Ethanol Deception - Is It Really Better Than Gasoline?

[Ivan Seeking]

Ah, now we change the argument.

As I stated earlier, bio from algae was not competitive until we reached today's prices. At some price for fuel, it would be worth growing algae in your pool and scooping it out with a net. The CO2 requirements were to provide enough growth to be economically viable.

 

[Aether]

Ah, now we change the argument.

Do you think that I am being unfair to you in some way? You acknowleded above that one acre-year of farm land is required to produce 380 gallons of ethanol if coal is also used as an input, so that issue is now resolved.

As I stated earlier, bio from algae was not competitive until we reached today's prices. At some price for fuel, it would be worth growing algae in your pool and scooping it out with a net. The CO2 requirements were to provide enough growth to be economically viable.

Okay, but I didn't see that stipulation anywhere in your argument before now. I don't doubt that you can produce a limited amount of biodiesel at a reasonable price using dense CO2 from coal plants as an input. However, this process is not scalable because there is a limited supply of dense CO2.

 

[Ivan Seeking]

Do you think that I am being unfair to you in some way? You acknowleded above that one acre-year of farm land is required to produce 380 gallons of ethanol if coal is also used as an input, so that issue is now resolved.

Sure, if we want to build 600 coal plants ethanol is viable at that rate of production. Have you figured out that your 150% is the same as my 30%?

Okay, but I didn't see that stipulation anywhere in your argument before now. I don't doubt that you can produce a limited amount of biodiesel at a reasonable price using dense CO2 from coal plants as an input. However, this process is not scalable because there is a limited supply of dense CO2.

I said early on that much of the literature focuses on making algae competitive at much lower prices, which it was not, but at today's prices the story is quite different. And just for the record, I have been getting viable yields under far less than ideal circumstances - only about 60% of the light that things should have, and no CO2 added at all, only aeration. Also keep in mind that we have lots of people working on this right now, and some estimates are as high as 20,000 gallons per acre-year - some people claim to be getting yields this high [which would only represent about a 10% conversion efficiency, same as solar cells]. But even the lowest estimates are viable at today's prices.

If I'm wrong, it will cost me dearly.

 

[Ivan Seeking]

IMO, it is imperative that we select the best path available to us, and clearly bio from algae is the best option by far. Ethanol cannot solve the energy problem with technology that exists today, and I have learned to quit betting the farm on what we will be able to do in the future - the future is often not what is promised.

 

[Ivan Seeking]

Oh yes, one last thought and then I'm out of this one: We already have a tremendous demand for diesel from the trucking and other industries, so bio has a market before we even talk about cars. And no doubt ethanol will continue to help reduce the demand for petro for many years to come, so the corn farmers can relax for at least a decade or more.

Edit: Okay I lied, one more last thought: If one studies the algae option for a year and half as I have, it becomes apparent that some concerns mentioned earlier are not an issue. But at this point we are into proprietary information and I have to be selfish to protect my own interests.

 

[joema]

The January 2007 issue of Scientific American had a detailed study on the viability of corn ethanol. It concluded if 100% of the U.S. corn crop was diverted to ethanol production, it would power only a small fraction of the nation's vehicles: http://www.nelson.wisc.edu/outreach/biofuels/readings/isethanolforthelonghaul.pdf

So aside from the net energy balance problem (whether it takes more energy to produce corn ethanol than the final product contains), there's simply not enough acreage at current yield rates to provide sufficient ethanol to make a significant difference. That's even if all corn food production ceased in favor of ethanol production.

Celulosic conversion in theory has higher yield and net energy efficiency, but it's unknown whether this can be done on the gigantic industrial scale required: http://en.wikipedia.org/wiki/Cellulosic_ethanol

 

[turbo]

Ethanol as fuel is a sop to ADM and others to subsidize their crop prices. I was an industrial training consultant in the 1990s and visited a plant owned by Quantum Chemicals in Iowa. The plant (IMO) would not and could not ever be self-sufficient and had to rely on US subsidies to remain in operation. The US taxpayers are being soaked by a lot of players in the alternate fuel market.

 

[Ivan Seeking]

The January 2007 issue of Scientific American had a detailed study on the viability of corn ethanol. It concluded if 100% of the U.S. corn crop was diverted to ethanol production, it would power only a small fraction of the nation's vehicles: http://www.nelson.wisc.edu/outreach/biofuels/readings/isethanolforthelonghaul.pdf

So aside from the net energy balance problem (whether it takes more energy to produce corn ethanol than the final product contains), there's simply not enough acreage at current yield rates to provide sufficient ethanol to make a significant difference. That's even if all corn food production ceased in favor of ethanol production.

Celulosic conversion in theory has higher yield and net energy efficiency, but it's unknown whether this can be done on the gigantic industrial scale required: http://en.wikipedia.org/wiki/Cellulosic_ethanol

I want to thank you for introducing me to the Aquatic Species Program. Note my new avatar - you killed the alien!

I have started a new company that will produce biodiesel from algae, and things are coming along very nicely.

 

[glondor]

What is involved in the algae process? Do you need to own your own lake?? Or is the process a factory type operation? Just curious.

 

[joema]

Biodiesel from algae: http://www.unh.edu/p2/biodiesel/article_alge.html

U.S. Aquatic Species Program (research to produce biofuels from algae): http://en.wikipedia.org/wiki/Aquatic_Species_Program

Overview of algaculture (farming from algae): http://en.wikipedia.org/wiki/Algaculture

 

[Ivan Seeking]

We know very well how to produce fuel from algae, the key is to develope methods and systems to do this as cost effectively as possible. Since the cost of fuel is now high enough to justify pursuing the technology, we seem to be at the point where many people are keeping their bioreactor designs a secret - it is now a competitive industry and most people working on this won't say much. But I will say that there are thousands of strains of algae - we don't know much about many of the best candidates for fuel production - and probably several dozen critical design concepts.

 

[K.J.Healey]

A couple of questions:
Does anyone know how much energy is spent converting crude fuel to processed gasoline? What about corn, sugar beets, or algea to something that is in its final combustible form?

I'm just wondering how many alternate styles are more: "We produced 1 gas-gallon equivalent of fuel made from some high-yield crop and it only cost 2 gas-gallon equivalents from our local coal/gas power plant in energy."

I'm sure some of these methods have to be easier and more energy efficient than others to converto to a burnable fuel?



And as a side note, has hydrogen been completely removed from our thoughts? I always thought the best long-term solution was a "nuclear" powered car. Nuclear power plant's grids used for electrolysis to make hydrogen to be stored and distributed. I know they calimed for a while that the "biggest" issue was a way of storing it safely. But I remember back in college about 5-6 years ago (I went to Kettering / GMI Tech) we had a talk (I think I can talk about this...) from GM I believe, where they, or someone, had developed a way to store hydrogen in reusable carbon plates. It was basically you could reuse the material to soak in hydrogen, and then dissolve it in your drivetrain somewhere to release the gas hydrogen. I believe both the plates and the chemical used to dissolve were both reusable in some sort of way.

 

[Ivan Seeking]

A couple of questions:
Does anyone know how much energy is spent converting crude fuel to processed gasoline? What about corn, sugar beets, or algea to something that is in its final combustible form?

This is the fuel chain efficiency, and for petro I believe the efficiency is about 80% for gasoline. For corn ethanol the efficiency is usually cited as about 30%. I know sugar beets and cane are better but I don't know the numbers by memory. Processing of biodiesel from algae is commonly cited as about 70% efficient - for every 100 BTUs worth of fuel, about 30 BTUs was spent growing the algae and processing the fuel.

If you read the rest of this thread, you will see that we hash this out pretty well.

I'm just wondering how many alternate styles are more: "We produced 1 gas-gallon equivalent of fuel made from some high-yield crop and it only cost 2 gas-gallon equivalents from our local coal/gas power plant in energy."

Some people claim that corn ethanol has a net zero gain.

And as a side note, has hydrogen been completely removed from our thoughts? I always thought the best long-term solution was a "nuclear" powered car. Nuclear power plant's grids used for electrolysis to make hydrogen to be stored and distributed. I know they calimed for a while that the "biggest" issue was a way of storing it safely. But I remember back in college about 5-6 years ago (I went to Kettering / GMI Tech) we had a talk (I think I can talk about this...) from GM I believe, where they, or someone, had developed a way to store hydrogen in reusable carbon plates. It was basically you could reuse the material to soak in hydrogen, and then dissolve it in your drivetrain somewhere to release the gas hydrogen. I believe both the plates and the chemical used to dissolve were both reusable in some sort of way.

Hydrogen can be processed from algae, so I see biodiesel from algae as a step towards hydrogen. However, for now, and until the hydrogen from algae process is more fully developed, IMO the best solution is biodiesel.

I don't think we could build enough nuke plants to replace petro for about 200years, even if we started building them today, which we won't.

 

[joema]

...has hydrogen been completely removed from our thoughts? I always thought the best long-term solution was a "nuclear" powered car. Nuclear power plant's grids used for electrolysis to make hydrogen to be stored and distributed. I know they calimed for a while that the "biggest" issue was a way of storing it safely...

The biggest problem with hydrogen is NOT storing it safely. There are various solutions to that.

Rather the problem is hydrogen is not an energy source, like oil is. Rather it's an energy transport device, and it takes lots of energy to create hydrogen. We call our current situation an "energy crisis" because of the lack of clean energy, not because we're oversupplied with energy, just can't think of how to transport it.

If you had a vast supply of energy, whether fission, fusion or some other source, hydrogen would be one of several possible ways to use that for transportation. The problem is we don't have such a supply, and the inefficiencies and implementation costs of hydrogen make the core problem (lack of clean, renewable energy) worse.

As Ivan pointed out, it would take thousands of new fission plants to create enough hydrogen for the world transportation sector:

The world consumes 100 quadrillion BTUs of transportation energy per year, (2.9E16 watt hours). The hydrogen production, transport and fuel cell end-to-end efficiency is roughly 30%. A 1GW nuclear reactor produces 8.76E12 watt hours per year. So very roughly, you'd need (2.9E16 * 3.33) / 8.76E12 or 11,023 new 1GW fission reactors.

To provide 1/2 world transportation energy you'd need about 6,000 new reactors. To provide 1/2 of US transportation energy (roughly 4.39E15 watt hrs) you'd 1,670 new reactors. Currently there are about 100 reactors on line in the US, and they're all occupied producing utility energy.

 

[Aether]

And just for the record, I have been getting viable yields under far less than ideal circumstances - only about 60% of the light that things should have, and no CO2 added at all, only aeration.

By my calculations, at least 18,000 cubic meters of fresh air per gallon of biodiesel would be required to produce algae using aeration alone to supply the co2; e.g., 16 moles of c12h26 per gallon of biodiesel = 193 moles of CO2 required per gallon = 8.45kg co2/gal = 21,125kg of air per gallon @ 400ppm CO2 in air = 18k m^3 of air at 1.177kg/m^3.

What is your estimate for the energy cost of circulating 18,000 cubic meters of air through an algae bed per gallon of biodiesel produced? Ideally, forcing this much air under a layer of water of any given depth should cost about: 18k m^3 air X 10kPa/m pressure drop = 180MJ/m; so, what depth should we assume for the algae bed? You will need a very thin algae bed in order to minimize this cost, but so far you have only quoted biodiesel production in terms of acre-years (a three dimensional term); but what really seems to matter if you are planning to use aeration is the rate of biodiesel production per cc-year of an algae bed (a four dimensional term). Also, this raises an issue of how does this rate of production decline with depth; e.g., as you get farther (deeper) from the sunlight?

Of course there will be some evaporation of water (depending on the relative humidity of the fresh air) and hydrocarbon into the air, so:

What is your estimate for the average cost of hydrocarbon emissions to the forced air, and for cleaning this up once you are done with it? Do you plan to incinerate the HC emission, catalytically convert it, try to reclaim it somehow, or just vent it into the atmosphere?

And, what is your estimate for the average cost of replacing water lost to evaporation?

I have learned to quit betting the farm on what we will be able to do in the future - the future is often not what is promised...If one studies the algae option for a year and half as I have, it becomes apparent that some concerns mentioned earlier are not an issue. But at this point we are into proprietary information and I have to be selfish to protect my own interests...I have started a new company that will produce biodiesel from algae, and things are coming along very nicely.

I wish you the best of luck with your new company, but you really should not be raising issues here (especially issues that you have a personal financial interest in) unless you are prepared to defend your claims. If you aren't prepared to defend your claims, then you should withdraw them until such time as you are prepared to defend them.

This is the fuel chain efficiency, and for petro I believe the efficiency is about 80% for gasoline.

This is roughly accurate for the average "Wells-to-Pump" (WTP) energy efficiency of gasoline production.

For corn ethanol the efficiency is usually cited as about 30%.

This is roughly accurate for the "Net Energy" of ethanol production. The WTP energy efficiency of ethanol production is 143% if the Net Energy is 30% then 143%=(100%/(100%-30%)).

Processing of biodiesel from algae is commonly cited as about 70% efficient - for every 100 BTUs worth of fuel, about 30 BTUs was spent growing the algae and processing the fuel.

If the Net Energy of biodiesel production is 70%, then the WTP energy efficiency of biodiesel production from algae is 333%=(100%/(100%-70%)).

Maybe that is a reasonable estimate for algae grown with CO2 from a coal-fired power plant under good climate conditions, I don't know; but I would doubt such a high estimate for algae grown under less favorable conditions such as with aeration.

 

[chemisttree]

And as a side note, has hydrogen been completely removed from our thoughts?...

...But I remember back in college about 5-6 years ago (I went to Kettering / GMI Tech) we had a talk (I think I can talk about this...) from GM I believe, where they, or someone, had developed a way to store hydrogen in reusable carbon plates. It was basically you could reuse the material to soak in hydrogen, and then dissolve it in your drivetrain somewhere to release the gas hydrogen. I believe both the plates and the chemical used to dissolve were both reusable in some sort of way.

You might want to glance at this thread.

https://www.physicsforums.com/showthread.php?t=170679

The algae to oil process is very interesting. The oil will no doubt be edible and, once refined, the price will naturally follow that of the other edible oils. In the event the oil is not of an edible nature, the price will follow that of the other fats (castor oil, jojoba, emu, etc...) that it is most closely related to from a chemical point of view. Can that price be justified without some government support?

 

[Ivan Seeking]

Maybe that is a reasonable estimate for algae grown with CO2 from a coal-fired power plant under good climate conditions, I don't know; but I would doubt such a high estimate for algae grown under less favorable conditions such as with aeration.

All worthy questions, but as I said, at this point the industry is competitive.

I don't feel compelled to give away 18 months worth of work in order to justify creating interest. A review of the industry will reveal that many approaches are considered and each has it own problems and benefits. You will also find that most people will not give away specific information. This is normal in any competitive industry. That's why I had to do 18 months of homework.

Most schemes utilize a number of systems, such as in this application.
http://xldairygroup.com/pressrelease.cfm?ContentKey=620

 

[Aether]

All worthy questions, but as I said, at this point the industry is competitive.

I don't feel compelled to give away 18 months worth of work in order to justify creating interest.

Okay, that's why I didn't ask before; but then you referenced this thread here: https://www.physicsforums.com/showpost.php?p=1371139&postcount=67 and said

The problem is that there is only one crop that can produce enough biofuel per acre-year to satisfy the need for crude oil: Algae. Any other option will require more land for fuel crops than we have land...I have started a company to produce biodiesel from algae and am using 7500 gallons per acre-year as a standard.

If you want to present these as claims then you will have to defend them. If you aren't ready and/or willing to defend these claims, then you could preface your remarks with something like "I think...", or "I am investigating the possibility that maybe...", or something like that. Or, you could cite a credible reference that makes (and substantiates) the same claims.

 

[Aether]

Most schemes utilize a number of systems, such as in this application.
http://xldairygroup.com/pressrelease.cfm?ContentKey=620

This is interesting, and I wish these people the best of luck with their project, but they seem to have some rather high expectations for their millk cows: 13,333 gallons of ethanol, 3,333 to 4,000 gallons of biodiesel, and 2,800 gallons of milk per cow-year!

That's 1.521 gallons of ethanol per cow per hour, 24hrs/day! How are they doing to do that?!?

When fully built, the $260 million ag-industrial complex planned by the XL Dairy Group will produce 100 million gallons of ethanol, 25 million to 30 million gallons of biodiesel fuel and 21 million gallons of milk a year...The firm will move in the first of 2,500 dairy cows in about three months to begin milk production, Corderman said. Also within three months, the company plans to begin construction on the second phase of the dairy, which will eventually house about 7,500 milk cows.

 

[joema]

there is only one crop that can produce enough biofuel per acre-year to satisfy the need for crude oil: Algae. Any other option will require more land for fuel crops than we have land..

...If you want to present these as claims then you will have to defend them...

http://en.wikipedia.org/w/index.php?title=Biodiesel&oldid=142744380

It's basic math. The world consumes about 100 quadrillion BTU of transportation energy per year, much of which comes from crude oil. It's about 30 billion barrels per year (1.26 trillion gallons or 4.8E12 liters).

Corn ethanol yield is about 400 gallons/acre, sugar cane about 700 gal/acre, switchgrass about 800 gal/acre. Ethanol contains about 76,000 BTU/gal, so:

Acreage required to provide world transportation energy from corn ethanol: (100 quadrillion BTU / 76,000 BTU/gal) / 400 gallons/acre = 3.3 billion acres, or 13.3 million square km.

Acreage required to provide world transportation energy from sugar cane: 1.9 billion acres (7.7 million square km)

The entire North American continent is only about 26 million square km, so about 1/2 of the continent would be required using corn ethanol.

By contrast the biodiesel contains about 120000 BTU/gal, and yield/acre using algae feedstock is about 5000 gal/acre. So it has roughly 20x the energy yield per acre as corn ethanol, requiring about 1/20th the area.

 

[Aether]

there is only one crop that can produce enough biofuel per acre-year to satisfy the need for crude oil: Algae. Any other option will require more land for fuel crops than we have land..

...If you want to present these as claims then you will have to defend them...

It's basic math...Acreage required to provide world transportation energy from corn ethanol: (100 quadrillion BTU / 76,000 BTU/gal) / 400 gallons/acre = 3.3 billion acres, or 13.3 million square km.

Acreage required to provide world transportation energy from sugar cane: 1.9 billion acres (7.7 million square km)

The entire North American continent is only about 26 million square km, so about 1/2 of the continent would be required using corn ethanol.

Then what basic math shows here is that we have more than enough land in North America alone to produce enough corn ethanol to satisfy world transportation energy demand, right?

By contrast the biodiesel contains about 120000 BTU/gal, and yield/acre using algae feedstock is about 5000 gal/acre. So it has roughly 20x the energy yield per acre as corn ethanol, requiring about 1/20th the area.

Maybe so, but farm land is not the only input required for biofuel production. Concentrated CO2 is an essential input for economical biodiesel production from algae, and this is a scarce resource. Aeration can provide the CO2 required for biodiesel production from algae, but probably not cost effectively.

...ethanol constitutes 99% of all biofuels in the United States. -- http://rael.berkeley.edu/EBAMM/FarrellEthanolScience012706.pdf

It is interesting to note that corn crops not only utilize sunlight for photosynthesis, but they also utilize wind power for aeration.

 

[joema]

Then what basic math shows here is that we have more than enough land in North America alone to produce enough corn ethanol to satisfy world transportation energy demand, right?

That's half the total land surface area, not all of which is arable. Much of the land area is mountainous or otherwise unsuited for crops.

Arable land in North America is about 1/8th the total land surface area, forests about 1/3.

If you mowed down all the forests to plant corn, and didn't use any corn for food production, plus diverted all other food crop acreage to corn, it still wouldn't produce enough ethanol.

This was discussed in the January 2007 Scientific American. They concluded if 100% of current U.S. corn production was diverted to ethanol production, it would supply only a tiny fraction of U.S. transportation energy. The same is true on a global scale.

 

[Aether]

That's half the total land surface area, not all of which is arable. Much of the land area is mountainous or otherwise unsuited for crops.

Arable land in North America is about 1/8th the total land surface area, forests about 1/3.

If you mowed down all the forests to plant corn, and didn't use any corn for food production, plus diverted all other food crop acreage to corn, it still wouldn't produce enough ethanol.

Maybe so, but that's not what you said before.

This was discussed in the January 2007 Scientific American. They concluded if 100% of current U.S. corn production was diverted to ethanol production, it would supply only a tiny fraction of U.S. transportation energy.

Your example above requires North America to supply world demand for transportation energy, but the Scientific American article is talking about U.S. corn production satisfying U.S. demand for transportation energy.

The same is true on a global scale.

Where does the Scientific American article say that?

It would be nice if corn ethanol alone could meet the current world demand for transportation energy, but I agree that it can't. U.S. energy security requires that we reduce our dependence on foreign oil. This can be done by a combination of conservation and alternative energy production. Corn ethanol is playing an increasingly significant role as an alternative energy source, and it already plays a far more significant role than biodiesel from algae (if aeration is required) will ever play.

 

[joema]

Your example above requires North America to supply world demand for transportation energy, but the Scientific American article is talking about U.S. corn production satisfying U.S. demand for transportation energy.

My example does NOT require North America to supply world transportation energy, it was simply a familiar geographic illustration. E.g, the same acreage would occupy 134% of Europe, or 100% of Antarctica or 75% of South America. It doesn't mean you'd be growing corn in Antarctica. It simply illustrates the poor yield of current feedstocks requires continent-size acreage to produce enough biofuel to replace current sources.

Where does the Scientific American article say that?

Physics doesn't change when crossing a national border. The yield/acre may change modestly based on climate, but not sufficiently to alter applying the conclusions to a global scale. If the goal is actually solving the problem (vs making a marginal contribution) conventional biofuel feedstocks are very inadequate from a areal yield standpoint, no matter which ones are considered, or where they are grown.

U.S. energy security requires that we reduce our dependence on foreign oil. This can be done by a combination of conservation and alternative energy production. Corn ethanol is playing an increasingly significant role as an alternative energy source, and it already plays a far more significant role than biodiesel from algae...

The question is what alternative energy source is scalable to the vast industrial level to make a major difference.

Ivan's point was the yield-per-acre of all other current feedstocks (besides algae) is too low to achieve this. That doesn't mean corn, soy, etc. can't be a marginal contributor. But if you want to actually solve the problem, it requires much higher yield per acre.

It's possible there may be unforeseen problems with biodiesel production from algae that prevent scaling it up sufficiently, but at least the areal yield is there. By contrast other conventional feedstocks cannot possibly provide enough energy in the available acreage.

 

[Aether]

My example does NOT require North America to supply world transportation energy, it was simply a familiar geographic illustration. E.g, the same acreage would occupy 134% of Europe, or 100% of Antarctica or 75% of South America. It doesn't mean you'd be growing corn in Antarctica. It simply illustrates the poor yield of current feedstocks requires continent-size acreage to produce enough biofuel to replace current sources.

What I am saying is that your example and the Scientific American article aren't comparable. You should restate your example in the same context as the Scientific American article if you want to compare the two.

Physics doesn't change when crossing a national border. The yield/acre may change modestly based on climate, but not sufficiently to alter applying the conclusions to a global scale.

Per capita energy consumption for transportation does.

If the goal is actually solving the problem (vs making a marginal contribution) conventional biofuel feedstocks are very inadequate from a areal yield standpoint, no matter which ones are considered, or where they are grown.

Maybe so. In that case, energy conservation may have to make up the difference.

The question is what alternative energy source is scalable to the vast industrial level to make a major difference.

Ivan's point was the yield-per-acre of all other current feedstocks (besides algae) is too low to achieve this. That doesn't mean corn, soy, etc. can't be a marginal contributor. But if you want to actually solve the problem, it requires much higher yield per acre.

Either that, or effective energy conservation.

It's possible there may be unforeseen problems with biodiesel production from algae that prevent scaling it up sufficiently, but at least the areal yield is there.

The problems with biodiesel production from algae are not unforeseen. The aquatic biospecies program was closed down in 1998, and their website says that this subject is no longer a research priority. There has been no evidence presented here to show that there is any real yield (e.g., positive net energy) for biodiesel from algae grown using aeration.

By contrast other conventional feedstocks cannot possibly provide enough energy in the available acreage.

The real contrast here is that "...ethanol constitutes 99% of all biofuels in the United States", and biodiesel from algae grown using aeration contributes nothing.

 

[joema]

What I am saying is that your example and the Scientific American article aren't comparable. You should restate your example in the same context as the Scientific American article if you want to compare the two.

The issue which Scientific American highlighted (limited ethanol yield from current feedstocks making it impossible to supply a major % of U.S. transportation energy) also applies on a global basis for exactly the same reason.

Whether on a U.S. or global basis, there's a given need for transportation energy. Likewise on a U.S. or global basis, there's a given amount of available, arable land to produce this. For the exact same reason that ethanol cannot provide a major % of U.S. transportation energy, it likewise cannot provide a major % of world transportation energy: the yield per acre is too low for the available land and energy requirement.

Ivan's point was only a much higher yield feedstock is scalable to meet the necessary demand, and algae is one of the only (maybe THE only) feedstock with the necessary yield.

Per capita energy consumption for transportation does.

Per capita energy consumption is not relevant to the issue, which is whether any biofuel can be scaled upward sufficiently to supply a major % of U.S. or global transportation energy. It's not per-capita consumption that matters, it's total consumption.

In that case, energy conservation may have to make up the difference.

The difference is VASTLY too much for conservation to make up the difference. That doesn't mean conservation is wrong or shouldn't be used, only that it's inadequate to compensate for the insufficient yield from current biofuel feedstocks.

As the Scientific American article highlighted, ethanol (for example) can only supply a few % of U.S. transportation energy. On a global basis, the situation is similar. This means conservation would have to make up at least 80% of the current consumption, which is about 100 quadrillion BTU/year. It's simply not possible to reduce global transportation energy consumption by 80% via normal conservation measures within a timeframe meaningful to the problem. It would require a total restructuring of all society, akin to an asteroid hitting the earth, a nuclear war, or a global plague which decimates humankind.

The real contrast here is that "...ethanol constitutes 99% of all biofuels in the United States", and biodiesel from algae grown using aeration contributes nothing.

The issue is NOT what % of transportation energy is currently supplied by a given biofuel feedstock. Rather it's what biofuel feedstock (if any) can be scaled to the gigantic industrial level required to supply a major % of U.S. or world transportation energy. With ethanol from corn, soy, switchgrass, etc. it's clearly impossible. Algae at least is theoretically possible from a yield standpoint, plus can be grown on non-arable land so it doesn't displace existing crops.

That doesn't mean biodiesel from algae is the solution or is guaranteed to work. However ethanol from conventional feedstocks are guaranteed to NOT work, i.e, provide a major % of U.S. or global transportation energy.

 

[Aether]

Ivan's point was only a much higher yield feedstock is scalable to meet the necessary demand, and algae is one of the only (maybe THE only) feedstock with the necessary yield.

As far as I know algae has only been shown to produce a high yield per acre-year under laboratory conditions where it is was grown in a sealed container, in an ideal climate (good insolation), and supplied with concentrated CO2 from the exhaust of a coal-fired power plant. I expect that corn, and just about any other crop, would produce a spectacularly increased yield per acre-year under similar conditions. It seems reasonable to try and exploit available sources of concentrated CO2 for biofuel production, perhaps using algae, but this is not what Ivan is trying to do. He is trying to grow algae using aeration. Unless and until someone here explicitly claims, and then cites a credible reference (or makes a plausible argument) to substantiate that claim, that there is a positive net energy balance for biodiesel production from algae grown using aeration, then we should dismiss that claim. Don't you agree?

Per capita energy consumption is not relevant to the issue, which is whether any biofuel can be scaled upward sufficiently to supply a major % of U.S. or global transportation energy. It's not per-capita consumption that matters, it's total consumption.

The SA article presents an analysis of U.S. biofuel supply and demand, but not world biofuel supply and demand. This website presents data showing that there is a great variation in per capita energy consumption from one country to another: http://www.hubbertpeak.com/nations/percapita.htm. It is not reasonable to assume that the analysis presented in the SA article for U.S. biofuel supply and demand should also apply to the world as a whole.

The difference is VASTLY too much for conservation to make up the difference.

When the petroleum supply finally runs out, conservation can and will make up the difference. .

That doesn't mean conservation is wrong or shouldn't be used, only that it's inadequate to compensate for the insufficient yield from current biofuel feedstocks.

Ha ha...conservation is infinitely adequate for the task, I assure you.

As the Scientific American article highlighted, ethanol (for example) can only supply a few % of U.S. transportation energy. On a global basis, the situation is similar.

Per capita energy consumption in the U.S. is 697 times greater than it is in Afghanistan for example, and average per capita energy consumption in the rest of the world is several times lower than it is in the U.S.. So, again, it is not reasonable to assume that the analysis presented in the SA article for U.S. biofuel supply and demand should also apply to the world as a whole.

This means conservation would have to make up at least 80% of the current consumption, which is about 100 quadrillion BTU/year. It's simply not possible to reduce global transportation energy consumption by 80% via normal conservation measures within a timeframe meaningful to the problem.

Oh yes it is possible, and it will happen when the oil runs out. btw, I am not just talking about "normal" (I assume that you mean "voluntary") conservation measures, but also involuntary conservation measures and technological advances.

It would require a total restructuring of all society, akin to an asteroid hitting the earth, a nuclear war, or a global plague which decimates humankind.

Good. The sooner the better. I doubt that the advance of science in general and Moore's law in particular will be greatly hindered by such a restructuring. So what if we all wind up either riding bicycles or busses to work at some point in the future?

The issue is NOT what % of transportation energy is currently supplied by a given biofuel feedstock. Rather it's what biofuel feedstock (if any) can be scaled to the gigantic industrial level required to supply a major % of U.S. or world transportation energy. With ethanol from corn, soy, switchgrass, etc. it's clearly impossible.

I will not discuss "world transportation energy" with you using only the SA article as a basis. It is not reasonable to assume that the analysis presented in the SA article for U.S. biofuel supply and demand should also apply to the world as a whole.

Algae at least is theoretically possible from a yield standpoint, plus can be grown on non-arable land so it doesn't displace existing crops.

You keep talking in terms of "areal yield" and ignoring what I have said about the requirements for concentrated CO2 vs. aeration to produce biodiesel from algae. I am quite sure that fission has a vastly superior "areal yield" to biodiesel from algae in terms of kWh/acre-year. Don't you agree?

That doesn't mean biodiesel from algae is the solution or is guaranteed to work.

Ivan claims otherwise. He is claiming that algae can satisfy the need for crude oil. I have asked him to preface his remarks with "I think", or something like that, but so far he hasn't done that. So, I reject his claims as they stand. Don't you agree?

there is only one crop that can produce enough biofuel per acre-year to satisfy the need for crude oil: Algae.

However ethanol from conventional feedstocks are guaranteed to NOT work, i.e, provide a major % of U.S. or global transportation energy.

Ethanol displaces a marginal % of petroleum consumption which is useful, and this will become increasingly important as the supply of petroleum dwindles away. Who has claimed otherwise?

 

[Astronuc]

The anaerobic bacterium C. ljungdahlii, recently discovered in commercial chicken wastes, can produce ethanol from single-carbon sources including synthesis gas, a mixture of carbon monoxide and hydrogen that can be generated from the partial combustion of either fossil fuels or biomass. Use of these bacteria to produce ethanol from synthesis gas has progressed to the pilot plant stage at the BRI Energy facility in Fayetteville, Arkansas.

http://en.wikipedia.org/wiki/Clostridium#Commercial_uses

http://www.brienergy.com/pages/process01.html

 

[Astronuc]

http://www.nytimes.com/2007/09/30/business/30ethanol.html

NEVADA, Iowa, Sept. 24 — The ethanol boom of recent years — which spurred a frenzy of distillery construction, record corn prices, rising food prices and hopes of a new future for rural America — may be fading.

Only last year, farmers here spoke of a biofuel gold rush, and they rejoiced as prices for ethanol and the corn used to produce it set records.

But companies and farm cooperatives have built so many distilleries so quickly that the ethanol market is suddenly plagued by a glut, in part because the means to distribute it have not kept pace. The average national ethanol price on the spot market has plunged 30 percent since May, with the decline escalating sharply in the last few weeks.

“The end of the ethanol boom is possibly in sight and may already be here,” said Neil E. Harl, an economics professor emeritus at Iowa State University who lectures on ethanol and is a consultant for producers. “This is a dangerous time for people who are making investments.”

While generous government support is expected to keep the output of ethanol fuel growing, the poorly planned overexpansion of the industry raises questions about its ability to fulfill the hopes of President Bush and other policy makers to serve as a serious antidote to the nation’s heavy reliance on foreign oil.

And if the bust becomes worse, candidates for president could be put on the spot to pledge even more federal support for the industry, particularly here in Iowa, whose caucus in January is the first contest in the presidential nominating process.

Two problems with corn-based ethanol - it's subject to fluctations in price, so price stability is an issue, and since more corn (one of two basic grains for animals raised for food) is used for ethanol, the price for foods based on corn increases.

 

[turbo]

http://www.nytimes.com/2007/09/30/business/30ethanol.html


Two problems with corn-based ethanol - it's subject to fluctations in price, so price stability is an issue, and since more corn (one of two basic grains for animals raised for food) is used for ethanol, the price for foods based on corn increases.

There are people in this state pushing the sales of corn-fed stoves to heat homes. That's a pretty dumb thing to buy into, since corn has lots of better uses, and an increase in anyone of them can drive the price of corn (for heating) through the roof, as can a poor crop year. In a state that is almost completely forested, it's a no-brainer to get an efficient wood stove for heating, but still, people are buying corn-fueled stoves. Duh! People want to reduce their dependence on oil products price-controlled by OPEC and the domestic oil cartel, only to rush into the clutches of ConAgra, ADM, and other giant corporations controlling domestic agriculture.

 

[Astronuc]

Study: Ethanol Worse for Climate Than Gasoline

http://www.npr.org/templates/story/story.php?storyId=18784732

All Things Considered, February 7, 2008 · At first blush, biofuels such as corn ethanol and soybean diesel seem like they would be great from the standpoint of global warming. The crops soak up carbon dioxide from the atmosphere as they grow, and that balances out the carbon dioxide they produce when they're burned. But until now, nobody has fully analyzed all the ripple effects of this industry. And Tim Searchinger, a visiting scholar at Princeton University, says those effects turn out to be huge.

"The simplest explanation is that when we divert our corn or soybeans to fuel, if people around the world are going to continue to eat the same amount that they're already eating, you have to replace that food somewhere else," Searchinger says.

Searchinger and his colleagues looked globally to figure out where the new cropland is coming from, as American farmers produce fuel crops where they used to grow food. The answer is that biofuel production here is driving agriculture to expand in other parts of the world.

"That's done in a significant part by burning down forests, plowing up grasslands. That releases a great deal of carbon dioxide," Searchinger says.

In fact, Searchinger's group's study, published online by Science magazine, shows those actions end up releasing huge amounts of carbon dioxide. The study finds that over a 30-year span, biofuels end up contributing twice as much carbon dioxide to the air as that amount of gasoline would, when you add in the global effects.

Unintended consequences.