August 14, 2007 4:00 AM PDT

Cellulosic ethanol: A fuel for the future?

In the pine forests of rural Georgia, Devon Dartnell sees a path into the global fuel economy.

As the biomass program manager for the Georgia Forestry Commission, Dartnell is impatiently waiting for construction to begin next month of a plant that will convert forestry wastes into ethanol, a car fuel.

The facility is an important test to see whether lumber and agricultural by-products, rather than corn or sugar cane, are an economically viable "feedstock" for ethanol production. Behind the plant is Range Fuels, a start-up headed by a former Apple executive and financed by famed Silicon Valley venture capitalist Vinod Khosla.

Dartnell hopes this project, eligible for up to $76 million in U.S. Department of Energy grants, will lead to many more plants--and a new industry--in the state.

"This gives us energy security and it keeps all the money in-state," said Dartnell. "Today, if we buy a tank of gasoline, a lot of money ends up with the oil reserve owners and refiners, and it's spread all around the world."

Georgia's enthusiasm for the Range Fuels plant--one of a handful now being planned in the U.S.--underscores the high hopes attached to cellulosic ethanol, an advanced biofuel that backers anticipate will play a large role in meeting federal targets for domestic fuel production that can one day offset reliance on foreign oil.

But like many energy-related technologies now being actively pursued, there are potential pitfalls for advanced biofuels, including long-standing technology hurdles and environmental questions. And getting clear-cut answers on the benefits and trade-offs of biofuels is tricky.

"Just because the technology can be done right doesn't mean we will use it right or develop it in a smart way; that's the real challenge," said Nathanael Greene, senior policy analyst at the National Resources Defense Council (NRDC). "Biofuels, in particular, can be anywhere from very good for the environment to very bad."

Grain versus cellulose
Cellulosic ethanol promises several advantages over corn-based ethanol which, fueled by government policies and investor capital, is now undergoing a massive build-out.

Making ethanol from forestry or agricultural waste does not involve the same intensive farming as corn, which requires more water and labor, cellulosic ethanol proponents say. Also, in the ongoing food-versus-fuel debate, cellulosic ethanol advocates say that forests don't compete for land with food crops.

The Soperton, Ga., plant will be using wood cast away by loggers. Trees are hauled to a central point where their tops and branches are cut off, providing the material for Range Fuels' multi-step thermochemical process.

Tree branches will go into a large tank where enough heat and pressure are applied to the mix to turn it into a gas. That synthetic gas is treated and then passed through a chemical catalyst which converts the gas to alcohol. Finally, the alcohol gas is converted to fuels and then turned into liquid.

Companies are pursuing different routes to cellulosic ethanol. Iogen, one of several companies using enzymatic processes, has built a demonstration plant in Ottawa that uses specially designed enzymes to convert agricultural wastes, such as corn stalks and straw, to ethanol.

Other wood wastes, even wood from natural disasters and fires, could be used, Dartnell said. Researchers are also busy devising processes to convert grasses, such as switchgrass and Micanthus, into fuels.

"Everybody is looking for feedstocks which they have to then plant and grow," Dartnell said. But because current logging practices usually leave branches behind, the waste is already there. It's just not being put to good use.

Indeed, companies have promised working cellulosic ethanol processes for years, but at this point, most work remains in the research or trial stage.

Part of what has held back making advanced biofuels from wood or straw is the significantly higher capital costs it takes to build a plant. But even with the bigger up-front investment required, rising corn prices have made the cost of biofuel from cellulosic sources only slightly higher than corn-based ethanol, according to a recently published report in the journal Biofuels, Bioproducts and Biorefining.

Range claims its first plant will be completed next year and will be capable of making 20 million gallons of ethanol a year. It intends to later expand to 100 million gallons per year.

Dartnell estimates that the state has enough wood residue from tree farming and milling to create 2 billion gallons per year.

CONTINUED: A growing trend…
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Nice to see
Nice to see that some of the questions about ethanol are aired in
this article, instead of the indiscriminate cheerleading that one
often sees in articles about it.
Posted by billmosby (536 comments )
Reply Link Flag
Using farmland to run automobiles is really one of the most misguided ideas that I've ever seen. I have no problem with using by products, I would have serious doubts that such a method ever make much of a dent in gasoline usage. The only real long term solution is scrapping the internal combustion engine. Fire is pretty much the most primitive technology known to man. There has to be something better. It's really nuts that we are starting tiny little contained fires in order to propel ourselves around.
Posted by Wiz Zee (20 comments )
Reply Link Flag
Thanks! Another person who gets it.

We're just going to grow all of this corn, dumping more fertilizer into the ground and that's better for the environment somehow? Ethanol is not a long term solution.
Posted by lewissalem (167 comments )
Link Flag
Cellulosic Ethanol
I ,ike the idea of putting the waste material to use. But, is there a net energy surplus, or net loss, meaning, does it consume more energy to make the ethanol, than you get from the ethanol produced?

I think the better energy fuel of the future is in the hydrogen fuel cell technology, where the hydrogen is infinitely recyclable.
Posted by sirgak (4 comments )
Reply Link Flag
Hydrogen is not a fuel!
Hydrogen is just an energy carrier, and a poor one at that. The only way to make recyclable hydrogen is splitting water with electricity. That process is only about 70% efficient, so 30% of your energy is lost right then. Then fuel cells, while a lot more efficient than internal combustion engines, still only 50% efficient. And the output of fuel cells, electricity! So you take electricity as input, throw 65% or more of it away in order to eventually make electricity to power an electric motor. How does that make any sense at all.
And that analysis is not including what it takes to make the original electricity in the first place. The hydrogen economy would be about the worst thing from a total energy consumption stand point this country could do.
Posted by jlfelder (61 comments )
Link Flag
Net energy surplus
Cellulosic ethanol production should result in a fairly large net energy surplus, certainly MUCH better than ethanol from corn that is only just barely positive.

As for you're perpetual motion idea of hydrogen being fully recyclable, I'd recommend you go back and take a first-year thermodynamics course in college. Hopefully that will make you realize how out-to-lunch such a idea is! There ain't no such thing as a free lunch and hydrogen is DEFINITELY never going to be 'infinitely renewable'. The current process of electrolysis of water to hydrogen and then recombining hydrogen to form water again in a fuel cell is about 33% efficient with hopes to get it up to about 45% or 50% at some time in the future. What that means is that even before you move your car an inch you've already lost more than half the energy you put in.

Hydrogen fuel cells are a total greenwashing scam that are totally pointless now and will continue to be pointless until we find an extremely abundant, clean, cheap and safe source of electricity. None of the technologies known today, with the possible exception of nuclear fusion, are going to fit that bill.
Posted by Hoser McMoose (182 comments )
Link Flag
Hemp is cellulose. Use it!
Hemp (weed) is used world wide. It would make an excellent source of cellulose needing little water, fertilization, or pest control.
Posted by dahnb (49 comments )
Reply Link Flag
You go, Towlie!
(South Park character)
Posted by billmosby (536 comments )
Link Flag
A Hemp varity,of which there are many; that,has many different uses,"not all varity's are drugs."
2500,products can be made from ,not the least of which is ethenol,food,and oil,which is high in omega3 fatty acids,healthy fat, from the seed,which is also high in protien and of course, fuel from the stalks,of cellulose,which by the way,can also be used to make cloth,even soft,silk and linen like, material from.

Since,before the united states,was even a country,hemp ,was used to make sailing cloth ,clothing,rope,etc...

Thomas Jefferson,encouraged farmers ,to grow it ,because, he knew it's value as a crop ,and as a way to ensure prosparity ,for the farmers, and the rest of the country.
Posted by GIVEMELIBERTY2 (3 comments )
Link Flag
But, hasn't nature already done most of the job with coal? Not sexy enough. Change for change sake. Pull a horse trailer with a tractor. But, don't clear the forest floors for fire control. Liberal thinking is a non-sequitor.

While I'm here, Chrysler's ill fated romance with the mini-turbine needs a new look.
Posted by monte_meade (1 comment )
Reply Link Flag
Blast from the past
My college roommate's father worked for Chrysler during the
time they were experimenting with turbine cars. He got to drive
one of the 50 that were built for road testing and said you could
blow all the leaves off his front lawn with it. It would be cool to
have a turbine car, but unfortunately they are not very efficient
unless run at design conditions, which usually means full rated
power. They might work all right in a hybrid design where they
could be run most efficiently, but frequent shutdowns and
restarts don't sit well with turbines. Uses lots of fuel to start, and
the thermal cycling uses up the turbine life rapidly. Pity.
Posted by billmosby (536 comments )
Link Flag
We told you so! Milk soon to be $5 a gallon, Now a 2x4 will be $5
Simply look at the efficiency that photosynthesis can capture the energy from the sun and you will see that biofuels and ethanol are a dead end path. Direct Solar energy capture by high-grade solar cells with parabolic increased suns is the only solution to replace gas and oil. Sure the price may always be more expensive than oil but look at the big picture in Iraq and yes maybe global warming if CO2 has an effect on warming and you will see that we need a solution well before oil runs out. A Solar Transfer just may be the solution. Burning food and the very things like the trees in this story that recycle CO2 out of the air and give us Oxygen is suicide. How could the government have passed the ethanol programs? Milk, eggs, meat, everything is going up in cost and the thing about it is that it takes more energy to plant, fertilize, harvest, and distill this mobile energy source than the amount of energy you can get out of the process. Do the research! Please post any numbers that you find especially the per meter efficiency of a corn plant or other crops to capture the suns energy. A solar transfer from the highest solar constant zones will prove to be the answer. We promise! and We told you so!
Posted by Manhattan2 (329 comments )
Reply Link Flag
About ethanol, that is. And mostly about the solar, provided that
one thing is recognized and dealt with. There is an incentive
with solar technologies to capture and attempt to use all the
light that falls on them. Since all the energy we use ends up as
heat one way or another, all the energy captured by a solar
collector (heat or PV) ends up as heat. The earth reflects about
30 percent of the incident light back into space, on average. If
solar catches on in a big way due to its perceived "greenness"
and its huge potential, eventually we will have to take into
account that we are capturing more heat than the earth naturally
would. So perhaps we should get used to that up front and make
solar collection technologies heating neutral by making them 30
percent reflective.
Sounds silly, I know, but eventually it will be a problem, as we
always "need" as much energy as we can get, and the potential
here is orders of magnitude greater than anything we have
known before. Might as well admit it up front and deal with it.
Posted by billmosby (536 comments )
Link Flag
Milk is $2.50
I commonly see milk at $2.50 a gallon in my area and often on sale for $2.00 a gallon.

If the trees that are going to be used in this experiment were already being cut down and the debris tossed away, wouldn't it be more ecologically sensible to recycle that waste instead of tossing it away?

If the material was going to be wasted and this plan can recycle it in a manner that removes the need for just that much more petroleum based fuel, then I don't see the problem.

There is a common myth going around that ethanol fuels will cause food prices to go up because of all the corn and other products that will be turned to fuel instead of food. It's a myth and been debunked repeatedly. Ethanol production uses the corn waste- not the kernels. All those stalks, husks, etc. All of that would otherwise be burned on the fields would then be collected and converted to ethanol. That is better for the environment and doesn't affect the food prices.

The government is *still* subsidizing farmers to intentionally not plant crops as a means to keeping the market price of food crops high. Imagine what would happen if all those millions of idle acres were turned to producing a product for ethanol instead? The government wouldn't be paying a subsidy, which means less money taken out of your pocket, the farmer could get a profit for crops grown and sold to fuel producers, and the cost of fuel for your own vehicle could potentionally go down.

It's a renewable resource.

I've done the research and all signs point to this being an ecologically sensible and friendly alternative fuel solution.
Posted by Vegaman_Dan (6683 comments )
Link Flag
Fuel for the near future
Ethanol will be just one of many solutions for the near future. All the arguments here are always about the perfect fuel .. yada .. yada.. lets start getting off of oil with many different technologies and stop being critical of each one saying its not perfect. Let the farmers make a few bucks for a while and cellulosic will also help out for a longer term solution. Ethanol is not a replacement just a supplement.
Posted by TomboSlicko (23 comments )
Reply Link Flag
Not really much of a supplement
It's pretty much a break-even proposition from an energy
standpoint. Which probably does make it near-term, once the
taxpayer gets tired of subsiziding it. Oh, but how long before the
government lets us stop subsidizing it?
Posted by billmosby (536 comments )
Link Flag
The latest solution
10 years ago it was "thermal depolymerization" ... Lets see how long cellulosic ethanol remains the panacea.
Posted by Clouseau2 (329 comments )
Reply Link Flag
no single solution
creating a bridge to any kind of viable nergy poliy means geting rid of single solutions.
solar, coal, wind...just words to replace "oil" in conversations that start "we all must".
business efficiences can drive conservation, as soon as business efficiencies are made necessary,
instead of "the way we have always done things" being the answer to every change.
hydrogen has a place. as an example, coastal wind turbines could be aimed at electrolysis off peak, with fuel cell power being added back in on-peak.
wood based ethanol, and methanol, take nothing from lumber. and the net is reducing th aste factor in pulp wppd prodiction.
coal is a subsidy from the planet is oil. used intelligently, the supply can last quite a while.
no single answer. no monloiths. all that sngls answer solutions have ever done for an economy is empower the few, and leave the rest complaining.
Posted by bridge solution (42 comments )
Reply Link Flag
Butanol is better for fuel
Drink the ethanol, burn the butanol.

<a class="jive-link-external" href="" target="_newWindow"></a>
Posted by willdryden (271 comments )
Reply Link Flag
fuel for the future
Hydrogen is the way to go
Posted by marspolarlander (8 comments )
Reply Link Flag
The real fuel of the future
oil derived from coal.
Well all this bio fuel requires more messing with nature for the worse whereas coal is just well there and theres plenty of it.
If you really want to help for your children you'll need to rethink what trully important rather than a fear driven new technologies market.
1) Oxidents in the air.
2) The cutting of trees
3) Bio-diversity

The odd thing is with all that C02 outthrere we look set to get more of all 3.
It's a good thing i can see into the future.
Posted by wildchild_plasma_gyro (296 comments )
Reply Link Flag
Valid point
I second that. Just because some energy forms are "natural" doesn't
mean that if we use them it is automatically good. Nature is already
using 100 percent of them for its own purposes. How can we
contemplate turning them to our uses without considering that
That's one thing nuclear energy has in its favor. An "unnatural"
energy source to support an "unnatural" level of human population.
Posted by billmosby (536 comments )
Link Flag
hemp and diversifying
For a backgrounder on that, look here:

<a class="jive-link-external" href="" target="_newWindow"></a>

Last week I read an article analysing the entire 'life cycle' of ethanol and coming to the conclusion it was a net-energy LOSS. From fuel use in farming to trucking feedstock to processing, and energy costs there, to trucking ethanol to point of delivery, and then the 3/5 (?) power ratio wrt gasoline.

Can't find link, my bad. Anyone know if this is a likely scenario?
Posted by NoVista (274 comments )
Link Flag
Demand for corn as feedstock has caused the price of eggs to go from 2 DZ for a dollar to $1.48.

I imagine a tub of popcorn at the mivie theatre will follow suit.

Seriously, we need to concentrate on crop residues, and alternative crops such as palm trees (which can grow in salty water) to use as fuel feedstocks.

In many applications, especially cooling, it would be more efficient to use Sunlight directly instead of collecting it with chlorophyll.
Posted by disco-legend-zeke (448 comments )
Reply Link Flag
Tripled? Go back to school and learn basic math.
$1.00 x 3 does not equal $1.48 genius.
Posted by hounddoglgs (74 comments )
Link Flag
Cost of Food, inflation and connecting the dots
Be careful when you first attempt to connect the dots that you know what it is you are talking about.

To all those that blame the cost on food solely with the price of feed stock are over simplifying the commodity market.

True their is a correlation between supply and demand, etc.
But so to is there a correlation between inflation and pricing as well.

But take some time to research the cost of your food stuffs with the cost of commodities over the last 30 to 35 years. You should find that in the last decade or so that the market for corn has been "soft" on a price stand point and supply has been more than ample for need.

Many factors will influence the price on your food dollar, some of which will not be seen at the raw commodity market.

It is good that we are looking at viable energy options.
I expect that what will be provided for as ethanol fuels will be comprised of blended ethanols. Mixing the cellose with the grain and sugar forms as the technology and the chemistry of production improves.

Key factor though when looking at our options is how many products each commodity can provide.
Bent grass as a market right now doesn't exist.
Growing a crop for one purpose isn't sustainable. Where as corn has been developed for many uses (from corn starch package peanuts (dissolve with water or slight heat and are edible) to various forms of foods and fuels.
Posted by thelunatick1 (2 comments )
Reply Link Flag
Land requirements
I looked at available land in the context of what is known about
resources needed to produce significant amounts of fuel from
biofuel resources. Current food inflation may indeed have many
causes. Producing anywhere near enough biofuel to make an
appreciable difference in even our transport fuel supply implies
land usage much greater than that currently used for agriculture
in the US. The danger is that some kinds of biofuel will prove to
be energetically economic enough to foster a growing biofuel
industry on its own. In that case, the incentive will truly be to try
to grow so much feedstock that it has serious implications for
food supply and cost. The alternatives would be either not going
down that road or to prepare to import biofuels and/or food.
Posted by billmosby (536 comments )
Link Flag
Real Value of utilizing Cellulosic materials
As our source of renewable fuel that starts out from the sun, this has a lot lower efficiency compared to producing hydrogen fuel from solar power. The best cellulose producing plants of this planet is at only 5% energy capture. A lot of the energy is spent evaporating the water from the plants, some are used for respiration and metabolism, and the 5% goes to products of photosynthesis. On the average most plants are only in the 1-2% energy capture range. And out of that let us say 5% best efficiency for producing cellulose, a lot of energy are subsequently lost when fermenting these to produce ethanol and other fuels. You will still have to spend significant amount during distillation and purification process to produce fuel grade products. Thus often, the entire process of energy capture from the sun is less than 2%, most likely with the current technology we could only realize less than 1% overall solar energy capture via this pathway.

Producing hydrogen is more than an order of magnitude better when it comes to conversion efficiency. For example, the direct splitting of water using a catalyst, solar concentrators to produce extremely high pressure and temperature can achieve a direct efficiency of 56%.

But let us say we use PV cells in a conservative estimate with today's technology, which are about 20% efficiency, and the splitting of water via electrolysis at high pressure at 70%, the overall capture of energy is 14% net in the form of hydrogen energy value which are in turn 300% times more better than the best plants of the world. Plants are never nowhere this mark. There is hope in single cell algae that are selected for their near direct production of plant oils though.

But the real value of converting cellulose into fuel is that it could help cut down incidence of large devastating and very polluting forest fires. We just have to divert the energy from these forest fires by proper management of forest litter. We have plenty of forest litter and understorey growth that have plagued many big fires in the US. Forest litter, urban wood waste, farm waste from hay or straws are all good sources of fuel. Rather than let them be and burn whenever nature or arsonists allows, these biomass with uncontrolled burns produce many air pollutants and other noxious emissions. Why not utilize these to produce fuel or electricity. As an example, several biomass powered electricity generating plants have significant emission reductions from the same amount of cellulosic materials, often by more than 90% on the average compared to those emitted during natural burns like forest fires. And the cost of controlling such wayward fires are often massive and there are tremendous loss of properties as well.
Posted by Joe Real (1217 comments )
Reply Link Flag
Joe R., Well written, where do you stand on residential PV solar
We are all for biofuels, Solar, and wind programs, but only those that are heading down a sensible path toward renewable energy sources. We continue to explain why putting panels on rooftops simply does not make sense but we are having a hard time getting our point across. Joe R. or others check out solartransfer and see if first agree with our logic and then see if you can clean up our delivery so others can understand to think twice before they go Photovoltaic Solar at their house or place of business. They could be doing 2-3 times better by following our plan. Tell Arnold and Al Gore to stop pushing solar panels just because they sound like a green solution. What agency out there makes sure that the programs some people put forth are viable concepts? Who was asleep at the wheel on the ethanol burning corn to make fuel concept? If we are going to improve our oil independence we need to not allow Senators, Governors, or Presidents to push ill-advised programs for a financial gain for certain states even if the overall energy capture of such programs are a financial and environmental loss. Someone must be making money but we are not sure the earth or our oil independence situation has improved? By the way who is making money off of ethanol? The small farmer? And what happened to all that talk during the Live Earth Concerts? Did someone make money there also?
Posted by Manhattan2 (329 comments )
Link Flag
re hemp
For a backgrounder on that, look here:

<a class="jive-link-external" href="" target="_newWindow"></a>

Last week I read an article analysing the entire 'life cycle' of ethanol and coming to the conclusion it was a net-energy LOSS. From fuel use in farming to trucking feedstock to processing, and energy costs there, to trucking ethanol to point of delivery, and then the 3/5 (?) power ratio wrt gasoline.

Can't find link, my bad. Anyone know if this is a likely scenario?
Posted by NoVista (274 comments )
Reply Link Flag
I've seen about as many studies supporting corn ethanol being a
slight energy sink as studies supporting it being a slight energy
source. Cellulosic? Conjectured to be better. No large-scale
Posted by billmosby (536 comments )
Link Flag
Do your homework before you blame price increases on biofuels people!
There is so little demand for biofuels in this country that it's laughable to think it is to blame for price increases you see at the grocery store today. Milk, eggs, etc., all are shipped to your local grocery store on a TRUCK that burns a lot of DIESEL (even more for food that has to be refrigerated). Those tomatoes you buy in the middle winter come from Mexico or Central America or points beyond. Do you think the producers, distributors, and retailers are going to absorb increased costs out of the kindness of their hearts? If produce prices do increase, then we can stop spend fewer tax dollars on subsidizing farmers, anyhow. And there is also something called inflation you might have heard of.
Posted by hounddoglgs (74 comments )
Reply Link Flag
Where does cellulosic ethanol come from anyway?
Cellulosic ethanol is ethanol produced from woody material and not from the grain. The idea behind cellulosic ethanol is that it doesn't use food stock to produce but can be made from corn stover, wood chips, grasses, or even algae. So cellulosic ethanol will not decrease the supply of corn and therefore will not affect the price of corn.
Posted by rshelton3000 (26 comments )
Reply Link Flag
What about grasses?
I thought there was talk of producing it from switchgrass,
sawgrass, etc. Will those absolutely not grow somewhere where
they could replace a food crop? If the economic incentive is there,
what would stop them?
Posted by billmosby (536 comments )
Link Flag
Cellulosic ethanol
The Swedes - at the Karolinska Uni in Stockholm - also say it's a possibility. They are interested like all countries with a big forest industry...
But to make it really economical, you need to use the waste left after making the alcohol for energy production or other purposes.
However, public transport is the first of many ways of reducing oil-dependency.
Posted by Lars Johansson (1 comment )
Reply Link Flag
Biodiesel is here, NOW, and it works very well.
Why wait for a future wonder product when we have a really good fuel right now?

To be sure, there's no such thing as a "perfect" fuel. Everything's got its drawbacks. Given the excellent emissions and the wide variety of things you can make biodiesel from (grease, soy oil, canola oil, etc.), and the fact that you can make it at home, it holds great advantages over ethanol. Fact is, you can't make ethanol at home. Okay, you could, but you run a good risk of blowing yourself/your equipment/your garage sky high by doing it. Brewing biodiesel does involve the use of some nasty chemicals, but if you educate yourself or take a class on it, it will come out all right.
Posted by haazah (1 comment )
Reply Link Flag
Biodiesel works out only if you are using waste grease because oil is such a tiny part of the plant, and that means a horrible overall energy harvest per acre.
Posted by Phillep_H (497 comments )
Link Flag
Cellulosic Ethanol needs more development
Ethanol seems to be a good thing, corn ethanol is blamed for driving up prices for nearly every consumable... Sugar ethanol is very strong in Brazil and has a great future; cellulosic ethanol simply needs more development. <a class="jive-link-external" href="" target="_newWindow"></a>
Posted by ronb42 (7 comments )
Reply Link Flag

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