Peak
Soil: Why Cellulosic and other Biofuels are
Not Sustainable
and a Threat to America’s National Security
By Alice Friedemann Last updated May 30, 2007
http://www.energyskeptic.com/Peak_Soil.htm
“The nation that
destroys its soil destroys itself”, President Franklin D. Roosevelt
There's growing public attention from the people, all the
way on down to the President, about biomass potential for energy. There's been a public discussion about many
aspects and what the problems might be.
But there's one aspect of all of this that is conspicuous by its absence
- a national discussion of anything about the soil science - the effect growing
row crops like corn and soy have on the land and water.
Whatever biomass we're going to grow, there are important
issues about net energy gain and the carbon balance, but we also need to deal
with the root of the matter - the soils, and water, and whether growing biomass
for fuel can be made sustainable.
The lack of any kind of input on this by soil scientists about how we're mining our soils is a voice that needs to be heard, because if you destroy the soil, you can't grow biomass.
Part 1. The
Dirt on Dirt.
Ethanol is an agribusiness get-rich-quick scheme that will bankrupt our topsoil.
Nineteenth century
western farmers converted their corn into whiskey to make a profit (Rorabaugh
1979). Archer Daniels Midland, a large
grain processor, came up with the same scheme in the 20th
century. But ethanol was a product in
search of a market, so ADM spent three decades relentlessly lobbying for
ethanol to be used in gasoline. Today ADM makes record profits from ethanol
sales and government subsidies (Barrionuevo 2006).
The Department of
Energy hopes to have biomass supply 5% of the nation’s power, 20% of
transportation fuels, and 25% of chemicals by 2030. These combined goals are
30% of the current petroleum consumption (DOE Biomass Plan, DOE Feedstock Roadmap).
Fuels made from
biomass are a lot like the nuclear powered airplanes the Air Force tried to
build from 1946 to 1961, for billions of dollars. They never got off the
ground. The idea was interesting –
atomic jets could fly for months without refueling. But the lead shielding to protect the crew
and several months of food and water was too heavy for the plane to take
off. The weight problem, the ease of
shooting this behemoth down, and the consequences of a crash landing were so
obvious, it’s amazing the project was ever funded, let alone kept going for 15
years.
Biomass fuels have equally obvious and predictable reasons for failure. Odum says that time explains why renewable energy provides such low energy yields compared to non-renewable fossil fuels. The more work left to nature, the higher the energy yield, but the longer the time required. Although coal and oil took millions of years to form into dense, concentrated solar power, all we had to do was extract and transport them (Odum 1996)
With every step required to transform a fuel into energy, there is less and less energy yield. For example, to make ethanol from corn grain, which is how all ethanol is made now, corn is first grown to develop hybrid seeds, which next season are planted, harvested, delivered, stored, and preprocessed to remove dirt. Dry-mill ethanol is milled, liquefied, heated, saccharified, fermented, evaporated, centrifuged, distilled, scrubbed, dried, stored, and transported to customers (McAloon 2000).
Fertile soil will be destroyed if crops and other “wastes”
are removed to make cellulosic ethanol.
“We stand, in most places on earth, only six inches from
desolation, for that is the
thickness of the topsoil layer upon which the entire life of the planet
depends” (Sampson 1981).
Loss of topsoil has been a major factor in the fall of
civilizations (Sundquist 2005
Chapter 3, Lowdermilk 1953, Perlin 1991, Ponting 1993). You end up with a country like
Fuels from biomass
are not sustainable, are ecologically destructive, have a net energy loss, and
there isn’t enough biomass in America to make significant amounts of energy
because essential inputs like water, land, fossil fuels, and phosphate ores are
limited.
Soil Science 101 – There Is No “Waste” Biomass
Long before there was “Peak Oil”, there was “Peak Soil”.
Productivity drops off sharply when topsoil reaches 6
inches or less, the average crop
root zone depth (Sundquist 2005).
Crop productivity continually declines as topsoil is lost
and residues are removed. (Al-Kaisi May 2001, Ball 2005, Blanco-Canqui 2006, BOA 1986, Calviño 2003, Franzleubbers 2006, Grandy 2006,
Johnson 2004, Johnson 2005, Miranowski 1984, Power 1998, Sadras 2001, Troeh
2005, Wilhelm 2004).
On over half of America’s best crop land, the erosion rate is 27 times the natural rate, 11,000 pounds per acre (NCRS 2006). The
natural, geological erosion rate is about 400 pounds of soil per acre per year (Troeh
2005). Some is due to farmers not being
paid enough to conserve their land, but most is due to investors who farm for
profit. Erosion control cuts into
profits.
Erosion is happening ten to twenty times faster than the
rate topsoil can be formed by natural processes (Pimentel 2006). That might make
the average person concerned. But not
the USDA -- they’ve defined erosion as the average soil loss that could occur
without causing a decline in long term productivity.
Troeh (2005) believes that the tolerable soil loss (T)
value is set too high, because it's
based only on the upper layers -- how long it takes subsoil to be converted
into topsoil. T ought to be based on
deeper layers – the time for subsoil to develop from parent material or parent
material from rock. If he’s right,
erosion is even worse than NCRS figures.
We've come a long
way since the 1930's in reducing erosion, but that only makes it more
insidious. Erosion is very hard to
measure -- very little soil might erode for years, and then tons per acre blown
or washed away in an extreme storm just after harvest, before a cover crop has
had a chance to protect the soil. We
need better ways of measuring and monitoring erosion, since estimates wildly
differ (Trimble 2000).
Erosion removes the most fertile parts of the soil (USDA-ARS).
When you feed the soil with organic matter, you’re not feeding plants;
you’re feeding the biota in the soil. Underground creatures and fungi break down
fallen leaves and twigs into microscopic bits that plants can eat, and create
tunnels air and water can infiltrate. In
nature there are no elves feeding (fertilizing) the wild lands. When plants die, they’re recycled into basic
elements and become a part of new plants.
It’s a closed cycle. There is no
bio-waste.
Soil creatures and fungi act as an immune system for
plants against diseases, weeds, and
insects – when this living community is harmed by agricultural chemicals and
fertilizers, even more chemicals are needed in an increasing vicious cycle (Wolfe
2001).
There’s so much life in the soil, there can be 10
“biomass horses” underground for every horse grazing on an acre of pasture (Hemenway 2000). The June 2004 issue of
Science calls soils “The Final Frontier”.
Just a tiny pinch of earth could have 10,000 different species (Wardle
2004) -- millions of creatures, most of them unknown. If you dove into the soil and swam around,
you’d be surrounded by thousands of miles of thin strands of mycorrhizal fungi that
help plant roots absorb more nutrients and water (Pennisi 2004). As you swam along, plant roots would tower
above you like trees as you wove through underground skyscrapers.
Plants and creatures underground need to drink, eat, and
breathe just like we do. An ideal soil is half rock, and a quarter
each water and air. When tractors plant
and harvest, they crush the life out of the soil, as underground apartments collapse
9/11 style. The tracks left by tractors in the soil are
the erosion route for half of the soil that washes or blows away (Wilhelm
2004).
Corn Biofuel (i.e. butanol, ethanol, biodiesel) is especially
harmful because:
These practices lead to lower crop production and
ultimately deserts. Growing plants
for fuel will accelerate the already unacceptable levels of topsoil erosion, soil
carbon and nutrient depletion, soil compaction, water retention, water
depletion, water pollution, air pollution, eutrophication, destruction of
fisheries, siltation of dams and waterways, salination, loss of biodiversity,
and damage to human health (Tegtmeier
2004).
Why are soil scientists absent from the biofuels
debate?
I asked 35 soil
scientists why topsoil wasn’t part of the biofuels debate. These are just a few of the responses from
the ten who replied to my off-the-record poll (no one wanted me to quote them,
mostly due to fear of losing their jobs):
This is not a new debate. Here’s what scientists had to say decades ago:
Removing “crop residues…would rob organic matter that is vital to the maintenance of soil fertility and tilth, leading to disastrous soil erosion levels. Not considered is the importance of plant residues as a primary source of energy for soil microbial activity. The most prudent course, clearly, is to continue to recycle most crop residues back into the soil, where they are vital in keeping organic matter levels high enough to make the soil more open to air and water, more resistant to soil erosion, and more productive” (Sampson 1981).
“…Massive alcohol production from our farms
is an immoral use of our soils since it rapidly promotes their wasting
away. We must save these soils for an
oil-less future” (
Gasohol was made so poorly in the 80's that the name was
changed to ethanol.
What the USDA knew
about continuous corn in 1911:
"When the rich, black, prairie corn lands of the Central West were first broken up, it was believed that these were … inexhaustible lands … So crop after crop of corn was planted on the same fields. There came a time, however, after 15 or 20 years, when the crop did not respond to cultivation; the yields fell off and the lands that once produced 60-70 bushels per acre annually dropped to 25 to 30 bushels.
… With the passing years, the soil became more compact, droughts were more injurious, and the soil baked harder and was more difficult to handle. Continuous corn culture has no place in progressive farming...it is a shortsighted policy and is suicidal on lands that have been long under cultivation" (Smith 1911).
Natural Gas in Agriculture
“Fertilizer energy” is 28% of the energy used in
agriculture (Heller, 2000). Fertilizer uses natural gas both as a
feedstock and the source of energy to create the high temperatures and
pressures necessary to coax inert nitrogen out of the air (nitrogen is often
the limiting factor in crop production).
Fertilizers only replace nutrition. They
don't provide the ecosystem services that organic matter does. Organic matter is known as “waste” in the
biofuels industry.
Organic matter slows
erosion and fixes carbon in the soil.
Dead plants and the soil biota that feed on them create channels that
let air and water get to plant roots, which breathe and drink just like we
do. The soil retains water, helping
plants get through droughts.
Organic matter
provides food for the soil biota, which provide an immune system for
plants. The mycorrhizal fungi in the
soil provide plants extra nutrients and water in exchange for sugars.
Fertilizer not only provides no ecosystem services, it
harms the ecosystem. Fertilizer disables or kills some of the
creatures in the soil web, which increases the need for agrichemicals in an
increasingly vicious cycle.
Fertilizers increase global warming, acid rain, and
eutrophication.
You can grow
tomatoes on rocks if you dump enough fertilizer on them. But doing so depletes
the soil, we mine it when we do this.
Fertilizer represents 28% of the energy used in
agriculture. So let me get this straight. Fertilizers are made from and with natural
gas which we’re dumping on crops to grow them for biofuel. We’re going to take the biomass waste away,
which means we’ll have to add even more fertilizer. How, exactly, does that
lessen our dependence on fossil fuels?
OK, one good thing, sort of. Fertilizer is part of the green revolution that made it possible for
the world’s population to grow from half a billion to 6.5 billion today (Smil
2000, Fisher 2001). So I’m biting the
hand that feeds me and four billion plus others who wouldn’t be alive
otherwise. But natural gas is limited, not
easily imported, and it’s depleting faster than oil on the North American
continent. Discontinuities clearly lie ahead.
Our national security is at risk as we deplete our
aquifers and become dependent on unstable foreign states to provide us with
increasingly expensive fertilizer. Between 1995 and 2005 we increased our
fertilizer imports by more than 148% for Anhydrous Ammonia, 93% for Urea
(solid), and 349 % of other nitrogen fertilizers (USDA ERS). Removing crop residues will require large
amounts of imported fertilizer from potential cartels, potentially so expensive
farmers won’t sell crops and residues for biofuels.
Improve national security and topsoil by returning
residues to the land as fertilizer.
We are vulnerable to high-priced fertilizer imports or “food for oil”, which
would greatly increase the cost of food for Americans. Return crop residues to the soil to provide
organic fertilizer, don’t increase the need for natural gas fertilizers by
removing crop residues to make cellulosic biofuels.
Part 2. The Poop on Ethanol:
Energy Returned on Energy
Invested (EROEI)
To understand the concept of EROEI, imagine a magician doing a variation on the rabbit-out-of-a-hat trick. He strides onstage with a rabbit, puts it into a top hat, and then spends the next five minutes pulling 100 more rabbits out. That is a pretty good return on investment!
Oil was like that in the beginning: one barrel of oil energy was required to get 100 more out, an Energy Returned on Energy Invested of 100:1.
When the biofuel magician tries to do the same trick decades later, he puts the rabbit into the hat, and pulls out only one pooping rabbit. The excrement is known as byproduct or coproduct in the ethanol industry.
Studies that show a positive energy gain for ethanol would have
a negative return if the byproduct were left out (Farrell 2006). Here’s where byproduct comes from: if you
made ethanol from corn in your back yard, you’d dump a bushel of corn, two
gallons of water, and yeast into your contraption. Out would come 18 pounds of ethanol, 18
pounds of CO2, and 18 pounds of byproduct – the leftover corn solids.
Patzek and Pimentel believe you shouldn’t include the energy contained in the byproduct, because you need to return it to the soil to improve nutrition and soil structure (Patzek June 2006). Giampetro believes the byproduct should be treated as a “serious waste disposal problem and … an energy cost”, because if we supplied 10% of our energy from biomass, we’d generate 37 times more livestock feed than is used (Giampetro 1997).
It’s even worse than he realized – Giampetro didn’t know most
of this “livestock feed” can’t be fed to livestock because it’s too energy and
monetarily expensive to deliver – especially heavy wet distillers byproduct, which
is short-lived, succumbing to mold and fungi after 4 to 10 days. Also, byproduct
is a subset of what animals eat. Cattle are
fed byproduct in 20% of their diet at most.
Worst of all, the EROEI of ethanol is 1.2:1 or 1.2 units of energy out for every unit of energy in, a gain of “.2”. The “1” in “1.2” represents the liquid ethanol. What is the “.2” then? It’s the rabbit feces – the byproduct. So you have no ethanol for your car, because the liquid “1” needs to be used to make more ethanol. That leaves you with just the “.2” --- a bucket of byproduct to feed your horse – you do have a horse, don’t you? If horses are like cattle, then you can only use your byproduct for one-fifth of his diet, so you’ll need four supplemental buckets of hay from your back yard to feed him. No doubt the byproduct could be used to make other things, but that would take energy.
Byproduct could be burned, but it takes a significant amount of energy to dry it out, and requires additional handling and equipment. More money can be made selling it wet to the cattle industry, which is hurting from the high price of corn. Byproduct should be put back into the ground to improve soil nutrition and structure for future generations, not sold for short-term profit and fed to cattle who aren’t biologically adapted to eating corn.
The boundaries of what is included in EROEI
calculations are kept as narrow as possible to reach positive results.
Researchers who find a positive EROEI for ethanol have not accounted for all of the energy inputs. For example, Shapouri admits the "energy used in the production of … farm machinery and equipment…, and cement, steel, and stainless steel used in the construction of ethanol plants, are not included". (Shapouri 2002). Or they assign overstated values of ethanol yield from corn (Patzek Dec 2006). Many, many, other inputs are left out.
Patzek and Pimentel have compelling evidence showing that about 30 percent more fossil energy is required to produce a gallon of ethanol than you get from it. Their papers are published in peer-reviewed journals where their data and methods are public, unlike many of the positive net energy results.
Infrastructure. Current EROEI figures don’t take into account the delivery infrastructure that needs to be built. There are 850 million combustion engines in the world today. Just to replace half the 245 million cars and light trucks in the United States with E85 vehicles will take 12-15 years, It would take over $544 million dollars of delivery ethanol infrastructure (Reynolds 2002 case B1) and $5 to $34 billion to revamp 170,000 gas stations nationwide (Heinson 2007).
The EROEI of oil when we built most of the infrastructure in this country was about 100:1, and it’s about 25:1 worldwide now. Even if you believe ethanol has a positive EROEI, you’d probably need at least an EROEI of at least 5 to maintain modern civilization (Hall 2003). A civilization based on ethanol’s “.2” rabbit poop would only work for coprophagous rabbits.
Of the four articles that showed a positive net energy for ethanol in Farrells 2006 Science article, three were not peer-reviewed. The only positive peer-reviewed article (Dias De Oliveira, 2005) states “The use of ethanol as a substitute for gasoline proved to be neither a sustainable nor an environmentally friendly option” and the “environmental impacts outweigh its benefits”. Dias De Oliveria concluded there’d be a tremendous loss of biodiversity, and if all vehicles ran on E85 and their numbers grew by 4% per year, by 2048, the entire country, except for cities, would be covered with corn.
Part 3. Biofuel is a Grim Reaper.
The energy to remediate environmental
damage is left out of EROEI calculations.
Global Warming
Soils contain 3.3 times the
amount of carbon found in the atmosphere, and 4.5 times more carbon than is
stored in all the Earth’s vegetation (Lal 2004).
If we want to reduce global warming, storing carbon in the soil will be essential. But that will be hard to pull off, because Climate change could increase soil loss by 33% to 274%, depending on the region (O'Neal 2005).
Worse yet, we keep building suburbia and shopping malls on top of crop land.
Population in the
United States could reach over one billion people by 2100 (U.S. Census
Bureau 2000), so what will happen is that we'll need more crop land and have to
cut down bottomland forests and fill in wetlands to grow food, which will
reduce stored carbon and biodiversity even further.
Intensive agriculture has already removed 20 to 50% of
the original soil carbon, and some
areas have lost 70%. To maintain soil C levels, no crop residues at all could
be harvested under many tillage systems or on highly erodible lands, and none
to a small percent on no-till, depending on crop production levels (Johnson
2006).
Deforestation of temperate
hardwood forests, and conversion of range and wetlands to grow energy and food
crops increases global warming. An
average of 2.6 million acres of crop land were paved over or developed every
year between 1982 and 2002 in the
Rainforest
destruction is increasing global
warming. Energy farming is
playing a huge role in deforestion, reducing biodiversity, water and water
quality, and increasing soil erosion. Fires to clear land for palm oil
plantations are destroying one of the last great remaining rainforests in
Biofuel from coal-burning biomass factories increases global warming (Farrell 2006). Driving a mile on ethanol from a coal-using biorefinery releases more CO2 than a mile on gasoline (Ward 2007). Coal in ethanol production is seen as a way to displace petroleum (Farrell 2006, Yacobucci 2006) and it’s already happening (Clayton 2006).
Current and future quantities of
biofuels are too minuscule to affect global warming (ScienceDaily 2007).
Surface Albedo. “How much the sun warms our climate depends on how
much sunlight the land reflects (cooling us), versus how much it absorbs
(heating us). A plausible 2% increase in the absorbed sunlight on a switch
grass plantation could negate the climatic cooling benefit of the ethanol
produced on it. We need to figure out now, not later, the full range of
climatic consequences of growing cellulose crops” (Harte 2007).
Soil Erosion
There’s an ethanol
gold rush going on. More than half
the best farmland in the
Notice that these mostly investor-owned corn and soybean
growing states, are mainly red in the map below. Red represents the areas where farms have the
highest erosion rates.
Corn and soy crops have higher erosion rates than most crops. Storms and wind wash agrichemicals (sometimes highly toxic ones that haven’t had a chance to break down) and eroded soil into the air and water. Sediment fills up reservoirs, shortening their life-span and the time dams can store water and generate electricity. Yet the energy of the hydropower lost to siltation, energy to remediate flood damage, energy to dredge dams, agricultural drainage ditches, harbors, and navigation channels, aren’t considered in EROEI calculations.
Owners seeking short-term profits have far less incentive than farmers who work their land to preserve soil and water. They don’t adopt as long-term conservation measures as farm owner-operators do (ERS 1999).

http://www.ers.usda.gov/Briefing/ConservationAndEnvironment/Gallery/sediment.htm
The dark green areas of this map represent where the highest
crop subsidy payments go and where the highest nitrogen runoff rates are. Notice
that again, these areas correspond with
investor-owned farmland. Commodity
payments were meant to be a safety net, but the money ends up being used to buy
and apply excess fertilizer, which gets into rivers, lakes, and oceans (Redlin
2007).
Farm runoff of nitrogen fertilizers has contributed to the pollution
and hypoxia (low oxygen) of rivers and lakes across the country and the 8,000
square mile dead zone in the
Climate change also appears to be increasing runoff and
erosion (SWCS 2003).

http://www.iwla.org/publications/agriculture/Farm_Bill_2007_WEB.pdf
Water Pollution
Soil erosion is a serious source of water pollution, since it causes runoff of sediments, nutrients, salts, eutrophication, and chemicals that have had no chance to decompose into streams. This increases water treatment costs, increases health costs, kills fish with insecticides that work their way up the food chain (Troeh 2005).
Ethanol plants pollute water. They generate 13 liters of wastewater for every liter of ethanol produced (Pimentel March 2005)
Water depletion
Biofuel factories use a huge amount of water – four gallons for
every gallon of ethanol produced. Despite
30 inches of rain per year in
Fifty percent of Americans rely on groundwater (Glennon 2002), and in many states, this groundwater is being depleted by agriculture faster than it is being recharged. This is already threatening current food supplies (Giampetro 1997). In some western irrigated corn acreage, groundwater is being mined at a rate 25% faster than the natural recharge of its aquifer (Pimentel 2003).
Do you want to drink,
eat, or drive?
Biodiversity
Every acre of forest and wetland converted to crop land decreases soil biota, insect, bird, reptile, and mammal biodiversity.
Part 4.
Biodiesel: Can we eat enough French Fries?
The idea we could
run our economy on discarded fried food grease is very amusing. For starters, you’d need to feed 7 million
heavy diesel trucks getting less than 8 mpg. Seems like we're all going to need
to eat a lot more French Fries, but if anyone can pull it off, it would be
Americans. Spin it as a patriotic duty and you'd see people out the door before
the TV ad finished, the most popular government edict ever.
Scale. Where’s the
Soy? Biodiesel is not ready for prime time.
Although John Deere is working on fuel additives and technologies to
burn more than 5% accredited biodiesel (made
to ASTM D6751 specifications – vegetable oil does not qualify), that is a long way off. 52 billion gallons of diesel fuel are consumed a year in the
But not to worry, a
lot is being grown in
Biodiesel shortens engine life. Currently, biodiesel concentrations higher than 5 percent can cause “water in the fuel due to storage problems, foreign material plugging filters…, fuel system seal and gasket failure, fuel gelling in cold weather, crankcase dilution, injection pump failure due to water ingestion, power loss, and, in some instances, can be detrimental to long engine life” (Borgman 2007). Biodiesel also has a short shelf life and it’s hard to store – it easily absorbs moisture (water is a bane to combustion engines), oxidizes, and gets contaminated with microbes. It increases engine NOx emissions (ozone) and has thermal degradation at high temperatures (John Deere 2006).
On the cusp of energy descent, we can’t even run the most vital aspect of our economy, agricultural machines, on “renewable” fuels. John Deere tractors can run on no more than 5% accredited biodiesel (Borgman 2007). Perhaps this is unintentionally wise – biofuels have yet to be proven viable, and mechanization may not be a great strategy in a world of declining energy.
Part 5. If we can’t drink and drive, then burn baby
burn.
Energy Crop Combustion.
Wood is a crop, subject to the same issues as corn, and
takes a lot longer to grow. Burning wood
in your stove at home delivers far more energy than the logs would if converted
to biofuels (Pimentel 2005). Wood was scarce
in
Combustion pollution is expensive to control. Some biomass has absorbed heavy metals and other pollutants from sources like coal power plants, industry, and treated wood. Combustion can release chlorinated dioxins, benzofurans, polycyclic aromatic hydrocarbons, cadmium, mercury, arsenic, lead, nickel, and zinc.
Combustion contributes to global warming by adding nitrogen oxides and the carbon stored in plants back into the atmosphere, as well as removes agriculturally essential nitrogen and phosphate (Reijnders 2006)
EROEI in doubt. Combustion plants need to produce, transport, prepare, dry, burn, and control toxic emissions. Collection is energy intensive, requiring some combination of bunchers, skidders, whole-tree choppers, or tub grinders, and then hauling it to the biomass plant. There, the feedstock is chopped into similar sizes and placed on a conveyor belt to be fed to the plant. If biomass is co-fired with coal, it needs to be reduced to ¼ inch or less, and the resulting fly ash may not be marketable to the concrete industry (Bain 2003). Any alkali or chlorine released in combustion gets deposited on the equipment, reducing overall plant efficiencies, as well as accelerating corrosion and erosion of plant components, requiring high replacement and maintenance energy.
Processing materials with different physical properties is energy intensive, requiring sorting, handling, drying, and chopping. It’s hard to optimize the pyrolysis, gasification, and combustion processes if different combustible fuels are used. Urban waste requires a lot of sorting, since it often has material that must be removed, such as rocks, concrete and metal. The material that can be burned must also be sorted, since it varies from yard trimmings with high moisture content to chemically treated wood.
Biomass combustion competes with other industries that want this material for construction, mulch, compost, paper, and other profitable ventures, often driving the price of wood higher than a wood-burning biomass plant can afford. Much of the forest wood that could be burned is inaccessible due to a lack of roads.
Efficiency is lowered if material with a high water content is burned, like fresh wood. Different physical and chemical characteristics in fuel can lead to control problems (Badger 2002). When wet fuel is burned, so much energy goes into vaporizing the water that very little energy emerges as heat, and drying takes time and energy.
Material is limited
and expensive.
Part 6. The problems with Cellulosic Ethanol could
drive you to drink.
Many plants want
animals to eat their seed and fruit to disperse them. Some seeds only germinate after going through
an animal gut and coming out in ready-made fertilizer. Seeds and fruits are easy to digest compared
to the rest of the plant, that's why all of the commercial ethanol and
biodiesel are made from the yummy parts of plants, the grain, rather than
the stalks, leaves, and roots.
But plants don’t
want to be entirely devoured.
They’ve spent hundreds of millions of years perfecting structures that
can’t easily be eaten. Be thankful
plants figured this out, or everything would be mown down to bedrock.
If we ever did figure out how to break down cellulose in our
back yard stills, it wouldn't be long before the 6.5 billion people on the
planet destroyed the grasslands and forests of the world to power generators
and motorbikes (Huber 2006)
Don Augenstein and
John Benemann, who’ve been researching biofuels for over 30 years, are skeptical
as well. According to them, “…severe barriers remain to ethanol from
lignocellulose. The barriers look as daunting as they did 30 years ago”.
Benemann says the EROEI
can be easily determined to be about five times as much energy required to make
cellulosic ethanol than the energy contained in the ethanol.
The success of cellulosic ethanol depends on finding or
engineering organisms that can tolerate extremely high concentrations of
ethanol. Augenstein argues that this
creature would already exist if it were possible. Organisms have had a billion
years of optimization through evolution to develop a tolerance to high ethanol
levels (Benemann 2006). Someone making
beer, wine, or moonshine would have already discovered this creature if it could
exist.
The range of chemical and physical properties in biomass,
even just corn stover (Ruth 2003, Sluiter
2000), is a challenge. It’s hard to make cellulosic ethanol plants optimally
efficient, because processes can’t be tuned to such wide feedstock variation..
Where will the Billion Tons of Biomass for Cellulosic Fuels
Come From?
The government
believes there is a billion tons of biomass “waste” to make cellulosic biofuels,
chemicals, and generate electricity with.
The
There isn’t enough biomass to replace 30% of our
petroleum use. The potential biomass energy is miniscule
compared to the fossil fuel energy we consume every year, about 105 exa joules
(EJ) in the
Over 25% of the “waste” biomass is expected to come from 280
million tons of corn stover. Stover
is what’s left after the corn grain is harvested. Another 120 million tons will come from soy
and cereal straw (DOE Feedstock Roadmap, DOE Biomass Plan).
There isn’t enough no-till corn stover to harvest. The success of biofuels depends on corn
residues. About 80% of farmers disk corn
stover into the land after harvest. That renders it useless -- the crop residue
is buried in mud and decomposing rapidly.
Only the 20 percent
of farmers who farm no-till will have stover to sell. The DOE Billion Ton vision assumes all farmers are no-till, 75% of
residues will be harvested, and fantasy corn and wheat yields 50% higher
than now are reached (DOE Billion Ton Vision 2005). But none of this corn stover should be
harvested because corn loses more soil than any other crop grown (Pimentel
2007).
Many tons will never be available because farmers won’t
sell any, or much of their residue (certainly not 75%).
Many more tons will be lost due to drought, rain, or loss
in storage.
Only half a percent
of a plant can be harvested sustainably every year. Plants only fix a tiny part of solar
energy into plant matter annually -- about one-tenth to one-half of one percent
new growth in temperate climates.
To prevent erosion, you could only harvest 51 million
tons of corn and wheat residues, not 400 million tons (Nelson, 2002). Other factors, like soil structure, soil
compression, water depletion, and environmental damage weren’t considered. Fifty
one million tons of residue could make about 3.8 billion gallons of ethanol, less
than 1% of our energy needs.
Using corn stover is a
problem, because corn, soy, and other row crops cause 50 times more soil
erosion than sod crops (Sullivan
2004) or more (Al-Kaisi 2000), and corn also uses more water,
insecticides and fertilizers than most crops (Pimentel 2003).
The amount of soy and cereal straw (wheat, oats, etc) is
insignificant. It would be best to use cereal grain straw,
because grains use far less water and cause far less erosion than row crops
like corn and soybeans. But that isn’t
going to happen, because the green revolution fed billions more people by
shortening grain height so that plant energy went into the edible seed, leaving
little straw for biofuels. Often 90% of soybean and cereal straw is grown no-till, but the amount of cereal straw is
insignificant and the soybean residues must remain on the field to prevent
erosion
Energy Crops
Energy crops are
grown specifically for their fuel value.
Tall perennial grasses such as switchgrass and miscanthus are being
proposed as potential energy crops.
Although grasses cause less erosion and need less fertilizer, they still
suffer from the problems that all plants have:
Poor, erodible land. There aren’t enough acres of land to grow significant amounts of energy
crops. Potential energy crop land is
usually poor quality or highly erodible land that shouldn’t be harvested. Farmers are often paid not to farm this
unproductive land. Many acres in
switchgrass are being used for wildlife and recreation.
Few suitable bio-factory sites. Biorefineries can’t be built just anywhere – very few sites could be
found to build switchgrass plants in all of
No energy crop farmers or investors. Farmers won’t grow switchgrass until
there’s a switchgrass plant. Machines to harvest and transport switchgrass
efficiently don’t exist yet (Barrionuevo 2006). The capital to build
switchgrass plants won’t materialize until there are switchgrass farmers. Since “ethanol production using switchgrass
required 50% more fossil energy than the ethanol fuel produced” (Pimentel 2005),
investors for these plants will be hard to find.
Energy crops are subject to Liebig’s law of the minimum too. Switchgrass may grow on marginal land, but it hasn’t escaped the need for minerals and water. Studies have shown the more rainfall, the more switchgrass you get, and if you remove switchgrass, you’re going to need to fertilize the land to replace the lost biomass, or you’ll get continually lower yields of switchgrass every time you harvest the crop (Vogel 2002).
Bioinvasive Potential.
These fast-growing disease-resistant plants are potentially bioinvasive,
another kudzu. Bioinvasion costs our country billions of
dollars a year (Bright, 1998). Johnson
grass was introduced as a forage grass and it’s now an invasive weed in many
states. Another fast-growing grass,
Miscanthus, from
Sugar cane: too
little to import.
Sugar Cane: can’t
grow it here. Although we grow some sugar cane despite tremendous
environmental damage (WWF) in
Sugar cane has been touted as an “all you need is sunshine” plant. But according to the FAO, the nitrogen, phosphate, and potassium requirements of sugar cane are roughly similar to maize (FAO 2004).
Wood ethanol is an
energy sink. Ethanol production
using wood biomass required 57% more fossil energy than the ethanol fuel
produced (Pimentel 2005).
Wood is a nonrenewable resource. Old-growth forests had very dense wood, with a high energy content, but wood from fast-growing plantations is so low-density and low calorie it’s not even good to burn in a fireplace. These plantations require energy to plant, fertilize, weed, thin, cut, and deliver. The trees are finally available for use after 20 to 90 years – too long for them to be considered a renewable fuel (Odum 1996). Nor do secondary forests always come back with the vigor of the preceding forest due to soil erosion, soil nutrition depletion, and mycorrhizae destruction (Luoma 1999).
There’s not enough
wood to fuel a civilization of 300 million people. Over half of
Energy crop limits.
Energy crops may not be sustainable due to water, fertilizer, and harvesting
impacts on the soil (DOE Biomass Roadmap 2005). Like all other monoculture crops, ultimately yields of energy crops will
be reduced due to “pest problems, diseases, and soil degradation” (Giampetro,
1997).
Energy crop monoculture. The “physical and chemical characteristics of feedstocks vary by source, by year, and by season, increasing processing costs” (DOE Feedstock Roadmap). That will encourage the development of genetically engineered biomass to minimize variation. Harvesting economies of scale will mean these crops will be grown in monoculture, just as food crops are. That’s the wrong direction – to farm with less energy there’ll need to be a return to rotation of diverse crops, and composted residues for soil nutrition, pest, and disease resistance.
A way around this would be to spend more on researching how
cellulose digesting microbes tackle different herbaceous and woody
biomass. The ideal energy crop would be
a perennial, tall-grass prairie / herbivore ecosystem (Tilman 2006). Tilman recommends harvesting “all grassland
in the
Farmers aren’t Stupid: They won’t sell their residues
Farmers are some of the smartest people on
earth or they’d soon go out of business.
They have to know everything from soil science to commodity
futures.
Crop production is reduced when residues are removed from
the soil. Why would farmers want to sell
their residues?
Erosion,
water, compression, nutrition. Harvesting
of stover on the scale needed to fuel a cellulosic industry won’t happen
because farmers aren’t stupid, especially the ones who work their own land. Although there is a wide range of opinion
about the amount of residue that can be harvested safely without causing
erosion, loss of soil nutrition, and soil structure, many farmers will want to be
on the safe side, and stick with the studies showing that 20% (Nelson, 2002) to
30% (McAloon et al., 2000; Sheehan, 2003) at most can be harvested, not
the 75% agribusiness claims is possible.
Farmers also care about water quality (Lal 1998, Mann et al, 2002). And farmers will decide that permanent soil
compression is not worth any price (Wilhelm 2004). As prices of fertilizer inexorably rise due to
natural gas depletion, it will be cheaper to return residues to the soil than
to buy fertilizer.
Residues are a headache. The further the farmer is from
the biorefinery or railroad, the slimmer the profit, and the less likely a
farmer will want the extra headache and cost of hiring and scheduling many
different harvesting, collection, baling, and transportation contractors for
corn stover.
Residues are used by other industries. Farm managers working for distant owners
are more likely to sell crop residues since they’re paid to generate profits,
not preserve land. But even they will
sell to the highest bidder, which might be the livestock or dairy industries, furfural
factories, hydromulching companies, biocomposite manufacturers, pulp mills, or
city dwellers faced with skyrocketing utility bills, since the high heating
value of residue has twice the energy of the converted ethanol.
Investors
aren’t stupid either. If farmers can’t
supply enough crop residues to fuel the large biorefinery in their region, who
will put up the capital to build one?
Can the biomass be harvested, baled, stored, and transported
economically?
Harvesting. Sixteen ton tractors harvest corn and spit out
stover. Many of these harvesters are
contracted and will continue to collect corn
in the limited harvest time, not stover.
If tractors are still available, the land isn’t wet, snow doesn’t fall,
and the stover is dry, three additional tractor runs will mow, rake, and bale
the stover (Wilhelm 2004). This will
triple the compaction damage to the soil (Troeh 2005), create more
erosion-prone tire tracks, increase CO2 emissions, add to labor costs, and put
unwanted foreign matter into the bale (soil, rocks, baling wire, etc).
So biomass roadmaps
call for a new type of tractor or attachment to harvest both corn and stover in
one pass. But then the tractor would
need to be much larger and heavier, which could cause decades-long or even permanent
soil compaction. Farmers worry that
mixing corn and stover might harm the quality of the grain. And on the cusp of energy descent, is it a
good idea to build an even larger and more complex machine?
If the stover is
harvested, the soil is now vulnerable to erosion if it rains, because there’s
no vegetation to protect the soil from the impact of falling raindrops. Rain also compacts the surface of the soil so
that less water can enter, forcing more to run off, increasing erosion. Water landing
on dense vegetation soaks into the soil, increasing plant growth and recharging
underground aquifers. The more stover
left on the land, the better.
Baling. The
current technology to harvest residues is to put them into bales of hay. Hay is
a dangerous commodity -- it can spontaneously combust, and once on fire, can’t
be extinguished, leading to fire loss and increased fire insurance costs. Somehow the bales have to be kept from
combusting during the several months it takes to dry them from 50 to 15 percent
moisture. A large, well drained, covered
area is needed to vent fumes and dissipate heat. If the bales get wet they will
compost (Atchison 2004).
Baling was developed
for hay and has been adapted to corn stover with limited success. Biorefineries need at least half a million
tons of biomass on hand to smooth supply bumps, much greater than any bale
system has been designed for.
Pelletization is not an option, it’s too expensive. Other options need to be found. (DOE
Feedstock Roadmap)
To get around the
problems of exploding hay bales, wet stover could be collected. The moisture
content needs to be around 60 percent, which means a lot of water will be
transported, adding significantly to the delivery cost.
Storage.
Stover needs to be stored with a moisture content of 15% or less, but it’s
typically 35-50%, and rain or snow during harvest will raise these levels even
higher (DOE Feedstock Roadmap). If it’s
harvested wet anyhow, there’ll be high or complete losses of biomass in storage
(Atchison 2004).
After catastrophic
fires, the pulp industry learned to only use wet feedstock. If residues are stored wet, as in ensilage, a
great deal of R&D will be needed to see if there are disease, pest,
emission, runoff, groundwater contamination, dust, mold, or odor control
problems. The amount of water required
is unknown. The transit time must be short, or aerobic microbial activity will
damage it. At the storage site, the wet
biomass must be immediately washed, shredded, and transported to a drainage pad
under a roof for storage, instead of baled when drier and left at the
farm. The wet residues are heavy, making
transportation costlier than for dry residues, perhaps uneconomical. It can
freeze in the winter making it hard to handle.
If the moisture is too low, air gets in, making aerobic fermentation
possible, resulting in molds and spoilage.
Transportation.
Although a 6,000 dry ton per day biorefinery would have 33% lower costs than a
2,000 ton factory, the price of gas and diesel limits the distance the biofuel
refinery can be from farms, since the bales are large in volume but low in
density, which limits how many bales can be loaded onto a truck and transported
economically.
So the “economy of
scale” achieved by a very large refinery has to be reduced to a 2,000 dry ton
per day biorefinery. Even this smaller
refinery would require 200 trucks per hour delivering biomass during harvest
season (7 x 24), or 100 trucks per day if satellite sites for storage are used. This plant would need 90% of the no-till
crop residues from the surrounding 7,000 square miles with half the
farmers participating. Yet less than 20% of farmers practice
no-till corn and not all of the farmland is planted in corn. When this
biomass is delivered to the biorefinery, it will take up at least 100 acres of
land stacked 25 feet high.
The average stover
haul to the biorefinery would be 43 miles one way if these rosy assumptions all
came true (Perlack 2002). If less than 30%
of the stover is available, the average one-way trip becomes 100 miles and the
biorefinery is economically impossible.
There is also a
shortage of truck drivers, the rail system can’t handle any new capacity, and trains
are designed to operate between hubs, not intermodally (truck to train to
truck). The existing transportation system has not changed much in 30 years,
yet this congested, inadequate infrastructure somehow has to be used to
transport huge amounts of ethanol, biomass, and byproducts (Haney 2006).
In Summary: Plants are Hard to Make into Fuels
As a systems architect and engineer, I looked at projects from start to end, trying to identify the failure points.
The Department of Energy Biomass Roadmaps and the Energy Biosciences Institute Proposal have taken a similar approach and identified the barriers to cellulosic fuels.
In business you’re limited by money, in science, you’re limited by the laws of physics and thermodynamics.
When it comes to biofuels, you’re also limited by ecosystems. To grow plants sustainably, the soil ecosystem and water supply need to be taken into account.
All of the steps from
A to Z must succeed or a project fails.
Just solving the cellulosic issues within the biorefinery won’t do any
good if the other steps fail. There are
major challenges in harvesting, storing, transporting biomass, and delivering
cellulosic fuels to customers as well.
Cellulosic
Biorefineries (see Appendix for more barriers)
There are over 60 barriers to be overcome in making cellulosic
ethanol in Section III of the DOE “Roadmap for Agriculture Biomass Feedstock
Supply in the
“Enzyme Biochemistry. Enzymes that exhibit high thermostability and substantial resistance to sugar end-product inhibition will be essential to fully realize enzyme-based sugar platform technology. The ability to develop such enzymes and consequently very low cost enzymatic hydrolysis technology requires increasing our understanding of the fundamental mechanisms underlying the biochemistry of enzymatic cellulose hydrolysis, including the impact of biomass structure on enzymatic cellulose decrystallization. Additional efforts aimed at understanding the role of cellulases and their interaction not only with cellulose but also the process environment is needed to affect further reductions in cellulase cost through improved production”.
No wonder many of the issues with cellulosic ethanol aren’t
discussed – there’s no way to express the problems in a sound bite.
It may not be possible to reduce the complex cellulose
digesting strategies of bacteria and fungi into microorganisms or enzymes that
can convert cellulose into ethanol in giant steel vats, especially given the
huge physical and chemical variations in feedstock. The field of metagenomics
is trying to create a chimera from snips of genetic material of
cellulose-digesting bacteria and fungi.
That would be the ultimate Swiss Army-knife microbe, able to convert
cellulose to sugar and then sugar to ethanol.
There’s also research to replicate termite gut cellulose breakdown. Termites depend on fascinating creatures called protists in their guts to digest wood. The protists in turn outsource the work to multiple kinds of bacteria living inside of them. This is done with energy (ATP) and architecture (membranes) in a system that evolved over millions of years. If the termite could fire the protists and work directly with the bacteria, that probably would have happened 50 million years ago. This process involves many kinds of bacteria, waste products, and other complexities that may not be reducible to an enzyme or a bacteria.
Jay Keasling, Director
of Physical Biosciences at LBNL, proposes to do the above in a synthetic
biology factory. You’d order up the
biological bits you need to create a microbial machine the way electronics
parts are obtained at Fry’s electronics stores. At U.C. Berkeley on
Biologists roll
their eyes when reductionist physicists pat them on the head and tell little
ol’ biology not to worry, living organisms can be reduced to atoms and enzymes,
just take a piece of algae here, a bit
of fungi or bacteria there and voila – a new creature that produces vast
volumes of biofuels quickly. But biology is a messy wonderment. Creatures
exist within food webs and don’t reproduce well if surrounded by their own
toxic wastes. The research is well worth
doing, but public policy shouldn’t assume synthetic biology is a “slam dunk”.
But meanwhile we’re
stuck with corn and ethanol, which in the end must be delivered to the
customer. Since ethanol can’t be delivered cheaply through pipelines, but must
be transported by truck, rail, or barge (Yacobucci 2003), this is very
expensive for the coastal regions.
The whole cellulosic ethanol enterprise falls apart if the energy returned is less than the energy invested or even one of the major stumbling blocks can't be overcome. If there isn’t enough biomass, if the residues can’t be stored without exploding or composting, if the oil to transport low-density residues to biorefineries or deliver the final product is too great, if no cheap enzymes or microbes are found to break down lignocellulose in wildly varying feedstocks, if the energy to clean up toxic byproducts is too expensive, or if organisms capable of tolerating high ethanol concentrations aren’t found, if the barriers in Appendix A can’t be overcome, then cellulosic fuels are not going to happen.
If the obstacles can be overcome, but we lose topsoil, deplete aquifers, poison the land, air, and water, what kind of Pyrrhic victory is that?
Scientists have been trying to solve these issues for over
thirty years now.
Nevertheless, this is
worthy of research money, but not public funds for commercial refineries until the
issues above have been solved. This
is the best hope we have for replacing the half million products made from and
with fossil fuels, and for liquid transportation fuels when population falls to
pre-coal levels.
Part 7.
Where do we go from here?
Subsidies and
Politics: Now, and for the Foreseeable Future, Ethanol Will Only be Made from
Corn
Biofuels from biodiverse, tall grass prairie are far
preferable to ethanol from corn and soy, but there are no commercial level
cellulosic biorefineries - and we are a long way from being able to deliver
cellulosic fuels to customers. Even if
all of the barriers to cellulosic fuels could be achieved before oil shocks
hit, they’d bankrupt our soils so quickly that there’d be no biomass to feed
the maws of the biorefineries.
How come there are over 116 ethanol plants with 79 under construction and 200 more planned? Government subsidies and tax breaks.
Federal and state ethanol subsidies add up to 79 cents per liter (McCain 2003), with most of that going to agribusiness, not farmers. There is also a tax break of 5.3 cents per gallon for ethanol (Wall Street Journal 2002). An additional 51 cents per gallon goes mainly to the oil industry to get them to blend ethanol with gasoline.
In addition to the $8.4 billion per year subsidies for corn and ethanol production, the consumer pays an additional amount for any product with corn in it (Pollan 20005), beef, milk, and eggs, because corn diverted to ethanol raises the price of corn for the livestock industry.
California Senator Feinstein calls ethanol a transfer of
wealth to the
Coming to a theater near you: Enron Part 2.
The subsidies may never end, because
“Once we have a corn-based technology up and running the political system will protect it,” said Lawrence J. Goldstein, a board member at the Energy Policy Research Foundation. “We cannot afford to have 15 billion gallons of corn-based ethanol in 2015, and that’s exactly where we are headed” (Barrionuevo 2007).
Let’s stop the ethanol subsidies and see if this elephant can fly on its own.
Conclusion
President Carter asked us to put our sweaters on, and had
plans for a soft landing, but Americans chose Reagans' "Morning in
Soil is the bedrock of civilization (Perlin 1991, Ponting 1993). Biofuels are not sustainable or renewable. Why would we destroy our topsoil, increase global warming, deplete and pollute groundwater, destroy fisheries, and use more energy than what’s gained to make ethanol? Why would we do this to our children and grandchildren?
Perhaps it’s a combination of pork barrel politics, an
uninformed public, short-sighted greedy agribusiness corporations, jobs for the
But this madness
puts our national security at risk.
Destruction of topsoil and collateral damage to water, fisheries, and
food production will result in less food to eat or sell for petroleum and
natural gas imports. Diversion of
precious dwindling energy and money to impossible solutions is a threat to our
nations’ future. In an oil-less future, prime farm land is a
nation’s number one resource.
We are upset at
mountain tops being blasted off to produce coal, and the damage done by mining
for metal, yet mining footprints pale in comparison with the hundreds of millions
of acres being mined to grow food.
Regardless of the energy crisis, agriculture needs reforming.
Let's use the limited energy we have left to fix what's
wrong with agriculture.
Fix the unsustainable
and destructive aspects of industrial agriculture. At least some good would
come out of the ethanol fiasco if more attention were paid to how we grow our
food. The effects of soil erosion on crop production have been hidden by
mechanization and intensive use of fossil fuel fertilizers and chemicals on crops
bred to tolerate them. As energy
declines, crop yields will decline as well.
States can play an
important role.
Jobs. Since part of what’s driving the ethanol
insanity is job creation, divert the subsidies and pork barrel money to erosion
control and sustainable agriculture.
Maybe
Continue to fund cellulosic ethanol research, focusing on how to make 500,000 fossil-fuel-based products (i.e. medicine, chemicals, plastics, etc) and fuel for when population declines to pre-fossil fuel carrying capacity. The feedstock should be from a perennial, tall-grass prairie herbivore ecosystem, not food crops. But don’t waste taxpayer money to build demonstration or commercial plants until most of the research and sustainability barriers have been solved.
Take away the E85
loophole that allows
There are better, easier ways to stretch out petroleum than adding ethanol to it. Just keeping tires inflated properly would save more energy than all the ethanol produced today. Reducing the maximum speed limit to 55, consumer driving tips, truck stop electrification, and many other measures can save far more fuel in a shorter time than biofuels ever will, far less destructively. Better yet, Americans can bike or walk, which will save energy used in the health care system.
Reform our
non-sustainable agricultural system
There are many institutions and people who have been working on these issues for decades. What we need is a grass roots movement to enact reforms while we still have plentiful energy.
It’s not unreasonable to expect farmers to conserve the soil, since the fate of civilization lies in their hands. But we need to pay farmers for far more than the cost of growing food so they can afford to conserve the land. In an oil-less future, healthy topsoil will be our most important resource.
If we do nothing,
dustbowls will return. Erosion and
other ecological damage is insidious, it doesn't happen overnight. We should
try to manage our soils to last at least two thousand years. There's no excuse
not to - we know how to do this.
Responsible politicians need to tell Americans why their love affair with the car can’t continue. Leaders need to make the public understand that there are limits to growth, and an increasing population leads to the “Tragedy of the Commons”. Even if it means they won’t be re-elected. Arguing this amidst the church of development that prevails is like walking into a Bible-belt church and telling the congregation God doesn’t exist, but it must be done.
We are betting the farm on making cellulosic fuels work at a time when our energy and financial resources are diminishing. No matter how desperately we want to believe that human ingenuity will invent liquid or combustible fuels despite the laws of thermodynamics and how ecological systems actually work, the possibility of failure needs to be contemplated.
Living in the moment might be enlightenment for individuals, but for a nation, it’s disastrous. Is there a Plan B if biofuels don’t work? Coal is not an option. CO2 levels over 1,000 ppm could lead to the extinction of 95% of life on the planet (Lynas 2007, Ward 2006, Benton 2003).
Here we are, on the cusp of energy descent, with mechanized petrochemical farms. We import more farm products now than we sell abroad (Rohter 2004). Suburban sprawl destroys millions of acres of prime farm land as population grows every year. We’ve gone from 7 million family farms to 2 million much larger farms and destroyed a deeply satisfying rural way of life.
More people will need to go back to the land during energy
descent, so let's start now, and encourage small family farms.
There need to be
plans for de-mechanization of the farm economy if liquid fuels aren’t found.
There are less than four million horses,
donkeys, and mules in
We need to start on "Plan B" now in case biofuels
aren't invented before oil shocks strike.
We don't want to experience the same discontinuities as
The population of the
If we wait, the consequences will be Stalinesque. You can’t just do this overnight, and with the ownership of land concentrated in so few hands, you’re automatically heading towards feudalism rather than the Jeffersonian ideal our nation was founded on.
We need to transition from petroleum power to muscle power gracefully if we want to preserve democracy. Paul Roberts wonders whether the coming change will be "peaceful and orderly or chaotic and violent because we waited too long to begin planning for it" (Roberts 2004).
We're facing Peak
Oil, Peak Natural Gas, Peak Coal, and global warming. As we go down the energy ladder and go up the
thermometer, what is the likely carrying capacity of the
Do you want to eat or drive? Even without growing food for biofuels, crop production per capita is going to go down as population keeps increasing, fossil fuel energy decreases, topsoil loss continues, and aquifers deplete, especially the Ogallala (Opie 2000). Where will the money come from to buy imported oil and natural gas if we don’t have food to export?
There is no such thing as “waste” biomass. As we go down the energy ladder, plants will increasingly be needed to stabilize climate, provide food, medicine, shelter, furniture, heat, light, cooking fuel, clothing, etc.
Biofuels are a threat
to the long-term national security of our nation. Is Dr. Strangelove in charge, with a plan to
solve defense worries by creating a country that’s such a salty polluted desert,
no one would want to invade us? Why is
Dr. Strangelove spending the last bits of energy in Uncle Sam’s pocket on
moonshine? Perhaps he’s thinking that we’re
all going to need it, and the way things are going, he’s probably right.
Appendix
Department of Energy Biofuel Roadmap
Barriers
This is a partial summary of biofuel barriers from Department of Energy. Unless otherwise footnoted, the problems with biomass fuel production are from the Multi Year Program Plan DOE Biomass Plan or Roadmap for Agriculture Biomass Feedstock Supply in the United States. (DOE Biomass Plan, DOE Feedstock Roadmap).
Resource and
Sustainability Barriers
1) Biomass feedstock will ultimately be limited by finite amounts of land and water
2) Biomass production may not be sustainable because of impacts on soil compaction, erosion, carbon, and nutrition.
3) Nor is it clear that perennial energy crops are sustainable, since not enough is known about their water and fertilizer needs, harvesting impacts on the soil, etc.
4) Farmers are concerned about the long-term effects on soil, crop productivity, and the return on investment when collecting residues.
5) The effects of biomass feedstock production on water flows and water quality are unknown
6) The risks of impact on biodiversity and public lands haven’t been assessed.
Economic Barriers (or
Investors Aren’t Stupid)
1) Biomass can’t compete economically with fossil fuels in transportation, chemicals, or electrical generation.
2) There aren’t any credible data on price, location, quality and quantity of biomass.
3) Genetically-modified energy crops worry investors because they may create risks to native populations of related species and affect the value of the grain.
4) Biomass is inherently more expensive than fossil fuel refineries because
a) Biomass is of such low density that it can’t be transported over large distances economically. Yet analysis has shown that biorefineries need to be large to be economically attractive – it will be difficult to find enough biomass close to the refinery to be delivered economically.
b) Biomass feedstock amounts are unpredictable since unknown quantities will be lost to extreme weather, sold to non-biofuel businesses, rot or combust in storage, or by used by farmers to improve their soil.
c) Ethanol can’t be delivered in pipelines due to likely water contamination. Delivery by truck, barge, and rail is more expensive. Ethanol is a hazardous commodity which adds to its transportation cost and handling.
d) Biomass varies so widely in physical and chemical composition, size, shape, moisture levels, and density that it’s difficult and expensive to supply, store, and process.
e) The capital and operating costs are high to bale, stack, palletize, and transport residues
f) Biomass is more geographically dispersed, and in much more ecologically sensitive areas than fossil resources.
g) The synthesis gas produced has potentially higher levels of tars and particulates than fossil fuels.
h) Biomass plants can’t benefit from the same large-scale cost savings of oil refineries because biomass is too dispersed and of low density.
5) Consumers won’t buy ethanol because it costs more than gasoline and contains 34% less energy per gallon. Consumer reports wrote they got the lowest fuel mileage in recent years from ethanol due to its low energy content compared to gasoline, effectively making ethanol $3.99 per gallon. Worse yet, automakers are getting fuel-economy credits for every E85 burning vehicle they sell, which lowers the overall mileage of auto fleets, which increases the amount of oil used and lessens energy independence. (Consumer Reports)
Equipment and Storage
Barriers
1) There are no harvesting machines to harvest the wide range of residue from different crops, or to selectively harvest components of corn stover.
2) Current biomass harvesting and collection methods can’t handle the many millions of tons of biomass that need to be collected.
3) How to store huge amounts of dry biomass hasn’t been figured out.
4) No one knows how to store and handle vast quantities of different kinds of wet biomass. You can lose it all since it’s prone to spoiling, rotting, and spontaneous combustion
Preprocessing
Barriers
1) We don’t even know what the optimum properties of biomass to produce biofuels are, let alone have instruments to measure these unknown qualities.
2) Incoming biomass has impurities that have to be gotten out before grinding, compacting, and blending, or you may damage equipment and foul chemical and biological processes downstream.
3) Harvest season for crops can be so short that it will be difficult to find the time to harvest cellulosic biomass and pre-process and store a year of feedstock stably.
4) Cellulosic biomass needs to be pretreated so that it’s easier for enzymes to break down. Biomass has evolved for hundreds of millions of years to avoid chemical and biological degradation. How to overcome this reluctance isn’t well enough understood yet to design efficient and cost-effective pre-treatments.
5) Pretreatment reactors are made of expensive materials to resist acid and alkalis at high temperatures for long periods. Cheaper reactors or low acid/alkali biomass is needed.
6) To create value added products, ways to biologically, chemically, and mechanically split components off (fractionate) need to be figured out.
7) Corn mash needs to be thoroughly sterilized before microorganisms are added, or a bad batch may ensue. Bad batches pollute waterways if improperly disposed of. (Patzek Dec 2006).
Cellulosic Ethanol
Showstoppers
1) The enzymes used in cellulosic biomass production are too expensive.
2) An enzyme that breaks down cellulose must be found that isn’t disabled by high heat or ethanol and other end-products, and other low cost enzymes for specific tasks in other processes are needed.
3) If these enzymes are found, then cheap methods to remove the impurities generated are needed. Impurities like acids, phenols, alkalis, and salts inhibit fermentation and can poison chemical catalysts.
4) Catalysts for hydrogenation, hydrgenolysis, dehydration, upgrading pyrolysis oils, and oxidation steps are essential to succeeding in producing chemicals, materials, and transportation fuels. These catalysts must be cheap, long-lasting, work well in fouled environments, and be 90% selective.
5) Ethanol production needs major improvements in finding robust organisms that utilize all sugars efficiently in impure environments.
6) Key to making the process economic are cheap, efficient fermentation organisms that can produce chemicals and materials. Wald writes that the bacteria scientists are trying to tame come from the guts of termites, and they’re much harder to domesticate than yeast was. Nor have we yet convinced “them to multiply inside the unfamiliar confines of a 2,000-gallon stainless-steel tank” or “control their activity in the industrial-scale quantities needed” (Wald 2007).
7) Efficient aerobic fermentation organisms to lower capital fermentation costs.
8) Fermentation organisms that can make 95% pure fermentation products.
9) Cheap ways of removing impurities generated in fermentation and other steps are essential since the costs now are far too high.
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