Yves here. From time to time, readers will include biofuel on the list of things that could slow the rate of climate change. This post serves as a reminder of why that’s just not so. The only source we know of as an exception is sugar cane, and then only when grown in Brazil. If readers know of any other examples, please pipe up.
By John DeCicco, Research Professor Emeritus, University of Michigan. Originally published at The Conversation
If you’ve pumped gas at a U.S. service station over the past decade, you’ve put biofuel in your tank. Thanks to the federal Renewable Fuel Standard, or RFS, almost all gasoline sold nationwide is required to contain 10% ethanol – a fuel made from plant sources, mainly corn.
With the recent rise in pump prices, biofuel lobbies are pressing to boost that target to 15% or more. At the same time, some policymakers are calling for reforms. For example, a bipartisan group of U.S. senators has introduced a bill that would eliminate the corn ethanol portion of the mandate.
Enacted in the wake of the attacks of Sept. 11, 2001, the RFS promised to enhance energy security, cut carbon dioxide emissions and boost income for rural America. The program has certainly raised profits for portions of the agricultural industry, but in my view it has failed to fulfill its other promises. Indeed, studies by some scientists, including me, find that biofuel use has increased rather than decreased CO2 emissions to date.
Current law sets a target of producing and using 36 billion gallons of biofuels by 2022 as part of the roughly 200 billion gallons of motor fuel that U.S. motor vehicles burn each year. As of 2019, drivers were using only 20 billion gallons of renewable fuels yearly – mainly corn ethanol and soybean biodiesel. Usage declined in 2020 because of the pandemic, as did most energy use. Although the 2021 tally is not yet complete, the program remains far from its 36 billion-gallon goal. I believe the time is ripe to repeal the RFS, or at least greatly scale it back.
Higher Profits for Many Farmers
The RFS’s clearest success has been boosting income for corn and soybean farmers and related agricultural firms. It also has built up a sizable domestic biofuel industry.
The Renewable Fuels Association, a trade group for the biofuels industry, estimates that the RFS has generated over 300,000 jobsin recent years. Two-thirds of these jobs are in the top ethanol-producing states: Iowa, Nebraska, Illinois, Minnesota, Indiana and South Dakota. Given Iowa’s key role in presidential primaries, most politicians with national ambitions find it prudent to embrace biofuels.
The RFS displaces a modest amount of petroleum, shifting some income away from the oil industry and into agribusiness. Nevertheless, biofuels’ contribution to U.S. energy security pales compared with gains from expanded domestic oil production through hydraulic fracturing – which of course brings its own severe environmental damages. And using ethanol in fuel poses other risks, including damage to small engines and higher emissions from fuel fumes.
For consumers, biofuel use has had a varying, but overall small, effect on pump prices. Renewable fuel policy has little leverage in the world oil market, where the biofuel mandate’s penny-level effects are no match for oil’s dollar-scale volatility.
Prices for #ethanol have surged, rekindling a debate about whether it’s contributing to pain at the pump and whether the White House should relax ethanol-blending regulations https://t.co/DUcvnStlR1
— Farm Policy (@FarmPolicy) November 24, 2021
Biofuels Are Not Carbon-Neutral
The idea that biofuels are good for the environment rests on the assumption that they are inherently carbon neutral – meaning that the CO2 emitted when biofuels are burned is fully offset by the CO2 that feedstocks like corn and soybeans absorb as they grow. This assumption is coded into computer models used to evaluate fuels.
Leading up to passage of the RFS, such modeling found modest CO2 reductions for corn ethanol and soybean biodiesel. It promised greater benefits from cellulosic ethanol – a more advanced type of biofuel that would be made from nonfood sources, such as crop residues and energy crops like willow and switchgrass.
But subsequent research has shown that biofuels are not actually carbon-neutral. Correcting this mistake by evaluating real-world changes in cropland carbon uptake reveals that biofuel use has increased CO2 emissions.
One big factor is that making biofuels amplifies land-use change. As harvests are diverted from feeding humans and livestock to produce fuel, additional farmland is needed to compensate. That means forests are cut down and prairies are plowed up to carve out new acres for crop production, triggering very large CO2 releases.
Expanding farmland for biofuel production is also bad for the environment in other ways. Studies show that it has reduced the abundance and diversity of plants and animals worldwide. In the U.S., it has amplified other adverse impacts of industrial agriculture, such as nutrient runoff and water pollution.
The Failure of Cellulosic Ethanol
When Congress expanded the biofuel mandate in 2007, a key factor that induced legislators from states outside the Midwest to support it was the belief that a coming generation of cellulosic ethanol would produce even greater environmental, energy and economic benefits. Biofuel proponents claimed that cellulosic fuels were close to becoming commercially viable.
Almost 15 years later, in spite of the mandate and billions of dollars in federal support, cellulosic ethanol has flopped. Total production of liquid cellulosic biofuels has recently hovered around 10 million gallons per year – a tiny fraction of the 16 billion gallons that the RFS calls for producing in 2022. Technical challenges have proved to be more daunting than proponents claimed.
Environmentally speaking, I see the cellulosic failure as a relief. If the technology were to succeed, I believe it would likely unleash an even more aggressive global expansion of industrial agriculture – large-scale farms that raise only one or two crops and rely on highly mechanized methods with intensive chemical fertilizer and pesticide use. Some such risk remains as petroleum refiners invest in bio-based diesel production and producers modify corn ethanol facilities to produce biojet fuel.
Ripple Effects on Lands and Indigenous People
Today the vast majority of biofuels are made from crops like corn and soybeans that also are used for food and animal feed. Global markets for major commodity crops are closely coupled, so increased demand for biofuel production drives up their prices globally.
This price pressure amplifies deforestation and land-grabbing in locations from Brazil to Thailand. The Renewable Fuel Standard thus aggravates displacement of Indigenous communities, destruction of peatlands and similar harms along agricultural frontiers worldwide, mainly in developing countries.
Some researchers have found that adverse effects of biofuel production on land use, crop prices and climate are much smaller than previously estimated. Nevertheless, the uncertainties surrounding land use change and net effects on CO2 emissions are enormous. The complex modeling of biofuel-related commodity markets and land utilization is impossible to verify, as it extrapolates effects across the globe and into the future.
Rather than biofuels, a much better way to address transportation-related CO2 emissions is through improving efficiency, particularly raising gasoline vehicle fuel economywhile electric cars continue to advance.
A Stool with Two Weak Legs
What can we conclude from 16 years of the RFS? As I see it, two of its three policy legs are now quite wobbly: Its energy security rationale is largely moot, and its climate rationale has proved false.
Nevertheless, key agricultural interests strongly support the program and may be able to prop it up indefinitely. Indeed, as some commentators have observed, the biofuel mandate has become another agribusiness entitlement. Taxpayers probably would have to pay dearly in a deal to repeal the RFS. For the sake of the planet, it would be a cost worth paying.
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Using food crops (i.e. starch) to produce ethanol was always crazy. Only cellulose biofuel makes sense – i.e. using either waste material from food production. And unfortunately its proven far more difficult than was thought – nobody so far as I’m aware has come up with an economically viable way of doing it, although hardly a month goes by without an article in one of the main science magazines claims that a breakthrough has been made. Unfortunately, cellulose/waste biofuel falls into the category of ‘it will be viable in 5 years, just like it has been for the past 25 years’.
I don’t think a blanket opposition to biofuels is justified. The use of grasses (including bamboo) could allow sustainable and profitable growing in areas which are not suitable for other forms of agriculture, especially on heavily degraded tropical soils. But this depends on a whole chain of processes, from growing to production to market demand being put in place, and this doesn’t seem likely in the immediate future. As so often with renewables, the problem is not the technology or the economics, its fitting all the supply parts into place. There is often a circular argument going on – the potential users won’t invest unless they have a guarantee of supply and the potential suppliers won’t invest until they have a guarantee of demand….
The reason biofuels should not be immediately dismissed is that in a rapid transition it will in many cases be far more efficient to use existing power plant rather than replace it. There are countless internal combustion engines out there in cars, trucks, aircraft and ships and it will be impossible to replace them all in the timescale needed. So at least part of the transition means replacing the existing fuel, rather than the combustion plant. This can only be done by a combination of using renewable energy to create fuels such as hydrogen or ammonia for use in existing fuel streams and adding at least some level of synthetic biofuel into the mix.
Just for clarity, it should be noted that the problems addressed above are specific to liquid biofuels. There are plenty of economically viable biofuels, most obviously methane produced in various forms of bioreactors or gasification plants, mostly using a variety of waste products. These have been economically viable for years and are commonly used all over the world, usually in farms or within landfill operations.
Can enough liquid bio-fuel be grown in a year to replace all the liquid fossil fuel used in a year? Or can liquid bio-fuel only provide a tiny fraction in one year of what liquid fossil fuel is burned in a year? How do the two amounts compare?
Because if liquid bio-fuel can only grow a fraction in a year as much fossil liquid-fuel is pumped up and burned in a year, then the only way that liquid bio-fuel could replace liquid fossil-fuel is if the use of liquid fossil fuel is strangled back down to what liquid bio-fuel can provide.
As to agricultural “waste”, its only “waste” if its wasted. If all that “waste” were turned into biochar and mixed back into the soil its source-crops came from, the biochar-enhanced soil could grow a larger amount of agriculture biomass, the “waste” from which could be turned into a still larger amount of biochar to mix back into the soil which could grow an even larger amount of agricultural biomass, the “waste” from which could produce an even larger amount of biochar which, when mixed into the soil, could allow that soil to grow a still more larger yet amount of agricultural biomass, and so forth and so on, upward and upward and upward.
But we can’t do that if we waste all the agricultural “waste” on degrading it into more mere fuel. And of course Gabe Brown and others might suggest grinding up and drying that “waste” to apply to the soil surface as “armor on the soil” at all the right times in the farming cycle.
Hm, I think that biofuels can’t seamlessly replace fossil fuels, but every fraction that they do replace is a fraction that doesn’t need austerity, so as long as they are better then that’s progress. I agree ethanol is a boondoggle but biodiesel has potential if something like a carbon tax makes it economically viable.
That would be part of why Hansen suggested the fossil Fuel FeeTax Dividend the way he suggested it.
This when mandated was a gift to senator Grassleys base of corn farmer voters. They had run out of new ways to use their record breaking corn crops. The price of corn dropped drastically because of a surplus. I was suspicious at that time the mandate wouldn’t live up to its promises. There were negatives that were swept under the table. One was the ethanol mix reduced a cars mpg. At first there were also performance issues in cars. Longevity was another issue. Then you had major issues with small engines, like those in lawnmowers , chain saws, and other small engine products. Probably issues in these products were even worse than in cars. I purchase non ethanol gas to use in all of my small engine products. It’s amazing how much better they perform. I think the public is being misled by all of the hype over electric vehicles, not unlike the promoting of ethanol in gasoline.
A few points on ethanol and biofuels:
1) The original push for US biofuels came before 9/11 from the romantic left.
2) A Google search for “Energy in 1 gallon of ethanol vs one gallon of gasoline” yields: “1.5 US gallons (5.7 litres) of ethanol has the same energy content as 1.0 US gal (3.8 l) of gasoline. A flex-fuel vehicle will experience about 76% of the fuel mileage MPG when using E85 (85% ethanol) products as compared to 100% gasoline.” Ethanol is used to water gasoline.
3) Brazil had a lot of sugar cane and post-1973 decided it would substitute for expensive gasoline in cars. It worked. But the more recent increase in sugar planting in Brazil and I assume Thailand is for sugar-to-calories-for humans… all those corn oil products being used to fatten up US consumers and poor people around the world can be made with cane sugar. Palm oil is the competition.
4) The post 9/11 DC joke was that Iowa had excess corn and that it could be used to either lower the price of beef or make ethanol via a catalyst called ICV- “Iowa Caucus Votes”. We did the latter, then in the usual mission creep, the sugar lobby first in Louisiana then in Jamaica (remember the Caribbean Basin Initiative?) got their noses under the tent. Jamaica built very large sugar cane processing facilities- apparently bigger than were needed to process the island’s cane. So where did the rest of the cane come from? Rumors said “Cuba” although I can’t verify that story- only one source. The only way to end the ethanol-to-fuel scam is to buy-off Iowa voters with transitional money to expand animal products production and lower beef costs for consumers.
5) Converting forest waste and grass into “free” biofuel is old technology. In Alabama- the piney woods belt- you’d boil wood scraps with catalysts in what were called “black liquor recovery boilers”, which broke the lignin bonds and gave you fuel to power the industry. The boilers were temperamental and prone to explode and gave the region that unique “sweet” smell I remember from the late 1960s. Rust Engineering of AL was the leading designer of these plants, so Yves grew up in that world.
6) “Grassley”. What a wonderful name for an Iowa Senator. We need a Senator from Texas named Petrovich. Rhode Island should have one named “Little”… although RI’s Senator Reed will do.
I assume the “expanded animal products” production refers to petrochemical GMO shitmeat production from CAFO animals?
Would people be prepared to pay more for meat if all the cornland in Iowa were converted into multi-species pasture systems for growing lower amounts of shinola beef at higher prices? For a higher quality of grassfed shinola beef?
If not, then I guess we will just roll merrily along until all the topsoil and then subsoil is eroded off on Iowa and into the Gulf of Mexico, and Iowa is eroded all the way down to whatever undersubsoil lies beneath the subsoil.
Surely there must be an Armenian somewhere with the last name ” Petrolian”. Maybe he could run for Senator from Texas.
I hadn’t heard of the sugarcane thing. The only completely sustainable “biofuel” I know of is food. It works like this: you grow/harvest/hunt some food, then you eat the food, then you use your muscles to perform work. It works with just about any plant matter, really, if you can get the right animal companions involved.
How much of the major US agricultoral crop goes to make fuel?
https://afdc.energy.gov/data/10339
The end use of the corn is divided into 3 roughly equal parts: human food-product use, livestock feed, and ethanol. At this point it’s pretty well entrenched politically. Until natural gas stops being cheap, which is ultimately what determines if gasoline refiners can make a few pennies blending in the ethanol, there’s no stopping it in federal policy.
If the PrezNom primary process is not a complete sham, then a PrezNom wannabe could run the following experiment . . . . boycott the Iowa Primary and/or the Iowa Caucuses. Only run in later primaries and caucuses and make a basic part of herm’s platform that if nominated, heeshee will run on the basis of abolishing the forced gasohol mandate and will work to elect a Congress step by step, election by election, which will vote to abolish all subsidies to petrochemical GMO shitcorn production in order to stop the agribiz shitcorn producers from eroding Iowa down to whatever bare rock lies beneath the soil, subsoil and undersubsoil.
Make it an issue and break Iowa’s undeserved veto over what candidates even get to go on to New Hampshire and South Carolina. That’s a first step to breaking the gasohol mandate and then breaking the petrochemical GMO shitcorn subsidies.
How much of the shitcorn gasohol money even stays with the farmers who harvest it? How much of that money do those farmers then have to pay right back out for all the petrochemical GMO inputs needed to grow the petrochemical GMO shitcorn? To what extent are these farmers merely a money-conduit right back out to the agribiz input conspiracy which has been deepening its colonial control of agriculture ever since WWII?
Would those farmers retain more money from a shinola cattle on shinola pasture than what they retain now after all the expense of producing shitcorn alcohol?
Another harm caused by putting ethanol into gas it that it make small motors, lawn mowers, chain saws, etc. run less well. Going back to ethanol free gas would be a small boon to rural areas especially.
Making engines “run less well” is a subject that warrants further discussion. When ethanol causes corrosion or fouling in a gasoline engine (thereby making it “run less well”), it causes it to burn more fuel (and thereby increase CO2 emissions) and to run dirtier (and thereby increase other pollutants). These increases in fuel consumption and pollution could easily outweigh the benefits that ethanol supplementation was supposed to provide.
And it’ll get even worse if we permit E15 fuel instead of just E10 fuel. Not only would small engines be negatively impacted to a greater degree, but millions of older (and much larger and more frequently operated) automobile engines that were only designed for E10 will also suffer harm.
Well, that would force people to buy electric cars sooner or go without cars altogether, if their engines are carefully destroyed by a cynical and sinister E15 mandate secretly imposed for just exactly that purpose. Because what other purpose would it be imposed for, except for further enriching the input suppliers who will recieve the even-more money circling back to them through their captive cash-conduit farmers?
if their engines are carefully destroyed by a cynical and sinister E15 mandate secretly imposed for just exactly that purpose. Because what other purpose would it be imposed for
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You have your facts wrong. Engines would last longer on higher ethanol blends.
https://theindependent.com/opinion/editorial/unl-study-e30-doesn-t-cut-fuel-efficiency-or-damage-vehicles/article_0b1680ae-8114-11eb-ba6a-87271ad6d3db.html
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The question is not whether higher concentration will be mandated. The question is will the govt allow higher levels of ethanol to be sold. Currently the EPA interprets the Renewable Fuel Standard to limit the amount ethanol made from corn to 10% of the total. If the EPA allowed ethanol producers to sell more, that would happen very quickly. Motorists would buy more, the only thing stopping them is the Govt does not allow it.
If Grumpy Engineer is wrong about higher per cent ethanol harming engines faster, then that particular issue is a non-problem.
The destruction of land and habitats for agri-alcohol would still be a problem, especially given that we could only grow at best a fraction per year of biomass alcohol as what we burn per year from fossil fuels.
So less use of liquid fuels will be imposed by impersonal reality if no human-based self-imposition of using less doesn’t come first.
Making engines “run less well” is a subject that warrants further discussion.
It certainly is a subject that warrants discussion. Ethanol does not make engine run less well. Just the opposite. Ethanol is added because the base blend stock fuel is what makes spark ignition engines “run less well” . Ethanol is the cheapest method for bringing that lousy base fuel up to grade so that can be used in modern engines. Motorists can choose not to put ethanol into their tanks. They choose ethanol because it is cheaper.
Removing the federal govt mandates won’t change the physics and economics of fuel and engine design. The govt will have to outlaw the use of ethanol to get rid of it, because motorists will continue to buy ethanol blends if given a choice.
jinn. You could not be more wrong; i.e. “Ethanol does not make engine run less well”. This product, if we can even call it that, has ruined untold numbers of small engines and led to many expensive repairs in older cars based on my own direct experience. Our local Triumph (sports car) Club has held many a tech session over the years on how to deal with issues created by ethanol and many of us have to drive miles out of our way to find ethanol free gas or buy expensive additives/stabilizers. Put some ethanol gas in a clear glass container and leave it sit for a week or so and you will readily see what is called “phase separation” – the fuel will separate into water and fuel. Another tell tale sign of what this stuff does is the algae we find around the gas cap of our cars nowadays. Ethanol is the lousy fuel in modern gas and I would choose ethanol free gas anytime I have a choice.
This product, if we can even call it that, has ruined untold numbers of small engines
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That is just evidence free story. I have several small engines that have run well for 40 years on ethanol blends. That’s right, where I live ethanol blends have been available since 1976. 100 years ago , Henry Ford recommended using ethanol blends because Ford testing showed that the model T ran better on ethanol blends and lasted longer.
You probably also believe that putting lead in gasoline was good for engines. The oil company and govt propaganda convinced people to poison themselves and destroy their engines with lead for more than 50 years. Then after that came the additive MTBE which was also destructive to human health and engines.
Some facts about how the EPA has persistently sabotaged the use of ethanol in motor fuels:
~If motorists were given the choice to buy higher ethanol blends, they probably would. The Renewable Fuel Standards gives the EPA authority to cap the amount of ethanol allowed to be sold as fuel and the EPA has used that authority to block all expansion of US domestic ethanol sales since 2014.
~All vehicles made for the US market have been designed to be able to run well on ethanol blends since the mid 70’s. The reason for this is that when lead free gasoline was introduced the oil companies used the additive MTBE as the replacement for lead. MTBE is a product similar to alcohol made from fossil fuels that is far more corrosive (and toxic) than ethanol. As a consequence auto manufacturers started using elastomers and metals in fuel systems that are more than adequate to handle ethanol. Up until about 2010 lead free gasoline with MTBE really did damage to small engines and older vehicles. However, the EPA does not allow automakers to make warranty or performance claims that pass any of this information on to motorists.
~The EPA prohibits automakers from making warranty, performance and fuel efficiency claims based on how well their vehicles perform on ethanol blends. The EPA protects automakers from liability for any claims they make based on testing using a special fuel that is commercially available nowhere in the US. If automakers make claims based on tests using real world fuels that motorists are actually using, they lose that liability protection and likely will be sued by the EPA instead.
~ Even flex fuel vehicles are subject to these byzantine standards by the EPA. Auto makers are required to test their flex vehicles using what the EPA calls ethanol free conventional gasoline (not the same as conventional gas available in some places) and then from that data the fuel economy, performance and CHG emissions that the automaker is allowed to advertise must be calculated based on formulas created by the EPA. Not allowing Flex vehicles to actually be designed to perform best on E85 gasoline completely defeats the purpose of having flex vehicles. Its like requiring diesel engines to be tested on gasoline and then requiring the engine maker to use that bogus test data to calculate the diesel performance for the purpose of informing the public.
Micro-algae has a lot of promise in theory. No-one has really cracked the practical difficulties yet though, and when they do big business will find a way to do it in the most damaging way possible.
Planting jatropha hedges round your fields may provide enough biodiesel to run your farm. This is not technically challenging but the danger is you might find it more profitable to grow jatropha than food.
Would jatropha grow in non-tropical or even non-subtropical areas?
One could plant trees and/or shrubs growing nuts or fruits super-rich in flammable oil, such as olive trees, tung trees, bitternut hickory trees, etc. And one could grow them on land too hilly to grow row crops. And one could grow them in alleys or individually far apart enough from eachother to where multispecies pasture and range could be grown under and around the fuel oil trees while shinola cattle graze on the shinola pasture under and around the biodiesel fuel trees. Biodiesel silviculture!
That could only work if society were to cut its desire for biodiesel fuel down to what biodiesel fuel trees could supply, even as the same land is also supplying grass-feed shinola beef while sucking down skycarbon and bio-storing it into the soil under the whole system.
https://en.wikipedia.org/wiki/Tung_oil
https://www.britannica.com/plant/tung-tree
https://www.staroilco.net/biodiesel-feedstocks-sunflower-oil-tung-oil/
Jatropha needs warm and wet. It can tolerate drought, even prefers a dry season, but not frost. Florida could work.
It hasn’t really been domesticated yet so I guess there is some scope for tuning. They bred a non-toxic variety in Mexico.
I wonder if olive trees could be bred for more oil production of merely fuel quality. How much of the energy the olive tree spends on making olives is spent on making the flavor chemicals which give olive oil its taste and flavoroma? If all that energy were devoted strictly to making more olive oil which tasted like canola oil in the olives, would it amount to rather more oil per olive?
And are olive trees dry-requiring or merely dry-tolerant? If merely dry-tolerant, could growing them in somewhat more soil-water-retentive conditions or management also result in more photosynthesis leading to more energy to dump into more oil in more olives?
Meanwhile, of course, doing between-the-tree growing of food crops, maybe focusing on grasses for animal grazing between the olive trees.
Olives normally need a dryish mediterranean climate but I have seen one bearing in an English graveyard and the Brazilians have bred a tropical one. Don’t know what the oil of either is like though.
If that one in the English graveyard bears many pounds of olives, one could gather them all and press/crush them for just enough oil to see what their oil is like.
Or once could gather them and treat them exactly as the Mediterranian people do and see if they make good “Greek olives”.
If these trees withstand enough subfreezing weather to be called “winter” however mild, then they may be worth propagating and spreading around.
all advertised green energies are supported by the FF industry !
America could have been free of hydro & FF electric generation in 1975 or earlier by developing thorium liquid salt electric gen>, It’s a 24-7 gen that America’s for profit electric utilities will never buy into because they are a for profit utility! They loose if electricity were to be costing less!
In a for profit economy nobody will ever volunteer to make less profit the FF industry influences agriculture and peoples wants thru advertising to keep us using cotton masses of paper products and mailers all industries are encouraged to use more FF influenced products as well as building products for shorter useful life making you buy a replacement long befor it should have worn out! all of this helps the FF industry more than any other!
All equipment built for any use is heavier than need be so more FF will be needed to power it I have experiance with some agriculture equipment , american made is heavier but not longer lasting than asian or europian designs because FF inf has paid engineers working fot american farm equipment designing teams! Even our trains & busses are forced to be heavier so they require bigger engins ! No aspect of mass transit has low weight high effeciency equipment in their view because they are underwritten by the FF Ind! If you want a roadmap of things to come look to history anf the tobacco industries successful extention of sales ,using them as a model the FF ind. is manipulating every link in to chain to expand & increase the use of FF’s!
yess there is more! 304461350
A perennial oilseed crop that would keep roots in the ground all year long while providing additional wildlife habitat to replace some acres of annual row crops would be a great start…… Agroforestry….. J Russell Smith, Tree Crops…
Olive trees? Tung trees? Bitternut hickory trees?
There was a time when non-ethanol cellulosic biofuels may have made sense; i.e. when the world’s population was 2 billion (when the promise of biomass conversion technology didn’t exist), but that window has closed because the energy density of any biofuel produced ON A LAND AREA BASIS (gigajuels/ha/year), and taking into account all of the energy losses in the conversion processes, compared crude oil pumped from a 1/2 ha pump jack plot, is so minuscule as to be ridiculously uneconomic. Its 3 to 4 orders of magnitude smaller. Arable land is an exponentially vanishing thing – inversely proportional to the exponential growth of the human population. Even when “experts” niggle the conversation about the pollution benefits from biofuels, they do so (deliberately) ignoring the cost of the other vanishing resource – water – for irrigation, processing, or toxic waste water from algae. The notion that non-food biofuel feedstock could be grown on “marginal land” (e.g. forest thinnings, or grasses on CRP land) fails when extraction, transport, and land remediation are accounted for and ignoring the recovered energy density of the fuel product on a land area basis.
Nope, the biofuel ship has sailed. Too many energy consumers and not enough land…IMHO. We’re riding this population overshoot ship into a dark future.