The Ergosphere
Sunday, July 24, 2005
 

The money-grubbing mendacity of the ethanol lobby

Note 15-October-2006:  If you came here via a Google search for "ethanol lobby", you probably want to read this concise summary of the issue before digging through this post.  You can always come back later.

This is annoying.  I've got two posts being editted (one on hydrogen, one to continue the analysis of the possibilities of a zinc economy) and distractions keep getting in the way.  Fortunately, I'm getting a post out of this one.

Recently, a mail from a very sincere but not terribly logical ethanol advocate was forwarded to me by James at Alternative Energy Blog.  I picked apart some of the questionable claims and did a short analysis which showed that bio-fuels cannot possibly replace petroleum (quoted directly from my mail, lightly reformatted for the web):
Executive summary:
  • Ethanol as currently made (from corn) is a loser.
  • Biomass sources are insufficient to replace petroleum directly.
  • Waste biomass can be a useful source of supplemental fuel and other chemicals, but most energy has to come from  something else.
  • The biggest advantages come from leveraging new energy sources and boosting efficiency, which can be done in very un-obvious ways.
[deletia]

Yes, you can derive energy from waste.  No, you cannot use this to replace more than a small fraction of coal, oil and natural gas. To the extent that the waste contains energy derived from fossil fuels, the net benefit is even smaller.

...

[referencing Going negative] I was talking about biomass as a source of CARBON, with most of the energy coming via a more direct route (from sunlight).  You could have proven this to yourself with a little arithmetic, which would have shown that 600 million tons of biomass per year is nowhere near enough to replace US use of petroleum.

Let's work it out just for show.  Let's assume that all the biomass is carbohydrate, with a general formula of CH2O.  If you converted the full 600 million tons to hydrocarbons by magical removal of the oxygen without adding more energy or losing any of the rest (impossible, but assume it for the sake of argument) this 600 million tons of biomass would make about 280 million tons/yr of syn-oil, or about 770 thousand tons per day.  Figuring this as short tons and the density of the syn-oil at 0.8, that makes 873 thousand cubic meters of syn-oil per day or 5.5 million barrels.  (Remember, this is with a process of impossible efficiency.)

US oil consumption is approximately 20 million barrels/day, and then there's natural gas and coal.  Even if you could manage this feat of removing oxygen from biomass and converting the carbon and hydrogen to syn-oil without losing any of it, you'd only replace about 27% of US petroleum consumption.  You wouldn't even cut imports in half, and you wouldn't displace anything else.

What you missed ... is that you can get a lot more out of the resource using a couple of levers to multiply the benefits from the inputs.  In my blog example, the two levers are:
  1. Using carbon from biomass to make a *solar* process much more efficient.  Much of the new energy comes from the sunlight, not the carbon feed.  (At least, that's what the Swiss are claiming they've done.)
  2. Getting the energy *out* in the form of metallic zinc, which can be used in a zinc-air battery instead of a combustion engine.  The Zn-air  battery is far more efficient than an engine and yields much more useful energy out per unit of input.  It's like getting a new type of car engine that's 80% efficient instead of 20%.
Combine those two multipliers, and you go from a replacement for 27% of US crude use to replacing ALL motor fuel (roughly equal to US oil imports) and something like half of the coal-fired electricity too.

[correspondent notes that THERE's a surprise is very down on ethanol and asks if I was being sarcastic in one piece or the other]

I was being completely serious both times.  The devil really and truly is in the details, and you've got to know your chemistry and physics to avoid getting completely lost.  The laws of physics and thermodynamics are uncompromising and will break any attack you can throw at them without yielding, but you can sometimes find paths of lesser resistance which go around them like jiu-jitsu.  "Nature, to be commanded, must be obeyed."

The problem with current corn-growser subsidy programs, excuse me, alcohol fuel programs, is that they attack Nature head-on.  This is why they need something like 3 BTU of fossil fuel inputs to get 4 BTU of alcohol out. Don't you agree that such wastefulness really is worthless?
Apparently not.  The response was a list of enterprises making fuel ethanol, and their annual production.  I replied that they were probably in it for the subsidy money.  This attracted a fairly long and marginally literate screed, from which I shall paraphrase the author's remarks to avoid quoting without permission.
[subsidies are not to get people to make alcohol]

They aren't?  There's a 52 cent/gallon federal subsidy for ethanol used in gasohol (5.2 cents/gallon tax charged to 100% gasoline but not 90% gasoline/10% ethanol).  Subsidies to the growers are in addition to subsidies for the fuel blenders.

[correspondent knows because correspondent is a farmer]

I was going to go into your reply to my analysis and ask you why you had no rebuttal to the facts I cited - facts which prove that what you desire is IMPOSSIBLE - but you just explained everything in 4 words:

"I am a farmer"

That shows where your interests are.  It is actually BETTER FOR YOU if ethanol cannot fully satisfy demand, because this means that you can never wind up with the oversupply problem that exists now.

Here, I'll prove it.  Look at the 2004 USDA harvest figures for corn:
http://www.usda.gov/nass/graphics/county04/data/cr04.csv
I summed up the state by state figures and came up with 11.8 billion bushels total harvest.  At a conversion rate of 2.66 gallons per bushel (per http://www.ethanol-gec.org/corn_eth.htm), you would only get 31.4 billion gallons if *all* of it was converted to ethanol.

Total US motor gasoline consumption in 2003 was 134 billion gallons.  (http://www.eia.doe.gov/emeu/aer/txt/ptb0513c.html).  And given that each gallon of ethanol requires roughly 3/4 of a gallon-equivalent of fossil fuel (including about about 0.44 gallon-equivalent of natural gas, according to http://www.cvec.com/general_manager.htm), the net gain is perhaps 8 billion gallons-worth.  That's a lousy 6%.

In short:  farmers will NEVER solve this problem, because it is PHYSICALLY IMPOSSIBLE.  Worse, farmers DO NOT WANT THE PROBLEM SOLVED because if supply catches up with demand they wind up with the same unprofitable crop prices they have now.

Conclusion:  FARMERS BENEFIT FROM PUSHING A "SOLUTION" THAT CANNOT WORK.

[correspondent know what farmers are and are not getting paid for]

I know what fixes your personal problem as a farmer.  I know that this will never fix the problems faced by the nation as a whole.

[correspondent includes article titled "Claims that Ethanol has a Negative Energy Balance are Outrageous"]

So what?  Even if ethanol from corn required NO fuel for planting, tillage and harvest, NO fertilizer and NO distilling, it would STILL never come close to replacing petroleum.  And you want it that way.
That's it, folks.  The ethanol lobby is as foul a pile of money-grubbing liars as has ever graced Tammany Hall or the the oil-for-palaces office at the UN.  They are not even trying to solve America's energy problems, they are trying to make certain that the problem is never solved so that they can benefit from a demand that their scheme can never sate.  You can confront them with facts, and they will ignore them and continue to push programs which benefit only themselves with the lie that this is good for the nation.

These people disgust me.

Related items:
THERE's a surprise
Going negative

Labels: ,

 
Comments:
The purpose of the subsidy is not to encourage the production of ethanol; The purpose of ethanol is to provide an excuse for the subsidy. By encouraging a supposedly 'environmental' product, the politicians expanded the coalition to a point where it benefited enough people to get legislation passed.

Of course now that the subsidy is in place, the few who profit oppose any change. The many who pay, pay only a little. It's hard to get our outrage going. We know intellectually that the money is wasted, but if we change the law it'll just be wasted on something else. The farmers will have a subsidy, simply because in our democracy there are enough farmers to command a subsidy.

Paying them to make ethanol may be less harmful than some other choices. At least the farmers are being paid to do something that has a small net positive benefit. (Or am I misunderstanding?) It's a waste of money, but the money was bound to be wasted anyway. If we weren't paying them to make ethanol, we'd be paying them to make cheese; Then we'd stockpile it in caves to support the price.

Just to be clear, I'm against ethanol subsidies; Apparently I'm also feeling cynical and pessimistic today. A rational case can be made for maintaining some excess ag production capacity. Maybe the goal should be to buy that insurance as cheaply as possible, without screwing up our energy policy.
 
We had a perfectly good way of subsidizing farmers and dealing with overproduction:  we used to allow them to idle part of their land and collect a payment for the profit they would have made on the grain.

Paying subsidies on the additional crops we use to make ethanol, paying fuel subsidies on the results, and dealing with the extra soil erosion, nitrate pollution and other damage from the process has no excuse IMHO.  There may be more-harmful choices out there, but how insane do we have to be to avoid going back to the better one we once had?

Unfortunately, ADM's lobbyists have more money than sanity does.
 
I do not understand why, in the case of ethanol replacing gasoline, a partial solution should be completely discarded because it isn't a full solution. There aren't any complete solutions readily available but a temporary, partial solution that moves us toward a complete solution is better than a complete "ideal" solution that isn't likely to be available for 20 years if at all.

Brazil provides a case in point. They have a partial solution - sugar cane ethanol and flex-fuel cars - that is displacing about half of their fossil fuel demand and providing export revenues. It is also exerting downward pressure on gas prices. All new cars will be flex-fuel capable by 2007. Their government set the policy and supported it with subsidies and it paid off - big time. It took them 30 years. We can sit on our hands for another 30 years and wait for a perfect solution but I don't think any sane person expects that to pay off.

The ethanol subsidies don't just buy us a diversion from liquid fossil fuels (2% at last count) - they also help build us an infrastructure for distribution and usage, and a demand for flex-fuel vehicles and technology development. They are maturing and becoming more efficient.

Waste-to-ethanol through gasification doesn't just get us gasoline diversion - it also reduces the need for landfill, reduces greenhouse gases, and provides environmentally friendly disposal of sewage, MSW, agricultural and forestry wastes. It also co-generates green electricity. Net energy gain with no toxic wastes.

Ethanol use also gets us closer to hydrogen fuel cell alternatives since ethanol is the transport medium for delivery of hydrogen to fueling stations.

The availability of any competitive alternative to gasoline will have a dampening effect on the price of gasoline and serve notice that we finally have an alternative to dependence on foreign oil.

Farmers in the red states are helping us develop capacity and infrastructure now. Waste conversion in the blue states could provide more localized production and urban environmental improvements.

In short, I'd rather subsidize the development of a domestic renewable fuel solution than sit on my hands and continue to subsidize the Mideast conflict through sky-high gasoline prices and military interventions.
 
I also think something unexpected (for many people) is about to pop - worldwide, climates having been changing, and drought is taking its toll.

Crop yields are going down. Grain production is dropping.

This will affect the United States largely by affecting price,

but the point is, can we justify crop land for liquid fuel when people are hungry?

Humans are more efficient at turning corn into energy than ADM is. We've got guts.
 
C. Scott Miller writes:

"I do not understand why ... a partial solution should be completely discarded because it isn't a full solution."

Mostly because the "solution" costs far too much for too little, is in no way sustainable given the tightening supplies of its essential inputs, and is part of a corrupt system.

"Brazil provides a case in point."

Which is not applicable to the United States.  Land suitable for sugar cane isn't common and conditions are still so poor that cane requires import restrictions to be economic.

"We can sit on our hands for another 30 years and wait for a perfect solution but I don't think any sane person expects that to pay off."

That's what the hydrogen advocates are pushing.  I am opposed to this; I want the USA to go for one of the solutions which will get us by today (the GO-HEV) and simultaneously set the stage for evolution to whatever further development works best:  pure rechargeable electric, zinc-air fuel cell, methanol fuel cell, or maybe even hydrogen.  The GO-HEV is a waypoint in the evolution to any of these options.

"The ethanol subsidies ... help build us an infrastructure for distribution and usage, and a demand for flex-fuel vehicles and technology development."

What infrastructure?  Tankers and pipelines?  Those have been in use for over a century.  Every gasoline-burning car built in the last decade-plus can burn 10% ethanol.

Apparently you did not (cannot?) understand the points of the post:

1.  Ethanol from corn cannot satisfy demand even if the entire US crop is used.
2.  Ethanol from corn must be produced with inputs (petroleum, natural gas) which are in tight and shrinking supply.

The sole virtue of ethanol from corn is that it can be carried in standard tankers, dispensed through current pumps and used in existing vehicles.  It is far more expensive than petroleum (and will remain so since so much of its cost is from petroleum and products whose prices track petroleum, like natural gas), separates from gasoline when exposed to water (requiring special handling), and has ecological impacts extending as far as dead zones in the Gulf of Mexico.

"Ethanol use also gets us closer to hydrogen fuel cell alternatives since ethanol is the transport medium for delivery of hydrogen to fueling stations."

Wrong.  The favored medium is natural gas... which we are rapidly running out of.

"The availability of any competitive alternative to gasoline will have a dampening effect on the price of gasoline and serve notice that we finally have an alternative to dependence on foreign oil."

That's the first statement you've made which is unequivocally true.  Unfortunately for your overall case, ethanol is not that competitive alternative.

What you are looking for is electricity (compare gasoline and electricity on the basis of cost per kWh at the wheels, it is very illuminating).  We can generate electricity with things that cannot make ethanol, ranging from cogeneration for industrial process heat to the sunlight falling on your roof.

"Farmers in the red states are helping us develop capacity and infrastructure now."

Capacity which requires huge tax subsidies to operate.

"Waste conversion in the blue states could provide more localized production and urban environmental improvements."

None of that Red-state infrastructure is useful for waste conversion (you neither wet-mill garbage nor ferment it with Saccharomyces), and the farm lobbies will do what they can to prevent waste-derived ethanol from cutting into their market.  (Don't believe me?  Look what soybean and canola farmers are doing to prevent palm oil from receiving the same preferences they want.)

"I'd rather subsidize the development of a domestic renewable fuel solution...."

Ethanol from grain of any kind is:
1.  Not domestic (it requires imported petroleum and nitrates in considerable quantities),
2.  Not renewable (petroleum to cultivate, natural gas to fertilize, more gas or coal to distill, and soil erosion), and
3.  Not a solution, because scarcities of its inputs will squeeze us just the same even if we can continue to pay for the subsidies (I have my doubts).

If you want a renewable solution, look at the GO-HEV recharged with wind or solar power.  The vehicle is somewhat more expensive at this point but wind turbines and PV cells require no fertilizer, no cultivation, no agri-chemicals and cause no soil erosion.  As for displacing petroleum, each GO-HEV might cut fuel requirements by 50% or more (going up as batteries get cheaper and each car gets more of them).

Ethanol?  Ethanol is a profit center for Iowa farmers and ADM.  Let's buy out enough farmers to fix the oversupply, throw the ADM execs in jail where they belong, and put the savings someplace where they will actually fix the problem.

Monkeygrinder asks:

"can we justify crop land for liquid fuel when people are hungry?"

No, but hunger is not the justification for what's going on; it's all money-politics.
 
What if the *best* crop for ethanol production were grown, as opposed to simply the crop the farmers are accustomed to growing? In Australia the great relatively new idea is to prop up the sugar cane farmers by buying their cane for ethanol production. How dumb can you get? It seems probable that in the medium term there will be some kind of niche for ethanol - however small - so it would be wise to use the most efficient production methods. What I'm getting at is, in a word, hemp. I'm not a hemp campaigner (but I was in my own small way 10 or so years ago) and I know that its advocates claim that it's much more suitable for ethanol production than any food crop. If you have the time and the energy, engineer-poet, you should suss it out (I myself lack the required energies).
 
Hemp is an annual.  The research into cellulosic ethanol seems to be going to perennial grasses like switchgrass, which have the advantage that they hold the soil better and do not require reseeding.
 
"Ethanol from corn cannot satisfy demand even if the entire US crop is used."

Re 1., actually it could pretty much. Barry Commoner proved that back in the early 80s. Its amazing how the work of one wrong-headed scientist named David Pimentel (who also notes that petroleum is energy negative) can infect the thinking of people of all political stripe. The corn fed to chickens and animals is processed, the residue goes to the animals, the fuel is made. This not only solves the land problem but the food vs fuel debate so mindlessly promoted by wannabe experts.

Look for a new book out in the next several months called "alcohol can be a gas," written by permaculturist David Blume-permaculture.com. As Barry Commoner said, any system designed badly can have bad results. Never mind the countless studies showing ethanol is energy positive. never mind the many studies showing it can be even more positive with better rotation of crops and variety of crops. One does not rely on a monoculture to manufacture ethanol- beets are especially effective as a crop. certain crops are better equipped to combat soil erosion too. (so before you start saying "WE CAN't GROW SUGAR CANE!" let's take a deep breath and think about all the crops that can be more easily converted to alcohol than corn)

But ultimately where I agree with many anti-ethanol types is on scale. The present agricultural system does not favor efficient, non-polluting use of ethanol. Blume's book will stress do-it-yourself technology and small scale production, integrated with permaculture. BTW, ADM's control of the market shrinks every year as more midwest coops are born. It's a myth to say one corporation's political donations are influencing the subsidy issue. Check out the numbers for yourself.

I also go along with those who fear it will take too long to put this system in place and that allowances haven't been made for this. This applies to all energy systems in general.

BTW, what are the subsidies the oil companies receive? I believe a study has been done showing how much taxpayers pay for a non-efficient, polluting fuel that starts wars. But I digress.

Another website to check is ilsr.org. David Morris has done plenty of work on the subject. Stop spouting off the reports of mainstream media who blithely go off on Pimentel's latest folly and try indepth research on the subject. Ethanol ain't a holy grail but it could prove valuable to peakoilers in small communities in the near future.
 
mlw:  Either you missed it when I calculated the ethanol output from the entire maize crop, or you know of a process which can get a lot more than 2.66 gallons per bushel (plus fermentation byproducts).  If that wasn't an error on your part, how about sharing the info?

Good point about the non-ethanol products ("distillers dried grains", if I am not mistaken) being good for feed for some animals, but cattle aren't one of them; they do best on cellulose, not so well on corn, and the protein-enriched, carb-depleted byproducts would be even worse.  On the other hand, if that spurred a shift of acreage to e.g. switchgrass for fodder it would be a win in all respects.
 
http://www.fightingterror.org/newsroom/050610.cfm

Old or misstated data are sometimes cited for the proposition that huge amounts of land would have to be introduced into cultivation or taken away from food production in order to have such biomass available for cellulosic ethanol production. This is incorrect. The National Commission on Energy Policy reported in December that, if fleet mileage in the U.S. rises to 40 mpg -- somewhat below the current European Union fleet average for new vehicles of 42 mpg and well below the current Japanese average of 47 mpg — then as switchgrass yields improve modestly to around 10 tons/acre it would take only 30 million acres of land to produce sufficient cellulosic ethanol to fuel half the U.S. passenger fleet. (ETES pp. 76-77). By way of calibration, this would essentially eliminate the need for oil imports for passenger vehicle fuel and would require only the amount of land now in the soil bank (the Conservation Reserve Program ("CRP") on which such soil-restoring crops as switchgrass are already being grown.
 
Ethanol actually has come a long way. WHile it is true that the energy balance of corm ethanol is not great, IT IS NOT NEGATIVE. Even counting all trucks, tractors, etc. It is about 80%.

The future is cellulosic ethanol and switch grass. It has better yields per acre than corm and has an energy balance of just 50%. Not too bad considering that normal fossil fuels are at 40% or so by the time it gets into your car.

Ethanol is good for the country, just not Corn Ethanol. So is biodiesel. At $61/barrel Oil, Ethanol is actually at cost parity with gasoline. Both are about $1.40/gallon unsubsidized on the wholesale market.

What we need to do is end farm subsidies and just mandate that all those "extra crops" get converted into Ethanol or some other biofuel.
 
Heiko, didn't you pay attention to the weasel-phrases?  I'll highlight them for you:

"if fleet mileage in the U.S. rises to 40 mpg -- somewhat below the current European Union fleet average for new vehicles of 42 mpg and well below the current Japanese average of 47 mpg — then as switchgrass yields improve modestly to around 10 tons/acre it would take only 30 million acres of land to produce sufficient cellulosic ethanol to fuel half the U.S. passenger fleet."

In other words, replacing most of the US passenger car fleet and building out a huge cellulosic ethanol infrastructure could someday fuel half of the passenger cars.

Nothing for the other half.

Nothing for light trucks, heavy trucks, or other transport.

And once that's done, you've got essentially nothing in reserve if petroleum becomes even more scarce.

My appraisal of this is thinking way too small.  We need to think much bigger.  For instance, GO-HEVs could raise fuel economy to considerably more than 40 MPG and then supply much more than half of the remaining energy demand from electricity; total reduction in petroleum demand could be 80% or roughly the equivalent of one Saudi Arabia.

The zinc energy cycle I propose in Going negative would be able to replace 180% of all surface-transport fuel, not just half of a shrunken demand for passenger-car fuel.  (What do you do with the rest?  It makes electricity, so use it to displace generators fired by natural gas.)

Thinking small is okay for small problems, but not for this one.
 
This argument is pretty much moot.

If the price of gas rises, more affordable alternatives will be developed. If it falls, people will continue to use what is available.

If oil is replaced with say, switchgrass pellets, the demand for oil will go down, and price will drop.

The sensible thing to do is NOT subsidize any technology, including oil, and let the best source win.

JBP
 
The purpose of the subsidy is not to encourage the production of ethanol; The purpose of ethanol is to provide an excuse for the subsidy. By encouraging a supposedly 'environmental' product, the politicians expanded the coalition to a point where it benefited enough people to get legislation passed.

Very well said. I too felt the suspicions of bogus data, such as the 700% yield, as soon as I heard about it. There is no easy solution, in my eyes, but these men would have us think so.

Until we smarten up and rely solely on solar cells or Nuclear Power, we are going to see many crap arguments from these self-serving washington lobbyists.
 
Thanks for getting a great debate started here. I do think you are bit overly negative in your responses (seem more like attacks) to people's posts which may be counterproductive to encouraging debate. That being said, I think there are a couple of points a lot of people are missing:

1) All of the current studies about ethanol/biodeisel refining and their net energy return on investment, as well as your little math about how there isnt enough corn to make replacing petroleum with ethanol/biodiesel feasible, ignore recent developments in biofuels refining methods, specifically a variety of methods that allow refining of biofuels from the cellulose-rich portions of plants. This is not just an small incremental advancement, but a potentially revolutionary one!

These methods, being developed by Iogen (www.iogen.ca/3000.html), BC International Corp (www.bcintlcorp.com), Colusa Biomass Energy (www.colusabiomass.com/default.htm) and others (Novozymes, NREL, Univ of Wisconsin-Madison), all allow utilization of 90+% of the biomass for biofuels, rather than 10-15% contained in the sugary/starchy portions of the plant (also coincidentally the edible parts of the plant like corn kernels). This includes all kinds of agricultural and timber residues such as corn stover, wheat stalks, wood residues and pulping liquor from the timber/paper mill industry etc. It also allow for greater utilization of dedicated perennial crops such as switch grass and other grasses, hemp, and/or trees which are less energy intesive to farm (no need to till, replant etc each year). Perennial crops, as well as the no-till farming practices that would be encouraged by utilizing agricultural residue for biofuels, reduce soil-erosion and increase soil-carbon levels (a good thing). See the "Billion Ton Vision" report form the USDA/USDOE at http://feedstockreview.ornl.gov/pdf/billion_ton_vision.pdf.

In short, this would yield a much larger energy return on investment (Iogen claims a 3:1 return, MUCH better than current standards, see http://sustainabilityzone.com/comments.php?load_this=44), would allow utilization of agricultural and timber wastes - this means you avoid energy costs of growing a dedicated crop; these crops are grown anyway, we are just utilizing the leftovers - as well as less-energy intensive no-till and perennial dedicated crops. All in all, these methods and the available biomass resources (upwards of 1 billion tons and above annually) could allow us to replace 30% or more of our annual petroleum consumption with biofuels! Even taking into account that the 3 to 1 return on investment means you'd need to devote 1/3rd of the produced biofuels to the energy costs of continued production, this would still replace 20% or more of our petroleum use (remember, this assumes using the ethanol to farm more ethanol, rather than diesel/gas, an additional offset of petroleum).

You mentioned not knowing about a refining method refines more ethanol per bushel: well this is it in a BIG way! Not only does it yield more per bushel of already utilized fuel stocks but also opens up a whole slough of other potential fuel sources including agriculture, forestry and urban residue.

Finnaly, GreenFuels (see http://www.greenfuelonline.com/) is commercializing an algae-based biofuels refining system that could be promising as well. It grows algae in tubes that feed on sunlight and the waste heat, carbon dioxide and sulpher of the power plants they are built at. Check it out here: http://www.treehugger.com/files/2005/06/greenfuel_produ.php

2) While I agree with your advocacy for plug-in hybrids of GO-HEVs, I think you are being misled if you think there is only one solution to replacing our petroleum consumption. An amalgam of solutions will likely be necessary and GO-HEVs are not without there problems.

Remember that while GO-HEVs and electric vehicles (EVs) may be a solution to replacing our internal combustion (IC) fleet, we have to keep in mind that any time you send energy into a battery, you lose A LOT of that energy. Most batteries are not very efficient, losing 20-35% of the energy put into them. There are also transmission losses to consider between the wind farm/solar array and your EV which can be considerable as well. Note that this all applies to using the electricity to make hydrogen through electrolysis and power your fuel cell car: fuel cells are only around 40% energy efficient AND you electrolysis is only around 66% efficient meaning you again get BIG losses between the wind farm and your car.

Finally, building enough wind, solar etc to displace our petroleum use (roughly 39% of the US's nearly 98 quadrillion BTUs of energy consumption) ON TOP OF replacing our fossil fuel plants for electrical generation would be an require an ENORMOUS ramp up in alternative energy generation. This may ultimately be what we have to do, but I think it is MUCH more likely and feasible to ALSO utilize a liquid fuel replacement for petroleum - i.e. biofuels produced as described above - hopefully in conjunction with an increase in a mix of plug-in/regular hybrids, EVs and/or Fuel Cell vehicles as well as (why havent we done this already!) higher-fuel efficiency standards coupled with a rapid construction of wind, solar and other alternative energy sources to (initially) replace our fossil fuels burning power plants and (later) to power (H)EVs.

I'd love to see some total lifecycle energy costs, i.e. power from wind farm/solar array etc to miles of driving in your GO-HEV, for your GO-HEV solution taking into account battery efficiencies, transmission losses, engine efficiency etc. and a comparison to biofuels refined using cellulic-refining methods.

Anyway, thats my 2 cents (maybe we should call it 50 cents considering the length of that post). Check out the links and see for your self. Id love to hear your comments too. Cheers...
 
Here's a real two cents, or possibly even as little as two mills. I'm also a big advocate of GOHEVs and believe your analysis and numbers to be fairly thorough. But I also agree with Watthead that you are overlooking some developments in biofuel research.

Additionally, I feel compelled to point out the fact that US petroleum consumption is actually only around 13MM bpd for the transportation sector, and only perhaps 9 million for gasoline. So it would seem you should use one of those figures rather than 20 million and at least revise some of your calculations of the percentage savings upward.

Regardless of those details, however, three cheers for all who are wanting and trying to get "US" off of imported petroleum!
 
WattHead:

I find it very amusing that you parrot my own words back to me about switchgrass and soil erosion (in this thread) and losses from hydrogen.  I get tired of people who don't do their homework.

Regarding the other things:

"1) All of the current studies about ethanol/biodeisel refining and their net energy return on investment, as well as your little math about how there isnt enough corn to make replacing petroleum with ethanol/biodiesel feasible, ignore recent developments in biofuels refining methods, specifically a variety of methods that allow refining of biofuels from the cellulose-rich portions of plants."

What you're talking about is not just fermented grain, but grain, cobs, stalks, leaves, and non-maize biomass processed by a completely different method.  That's changing the definition just a leetle bit, don't you think?

I am concerned about the details of this process.  So far as I know, it has never been used at even pilot scale.  Could there be a showstopper hiding somewhere, like catalyst inactivation or prohibitive expense of sufficiently clean feedstock?  It appears to be a fairly complex scheme, so maybe there's more than one.  The risks appear high compared to the co-production of ethanol and electricity using gasified feedstock and Clostridium cultures (much simpler process, no catalysts, but much lower conversion to ethanol) or the Swiss process for solar-thermal production of metallic zinc (tested successfully at pilot scale).  Production incentives ought to be aimed at schemes which produce, while demonstration money should be aimed at systems ready for demonstration.  The news I've seen about biorefineries puts them at the pre-pilot stage.  FWIW, I'm including research pieces like this in my evaluation.

Then there's the issue of potential.  Biorefineries have much greater per-acre productivity potential than starch fermentation, but the ultimate efficiency of zinc reduction processes (ultimate kWh per acre-year) seems far higher still.  It's unfortunate that I'm stalled on my analytical piece on that very subject or I'd just refer you to it and let you critique it.

"Remember that while GO-HEVs and electric vehicles (EVs) may be a solution to replacing our internal combustion (IC) fleet, we have to keep in mind that any time you send energy into a battery, you lose A LOT of that energy."

Not as much as you think; the efficiency of NiMH and Li-ion batteries appears to be over 90%, as does the small-cycle efficiency of lead-acid.  (The total efficiency of lead-acid falls to about 70% when the overcharging requirements are included, but this is peculiar to lead-acid.)

Zinc-air is a special case.  If the zinc is reduced chemically or thermochemically, there is no electrical throughput to quantify and it has to be compared on the basis of inputs.

"Finally, building enough wind, solar etc to displace our petroleum use (roughly 39% of the US's nearly 98 quadrillion BTUs of energy consumption) ON TOP OF replacing our fossil fuel plants for electrical generation would be an require an ENORMOUS ramp up in alternative energy generation."

Yes, it would.  But I'm finding tantalizing hints that it is not only possible, but a lot easier than it looks.  There are a few points of leverage which could yield a great deal more ultimate product (power at the point of use) for the same input than we are getting now, and the consequences could be enormous.

I invite you to post another 50¢ or even $5 worth, but of analysis and cites.  If you want to have a dialogue between two blogs, go for it.  I'm all for sorting out the errors and omissions, but this takes solid facts and critical thinking; people who haven't done their homework can contribute nothing but useless noise.
 
Iogen has a 260,000 gallons per year cellulosic ethanol pilot plant. The G8 leaders used that fuel in their cars at their latest summit giving it a bit of publicity.
 
What about svo and rvo (used veggie oil) that has been "processed" (glyserine taken out) as an adjunct to diesel trucks and cars?

It would not solve the problem of middleeastern oil, could it not provide some relief?
 
If I recall correctly, cooking grease use in the USA amounts to roughly a billion gallons per year.  (Correct me if I'm wrong.)

Contrast this to 64 billion gallons/year of distillate fuel consumption, and 8.94 million bbl/day (137 billion gallons/year) of gasoline.

Each billion gallons of waste grease, converted to biodiesel, would offset about 0.5% of the combined gasoline and distillate fuel used in the US.  Whatever relief this could provide, it would be very small.
 
Well, Enginseer. It seems that you have confirmed my initial comment about how negative your responses can often be. Forgive me for turning a bit negative myself in this comment as this is the inevitable result of the tone you seem to take with your readers. I am simply trying to offer another perspective on your post and offer some additional considerations that seemed to be absent from the debate and you respond with:

"I find it very amusing that you parrot my own words back to me about switchgrass and soil erosion (in this thread) and losses from hydrogen. I get tired of people who don't do their homework."

Well, forgive me for not reading your ENTIRE site before posting a single comment. But rest assured, your's is not the only source of energy news out there and you might be able to tell from the number of links in my previous comment that I HAVE done my homework on cellulosic-biorefining processes.

You write, "What you're talking about is not just fermented grain, but grain, cobs, stalks, leaves, and non-maize biomass processed by a completely different method. That's changing the definition just a leetle bit, don't you think?"

Yes, it IS changin the definition a "leetle bit." That was the whole point! As I wrote before "This is not just an small incremental advancement, but a potentially revolutionary one!" This is a whole different refining process and it HAS been implemented on a pilot level by Iogen as Heiko kindly pointed out. Its being further developed by a NUMBER of companies (see the links in my previous comment and do your homework).

All I wanted to add was that you were giving the potential of biofuels an unfair reading by simply not considering new cellulosic-refining methods. As I also said before, I AGREE with you on your advocacy for GO-HEVs and for the generally ignored potential of Zinc-air batteries. I dont meant to offer biofuels as an either/or counter to Zinc-air and/or GO-HEVs. My aim was to point out that biofuels have more potential than you have given them credit for and several distinct advantages (most notably little/no change required in the engines of cars and the distribution method: biofuels are a liquid fuel and can run in existing engines) In accordance with my fervent opinion that a using a number of promising fuel sources to kick our petroleum habit is the most realistic scenario, I wanted to offer biofuels up as another option, IN ADDITION to GO-HEVs.

As for your Zinc-air solution, I am very intriuged and will read more. Can you provide links to where you got the battery efficiencies for li-on and NMH you cited? Also can you expand on your comment that "There are a few points of leverage which could yield a great deal more ultimate product (power at the point of use) for the same input than we are getting now, and the consequences could be enormous."

Perhaps I will continue this thread by making a post on this topic on my blog in the near future (I have a number of other topics that may take precedent). Feel free to comment then and continue this discussion.

If you really think that my comments lack "solid facts and critical thinking" and contributed only "useless noise," then I thank you for insulting my intelligence and will kindly stop posting on your blog. However, I would then question your ability to sustain a vibrant discussion and would again caution you that taking such a negative tone immediately prompts your readers to go on the defensive and that accomplishes little.

I apoligize for my tone in this post and will try to return to my usual civil attitude in the future. I hope you can do the same. Cheers...
 
http://www.eesi.org/publications/Newsletters/ECO/bco%2024.Biodiesel%20for%20DOTs.pdf#search='cooking%20grease%20usa%20consumption'

interesting article about bio-diesel being used by state's dot

assuming 1 billion gallons of svo could be sold this is 3 billion dollars that would not go into opec's pocket
 
Watthead, is it too much to expect someone to have read the current thread before lecturing a poster on their position?  Your indignant response amounts to "how DARE you prove that I was wrong about your position, which you posted above!"  If you wanted to know if I'd posted about anything else, Google would do (I won't demand this of anyone because I seldom do it myself, but if someone claims I mean the exact opposite of what I've already stated in the thread I have no compunctions about using more than one cite to take the wind out of their sails).

On to biofuels.  If you look at this thread you'll see exactly why I'm hostile:  I see the advocates as mendacious and self-serving, more interested in making money off the problem than solving it.  Misdirection is required for this to continue.

Heiko's conduct is, unfortunately, typical.  Look at these exchanges (Heiko in italics, mine in bold, explanation in (parentheses), all quotes hotlinked):

2. It doesn't have to be fossil fuels, it could all come from renewables in principle. (In principle, biofuels can be more than a method of "laundering", and collecting subsidies on, what amounts to 60% or more fossil energy.  But they aren't now.)

At the 1.67 EROEI which is the best cited for ethanol, it would take 2.5 gallons-equivalent of gross production to produce 1 gallon net. This is not a system which can run itself. (If you stopped the fossil pass-through the economics of today's so-called "biofuels" would fall apart.)

Ethanol doesn't get used to provide any of the inputs. (My complaint is re-iterated.  As an excuse?  Hard to tell.)

That particular discussion goes around in circles with Heiko refusing to admit that ethanol as currently produced is not remotely renewable, not a replacement for fossil fuels, and collects large subsidies for the 60-75% of its gross energy output which is passed through from those fossil sources even though his own claims lead directly to those conclusions.  I do not use the term "mendacity" lightly.

Last:

if fleet mileage in the U.S. rises to 40 mpg -- somewhat below the current European Union fleet average for new vehicles of 42 mpg and well below the current Japanese average of 47 mpg — then as switchgrass yields improve modestly to around 10 tons/acre it would take only 30 million acres of land to produce sufficient cellulosic ethanol to fuel half the U.S. passenger fleet. (quoting a bunch of weasel phrases.)

The above weasel-stuff is all but certainly factually inaccurate as well; 300 million short tons of bone-dry carbohydrate converted to ethanol assuming no byproducts other than CO2, e.g. 3 CH2O -> C2H5OH + CO2, would yield only 153 million tons of product with energy equal to just 96 million tons of gasoline.  96 million tons of gasoline at a bulk density of 6.167 lbm/gal is 31 billion gallons, or a mere 23% of current US gasoline consumption with nothing for diesel.  All those ifs add up to a whopping misdirection.  This is probably Iogen's propaganda rather than Heiko's, but his credulous repetition of the deception does nothing to raise the level of discussion or lead to an actual solution of the problem.  Instead it promotes a waste of effort on avenues which profit farmers, distillers and "biorefiners" at the taxpayer's expense, and promises to keep the gravy train rolling by never actually replacing petroleum.

Enough of why I think most ethanol advocacy is grossly dishonest; suffice it to say that I find such misrepresentation both offensive and destructive (for reasons why, read "On Bullshit"), and I challenge it accordingly.

"why does using GO-HEVs in any way preclude using biofuels as well?"

You can see from the above that the biofuels are largely (at least 60% and as much as 75%) a subsidy-financed laundry for fossil fuels.  I suspect that the same amount of money spent on other efforts would yield a much larger payoff; I'm 100% certain that the same amount of land devoted to energy production via wind and thermochemical zinc reduction could produce many times the yield, including a complete replacement of all petroleum used for ground transport.

The problem is that the "biofuel" lobbies have almost completely captured the incentive structure, while eliminating promotions for measures which would work more effectively than theirs.  In other words, biofuels are trying to preclude GO-HEVs.  This has to be fought, and the only available tool is public disgust with the misuse of their money.
 
As Watthead says, your tone is not conducive to civil discussion, and, in fact, you do take the term "mendacious" rather lightly.

Look, present day ethanol production is not just about energy production, but also about converting lower grade energy sources into a higher grade output. If we could take 1 kWh of coal and turn it into 1 kWh of liquid transport fuel that would be brilliant, even though no fossil fuel has been displaced.
That point just seems to go over your head.

We can't put wood, which has a net energy of 40:1 or so, into a petrol tank.

We can use it to provide process heat for distilling ethanol, and we'd jolly well do that rather than use the ethanol itself, which can go into a petrol tank.

When I make that point, you claim I am "reiterating your complaint"???

Ethanol as currently produced in the US has a fossil fuel content, about half that of gasoline (1.23 kWh of fossil fuel are required to produce 1 kWh of gasoline at the pump, only 0.6 kWh of fossil fuel are required to provide 1 kWh of ethanol at the pump).

When I talk about further improvements, you brush it aside. What on Earth is so wrong with supporting a technology partly for its future potential? And to get it to advance?

Ethanol doesn't get large subsidies, it does, as currently produced, yield only a modest reduction in GHG emissions, and whatever subsidies it does get, will appear larger when compared with the GHG reduction, rather than with the liquid fuel displacement.

And you don't read my posts terribly carefully either. The section you try to critique doesn't come from the Iogen site. To work out where it does come from requires merely following the link I originally gave.

Biofuels in no way preclude plug-in hybrids. I find it dishonest of you to claim so, or to claim that ethanol gets more support than plug-in hybrids, knowing full well what gasoline prices are in Europe and Japan, and what that means in effective support.
 
"We can't put wood, which has a net energy of 40:1 or so, into a petrol tank."

We can't?  Looks to me like it's been done.  The other fuels used for distillation (LPG, natural gas) don't even require processing, just a modified fuel system.

The one point you have is coal.  However, coal appears to be used for a very small amount of the distillation heat for ethanol, and subsidies are not restricted to ethanol distilled without petroleum or natural gas.  This puts ethanol production in direct competition for fuels used for e.g. home heating, and receiving an unfair subsidy to boot.

This reminds me of the situation in the former Soviet Union.  Bread was subsidized to compensate for low wages, so pig farmers found it cheaper to feed their swine with bread than maize.

"When I make that point, you claim I am "reiterating your complaint"???"

Well, let's see.  You won't acknowledge the subsidy situation regarding increasingly scarce and expensive fuels required for home heating except with "Ethanol doesn't get used to provide any of the inputs", which is sort of an acknowledgement and sort of an evasion.

If the typical ethanol distillery was fired by corn stover or heated by exhaust steam from an electric powerplant (esp. coal-fired), I would be much more favorably inclined towards it.  Rather, I'd be more in favor of it if no subsidy money went to ethanol distilled with natural gas, LPG or (heaven forbid) fuel oil.  Unfortunately, the subsidy scheme was poorly crafted from the beginning and this appears to be the exceptional case.

"Ethanol as currently produced in the US has a fossil fuel content, about half that of gasoline (1.23 kWh of fossil fuel are required to produce 1 kWh of gasoline at the pump, only 0.6 kWh of fossil fuel are required to provide 1 kWh of ethanol at the pump)."

The accounting for those numbers is ofen careless.  What's the source for that one?  Make sure that that 0.6 kWh is measured at the well-head rather than at the pump (compare apples to apples).

"When I talk about further improvements, you brush it aside. What on Earth is so wrong with supporting a technology partly for its future potential?"

What on earth is right about supporting widespread production of a fuel which is nearly as wasteful as feeding bread to pigs?  If you need molecular sieves, you shouldn't subsidize distillation.

"Ethanol doesn't get large subsidies"

The energy created by the process (vs. passed through from fossil sources) gets a very large subsidy.  I call $1.27 (1.67:1 EROEI) to $2.01 (1.34:1 EROEI) in federal subsidies per gallon-equivalent very large; even the lower value is about half the pump price.

"Biofuels in no way preclude plug-in hybrids."

The ethanol lobby has been receiving subsidies for years, amounting to tens of billions of dollars; they got this for what they claimed was promoting energy independence (when the EROEI may have been less than 1) and pollution abatement (when their product appears to have increased evaporative emissions).  Plug-in hybrids are finally getting a few tens of millions in the energy bill just passed, despite superiority in both departments.

"The section you try to critique doesn't come from the Iogen site."

I critiqued the substance (and your credulousness in quoting it without analysis), not the source.

"I find it dishonest of you ... to claim that ethanol gets more support than plug-in hybrids"

Ethanol subsidies:  51¢/gallon times ~4 billion gallons/year = ~$2 billion/year, going to be ~$2.5 billion soon.  Ethanol has been subsidized for ~20 years now.
PIH subsidies:  $40 million over 5 years, or $8 million/year.  There was no effort to promote PIH's until this bill.

Pot, porcelain, black.
 
E-P: Once again I think you are missing the point I was trying to raise. First, I am NOT advocating the existing ethanol refining processes and the subsidies they recieve. Seperate my arguments from Heiko's and you'll see this. I dont object to your description of existing subsidies as large, I accept the figures for the low EROI of conventional ethanol processes AND I think the solar-zinc process you describe has a lot of potential, as do GO-HEVs. We agree here on just about every point.

Where we seem to be continually missing each other is on the fact that I want you to consider cellulosic-biorefining processes, NOT the status-quo process. Lets not talk about policy. I dont want to talk about subsidies, just the potential of this new process to provide a petroleum fuel replacement.

As you say, If the typical ethanol distillery was fired by corn stover or heated by exhaust steam from an electric powerplant (esp. coal-fired), I would be much more favorably inclined towards it."

Well this is exactly the kind of change in refining methods I'm talking about. You seem like a smart guy with a good grasp the energy industry and the ability to do in depth research. So lets put your skills to use and lets see an examination of the potential of cellulosic biofuels from you. I'm tired of arguing apples and oranges with you. Your arguments against ethanol as the industry stands now are largely valid. Lets talk about what could be and not what is now. And please, lets keep our minds open to new options. One quick fix isnt likely to solve all our energy problems, however promising it (it being zinc-air for you it seems) is. Give cellulosic-biofuels a fair hearing and we'll compare it to zinc-air, GO-HEVs and combinations thereof.

Cheers...
 
Give it a fair hearing?  I thought I did:  300 million tons of biomass converted to ethanol could produce (at most) the equivalent of 96 million tons of gasoline, or 23% of US gasoline consumption (perhaps 14% of total motor fuel consumption).  Even a billion tons a year would not replace gasoline.

Biofuels are worthy subjects of research as means of turning agricultural and forestry waste into useful products.  So's trash to energy, turkey guts and grease-trap waste to oil, etc.  But none of these should be touted or subsidized for the purpose of replacing petroleum, because they can't come close even in principle.

This probably doesn't surprise you, but government in general (both US and foreign) is largely a creature of special-interests and rent-seekers.  Ethanol and biodiesel are the pet projects of the ag lobby, grants for hydrogen finance a bunch of research labs and arms of auto companies, etc.  All of these have well-financed publicity efforts, and none of them will solve the nation's energy issues in the next 2 decades.

Countering such well-oiled PR machines takes facts and the will to use them.  I'm not about to pull any punches; all the rent-seekers are the enemies of solutions, and thus mine.
 
Another ethanol-specific subsidy I forgot to list above, this one indirect:  Auto manufacturers are required to build their vehicles to accomodate alcohol fuels (up to E-85 for many models).  There is no corresponding mandate for electricity.
 
Fast pyrolysis is my area of research, so I am all too aware of the fact that pyrolysis oil has a lot of potential, but cannot be put into a petrol tank without upgrading.

You don't really answer Watthead's point. If ethanol replaces 20%, and efficiency/electricity replace 80%, what's the problem with that?

I don't really want to talk "potentials". As I said in a previous post, much better batteries => liquid fuels might be outlawed, much better yields though genetic improvements => cheap biofuels easily displace petroleum.

But, the US has:
http://www.hpva.org/forest%20facts.htm
2.263 billion acres

30 million acres is 1.3% of that total.

Nonetheless, I figure that with present technology petroleum will continue to provide the bulk of transportation demand for a fair while, even on conservative assumptions about depletion:
http://www.geocities.com/hgerhauser/Depletion1.xls

What I do want to expand on is the topic of subsidies and costs.

No alternative fuel gets large subsidies in the US. Nat gas, LPG, electricity all get support, not too dissimilar from ethanol, but not enough for them to be viable beyond a tiny niche.

The only government measure with a big impact on gasoline demand is CAFE. Mileage has gone up from 13 miles per gallon or so to 21 miles per gallon or so, that represents a lot of gasoline, around 80 billion gallons, a lot of this arguably due to CAFE.

Putting a cost to this is quite hard, as there are two ways of meeting the mandate, conservation (smmaller cars) and efficiency (same utility car sipping less fuel).

In so far as the mandate forces people into smaller cars, there is no monetary cost. The smaller cars are both cheaper and more fuel efficient, so the mandate saves the owner money (outlawing cars outright would save people even more money, though).

In so far as the mandate favours efficiency, however, the cost per gallon saved can be quite high. The big car manufacturers are more than happy to produce E85 capable cars (which are about $150 per car more expensive than standard cars) in exchange for a little relaxing of CAFE. But I think, clearly consumers are willing to pay a lot more than $150 to get high performance vehicles that still meet the CAFE standards.

Which gets me onto Europe, where there are large "subsidies" available for efficiency, hybrids, LPG, diesel, nat gas, electricity and biofuels (with great differences between countries, until recently for example ethanol got slammed with the same tax per litre as petrol in the UK, even though that amounts to taxing ethanol 30% higher than petrol on an energy basis).

In Germany, nat gas for example gets around $2.50-$3 per gallon gasoline equivalent, and even with that large a subsidy take-up is still fairly limited. The main reasons are firstly nat gas cannot be put into a petrol tank, major changes to the car are required, which currently come to about $3000 in extra cost. The cars sold tend to be bi-fuel, as the range on nat gas alone for eg a Berlingo is only about 120 miles, compared to over 600 on gasoline. And extra room gets taken up by the nat gas storage, reducing the effective utility of the vehicle.

Let's compare that subsidy with the ethanol subsidy in the US. There is no fossil fuel saving. In fact, slightly more fossil fuel is required, so on a fossil fuel saved basis, the subsidy is infinite per barrel of gasoline equivalent. Ethanol in the US, on the other hand, comes with about a 50% saving compared to gasoline.

Let's look at hybrids instead. In the US, they get two principal subsidies. No tax is due on the gasoline saved, which amounts to an average of 42 cents per gallon and about 50 cents per gallon in California, and there is a direct subsidy when purchasing a hybrid (there's also a few other perks such as HOV lane use). But in Europe, gasoline is taxed at around $4.50 per gallon. Gasoline displaced via (plug-in) hybrids is not taxed, which makes for an effective subsidy of $4.50 per gallon. Yet, not a single plug-in hybrid has been sold in Europe and sales of hybrids are a fraction of what they are in the US.

And the $4.50 isn't the end of it, there are plenty more tax breaks. In London, you'd get exemption from the congestion charge (£8 or about $15 per day, make that $3000 per year for people needing to drive into central London on 200 days per year), reduced vehicle taxes and a grant from the government.

The g-whiz, an all electric car, also gets free parking, reduced rates on insurance, reduced vehicle taxes.

All in all I figure that even at $10 per gallon subsidy levels, plug-in hybrids and all electric cars are struggling mightily.

And all this subsidy activity applies to electric or plug-in cars no matter what the source of the electricity, you could argue that part of this is just a pass-through to fossil fuels.

This is easily remedied, as the bulk of the subsidy requirement to make people buy EV's or plug-in hybrids can be found in the drawbacks of today's battery technology.

Which nicely leads on to zinc.

The zinc air battery system requires exchanging of the battery at the filling station, and energy density is not all that different from standard batteries, where there is at least the option of charging overnight rather than outright battery removal.

Looking at the data:
http://www.electric-fuel.com/evtech/index.shtml

Notice the energy density. 200 Wh/kg, or 0.2 kWh per kg. Petrol is over 10 kWh per kg, ie more than 50 times better.

Engineer poet was mighty impressed with the claimed efficiency of converting 1200 degree solar heat into a fuel. I wasn't. With a lower temperature thermochemically splitting water also yields about 50% efficiency, and with the postulated carbon input, we can turn that into a liquid fuel via liquefaction.

It's nothing new or exciting as far as I am concerned and the main, but far from only, difficulty is getting renewable heat at that temperature, which is what at present would yield astronomical costs for this process.

To sum up, you are dreaming, if you think the lack of success for zinc, EV's and plug-in hybrids so far is due to ethanol hugging all the subsidies.

Sure, support for farmers is an element, but the main reason corn ethanol is doing so well is that it is the lowest cost fuel available at present as an alternative to petroleum derived fuels in the road transportation sector in the United States. Using nat gas or, much more so, electricity either requires large upfront costs to come up with synthetic gasoline, or large costs to obtain a car that can take the fuel and provide the same performance as on gasoline.
 
This comment has been removed by a blog administrator.
 
"But, the US has... 2.263 billion acres.... 30 million acres is 1.3% of that total."

It's a much larger fraction of the arable land.  Alaska has 420 million acres compared to ~80 million planted to corn, but that doesn't mean we could quintuple maize production by plowing from Anchorage to Prudhoe Bay.

"If ethanol replaces 20%, and efficiency/electricity replace 80%, what's the problem with that?"

The problem is that the USA has spent a thousand times as much money on the 20% than on the 80%, because the people who'd supply the 20% have good political connections.  Thirty billion dollars in subsidies so far and they're up to what, 5%?  The same spent on wind, solar and batteries would have yielded far more than that.

"The only government measure with a big impact on gasoline demand is CAFE."

All CAFE has done is promote the explosion in miles driven.  It has done next to nothing to decrease gasoline demand.  Gasoline consumption decreased from 1977 to 1982, but has been on a steady upward trend since then.

The only thing that actually restrains demand is high prices.  The US is unwilling to restrain demand with taxes, so it appears that we have to wait for depletion to do it for us.

"(outlawing cars outright would save people even more money, though)"

Two words:  opportunity cost.

"Which gets me onto Europe, where there are large "subsidies" available for efficiency, hybrids, LPG, diesel, nat gas, electricity and biofuels"

There's one issue there, and that's electricity.  Despite the cost advantage, there are no plug-in hybrids being sold by major manufacturers.  Why?  I suspect that government regulatory barriers are a large factor.  A high-taxing government would have every (perverse) incentive to prevent adoption of electric propulsion in order to protect its revenue.  This is part of the normal logic of government (the treasury department and environment department don't necessarily talk to the energy department) and requires political attention to override.

"Yet, not a single plug-in hybrid has been sold in Europe and sales of hybrids are a fraction of what they are in the US."

So far as I know, not a single plug-in hybrid has been sold anywhere, because not one has been brought to market.  This is because manufacturers are either stuck in a rut (which they are), are afraid they couldn't sell a vehicle with "plug stigma" (Toyota's people definitely show this tendency), or fear being tied up in regulatory hell by governments afraid of losing petroleum tax revenue (or regulators trying to protect their turf; zero emissions means no jobs for the people in charge of emissions compliance).

The plug-in hybrid could have been part of California's air-quality strategy starting in 1990, or even Carter-era energy initiatives in the late 70's.  Instead, it took the introduction of the Prius (the first mass-market hybrid that can run entirely on electricity, even if only at low speed) to provide the baseline for individual hackers to start making them.  That took until what, 2003?  That's 13 years of delay, and this time the push is coming not from industry, not from government, not from special interests, but from the grass-roots.

You really do have to ask "cui bono?"  Only the public would have benefitted, and the public is too diffuse an interest to achieve traction in the process.  The agriculture, petroleum and natural gas lobbies (LPG is produced by the latter two) did very well.

"In London, you'd get exemption from the congestion charge (£8 or about $15 per day, make that $3000 per year for people needing to drive into central London on 200 days per year), reduced vehicle taxes and a grant from the government."

Have you looked at the requirements to qualify for the exemption?  I quote:

"To qualify for the alternative fuel vehicle discount from Congestion Charging, your vehicle must be powered by an alternative fuel and not solely by petrol or diesel....  To be eligible, a vehicle may either have been manufactured to run on an alternative fuel, or it may have been converted to run on an alternative fuel, but the vehicle type and the conversion supplier must be listed in the appropriate band on the TransportEnergy PowerShift Register, or listed as meeting an equivalent standard on the TransportEnergy PowerShift Register."

In short, a Prius does not qualify and someone would have to go through the bureaucratic procedure to get their particular Prius+ conversion listed before it would qualify.  This is a system which favors the big and well-connected.

The electrics being sold in Britain all appear to be low-speed, short-range vehicles.  To be able to use one, the owner would have to live either inside or within a relatively short distance of London and be able to use roads with low speed limits to get there.  With all the restrictions, the number of people who can actually use electrics is small, and until a conversion is qualified for the Prius or another hybrid the number of plug-in hybrids which qualify is ZERO.

"Notice the energy density. 200 Wh/kg, or 0.2 kWh per kg. Petrol is over 10 kWh per kg, ie more than 50 times better."

Notice three more things:
* The Electric Fuel unit is a prototype, designed for a bus, and is perhaps 1/7 zinc by weight.  Building a unit which is 1/3 zinc by weight would achieve 470 Wh/kg.
* In-use refuelling of a zinc-air fuel cell has already been demonstrated, IIRC.
* The zinc-air battery also performs the conversion of chemical energy to work; it's not just replacing the fuel tank, but the engine too.

If energy/mass was crucial for vehicular applications, something as poor as 200 Wh/kg would never have been able to run a bus for a day.  That's obviously not true; 200 Wh/kg is good enough for a bus.  Heck, it's more than good enough for the lithium-ion tzero (a 18650 cell at 43 grams and 7.2 Wh is only 167 Wh/kg), and that's a rocket car by anyone's standards.

None of your objections hold water; there are too many existence proofs to the contrary.

"Engineer poet was mighty impressed with the claimed efficiency of converting 1200 degree solar heat into a fuel. I wasn't. With a lower temperature thermochemically splitting water also yields about 50% efficiency, and with the postulated carbon input, we can turn that into a liquid fuel via liquefaction."

I'll let you work out the end-use efficiency of this scheme and tell me how much you could accomplish with e.g. a ton of biomass.  But there's one thing you'll never be able to do with it no matter what, and that's make it carbon-negative.
 
Oops, looks like I gave ethanol way too much credit; it looks like it makes up maybe 1.5% of total gasoline consumption (and nothing for diesel, jet fuel, heating oil...)
 
Hmmm, that was supposed to be a link to http://www.eia.doe.gov/cneaf/alternate/page/datatables/afvtable10_03.xls. Is Blogger censoring me?  Let's try this again:

Linky.
 
Funny how I looked up the same table earlier today, the 2004 projection turned out to be a bit too low, it was actually over 3 billion. This year it should be around 4, still that's a bit less than 3% or thereabouts, not 5.

http://www.carpages.co.uk/toyota/toyota-prius-07-04-05.asp?switched=on&echo=435477191

At least in this link, which I quoted earlier, it is claimed that the Prius is exempt from the congestion charge.
 
carpages refuses to let me read their site without enabling their cookies.  No Google cache either.  Screw 'em.

The cclondon.com site has zero Google hits for "Prius".
 
E-P, you write: "Give it a fair hearing? I thought I did: 300 million tons of biomass converted to ethanol could produce (at most) the equivalent of 96 million tons of gasoline, or 23% of US gasoline consumption (perhaps 14% of total motor fuel consumption). Even a billion tons a year would not replace gasoline."

First of all, is 300 million tons of biomass to ethanol equals 96 mil. gal with existing or cellulosic refining? Either way, if 300 million tons = 23% of US gas consumption, than 1 billion tons = 76.6% of US gas consumption by my simple math. Couple that with an increase in fuel efficiency, say to an average of 30-40 mpg and you can replace the entirety of US gas demand. Use GO-HEVs to get up to 70+ mpg and we have an excess of supply.

These numbers are rough of course but the point is that the potential for biofuels is not as shabby and inconsequential as you imply. Can it get us carbon neutral? No. Should it be subsidized? Maybe not. Does it require different refining methods? Yes. Does it have a lot of potential? Yes. That's all Im sayin'.

Cheers...
 
"First of all, is 300 million tons of biomass to ethanol equals 96 mil. gal with existing or cellulosic refining?"

That's assuming stoichiometry and no products other than ethanol and CO2; I laid it out in this comment.

In other words, you can't do any better without transmuting something.

For the energy figures, I took numbers out of the Rubber Bible:  12780 BTU/lbm for ethanol, 20460 BTU/lbm for gasoline.
 
"I laid it out in this comment."

Right. So what's a more realistic conversion number for 1 billion dry tons of biomass into biofuels with cellulosic-refining?

My point above still stands, even if we have to reduce the conversion ratio below the ideal 300 million dry tons = 96 mil gallons by some percentage to account for other byproducts etc. Even if 300 million tons only accounts for 15% instead of 23% of gasoline consumption for example, 1 billion dry tons still could displace a sizable amount of our current petroleum demand (i.e. 50% in this example).

Im still just pulling numbers out of the air because I havent seen anything more concrete but the point is that you can't so quickly dismiss the potential of biomass (just in terms of being able to supply enough fuel, not considering other concerns like costs, subsidies or the logistics of ramping up to this level of supply... Im just talking sheer potential).
 
While it would be interesting to know exactly how efficient cellulosic processing is (including the energy cost of hydrolyzation), I went with the stoichiometry because I wanted to know exactly what was theoretically possible at the limit.  You can't do any better than that, so it cuts off pointless argument.  Or so I thought. ;-)

At this point I'm more interested in the possibility of producing char from biomass (feedstock for zinc reduction).  Unfortunately, I've had as little success turning up data on that as it appears you have regarding fermentation efficiency.

There's a policy issue here because both cellulosic ethanol and a biomass-driven zinc reduction process compete for the same feedstocks.  Suppose you are correct, that we could use ethanol to replace half of motor gasoline; what's the opportunity cost?  If we could use that same biomass to capture, store and deliver enough energy to replace all motor fuel (not just half the gasoline, but all of it and the diesel too) we would be fools to promote its use for ethanol; that would be wasting perhaps 3/4 of its potential.  Yet that is exactly where our public policy is headed.
 
Now we are getting somewhere E-P. You write, "There's a policy issue here because both cellulosic ethanol and a biomass-driven zinc reduction process compete for the same feedstocks. Suppose you are correct, that we could use ethanol to replace half of motor gasoline; what's the opportunity cost? If we could use that same biomass to capture, store and deliver enough energy to replace all motor fuel (not just half the gasoline, but all of it and the diesel too) we would be fools to promote its use for ethanol; that would be wasting perhaps 3/4 of its potential. Yet that is exactly where our public policy is headed."

Yes, there are a lot of issues here, comparing and contrasting the potential of various options for replacing petroleum. I think zinc-air is very promising as well. My point this whole time has simply been that biofuels ARE one of those options that should be considered. I'm planning on working on this very subject throughout the next year and would like to find those fermentation efficiency numbers (if you find them, post them and let me know). We should do exactly what you mention: compare the opportunity costs, comparitive efficiency and potentials of various options (biofuels, GO-HEVs, hydrogen fuel cells, and zinc-air) and see what our best option is.

We CAN kick our petroleum addiction. We have multiple options. Its time to decide which one is best and get crackin'. As you wrote elsewhere, " If we want to, we can do it."
 
Watthead,

The potential depends very much on yields (10 tonnes per acre is high I should add and assumes some improvement from where we are now), how much land we are willing to devote to biomass, and on cost.

The 30 million acres are 1.3% of US land. They are used in the example as that many acres are in the soil bank (the Conservation Reserve Program ("CRP") on which such soil-restoring crops as switchgrass are already being grown.

Devoting 300 million acres to switchgrass production would take 13% of US land, yielding enough biomass to replace all petroleum and have some to spare.
 
E-P,

as my area of research is pyrolysis, I could provide plenty of information on the production of char.

Biomass consists of ash, lignin, cellulose, hemicellulose and extractives.

When pyrolysing biomass, CO, CO2, H2, H2O and CH4 will be formed and virtually all of the ash will stay in the char.

However, pyrolysis does not transform CH2O (ie biomass) nicely into C plus H20. The higher the pyrolysis temperature, the higher the C content of the char for a given residence time (on an ash free dry basis), but also the lower the yield.

So, you may get a say 40% yield of a char that's 70% C, and if from grasses, contains something like 10% ash.

That char may not be what you'd want for say reducing zinc. In particular,
ash components like potassium may contaminate the zinc, which might cause problems.
 
If the process could reduce potassium to metal, it might be far more profitable than if it could only reduce zinc.

The thing I'd be concerned about with the biomass process isn't potash or soda but silicates.  Zinc forms several silicates, and if they are sufficiently stable they would be a route for zinc loss from the process.  (My data don't include heats of formation; OTOH calamine is listed as a zinc ore so it would appear that zinc loss via that route could be made up by adding a bit more calamine.)

I'm aware that biomass can't be decomposed to carbon and water; on the other hand, nobody appears to be working on maximum carbon yield from a pyrolysis process so that information is hard to come by on the web. ;-)  Slow pyrolysis would appear to be optimal for that, with volatiles driven off as small molecules.

Slow pyrolysis seems to be disfavored because it produces tars, which are difficult to process.  On the other hand, tars can be pyrolized in turn or might be a feedstock in their own right.  I could see a biomass process which takes dry matter and produces 3 product streams:

1.  Stable char, for use as a reducing agent either immediately or later.
2.  Tars and liquids, for fuel or chemical synthesis.
3.  Gases, which either go for fuel or are fed to something like Clostridium synthesis for production of ethanol or other liquids.

Ethanol is a worthwhile product, but I have a problem with it being set as the goal to the exclusion of all else.  If we have pyrolysis gas beyond immediate needs and no means of storing it, converting it to ethanol is better than wasting it.
 
All right, our group works on fast pyrolysis, and the key benefit of fast pyrolysis is that it maximises liquid yields, so we are only interested in the char as a by-product.

The reason there is less research on processes maximising charcoal production is that it is perceived to be a low tech niche application: charcoal for barbecues, reduction of iron ore in a few developing countries, activated charcoal and production of silicon to name a few key areas.

But as I work in the field I do stumble across people who do research specifically on charcoal production for its own sake.

Michael Antal's particularly active there:
http://www.hnei.hawaii.edu/bio.r3.asp#flashcarb

Mike Connor's a nice fellow who's also done some work, but the key article I remembered is in conference proceedings (of a conference I attended and where I met him).

Gabor Varhegyi and Morten Gronli have done a lot of fundamental work, mostly TGA.

Anyways, you'll probably find the link to Michael Antal's group most helpful.

Maybe you could expand a bit on potential "show stoppers" for zinc, and also on how does it differ from batteries (in terms of drawbacks and advantages)?

Why would it be better than thermochemical splitting of water followed by hydrogenation of biomass?
 
A few quick comments on ethanol:

There's a pretty pure CO2 side stream, so ethanol production can be made net carbon negative. There's a DOE project to use carbon dioxide from an ethanol plant for enhanced oil recovery.

Alternatively, if an external energy source is used (hydrogen from wind, or thermochemical water splitting), there's nothing impossible about the theoretical limit you list, pretty much all the C in the biomass could be used for producing a liquid transportation fuel (CH2)n.
 
My main concern with zinc is that it appears worse than simply sticking to ordinary batteries:

With heat at 1200 degrees C, we should be able to generate electricity at the same efficiency as modern combined cycle natural gas fired power plants, make that 60%.

So why go via zinc? This merely seems to be about storage and transmission. But car batteries could provide the same kind of storage capacity, and transmission losses via HVDC are quite modest.

To generate hydrogen, there are other thermochemical cycles that can do greater than 50% efficiency, which would be hard to reach with zinc as an intermediate step.

200 Wh per kg, and 90 W per kg are terrible numbers. 90 W per kg means 1000 kg to get 90 kW.

So:

1. Zinc air fuel cells need considerable work for this to be viable commercially (or at least more viable than ordinary batteries).

2. The costs for generating solar heat at 1200 degrees C are somewhat uncertain and definitely not low.

Let me compare zinc and ethanol:

Ethanol is easy to distribute, it just gets mixed in with ordinary petrol. No investment in cars is required up to 10% and the investment for going to E85 is minuscule ($150 per car). The feedstock for ethanol plants is readily available in commercial quantities and well defined and most of the cost of the finished ethanol is in the corn feedstock. The only investment required is in ethanol plants, and that runs to about $1.50 per gallon with very short lead times.

Solar zinc would require massive investment in solar thermal plants and into new cars, the refuelling infrastructure would be by comparison a minor afterthought.

So it's not a near term alternative to ethanol for powering transportation. It's a dream for the future that'll require technological advances to compete, or very high energy prices.

Now zinc air fuel cells can be used in the near term, with enough subsidies forthcoming for the cars. The zinc though would initially be produced from fossil fuels in all likelihood, if it is to be used in significant amounts (otherwise even higher subsidies would be required).

In which case you could moan that zinc is all about subsidising fossil fuels and how mendacious the zinc lobby is in promoting their fuel to garner subsidies.

Funnily enough, Toyota (as you know) have recently stated that they are against plug-ins, because, firstly battery technology isn't there yet, and secondly, it doesn't really reduce pollution when the electricity used comes from coal.

Which is again quite a similar argument to your grief with ethanol. It's rather ironic to see your logic applied by Toyota to rubbish plug-in hybrids though ...
 
You've got a number of unrelated objections there, Heiko.  My time is limited this morning, but I can quickly deal with a few of them.

"So why go via zinc? This merely seems to be about storage and transmission. But car batteries could provide the same kind of storage capacity..."

No they eouldn't, and that's the issue; zinc provides far greater available storage, and allows energy to be stockpiled outside the vehicle.  The storage capacity of a kilogram of zinc is far higher than any available secondary cell.

"To generate hydrogen, there are other thermochemical cycles that can do greater than 50% efficiency, which would be hard to reach with zinc as an intermediate step."

But then you've got the 40% losses in the fuel cell, the expense and bulk of high-pressure tankage, and the ecological cost of leakage (transferring moisture far above the "cold trap" at the bottom of the stratosphere).  Not to mention that PEM FC's are around $5000/kW and need about 2 orders of magnitude in cost reduction to be practical...

"200 Wh per kg, and 90 W per kg are terrible numbers. 90 W per kg means 1000 kg to get 90 kW."

Remember, those are early-design cells designed to run a bus.  Units engineered for a car would have much more active material and somewhat higher specific power.

Not that you couldn't manage without further advances.  If I needed to travel 300 miles consuming 200 Wh/mi at the battery terminals (typical of many electrics), I'd only need 300 kg.  My average power would be about 12-15 kW; the difference between that and the 27 kW capacity of the Zn-air cells is what surge batteries are for.

"1. Zinc air fuel cells need considerable work for this to be viable commercially (or at least more viable than ordinary batteries)."

They don't compete in the same market.  The only conventional cells which have remotely competitive energy/mass are lithium-ion, and they're about an order of magnitude more expensive at the moment.

"With heat at 1200 degrees C, we should be able to generate electricity at the same efficiency as modern combined cycle natural gas fired power plants, make that 60%."

Solar heat is free; the figure of merit is not efficiency but cost.  I expect that zinc can be reduced to metal at much lower temperatures, but the product of the reaction would be carbon dioxide instead of carbon monoxide.  You could still sequester it but you wouldn't be able to use it to store energy or perform further syntheses.

Zinc oxide can also be reduced to metal using electricity from any source.  This makes it a worthwhile adjunct to wind and solar power and a component of not just the transport system but the entire energy network.

"2. The costs for generating solar heat at 1200 degrees C are somewhat uncertain and definitely not low."

Even if the solar-zinc cannot be done economically, the costs of conventional smelting (using biomass or otherwise) and electrolytic reduction are unaffected.  It would be terrific to be able to capture solar energy with 78% efficiency and make it run our vehicles, but this particular advance is not a sine qua non.
 
On char: do check out the link to Antal's work.

On zinc-air fuel cells: I am not sure what you are actually saying about storage. I gather that the storage capacity on board is 200 Wh/kg, and that that includes more than just the zinc, and that the zinc has to be surrounded by a solution that can't be done without.

Just like with hydrogen, it's not just the weight of the hydrogen alone.

You say it's an early design and it's for a bus and one could do better.

This seems terribly vague and rose coloured to me.

What performance data are to be expected in the future then, and what evidence do you have to substantiate such a claim?

I had already read your earlier comments on booster batteries in another threat somewhere. So, we'd have batteries, and a zinc-air fuel cell, and capacitors, and combined their performance/cost data wouldn't be all that great. To get people to buy these cars they should be able to climb a long slope without being forced into a crawl halfway up the hill for example.

On 78% efficiency: It's not an efficiency. That's quoted much lower in the press release, and they only expect 50% for a scaled-up plant (on unknown assumptions). The theoretical Carnot efficiency to electricity is some 95%, as pointed out by the Swiss researchers (going from 6000 to 300 K or so).

Efficiency vs cost: I couldn't agree more, it's just with ethanol and biomass where you suddenly lose all sight of cost as an important competitive issue.

If we could produce all petroleum requirements, plus some, on 13% of US land with switchgrass, and do that much cheaper than the solar zinc route, who'd care about the efficiency of conversion of sunlight to end use energy?

On hydrogen: I wasn't talking about fuel cells here, but about hydrogen production for other purposes, such as fertilisers, or more relevantly, liquid fuels.

Which is, incidentally, where with little technological progress I see things headed. Hydrogen is already increasingly used to upgrade heavy, sour petroleum.

Hydrocarbons are such convenient energy carriers, I figure they are the best hydrogen storage technology we've got.

From upgrading petroleum, we can go to upgrading coal and/or biomass, using hydrogen and process heat from renewable sources or nuclear power.

Synthetic fuels can easily be made at a cost that's below retail prices in Europe. At that price, plug-in hybrids or EV's or zinc fuel cells (+battery/+ultracapacitor) cannot currently compete, with most of this lack of competitiveness due to the price/performance characteristics of batteries(/zinc fuel cells/capacitors etc..).

So, without much technological progress, I find it easiest to envision a future where cars continue to sip fuels based on compounds of hydrogen and carbon (and optionally some oxygen).

For the near to medium term future, that's definitely what oil and car companies and governments are betting on.

For the longer term, there's also the "hydrogen economy", which, without technological progress on fuel cells and hydrogen storage, is just, well, a "vision" (just like batteries and zinc-air fuel cells, even though they currently don't get quite the same media attention - batteries are researched extensively, though, never mind the media attention, as there are many applications, where they are economic).
 
I mis-quoted myself; the 78% is the fraction of the energy of the zinc process coming from heat, the other 22% coming from the chemical energy of the carbon.

"What performance data are to be expected in the future then, and what evidence do you have to substantiate such a claim?"

I calculated the zinc fraction of the fuel cell by computing the mass-fraction of zinc required to produce the stated ampere-hour capacity; I came up with approximately 1/7.  To turn zinc metal into Zn(OH)2 requires 1/2 molecule O2 and 1 molecule H2O; the mass-fraction of water is about 1/4 that of the zinc.

The evidence I have is knowledge that such advances are not pushed into early prototypes, especially if they are not required.  Who'd put time and money into ultra-light spacers and high surface-area cathodes when they'd be a distraction from running your demo?  You do those things later, when you're trying to break into new markets and your track record is bringing in more investment or even revenue.

Electric Fuel claims 400 Wh/kg for their military cells.  And there are several others .  That would put the energy for a 300 mile trip in a 150 kg package, or let you get 600 miles out of the 300 kg pack.  Is that good enough for you?
 
BTW, I looked at Antal's page.  It's got a nice picture of what looks like an overgrown bomb calorimeter, but it doesn't mention anything about yield other than the "thermodynamic limit", whatever that is.

There were no links to the actual research.
 
The yield information's in the patent.
http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=/netahtml/srchnum.htm&r=1&f=G&l=50&s1=6,790,317.WKU.&OS=PN/6,790,317&RS=PN/6,790,317

On zinc:
Rechargeable batteries with aqueous electrolytes
Electrochimica Acta, Volume 45, Issues 15-16, 3 May 2000, Pages 2467-2482
Fritz Beck and Paul Rüetschi

There's little in the peer reviewed literature on zinc fuel cells, but this one was quite instructive, and expands on the trade-off mentioned on greencar congress, high energy density against low efficiency and low cycle life.

Cycle life and efficiency don't get mentioned by any of the manufacturers. In the above referenced article, you'll find this interesting paragraph:
"As shown in Table 3, the energy efficiency of zinc–air cells is quite low, about 50% or less, the main reason being the irreversibility (large difference between charge voltage and discharge voltage) of the oxygen electrode. This is why these projects were discontinued."

The zinc lobby, however, does mention it in their strategy for pushing zinc:
http://www.iza.com/zwo_org/Applications/Other_end_uses/znwpbattery.PDF

"Low efficiency (around 50%) – but this is offset by the
high specific energy and, in any case is comparable
with the system efficiencies offered by most fuel cells.
Also, traditional problems of electrical recharge – slow,
and few cycles, but see below."

So, it seems modestly higher energy density is traded against pretty low efficiency (and low cycle life, taking one electrode bathed in caustic solution out for recharge also seems a nightmare to me - this probably would require quite expensive refueling facilities).

I find it astounding that this issue does not get mentioned by the manufacturers.

http://ergosphere.blogspot.com/2005/07/why-hydrogen-is-no-route-to-renewables.html

I notice what you said about hydrogen. Plug in 50% for zinc-air and it starts to look distinctly similar to hydrogen on that count, and much worse than standard batteries.

I think you've always got to have a certain skepticism. If zinc is so good, why is it not used, or at least gets more attention than it does?

Usually the reason is that there are drawbacks that haven't been mentioned or that you haven't considered.

And in the case of zinc, I easily see those now. It's not a new technology, as you'll find when you read the above reference (it already got pushed in the 70's and abandoned).

So, zinc has a slightly higher energy density than batteries, but it has much lower power density, lower cycle life and efficiency comparable to hydrogen fuel cells, and the energy density is still around a factor 50 lower than for hydrocarbon fuels (which are one of the possible storage media for hydrogen).
 
Heiko, the low power density of zinc-air fuel cells can be overcome by pairing them in hybrid systems with ultracapacitors (which can output very high power for short periods of time, i.e. for passing or hill climbing). This is in fact what has been done in every actual application of zinc-air in vehicles I know of (such as Electric Fuel's zinc-air bus program).

My main question about zinc-air batteries is how does a car ownder refuel? Is there some way that the cathodes can be easily removed from the vehicle and replaced with fresh ones at a fueling station type operation? E-P also mentioned being able to recharge them with any electricity source (rather than solar heat). How does this process work? Are you simply using electricity to generate heat to fuel the chemical reaction? I thought the deal with zinc-air is that they could NOT be electrically recharged like other batterie (hence the reason I call them fuel cells and not batteries). Thanks for any clarification. Cheers (and keep up the discussion, this is very interesting).
 
As I mentioned elsewhere, Heiko does have a good point about the low efficiency of zinc-air cells.  (I'd wondered about the low cell voltage of the Electric Fuel units compared to the heat of formation of ZnO, but I put that down to the fact that the quoted figures were for 80% discharge where internal resistance would be rather high.)  This affects the cost calculations somewhat, but if the cells are competitive running a bus at today's diesel prices they're not going to get any worse.

There are several ways to regenerate metallic zinc from oxide (the hydroxide decomposes to oxide and water at 125°C):
1. Dissolve in acid, electrolyze to metallic zinc and oxygen.  (This is apparently how "electrolytic zinc" is refined.)
2. Reduce with carbon, producing metal and carbon dioxide.
3. Reduce with carbon and external heat, producing metal and carbon monoxide (usable for either fuel or synthesis).

"My main question about zinc-air batteries is how does a car ownder refuel?"

That depends one heck of a lot on the technology.  Electric Fuel's buses require the cells to be removed and the spent material replaced, which is a possibility for private vehicles if they have enough other battery capacity to allow a "reserve" a la motorcycles.  Another possibility is to find a way to replace the zinc from a slurry tank while the vehicle is in motion; IIRC, this has already been done more than 20 years ago.

Refilling a zinc car with two hoses (one to remove hydroxide slurry, the other to supply metal powder) would be somewhat more complex than filling with gasoline, but it would be a lot safer than anything using compressed gases.
 
Found on Green Car Congress:

"... all biofuels from all sources will remain a tiny addition to the existing sources of energy no matter what else we do." - Tad Patzek
 
Watthead,

yes, I was aware of that solution to the problem of low power density (it does add extra cost and weight though, and if it's just ultracapacitors, climbing a long hill you might slow down to a crawl halfway up).

From the reference I cited I gather that recharging can be done in situ, but that this leads to problems with "dendrites", unequal deposition of the zinc, and consequently very short cycle lives.

The two concepts as EP mentions are slurry exchange and outright exchange of the zinc electrode. Considering that the zinc is bathed in caustic solution this seems a little more tricky than filling a car with gasoline.
 
I rather disagree with Patzek:

Biofuels can make a substantial contribution, in fact, they are the best renewable solution for road and air transportation we've got with present technology.

Coal to liquids, powered by nuclear power, would probably be cheaper for the majority of demand (though for 10-20% of demand I think biomass could beat it).
 
Wow, great stats but i wonder if some of the people here head's are so far up their facts that they miss some basic points...

every dollar spent on opec oil funding people who want america to die...

so let me get this straight, 3 BILLION freaking gallons of waste oil could be made into bio-diesel, now where I come from, that is a hugh pile of cash to be made and spent in the good old USA and not given to the America haters. I hear you say, it's only .5% of the total market, we folks, I'd LOVE to have a chain of bio-diesel stations and grossing 200 million a year, I'd be happy with a 300k a yr salary...
 
PRFH, I'm all for using waste cooking oil for diesel fuel; I've been meaning to start burning it myself, but I've been a bit cramped for workspace and haven't been able to start trials yet.  And whatever else is going into landfills that could be converted to motor fuel instead - anything that can be converted from a liability to an asset is a good thing.

But 3 billion gallons per year isn't going to get us very far, even compared to a modest increase in fuel economy.  We just cannot afford not to develop new sources of energy, and we cannot afford the illusion that biofuels will save us and sit on our behinds.

FWIW, I started this blog with the intent of showing how to de-fund Wahhabism.  I mentioned that specifically in my first substantive post (The lynx and the hare), and made a point of it in the third (Starving the beast).  As I said:

We've created a monster, and the only thing we can do about it is to stop relying on foreign oil in general and Middle East oil in particular.  As most oil goes for transportation, we need to aim at the same cars and trucks which have been fuelling the profits of the auto industry.  This is not going to be an easy thing to do, but there is a point we have to keep in mind:  this is war, and war entails sacrifice.
 
It amazes me that this gets as much media play as it does - everyone I encounter takes it as truth that ethanol uses more energy than it consumes. Where does this come from? Find me one peer-reviewed scientific study. It reminds me of the global warming debate - not one peer-reviewed scientific study has been published refuting global warming but the media casts doubt on it in nearly every article.

A few thoughts on ethanol's energy balance:

1. The Pimental/Patzek studies have two factors that make ethanol negative that no one looks at - otherwise the Patzek study is nearly the same as the others:

a) Machinery - they include the steel and equipment used in farming (tell me a farmer won't have a combine if ethanol wasn't around - they even include the food the farmer/workers eat and fuel for getting to the plant, as if they wouldn't eat or drive otherwise)

b) Co-products - Ethanol plants make more than just ethanol and an energy "credit" needs to be included, which they don't.

2. Even if ethanol were net energy neutral, it has benefits:

a) Fuel blending flexibility to moderate prices when one is higher or lower than the other

b) Foreign oil displacement - only 17% of a gallon of ethanol is petroleum so every gallon saved 83% petroleum (55% of that is imported)

c) Air quality benefits when burned, reducing pollution (ask states who chose MTBE instead of ethanol whether that was a good choice)

3. Ethanol energy balances are debated because the possibility is there that it can generate more energy than it uses (i.e. photosynthesis) - you can't do that with oil. Oil is a net energy loser any way you calculate it.

4. Corn ethanol is a transition to cellulistic ethanol when this debate (those studies not withstanding) will cease - the energy balance is 3-5 x's positive and the inputs to a switchgrass are much less environmentally damaging. Could we have build the hybrid-gasoline car without the gasoline engine? No. Similarly we can't get to cellulistic ethanol without corn ethanol in the meantime.

5. Find me a better solution that can be implemented. Fuel economy standards would be my number one choice but it's not a solution - it buys time. We use so much energy that we're going to need everything we've got.

6. Don't try to tell me petroleum isn't subsidized. Let someone analyze that...Iraq? Saudi Arabia? Iran?

7. The two researchers are an inherently untrained and biased source.
 
"a) Machinery - they include the steel and equipment used in farming (tell me a farmer won't have a combine if ethanol wasn't around - they even include the food the farmer/workers eat and fuel for getting to the plant, as if they wouldn't eat or drive otherwise)"

Without the market for the corn, the farmer would not be in business and not have the equipment, no?

"2. Even if ethanol were net energy neutral, it has benefits:

a) Fuel blending flexibility to moderate prices when one is higher or lower than the other
"

That would still cost subsidy money.

However, ethanol is far from the best way to use corn for fuel.  As I've found in research elsewhere, burning a bushel of corn can yield up to 390,000 BTU of heat; the ethanol produced from that same bushel can yield only about 220,000 BTU.  Oil yields from regular hybrids are 3-5%, so a typical 56-lb bushel would provide between 1.7 and 2.8 pounds of oil with a net energy of 29,000 to 48,000 BTU (with some lost in processing to biodiesel).

We are better off burning the corn for space heat to free up natural gas and LPG, and then using the LPG and natural gas for motor fuel.  That would make it cheaper to heat homes too.

"b) Foreign oil displacement - only 17% of a gallon of ethanol is petroleum so every gallon saved 83% petroleum (55% of that is imported)"

Roughly 40% of the fuel value of ethanol is input as heat to the distillation process.  Some distillers use coal and The Panda Group is using bio-methane from manure digesters, but most burn natural gas or LPG.

Guess what we'll be very short of this winter due to hurricanes?  The President should already have declared a state of emergency and shut down all gas- and LPG-fired distillers.

"c) Air quality benefits when burned"

Those benefits vanished as automotive systems improved, and ethanol causes greater evaporative emissions than straight gasoline.

"4. Corn ethanol is a transition to cellulistic ethanol"

I've said this before, and I'll say it again:  nothing is going to eliminate the losses in conversion from either cellulose or starch to ethanol.  Further, vehicles are particularly inefficient at turning any kind of fuel into work.  We could get at least 50% more useful output by burning biomass to make electricity to run electric vehicles than we can by converting biomass to ethanol (perhaps as much as 3 times), and we get the further benefit of being able to drive those same vehicles using electricity made from any other source.

"7. The two researchers are an inherently untrained and biased source."

That's both the least coherent and most ironic statement I've ever seen about Pimentel et al.
 
If Brazil can be totally energy independent, by making ethanol out of sugar cane waste, and most of their GM vehicles run on Ethanol...what are we waiting for? Even the Ethanol Plant is powered by Ethanol, by ustilizing the waste of Sugar Cane.
 
IIUC, Brazil distills their cane ethanol by burning the "bagasse" (leftover cane stalks after pressing for juice).  This is about the same as Iogen's scheme (burning the lignin after hydrolyzing the cellulose to sugars and fermenting it).

Your statement about Brazil appears true, but it is misleading.  Brazil is a lightly populated country with a lot of acreage suitable for growing cane (the US is neither), and Brazil's oil resources have not been as heavily exploited and depleted as the USA's.  Further, Brazil's cane-ethanol success comes at the expense of "mining" its natural rain-forest capital (like the palm-oil plantations being put into Malaysia and Indonesia).  The USA could not use the same methods as Brazil even if it were advisable to do so, and it certainly is not.
 
How about using solar panels instead?
 
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