Are Fuel Cells a Viable Alternative to Batteries Given Their Challenges?

[signerror]

I'll stop kicking the sod, and get to the main issue. What's the price of a fuel cell? Without a answer to this, the rest is window dressing.

You're missing the discussion. I'm not advocating fuel cells. Neither is Ivan. We are advocating hydrogen combustion engines, taking a hit in efficiency in exchange for vastly reduced cost. The BMW I've been showing pictures of, it has a combustion engine. No fuel cells.

http://www.wired.com/news/images/full/hydrogenbmw4_f.jpg

"12-cylinder, 6.0-liter engine"

Hydrogen produced on site, in the US means that nominally, 40 percent is from burning coal, with a site delivery efficiency of about 36%. But coal is bountiful and cheap. It costs only 100 bucks a ton. It's the reason we can sit a a desk and argue about hydrogen and wring our hands over global warming.

I think the whole point of this thread is we're talking about replacements for petroleum-burning cars, exactly because of climate change. There is no point to EVs, or hydrogen cars, if their energy source is simply another carbon fuel. In my example, I am suggesting we use nuclear power to produce hydrogen, directly splitting water with heat (thermochemistry). Someone else suggested hydrogen from algae, and yet someone else solar thermolysis of water (far earlier in this thread).

 

[mheslep]

...Like Ivan in this thread, I think hydrogen combustion engines make much more sense. These are far cheaper than fuel cells. The BMW has 256 HP on hydrogen.

Agreed, for the near future, though H2 combustion with H2 infrastructure is still not cost effective when compared to a gas/electric plugin hybrid. H2 from ethanol might fly.

 

[mgb_phys]

The advantage of H2 for cars is that you can convert existing cars relatively easily (although not as easily as LPG).
The infrastructure costs depend on where the power is coming from, if you have solar power in Nevada and electric cars in LA then running power cables makes sense. If you have a solar plant in Saudi Arabia then shipping H2 is a lot easier than running a transmission line across the Atlantic.

H2 fuel cells are looking useful in marine applications where you are surrounded by water and space isn't a big problem.
Modern ships, especially cruise ships, use electrically driven pod motors with power generated from diesel and/or gas-turbine engines. There are restrictions on the stack emissions in harbour - fuel cells allow them to supply power for maneuvering and for onboard use without running the engines.

 

[mheslep]

...

How much does a fuel cell cost capable of putting out 100 HP? Not tomorrow's price. Today's...

The fuel cell need only provide average power - 20-30HP. Batteries/Capacitors can provide the peak power (and do in the demo FC vehicles).

 

[mheslep]

...

It's not physically impossible, but for practice it seems far inferior to hydrogen power.

<shrug> The reality is hybrid plugin electric - gasoline vehicles will go into medium scale production in the next few years from several mfns. H2 vehicles, either combustion or fuel cell, will not.

 

[mheslep]

I'll stop kicking the sod, and get to the main issue. What's the price of a fuel cell? Without a answer to this, the rest is window dressing.

...The committee observes that the federal government has been active in fuel cell research for roughly 40 years, while proton exchange membrane (PEM) fuel cells applied to hydrogen vehicle systems are a relatively recent development (as of the late 1980s). In spite of substantial R&D spending by the DOE and industry, costs are still a factor of 10 to 20 times too expensive, these fuel cells are short of required durability, and their energy efficiency is still too low for light-duty-vehicle applications. Accordingly, the challenges of developing PEM fuel cells for automotive applications are large, and the solutions to overcoming these challenges are uncertain.

The committee estimates that the fuel cell system, including on-board storage of hydrogen, will have to decrease in cost to less than $100 per kilowatt (kW)4 before fuel cell vehicles (FCVs) become a plausible commercial option, and that it will take at least a decade for this to happen.

http://www.nap.edu/openbook.php?record_id=10922&page=4
One to two years ago this was $1000 to $2000 per a PEM fuel cell kw, low qty. Solid oxide FCs offer a substantial reduction in cost.

Edit: In testimony before Congress, NREL used this study: http://www.nrel.gov/hydrogen/pdfs/39104.pdf" , which estimates ~$100/kw in 500k qty are possible, with platinum in the electrodes being the #1 cost driver. That compares to $30/kw for an ICE, noting that an ICE vehicle needs a lot more ancillaries.

 

[mgb_phys]

<shrug> The reality is hybrid plugin electric - gasoline vehicles will go into medium scale production in the next few years from several mfns.

Which is probably the worst of all worlds. With the possible exception of delivery vehicles and taxis operating in downtown where you care about pollution more than economy, hybrids don't make sense from a fuel economy/environmental/life time standpoint.
A 80mpg VW with a 1.2L diesel engine is better than a 35mpg Prius.

The reason for building hybrids is that you can stick a second battery and a slightly upgraded starter motor in your existing model and suddenly you are green.
Like the Ford F150 or the Merc S-class hybrid, 300hp gasoline engines with a 20hp 'hybrid' mode.

 

[mheslep]

Which is probably the worst of all worlds. With the possible exception of delivery vehicles and taxis operating in downtown where you care about pollution more than economy, hybrids don't make sense from a fuel economy/environmental/life time standpoint.
A 80mpg VW with a 1.2L diesel engine is better than a 35mpg Prius...

Pollution from a PHEV in EV mode (ie commuter) is zero at the vehicle.

That 80mpg VW is a small 50hp two seater. The Prius is a >100hp (ICE+electric motor) 4 seater/hatchback. Payback for non-plugin prices varies - some as low as a year, some never. The Prius is not a PHEV. PLUGIN hybrids can make a lot of sense, depending on the battery price and the cost of gasoline.

 

[mgb_phys]

What do you mean by a 'hybrid plugin electric'?

Gasoline hybrids are mostly a marketing invention to continue selling large cars as 'green'. Yes the VW is smaller - that's the point. But it's still a four seater 2 door hatchback, it's about the size of the original Golf(Rabbit).

Plugin electric vehicles will be great one day (hopefully soon) when people (on a certain continent) realize that they don't need a 2ton High Mobility Multipurpose Wheeled Vehicle to take a 5year old to school.

 

[mheslep]

What do you mean by a 'hybrid plugin electric'?

As I said - hybrid plugin electric - gasoline. http://en.wikipedia.org/wiki/Plug-in_hybrid

Gasoline hybrids are mostly a marketing invention to continue selling large cars as 'green'. Yes the VW is smaller - that's the point. But it's still a four seater 2 door hatchback, it's about the size of the original Golf(Rabbit).

Fine if you want small, just don't compare to it substantially more powerful and larger vehicle when citing mpg.

 

[Phrak]

The target moves but the game stays the same.