Fueling the future: Fuel cells show promise

[OKIsItJustMe]

http://www.signonsandiego.com/news/2010/mar/07/fueling-the-future/

Fueling the future: Fuel cells show promise

Uses seen for more efficient power generation; companies hope to work out bugs

By Onell R. Soto, UNION-TRIBUNE STAFF WRITER

Sunday, March 7, 2010 at 12:04 a.m.

Fuel cells, which decades ago powered the moon mission, are quietly making their way into businesses and homes, and some see them as the future of power production.

Instead of burning fuel to make heat that then drives a turbine, fuel cells use an electrochemical reaction similar to that inside a battery to make electricity.

Proponents say today’s fuel cells produce more power from the same amount of fuel than the most efficient gas turbine, create fewer pollutants and give off heat that can prove useful.

“There isn’t another technology that can do this, produce power at this high efficiency at this low emissions at that small a scale,” said fuel-cell researcher Jack Brouwer.

...

[yourout]

1. A couple of questions....How much energy is wasted in making the Hydrogen and

is there a methodology of measuring the ratio of energy input to useful energy?

[OKIsItJustMe]

2. Of course there is a methodology for measuring EROEI

That's fairly straight-forward.

[yourout]

3. Any idea were these fuel cells fall as far as EROEI?

What is the EROEI of current fuel sources?

[OKIsItJustMe]

4. This is not about any specific fuel cell

(You may want to read the article.)

[FreakinDJ]

5. Its only in vehicals where they suck because of the weight

Power/Weight ratio is every thing in a car - but not a house

[OKIsItJustMe]

6. They're lighter than batteries in vehicles

Did you ever wonder why NASA used fuel cells rather than batteries starting with Gemini 5?
http://www.nasa.gov/centers/glenn/technology/fuel_cells.html

...

Alkaline fuel cells have been the primary source of electrical power on human spaceflight systems for over four decades. However, alkaline fuel cells use a costly, aging technology. Much work must still be done before improved fuel cells can be used in spacecraft, which operate at extreme altitudes and low temperatures for extended durations. This technology will enable new space exploration missions as well as fuel savings, quiet operation, and reduced emissions for aircraft.

Glenn is investigating three types of fuel cells: proton-exchange-membrane fuel cells (PEMFCs), regenerative fuel cell (RFC) systems, and solid-oxide fuel cells (SOFCs). NASA first developed PEMFCs for the Gemini mission, but because PEMFCs had water-management problems, alkaline fuel cells were used through the 1990s. Improved PEMFCs promise to be more powerful, lighter, safer, simpler to operate, and more reliable. They will last longer, perform better, and may cost much less than current alkaline fuel cells. PEMFCs use hydrogen fuel and produce only water--so pure that NASA plans to use it as drinking water for spacecraft crews. NASA PEMFCs may also produce electricity for spacesuits, airplanes, uninhabited air vehicles, and reusable launch vehicles.

In RFC systems, fuel cells use hydrogen and oxygen to produce electricity, water, and heat. Then a solar - powered electrolyzer breaks the water into hydrogen and oxygen so that the fuel cell can use it again. The waste heat is also used. RFC systems provide efficient, environmentally friendly, highly reliable, renewable energy conversion. Glenn researchers have developed RFC concepts for storing energy on the International Space Station, high-altitude balloons, and high-altitude aircraft. They are now investigating RFCs for storing energy on the Moon or Mars.

SOFCs are being considered for power generation and for use in space because of their high efficiency, high power density, and extremely low pollution. They have an all-solid construction and can operate at high temperatures--producing clean, efficient power from easy-to-transport fuels instead of pure hydrogen. SOFCs also are being developed for portable electronic devices, cars, and aircraft.

...

[FreakinDJ]

7. And how many batteries per mile in an electric car

Tesla - the only real electric car right now uses Lithium Batteries for a reason

[OKIsItJustMe]

8. Tesla uses batteries right now, because they're cheaper

However, a tank full of hydrogen and a fuel cell will give you greater range, for less mass, and less volume.

Top Gear did a decent review of the Honda Clarity FCX
http://www.topgear.com/uk/videos/honda-clarity

[OKIsItJustMe]

9. NRL's Ion Tiger Sets 26-Hour Flight Endurance Record

http://www.nrl.navy.mil/media/news-releases/126-09r/

NRL's Ion Tiger Sets 26-Hour Flight Endurance Record

11/23/2009 - NRL Press Release 126-09r
Contact: Donna McKinney, [phone]

The Naval Research Laboratory's Ion Tiger, a hydrogen-powered fuel cell unmanned air vehicle (UAV), has flown 26 hours and 1 minute carrying a 5-pound payload, setting another unofficial flight endurance record for a fuel-cell powered flight. The test flight took place on November 16th through 17th.

The electric fuel cell propulsion system onboard the Ion Tiger has the low noise and signature of a battery-powered UAV, while taking advantage of hydrogen, a high-energy fuel. Fuel cells create an electrical current when they convert hydrogen and oxygen into water and heat. The 550 Watt (0.75 horsepower) fuel cell onboard the Ion Tiger has about four times the efficiency of a comparable internal combustion engine and the system provides seven times the energy in the equivalent weight of batteries. The Ion Tiger weighs approximately 37 pounds and carries a 4- to 5-pound payload.

The Ion Tiger fuel cell system development team is led by NRL and includes Protonex Technology Corporation, HyperComp Engineering, and Arcturus UAV. The program is sponsored by the Office of Naval Research.

This latest flight test improves on Ion Tiger's previous unofficial flight endurance record of 23 hours and 17 minutes that took place on October 9th and 10th.

NRL has now demonstrated that PEM fuel cell technology can meet or surpass the performance of traditional power systems, providing reliable, quiet operation and extremely high efficiency. Next steps will focus on increasing the power of the fuel cell to 1.5 kW, or 2 HP, to enable tactical flights and extending flight times to 3 days while powering tactical payloads.

For more information about Ion Tiger:
http://www.navy.mil/swf/mmu/mmplyr.asp?id=13236">All Hands Television - Hydrogen Fuel Cells

http://www.onr.navy.mil/Media-Center/Press-Releases/2009/Surveillance-Vehicles-Alternative-Energy.aspx">Office of Naval Research - "Surveillance Vehicles Take Flight Using Alternative Energy"

[Statistical]

14. No they aren't.

Tesla uses batteries because right now Fuel Cells are prohibitively expensive.
The battery back in the roadster is massive. It weighs nearly a thousand pounds to provide only 53 kWh

Hydrogen energy density is 1.6 MJ per kg.

The best (non commercial) lithium ion batteries only 0.72 MJ per kg which is less than half that.

Finding the power density of tesla roadster battery pack is easy.
The battery pack in the roadster is 53kWh and weights 450kg. 3.6 MJ = 1 kWh
53*3.6/450 = 0.42 MJ per kg.

Roughly one quarter the power density that Hydrogen has.

[OKIsItJustMe]

17. Check out the "Top Gear" review of the Tesla

http://www.youtube.com/watch?v=8DfHyGD7_pM

[kristopher]

10. The trouble with fuel cells is overall system efficiency

This article explains the problem.
http://www.physorg.com/news85074285.html

And here is a graph laying it out visually. The ratio of the final number indicates how much non-carbon infrastructure (solar, wind etc) we'd need to build for each system. So in the best case represented by this generalized analysis, the 23/69 (or 1/3) means we'd need 3X the number of solar panels or wind turbines to power an auto with an H2 system than we would with lithium battery storage.

[OKIsItJustMe]

11. Can we finally retire that chart?

http://www.democraticunderground.com/discuss/duboard.php?az=show_mesg&forum=115&topic_id=234625&mesg_id=234625

[kristopher]

12. No.

When there is a legitimate proven technology that changes the final ratio to favor fuel cells then it would become obsolete, however your continued hopes for fuel cells are dashed by the efficiency of fuel cells themselves. That next to final step is a dilly.

[OKIsItJustMe]

13. Time for a new chart

This chart assumes that we want to drive our cars using the Sun.

I've given some advantages to the BEV. (I'm not charging a penalty for charging/discharging a battery. I'm not charging a penalty for transmission, or AC/DC conversion. I'm assuming 20% efficient PV's)

On the FCEV, I'm not charging a transportation penalty. (It can all be done at home, using something akin to Honda's "http://automobiles.honda.com/fcx-clarity/home-energy-station.aspx">Home Energy Station" or at a commercial filling station. In either case, hydrogen can be generated on site.)

Start with 100 W of solar, which translates to:

[kristopher]

15. Nice try, no cigar... That is an apples to oranges comparison

The problem with the low efficiency of the fuel cell process is the extra generating infrastructure required. Since the Lh2 process is experimental we don't know the cost or practicality of its use. Does the experimental 'light > h2' (xLh2?) reduce the amount of infrastructure needed compared to batteries?

The answer is no, it doesn't. The proper comparison would be:
xLh2 = 100w > liquifaction = 85w > FC = 42.5w > vehicle = 38.25w

PV = 100w > battery charge/discharge = 95 > vehicle = 85.5w


You are conflating two areas of concern - cost of PV vs the xLh2 process, and the efficiency of the processes.

Now, if you can show that the xLh2 process can produce 100w of electricity for less than a PV can produce about 220w, then you have a case to make.

The only other advantage the xLh2 process MIGHT offer is space, but not knowing what it actually required for the system, it would be premature to make that conclusion.

[OKIsItJustMe]

16. Fuel cells have inherent advantages over batteries

I've asked you before.

Why did NASA decide to use fuel cells instead of batteries?

[kristopher]

18. Why are all automakers planning production of PHEVs and BeVs?

The drawbacks to a hydrogen infrastructure a severe.

[Statistical]

19. Cost.

Batteries are roughly 1/5th the cost of equivelent fuel cell & hydrogen tank.

As it is EV have a cost premium. Currently the market won't accept a $150K Honda Accord Fuel Cell vs a $30K Honda Accord Internal Combustion Engine.

[kristopher]

21. And policy related to infrastructure

We have an existing grid. Building another distribution infrastructure from scratch doesn't make sense; especially one with the problems associated with H2.

[Statistical]

24. Why an new grid?

H2 can be produced on-site at the point of fueling the vehicle.

[OKIsItJustMe]

20. Evasion

Why did NASA use fuel cells rather than batteries?

[kristopher]

22. If you want to make a point, then make it.

[OKIsItJustMe]

23. I believe you've made it for me.

You refuse to acknowledge the inherent advantages of FCEV's over BEV's.

[kristopher]

27. You are afraid to list the "advantages" because you know they compare poorly to our needs.

List them and we can discuss them. So far, all you ever do is promote hype and "wow that sounds cool" type of information.

As I've previously stated, fuel cells may have a valid place in applications where the energy density of liquid fuels justifies the loss of system efficiency. There was an article posted by fieldmouse about methane from waste being used for city buses, that seems tailor made for fuel cells. But if you give a shit about trying to meet our climate change needs, you really need to stop trying to make them into something they are not.

[OKIsItJustMe]

28. I've listed them in the past (even in this thread)

You're afraid to.

[kristopher]

29. Feel free to clarify the list of benefits you see.

The only thing I see above is the claim that fuel cells weigh less. If that's the "list"...

[OKIsItJustMe]

30. Why do you think NASA chose to use them?

It's a simple question.

Why do you suppose the military is developing drones that use fuel cells (rather than batteries?)

[kristopher]

31. If you want to make a point, then make it.

[bananas]

32. Probably weight.

Weight is a prime consideration for rockets and planes. For manned missions, the fuel cells also output potable water as well as electricity and heat, so it kills three birds with one stone. For drones, they also get lighter as they burn fuel, increasing distance.
http://en.wikipedia.org/wiki/Energy_density

[diane in sf]

25. They are energy storage...

[Odin2005]

26. Hydrogen is a SCAM. Batteries and algal biofuel is the future.