Peak Soil: Why cellulosic ethanol, biofuels
are unsustainable and a threat to America
Written by Alice
Friedemann
Released April 10, 2007
"The nation that destroys its soil destroys itself." - President
Franklin D. Roosevelt
Peak Soil: Why Cellulosic ethanol and other Biofuels are Not
Sustainable and are a Threat to America’s National Security
Part 1. The Dirt on Dirt.
Part 2. The Poop on Ethanol: Energy Returned on Energy Invested
(EROEI)
Part 3. Biofuel is a Grim Reaper.
Part 4. Biodiesel: Can we eat enough French Fries?
Part 5. If we can’t drink and drive, then burn baby burn. - Energy
Crop Combustion
Part 6. The problems with Cellulosic Ethanol could drive you to drink.
Part 7. Where do we go from here?
Appendix
Department of Energy's Biofuel Roadmap Barriers
References
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 U.S. 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 Iraq, formerly Mesopotamia, where 75% of
the farm land became a salty desert.
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". Iowa has some
of the best topsoil in the world. In the past century, half of it’s
been lost, from an average of 18 to 10 inches deep (Pate 2004, Klee
1991). 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.
Erosion removes the most fertile parts of the soil (USDA-ARS). When you
feed the soil with fertilizer, 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 (Wardle
2004). If you dove into the soil and swam around, you’d be surrounded
by miles of thin strands of mycorrhizal fungi that help plant roots
absorb more nutrients and water, plus millions of creatures, most of
them unknown. There’d be thousands of species in just a handful of
earth –- springtails, bacteria, and worms digging airy subways. 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
as 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:
Row crops such as corn and soy cause 50 times more soil erosion than
sod crops [e.g., hay] (Sullivan 2004) or more (Al-Kaisi 2000), because
the soil between the rows can wash or blow away. If corn is planted
with last year's corn stalks left on the ground (no-till), erosion is
less of a problem, but only about 20% of corn is grown no-till. Soy is
usually grown no-till, but insignificant residues to harvest for fuel.
Corn uses more water, insecticide, and fertilizer than most crops
(Pimentel 2003). Due to high corn prices, continuous corn (corn crop
after corn crop) is increasing, rather than rotation of nitrogen fixing
(fertilizer) and erosion control sod crops with corn.
The government has studied the effect of growing continuous corn, and
found it increases eutrophication by 189%, global warming by 71%, and
acidification by 6% (Powers 2005).
Farmers want to plant corn on highly-erodible, water protecting, or
wildlife sustaining Conservation Reserve Program land. Farmers are paid
not to grow crops on this land. But with high corn prices, farmers are
now asking the Agricultural Department to release them from these
contracts so they can plant corn on these low-producing,
environmentally sensitive lands (Tomson 2007).
Crop residues are essential for soil nutrition, water retention, and
soil carbon. Making cellulosic ethanol from corn residues -- the parts
of the plant we don’t eat (stalk, roots, and leaves) – removes water,
carbon, and nutrients (Nelson, 2002, McAloon 2000, Sheehan, 2003).
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):
"I have no idea why soil scientists aren't questioning corn and
cellulosic ethanol plans. Quite frankly I’m not sure that our society
has had any sort of reasonable debate about this with all the facts
laid out. When you see that even if all of the corn was converted to
ethanol and that would not provide more than 20% of our current liquid
fuel use, it certainly makes me wonder, even before considering the
conversion efficiency, soil loss, water contamination, food price
problems, etc."
"Biomass production is not sustainable. Only business men and women
in the refinery business believe it is."
"Should we be using our best crop land to grow gasohol and contribute
further to global warming? What will our children grow their food on?"
"As agricultural scientists, we are programmed to make farmers
profitable, and therefore profits are at the top of the list, and not
soil, family, or environmental sustainability".
"Government policy since WWII has been to encourage overproduction to
keep food prices down (people with full bellies don't revolt or object
too much). It's hard to make a living farming commodities when the
selling price is always at or below the break even point. Farmers have
had to get bigger and bigger to make ends meet since the margins keep
getting thinner and thinner. We have sacrificed our family farms in the
name of cheap food. When farmers stand to make few bucks (as with
biofuels) agricultural scientists tend to look the other way".
"You are quite correct in your concern that soil science should be
factored into decisions about biofuel production. Unfortunately, we
soil scientists have missed the boat on the importance of soil
management to the sustainability of biomass production, and the
long-term impact for soil productivity."
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" (Jackson 1980).
Natural Gas in Agriculture
When you take out more nutrients and organic matter from the soil than
you put back in, you are "mining" the topsoil. The organic matter is
especially important, since that’s what prevents erosion, improves soil
structure, health, water retention, and gives the next crop its
nutrition. Modern agriculture only addresses the nutritional component
by adding fossil-fuel based fertilizers, and because the soil is
unhealthy from a lack of organic matter, copes with insects and disease
with oil-based pesticides.
"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). This is known as the Haber-Bosch process,
and it’s a big 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).
Our national security is at risk as we 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.
Agriculture competes with homes and industry for fast depleting North
American natural gas. Natural gas price increases have already caused
over 280,000 job losses (Gerard 2006). Natural gas is also used for
heating and cooking in over half our homes, generates 15% of
electricity, and is a feedstock for thousands of products.
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. Iowa’s a big hog state, but
commercial swine operations feed pigs a maximum of 5 to 10% byproduct
(Trenkle 2006; Shurson 2003).
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 (dung-eating) 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 twice the amount of carbon found in the atmosphere, and
three times more carbon than is stored in all the Earth’s vegetation
(Jones 2006).
Climate change could increase soil loss by 33% to 274%, depending on
the region (O'Neal 2005).
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 USA (NCRS 2004). The only new
crop land is forest, range, or wetland.
Rainforest destruction is increasing global warming. Energy farming is
playing a huge role in deforestation, 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 Borneo, spewing so much carbon that Indonesia is third
behind the United States and China in releasing greenhouse gases.
Orangutans, rhinos, tigers and thousands of other species may be driven
extinct (Monbiot 2005). Borneo palm oil plantation lands have grown
2,500% since 1984 (Barta 2006). Soybeans cause even more erosion than
corn and suffer from all the same sustainability issues. The Amazon is
being destroyed by farmers growing soybeans for food (National
Geographic Jan 2007).and fuel (Olmstead 2006).
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 minisucle 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).
Eutrophication.
Farm runoff of nitrogen fertilizers has contributed to the hypoxia (low
oxygen) of rivers and lakes across the country and the dead zone in the
Gulf of Mexico. Yet the cost of the lost shrimp and fisheries and
increased cost of water treatment are not subtracted from the EROEI of
ethanol.
Soil Erosion
Corn and soybeans have higher than average erosion rates. Eroded soil
pollutes air, fills up reservoirs, and shortens 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.
The majority of the best soil in the nation is rented and has the
highest erosion rates. More than half the best farmland in the United
States is rented: 65% in Iowa, 74% in Minnesota, 84% in Illinois, and
86% in Indiana. Owners seeking short-term profits have far less
incentive than farmers who work their land to preserve soil and water.
As you can see in the map below [check with us later or use link
below], the dark areas, which represent the highest erosion rates, are
the same areas with the highest percentage of rented farmland.
http://www.ers.usda.gov/Briefing/ConservationAndEnvironment/Gallery/sediment.htm
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 Iowa,
there may not be enough water for corn ethanol factories as well as
people and industry. Drought years will make matters worse (Cruse
2006).
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).
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 United States, but
only 75 million gallons of biodiesel were produced – two-tenths of one
percent of what’s needed. To get the country to the point where
gasoline was mixed with 5 percent biodiesel would require 64 percent of
the soybean crop and 71,875 square miles of land (Borgman 2007), an
area the size of the state of Washington. Soybeans cause even more
erosion than corn.
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 America when there were just 75 million people.
Electricity from biomass combustion is not economic or sustainable.
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 in size, 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. California couldn’t use crop
residues due to low bulk density. In 2000, the viability of California
biomass enterprise was in serious doubt because the energy to produce
biomass was so
high due to the small facilities and high cost of collecting and
transporting material to the plants (Bain 2003).
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 United States lost 52 million acres of cropland between 1982 and
2002 (NCRS 2004). At that rate, all of the cropland will be gone in 140
years.
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 USA. If
you burned every living plant and its roots, you’d have 94 EJ of energy
and we could all pretend we lived on Mars. Most of this 94 EJ of
biomass is already being used for food and feed crops, and wood for
paper and homes. Sparse vegetation and the 30 EJ in root systems are
economically unavailable – leaving only a small amount of biomass
unspoken for (Patzek June 2006).
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 fantasizes corn and wheat yields 50%
higher than now are reached (DOE Billion Ton Vision 2005).
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.
Sustainable harvesting of plants is only 1/200th at best. Plants can
only fix a tiny part of solar energy into plant matter every year --
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
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 South Dakota (Wu 1998). Much of the state didn’t have enough
water or adequate drainage to build an ethanol factory. The sites had
to be on main roads, near railroad and natural gas lines, out of
floodplains, on parcels of at least 40 acres to provide storage for the
residues, have electric power, and enough biomass nearby to supply the
plant year round.
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). 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).
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, is now being proposed as a biofuel.
It’s been described as "Johnson grass on steroids" (Raghu 2006).
Sugar cane: too little to import. Brazil uses oil for 90% of their
energy, and 17 times less oil (Jordan 2006). Brazilian ethanol
production in 2003 was 3.3 billion gallons, about the same as the USA
in 2004, or 1% of
our transportation energy. Brazil uses 85% of their cane ethanol,
leaving only 15% for export.
Sugar Cane: can’t grow it here. Although we grow some sugar cane
despite tremendous environmental damage (WWF) in Florida thanks to the
sugar lobby, we’re too far north to grow a significant amount of sugar
cane or other fast growing C4 plants.
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 North America was deforested by 1900, at a time when there
were only 75 million people (Williams 2003). Most of this was from home
use. In the 18th century the average Northeastern family used 10 to 20
cords per year. At least one acre of woods is required to sustainably
harvest one cord of wood (Whitney 1994).
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).
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).
Residues could be stored wet, as they are in ensilage, but a great deal
of R&D are needed and 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).
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 United States" (DOE Feedstock Roadmap 2003). For example:
"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.
Finally, ethanol must be delivered. A motivation to develop cellulosic
ethanol is the high delivery cost of corn grain ethanol from the
Midwest to the coasts, since ethanol can’t be delivered cheaply through
pipelines, but must be transported by truck, rail, or barge (Yacobucci
2003).
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 Faustian
bargain 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
How come there are over 116 ethanol plants with 79 under construction
and 200 more planned? The answer: 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.
Worst of all, the subsidies may never end, because Iowa plays a leading
role in who’s selected to be the next president. John McCain has
softened his stand on ethanol (Birger 2006). All four senators in
California and
New York have pointed out that "ethanol subsidies are nothing but a way
to funnel money to agribusiness and corn states at the expense of the
rest of the country" (Washington Post 2002).
"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).
Conclusion
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
Midwest, politicians getting too large a percent of their campaign
money from agribusiness (Lavelle 2007), elected leaders without science
degrees, and desperation to provide liquid transportation fuels
(Bucknell 1981, Hirsch 2005).
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.
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.
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 Iowa will emerge from its makeover
looking like Provence, France, and volunteers won’t be needed to hand
out free coffee at rest areas along I-80.
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.
California should not adopt the E10 ethanol blend for global warming
bill AB 32. Biofuels are at best neutral and at worst contribute to
global warming. A better early action item would be to favor
low-emission vehicle sales and require all new cars to have energy
efficient tires.
Take away the E85 loophole that allows Detroit automakers to ignore
CAFE standards and get away with selling even more gas guzzling
vehicles (Consumer Reports 2006). Raise the CAFE standards higher
immediately.
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.
Let’s stop the subsidies and see if ethanol can fly.
Reform our non-sustainable agricultural system
Give integrated pest management and organic agriculture research more
funding
The National Resources Conservation Service (NCRS) and other
conservation agencies have done a superb job of lowering the erosion
rate since the dustbowl of the 1930’s. Give these agencies a larger
budget to further the effort.
To promote land stewardship, change taxes and zoning laws to favor
small family farms. This will make possible the "social, economic, and
environmental diversity necessary for agricultural and ecosystem
stability" (Opie 2000).
Make the land grant universities follow the directive of the Hatch
Act of 1887 to improve the lives of family farmers. Stop funding
agricultural mechanization and petrochemical research and start funding
how to
fight pests and disease with diverse crops, crop rotations, and so on
(Hightower 1978).
Don’t allow construction of homes and businesses on prime farm land.
Integrate livestock into the crop rotation.
Teach family farmers and suburban homeowners how to maximize food
production in limited space with Rodale and Biointensive techniques.
Since less than 1 percent of our elected leaders and their staff have
scientific backgrounds, educate them in systems ecology, population
ecology, soil, and climate science. So many of the important issues
that face us need scientific understanding and judgment.
Divert funding from new airports, roads, and other future senseless
infrastructure towards research in solar, wind, and cellulosic
products. We’re at the peak of scientific knowledge and our economic
system hasn’t been knocked flat yet by energy shortages – if we don’t
do the research now, it may never happen.
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.
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
this 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.
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 America today. According to Bucknell, if the farm
economy were de-mechanized, you'd need at least 31 million farm workers
and 61 million horses. (Bucknell 1981)
The population of the United States has grown over 25 percent since
Bucknell published Energy and the National Defense. To de-mechanize
now, we'd need 39 million farm workers and 76 million horses. The
horsepower represented by just farm tractors alone is equal to 400
million horses. It’s time to start increasing horse and oxen numbers,
which will leave even less biomass for biorefineries.
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).
What is the carrying capacity of the nation? Is it 100 million
(Pimentel 1991) or 250 million (Smil 2000)? Whatever carrying capacity
is decided upon, pass legislation to drastically lower immigration and
encourage one child families until America reaches this number. Or we
can let resource wars, hunger, disease, extreme weather, rising oceans,
and social chaos legislate the outcome.
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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