Does anyone have numbers on Hydrogen?

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swbluto

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I think batteries suck for long distances primarily due to associated costs and the relative infrequency of taking advantage of "300 mile" range capabilities. For chemicals, it's pretty nice, because your cost is proportional to the total distance that you travel as opposed to your vehicle's maximum range.

So, looking at energy density diagrams, it appears that hydrogen has a lot going for it. It can be made from water with a total cost less than that of gasoline using electrolysis, and that process would be "clean". The drawback was the volumetric energy density - it had to be either in liquid form(really really cold? Would that be possible to contain?) or very highly pressurized. In liquid form, it had 4 times less the energy density of gasoline and in gaseous form at 700 bar, about 8-10 times the energy density of gasoline. In gaseous form, it would have about 5 times the energy density of lithium-ion. Assuming a hydrogen engine efficiency of 25% as opposed to an electrical system's efficiency of 70%, it seems one can expect a per-mile volumetric energy density of 1.7 times that of the lithium ion batteries (3.5 times in liquid form). I have no idea what volume the containment system would need, but it seems like it could be smaller than a similar lithium ion battery. So, one might need to allocate more space for longer distance than gasoline - so just bring a trailer or something.

So, with hydrogen, it seems like it would be possible to have a high theoretical maximum range on a hybrid vehicle while also remaining "clean" while retaining the low operating costs of an electric. I have no idea how much the upfront is for a hydrogen system, though (Hydrogen engine? Electrolysis system? Hydrogen container? Hydrogen compressor?). I also have no idea how practical bring the hydrogen charger(I.e., electrolysis system) would be and... plugging it in somewhere if you're traveling cross-country.

Any ideas? Any Endless-Sphere's of the hydrogen world?
 
Hello,

I've thought about this subject and would like to share a few thoughts.

I make H2 in the garage via electrolysis and have been doing so for several years now. And I think water, as strange as it sounds, is an excellent fuel source. In proper stoichiometric ratio burning at up to 5700 deg F and 4000 deg F in air.

I shot my idea of an IC vehicle running on H2 to an engineer friend of mine. And his response was logical. He said that the conversions from (lets start at grid instead of alternate green source) he said to go from grid, to electrolysis, to H2 storage, to combustion, to mechanical power (and in my case to electrical generation to battery, then more mechanical power) there are so many losses in conversions that it takes some of that energy density away in efficiency losses. He said it be much better to go full electric, or H2 fuel cell. My retort was, "Dude, H2 shoots out a flame and goes boom, its worth the losses!"

So despite the warning I've been slowly developing an engine of sorts. Yes your right about the densities. Some of the downfalls of storage not mentioned are: because of the small size of the H atom it will slip through Fe for example slowly leaking the whole time, as well as causing some metals to brittle. I'm currently a bit stuck on a good DIY H2 compressor those are expensive as hell, and as a DIYourselfer you can almost forget doing liquid as you have to deal with some crazy hurdles such as insulations and parahydrogen, see spin isomers of hydrogen if your curious. One of my designs uses a scuba tank at high pressure, non liquid, for daily filling.

Something else is that water vapor is the worst greenhouse gas, if we all burn H2 will that be more detrimental than methane and carbon dioxide to the atmosphere? Because of the above difficulties I've now focused my interest to methanol. Has a higher energy density than batteries, and it's easy to store. Not only that, I can still use my H2 electrolysis setup to make it. But it does give off CO2 when it burns. So in order to make it carbon neutral you would need to sequester the CO2 from the air, power plants, etc, and combine that CO2 and H2 --> CH3OH (methanol). The catalyst is the tricky part ;)

I found a good read about hydrogen as a propulsion fuel in "nasa H2 history" check it out. You'll find some numbers there. And another one is George Olah's "Methanol Economy". If anybody would like to contact me about this subject, or any clean energy chit-chat, I've created an IRC channel called #clean-energy @ irc.freenode.net so if you have an irc client come on in, its currently empty but wouldn't mind folks interested in this stuff to share links, ride pics, figures etc.

There are currently H2 powered ICE on the road, and a motorcycle in the works so I definitely see its use in even smaller vehicles. All in all I think Hydrogen is in our future for transportation. Along with algae bio fuels, electric storage, and methanol. We can kick the oil. And really its the sun we need and have for the above. A quote from Thomas Edison: "we should be using natures inexhaustible sources of energy — sun, wind and tide. ... I'd put my money on the sun and solar energy. What a source of power! I hope we don't have to wait until oil and coal run out before we tackle that."

Cheers.
Jasper Mine
jsplifer at that yahoo place
 
Be careful with the methanol. I got a methanol exposure from packaging it at work that resulted in BLINDNESS for a few hours. It is toxic. It might be that I'm just getting old (46) but my eyesight seems to be getting worse at an accelerated rate since the exposure.
 
jsplifer said:
Hello,

I've thought about this subject and would like to share a few thoughts.

I make H2 in the garage via electrolysis and have been doing so for several years now. And I think water, as strange as it sounds, is an excellent fuel source. In proper stoichiometric ratio burning at up to 5700 deg F and 4000 deg F in air.

I shot my idea of an IC vehicle running on H2 to an engineer friend of mine. And his response was logical. He said that the conversions from (lets start at grid instead of alternate green source) he said to go from grid, to electrolysis, to H2 storage, to combustion, to mechanical power (and in my case to electrical generation to battery, then more mechanical power) there are so many losses in conversions that it takes some of that energy density away in efficiency losses. He said it be much better to go full electric, or H2 fuel cell. My retort was, "Dude, H2 shoots out a flame and goes boom, its worth the losses!"

So despite the warning I've been slowly developing an engine of sorts. Yes your right about the densities. Some of the downfalls of storage not mentioned are: because of the small size of the H atom it will slip through Fe for example slowly leaking the whole time, as well as causing some metals to brittle. I'm currently a bit stuck on a good DIY H2 compressor those are expensive as hell, and as a DIYourselfer you can almost forget doing liquid as you have to deal with some crazy hurdles such as insulations and parahydrogen, see spin isomers of hydrogen if your curious. One of my designs uses a scuba tank at high pressure, non liquid, for daily filling.

Something else is that water vapor is the worst greenhouse gas, if we all burn H2 will that be more detrimental than methane and carbon dioxide to the atmosphere? Because of the above difficulties I've now focused my interest to methanol. Has a higher energy density than batteries, and it's easy to store. Not only that, I can still use my H2 electrolysis setup to make it. But it does give off CO2 when it burns. So in order to make it carbon neutral you would need to sequester the CO2 from the air, power plants, etc, and combine that CO2 and H2 --> CH3OH (methanol). The catalyst is the tricky part ;)

I found a good read about hydrogen as a propulsion fuel in "nasa H2 history" check it out. You'll find some numbers there. And another one is George Olah's "Methanol Economy". If anybody would like to contact me about this subject, or any clean energy chit-chat, I've created an IRC channel called #clean-energy @ irc.freenode.net so if you have an irc client come on in, its currently empty but wouldn't mind folks interested in this stuff to share links, ride pics, figures etc.

There are currently H2 powered ICE on the road, and a motorcycle in the works so I definitely see its use in even smaller vehicles. All in all I think Hydrogen is in our future for transportation. Along with algae bio fuels, electric storage, and methanol. We can kick the oil. And really its the sun we need and have for the above. A quote from Thomas Edison: "we should be using natures inexhaustible sources of energy — sun, wind and tide. ... I'd put my money on the sun and solar energy. What a source of power! I hope we don't have to wait until oil and coal run out before we tackle that."

Cheers.
Jasper Mine
jsplifer at that yahoo place
Click to expand...

Thanks for your response! I think my usage patterns tends to fall in the part where long-distances are planned and daily distances could easily remain within the affordable short-distance capacity of batteries. Since the long-distances are planned, I could fill up right before a trip and as long as the hydrogen losses are low enough (Say, less than 10% per day), I could refill everyday overnight during charging. But, I have no idea what the inevitable hydrogen containment losses are. I also don't know how practical "hydrogen charging" would be (Either for the refrigeration or the compression, which are expensive from what I've heard.) on the go (Could it charge in less than 6 hours?), and whether it could be charged quickly enough to enable long distances. The only part of system efficiency I'm worried about is from the time one takes off on the road (Which might result in an effective volumetric energy density less than lithium, but, what the hey, the point is to keep the costs low for long distance capabilities although it sounds like the compressor or refrigerator might be a cost problem); the other parts of the system efficiency equation will turn up in the electric bill which I think could be cheaper than gas per mile.

The other part of air pollution equation will just result in water. Excess water gets quickly filtered out of the atmosphere in the form of rain, so I'm not too worried about the gas sticking around long. But... if everyone does it, then I'd imagine the average amount of the water in the air would increase which might increase warming. But, in this scenario, it'd stabilize at some H20 level, unlike CO2 which apparently accumulates, though CO2 might stabilize in the long-term through large corrections from who knows what.
 
Always possible that some unexpected "X-factor" development will provide a breakthrough, but currently I am not bullish on H2 as a mobile fuel. As I'm sure you know, a fuel-cell car is an electric car, that gets its electrons from a membrane that strips the electrons off of H2 molecules with no burning.

Storage and transportation of liquified H2 (with venting losses due to warming) is hugely expensive with no breakthroughs in sight. I've read that compressed dry H2 in rooftop cylinders has been used on prototype busses. Even at 4,000-psi the range was short, but the cylinders can be recharged fairly quickly from equalising with larger higher-pressured cylinder at a fuelling station. While the bus is driving, the station compressor system is recharging and cooling the staging tank.

For burning H2 in an ICE, Ford did a study to find out what it would take with real-world off-the-shelf hardware to produce an H2-burning 100-HP engine (made from a naturally-aspirated 100-HP gasoline engine). They took a new 4-cylinder engine they make, and added a blower, a turbocharger and a two intercooling systems.

H2 ignites easily and compression (whether from a high compression ratio or forced induction) can significantly raise cylinder temps. Hot exhaust valves have been known to ignite H2 before the spark event. Gasoline-turbo enthusiast know very well that cooling the compressed gasses can allow more compression. Intake air and H2 are compressed (and thus heated) by a conventional turbo and cooled by a common air/air intercooler.

Then, they are further compressed by a positive-dispacement blower, and then cooled the gasses (H2/air) again by a freon heat exchanger. The car had two air-conditioning systems. One for the passengers, and one for the engine intake. Gasoline burns in a 14:1 ratio with air, H2 must burn in a roughly 2:1 ratio (2/3rds air, 1/3rd H2), so for a same displacement engine, there is much less air available to make power. One way to envision this is that a naturally-aspirated big-block V8 burning H2/air might have the same power as a small gasoline-burning 4-cylinder.

I researched this when figuring out how to make a small wind-gen that electrolyzes water to make a small amount of stored H2 to use as a cooking gas substitute for a remote cabin (rather than hauling in propane). Steel propane containers can be coated internally to store H2.
 
Hello,

Here is a bit more to think about. Your proposing something like Fig. 1. Portable and small like Fig. 2?

A breakdown of Fig. 1:
  • 1. Power Grid
    2. DC Power Supply and Electrolysis Unit
    3. Air Compressor
    4. Air Tank
    5. Air Tank
    6. Internal Combustion Engine
    7. Generator
    8. Battery
    9. Controller and Motor

With my small electrolyzer like in Fig. 2 below (the only real component btw) I can generate 4 L per minute using 40 amps at 12 volts of H2 and O2. So 2.6 L of H2. My larger 75 plate dry cell electrolyzer is much more efficient but way too much apparatus for any kind of light weight trip.

Lets say you have a tank like in Fig. 6. That could hold about 600 L of H2 at around 2750 psi. That would take around 4 hours to fill. So this is where we run into a problem. A compact compressor like one used in air-brushing only hits 60 psi. Large garage units only hit 200 psi. Your talking fairly major power consumption. And a whole lot more energy to liquify 55,556 W h/kg versus 3889 W h/kg. I really have to stress that I seriously doubt its possible to hit -400 deg F in a travel H2 charging kit, or a compressor hitting that pressure for that matter.

There are more efficient, and some expensive, methods out there. For example you would be better off with a fuel cell (would eliminate 6. and 7. from Fig. 1) and its been said you could use lower H2 pressure if you had say, a tank full of burnt chicken feathers, which simulates carbon nano tubes and absorb a lot of H2 (reduce requirements of 3. in Fig1). Be careful when you read, 50km on 1 liter of H2 in articles, that might mean the tank volume, not necessarily the volume of gas inside it. This is pretty cool. http://www.designboom.com/weblog/cat/16/view/8165/hydrogen-bike-by-acta-energy.html

How much energy is 600 L of H2 at ambient pressure? The answer would be 1,700 watt hours, but will your ICE capture that? Lets assume a generous 20% efficiency= 340 watt hours. And you still have to go through a generator, battery, controller, and into the motor. So lets imagine two big scuba tanks as saddle bags. That would equal 8,500 L with 100 extra pounds of weight for the tanks and it would have 25,262 watt hours, or about the same energy as 3/4 of a liter of gasoline. It would take 54 hours to fill with a small electrolyzer. Compare this to how much energy you use in your normal A. to B. ride of 1 kilometer in varying terrain and extrapolate this to planed distance to find out how many times you would need to stop and recharge or the tank size you would need. Compare the energy to compress the tanks, versus opportunity charging. Compare the cost of a fuel cell versus the cost of refrigeration :)

Fig. 1
Fig1-20091220-222051.jpg


Fig. 2
Fig2-20091220-185201.jpg


Fig. 6
Fig6-20091220-222227.jpg


Figures 3, 4, and 5 were removed as I went a little too long for one post already. Was some photos of the basic components for my little electrolyzer so that it might be replicated. Some other time though.

And to conclude, it doesn't seem feasible to refrigerate, or to use high pressure with ICE in a travel kit. But a low pressure H2 tank and a fuel cell would certainly fit your requirements. :) Worth further investigation untill we get the little helmets. With tiny solar panels on them. That like, power a tuning fork inside a fuel tank of water. Producing on the go hydrogen. w00t!

Cheers,
Jasper

Math not checked for accuracy.
 
I suppose a hydrogen fuel cell that produces electricity might make the most sense for an electric hybrid. I got the sense that the power density of (current) fuel cells isn't really that great, but they still retain excellent effective energy density compared to LiFePO4 for example, so you could have the batteries provide the bursts of power when you need it, while having the hydrogen fuel cells to give long-distance, relatively low-power cruising capability.

Now I just need to find hydrogen fuel cells.

I'm really thinking along the lines of a highway-speed, long-distance capable three-wheeler. While one may need 10 kW to sustain 60-70 mph, I'm thinking that a large enough energy capacity hydrogen system to sustain a reasonable 300 to 500 miles a day should be able to easily sustain 60-70. I'm not averse to having a "hydrogen fuel-cell trailer" that I could attach for the long-distance trips, so I don't think the most demanding requirements, the volume requirements, would be a problem. Just make it long enough, assuming one maximizes the trailer's cross-sectional area without significantly impacting drag.

(I'm getting an eerie feeling that high energy capacity hydrogen fuel cells run into the same cost problems of high-capacity traditional batteries. Although, it appears wikipedia is pricing hydrogen fuel cells according to power, so maybe energy capacity isn't a huge cost problem like with batteries?)
 
Some info I found some time back on the fuel cells. Really, need one of the H1000 units for it to be usable. Then you will need fuel to make it werq. We are not quite there yet as you have said but we are getting closer. There is one fuel cell motorcycle out there I am aware of, beautiful it is, but way spendy, looks to have little torque and is not all that great in the top end either. Info gleaned from watching a video of it in action. Oh and if you have the money to use these let me know and I will get in line to be your friend. ;^)


http://www.horizonfuelcell.com/store/h1000.htm

Part of an email they sent me when I reqested prices below.

Thank you for your interest in Horizon products and the fuel cells that we are offer are complete systems, which are ready to run (with one external 13V power supply for the controller). When the output is 48V and 15A, the hydrogen consumption is about 8L/min.

Please find the pricing as follows:

H-500 $3435 24A @ 21V 6.2LBS

H-1000 $4000 23A @ 43V 9.3LBS
 
biohazardman said:
Some info I found some time back on the fuel cells. Really, need one of the H1000 units for it to be usable. Then you will need fuel to make it werq. We are not quite there yet as you have said but we are getting closer. There is one fuel cell motorcycle out there I am aware of, beautiful it is, but way spendy, looks to have little torque and is not all that great in the top end either. Info gleaned from watching a video of it in action. Oh and if you have the money to use these let me know and I will get in line to be your friend. ;^)


http://www.horizonfuelcell.com/store/h1000.htm

Part of an email they sent me when I reqested prices below.

Thank you for your interest in Horizon products and the fuel cells that we are offer are complete systems, which are ready to run (with one external 13V power supply for the controller). When the output is 48V and 15A, the hydrogen consumption is about 8L/min.

Please find the pricing as follows:

H-500 $3435 24A @ 21V 6.2LBS

H-1000 $4000 23A @ 43V 9.3LBS
Click to expand...


If $10,000 could get me a system that could sustain 70 mph on the flats while getting 300-500 mile range and assuming it'd last a long time, then that seems like it'd be better than batteries that would effectively last 10 years and provide a 120 mile range while also substantially increasing mass (Which would drastically cut down range in mountainous terrain).

Also, I'm checking out the FCX clarity at http://en.wikipedia.org/wiki/Honda_FCX_Clarity, and this...

The range on a full hydrogen tank (4.1 kg @ 5000psi) is 280 miles (~450 km), with fuel efficiency of 77/67/72 miles (~124/108/116 km) per kilogram of hydrogen in city/highway/combined driving.
Click to expand...

sounds unbelievable! 280 miles on effectively 10 pounds of hydrogen? That sounds lighter than gas and obviously much lighter than equivalent LiFePO4 batteries. The only thing the car doesn't provide is an onboard compressor so you're dependent on a hydrogen refill network. If the air compressor is really that expensive, then I guess it makes most economic sense to have it shared amongst a large amount of people via refill stations which poses long-distance capability problems. How expensive are they, though? 5000 psi doesn't sound like a lot. I'd be ok with an "over-night" charge, assuming it isn't too loud. :)
 
Decent compressors that get into the 3K range are several thousand dollars. For 5K and likely pumping a volatile gas such as hydrogen, it would be much more. I am still waiting for better batteries and less expensive more durable fuel cells. Hope they get here before I am too old to care. ;^) There is so much tech out there that has yet to trickle down to the consumer. Once you do a little research on just about any subject you can see the tip of the iceburg.
 
I used this site a couple of years ago to inform my self on Hydrogen.

http://knowledgepublications.com/index.htm

H2 has a extremely fast flame spread. To make up numbers, gas vapor in a "glass" tube will spread somewhere in the 1000 ft/sec range. H2 would spread in the 5000/sec range.

I don't have the books in front of me but you can burn h2 with any kind of fuel, you just need to adjust the timing. Roy McAlister Has done so with dried up orange peels and diesel.
Roy use the metaphor of throwing gas on a fire

Since h2 burns so fast you can set the engine timing to tdc with pure h2.

If you set up a wind mill or solar to make the h2 then you wouldn't have to worry how efficient the conversion is.

Also, the pressure going into the electrolysis = pressure coming out.
 
IIRC buried in here:
http://www.youtube.com/watch?v=eSevs_uAuQw Evaluating Energy Solutions to Climate Change
somewhere is information about hydrogen usefulness as a power storage medium. It's one of those interesting Stanford university lectures. It's 50-60 minutes (IIRC) long, so only watch it if you're interested in the subject generally. IIRC the conclusion was not to use H2.
 
Ahhhh hydrogen, one of my favorites. First, hydrogen is really an energy carrier, not an energy source. Reason? See any free hydrogen laying around outside of the protons in the sun? So it has to come from somewhere. If you burn fossil fuels at the power plant it is a non starter. If you strip it from natural gas, that is fine for the amounts NASA uses, but not for powering our country. So right now the only appropriate source is electrolysis downstream of a nuclear reactor... we don't have enough reactors on line. Next best is the DOE research in high temp nuclear to help with the splitting/electrolysis; but it is in research TRL-4 level.

So right now if we could use the hydrogen, we cannot produce any where near enough.

Now for fuel cells. Proton Exchange Membrane PEM fuel cells are great on hydrogen, but there is not enough platinum in the world to fabricate the installed base that would be required for a world wide conversion. So we are not likely going there.

Next up is Solid Oxide Fuel Cells. They burn hydrogen well, and I have even seen them running in a small scale like 1KW very successfully in a small entreprenurial shop near me. Their problem is the ceramic core. They must be heated very carefully to be brought up to full power. Basically they like being "on" all the time. So they don't work very well for intermittent transportation.

Government has spent a lot in these areas. You can find reports in the open that will back up what I have said above.

Oh one last good tidbit. I personally ran lean burn gasoline engines well beyond the normal 22:1 air:fuel ratio by injecting about 2 or 3 percent hydrogen to remove cycle to cycle variation and to improve ignition around 1970. The gas mileage was phenomenal. We were a little above the current Nox signature with a three way catalyst though. It was fun times. Also beware of the engineering problem of hydrogen embrittlement when building and using hydrogen in systems. It can be a killer. Also mind the 4% to 96% combustion concentration ratio. Basically anything from a little to almost pure hydrogen/air will burn.

Finally, I promise this is really the last tidbit. Hydrogen is surprisingly pretty safe in a wreck. It is buoyant and the fireball goes up with little incandescence and radiation. Much safer than a propane boiling liquid vapor explosion, or a gasoline pool fire. There is good literature on this too in the open.
 
Spinningmagnets,

Are you sure about your ratios? Perhaps you were thinking of the hydrogen to oxygen ratio for perfect combustion? Two parts hydrogen to one part oxygen. If that was the case its a bad ratio to use in an engine, because of the perfect combustion, extremely high temperatures are reached.

Gasoline burns in a 14:1 ratio with air, H2 must burn in a roughly 2:1 ratio (2/3rds air, 1/3rd H2)
Click to expand...

fuel_air_mix-20091221-123033.jpg


swbluto said:
The range on a full hydrogen tank (4.1 kg @ 5000psi) is 280 miles (~450 km), with fuel efficiency of 77/67/72 miles (~124/108/116 km) per kilogram of hydrogen in city/highway/combined driving.

sounds unbelievable! 280 miles on effectively 10 pounds of hydrogen? That sounds lighter than gas and obviously much lighter than equivalent LiFePO4 batteries. The only thing the car doesn't provide is an onboard compressor so you're dependent on a hydrogen refill network. If the air compressor is really that expensive, then I guess it makes most economic sense to have it shared amongst a large amount of people via refill stations which poses long-distance capability problems. How expensive are they, though? 5000 psi doesn't sound like a lot. I'd be ok with an "over-night" charge, assuming it isn't too loud. :)
Click to expand...

swbluto,

Some conversions.

4.1 kg of H2 is 45,600 liters. Under pressure of 5,000 psi it takes up the volume equivalent of a 50 gallon gas tank, providing a potential 135,523 watt hours which is the equivalent of 3.7 gallons of gasoline. Because hydrogen is such a light and sneaky slippery little bugger even at the extremely compressed volumes it isn't much heavier than air. Thus a whole delivery truck will want to float and weigh almost the same after the delivery than it did fully loaded. What isn't calculated in the weight of the fuel that you quote is the 50 gallon tank they are using. 5000 psi is the equivalent of being 2.25 miles under the sea. So the tank has to be very strong, I'm curious to know how much it weighs. Here is a compressor with specs http://catalog.sauerusa.com/item/al...compressors-up-to-6000-psi/item-1019?&seo=110

Cheers,
Jasper
 
paultrafalgar said:
IIRC buried in here:
http://www.youtube.com/watch?v=eSevs_uAuQw Evaluating Energy Solutions to Climate Change
somewhere is information about hydrogen usefulness as a power storage medium. It's one of those interesting Stanford university lectures. It's 50-60 minutes (IIRC) long, so only watch it if you're interested in the subject generally. IIRC the conclusion was not to use H2.
Click to expand...

The conclusion was that the operating energy for Hydrogen Fuel cells would be greater than BEVs due to the difference in efficiency. However, the lecturer obviously disregards "cost" including the cost of the electric vehicles to provide acceptable long term ranges compared to other technologies, and in doing so, disregards the energy cost of extracting and manufacturing batteries. Now, if the energy ROI of batteries significantly improved and long-term ranges would be economical, then it would be compelling but it just isn't for now and probably not the relatively near-term. (Come on eestor, hurry up)
 
Hi: I am very interested in hydrogen as a carrier. there is a drone company doing an r/c sized hydrogen system. 5 hour flight time? same wieght as lipo? aeromotion or something like that -- US based. With a small fuel cell, lipo booster and compressed storage, could be feasable on small EV.

For on board-storage how about Sodium borohydride? I have worked with this substance seems pretty innoculous......

Hydrogen with renewables eg solar, hydro, wind, photo-catalytic water splitting (my personal favorite!) is the best case scenerio for future energy (barring tesla type trasmission)

Cheers
mike
 
Although H2/air will ignite easily in a very wide ratio, you would want the best-power/lowest emissions from stoich, which from link provided by jsplifer is 30% H2, to 70% air.

"...Since hydrogen is a gaseous fuel at ambient conditions it displaces more of the combustion chamber than a liquid fuel. Consequently less of the combustion chamber can be occupied by air. At stoichiometric conditions, hydrogen displaces about 30% of the combustion chamber..."

Mazda made a dual-fuel wankel turbo rotary engine. Since a Wankel has an exhaust port rather than an exhaust valve, they could tolerate a hotter combustion chamber without pre-igniting the H2. It was suggested that the engine could run on cleaner H2 when on short commutes near the H2 supply stations, but when away from existing H2 resupply stations, it would run on gasoline.

Bigmoose, I hadn't heard about using H2 as an ignition enhancer in lean-burn gasioline engines, thats fascinating and clever! With a cold winter here, I wonder if bleeding some H2 into my intake on cold start-up might make starting more sure. The current method is a short squirt of ether into the air filter. Just bought a coolant heater, need to install it...

Any hydrocarbon can be reformed (have its H2 stripped off to use in a PEM fuel cell). Gasoline has 8 carbons, propane has 3, and methanol has 1 carbon. The shorter the chain, the lower a temperature is needed to reform it. As it stands now, it appears the best range/cost fuel for a PEM fuel cell is methanol with an on-board reformer.

IMHO, the most "doable" alternative fuel is burning vegetable oil in a diesel (WVO). My dream vehicle is a plug-in diesel/electric hybrid. I only need a 15-mile range on the batteries to live 95% ICE-free . The VW diesel Golf gets 50-MPG, and the 2-seat Kinetics MAX gets 80-MPG from an 1100cc Kubota turbo diesel. Use old french-fry oil around town, and regular diesel when crossing the country...
 
It seems like there's a lot of promise in fuel cells from what I've seen. The total system efficiency of a fuel-cell + electric motor looks like it might be more efficient than a hydrogen combustion engine. However, I don't know if fuel cells have "cycle life" or other forms of lifespan similar to batteries which would be a major disadvantage if they're similarly costly to batteries.

Here's one real fuel-cell in the field...

[youtube]buNjfuVicyo[/youtube]

They state the fuel cell can produce 6 kW, has a 100 mile range, and looks to be the size of a suitcase. It looks like 10kw and a 500 mile range might take 5-8 suitcase sizes(Or, being more pessimistic, maybe 12-16. Still sounds doable for a vehicle). They also state this motorcycle has a predicted cost of $6000 which sounds pretty attractive compared to battery electric vehicles with similar specs. Although, that depends on lifespan predictions of the fuel cell.

They state the cost which seems similar, if not a little more expensive, than gas (4 dollars per 100 miles on this motorbike. An equivalent motorbike would get 60 mpg(?) and would consume 1.6 gallons ~ $4?). I wonder if the hydrogen cost cited is generated directly from oil sources, as I've heard oil-generated hydrogen is the cheapest. If so, then I guess this form of hydrogen would be indexed to the same thing gas is indexed to(oil) which really wouldn't be "clean"(Though, I'm more concerned about pollution as it affects others in the vicinity/city/highway as opposed to generation in remote relatively uninhabited areas) and wouldn't escape the tyranny of erratic oil prices, until electrolysis became cheaper.

edit: I guess I'm more concerned about calendar life of the fuel cell instead of cycle life. I think the battery could cover the majority of my cycle needs in the local area which should permit a minimum lifecycle cost, while the hydrogen fuel cell would be retained for the infrequent cross-country or longer distance trips. So, even if the hydrogen was more expensive than gasoline (Assuming not significantly so), it'd still be cheaper in the long run when the long trips consist of merely 15-30% of my total travels.
 
swbluto said:
I'm really thinking along the lines of a highway-speed, long-distance capable three-wheeler. While one may need 10 kW to sustain 60-70 mph, I'm thinking that a large enough energy capacity hydrogen system to sustain a reasonable 300 to 500 miles a day should be able to easily sustain 60-70.
Click to expand...

I.M.H.O. I think you'd be better off drastically cutting into the cruse power to maintain 65mph of your three wheeler and sticking with batteries. Case in point, recent solar racers. http://en.wikipedia.org/wiki/Nuna_2 1650 watts to maintain 100kph (~62mph). At a power consumption that low a 17KWh battery pack will give a TEN hour endurance. (around 1000km or ~600miles) Btw the Nuna 2 already carries 5KWh of lithium, or about a 300km range on battery alone.

While optimizing to the same level as the winning solar teams may not be practical, I don't think 3000 watts at 100kph is an unreasonable goal for a small 2-seat trike.

Lawson
 
What happened to hydrogen? I still think this is where we could be in ten years? Just read a great hydrogen article here to update myself with the numbers. Seem forward looking? If true these could be great "batteries" for our bikes. Also easy to store in a tank at home??


http://www.fuelcellpower.co.uk/content/images/articles/FCP%20summer%20270810b%20JA%20%282%29.pdf

Acta bike station on page ten seems pretty feasible!!

I think bigmoose is a little pessimistic here. there are always renewables and solar. Also storge such as reforming or ammonia, borohydride?

bigmoose says eairler in the thread:

"..... it has to come from somewhere. If you burn fossil fuels at the power plant it is a non starter. If you strip it from natural gas, that is fine for the amounts NASA uses, but not for powering our country. So right now the only appropriate source is electrolysis downstream of a nuclear reactor......"

well around here we have a thing called hydro!!!

any thoughts?

mike
 
Big moose has an impressive CV but this guy does as well and he doesn't seem to agree:
http://www.britannica.com/blogs/2010/7/dennis-bushnell-nasas-chief-scientist-on-conquering-climate-change
"Nuclear power could play a larger role if we were able to go to nuclear reactors that generate more fissile material than they use (also called breeders) and switch from uranium to thorium, which is three times as abundant but otherwise is probably not a major portion of the energetics solution space. Renewables remain the less-costly option."
 
This (which is posted already somewhere here):
http://www.engadget.com/2010/10/27/dbm-energys-electric-audi-a2-completes-record-setting-372-mile/
would suggest that batteries can be good enough not to necessitate going the hydrogen route. However, some hydrogen storage (beit as hydrogen, ammonia, amminex or whatever) I think has a role to play at the wind-generator for load smoothing.
 
Paul, perhaps I missed the disparity with Bushnell, he is a sharp guy. The quoted article is an upbeat sampler of just about everything that is on the horizon.

That said, I am a big supporter of the Thorium fission cycle. It is the baseline of India's nuclear power reactors. I believe the future of fission is there. DOE seems to be neglecting it for the past 10 or 15 years for some reason. I don't believe the breeder cycle will return because the byproducts are proliferable, and the thorium cycle's are not.

My reservations on solid oxide fuel cells are only related to transportation, and non steady state. They are very good at fixed installations. In fact the "mystery technology" on this thread I opine is a solid oxide fuel cell, and it appears to be doing quite well.
http://endless-sphere.com/forums/viewtopic.php?f=14&t=22669&p=330002&hilit=solid+oxide+fuel#p330002

If I missed something, let me know! That's what I love about non-politicized science, we can observe, measure and test; then draw conclusions; and debate what we think we saw and what we think will be with colleagues. The end product is we all get smarter, sharper and more perceptive as we as open minded colleagues, sharpen each other!
 
Bigmoose,

Does that mean a nuclear powered car, that I was promised as a kid to have by now still has a shot at reality (however small a shot)? How about nano nuclear reactor as a hot new buzz term? :mrgreen:

John
 
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