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Hydrogen Power

Hydrogen Power

Hydrogen Power

(OP)
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?

RE: Hydrogen Power

Yes, I think so, but slowly.

In the UK, the government has a roadmap to a hydrogen future. Paragraphs have now been added stating that there is some question about the efficiency of a hydrogen future and states that the purpose of the document is not to debate the hydrogen efficiency, but only to point out a route to get us there. The authors are therefore sort of beginning to deny responibility.

Also, a chapter, chapter 7 if I remember rightly has been removed. The idea was to store electricity in a reversible fuel cell from regenerative braking. They have deleted the chapter accepting that a battery is better.

Recently I read an article about microturbines and microgenerators being used to generate electricity, for example for cell phones. The author stupidly thought that they could also be used to generate hydrogen to power a fuel cell for a laptop.

So at the same time, we have the idea that petrol engines can create the hydrogen for fuel cells, and elsewhere the idea that hydrogen fuel cells can replace petrol engines.

I think slowly we are going to see an acknowledgement that a 60% efficient hydrogen fuel cell and an 80% efficient electric motor gives efficiency less than ½, and that's before we worry where the hydrogen is coming from.

Hona has a dual use fuel cell product. The fuel cell efficieny is 15% but the heat it produces as a by-product is also used. It serves as domestic powersupply and heater. The total efficiency is then 85%. That's not bad, and its a reasonable use of fuel cells.



RE: Hydrogen Power

That Honda plant is OK, but any reasonable person would use an internal combustion engine, and get 30% as low entropy energy and 30% or more as heat... with the bonus that the reject heat from an IC engine can be at > 100 degrees C if so desired. The reject heat from a fuel cell is likely to be at 80 degrees C, which may be enough for hot water but is not enough for many processes.


Cheers

Greg Locock

RE: Hydrogen Power

Sorry, I hate lazy referencing, so I dug out and reinstalled the Alta Vista search engine on my PC. I have now found the document I had in mind.

http://www.dft.gov.uk/stellent/groups/dft_roads/documents/pdf/dft_roads_pdf_026217.pdf

Its worth a look at PDF page 4/56 as it shows that hydrogen is set to catch up with the ICE in about 2030 if all goes according to plan. The final finish figure is just under 80 grams of CO2 per kilometre, which is not unreasonable. 80 g/km is about the current figure for a VW Lupo 3L TDI or a Honda Insight. The VW is a turbo diesel with 5-speed dual clutch and the Honda Insight is a sleek shaped hybrid. The figures for the cars are tank-to-wheels and the government's aims are well-to-wheels.

Nevertheless its not unreasonable to suppose that combining the diesel efficiency of the Lupo and mild hybrid features of the Insight etc will give the Europeans the sort of 80 g/km CO2 well to wheels they are looking for in 25 years time. (To bring the average down that low is harder, but electric valves, lighter materials and so on are on their way too.)

I've been reading stuff which debunks the man-made global warming ideas recently, but as long as governments are backing the intergovernmental panel on climate change (note, not scientific panel!) there will be a pressure to reduce hydrocarbon imports, and that's no bad thing in itself.

=

So much for me remembering Chapter 7!

Step 6 - Deleted
The original 2002 Low Carbon roadmap Step 6 [1] suggested a reversible fuel cell as an alternative to
a battery for high power storage. However it is now considered that, unless there is a breakthrough in
this technology, it is not as efficient as batteries and the power capacity improvement (allowing more
regenerative energy storage) does not offset the loss in system efficiency. Therefore, this Step has
been omitted in this update. For clarity the numbering jumps straight to steps 7 and 8, as these are
similar to the technologies used in the original study with those step numbers.

RE: Hydrogen Power

I love it when politics overlaps technology. To believe such a MAJOR change in automotive propulsion technology will come about in 25 years is, IMO, a bit of a stretch.  It has taken 35 years to just clean up the engine emissions to today's levels once the politicians decided to make laws governing such emissions.  Should politics again step into the mix and mandate H2 the fuel of choice---the only way it will really happen---it will still take much longer to relegate the old ICE to the graveyard.
Global warming?  Do I not recall correctly that just a few years ago it was "impending ice age"?  I have lived long enough that "the end of the world" will, most probably be a few years, at least, further down the road.

Rod

RE: Hydrogen Power

http://www.phas.ucalgary.ca/~annlisen/teaching/CHEM421/co2hist.GIF

Just have a look what the CO² level was like during previous ice-ages. (That's why many global warming graphs start around 1980!) It seems there is actually a warming effect in progress at the moment, due to increased solar activity. The main greenhouse gas is water, by a long way, clouds serving to help keep night time temperatures up. Very little water vapour is of man-made origin.
But I guess all that is best left for another thread ...

RE: Hydrogen Power

Evelrod wrote:
"To believe such a MAJOR change in automotive propulsion technology will come about in 25 years is, IMO, a bit of a stretch"
Have you noticed that the converion to 42V has stalled, but
GM sez they'll have commercial Fool-Cell cars by 2010!!

RE: Hydrogen Power

I like that---"Fool-Cell"---quite appropriate in this instance!
With the politically adverserial climate existing in the U.S. today I find it not at all unusual, given we are knee deep in bad news that, any good news is being forcast even though it may, indeed, NOT contain a grain of probability.
If the GM says we will all be driving H2 powered vehicles by 2010 who am I to argue?  The fact that it takes GM more than five years just to get a new conventional design in production should not be a factor, should it?


Rod
  

RE: Hydrogen Power

I attended a lecture recently where the topic was global warming and CO2 buildup.  It was shown that CO2 induced warming runs in naturally occuring cycles, and we are about 50 years overdue.  Also, that the Human body is easily adaptable to minute temperature variations.  In the last 100 years, there has been about a 1/3deg F increase in average temperatures, and I dont see people dropping like flies everywhere.  In fact, I have seen record low temperatures in the last couple of years, and a record cool summer here in Texas.

I am looking in my notes for the authors name, will post when I find it.
Franz

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RE: Hydrogen Power

Franz

When I see someone making a fuss saying it is getting warmer because we had the hottest summer in 30 years, that tells me it was hotter 30 years ago.

I will be more concerned when I see reports that say the hottest day, month summer etc ever recorded

Regards
pat   pprimmer@acay.com.au
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RE: Hydrogen Power

Pat--- How much weight should we give "...hottest day, month summer etc ever recorded"  given the current scientific community seems to feel that major climatic changes are in the >10,000 year range?  I put it somewhere near the "fact" that by now all you folks in Oz should be radiated enough to "glow in the dark"--- "hole in the ozone layer" or some such!
Remember, especially in this climate of PCBS---Believe only half of what you see and none of what you hear.

Best wishes for a wonderful Christmas season to all.

Rod

RE: Hydrogen Power

One thing many people don't realize is how non-constant the sun is in terms of an energy source. For centuries we have observed sunspots and they are always changing. There is historical proof that the thermal energy from the sun drops during periods when there are no sunspots. It appears as though the number of sunspots increases prior to a burst of maximum solar output. Lately there has been a regular ~11-year sunspot cycle, and coinciding a few years after each peak we experience El Nino, relatively active/longer hurricane seasons, warmer ocean currents and increases in the ozone hole. Then when the sun cools off these things seem to correct themselves. 5.5 years from now people will be complaining about how cold it is and the "global warming" hysterics will fall silent once again.

Draw your own conclusions:
http://science.msfc.nasa.gov/ssl/pad/solar/sunspots.htm

I don't think the authors of the Kyoto Treaty want you to know how crazy our sun gets from time to time. It's more fun to blame those decadent Americans and Brits!

RE: Hydrogen Power

Well I managed to read through this thread last night and enjoyed conversation, but we seem to be missing some of the threads??, I am unsure why as the controvesy over hydrogen always shifts in the exact manner this thread represent last night. 1) efficiency of hydrogen generation distrubution and final use is not high.
2) green house gas emissions and other pollutants

lets not forget that hydrogen is already produced in large quantities for the manufacture of fertiliers and the petroleum industry. it can be achieved, what is stopping us "hydrogen storage" technology!!. who really cars if our vehicles are 10% efficient or 90% efficent!! If the car can drive 1000kms on one tank, the fuel is comparative in price to petrol and can be readily avalible plenty of petrol stations. if it has the advantage of being enviro friendly then governments will likely step in and mandate they be used.

A lot of people beleive hydrogen has a chicken and egg senerio as what comes first the cars or the stations? comments about certain companies having fuel cell vehicles ready by 2010 are certianly warranted, but the comment about fuel cells being 'Fool cells' is very incorrect. you are a fool not to have taken the time to find what market value fuel cells have at present and what they will have in the future.

there are many different types of fuel cells (further reading fuelcells.org) the type promoted for cars are the polymer electrolyte fuel cell PEFC where advancements are made readily and competition between companies is fierce. but there are others. such as Solid Oxide Fuel Cells (SOFC) these are made of ceramic materials and do not posses the same platinum poisoning that the PEFC's do. the fuel cells can use natural gas and even CO as a fuel. making them very practical for stationary applications. The efficiency of a fuel cell is defined by the gibbs free energy law and is not a a long shot above what a ICE is capable of, instead the quotes of 80% or even 90% are incorrecly made from not useing the HHV of hydrogen and assume the heat generated by the FC is also used. thus first application for FC's is not transport but stationary electrical power and heat.

CrystalClear I think maybe the reason for the removal of the reversible fuel cells from the document, is that out of all the types of fuels cells under developement progress from reversible fuel cells is the slowest and I only konw of one developer for applications on sailing boats in the 1-10Kw range. removing the noisey smelling diesels from the otherwise envir friendly moving boat.

Hydrogen is also not confined to use in fuel cells it can be easily used in ICE. it is capable of 20% more power from an ICE when direct injection is used. direct injection also solves some of the pre-ignition issues that have ocurred in past hydrogen ICE's. A bonus of hydrogen onboard is it's ability to be used as highly efficent reductant agent in NOx traps for lean engine operation ( a problem for diesels). BMW Ford and Mazda are exploring hydrogen internal combustion engines. Ford CEO beleives hydrogen IS the fuel of future and over 20 auto manufactures world wide have already built a FC's vehicles!! so if fool cells are foollish what are they doing?? spend billions because they can?? because governments are happy to hand them tax payers money? or is it because everybody appreciates clean air? and hydrogen provides an answer.

Well I don't think any bold statements about what I beleive hydrogens future is going to be worth while here, but I will leave you with the following senerio's

Vehicle emission restrictions are ever increasing
fuel standards are being raised (lower sulphur etc.)
catalytic converters are reaching there overall potential (start-up still a big problem)
Renewable electrical energy generation size is on the increase Fast!!. i.e wind turbines
some power plants are being refused due to there environmental consequences. redbank Vic aust.

For me these lead to one solution, we need to be able to use renewable electrical energy for almost all applications, since renwable energy can be unreliable we need to store it and hydrogen is the answer, while likely not the most efficient, the efficiency while important it is not the be all if you got a cheap renewable energy source in large quantities to begin with. it is only becomes a measure of the cheapest method of prod. distr. and final use. Take wind turbine competing with coal fired power and now as large as 5MW

http://www.repower5m.com/impress_flash_uk.htm

lets take for example what most cities have to get people around "the bus". here in sydney we have had a succesful project converting most busses to run on natural gas where a small amount of diesel is used to ignite the nat gas. this has lowered emissions where it is most needed the city!

converting this bus to then use hydrogen instead of nat gas is another step in the evolution of lowering emissions. as long as the hydrogen was generated from a renewable source. nat gas does not like to be burned in a lean environment and for all u green house gas fans methane has 21 times the GHG potential of CO2 this means while nat gas busses lower particulate emissions they increase green house emissions over regular diesel, hydrogen like would solve this.

the trends that are going to combine for hydrogen use as a fuel are:

1) larger and larger renewable power stations be it wind, solar thermal, wave, geothermal.

2) Water in australia becoming harder and harder to come by inducing the need for a desalation plant in sydney!.

3) solid oxide fuel cells hitting a large market for use with natural gas. (once hydrogen pipes for distribution of renewable energy, hydrogen will likely be cheaper dispalcing the use of nat gas for electricy and heat)

4) hydrogen readily avaliable and cheap people begin to convert cars to hydrogen and fuel cell vehicles are finally reliable and cheap.

the problem is putting a timeline on these.

p.s crystal clear can you put a link up where all those diagrams came from I sore the other night? I liked what I sore I wish to follow them up. ;o)

RE: Hydrogen Power

Quote:

spend billions because they can?? because governments are happy to hand them tax payers money?

It saddens me to say that the answer is almost universally YES !

HydroScope, I agree with what you post, mostly.  However, at least in the SoCal area, we have thousands of windmills that stand idle most of the time (eg, Palm Springs area)and the Dagget Solar Power Station is never in use when I pass it on the way to and from Vegas!  
H2 will never be in wide use until and unless there is a substantial increase in demand---be it from "real" demand or "legislated" demand and that, IMO,  is not likely anywhere in the near future.  We have the technology right now, today, to build effecient 'hybrid' ( I don't really like that terminology) CI or SI electric compound power plants with little added expense but, and this is a very big BUT, we can't even get the folks around here to give up their SUV's!!!  As long as petrol is only $2.00 a gallon---I guess I need not say more.
Hydrogen power?  Yes, a definate possibility.  Just not by 2010, indeed, probably not by 2030 either.

Rod

RE: Hydrogen Power

My guess is that we won't see hydrogen power as a significant contributor to transportation in our lifetmes (and that includes the 10 year olds reading this).

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

2) No practical method of storage and distribution

3) doesn't solve the fundamental problem

Just in case you've missed the point the fundamental problem is supposedly that we are burning hydrocarbons or carbon and creating CO2 and water.

If we have the energy, via nukes, solar or wind, then we can MAKE hydrocarbon fuels via century old technology, or we can use electric cars.

If we don't have the energy then all this is moot.


Cheers

Greg Locock

RE: Hydrogen Power

Greg, I guess I was erring on the side of caution considering the volatility of the subject of late.  Truth of the matter is that I don't think hydrogen as a motor fuel or power alternative will EVER make a substantial contribution to correcting our transportation problems in the long term.  Short term, interim or special case---perhaps but, not in the long run, IMO.
I am a tecno geek  (at least I have lost enough $ in the market to qualify as one) and my "confidence is high" in the assumption that a solution to our transportation, emission, etc. problems is right "at our fingertips".  Had I told one of my professors that I would be communicating, real time, with engineers in Australia, indeed, the entire world in 40 years I would have been laughed out of class.  Point of fact, no one of that time period, as far as I know, had even envisioned the WWW!  There is a chance, remote that it may be, that I will still be here in 30 years---I'll get back to you then.

Merry Christmas, Greg

Rod

RE: Hydrogen Power

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


hydrogen(from renewable source) ICE will rid these to almost unreadable levels (SOx,CO,CO2, PM) and substially lower the other NOx

a hydrogen FC has the potential to do further zero SOx NOx CO CO2 and PM!! problem solved!!

. . . . well not really as if a Life cycle assement is made then emission and pollution are made by limestone manufacturing to concrete for wind turbine foundation etc. and steel works and platnium mining etc. but these add up to be far lower the current expoltion of exhast emissions.

Also I was supprised to get my hands on N.S.W average pollution levels readings for the last 30 years to see all but PM and ground Ozone, has reduced dramatically. cheers to unleaded fuels and catalitic converters. but what these have no effect on is the increase in population over the last 30 years. If you bought a house in sydney 30 years ago you probably would have bought one 10Kms from the center of the city, since then the city has expanded 10times and now everyone is driving past your house pulling up for traffic lights and accelerating away. my point is local pollution, almost dosn't matter where you live it has increase likely 100 fold in the same 30 years average pollution gone down. thus a better answer needs to be found. Hydrogen. for above reasons.

If we have the energy, via nukes, solar or wind, then we can MAKE hydrocarbon fuels via century old technology, or we can use electric cars

as far as I am aware the chemical reaction in a battery can be summarised as hydrogen Ions moving through an electrolyte. lets remove the heavey electrolyte and carry hydrogen on it's own, yes hydrogen storage still needs large improvements but they are happening.

synthetic manufacture of hydrocarbons fuels is reality. but if you are talking about growing crops for ethanol and bio-diesel. how much land is needed for these crops? and they don't even solve the problem of NOx, CO, PM , these are ever increasing on a local basis.

If you are talking about using hydrogen generated by renewables to be catalytically combined with carbon to produce say methane, ethane or ethanol etc. the above problem is still true.

"Had I told one of my professors that I would be communicating, real time, with engineers in Australia, indeed, the entire world in 40 years I would have been laughed out of class.  Point of fact, no one of that time period, as far as I know, had even envisioned the WWW!"

 . . . . . my point exacly . .. in one word . . . nanotechnology . . . ;o)

RE: Hydrogen Power

Quote:

. . . . . my point exacly . .. in one word . . . nanotechnology . . . ;o)

Accepted.  My opinion still stands.  Hydrogen as a motor fuel will, in all probility, never have a major impact on the transportation industry in my lifetime, if ever.

Rod

RE: Hydrogen Power

You seem to be missing a very valid point Hydro.. when you make Hydrogen it is either made cheaply with fossil fuels or expensively with clean electricity. How many square miles of windmills and solar collectors do you think it'd take to produce the required electricity to split water into hydrogen at less than 50% efficiency? At what cost? If fossil fuels are used to make the hydrogen is it any better than burning straight from the vehicles?

I think we'll see veggie oil and ethanol come into play when the oil supplies start dwindling. There are a lot of reasons for that, new tech and brilliant ideas that no one with cash is pursuing right now.

RE: Hydrogen Power

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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RE: Hydrogen Power

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.

RE: Hydrogen Power

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

RE: Hydrogen Power

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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RE: Hydrogen Power

"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

RE: Hydrogen Power

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/

RE: Hydrogen Power

Quote:


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.

Quote:


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.

RE: Hydrogen Power

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 - 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)

RE: Hydrogen Power

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

RE: Hydrogen Power

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.

RE: Hydrogen Power

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

RE: Hydrogen Power

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)


RE: Hydrogen Power

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.

RE: Hydrogen Power

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.

RE: Hydrogen Power

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.

RE: Hydrogen Power

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?

RE: Hydrogen Power

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

RE: Hydrogen Power

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
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.

RE: Hydrogen Power

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!  

RE: Hydrogen Power

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
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.

RE: Hydrogen Power

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

RE: Hydrogen Power

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.

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.

RE: Hydrogen Power

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.

RE: Hydrogen Power

Hey evelrod!!  The future just ain't what it use to be :)

RE: Hydrogen Power

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.

RE: Hydrogen Power

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.

RE: Hydrogen Power


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.

RE: Hydrogen Power

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.

RE: Hydrogen Power

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.

http://www.health.nsw.gov.au/pubs/2004/airpollutants.html

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. . .

http://www.ford.com/en/innovation/engineFuelTechnology/hydrogenInternalCombustion.htm

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.

http://www.dep.state.fl.us/secretary/news/2005/01/0109_01.htm

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.

RE: Hydrogen Power

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

RE: Hydrogen Power

    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.

RE: Hydrogen Power

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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