) powered cars, which can be converted relatively easily to run on hydrogen instead of (or in addition to) gasoline.

It would take a significant investment to do the conversion; but it's a lot less expensive than buying a new electric car (even if they were available in the quantities required, which they aren't) or converting a current ICE car to be an EV.

As you point out, the same infrastructure could be used.

[wtmusic]

33. Electric cars aren't available because GM doesn't want them to be.

If you haven't seen "Who Killed the Electric Car?" you need to.

We have a fleet of internal combustion engine (ICE) powered cars, which can be converted relatively easily to run on hydrogen instead of (or in addition to) gasoline.

Converted relatively easily? FCVs cost about a million dollars, aren't durable, and have no place to fill up. A minimal (10,000 stations) hydrogen infrastructure will cost half a trillion dollars. Who's gonna pay for it?

Viable electric cars have been ready for 7 years now. They require almost no service and no gasoline. That's why they aren't available.

[kestrel91316]

13. Preaching to the converted here........I know the evils of CO2, lol.

We should be eagerly switching to hydrogen and any other compact energy storage media which can be utilized without doing as much harm as burning fossil fuels does. Which is why I truly don't "get" the beef with hydrogen.

Can't hydrogen be produced with electricity from SOLAR power, lol???

[wtmusic]

27. Hydrogen is anything but compact

There are two huge tanks under the Equinox which run the length of the car, pressurized to 900 bar (if one explodes, think IED). With both tanks full the car can go 200 miles max.

Just making hydrogen requires fossil fuels, unless you use renewables to create electricity and electrolyze water that way.

Or, you can just lose the messy hydrogen step (which reduces it's efficiency by roughly 50%) and transmit that energy through the grid to clean, efficient electric cars.

[OKIsItJustMe]

29. There are better ways to store hydrogen

http://www.democraticunderground.com/discuss/duboard.php?az=show_mesg&forum=115&topic_id=137390&mesg_id=137407

[wtmusic]

34. Better?

"Issues with complex metal hydrides include low hydrogen capacity".

"For this system, the following reversible displacive reaction takes place at 285°C and 1 atm...In this reaction, 6.5 wt.% hydrogen can be reversibly stored, with potential for 10 wt.%"

Low hydrogen capacity? 285°C? Explain to me how that's going to work. :eyes:

[phantom power]

5. Here's my complaint against hydrogen:

1) it's a very small molecule, and you need special hardware to handle it.

2) it's a very reactive molecule. that's another reason you need special hardware to handle it.

3) it's energy density per unit mass is high, but it's energy density per unit volume is low. to compensate, it has to be stored at high pressure. Yet again, this requires special hardware, and it's hard to keep the weight and size down for an application like an automobile.

There is no reason we need to solve these problems. If you can manufacture H2, you can manufacture methane. Or DME. Or butane. Or propane. All of those are easier to handle, with standard hardware, and they don't require storage at extremely high pressure to work well in an automobile.

[OKIsItJustMe]

7. Actually, hydrogen doesn't need to be stored at high pressure

http://www1.eere.energy.gov/hydrogenandfuelcells/storage/metal_hydrides.html

Watch part 1:
http://www.pbs.org/saf/1506/video/watchonline.htm


Metal hydrides are a much safer way to store (relatively) large amounts of hydrogen.

[TreasonousBastard]

9. Back in the 80s Mercedes built a bus with...

hydride hydrogen storage. 'Twas a Scientific American about it back then.

Its primary power was a hydrogen turbine but it had a huge flywheel to absorb braking energy and assist acceleration. Lots of other neat stuff in it, and storing the hydrogen at low pressure created heat, which was later used to release the stored hydrogen when needed.

[phantom power]

10. Yeah, but why?

What's the payoff over just using NG, propane and friends?

[OKIsItJustMe]

11. Because hydrogen is really, really easy to generate renewably

The same cannot be said for NG, propane and friends.

[phantom power]

12. Use the H2 as feedstock for making methane (et. al.)

Don't waste effort figuring out ways to get H2 from the factory, through a distribution system, into an automobile. It's just not a problem that needs solving.

[OKIsItJustMe]

15. No need to distribute to cars

Anywhere you have electricity and water (say... that little gas station on the corner) you can generate hydrogen.

[OKIsItJustMe]

18. Methane etc. may have their uses

For example, as an interim replacement for the "natural gas" currently used in stoves, furnaces etc.

However, burning it will inevitably produce CO_x, which is one of the things we're trying to avoid doing.

[NickB79]

20. If you use atmospheric CO2 to react with H2, the result would be carbon-neutral

When the methane is then burned.

Of course, at this point we need to become carbon-negative to stand a chance in hell of surviving, so just being carbon-neutral probably isn't enough.

[wtmusic]

25. Even lower energy density

We're going backward here.

[kestrel91316]

14. Methane "manufacture" is easy: feed kestrel beans.

[OKIsItJustMe]

16. That won't work at an industrial level

Kestrel doesn't produce pure enough methane.
http://en.wikipedia.org/wiki/Flatulence
http://www.smellypoop.com/facts_on_farts.php

[kestrel91316]

17. Some days it sure would........

[NickB79]

21. Maybe add some hard-boiled eggs for "high-octane" gas

Or maybe that's just my particular curse.

[kestrel91316]

22. Cabbage, my friend. Cabbage.

[phantom power]

23. I once thought I was actually dying. It turned out to be teh cabbage.

I had no idea gas could hurt so much.

[tinrobot]

19. True, but is it easier to charge a battery or fill a tank?

That may be the overriding factor as to whether hydrogen wins out over batteries.

Both are similar in that they are storage mediums for electrical energy, but how that energy is stored and transported is very different.

[NickB79]

36. The fork-lifts we use at work simply swap out batteries

A huge lead-acid pack slides in and out in under 5 minutes with a special grappler.

I could see something similar in a battery-powered car: every time you stop to recharge, you just replace the battery and go.

[wtmusic]

37. Interesting.

Standard battery pack. Kinda like swapping out a LNG barbecue canister.

And when Li-Ion packs are available you wouldn't even need the grappler.

[tinrobot]

38. But with each battery pack worth thousands of dollars...

...it would be a very enticing target for thieves.

I'd imagine security concerns could make a battery swap less than trivial.

[ejbrush]

31. 900 bar?!?

Holy crap, that's around 13,000 psi. I truely want a renewable future, but I don't want to be anywhere around that bastard in the event of an accident or fire. WOW!

[wtmusic]

35. No kidding. Ka-boom. nt