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Hydrogen Power

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CCycle

Automotive
Oct 3, 2004
68
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?
 
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Rod

We are currently powered by nuclear fusion, it's just that we never built the reactor, and it's quite a long way away.

Who is Woodrow, Woodrow Wilson?

It really worries me when the leader of the "free world" rigs elections and can't even pronounce a simple 3 syllable word.



Regards
pat pprimmer@acay.com.au
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late response here


"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."

uh- you DO realize that it isn't the "poisonous" quality of exhaust that does it? Car exhaust (if spark ignition and not diesel) is CO2 and water vapor, with essentially NO Oxygen.

... "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"

That is a BS quote- you don't use coal for peaking, and if you do, you accept that it is expensive but only for a few hours a day. Those are "scare" numbers for the ignorant.
So, Tas claims that wind is down to the cost of the most expensive coal plants.
That's nice.

What do they do to average the output so they have power available when the wind isn't sufficient?
Oh, yes- you use "peaking" power?
big gain there...

"efficiency means nothing when you have a cheap renewable source of energy."
Maybe the tooth fairy will bring us one?

grumble...

Jay

Jay Maechtlen
 
If you grow the ethanol, you only put the water and carbon dioxide back that you took out to make it. Net result, no change.

It is the carbon monoxide that poisons people with the exhaust. To get any quantities of that in this day and age, you have to have a very old car, or a defective newer one.

To smother (not poison) someone with carbon dioxide and water vapour, you would need to go to considerable trouble to seal off all sources of oxygen, then displace the available oxygen.

Carbon dioxide and water do not make a brown haze, and both exist in the atmosphere naturally in substantial quantities.

Localised increases in water will only increase the humidity, and localised increases in carbon dioxide will only possibly cause us to breath a little heavier. This is used to advantage in medical quality resuscitation air.

It is high cylinder pressures that cause the oxygen and nitrogen that are naturally in the air to combine to form NOx, which does make brown haze, no mater what fuel was used, so long as ambient air is used as the oxidant and so long as the cylinder pressures get high enough to trigger the reaction to form NOx.



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pat pprimmer@acay.com.au
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Pat--In the U.S. , at least, ethanol motor fuel produced from corn is an extremely marginal proposition from an energy balance standpoint. A gallon of ethanol contains 77,000 BTU's. According to research done at Cornell University, it takes 131,000 BTU's to produce that gallon of ethanol.Now, the ethanol lobby counters that the 131,000 BTU figure is from state of the art plants presently in operation and with best in class plants, it would take less energy to make the ethanol. But even with more efficient plants, you don't get to a positive energy balance until you start adding back the energy imparted to cows when they are fed the distiller's grain, which is the spent mash from the fermentation process.
 
I'm not all that interested to see a hydrogen powered world but ever since the 1964-65 World's Fair, I have been hoping to see flying cars. Probably not a technical impossibility but can you visualize today's drivers operating in 3 dimensions.
 
swall

Thanks for the figures.

This is not my field, and I am only assessing this intuitively.

I was not aware of the production costs. I presume the growing costs should be very low, depending on farming practises, but the fermentation and distillation process I would expect could consume considerable energy.

We currently have a huge excess in sugar cane capacity here in Australia, so there is a motive to push this. We also have a lot of sunshine in our sugar cane growing areas, so I expect that solar stills might be feasible, once the costs of fossil fuels increases above a certain level.

I wonder if burning the cane to produce the energy to process the sugar might stack up.

I expect Cuba might be in a similar position re excess sugar cane capacity.

Regards
pat pprimmer@acay.com.au
eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
 

with regard to the energy yield for ethanol -- you're right that ethanol from corn starch (most of current US ethanol) isnt a reasonable long term proposition. The main hope for ethanol is to generate it from cellulosic biomass--all the stalks and husks and other agricultural waste (including even urban paper waste). The leaders in the field in N America are Iogen (canada) and BCI (US). I think they still require subsidies to be competitive, but the costs are dropping. BCI has recently set up a large scale plant in lousiana (I think) that uses waste from sugar beet harvesting. They have plans for another in california that will use rice husks. The cellulose feedstocks are essentially free, and it leaves the rest of the plant to be used for better things.
 
If I recall, Brazil went the sugar cane route big time in the late 1970's.I believe they got to where ethanol was meeting 25-30% of their motor fuel needs.They were burning straight ethanol and possibly some E85 blend. As for biomass ethanol, I've seen it proposed that tree farms growing hybrid poplar trees could be dedicated to ethanol biomass feedstock. If a good growing environment is selected, you just let the poplars do their thing and grow, without the fertilizer and herbicides that corn requires.
 
I am unsure why so many of you keep refering to Carbon dioxide as the worst thing coming from the exhaust pipe you might like to take a look at this report.


it describes the most of the toxins from ICE. This report really states what I’m getting at. We have done a great job of reducing ambient emissions the next step is to reduce the emissions from where most of us live, work and play, directly next to a operating ICE.

NOx formations are from directly related to high in cylinder temperatures not pressure.

this was on the net before but I couldn't find a link this time round.

C.K. westbrook and W.J Pitz, 1999 "The Inevitability of engine out NOx, emissions from spark igntion and diesel engines" Lawrence Livermore National Laboratory

Hydrogen has a wide flammability range thus can easily be used for lean burn operations, Nox is not generated at all during this process due to low temperatures. This is true up to 40% of power output, the lack of power from lean burn operation can be overcome by turbo or supercharger in the way it is done by Ford. . .


As an extension of what I was saying earlier, hydrogen powered ICE buses would be the logical next step in removing high levels of pollution from CBD areas of any large city, FORD has just announced the release of commercially available hydrogen powered buses.


The rail network is stuffed up here in Sydney, add to that we have a huge country and rail does not service all of it, to the point we are home to very large trucks, recently I looked at the cost and time to get around our states via so called government owned and operated trains vs privately owned buses. Train should be cheaper and faster shouldn’t it!, but it isn’t, I say get rid of the city rail infrastructure and put in bus and road train lanes Bold I know. Why am I mentioning this, I think it also related to emissions, the rail network is electric with no emissions in the city, with low emission buses followed by zero emission busses later this is a better idea, more flexible routes can be taken with buses then trains, and they seem to be cheaper overall.

Jay always happy to have a better late than never reply but my Quotes aren’t BS!! and I gave my reference “ABARE” as far as I know they are a reliable source, if you have access to other numbers more reliable then let us all see!! The idea was merely to give a reference to other power generation costs as stating $50 doesn’t mean a lot until you have a reference. You could have of easily replied coal off peak is so much lower than wind thus coal will for a long time be the main source. That is obviously your opinion. I’m well aware coal isn’t always fired up to full capacity for peak loading, hydro dams are useful for this. In Tasmania they use off peak wind power to pump water up hill, for later peak demand as well as using dams in large catchment areas.
 
refrigerating the charge?
very strange- that could be the topic of another thread.
Not BS?
"the average $80 - 100" - meaningless statement, as peaking should be only a few hours of the day out of 24.

The other ABARE numbers may be valid, but they do not support your position very well.
It is not so useful to compare peaking cost of one fuel/system to the running cost of another.
I've heard of using pumped hydro for load levelling. Probably a reasonable approach for things like wind and solar power which aren't necessarily available 'when needed'.
Nevertheless, if you are using your wind, etc. you must factor in the effective delivery cost, not the raw plant cost.
For that matter, if coal plants can be run at most efficient load levels, then the hydro peaking may be cheaper than gas turbines or other methods.
I wonder what the primary sources of the BTEX pollutants are- ancient and poorly maintained vehicles?
Does OZ have evap emission controls on vehicles and refueling like we do here in SoCal?
cheers
Jay


Jay Maechtlen
 
Just thought that I would provide some numbers on reductions in pollants to the atmosphere in the USA. The numbers are from the US EPA and are the percent reduction from 1970 to 2001. Here they are:

CO -19 %
NOX +15 % (the only one listed that increased)
VOC -38 %
SO2 -44 %
PM -78 %
Lead -98 %

Looks like catalytic converters and cleaner fuels are making some pretty big reductions in pollutant levels in the US.

I don't have a number for CO2 emissions. I suspect that CO2 emissions have increased significantly since 1970 since our economy has grown during that time.
 
J2,

Australia has IDENTICAL results except we have also reduced NOx, you have left out ground level O3. mypoint about local emissions can be seen from the reading that report exposure to NOx in car and bus respect. 29.7, 44.3 ppbv. While ambient condition on the same days instead at weather station record 7.42, 6.39, 13.43 it is from these figures that the ambient air conditions are taken, yet they have little bearing on what we breath during our day of work rest or play. worse case senerio exposer while sitting on bus is 7 times ambient. best case senerio 2.2 times sitting in a car. each mode of transport and each polutant shows much higher levels than the ambient levels. See if there is a similiar report in america, I have been to LA and I don't think the air there could possibly be cleaner than sydneys.

I own a 1989 model car and it has a vap emission controls.
 
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