biofuel -
a fossil fuel replacement

a briefing document

site map

On housing and making living systems ecological

Tectonics: tectonic plates - floating on the surface of a cauldron

introduction
yet more bad science from the pseudo-greens
useful, but unreliable, summary on oil from algae
algae to oil due to start operation
biofuels - present reality
cellulosic biofuels

biofuels update - important new survey of biofuel [press release]
on growing interest in cellulosic and other biofuels
switch grass [panicum virgatum] - cellulosic bio-fuel
David Pimentel on the limitations of cellulosic biofuels
the viability of ethanol and cellulosic ethanol

what the ipcc did not say - bush, as the crazy corporate socialist
end notes

introduction

Biofuels are not a single technology. Present biofuels are oil and starch derivatives. The great white hope of biofuels, which appears to growing ever closer, is cellulosic biofuels.

Present biofuels are‘dubious’ and subject to much controversy. With cellulosic technology, that is likely to change to mainstream. With cellulosic technology, the whole of the plant matter comes open for exploitation.

Bio-fuels will compete with food and for farmland, while the increasing growth of plants for bio-fuels will make greater demands on water resources for irrigation.

biofuel

Current biofuels are heavily subsidised and often EROEI-uneconomic. Much of the process is fossil fuel-driven, such as farm machinery, fertiliser, herbicides, insecticides and refining. Agriculture is heavily dependant on water supply and sunlight. Biofuels are no easy option.

Note: it is probable that growing knowledge in GM [genetic modification] methods of modifying plants will alter future balances.

yet more bad science from the pseudo-greens

“The rush to make energy from vegetable oils is being driven in part by European Union laws requiring conventional fuels to be blended with biofuels, and by subsidies equivalent to 20 pence a litre. Last week, the British government announced a target for biofuels to make up 5 per cent of transport fuels by 2010. The aim is to help meet Kyoto protocol targets for reducing greenhouse-gas emissions.

“Rising demand for green energy has led to a surge in the international price of palm oil, with potentially damaging consequences. "The expansion of palm oil production is one of the leading causes of rainforest destruction in south-east Asia. It is one of the most environmentally damaging commodities on the planet," says Simon Counsell, director of the UK-based Rainforest Foundation [...].”
—
“ The main alternative to palm oil is soybean oil. But soya is the largest single cause of rainforest destruction in the Brazilian Amazon.”

Note, sugar cane is also an importment biofuel crop, especially in Brazil (quoted up to 8:1 EROEI). See also dodgy report on sugar cane crop insect attack

useful, but unreliable, summary on oil from algae

The item is rather casual about the problems of salination and inputs. Obviously, it will require a lot of power and access to feedstocks to run the system, but it is an very interesting approach.

Advised reading, with caution.

This link is to a more detailed and careful survey, linked from the above document. However, it is a 328-page .pdf file. Because I am still attempting to read through the .pdf, this abelard.org biofuel item should be treated as ‘in development’. For instance, read from p. 255 and you will receive a much less rosy picture than from the short item.

Algae can grow in saline water, thus not displacing useful farm land.

“Microalgae are the most primitive form of plants. While the mechanism of photosynthesis in microalgae is similar to that of higher plants, they are generally more efficient converters of solar energy because of their simple cellular structure. In addition, because the cells grow in aqueous suspension, they have more efficient access to water, CO2, and other nutrients. For these reasons, microalgae are capable of producing 30 times the amount oil per unit area of land, compared to terrestrial oilseed crops.” [.pdf page 9]

algae to oil due to start operation

Naturally growing algae

“The Rio Hondo, Texas algae farm will commence operations on April 1, 2008 as PetroSun's initial commercial algae-to-biofuels facility. The current algae farm consists of 1,100 acres of saltwater ponds that the Company projects will produce a minimum of 4.4 million gallons of algal oil and 110 million pounds of biomass on an annual basis. The Company has dedicated 20 acres of ponds for a proposed algae derived JP8 jet fuel research and development program.”
—
“ "Our business model has been focused on proving the commercial feasibility of the firms' algae-to-biofuels technology during the past eighteen months," [...] ”

The company site.

advertising disclaimer

biofuels - present reality

Abstract of Ethanol Production Using Corn, Switchgrass, and Wood; Biodiesel Production Using Soybean and Sunflower by David Pimentel and Tad W. Patzek

“Energy outputs from ethanol produced using corn, switchgrass, and wood biomass were each less than the respective fossil energy inputs. The same was true for producing biodiesel using soybeans and sunflower, however, the energy cost for producing soybean biodiesel was only slightly negative compared with ethanol production. Findings in terms of energy outputs compared with the energy inputs were:

• Ethanol production using corn grain required 29% more fossil energy than the ethanol fuel produced.
• Ethanol production using switchgrass required 50% more fossil energy than the ethanol fuel produced.
• Ethanol production using wood biomass required 57% more fossil energy than the ethanol fuel produced.
• Biodiesel production using soybean required 27% more fossil energy than the biodiesel fuel produced. (Note, the energy yield from soy oil per hectare is far lower than the ethanol yield from corn; but see where 3.5:1 gain is claimed.)
• Biodiesel production using sunflower required 118% more fossil energy than the biodiesel fuel produced.”

Biofuel yields in terms of volume and energy per hectare for
selected ethanol and biodiesel feedstock Credit: Royal Society

This chart is for various feedstocks, showing the basic gross output; that is without energy costs for production.
A litre of ethanol provides about sixty-five percent the energy of a litre of petrol/gasoline.
A litre of biodiesel provides about eighty-five percent the energy of a litre of regular diesel.

As you can see from the chart above, essentially, bioethanol is produced from starches and sugars, while biodiesel is made from plant oil sources.

growing biofuel production

“The world produced 52 billion litres of ethanol in 2007, mostly in the United States and Brazil, three times the level in 2000, according to U.N. data. It produced 10 billion litres of biodiesel, up 11-fold since 2000.”

cellulosic biofuels

biofuels update - important new survey of biofuel [press release]

“[...] it is already clear that large-scale use of ethanol for fuel will almost certainly require cellulosic technology”, that is present methods are not energetically viable. They will have to be supplemented with methods, presently under development, designed also to convert the cellulose elements of the plant to produce ethanol.

“Once these changes were made in the six studies, each yielded the same conclusion about energy: Producing ethanol from corn uses much less petroleum than producing gasoline. However, the UC Berkeley researchers point out that there is still great uncertainty about greenhouse gas emissions and that other environmental effects like soil erosion are not yet quantified.”
—
“ The goal of the UC Berkeley analysis was to understand how six studies of fuel ethanol could come to such different conclusions about the overall energy balance in its production and use. Farrell, Kammen and their UC Berkeley colleagues dissected each study and recreated its analysis in a spreadsheet where they could be compared side-by-side. The team said it found numerous "errors, inconsistencies and omissions" among the studies, such as not considering the value of co-products of ethanol production - dried distillers grains, corn gluten feed and corn oil - that boost the net energy gain from ethanol production. Other studies overestimated the energy used by farm machinery.

“On the other side, some studies ignored the use of crushed limestone on corn fields, which can be a significant energy input because of the need to pulverize the rock. Farrell noted that some numbers needed for the analysis, such as the amount of limestone applied, are just not known reliably. On the other hand, some of the studies used outdated data when more recent numbers were available, making ethanol look worse.”

The full paper.
The supplementary data for the paper.

switch grass [panicum virgatum] - cellulosic bio-fuel

“Abstract
Perennial herbaceous plants such as switchgrass (Panicum virgatum L.) are being evaluated as cellulosic bioenergy crops. Two major concerns have been the net energy efficiency and economic feasibility of switchgrass and similar crops. All previous energy analyses have been based on data from research plots (<5 m2) and estimated inputs. We managed switchgrass as a biomass energy crop in field trials of 3–9 ha (1 ha = 10,000 m2) on marginal cropland on 10 farms across a wide precipitation and temperature gradient in the midcontinental U.S. to determine net energy and economic costs based on known farm inputs and harvested yields. In this report, we summarize the agricultural energy input costs, biomass yield, estimated ethanol output, greenhouse gas emissions, and net energy results. Annual biomass yields of established fields averaged 5.2 -11.1 Mg·ha–1 with a resulting average estimated net energy yield (NEY) of 60 GJ·ha–1·y–1. Switchgrass produced 540% more renewable than nonrenewable energy consumed. Switchgrass monocultures managed for high yield produced 93% more biomass yield and an equivalent estimated NEY than previous estimates from human-made prairies that received low agricultural inputs. Estimated average greenhouse gas (GHG) emissions from cellulosic ethanol derived from switchgrass were 94% lower than estimated GHG from gasoline. This is a baseline study that represents the genetic material and agronomic technology available for switchgrass production in 2000 and 2001, when the fields were planted. Improved genetics and agronomics may further enhance energy sustainability and biofuel yield of switchgrass.”

Full article from pnas.org.

“From the biomass of grasses [panicum virgatum] harvested, they calculated that ethanol derived from them should yield 5.4 times as much energy as all these inputs combined.”

Switchgrass is related to millet, the only version of panicum that is fairly common in Europe. Several panicum cultivars are sold in the USA as decorative garden plants.

credit: intheburg

david pimentel’s comments on pnas.org article cited above -
on the limitations of cellulosic biofuels

David Pimentel is a world authority on this stuff:

1. They use a third-hand reference source to claim that they can produce a net of 0.38 liter of ethanol from 1 kg of switchgrass . No one in the world has been able to produce net ethanol energy from cellulosic biomass to date, except in paper models. This is the reason that there is no commercial plant in the world converting cellulosic biomass into ethanol. There are billions of dollars invested today in research to achieve this conversion and I support all this research.
   
   
2. The authors never report that it takes from 2 to 5 times more cellulosic biomass than corn grain to produce 1 litre of ethanol. Cellulosic biomass contains significantly less starches and sugars than corn grain. One does not have to be a expert to appreciate this fact - all one has to do is hold a handful of switchgrass straw and a handful of corn to appreciate this fact.
   —
   
5. The authors suggest that cellulosic ethanol sources can provide 30% of U.S. current petroleum consumption. The report advocates using 1.3 billion tons of cellulosic biomass. They are suggesting using nearly 66% of all forests, all agricultural crops, and all grasses each year to produce this cellulosic ethanol. Literally the U.S. would be stripped of its vegetation. The result would be that soil erosion would intensify, water runoff would increase, and global warming would increase.
   
   
6. I am truly concerned when people publish some unscientific opinions such as these because they mislead the people and politicians. At present there is no easy solution and we in science need to be investigating all potential renewable energy technologies and cease claims that ethanol from cellulosic biomass is the solution to all U.S. energy problems. A truly thorough examination of biomass and its environmental relationship to water, land, and solar energy is needed. [David Pimentel, quoted from eclipse-chat.blogspot.com]

related material
table on required land use for alternative replacement energy production in USA

the viability of ethanol and cellulosic ethanol

“Cellulosic ethanol currently costs about double the price as making the fuel from corn, the main US ethanol feedstock. Venture capitalists and companies that are making small amounts of cellulosic ethanol say once the industry gets underway, biological advances in the fungi and other organisms used to break down woody plant bits into fuel will make the process cheaper.

“Switchgrass plants sequester carbon dioxide in the ground because they have extensive root systems that remain buried after the crop is harvested, Vogel said. Steep greenhouse gas emissions reductions, of about 94 percent compared to gasoline, are contingent on burning switchgrass waste to fire bio-refineries. Unlike waste left over from corn after it is made into ethanol, switchgrass waste cannot be made into the animal feed distillers' grain.”
—
“ Several recent studies have suggested corn ethanol yields about 1.25 to 1.50 times more energy than it takes to grow and process the grain into fuel.” [Quoted from planetark.org]

Switchgrass plants can be managed as perennials, sequestering further carbon in their systems.

“About 12 million hectares, or around 1% of the world's fields, are already devoted to growing biofuels, and this figure is set to grow.

“But a host of new studies question the logic behind expanding biofuel production. For a start, they can use up land normally used to grow the crops for food production and increase demands on water supplies. Worse, it is debatable how much of a reduction in carbon dioxide emissions a switch to biofuels would produce.” [Quoted from newscientist.com]

on growing interest in cellulosic and other biofuels

This item is written by a fellow who is promoting biofuels and who is clearly influencing the US government. I do not trust his detachment.

“ [...] It takes about 30% more ethanol than gasoline to drive a mile, and the stuff is more corrosive, but building a car that's E85-ready adds only about $200 to the cost. Ethanol has already transformed one major economy: In Brazil nearly three-quarters of new cars can burn either ethanol or gasoline, whichever happens to be cheaper at the pump, and the nation has weaned itself off imported oil.

That is, a free market approach.

“The next five years could see ethanol go from a mere sliver of the fuel pie to a major energy solution in a world where the cost of relying on a finite supply of oil is way too high. As that happens, says Vinod Khosla, a Silicon Valley venture capitalist who has become one of the nation's most influential ethanol advocates, "I'm absolutely convinced that without putting any more land under agriculture and without changing our food production, we can introduce enough ethanol in the U.S. to replace the majority of our petroleum use in cars and light trucks." ”
—
“ Ethanol's rise has had far-reaching effects on the economy. Not only does Brazil no longer have to import oil but an estimated $69 billion that would have gone to the Middle East or elsewhere has stayed in the country and is revitalizing once-depressed rural areas [...] ”
—
“ [...] Already ethanol gobbles up 14% of the country's [the USA] corn production. Converting a bigger share into fuel would pinch the world's food supply--a favorite objection of skeptics. Critics also contend that producing fuel from crops consumes more energy than it yields. On this topic of endless Internet bickering, the Energy Department recently reported, "In terms of key energy and environmental benefits, cornstarch ethanol comes out clearly ahead of petroleum-based fuels, and tomorrow's cellulosic-based ethanol would do even better."

“Because cellulosic ethanol comes from cornstalks, grasses, tree bark-fibrous stuff that humans can't digest--it doesn't threaten the food supply at all. Cellulose is the carbohydrate that makes up the walls of plant cells. Researchers have figured out how to unlock the energy in such biomass by devising enzymes that convert cellulose into simpler sugars. Cellulose is abundant; ethanol from it is clean and can power an engine as effectively as gasoline. Plus, you don't have to reinvent cars. Ratcheting up production of cellulosic ethanol, however, is a gnarly engineering problem”
—
“ [...] Because sugar cane generates far more ethanol per acre than corn, Brazil can produce ethanol more cheaply than the U.S. Not only would importing more of it broaden access to ethanol for U.S. buyers, but it would also make it cheaper for the ultimate consumers--us. That in turn would spur demand at the pump and encourage service station owners to offer ethanol more widely [...] ”

Although until recently the energy input required to create biofuels was not far off what was given in return, the situation is changing as technology rushes forward.

1. At the moment, biofuel technology consists of squeezing oil out of oil-bearing plants and fermenting starches. That is, in my view, not energetically viable.
   
   
2. This article is referring to new technology involving enzymes designed to convert the cellulose part of plants to methanol/ethanol. That would mean much more plant bulk available, and it is bulk that is less viable for food.
   
   
3. There are going to be all manner of developments as gene modification advances.
   
   
4. There ain’t no such thing as a free lunch, and I have no clear indication of how much land this will involve, what it would do to the land, etc. Fuel extraction could improve cash crop yields in all manner of situations, for instance poor countries, and provide extra returns for farming in the West.
   
   
5. There are already market, regulation and subsidy pressures tending to drive up the price of biofuels.
   
   
6. Biofuels will increasingly compete with food, and for farmland.
   
   
7. I wonder what impact the removal of a large percentage of cellulosic material will have on soil quality, or soil dpletion.
   
   

Look through this presentation link to the clearer 120-page pdf version of the original PowerPoint presentation.

“[...] lowering the cost of the enzymes needed to turn biomass - wood chips, switch grass and cornhusks - into ethanol to fuel cars. This is crucial work: cellulosic ethanol, as this stuff is called, is far more enviro-friendly than the corn-based brew, and the price of the enzymes needed to break down biomass has already dropped to 30 cents a gallon from as high as $3 per gallon; when the price falls to ten cents a gallon, Stephanopoulos said, it will be fully cost effective [...]” [Quoted from time.com]

the viability of ethanol and cellulosic ethanol

Extracts from a very well researched and mostly reasonable (AP) article.

“Making ethanol is profitable when oil is costly and corn is cheap. And the 51 cent-a-gallon federal subsidy doesn't hurt. But oil prices are off from last year's peaks and corn has doubled in price over the past year, from about $2 to $4 a bushel, thanks mostly to demand from ethanol producers.
—
“America's appetite for corn is enormous. But Americans consume so much gasoline that all the corn in the world couldn't make enough ethanol to slake the nation's lust for transportation fuels. Last year ethanol production used 12 percent of the U.S. corn harvest, but it replaced only 2.8 percent of the nation's gasoline consumption.”
—
“In the end, even the most generous analysts estimate that it takes the energy equivalent of three gallons of ethanol to make four gallons of ...”

Error. The writer means 3 gallons (units) of fossil fuel to make 4 of ethanol.

“... the stuff. Some even argue that it takes more energy to produce ethanol from corn than you get out of it, but most agricultural economists think that's a stretch.”

There are also major considerations of irrigation, land depletion and lowering food availability around the planet. Meat production will also be pressured. It is also driving the tendancy to clear virgin forest.

The full ethanol production of Brazil does not cover one day’s world oil usage, and that production is by the more efficient cane sugar route in a hotter climate.

“Studies suggest that cellulosic ethanol could yield at least four to six times the energy expended to produce it. It would also produce less greenhouse gas emissions than corn-based ethanol because much of the energy needed to refine it could come not from fossil fuels, but from burning other chemical components of the very same plants that contained the cellulose.

The U.S. Department of Energy estimates that the United States could produce more than a billion tons of cellulosic material annually for ethanol production, from switchgrass grown on marginal agriculturallands to wood chips and other waste produced by the timber industry. In theory, that material could produce enough ethanol to substitute for about 30 percent of the country's oil consumption.

“A University of Tennessee study released in November reached similar conclusions. As much as 100 million acres of land would have to be dedicated to energy crops in order to reach the goal of substituting renewable biofuels for 25 percent of the nation's fuel consumption by 2025, the report estimated. That would be a significant fraction ofthe nation's 800 million acres of cultivable land, the study's authors said, but not enough to cause disruptions in agricultural markets.”

what the ipcc did not say - bush, as the crazy corporate socialist

“[...] at current subsidy rates Americans are paying between $2,890 and $3,325 for each tonne of reduction in emissions.”
—
“As the IPCC might have said: "As a result of misguided attempts to mitigate the global climate-change scare we've created, it is extremely likely (with a 99% degree of certainty) that governments will introduce energy-control programs and subsidy regimes for biofuels and other products that have a 70% chance of bringing chaos to other markets, such as food supply. It is very likely such policies, including massive subsidies for corn and mandated ethanol use, will cause prices to rise by as much as 50% and disrupt basic distribution networks, triggering a chain reaction of inflationary forces that would be felt most by vulnerable populations in low-lying urban areas not on the receiving line of massive farm handouts.” [Quoted from www.canada.com/nationalpost]

“Major corporations are cashing in on the subsidies. A recent U.S. government program to promote development of cellulosic ethanol will see funds go to Cargill Inc, E.I. Dupont de Nemours, and Mascoma Corp. In Canada, several companies -- Iogen of Ottawa and Green Field Ethanol -- are among companies set to benefit from the new federal budget. It offered $2-billion in new incentives to ethanol producers. All gasoline must contain 5% "renewable" fuel by 2011. Provincial governments are also goosing the ethanol industry, creating demand for a product that has no economic reason to exist. The U.S. subsidy and regulatory regime is even more outrageous, amounting to US51? a gallon for a product that is now federally mandated.” [Quoted from www.canada.com/nationalpost, page 2]

what the IPCC (4th report, part 2) did say:

“Many estimates of aggregate net economic costs of damages from climate change across the globe (i.e., the social cost of carbon [SCC], expressed in terms of future net benefits and costs that are discounted to the present) are now available. Peer-reviewed estimates of the social cost of carbon for 2005 have an average value of US$43 per tonne of carbon (tC) (i.e., US$12 per tonne of carbon dioxide) but the range around this mean is large. For example, in a survey of 100 estimates, the values ran from US$-10 per tonne of carbon (US$-3 per tonne of carbon dioxide) up to US$350/tC (US$130 per tonne of carbon dioxide [...]” [Quoted from ipcc.ch, p.20 (.pdf) ]

related material
biofuels - reasons for caution

end notes

1. Vinod Khosla, billionaire venture capitalist. Previously was founding CEO of Sun Microsystems.

email email_abelard [at] abelard.org

© abelard, 2007, 26 january
v.1

all rights reserved

the address for this document is https://www.abelard.org/briefings/biofuels.php

2050 words
prints as 6 A4 pages (on my printer and set-up)