I also find the Ovonics fuel cell very interesting, essentially a NiMH battery adapted to pump H2 into the cells to supplement the H2 normally stored in it when operating as a battery. Uses no platinum catalyst. Tested to -20 deg. so far. Eliminates the 2 min. startup time of PEM's and can recover, store and return the regen braking energy in the fuel cell. Very rational at first view. http://ovonic.com/sol_srv/3_2_fuel_cell_sol/fuel_cel_solutions.htm

Ideal cycle for efficiency, however, is still the boron / oxygen engine.

Roger - I admit I largely buy the RMI "koolaid", but not without reason. The Prius is already a large part of the technology. Lotus has built lightweight fiber composite cars for years and sold them affordably (albeit expensively) even with hand layup. The only thing keeping carbon fibre cost high is lack of really high volume production. Mazda has a new Miata concept car almost ready to roll out with a carbon fibre composite body shell. Daihatsu had a concept car at the Jan. 2004 Tokyo motor show with a light weight body, hybrid drive, and claimed 140 mpg. Even though the starting raw material for a fibre composite body is much more expensive than sheet steel today, by the time the steel is cut, formed, cleaned, welded, and painted the body shell cost is pretty close to a fibre composite body with the color baked in, and the capital cost for the fibre composite body is much less than for the steel one. RMI has had their projections validated both by retired American auto engineers and by Lotus engineering. The big obstacles are entrenched thinking of current auto engineers and managers, who are a very conservative bunch, and the existing capital sunk cost. When the Japanese start selling the next generation lightweight hybrids in the USA, and the waiting lists are again long, Detroit again will reluctantly move in the right direction. It will probably take at least another 10 years, but the hand writing is on the wall. Murray

Repeated references to "hydrolysis", meaning splitting of water, are grating. Things that dissolve irreversibly in water are hydrolysed, i.e. broken by water. Breaking of water is beyond the range of meanings that word can usefully have. "Water-splitting" is a good expression to use, or if by electricity, water electrolysis.

I agree Bossel and Eliasson are too dismissive of liquid hydrogen, in effect knocking over a compressed-gaseous-hydrogen strawman. This is obviously a hazardous procedure!

Over the years many hydrogen cars have existed in the lab (cf. the hydrogen car timeline) and, to the best of my knowledge, no aluminum-burning ones.

But that just means aluminum-burning cars in real-world service are equally numerous with hydrogen cars so serving. Aluminum would be lighter and safer, and already is produced on a large scale using renewable energy.

--- Graham Cowan, former hydrogen fan
Boron: A Better Energy Carrier than Hydrogen?

Bob Hoffman Energy Dynamix Corporation

Of course, you auto engineers may know some secret reason why it is better to leave development of solutions to future problems to the Japanese or Europeans (or Chinese).

"We've shown that hydrogen can be produced at temperatures and pressures suitable for a Generation IV reactor," said lead INEEL researcher Steve Herring. "The simple and modular approach we've taken with our research partners produces either hydrogen or electricity, and most notable of all achieves the highest-known production rate of hydrogen by high-temperature electrolysis."

On re-reading, it appears they may not have actually progressed as far as I'd thought. Still, getting there.

Thanks GRL Cowan at Boron Blast - Boron a Better Energy Carrier for tips on posting links.

And I still think the boron / oxygen cycle engine beats hydrogen.

The methane retains 80% of the original energy content of the 4 hydrogen molecules. Compared with the efficiency of electrolysis, this is a greater improvement in energy density for the energy expended, so it should definitely be done if the CO2 is available. A two-pipe system of CH4/CO2 (moving in opposite directions) moves energy more efficiently than a single pipeline of H2 because the molecule count is reduced by 50%, but the energy stored is reduced by only 20%. Because the gas behavior is dominated by particle count, not weight (remember PV = nRT ?), the heavier system of CH4/CO2 still takes less energy to move than the bulky H2.

There is plenty of CO2 for now, and more will be available later. Biofuel production alone produces enough byproduct CO2 (that is easily captured and carbon-neutral) to support millions of methane-driven vehicles. We just need the hydrogen. In the future, all the pure O2 that is a by-product of electrolysis can be used to facilitate CO2 capture at stationary plants (I can explain that more if anyone is curious).

The reason this will supplant any effort to building a pure H2 economy are threefold: infrastructure is already in place, the medium is 3.2 times denser energetically than H2, the system can co-exist with natural gas supplies.

H2 is a horrible fuel medium for vehicles. Even if a FC was 100% efficient (LHV), the storage requirements for hydrogen vs. methane would still be larger, even if the methane is burned in an engine that is only 33% efficient (LHV). So, all things being equal, a FC car will have less volume available to the customer. Efficiency improvements for vehicles are far more effectively accomplished with plug-in hybrids, which bypass the whole fuel creation issue entirely. Since a plug-in still has fuel powering it also (and thus range), it shares virtually all the benefits of an all-electric vehicle (including energy efficiency) with none of the drawbacks. All an automaker needs to build is a plug-in hybrid that can run on methane. Heck, maybe a small gas tank too. That's it. No fuel cells. No hydrogen. No infrastructure changeover.

At the risk of sounding patronizing, the problem with energy studies is that if just one piece of information is out of place, one needs to rewrite a whole strategy. Such is the case with hydrogen. If energy storage via carbon is the best strategy based on billions of years of evolution, who are we to question it? The answer seems clear to me (unless, of course, I've missed a piece of information).

-Jim

Arguing from the authority of Nature will, if done consistently, take you some places you probably don't want to go.

--- Graham Cowan, former hydrogen fan
Boron: A Better Energy Carrier than Hydrogen?

Regarding infrastructure, the two pipelines would not need to be set up extensively in practice, only in a few select areas. As an example, consider the wind resource of the Dakotas, a good potential energy source for hydrogen production and which would be expensive to access via the electrical grid. If this hydrogen source was fed CO2 produced from biofuel plants located around and near that area, then only a few hundred miles of CO2 pipeline is needed. The existing NG infrastructure could pipe the produced methane out of that area to points west, east and south.

By your own calculations, FCs net 18% more efficency than methane if plug-in hybrids can be employed. But you need to be careful to base both systems on HHV, not LHV. The LHV for hydrogen is only about 82% of its HHV, compared with about 90% for methane (LHV/HHV). So if you are assuming 90% (LHV) efficiency on your fuel cells, this would translate into 74% (HHV). If I am following your calculations correctly, this puts the net efficiency of the FC back to 50% (instead of 60%) and lowers the combined efficiency to 75%. On the other hand, SOFCs (burning methane) could bring the methane vehicle up to 40% (HHV), for a combined efficiency of 72%. So this whole hydrogen infrastructure may only net us 3% more efficiency for our vehicles, certainly not the 2-3X efficiency improvement that some are claiming. I know Bossel-Eliasson rattled some cages, but their comments on the LHV/HHV issue are very important.

I understand this seems to be placing a burden on getting plug-in hybrids to work, but given the market introduction of regular hybrids, this seems a more likely bet than the near-term introduction of fuel cell vehicles. As an aside, the recent NAS study on hydrogen vehicles completely omitted plug-in hybrids entirely. I cite this as evidence of how dynamic this area is at present.

Finally, there is probably enough carbon-neutral CO2 to go around. There is potentially 15 quads of biomass available in the U.S., by some estimates. Only about 3 is used now, so let's assume we could get to 7 quads, just to be safe. If used to produce biofuel, that would produce 7 quads of fuel plus enough CO2 to support 7 more quads of methane. Probably enough to go around. Plug-in hybrids would help with this, as they would reduce the amount of energy (as fuel) needed by our vehicles.

Thanks for the discussion! I'd much rather be shown to be wrong than to remain wrong-thinking, so I think it's important to keep interrogating each other until we can figure this all out.

-Jim

I think this was in the news a year ago. I don't recall just where the methane was supposed to get burned, but if it was in cars, there are some details that were, as far as I recall, only implied. I fill them in thus: to get back to the Sabatier reactor, carbon dioxide from a combustor exhaust port (through which it passes in fairly dilute form) is cooled to a temperature very near ambient, so cool that perhaps liquid CO2 condensation is possible (temperature well below the critical one of IIRC 31 Celsius). That would allow some degree of separation from nitrogen.

Kept in an onboard tank, the CO2 can be swapped for methane at a refuelling point, and from there travel through the return pipeline to the power station.

There are already a few thousand cars with compressed methane tanks. How would the onboard CO2 tanks compare in volume? I may get around to this arithmetic if no-one else does.

--- Graham Cowan, former hydrogen fan
Boron: A Better Energy Carrier than Hydrogen?
Everyone knows the one true answer. Maybe they can agree this is the second choice?

Regarding electric-based grid distribution of hydrogen -- that's fine, assuming the grid is always going. But if we wish to move to more renewable electricity, the grid may NOT always be going, at least to the extent needed to support vehicle fuel in addition to our electrical needs. If that's the case, you either need electrical storage or massive bulk hydrogen storage to accommodate the daily and even seasonal variation in our renewable energy sources. We obviously get more sunlight during the summer months, so if we wish to take advantage of this resource, we need some way to store it. Not for hours or a few days, but months. Since electrical storage (batteries) would be far too expensive, that leaves hydrogen gas, and a lot of it, much more than you could store at individual gas stations. Given that, finding, and perhaps moving a bit of CO2 is not so bad, because it would reduce THAT storage by a factor of 3 as well.

-Jim

Regarding Dursun Sakarya's comment, of course making hydrogen (from electricity) is a net energy sink. It always will be. It will NEVER be an energy source, only a medium.

The point is STORAGE and TIME. If you want to use energy that was accumulated in the past, you need some way to store it. Hydrogen (or methane) is a convenient way to store energy, at least compared with electrical charge, or even chemical batteries.

This convenience comes at a price. Only 70 or 90 percent (or whatever) of the electrical energy remains in the hydrogen. But the storage cost is much lower, so depending on how long you need to be able to store the energy indicates how wise it is to create the hydrogen in the first place.

People seem to have no trouble understanding that a laptop computer should cost more money than a desktop computer of equal capability. With energy, the situation is the same. Higher density is more convenient and thus more valuable. Under the right conditions, making hydrogen from electricity can be a value adding operation.

-Jim

Discussing whether bi-directional methane/CO2 systems make sense in terms of the energy distribution infrastructure of today or the next twenty years is fairly pointless, it won't happen on a widespread basis. In 200 years? Who knows, maybe. But given todays pace of scientific development and extrapolating that far, I'd guess it's simply an academic exercise. Chances are that by then any energy requirement you can't collect from the globally available harmless microwaves beamed down from power satellites designed to mitigate the onset of the next ice age, can be gotten from your pocket fusion reactor / garbage recycler as necessary.

It's like asking George Washington to predict the optimum energy distribution infrastructure for powering the computers and cellphones of 2005, though even that understates the likely level of change given todays rate of communication and organization in scientific and technological research.

One thing that is fairly predictable is a large penalty for allowing carbon atoms to combine with oxygen. The way carbon nanotube developments are heading, i'd guess by then pretty much everything from your personal transporter to your 3D video display will be manufactured largely from pure carbon. Hopefully the price of the nanotube can be brought down for current $85,000 / kg.

Since methane and methanol are equally suitable as fuel for an IC engine, or for reforming and fueling a high temperature SOFC, my question for Jim is why advocate methane rather than methanol?

Maybe we don't need CO2 (or hydrogen) pipelines at all. Maybe plug-in hybrids are enough and we can just use foreign oil for the remainder.

Maybe global warming is worse than we thought and we can't even do that.

Maybe plug-in hybrids won't work, so producing fuel from renewables IS important after all.

Who knows? But I think it is important to at least try to think some of these things through. If only to keep politicians from wasting more of our money.

But I do know that even if we do have fusion reactors or solar power satellites, we will still desire a dense, energetic fuel for some uses. But maybe by then, we'll have enough energy to just make JP-8 and be done with it ! :)

-Jim

It is kind of a crummy fuel though, about twice as bulky as gasoline, very poisonous, hard to keep the NOx and formaldehyde emissions down. I'm not saying it's liquid form doesn't trump these concerns, but I think there may be a reason why it hasn't been enthusiastically embraced to date.

If I remember correctly, converting from methane -> methanol or methanol -> methane both leave about 80% of the energy left over, so if you ARE making it from scratch it would be beneficial to figure out which one you want and to stick with it. Since our existing infrastructure does have some high efficiency combined-cycle gas turbines (58% efficient), there is probably a use for at least some methane. The obvious convenience of a liquid fuel can't be overlooked, however. I'm not (yet) impressed with methanol fuel cells -- a recent vehicle demonstration in Germany could only produce about 1.5 kwatts.

On the other hand, it is possible that with liquid fuels, there is no free lunch, and you are paying even for that. For example, consider ethanol vs. methane as a fuel product from biomass. Ethanol, being liquid, is obviously a more convenient fuel. But the fermenting process produces ethanol in a water mixture, so a drying step is needed, which can be up to 30% of the energy content of the fuel produced. If this step can't be improved, or perhaps implemented with a waste heat source, then the "cost" of this convenience (the fuel being a liquid) could be another 30% of energy needed. Based on that, a pressurized tank might pay for itself in a just hundred fillups or so. Methane, on the other hand, is more easily separated (energetically) CO2 if the biomass is subjected to methanogenesis by methanogens instead of fermentation by yeasts. Only about 5-10% of the energy content is needed for the separation of methane from CO2. There may be some issues with methanol in the same way, but I'm not sure. (I'm not 100% sure of this "liquid-fuels-are-not-a-free-lunch" thing, just a hypothesis....)

I think in general, if we can understand how to live with smaller chain hydrocarbon fuels, at least in theory, we will be less surprised if oil depletion accelerates in the future and forces our hand.

(probably talking too much......)

-Jim

Do you have any opinion about the ZECA approach to gasification? It starts out by "burning" any carbon or hydrocarbon fuel in a hot hydrogen atmosphere to produce methane. The methane is then reformed with CaO and water, producing CaCO3 and at least twice as much hydrogen as used to make the methane. The CaCO3 is then calcined to regenerate CaO and a pure stream of CO2.

What's interesting to me about that process is that it should work well with oil shale as the hydrocarbon input. We have lots of that around. If we combined it with electrolytically generated hydrogen from renewable sources, it would stretch pretty far.

It seems like there's a wealth of good possibilities. Fighting wars over dwindling oil supplies is criminally stupid.

From what I can figure out, methanol is not nearly as bad as MTBE, because it does decay naturally and quickly in the enivronment, but it is not all that wonderful either. If your toddler drank a tablespoon of gasoline, she would get sick. But if it was methanol, she would either die or have permanent serious injury. Methanol in higher concentrations also does NOT break down naturally because it kills the microbes that would normally feed on it.

We also DO have the existing NG infrastructure. I just tore the old oil tank out of my basement, so it would be annoying if they decided to heat homes with methanol instead. :)

-Jim

According to their own website, the ZECA system does not produce hydrogen that is pure enough to be used in PEM fuel cells without degrading their catalysts. Ridiculous! Using hydrogen is IC engine is the worst of all worlds : poor fuel density, poor efficiency, they even have no-so-great NOx emissions.

In general, the notion of hydrogenating to remove C-C and C-O bonds from a hydrocarbon is a good idea. It improves the ratio of energy/CO2 produced from combustion. In terms of what ZECA is doing on both the methane production side and the CO2 capture side, I'm not sure how efficient they really are. Both seem to require substantial heat input, which has to come from somewhere.

I'm more of a fan of hydrogenating biomass, because you still get a good fuel (methane, methanol, perhaps even a kind of biodiesel) and the result is carbon neutral. The ZECA system is a little vague about how the CO2 sequestering is going to work.

I think we really need to be honest with ourselves and put all our cards on the table.

Are we considering the move to hydrogen because of the concern about oil depletion or global warming?

If it is oil depletion, then we should look to fuels from biomass or coal, such as methane, methanol, and biodiesel (we probably can't make a LOT of this stuff). We should look at improving efficiency with hybrids and plug-in hybrids. If we can reduce our oil use by just 10% (with a glare that we can reduce it another 10%) that would send enough shocks to the supply side of the oil industry to settle things down for another 20 years or so. But no hydrogen is needed in this equation. As for our electrical needs, just keep building coal plants.

If it is global warming we are concerned about, we need to limit emissions from our coal plants. Vehicle CO2 emissions are a small part of the equation, and not the thing to be looking at. We need to figure out how to integrate renewable electric in our grid and build more infrastructure for this. At least enough to forgo additional coal plant construction (This is the Joe Romm belief.) We need to consider nuclear power again, and gauge the risk/reward of that versus global wamring. We need to conserve electricity. There is probably at least 10-20% hardship-free reductions in electrical consumption that could be instituted if we focused on this. It is mostly an educational effort, as a home or business is always interested in saving money on their power bills. Again, no hydrogen here either.

In my opinion, the best, safest, and cheapest method of carbon sequestration is to burn less coal, and leave the solid chunks of near 90% carbon in the ground.

Given that the fossil carbons still wind up being dumped, and methane itself is a far more worrisome GHG than CO2, I just don't see the balancing benefit.

I agree with Murray that coal won't last as long as people think, especially if it is used more aggressively. With respect to a fuel, you are better off just making methane from coal, and using that. Assuming you sequester the CO2 from the methane production process (NOT during the methan USE) you still save about half the CO2 that the coal would otherwise produce. You could replace that CO2 emitted (from the methane use) by sequestering a like amount of CO2 obtained from biofuel production. The potential for biofuel from cellulose is hopeful, and since the process produces much carbon-neutral CO2 as well, biofuel production can serve to utilize fossil fuels in a carbon neutral way further. Assuming large scale CO2 sequestering works. I'm a little skeptical about that. If you have one wellhead split open, you could kill a few thousand people downwind with a CO2 leak. That would give CO2 sequestering all the public confidence of a nuclear power plant.

I realize proposing to turn our cars over to NG sounds crazy, given our current shortage. But we have more NG around than we do hydrogen, which doesn't exist at all, and which is most commonly obtained from NG in the first place.

I'm trying to figure out what the two leaps are. I think the first is domestic energy independence, and the second is no carbon emissions. Is that close?

Electrical grids are not cheap, are only really economically practical for lengths under 300 miles or so, and depend on 24/7 use. We tried to size a grid needed to get the wind power from the Dakotas to Chicago. It's really hard. You either end up throwing away a bunch of electricity during peak times, or way oversizing the wires, making the transport of electricity ridiculously expensive. Another thing that people don't seem to understand is that renewable energy is completely different than our current system. Fundamentally so. Not necessarily worse, just different. It has to do with their intermittent nature, which is totally anti-thetical to the grid as we presently perceive it. But if we can learn to live with this, our ability to integrate these resources will be much easier for us.

Methane is not that much worse than CO2 as a GHG. True, it is much more heat absorbing, but it break s down (into CO2) after about 10 years. So over the life of the molecule, CH4 is only about 5X worse than CO2, not the 20X that people say. (That was another thing CARB got wrong.) Since CH4 is useful, presumably people will work harder to capture and use it rather than let it drift away.

I think a good experiment would be to develop some of the wind resources in the Mid-Central states. Use the energy to make hydrogen and then methane and probably some ammonia too. (Ammonia is the lowest hanging fruit for electrolyzed hydrogen, and producing it would reduce some of the methane use from that industry.) The CO2 is fed from nearby ethanol plants. (I'm not a huge fan of corn-based ethanol, but they are good sites to test out the process.) Congress just approved a massive NG pipeline to come down from Alaska, so the system could pipe into that. Depending on how much wind we capture, we'd end up producing a centrally-located, but very disperse methane source that would never run out. All of this would cost money, of course, but since so little gas would be initially produced, the overall price of NG would not go up very much.

In the short term, we need to conserve energy more and add smaller renewable energy sources locally that people can use. Plug-in hybrids are good for this because they can be plugged in perhaps 20 hours per day, so they have a good chance of getting charged from an intermittent source. We need to resist the urge to build more coal plants, because that's a 50 year committment of infrastructure to emit more CO2.

If our government is working to make us safer, it is hard for me to understand how spending another dollar on defense accomplishes this, versus spending that dollar on either increasing domestic energy production or increasing our energy efficiency.

-Jim

Your statement "electrical grids are not cheap... " etc just doesn't hold up. Compared to what? Anf you guys need to stop evaluating AC electrical as the only possibility (300 miles). HVDC at modern voltages can transport energy more economically than rail or pipeline and the greater the distance the greater the advantage. With articles such as F. Mack Shelor's at The Arguments for a National Direct Current Transmission Grid , or the proposal for a continental DC grid by Black and Veatch, and many others having been around for years, there is simply no further excuse for not fianlly bringing the grid into the 21st century and resolving all these issues. Or see my own proposal, the Active Electrical Transmission System

The limits of North-South NG transmission are already filled by Canadian production so building the pipeline from Alaska proposed by congress (only to the canada border) will either require an additional huge investment to get the gas from the Alaska-Yukon border into the markets or displacement of currently available production. Neither makes sense. This one should be held off until canadian production has fallen enough to allow it to use existing pipes. Problem is, that would require some creativity in how to expand energy production in the mean time. BTW, Canadian NG resources fell almost 5% last year despite record drilling.

I am suggesting electrical grids are not cheap compared with pipelines. I am not suggesting to make a fuel from electricity, pipe it somewhere, and then convert it back to electricity in a power plant. That wouldn't be wise. What I am suggesting is that some electrical power could be 'stranded' which might be better off converted to some kind of fuel instead. And then use the fuel in a vehicle.

The problem with any type of electrical transmission grid (AC or DC) is that electricity can't be stored in it. A pipeline can accommodate different pressures to allow for some storage as well as storage in geologic structures, etc. If we wish to embrace renewable electric (sun, wind) then we need to think about the grid more carefully. The grid at present relies on flexible capacity to match demand changes. If the future grid is to accommodate renewable electric, it will have both the supply AND demand sides changing somewhat randomly. I don't think they are prepared for that. That's why utilies are reluctant to assign wind farms any percentage of base capacity. This is a much more serious problem than whether we should have DC vs AC transmission lines, in my opinion.

It may make sense for some amount of the power to come out of the Dakotas as electricity, but it would have to be a small percentage of the peak power production, well under 30%, I would think. Otherwise the transmission capacity would be wasted.

I thought they had approved funding for the entire pipeline, not just that section. My mistake.

Jim, believe me the entire NG pipeline network can't vary the pressure enough from min to max ro make much difference in storage. It might be 1% of annual consumption. You havent read the paper I published on wind. Intermittancy is not a problem in a geographically large well integrated grid, with modest back up storage. The storage can be hydrogen, or pumped hydro where that is possible. yeah, I am all for hybrids, and for plug in hybrids if batteries are not problematic (which I am not yet convinced of). Hybrids are a very important bridge to the HE as I thought I made clear in my paper. Murray