Energy Returned on Energy Invested Thread pt 1 (merged) Arch

[pstarr]

I am done over here. You have insulted a good scientist and now me. See you at the Mother Forum.

[Devil]

Don't worry, Pstarr. Lieing is the first stage. When you can't get away with that, you quote the most doubtful "scientist". If that scam is seen through, you make posts that are 1 km long, full of specious arguments, that no one can be bothered to read because they are a waste of time. The final stage is to make ad hominem attacks on anyone who has the temerity to disagree with you. It is all part and parcel of the dishonesty that this kind of subject provokes in both opponent and proponent.

The unfortunate thing is that no one can quote the truth of the matter because there is no single truth. So, paradoxically, anyone who states the truth is a liar.

[EnergySpin]

Don't worry, Pstarr. Lieing is the first stage. When you can't get away with that, you quote the most doubtful "scientist". If that scam is seen through, you make posts that are 1 km long, full of specious arguments, that no one can be bothered to read because they are a waste of time. The final stage is to make ad hominem attacks on anyone who has the temerity to disagree with you. It is all part and parcel of the dishonesty that this kind of subject provokes in both opponent and proponent.

The unfortunate thing is that no one can quote the truth of the matter because there is no single truth. So, paradoxically, anyone who states the truth is a liar.

Devil, I never lied ... my arguments are transparent and no one really is addressing this (not even you). There are good reasons NOT to go down this route, but the energy bduget is not one of them. If you think I lied or I am dishonest, I would appreciate if you used the same data (Pimentel's, not mine) to answer the question. As matters stand I'm done with this thread myself. And I have wasted my time not yours ... you did not even bother to read them.
Cheers
PS Regarding the ad hominem attacks I responded (asymmetrically) I'm afraid to similar challenges.
Edit
------
Examples of why NOT to go down this route, inspite of a net gain energy profit were published in the July issue of Bioscience ( BioScience, Volume 55, Number 7, July 2005, pp. 593-602(10) ) and summarized :
here in the case of the USA and Brazil

A new study of CO2 emissions, cropland area requirements, and other environmental consequences of corn- and sugarcane- ethanol production in the US and Brazil concludes that despite the net energy and CO2 benefits offered by the fuel, using ethanol as a full substitute for gasoline is neither sustainable nor environmentally friendly once the ecological footprint values are factored in.

The researchers also concluded, however, that as part of a diverse energy and fuel portfolio of alternatives to petroleum, “ the ethanol option probably should not be wholly disregarded.”

The paper, “Ethanol as Fuel: Energy, Carbon Dioxide Balances, and Ecological Footprint,” is to be published in the July 2005 issue of BioScience, the journal of the American Institute of Biological Sciences (AIBS).

The researchers, Marcelo E. Dias de Oliveira, Burton E. Vaughan, and Edward J. Rykiel, Jr., use the “ecological footprint” concept to frame the requirements for ethanol production from sugarcane, now widespread in Brazil, and from corn, the main feedstock in the United States.

The ecological footprint is an accounting tool based on two fundamental concepts, sustainability and carrying capacity. It allows the estimation of the resource consumption and waste assimilation requirements of a defined human population or economy sector in terms of corresponding productive land area.

Based on their assumptions and analysis, ethanol carries a positive energy balance (i.e., yielding more energy than directly required to produce it). That conclusion will be somewhat contentious on its own, as the academic debate over ethanol continues to volley back and forth over that precise question. ....
Dias de Oliveira and colleagues then looked at some consequences of moving to greater fuel ethanol use. The results were unfavorable to fuel ethanol in either country. In Brazil, reducing the rate of deforestation seemed likely to be more effective for taking carbon dioxide out of the atmosphere. In the United States, reliance on ethanol to fuel the automobile fleet would require enormous and ultimately unachievable areas of corn agriculture, and the environmental impacts would outweigh its benefits.

(environmental impacts: CO2 emissions (mainly) )
MaxPlank institute in Germany has also looked into the issue (look at page 10) of the following PDF : http://www.european-climate-forum.net/e ... ummary.pdf
which raise the issue of land conflict, potential for over-exploitation and eco-disaster in the 3rd world etc.
IMHO it is important to know why something will (not) work instead of simply and stubbornly stating that it will not work but using the wrong arguments

[pstarr]

Don't worry, Pstarr. Lieing is the first stage. When you can't get away with that, you quote the most doubtful "scientist". If that scam is seen through, you make posts that are 1 km long, full of specious arguments, that no one can be bothered to read because they are a waste of time. The final stage is to make ad hominem attacks on anyone who has the temerity to disagree with you. It is all part and parcel of the dishonesty that this kind of subject provokes in both opponent and proponent.

The unfortunate thing is that no one can quote the truth of the matter because there is no single truth. So, paradoxically, anyone who states the truth is a liar.

I do not believe it is dishonesty. I believe it is a paid agenda. EnergySpin is a friend of JohnDenver EnergySpin on JohnDenver's Anti-Peakoil Web Site. They are professional debunkers. They make a living confusing people for their masters at Archer Daniel Midlands.

[pstarr]

EnergySpin,

Here is Pimentel's data. Please refute it

Table 3. Average Inputs and Energy Inputs Per Hectare Per Year for Switchgrass Production
Input Quantity 10x3 kcal Dollars
Labor 5 hr 20 $65
Machinery 30 kg 555 50
Diesel 100 L 1,000 50
Nitrogen 50 kg 800 28
Seeds 1.6 kg 100 3
Herbicides 3 kg 300 30
Total 10,000 kg yield 2,755 $230
40 million input/ 1:14.4k
kcal yield output ratio

This table 3 shows that the energy content of the switchgrass is 14.4 times the input energy into the product.
******

Table 4. Inputs Per 1000 l of 99.5% Ethanol Produced From
U.S. Switchgrass
Inputs Quantities kcal × 1000 Costs
Switchgrass 2,500 kg 694 $250
Transport, switchgrass 2,500 kg 300 15
Water 125,000 kg 70 20
Stainless steel 3 kg 45 11
Steel 4 kg 46 11
Cement 8 kg 15 11
Grind switchgrass 2,500 kg 100h 8
Sulfuric acid 118 kg 0 83
Steam production 8.1 tons 4,404 36
Electricity 660 kWh 1,703 46
Ethanol conversion to 99.5% 9 kcal/L 9 40
Sewage effluent 20 kg (BOD) 69 6
Total 7,455 $537

This translates to:

Inputs per 1,000 l of ethanol: 7,455,000 kcals.
Outputs per 1000 l of ethanol: 5,130,000 kcals.

Therefore, in Pimentel’s words it “requires 45% more fossil energy to produce 1 l of ethanol using 2.5 kg switchgrass than the energy in a liter of ethanol."

[EnergySpin]

Hello pstarr
I apologise about the comment about the college; I should ask my mother for a refund, for not insisting I learn manners
I do not have any problem with Table 3 (even though there seem to be a confusion about the nature of the switchgrass feedstock produced).
The energy return of the first step is therefore 14.4 (or 19 something if you do not use the emboddied energy). Note that the inputs include many stuff, including machinery hence this process can result in a net energy gain.
This is the reason behind the pelletization process and the use of switchgrass in coal fired plants. Do you agree with this so far?

Lets go to Table 4. First of all note that Pimente underestimates the cost of distilling ethanol out of switchgrass due to an error in Table 4. He (incorrectly) lists the energy content of 2500 tons of switchgrass as 694000 kcals where in fact it is 10million. If you permit me I will correct this (it is wrong to divide only one number, if you change the scale of measurement you have to do it for all numbers).
So Table 4 should be something like:

Table 4. Inputs Per 1000 l of 99.5% Ethanol Produced From
U.S. Switchgrass
Inputs Quantities kcal × 1000 Costs
Switchgrass 2,500 kg 10000 $250
Transport, switchgrass 2,500 kg 300 15
Water 125,000 kg 70 20
Stainless steel 3 kg 45 11
Steel 4 kg 46 11
Cement 8 kg 15 11
Grind switchgrass 2,500 kg 100h 8
Sulfuric acid 118 kg 0 83
Steam production 8.1 tons 4,404 36
Electricity 660 kWh 1,703 46
Ethanol conversion to 99.5% 9 kcal/L 9 40
Sewage effluent 20 kg (BOD) 69 6

Inputs are 10000+300+70+45+46+15+100+4404+1703+9+69 =17197
The actual energy efficiency of this step is therefore 29.8%
The conclusion is that for plants which operate this way, in order to recover 50% of the energy contained in the switchgrass (5100/1000) one has to invest a significant amount of additional energy.
If the plant burns 40% of the lignin component (which is the position of NREL and Arkenol), one has to subtract 4000 kcal from the input, and the energy efficiency step is therefore higher 5100/13197 ca 40%

Note that a statement such as: it takes x amount more energy than the energy contained in gasoline can be made, but the interpretation will be different to different people. For example refining 42 gals (1 barrel) of oil to gasoline results in 19.5 gals of gasoline but requires an extra input of 2-12% of the energy contained in the feedstock.
Technically Pim is not incorrect in stating that refining is an energy looser, but distillation will always be an energy looser (you can see that in the case of gasoline).
The important question is whether growing switchgrass to produce ethanol is a net looser, since one gained energy in the first step, energy that one would not have if farming had not be done. What are the inputs for this process? Everyting in Table 3 + everything else (with the exception of switchgrass) in Table 4. Note than 10 tons (the output of 1 ha) is 4 times the amount of switchgrass so one has to multiple gains and costs by 4 .
Output is therefore 4 x 5100 = 20400 kcals. Inputs are: 2755+ 4 x 7197 (when the lignin part is not burnt) or 2755+ 4 x 3197 (if it is burnt)
EROEI = 20400/(2755+28788) = 0.64 (first case) OR 1.31 (second case)
The way one does the processing can influence the results and Pim did not do the calculations all the way. Had he done the calculations he would have been able to give the holistic EROEI which depends on the way the grass is processed.
IF biofuels are to be energy source (and not carrier) then 4 questions have to answered in succession:
1) Does it have an EROEI > 1 (it does in modern practises)
2) How reliable is it as a process? (more data are needed, I cannot answer that one needs more data than averages)
3) What is the absolute yield of energy (this is 20400*0..3)
4) How does it relate to the demant?
5) Are there any land conflicts?
6) Can we use the resource more effectively?
Going down the checklist one finds that switchgrass-ETOH passes 1 (under the modern refinery processes) but runs into problems of 4 and 5 when the process is scaled up.
A more efficient use of the resource is to pelletize it and burn it in coal fire plants or stoves preferably close to the point of production (the only cost would be transport then).
The wrongful way of doing the calcs blur the important issues which go above and beyond the EROIE I'm afraid. But let's start with accurate calcs to understand why one particular solution is not an effective solution (in spite of the net energy gain) , or that it is a good solution to a different problem (decrease in emissions, or land remediation).

[EnergySpin]

Don't worry, Pstarr. Lieing is the first stage. When you can't get away with that, you quote the most doubtful "scientist". If that scam is seen through, you make posts that are 1 km long, full of specious arguments, that no one can be bothered to read because they are a waste of time. The final stage is to make ad hominem attacks on anyone who has the temerity to disagree with you. It is all part and parcel of the dishonesty that this kind of subject provokes in both opponent and proponent.

The unfortunate thing is that no one can quote the truth of the matter because there is no single truth. So, paradoxically, anyone who states the truth is a liar.

I do not believe it is dishonesty. I believe it is a paid agenda. EnergySpin is a friend of JohnDenver EnergySpin on JohnDenver's Anti-Peakoil Web Site. They are professional debunkers. They make a living confusing people for their masters at Archer Daniel Midlands.

There are many other people contributing to JDs ... is there a law against contributing? I do contribute occasionally to his site using the same alias I use at po.com
Regarding the professional debunking business .. I do not think so, but then again one has to keep in mind that with the exception of the admins and Devil himself , everyone else is essentially anonymous on this corner of the internet

[pstarr]

He (incorrectly) lists the energy content of 2500 tons of switchgrass as 694000 kcals where in fact it is 10million.

The 694000kcal value is not the energy content of 2500 tons of switchgrass. It is the energy cost of the input into the fermenter to grow the switchgrass. And it is not in tons it is in kilos.

Given these two obvious mistakes (kilos not tons and cost not content) I did not even bother to read the rest of your analysis.

[EnergySpin]

He (incorrectly) lists the energy content of 2500 tons of switchgrass as 694000 kcals where in fact it is 10million.

The 694000kcal value is not the energy content of 2500 tons of switchgrass. It is the energy cost of the input into the fermenter to grow the switchgrass. And it is not in tons it is in kilos.

Given these two obvious mistakes (kilos not tons and cost not content) I did not even bother to read the rest of your analysis.

An energy analysis adds outputs of real energies and subtracts real energy costs. If you scale any number you have to scale all of them
Yes it is kgrs ... I'm afraid I did not put the decimal point

[BabyPeanut]

France Enacts Measures to Lower Fuel Costs (link)
13 September 2005

French Prime Minister Dominique de Villepin announced measures Tuesday to help French farmers cope with skyrocketing gasoline prices. Besides cutting fuel taxes, the government aims to reduce overall consumption by focusing on energy alternatives.

...skip...

The French prime minister announced another measure likely to directly help them: increasing the production of biofuels - gasoline and diesel substitutes like ethanol, which are produced from crops.

...snip...

versus

Fuel's gold - Turning corn into ethanol may not be worth it (link)

...skip...

There's just one catch: According to scientists in New York and California, it takes more energy to make ethanol than you get back in fuel savings. More precisely, says David Pimentel of Cornell University, it takes the equivalent of 1.29 gallons of gasoline to produce enough ethanol to replace one gallon of gasoline at the pump. Instead of making the nation more energy self-sufficient, ethanol production actually increases our need for oil and gas imports, Pimentel says.

...snip...

and

UC scientist says ethanol uses more energy than it makes (link)
A lot of fossil fuels go into producing the gas substitute
Elizabeth Svoboda, Special to The Chronicle
Monday, June 27, 2005

...skip...

in a recent issue of the journal Critical Reviews in Plant Sciences, UC Berkeley geoengineering professor Tad Patzek argued that up to six times more energy is used to make ethanol than the finished fuel actually contains.

...snip...

[Nano]

We see the same kind of thing in Holland. My government will force oil companies to add 20% biofuel to gasoline and sells that as a method to solve peak oil.

What does this all mean?

For certain the government knows about the EROEI problems associated with biofuels. Therefore, their so-called solutions are cynical attempts to stifle calls for drastic societal reform and serious preparation for peak oil.

In other words: these maniacs are looking only toward their personal monthly pay-checks and are keeping an eye on the latest opportunity to jump-ship and leave humanity to destroy itself while they are 'gone fishing'

Bastards. It's almost time for bloody revolution. Oh well. Shit happens.

[EnergySpin]

BabyPeanut ... there was a decent sized thread on how to lie about the EROEI and how Pimentel and DOE/NREL are arguing about different things.
In fact Pimentel's numbers when added properly do suggest a net gain even for corn-etoh (an energy hog)
In addition, there were at least 2-3 papers by European researchers which did show that the net gain is positive (and they used quantitative life cycle models) and not back of envelope calculations. European researchers by many different countries have discussed the issue of scale; Europe could not meet their liquid fuel energy needs from current farm land available in Europe. This is why the biofuel research there is quite diverse, ethanol from different plants, methanol from wood and biodiesel. Taken together all these may meet a sizeable portion of European liquid energy needs (close to 30-40%) without land conflicts. By the way this is the same figure that the R.E.A.P program in Canada calculated on the basis of land use, perennial grasses as feedstock etc that is achievable in NA without compromising food production.
The only real question is whether turning biomass in liquid fuels is the best resource management strategy and the answer is probably no. There are positive energy gains in growing and pelletizing biomass (even Pimentel says that) which can then be used to generate electricity either in conventional or cogeneration facilities. 10% of all coal burned for electricity can be replaced today with signifcant benefits from an emission standpoint. This would be a much better use of biomass compared to converting it to liquid biofuels (even though this still has a small but measurable energy gain).
The French PM is a f****** idiot (as many French people know) but the base for his statements is research that his government and the EU have both funded.

[BabyPeanut]

Tad Patzek's is more recent than Pimentel's
(link)

But in a recent issue of the journal Critical Reviews in Plant Sciences, UC Berkeley geoengineering professor Tad Patzek argued that up to six times more energy is used to make ethanol than the finished fuel actually contains.

The fossil energy expended during production alone, he concluded, easily outweighs the consumable energy in the end product. As a result, Patzek believes that those who think using the "green" fuel will reduce fossil fuel consumption are deluding themselves -- and the federal government's practice of subsidizing ethanol by offering tax exemptions to oil refiners who buy it is a waste of money.

"People tend to think of ethanol and see an endless cycle: corn is used to produce ethanol, ethanol is burned and gives off carbon dioxide, and corn uses the carbon dioxide as it grows," he said. "But that isn't the case. Fossil fuel actually drives the whole cycle."

Patzek's investigation into the energy dynamics of ethanol production began two years ago, when he had the students in his Berkeley freshman seminar calculate the fuel's energy balance as a class exercise.

Once the class took into account little-considered inputs like fossil fuels and other energy sources used to extrude alcohol from corn, produce fertilizers and insecticides, transport crops and dispose of wastewater, they determined that ethanol contains 65 percent less usable energy than is consumed in the process of making it.

Surprised at the results, Patzek began an exhaustive analysis of his own -- one that painted an even bleaker picture of the ethanol industry's long- term sustainability.

"Taking grain apart, fermenting it, distilling it and extruding it uses a lot of fossil energy," he said. "We are grasping at the solution that is by far the least efficient."

Patzek's report also highlights the potential environmental hazards of ethanol production.

"When you dump nitrogen fertilizer on corn fields, it runs away as surface water, into the Mississippi River and Gulf of Mexico," he said.

The excess nitrogen introduced into the water causes out-of-control algae growth, creating an oxygen-poor "dead zone" where other marine plants and animals cannot survive. And while ethanol produces fewer carbon monoxide emissions than regular gasoline, some researchers have found that ethanol releases high levels of nitrogen oxide, one of the principal ingredients of smog, when burned.

...skip...

"So what if we have to spend 2 BTUs for each BTU of alcohol fuel produced?" reads an editorial in the Offgrid Online energy newsletter. "Since we are after a portable fuel, we might be willing to spend more energy to get it."

[MacG]

A simple challenge to ALL biofuels:

When I see a biofuel operation running without fossile inputs, then I'll belive in the thing. It should be priority no:1 for any biofuels prophet to get a closed system running for real.

[BabyPeanut]

A simple challenge to ALL biofuels:

When I see a biofuel operation running without fossile inputs, then I'll belive in the thing. It should be priority no:1 for any biofuels prophet to get a closed system running for real.

When I see a factory that makes wind turbines and/or solar panels running 100% off of power from wind turbines and/or solar panels then I will believe.

[EnergySpin]

Tad Patzek's is more recent than Pimentel's
(link)

But in a recent issue of the journal Critical Reviews in Plant Sciences, UC Berkeley geoengineering professor Tad Patzek argued that up to six times more energy is used to make ethanol than the finished fuel actually contains.

The fossil energy expended during production alone, he concluded, easily outweighs the consumable energy in the end product. As a result, Patzek believes that those who think using the "green" fuel will reduce fossil fuel consumption are deluding themselves -- and the federal government's practice of subsidizing ethanol by offering tax exemptions to oil refiners who buy it is a waste of money.

"People tend to think of ethanol and see an endless cycle: corn is used to produce ethanol, ethanol is burned and gives off carbon dioxide, and corn uses the carbon dioxide as it grows," he said. "But that isn't the case. Fossil fuel actually drives the whole cycle."

Patzek's investigation into the energy dynamics of ethanol production began two years ago, when he had the students in his Berkeley freshman seminar calculate the fuel's energy balance as a class exercise.

Once the class took into account little-considered inputs like fossil fuels and other energy sources used to extrude alcohol from corn, produce fertilizers and insecticides, transport crops and dispose of wastewater, they determined that ethanol contains 65 percent less usable energy than is consumed in the process of making it.

Surprised at the results, Patzek began an exhaustive analysis of his own -- one that painted an even bleaker picture of the ethanol industry's long- term sustainability.

What is surprising is the fact that Patzek and Pimentel and NREL and the Europeans are all right, but they are not talking about the same thing.
Biofuels and even gasoline are processes that consist of two steps
Step 1: You grow something (corn,switchgrass, whatever) or you drill for oil
Step 2: You convert it to liquid fuel

In Step 1 you gain a lot of energy .... even Pimentel admits that. For switchgrass the number is 14.4 times higher than the energy investment
(EROEI of 14.4), for the Saudi oil is 20 or 30.

In Step 2: you convert it to liquid fuel. You loose energy at this point no matter which feedstock you process:
a) the conversion process will never convert 100% of all the energy found in switchgrass or oil
b) you need an additional input of energy (i.e. electricity, transportation costs etc) to run the refinery
The National Resources study that everyone has been quoting on the web IS NOT A STATEMENT about the EROIE of Step 1 AND Step 2, but only of step 2.
NREL's corn/switchgrasss/biodiesel studies are about the EROIE of Step 1 AND Step 2.
People are comparing apples to oranges .... I did go over Pimentel and Patzek study---> http://peakoil.com/post179283.html#179283
for my final post on this.
Let me give you food for thought:
One barrel of oil (42 gals) yields 19.5 gals of gasoline and an additional input of 10% of additional energy is required to power the refinery, transfer the oil to the refinery etc.

Based on these numbers the following statement is true: " Gasoline contains 65 percent less usable energy than is consumed in the process of making it"
Why? Because to refine oil to gasoline I had to input the equivalent of 1.1 barrels of oil (1 as oil, 0.1 as electricity etc) and got back only 40% of the energy contained in oil as gasoline (I took into account the different energy contents of gasoline and oil to derive this number). EROIE = 0.4/1.12 = 35%!

But I am not answering the question you really wanted to ask: What is the EROEI of oil drilling+oil refining? Pim and Patzek never do the calculation that is relevant; everyone else does, that's why they conclude that the EROEI is positive. There are other factors that kill ethanol as our saviour! (it is not, it will be a component in an energy basket mix) and I went through them in that lengthy and flammy thread.

[EnergySpin]

A simple challenge to ALL biofuels:

When I see a biofuel operation running without fossile inputs, then I'll belive in the thing. It should be priority no:1 for any biofuels prophet to get a closed system running for real.

Have you seen a refinery or an oil rig that runs on gasoline?
No ... the only really closed system is actually coal mining. They burn coal in place to generate electricity to power the mining machine monsters.
I would suggest downloading Wang's LCA analysis of liquid fuels or read oilanalytics excellent energy quality analysis on the EROEI of oil.
Pimentel is arguing that everyone is using tight system boundaries, yet he never uses a LCA only back of envelope calculations.
NREL provides such a model for everyone to play with:
http://www.transportation.anl.gov/softw ... index.html

When one frames these questions in energy flow diagrams ... then you will see some pretty surprising results. IMHO biofuel research needs:
- metrics
- standards
- LCA diagrams
- queing models
All of those are used by researchers at various Renewable Energy Labs ... but the answer is not in the EROIE ... there are other reasons not to go down this route but this is not becuase biofuels are net energy loosers
The best summary of the research issues involved, is a small paper by a professor in New Zealand (no math, a pleasure to read) cause he puts everything in perspective and gives a checklist of things to look for
http://www.world-council-for-renewable- ... E-SIMS.pdf
Cheers

[Z]

Aside from the EROEI, as I understand, corn production is very water intensive. We had a severe drought this year, and I don't know how much of the crops has been lost, since irrigation was restricted in more than 60% of the territory.

I wonder if any massive increase in the quantity of corn grown is feasible at all, at least in France, especially in regard of climate change.

What are the requirements in water/environmental conditions for alternative crops ( switchgrass ? ) ?

Any thoughts ?

[EnergySpin]

Aside from the EROEI, as I understand, corn production is very water intensive. We had a severe drought this year, and I don't know how much of the crops has been lost, since irrigation was restricted in more than 60% of the territory.

I wonder if any massive increase in the quantity of corn grown is feasible at all, at least in France, especially in regard of climate change.

What are the requirements in water/environmental conditions for alternative crops ( switchgrass ? ) ?

Any thoughts ?

http://www.switchgrass.nl (a european study about switchgrass)
Water is a prime concern Z..... by depleting an aquifer one is doing no good I'm afraid
And other issues as well. Focusing on the EROIE (which is positive I'm afraid), leaves all other issues unaddressed i.e. the fact that the way we go we will end up burning Africa, Amazonia for no good reason.
However, to discount biofuels or renewables or nuclear (examples of positve energy investments) is stupid. They will play a role in the future (I have high hopes for wind+nuclear !!!!) if we are to avoid runaway GW.
Hope you did not mind my calling your PM a fucking idiot?

[Leanan]

IMO, the only biofuel is makes sense to farm is firewood. Once the initial planting is done, it doesn't take a lot of energy to maintain. You harvest branches from the trees, not the whole tree, so you don't have to replant very often, if ever.

The problem with algae, switchgrass, and the like is that they require agribusiness to grow them in significant quantities. Success in the lab or on a small test plot is not the same as success on the acres and acres we will need to make a dent in our oil use.

Here in the northeast, it's easy to grow corn. Toss a few seeds in the backyard, and it grows great, with little care.

It's nearly impossible to grow corn without spraying in, say, rural Kansas. You're surrounded by corn fields. Which means the land has been turned into a heaven on earth for corn pests of all types. Your back yard corn plants will be eaten alive as soon as they poke their heads up.

That's the problem we face with growing any crop in large quantities. They grow fine on their own in the wild, but not in the quantities we require. And once we start growing them in the quantities we require, we start needing herbicides, pesticides, fertilizer, etc.

I do think biofuels have a role. Recyling waste that would otherwise clog our landfills, for example. Like that turkey parts plant. But there's a limit to how much that sort of thing can be scaled up. Plus, I have a feeling we'll be using a lot of what is now agricultural waste as fertilizer in the future.