Ethanol Deception - Is It Really Better Than Gasoline?

[Ivan Seeking]

As I quoted earlier, according to A.E. Farrell: "Our best point estimate for average performance today is that corn ethanol reduces petroleum use by about 95% on an energetic basis...". Therefore, in order to compute "net yields" you need to be using 0.95 instead of 0.3; and then your number above for net yields would be "...Corn = 380 gallons per acre-year".

This has nothing to do with it. We measure the yield and look at how much energy it took to produce that yield. The multiplier is ~0.3 for net yield...and based on the technology in use, that is a best case.

 

[Aether]

This has nothing to do with it. We measure the yield and look at how much energy it took to produce that yield. The multiplier is ~0.3 for net yield...and based on the technology in use, that is a best case.

The multiplier is ~0.3 for net energy, but it is 0.95 for farm land. Ethanol plants use coal and natural gas as energy inputs which accounts for the difference. If these plants had to use all ethanol or petroleum as their only energy inputs then the number for farm land would be ~0.3; but they do not have to do that, nor do they choose to do that in practice.

 

[Ivan Seeking]

What about soybeans and other biodiesel crops? Also, what is figured in for inputs to the crop? On a corn/soybean rotation it is common to not use fertilizer at all for the soybeans. Plant food is derived from the residue of the previous years crop as well as some of the fertilizer applied for the corn crop. I guarantee you that soybeans on the same ground year after year will require some kind of fertilizer. I know next to nothing about algae but I have a very hard time believing that all it requires is air and sunlight. There must be other input to net the amount of biodiesel we are talking about.

Some crops are much better than others, and the amount of fertilizer needed is a critical part of the energy calculation no matter what crop we use. I don't know the specifics of soybeans but it is one of the best options after algae. I'm sure that plenty of information is found with a search as soybean is a major crop used today for biodiesel.

Nitrogen and other nutrients are needed for the algae. This was all considered in the aquatic species program and later research.

One nice thing about algae is that given the proper selection of algae strains, it can survive and even thrive in highly contaminated water. This is why it can be used to clean-up industrial, ag, and municipal waste. What is considered pollution can grow algae at tremendously high rates.

Another part of what makes algae so competitive is the percent yield as a function of oil by weight. There is one strain that has been measured as having as much as 86% oil by weight. Typical yields range between 30 and 50% oil by weight [oil weight compared to weight of dry algae before processing]. And it isn't that hard to understand when you think about it. Algae is a very simply organism that only does a few things. It is also very small - often in the range of about 5 to 10 microns in size - so it is very efficient in that it occupies 100% of the light incident area, and almost all of this is going towards fuel production rather than growing stalks, leaves, etc.

 

[Ivan Seeking]

The multiplier is ~0.3 for net energy, but it is 0.95 for farm land. Ethanol plants use coal and natural gas as energy inputs which accounts for the difference. If these plants had to use all ethanol or petroleum as their only energy inputs then the number for farm land would be ~0.3; but they do not have to do that, nor do they choose to do that in practice.

This is not what the multiplier means. It is a measure of total efficiency. What you are talking about is using other energy to make ethanol, and this is not a viable option as we don't have the power needed to make it. In effect, what you are saying is that we should convert to coal power. And either way, we still couldn't possibly grow enough corn.

In the case of an energy carrier, hydrogen is more efficient as it returns about 50% of the energy used to make it, not 30%. And we don't need corn, just water. Also, hydrogen can be burned in traditional engines.

 

[Aether]

This is not what the multiplier means. It is a measure of total efficiency.

You are trying to use this multiplier to support your claim that farm land yields only 120 gallons of ethanol per acre-year instead of 380. This is clearly wrong.

What you are talking about is using other energy to make ethanol, and this is not a viable option as we don't have the power needed to make it. In effect, what you are saying is that we should convert to coal power.

No, what I am talking about at the moment is how many acre-years of farm land it takes to make 380 gallons of ethanol.

In the case of an energy carrier, hydrogen is more efficient as it returns about 50% of the energy used to make it, not 30%. And we don't need corn, just water.

Maybe so, but that doesn't have anything to do with how many acre-years of farm land it takes to make 380 gallons of ethanol.

Incidentally, if ethanol has 30% net energy, then that means that it returns 130% of the energy used to make it; not 30%.

 

[Ivan Seeking]

If we use coal power to make ethanol, yes, it would take less land. Of course we still couldn't grow enough corn. You keep ignoring this point.

Where are we going to get the power? We don't have it, so we would have to either build a tremendous number of coal plants to produce ethanol, or use ethanol energy produced on-site to make the fuel. Either way we need to get the energy from somewhere.

When we talk about net energy returns, what we mean is how much of the available energy do we get to use. This is 30%. This is how we measure the net energy gain. You can play games all day, but the energy has to come from somewhere, and ethanol can't provide the energy, so ethanol is not an energy solution, which was the point of this thread.

Oh yes, your point about hydrogen is valid. I was using two different ways to compare. With ethanol we put in 66 BTUs and get 100, so we see a 50% gain in this sense. With hydrogen we put in 66 and get back 33 [or so].

 

[Aether]

If we use coal power to make ethanol, yes, it would take less land.

Well, this is how we make ethanol today; using coal and natural gas.

Of course we still couldn't grow enough corn. You keep ignoring this point.

Maybe so, but this is a different issue. You don't mind if we discuss (and resolve) one issue at a time do you?

Where are we going to get the power? We don't have it, so we would have to either build a tremendous number of coal plants to produce ethanol, or use ethanol energy produced on-site to make the fuel. Either way we need to get the energy from somewhere.

We currently get the energy from domestic coal and natural gas; future plans are to use cellulosic ethanol where the energy comes entirely from lignin which is a part of the plants themselves.

When we talk about net energy returns, what we mean is how much of the available energy do we get to use. This is 30%. This is how we measure the net energy gain.

Wrong. If you look at the EBAMM spreadsheet you will see the detailed data from six separate published studies on the subject of the net energy of ethanol production. Here is a summary; output energy includes "coproduct credits":

Patzek: 27 MJ/L energy input vs. 25 MJ/L energy output = 93% return.
Pimentel: 26 MJ/L energy input vs. 23 MJ/L energy output = 88% return.
Shapouri: 21 MJ/L energy input vs. 29 MJ/L energy output = 138% return.
Graboski: 22 MJ/L energy input vs. 25 MJ/L energy output = 114% return.
de Oliviera: 20 MJ/L energy input vs. 25 MJ/L energy output = 125% return.
Wang: 19 MJ/L energy input vs. 25.2 MJ/L energy output = 133% return.

 

[Ivan Seeking]

Currently we have 600 coal plants producing a total of about 22.9 quads of energy annually. All petroleum used has about 38.8 quads of energy with a chain efficiency of about 80%. So we need about 31 quads of energy to replace petro, or 23 quads to make enough ethanol [with a 50% gain based on input power]. So, in order to produce enough ethanol using coal power, we would need about another 600 additional coal plants.

Late edits: I was assuming that we still need to allow for efficiencies already accounted for.

 

[Ivan Seeking]

Well, this is how we make ethanol today; using coal and natural gas.Maybe so, but this is a different issue. You don't mind if we discuss (and resolve) one issue at a time do you? We currently get the energy from domestic coal and natural gas; future plans are to use cellulosic ethanol where the energy comes entirely from lignin which is a part of the plants themselves.

Future options don't count. When they are viable, then they become part of the discussion.

Wrong. If you look at the EBAMM spreadsheet you will see the detailed data from six separate published studies on the subject of the net energy of ethanol production. Here is a summary; output energy includes "coproduct credits":

Patzek: 27 MJ/L energy input vs. 25 MJ/L energy output = 93% return.
Pimentel: 26 MJ/L energy input vs. 23 MJ/L energy output = 88% return.
Shapouri: 21 MJ/L energy input vs. 29 MJ/L energy output = 138% return.
Graboski: 22 MJ/L energy input vs. 25 MJ/L energy output = 114% return.
de Oliviera: 20 MJ/L energy input vs. 25 MJ/L energy output = 125% return.
Wang: 19 MJ/L energy input vs. 25.2 MJ/L energy output = 133% return.

I will have to take some time later to look at what you have, but coproducts don't count unless we can show that first, we can use the byproducts, and next, that we would be saving energy already used today. When one considers the amount of production involved, it is extremely unlikely that we could use most of the byproducts [as a signficant percent of the total yield]. The example of glycerin from biodiesel given earlier is a perfect example. Even now, with only a trickle of biodiesel produced as a percent of total demand, the glycerin market is flooded and the price has dropped. When considering byproducts, we have to first consider the demand for that product, and then the energy used to produce that product today, otherwise the projections are meaningless and the coproduct may even end up as a liability - you will be paying to get rid of it as garbage.

The 0.3 multiplier is correct as an honest measure of the gain based on yield. You are talking about using power from other sources that don't exist.

 

[Aether]

Estimates and three decades of testing indicates that by using algae, we can produce as much as a net 10,000 gallons of biodiesel per acre-year - say 7000 if we stay conservative and allow for a 30% processing demand. See the aquatic species program [in addition to plenty of more recent links found with a simple search] which predicted that algae could be competitive when diesel was at about $2 a gallon, or twice 1996 levels. [see part ii, page 4]
http://www1.eere.energy.gov/biomass/pdfs/biodiesel_from_algae.pdf

Not that we would want to, but a simple estimate suggests that we could replace all sources of energy - petro, coal, NG, hydro, nuclear, wind, solar - with about 400 X 400 miles of land and or water. In the process, algae can be grown while cleaning up CO2 or other industrial, agricultural, or municipal emissions or waste.

The report that you cited was generated in 1998 upon the close-out of the Aquatic Species Program, and here is what this agency has to say about biodiesel today:

Note: The Department of Energy's Office of Biomass Program has refocused its research and development portfolio and the technology on this page is no longer a research priority.

http://www1.eere.energy.gov/biomass/renewable_diesel.html

Currently we have 600 coal plants producing a total of about 22.9 quads of energy annually. All petroleum used has about 38.8 quads of energy with a chain efficiency of about 80%. So we need about 31 quads of energy to replace petro, or 23 quads to make enough ethanol [with a 50% gain based on input power]. So, in order to produce enough ethanol using coal power, we would need about another 600 additional coal plants.

Biodiesel production seems to be dependent on CO2 from coal plants, and therefore it may not be practical on the scale that you envision.

The main focus of the program, know as the Aquatic Species Program (or ASP) was the production of biodiesel from high lipid-content algae grown in ponds, utilizing waste CO2 from coal fired power plants...Algal biodiesel could easily supply several “quads” of biodiesel—substantially more than existing oilseed crops could provide. Microalgae systems use far less water than traditional oilseed crops. Land is hardly a limitation. Two hundred thousand hectares (less than 0.1% of climatically suitable land areas in the U.S.) could produce one quad of fuel.

Future options don't count. When they are viable, then they become part of the discussion.

...the technology faces many R&D hurdles before it can be practicable...

 

[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.