Cellulosic Ethanol from Rice Straw Plant Being Built in California

Ron Kotrba has written an incredibly interesting article for Ethanol Producer Magazine about a company which hopes to soon be making ethanol from rice straw in California.  Currently, California rice farmers must pay $25 to $45 per acre to have the rice straw baled and removed from their fields.  Colusa Biomass Energy Corp. (CBEC), the company which is currently in the process of building their first plant to process rice straw, has offered to take it off their hands for a mere $15.  There is a general understanding that once the plant is built CBEC will be removing the straw at no charge.

Rice straw has limited other uses since it has a very high sodium silicate content which is not palatable to livestock and is very abrasive for machinery.  CBEC intends to separate the silicate and use it as an extra revenue stream, selling it to a range of manufacturers.

The plant will be relatively small, processing “35,000 acres of rice straw into 12.5 MMgy of ethanol and 33 million pounds of sodium silicate.”  This is not necessarily a bad thing however as it will cut down on average transportation costs to the plant.  Generally 3.5-4 tons of rice straw can be collected per acre.

The amazing thing is that CBEC will be doing this with no federal or state money.  They have generated enough investor interest to fund their project via investment capital.   CBEC has been doing small scale research for years, it is only relatively recently that they hired Harris group, a respected engineering firm to do an analysis to see whether their research can be scaled into an economical, large scale, continuous process.  Harris group seems to think that this is doable, so the project is moving forward.

The actual process is described by the article to work as follows:

“We wash it, then introduce a mild solution of a strong acid then [which] hydrolyzes out the lignin and the hemicellulose,” Bowers says. “Then a second hydrolysis process occurs where we extract the cellulose from the remaining substrate.” He says the process whereby CBEC hydrolyzes the substrate, removing most of the lignin and all of the silica, is proprietary. “We have designed the hardware and the software to propel a reverse osmosis custom filtration device that we built to do the extraction,” Bowers says. “Through filtration, we separate the silica out and precipitate it as silica sodium oxide, and from the other side we pull out the lignin.” Once the lignin is dried down, CBEC plans to use it as boiler fuel. The company’s sales forecasts indicate the ability to retrieve 34-cents a pound from the more than 33.5 million pounds of sodium silicate, a versatile compound used to make everything from micro-electronics to toothpaste.  Once the cellulose and hemicellulose are separated from the lignin and silica, fermentation begins. “Our fermentation will look just like the corn guys’,” Bowers says.”

I hope that they don’t look exactly the same, if CBEC tries to break down the cellulose like corn starch (using amylase), they are going to be sadly mistaken.  They will be needing to use cellulase which as far as I know still acts more slowly than amylase and will be considerably more expensive.  I wonder whether they are going to just take on the cost of the cellulase or if they have figured out a plan for this expensive item too.  I would be extremely interested in the details of how exactly their second hydrolysis process works as well.

“We’re considering separate five-C and six-C lines”–and how do they propose to enzymatically break down the hemicellulose? I could be very mistaken but as far as I know there is not yet an economical way to break down hemicellulose since hemicellulose consists of so many different sugars.  You would need a multitude of enzymes each being unique to the sugar that they attack.  They could break down the hemicellulose via acid hydrolyis however but that is questionably economical.

Anyway, the company hopes to expand to 11 refineries by 2012 located in California, Texas, and Arkansas.   In the long term they see a lot of potential for global expansion since rice is such a staple crop world wide.  Whether they succeed or not, I guess we will have to wait and see.

Senate Farm Bill Might end up Different from the House Version

The US house of representatives last week passed a farm bill which seems to be very generous to those who produce crops for ethanol.  Currently farmers who on average earn less than $2.5 million per year are eligible for crop subsidies.  The senate bill may reduce this limit to $1 million a year.  Some senators also want to reduce the maximum payment to farmers from $360,000 to $250,000.  The senate bill will also likely include a similar loan guarantee program for cellulosic ethanol plants to the $2 Billion which has already been passed by the house.

“Sen. John Thune, R-S.D., said Tuesday he supports plans to aid farmers in the cellulosic ethanol movement, saying incentives will be necessary to encourage farmers to grow certain crops.

“We have to have an economic driver for this thing,” Thune said.”

Unfortunately the problem with providing subsidies as incentives is that it will put the government in the position of picking winners and losers.  A carbon tax would be more fair, cheaper, provide less opportunity for loopholes, and would be a more efficient mechanism for transitioning to biofuels since the transition would be market driven.

In general, it looks as if the Senate is trying to write the bill to be more in the interest of small farmers than the house version.  Whether this is a good thing or not is a matter of personal opinion.

University of Wisconsin Madison Undergrad Researches Techniques to Grow Algae as a Potential Source of Biomass

Jennifer Jackowski, a senior majoring in botany at the University of Wisconsin Madison is studying algae growth in local lakes. “This summer, she placed four, 30-foot fiberglass screens in Lake Mendota, which she hopes will act as floating beds for algal growth. Her primary goal is to devise a means for cleaning the lakes. But she also plans to study the algae to see if it holds any commercial value.”

Seth Keel, a researcher and co-founder of the Madison-based consulting and distribution company Great Lakes Bio-Fuels, is also looking into the potential of algae. Keel hopes to develop a commercial process to make biofuels from algae that will be competitive with traditional fuels. With the recent global surge in biofuel interest has come a lot of money in the form of investment capital. This will help speed the development of economically competitive biofuels as there will be more people available to work on making breakthroughs and they will have better equipment with which to make the breakthroughs.

“Both Keel and Jackowski envision a process in which algae is harvested from the lake — in Keel’s case, by pumps, and in Jackowski’s, via screens. This kind of cleaning would have a double effect — the algae is removed from the lake and future algae blooms would be diminished because the nutrients from the algae would not be recycled in the water to be used by following blooms.” Whether this is good for the lakes or not has yet to be determined.

Although algae is orders of magnitude more productive in terms of mass per acre per year than traditional bioenergy crops, the costs of the processes of obtaining and processing the algae are also currently magnitudes higher. More research is definitely necessary but from what I can tell we will be seeing mass production of other more traditional forms of cellulosic ethanol (wood, switchgrass, etc) far sooner than from algae simply because the algae process is far more complex and will require more time to engineer. With the enormous potential of algae it certainly is not an option to be overlooked however.

Popper, Ben. “Long green seen in algae in city lakes” Wisconsin State journal, July 30 2007, <http://www.madison.com/wsj/home/local/index.php?ntid=203326&ntpid=1>

Researchers and producers optimistic about sweet sorghum as biofuel feedstock

Sorghum, a plant genetically similar to sugarcane is being considered as a future biofuel feedstock.  Many researchers, funded by both government and industry are breeding sorghum for traits desirable in bioenergy feedstock.  There are hundreds of sorghum varieties throughout the earth.  They are being bred to increase per acre yields, to increase drought resistance, and increase sugar content.  The sorghum genome is being mapped which will help scientists understand which genes do what, which will allow them to better control sorghum breeding.

Sweet Sorghum is being especially looked at for a number of reasons.  It requires roughly half the water per acre when compared to corn.  By it’s nature, it has a high simple sugar content (like sugarcane) which makes processing into ethanol easier.  Current models are expecting sorghum to be produced at roughly 20 tons per acre. This exceeds even miscanthus which comes up at roughly 15 tons per acre.  This would be economically competitive with gasoline.  Sorghum is also naturally drought resistant which will allow it to be planted in areas too dry for corn.

A lot of work right now is going into changing sorghum from a seed crop, which requires replanting every year to a perennial.  Perennials are easier to grow since the relatively costly process of planting every year can be neglected.  This happened with sugarcane in Brazil, so it is not unheard of.

A lot of the sorghum research currently is going on in Texas since the climate in Texas potentially could be ideal for mass sorghum production.   A lot more research is needed into this promising potential biofuel however as there is still a lot of uncertainty about the plant.

Maryland Drought Hurting Corn Production, Would Cellulosic Alternatives Fare Better?

As the article Water, Water, Everywhere, But Not a Drop to…..Farm With describes, Maryland is currently experiencing a period of extended drought.  “in the opinion of Earl “Buddy” Hance, a fifth-generation farmer in Calvert County and the state’s Deputy Secretary of Agriculture, it’s the worst in a quarter-century” The effects of this drought are obviously having an adverse effect on Maryland’s agricultural industry.  Many farmers in Maryland planted more corn than they have planted in years past due to the increased demand for ethanol.  These farmers had expectations of cashing in on $3.50/bushel crops of corn (as opposed to the typical $2.10/bushel) and instead are going to lose much of their fields.  They are seeing their plants shrivel and die from lack of water.  Maryland’s governor Martin O’Malley has asked federal authorities to declare a drought disaster in parts of the state which would allow farmers to be awarded disaster relief aid.

The question of the day is: would cellulosic crops be faring better in this situation?  I looked into drought resistance.  Switchgrass and Miscanthus both seem to be moderately drought resistant.  They both have relatively deep root structures which can thus find water in periods when plants with shallower root structures (corn) cannot.  It is also definitely easier to grow these perennial grasses than corn.  I was unable however to find reliable numbers detailing miscanthus, switchgrass, poplar, and corn water usage requirements.  If any readers have a source for this data please let me know as I am curious and will happily do a follow up if I can get some good numbers.

Jeff Broin on Cellulosic Ethanol

Jeff Broin, President and CEO of Poet is interviewed by Stephen Lacey in a podcast on Inside Renewable Energy. Poet is the leading dry mill producer of ethanol in the US. Broin talks first about Poet’s corn ethanol production and some common misconceptions with that process. He then talks about Poet’s cellulosic research including their recently announced initiative to turn corn cobs into ethanol via cellulosic hydrolysis. More information about Poet can be found here.

Just a heads up, the first 10 minutes or so of the podcast are spent talking about wind turbine shortages (which is pretty interesting and worth listening to none the less).

The Science Behind the Farm Bill

The Center for American Progress is running an article titled the Science Behind the National Farm Bill.  The article is about biofuel legislation that will be included in the farm bill which will soon be voted on by congress.  The Center has put together a quick guide that they are calling Biofuels 101: A beginners Guide to Renewable Energy.  It details the merits of traditional (corn) ethanol, cellulosic ethanol, and biodiesel.

As this is a site about cellulosic ethanol, I wont worry about the corn ethanol or biodiesel sections.  I would like to correct a couple points that they make in the cellulosic section however.  First they say that the process for refining cellulosic ethanol is more environmentally friendly than the process for refining traditional ethanol.  This is not true, both processes can be incredibly clean depending on the preference (and budget) of the manufacturer.  They also say: “cellulosic fuels can yield twice the energy output per unit of energy input than corn ethanol.” Actually it can potentially yield far more than twice as much energy as corn which has an energy input to energy output ratio of roughly 1:1.6 currently.  “The process to derive ethanol from cellulose involves using enzymes to break down the tough and resistant cellulose in plant cell walls into sugars.”  They completely left out acid hydrolysis.  Although many believe enzymes (cellulase) will be the future of the industry, at the moment acid hydrolysis is at least as common as enzyme hydrolysis.  A lot of research currently is going into using an acid pre-treatment with an enzymatic attack.

Anyway, it is at least an interesting read for anyone completely unfamiliar with the biofuel industry.

Hybrid Poplars: Energy of the Future?

It seems that for a while now I have been reading about how hybrid poplar trees are a potential source of cellulose for cellulosic ethanol. Every time they have been mentioned it I always thought, no way, trees grow far too slowly to be competitive with the likes of miscanthus and switchgrass. Apparently I have been mistaken. A couple days ago I read an article about ongoing research at Purdue to decrease lignin content in hybrid poplars to both increase cellulose content and increase the ease with which the cellulose can be broken down. Since then I have been reading more and more about these amazing trees and my past bias against them seems to have been flawed.

It turns out that hybrid Poplars can grow 10 feet per season. This can mean as much as 10 tons of wood per acre per year. If lignin content can be decreased somewhat (plants need at least some lignin just to hold the rest of the components together), and yields can be further increased, poplars could potentially be a serious contender for widespread utilization. This basically means that currently poplars would yield 700 gallons of ethanol per acre per year which is about the same as switchgrass although somewhat less than miscanthus. That is before any % lignin modifications or yield increases.

Poplars require very little maintenance once planted. “In the first year, weeds must be controlled using herbicides and/or mechanical methods. Additional weed control may be needed in years 2 and 3, but once the canopy closes, weeds are shaded out and further weed control is generally not needed. Insecticides are applied if necessary to control cottonwood leaf beetle during the rotation. Fertilizer applications are minimal and are called for only if nitrogen levels in the leaves fall below 3 percent on a dry weight basis. Typically this means that one or two applications of nitrogen of up to 50 lbs/acre (56 kg/ha) are required during the entire production cycle. Harvest utilizes standard forestry equipment widely available in the U.S.

As perennial crops, production of hybrid poplars can offer substantial environmental benefits compared to annual row crop production. Chemical and fertilizer applications are considerably lower, lessening the potential for chemical runoff and leaching. Hybrid poplars, as buffer strips, also intercept runoff of nutrients from fields near streams, rivers and wetlands. As perennial cover, wind and water erosion over the life of the rotation is less than that with annual crops. Hybrid poplars also provide increased year-round habitat for birds and small mammals compared to annual row crops.”

Poplars are similar to switchgrass in terms of the effect they have on soil carbon. Both have dramatically beneficial effects on the top-soil. There are two reasons for this. First, poplars form extensive root systems which decompose when the tree gets harvested (and thus killed). Second, every year when the leaves fall, they decompose and add to the fertility of the soil. These crops are especially better than corn in terms of soil fertility.

What SHOULD we do about our energy predicament?

At the moment there is a 51 cent per gallon subsidy on all ethanol. Many in the ethanol industry are also asking for a further 75 cent per gallon subsidy for cellulosic ethanol to aid the transition from corn to cellulosic raw material. The argument for these subsidies is that ethanol (especially cellulosic) is still a growing industry thus it needs help in order to grow to replace it’s predecessor (big oil). People also point out the environmental and political benefits of using ethanol. Current subsidies are expected to expire in 2010 and will be reevaluated at that time. The current proposal by democrats is to add a 50 cent per gallon subsidy to cellulosic ethanol which will expire with the already existing ethanol subsidy in 2010. There is a lot of opposition to additional subsidies since the government which is already short on funds has spent $5.1 billion on existing ethanol subsidies in the last year alone. This number will inevitably continue to increase as ethanol usage ramps up. Additional opposition comes from livestock producers who are concerned about increasing costs of livestock feed.

There are several other ethanol related proposals in congress as well. Loan guarantee programs which would reduce risk for investors by allowing the government to take on some of the investment risk (and decrease interest rates on loans) are being considered. Another proposal is to provide funding to community colleges to begin biofuel technician training programs to provide workers for the industry. Currently there is a 30% subsidy to gas stations who install E85 pumps for the cost of the installation, this subsidy could be enhanced. Finally, research into a trans-continental ethanol pipeline is being considered to reduce transportation costs of the product. Existing gasoline pipelines can not be used since they run the risk of water contaminating the product.

To me it seems that additional subsidies are not the way to go. Sure they might be a relatively effective way to transition the country to biofuels, but at the cost of further bankrupting the treasury? A better way to encourage ethanol usage would be to implement a broad carbon tax. This tax would not only apply to gasoline, but all non-renewable carbon sources. What if it started out as a 15 cent per gallon tax on carbon emissions from gasoline. Every year this number would increase by an additional 15 cents per gallon for the next 15-20 years. While not immediately overly painful for consumers, gasoline wasting habits will definitely be reduced in the long run. There will be far less people commuting 2 hours each way to work driving SUV’s that get 15 miles to the gallon while being the lone occupant of their vehicle if they are spending so much more on fuel for their vehicles. Not only will this act to decrease waste, it will generate revenue for the country which can be used to fund environmental initiatives. The notion that such waste of resources is acceptable is ridiculous. A kilowatt hr value can be calculated for a gallon of gasoline so that the tax can be equally applied to coal and other non-renewable carbon based power generation which will encourage alternative power generation and less electricity usage in general.

The US spends a lot of money to protect our oil assets and interests in the middle east. Further taxing gasoline and other forms of oil would be an additional measure that would generate a revenue stream to help fund this asset protection. Those who benefit the most from the oil (people who use the most) should be responsible for paying a higher share of the cost to protect our flow of oil. This tax could be transitioned the same way as I mentioned the previous tax would be enacted. Perhaps in smaller increments however (maybe 5 cents per gallon per year). This would not apply to coal since most coal that we use actually is mined in this country thus it does not need defense. The revenue generated by this program would go to national defense.

A final measure that I would propose would be either a tax or a subsidy to car buyers depending on the mileage that a car gets. The highway and city mpg would be averaged. If a car that is bought in say 2008 gets less than 23 miles per gallon let there be a $100 tax per mpg less than 23 on the purchase price of the car. So if a car gets 18 MPG there will be an additional $500 tax on it. If a car in 2008 gets between 23 and 33 mpg, there is no tax and no subsidy. If a car gets over 33 mpg, there would be a $100 government subsidy on the cost of the car for each mpg over 33 it gets. Every year the lower and upper bound would increase by 1 which would maintain a 10 mpg difference between the two bounds while transitioning the country into higher fuel efficiency standards. Those who want to buy cars that are big and wasteful can, but they will be paying someone else to drive a smaller car to offset their wasteful emissions (the tax revenue generated would fund the subsidies). There would obviously need to be exceptions. For example, we do not want to discourage usage of services such as commuter vans. There will also need to be limits put on maximum subsidies allowed or else the government could potentially be paying people to have cars. A separate set of standards would also need to be adopted for motorcycles and other transportation classifications (airplanes, busses, etc). Perhaps a $100 subsidy could be given to all flex capable vehicles as well.

I would allow the current subsidies to be phased out when they expire in 2010 with the exception of cellulosic ethanol which I would extend another 5 years to encourage breakthroughs. I would not however add any additional subsidies for cellulosic ethanol at the moment. With the additional taxes on gasoline, ethanol will be competitive and thus will not need the subsidy. By allowing a slow transition period people will have time to move if they decide to or find a job closer to their homes. In Europe it is abnormal for people to work in a different city than they live, thus they use far less fuel commuting. The US should be working towards this so that we waste less.

Cellulosic ethanol will help and is a solution but it is definitely not THE solution to our energy issues. Most of the oil usage reductions will come from cutting waste. Monetarily penalizing those who waste is a very good way to discourage it (as opposed to making it cheaper to waste via subsidy). In the mean time it is also a very good way of generating revenue for a government trillions of dollars in debt. Although the numbers that I listed are relatively arbitrary (in order to determine optimal numbers research will need to be done), they do seem relatively fair. There will be winners and losers no matter what we do (those who like big cars and commute a long way to work will be the losers here). We need to do something though so why not try to waste less so that this can actually work?

2007 Farm Bill may Allow Farmers to Plant Energy Crops on Would-be Fallow Lands

A lot of land is currently kept fallow by the US government for environmental reasons. This land which the government either owns or pays farmer not to plant crops on could potentially house cellulosic energy crops which generally lead to less environmental damage than corn and possibly even environmental recovery (depending on why the land was in trouble). Potential energy crops like miscanthus, switchgrass, and poplar trees actually increase the carbon in soil whereas corn generally has negligible effects on the carbon content of topsoil. The extensive root systems of these plants also works to decrease erosion since they hold on to the soil. Corn, not being a perennial and only lasting 1 year does not form as extensive of a root system thus farmers often have problems with their topsoil being eroded.

“The U.S. House version of the 2007 farm bill will contain a provision to allow farmers to plant cellulose ethanol crops such as switchgrass on some environmentally sensitive land that the government pays to keep fallow, lawmakers said.”

I am no expert on the subject, but this does not seem to be a bad idea as long as they do enough research to know that the land which is planted on will not be damaged further by energy crops. This will be somewhat tricky to implement in a fair way however. One possible idea for dealing with land which is already owned by farmers and the government is paying them to keep it fallow would be to simply continue paying them while allowing certain crops to be planted so that the farmer will not assume any risk and only potentially will receive a reward if the economics work out the way that we hope. These payments can then be reevaluated in 5-10 years depending on whether the farmers are indeed making money off of the energy crops on the land.

The government land which gets earmarked for energy crop growth could be lent to any corporation willing to sustain the land and grow energy crops on the land while requiring that they process the crops into ethanol and that they abide by guidelines that will protect the land. If there are multiple corporations that are interested in a given piece of land, instead of simply being given to someone, the land can be auctioned to the highest bidder for a certain rent per year. Allow all of these contracts to last 10 years, and then they can be reevaluated. The 10 year period will allow the industry to have matured so that farmers can be confident that energy crops will be able to support them and sustain their way of life. In the mean time this will provide a foundation of knowledge which will allow other farmers to begin switching the portion of their land which is currently allocated to corn ethanol to other more efficient energy crops.