Hydrogen Power

[CCycle]

Just read the latest issue of Popular Science (Jan 05).
They have a very good article debunking hydrogen power pg 63.
They explain nine reasons hydrogen power will not fly in autos.
Could it be that the world is finally catching on to what we engineers knew all along?

 

[patprimmer]

I personally see ethanol as the easiest transformation, once fossil fuels become so expensive that ethanol makes sense.

Ethanol conversions will need a fuel system upgrade to accommodate the different A:F ratio, and to overcome corrosion and seal compatibility issues.

Waste product from food crops could be used, and I expect food crop production will be diverted.

Farmers will support it because it will give them an extra market, and farmers seem to have disproportionately high political clout.

Potentially the car will have more performance and better thermal efficiency if the higher octane rating is fully utilised.

The range will be reduced due to the lower A:F ratio.

The best benefits will come from new cars designed with the fuel in mind from the start, but retrofit conversions will be viable once the cost incentive is there.

Regards
pat pprimmer@acay.com.au
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[shbazjinkens]

Actually Bio-diesel (vegetable oil product) can be used without modification in diesel engines. I could see it taking over rather than ethanol, or perhaps with ethanol. I believe that some fuel lines are vulnerable and engines which have used diesel for some time will see dirty oil as the grime is washed away with the biodiesel, but otherwise it's freely interchangeable.

Some manufacturers have claimed that gummy deposits will form on injectors and other fuel system components, but the biodiesel homebrewing communities tend to object with pictorial evidence. I would suspect that it can happen, but only with improper biodiesel.

The most interesting argument for biodiesel that I've read yet comes from the UNH Biodiesel Group. They want to use desert land to grow algae, and it is a rather sensible plan really. An interesting read if you have the time.

One problem is that I've read biodiesel production has an efficiency of under 80%. I'm not sure how the algae production would fare, as that percentage is probably for seeds or soybeans.

 

[JayMaechtlen]

bio-anything (ethanol, algae, whatever) requires energy (solar or lamps) plus water (normally non-saline) plus physical space (land area or hydroponics) plus raw materials. (well, CO2 and N2 are in the air, but still need minerals, etc.)
Bio-anything also tends to be hydrocarbon, which means that the CO2-concerned folks might not be happy with it.
Anything "renewable" means "use existing energy flow better" which means, in the end analysis, solar, ocean, or geothermal. Nuclear isn't precisely renewable, but effectively unlimited fuel. (close enough).
If we ever get Fusion practical, then- well, we can talk about that in another 10 years and see if it is any closer...

Nuclear may be the only thing that is dense enough to make the energy we need and still leave us the open space we want. Use that energy for de-salinization and electric, make Hydrogen (or whatever) for portable use. (cars, trucks, cross-country freight trains, etc)

Biodiesel seems like a great way to make use of hydrocarbons that would otherwise be disposed of. I hope we look very closely at what is in the fuel and what comes out of the tailpipe, though.

regards
Jay

Jay Maechtlen

 

[patprimmer]

Ethanol can also be made from otherwise waste vegetable matter, It's just to expensive to make fuel that way.

The CO2 in bio fuels comes from the atmosphere and is released back into it. Net change zero.

Regards
pat pprimmer@acay.com.au
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[GregLocock]

"1) Well to wheel efficiencies are no better than what is currently available from a diesel engine

efficiency means nothing when you have a cheap renewable source of energy.

2) No practical method of storage and distribution

10,000 psi tanks, meet all required standards and fail safe, and hold hydrogen at 11.5% wt.
liquid hydrogen, metal hydrides

3) doesn't solve the fundamental problem

fundamanetal problem is not CO2 and water!! it is SOx, NOx, CO, CO2 and PM"

1 Oh really. Where is this /cheap/ renewable source of energy? Trees? An absolute dedication to increasing efficiency is the only way I can see of getting 'green' energy to work.

2 Interesting. Even more interesting is that people in the industry are unaware that the storage issue has been solved. Do you have a credible reference for these tanks? What are the problems associated with them? I don't have any problem with high pressure tanks as such, but 10000 psi is rather higher than anything I've ever dealt with - to put it in context that is FOUR times higher than the PEAK pressure seen in a diesel engine's combustion chamber, and 2.5 times higher than a high pressure hydraulic system. I'm not too sure how to build an efficient (that damn word again) pump that will handle that sort of pressure, and then how do you get the pressure back down to something reasonable without freezing the entire car?

3 Exhaust emissions from modern gasoline engines, with the inevitable exception of CO2 and H20, are a tiny proportion of the pollutants seen in a city. There is no fundamental reason why diesels could not be as clean, it just takes $$$.



Cheers

Greg Locock

 

[tbuelna]

GM produces tens of thousands of flex fuel vehicles every year. They are capable of running on gasoline or E85 (85% ethanol). Biomass derived ethanol is fairly economical to produce and is virtually "carbon neutral". There are currently several hundred filling stations across the U.S. selling E85.

We (in the U.S.) have an environmentally and economically sound transportation fuel solution in place and working. Why do you want to mess with hydrogen and fuel cells?

http://www.e85fuel.com/

http://www.gm.com/automotive/innovations/altfuel/

 

[shbazjinkens]

Biodiesel seems like a great way to make use of hydrocarbons that would otherwise be disposed of. I hope we look very closely at what is in the fuel and what comes out of the tailpipe, though.

Emissions are lots better than petro-diesel with the exception of NOx. I've read that people have reduced the NOx emissions to lower than petro-diesel emissions by adjusting the engine timing. Here is what the EPA has to say about it:

http://www.epa.gov/otaq/models/biodsl.htm

Sulfur and particulate emissions are almost non-existant in comparison to petro-diesel.

I also forgot to note that the energy density is lower. It is still loads better than the energy density of hydrogen, however.

2 Interesting. Even more interesting is that people in the industry are unaware that the storage issue has been solved. Do you have a credible reference for these tanks? What are the problems associated with them?

I've read that one of the associated problems with hydrogen holding tanks is that the metal reacts with the hydrogen to form hydrides, which are brittle and eventually lead to a tanks demise. I'm no chemist so I can't comment on these claims. I'm also told that because the H2 molecules are so small they won't stay in tanks forever. Metal hydride chips are IMO a clunky and heavy replacement for liquid fuels, I'm not sure what the methods for separating the hydrogen from the metal are.

 

[HydroScope]

well of course bio-diesel and ethanol will have a future you would have to be silly not to see that coming.

ethanol blending 10%
bio diesel 20%

both without any mods to cars,

farmers may support it but how do they grow food for billions of people and keep our dependence on liquid fuels at bay? easier to grow food with a few wind turbines on their land too, farmers love that too they get paid and do nothing!! If it wasn't for the farmers a lot of wind turbine projects would be given the flick. what happens in drought and flood and hail storms, the world will for ever be in swinging fuel prices.

higher octane = higher CR be used in car = higher efficiency for spark ignition engine. Diesels already way above this. Performance increase? ? ? ?

the ultimate efficiency winner is a lean burning engine combined with direct injection. Diesel already do this .

future advancement will always come from lighter stronger engine components. and better layout.

1) words taken out of contexts I will expand. . .

efficiency means very little when we develop a cheap renewable source of energy.

for instance Tasmania creates wind power at lower price than all other states in Aust ave. @ $50 MWhr - ABARE 2003

coal power off peak $20-30
peak $150 - 250

the average $80 - 100

Source - Assement of Technological options, A report for the prime Ministers Strategy, Dec 2002

future projected costs of wind power in Tassie is a low $28 MWhr

maybe wind power in the future can be the low cost renewable energy, Tassie very serious about hydrogen power and have post bikes running on hydrogen, joint venture with the university of Tasmania, they have a newly added hydrogen research R&D centre ;O) bike cost to modify $5000 AUD

2) read all about it . . .

http://www.qtww.com/core_competencies/gf_storage.shtml

3)

You are kidding yourself

National database of pollution emissions, department of Environment and Heritage -

http://www.npi.gov.au

2003-2004 emissions

CO 8.7Million kg electrical supply
800M kg motor vehicles


NOx 150M kg electrical supply
120M kg Motor Vehicle

10 mm 5.8M motor Vehicle
3.8M electrical supply

These are N.S.W figures ONLY

And so on and so on for HC, SOx CO2. Etc Etc . . .

You mustn’t live in the city if you did you would see the brown haze, or herd of the unfortunate few that choose to end their life with the exhaust of their car, if pollution was only a small amount neither of these things could happen.

shbazjinkens

You are talking about hydrogen embitterment a major problem back in the 60’s probably as nasa where experimenting with it for their man on moon mission. These days simple heat treating and even more simple avoiding the metals that are susceptible to it. Metals that are often effected by hydrogen embitterment can be heated where the hydrogen will expand out of the intistial spaces of the metal, especially if the hydrogen got in there from welding with moisture around and ultrasonic testing has done wonders for picking up cracks before they break if all the other pre-treatments fail ;o)

 

[GregLocock]

I agree Australia's car fleet is too old and too horrible, emissions wise. Non the less, if you got rid of the old cars and the truck engines your numbers would change significantly. You would get the same improvement in pollutants, just about, whetehr you replace old cars with up to date cars, or hydrogne cars (except for CO)

That tank design does not resolve ANY of the significant issues I raised. It's a piece of carbon fibre with a liner. Big deal.

Wind power is not cheap, for most places in the world.

I did not quote you out of context, I quoted you fully.



Cheers

Greg Locock

 

[tbuelna]

To be a realistic and practical fuel source for transportation, the fuel system must meet some basic requirements: it must be economical, it should produce low emissions (including low NET CO2 production) and it should have good energy density. Currently, petroleum-derived gasoline and diesel meet two of these three requirements, and that is why we use them.

The only fuel solution that even comes close to meeting all three requirements is biomass derived ethanol or bio-diesel. While both fuels have excellent energy density, are essentially carbon-neutral and can be deployed and used within our current infrastructure, they currently cost about 50% more than petroleum derived fuels.

As for hydrogen produced from wind or solar, it is extremely expensive (about 500% higher total cost than an energy equivalent of petroleum based fuel), it has no existing infrastructure for storage or transportation, it is difficult to store in a vehicle and has a very low energy density which limits the range of the vehicle using it.

 

[GregLocock]

Hydroscope , sorry, quantum do have a high pressure regulator. I haven't done the sums, it may be possible to throttle 10000 psi down to typical working pressures without freezing the car up. I doubt it. All the work put into compressing the gas is lost, of course, in most throttles.



Cheers

Greg Locock

 

[HydroScope]

except for CO , CO2 , SOx, NOx, HC, PM just to name a few of the top of my head.

those that have it cheap will export it via hydrogen, like the fact not all the world has crude oil.

if bio-mass is the cheap renewable source of energy it will be gasified into hydrogen, and is far better doing so as I imagine only part of the crop is refined to ethanol or bio-diesel.get mote energy source into hydrogen at the same time having the ultimate control on emissions removing SOx NOx HC and PM. these projects already being elevaluted by CSIRO in pilot plant form.

you have also missed the point that catylitic conv. dont do anthing on start-up for a least three minutes, lean burning is the ulimate for a ICE this is where a catalylists are useless, the reason for diesels emission standards to be trailing petrol. ethanol and bio-diesel don't reduce city emissions at all they are just another source of almost everything except SOx.
hydrogen is the perfect reductant for a lean operating catalitic convertor.

the tank will get cold and doesn't need to be a waste, free air condition when car is left in hot car park, but could also be used for radiator or air inlet when driving ;o)

 

[shbazjinkens]

Bio-fuels reduce nearly all harmful emissions and almost totally eliminate SOx as well as particulates, that isn't minor. Beside that the process of growing the crop recycles more CO2 than is emitted. It won't endanger our food supply because there are so many farmers letting parts of their crops rot to keep prices low or letting fields lie dormant for cash. Algae can be grown in desert land with wastewater that is normally a biohazard. Ethanol can be made from grass clippings either through an (expensive) acid pre-treatment or (inexpensive) biologically engineered yeasts made by Purdue that ferment any plant matter from switchgrass to cornstalks (give that link a read - it's well worth it).

When you look at it from an energy density perspective hydrogen is still a short-range fuel. When you look at it from a cost perspective it is a loser. When you consider practicality in refueling it is a loser. When you look at efficiency.. barely makes it, but not for long.

I'd love to live in a world where such a clean fantasy was possible, but that just isn't the case when you look at the data and reasonably evaluate it, even forgetting the cost. Even though I love the idea of ethanol and biodiesel taking over, that won't happen for a while. Not until it becomes cheaper after factoring in the lower energy density in both fuels.

 

[microhenry]

Don't mix up the total bullshit about the "Hydrogen Economy"
with the meer hype about fuel-cell. Maybe in 2030, fuel-cells
will be practical. I can say with 100% confidence they won't
be using hydrogen. For stationary apps. they'll run on methane,
for portable & transport, it'll be ethanol, methanol, propane....
anything but hydrogen.

 

[TChronos]

It seems to me that the only good point about a hydrogen economy is that you have a common delivery mechanism for multiple sorts of input fuel. You DON'T eliminate emissions if your source fuels are coal, gas or petroleum,and these are the most likely choices in the short run. So the hydrogen economy is basically an admission that there's no obvious replacement for petroleum: in lieu of a replacement, we offer up a translation mechanism that allows us to use any possible fuel they come up with in the future. I'd call that a failure of imagination, rather than a solution.

That being the case, the question is, why does the energy vector need to be hydrogen? Why not something we're already more or less set up for, like electricity? If something more exotic is desired, how about hydrogen peroxide or ammonia? Either would be manageable with more conventional technologies, and just as "clean" as hydrogen. HP can even be used in a fuel cell using common metals like silver as a catalyst.

But if the root of the issue is that petroleum is going away, either by fiat or depletion, then why not bite the bullet and admit that the only alternatives "big" enough to fill the gap are coal, shale oil, and nuclear? The only other possibility I can think of is methane hydrate, assuming that it's not a myth. Fringe technologies like wind and solar can help out with electricity production, but will always be minor contributors. And biofuel without petroleum derivatives is a non-starter.

 

[tbuelna]

Here is a new report from the U.S. National Comission on Energy Policy:

http://www.energycommission.org/ewebeditpro/items/O82F4682.pdf

Begining in Section E (document page 88), there is an excellent discussion on alternative transportation fuels.

Happy reading.

Terry

 

[WoodrowJWeen]

So does anybody in this forum support George W. Bush's hydrogen future. Come on people, he won the election, doesn't that mean he's right about hydrogen?

 

[GregLocock]

Yes, I firmly support a hydrogen future. The more research grants we get, the more toys we have to play with.

Look what we managed to do to PNGV or whatever it was called.



Cheers

Greg Locock

 

[patprimmer]

Hydrogen is not an answer unless it is produced from renewable energy. I feel that is a long way off at this stage, but has some obvious advantages, but some serious problems re storage and safety.

I wonder if once fossil fuels are depleted, if many will re asses there views on nuclear, given some other options and costs. There are already lobby groups against windmill turbines.

I still see bio ethanol as the easiest short term solution

Regards
pat pprimmer@acay.com.au
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[evelrod]

Tell ya what, Woodrow. If old W can pull it off, I'll publically change my position.

I am not too worried as , keep in mind, he is the leader of the free world but does not read newspapers or allow his staff to tell him "bad" news about Iraq. I would copy his entire quote but I'm just "plumb tuckerd out" with the whole political BS.

Pat, we'll get nuclear power one day, fusion (buzz word/term is "cold fusion") but not until we get a new "leader of the free world" because the one we have doesn't know what it is (nuculer!). ;-)

Back to reality---In high school science class in 1954 I first subscribed to Popular Mechanics mag. At the time it was the "consensus"(?) that by the 21st Century Frank Lloyd Wright would have designed and built his "mile hige bldg." in Chicago and we would be landing supersonic international hovercraft on the LZ atop the roof. I was convinced that I would live to see space stations and colonization of the Moon and Mars. We all thought that the petroleum stocks would be "long gone" and power would be by "atomic" means and there would be a private air-car in every garage...
I can guarentee one thing for sure. Looking back fifty years from now---some of you younger guys may well still be around---what you see will not be anything like you thought it would be!

Rod

Believe only half of what you see and none of what you hear!