University of Minnesota Professor David Tilman, Princeton University Visiting Scholar Tim Searchinger, Dartmouth Professor Lee Lynd and others involved in the debate over the environmental and social impacts of biofuels have published in Science magazine what amounts to a new manifesto on how biofuels can be done right.
The authors list five biofuel feedstocks that are the best in terms of sustainability — “lower life-cycle greenhouse-gas emissions than traditional fossil fuels and with little or no competition with food products.”
The authors conclude:
Three steps should be taken: meaningful science-based environmental safeguards should be adopted, a robust biofuels industry should be enabled, and those who have invested in first-generation biofuels should have a viable path forward.
The EPA’s proposed rule on the Renewable Fuel Standard was intended to outline a viable path forward for first-generation biofuels. The Best Case Natural Gas Dry Mill, the Biomass Dry Mill, and the Biomass Dry Mill with Combined Heat and Power scenarios outlined in the “EPA Lifecycle Analysis of Greenhouse Gas Emissions from Renewable Fuels” all produce reductions in greenhouse gases that come close to or exceed the 20 percent standard in the RFS. The EPA’s definition of the Best Case is: “Best case plants produce wet distillers grain co-product and include the following technologies: combined heat and power (CHP), fractionation, membrane separation and raw starch hydrolysis.”
The question will be whether anyone invests in these technologies or in additional biofuel production at all, given the current economic and social climate in which biofuel companies are operating. One possible factor in choosing the best biofuels ought to be how soon they can become a reality and whether they can be improved from there.
Filed under: biofuel, Biofuel Technology, Food and Fuel | Tagged: biofuels, Food and Fuel, food vs. fuel, life cycle analysis, lifecycle analysis, Science, Searchinger, Tilman |
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With a lawyer-lobyist anointed by this group, and with the unproven indirect land use change theory still on their agenda, that sends up a Big Red Flag. This group is acting like they have all the answers, and they do not. Their so called “consensus” is a positive shift with good intentions, however it is not a complete analysis of all the issues. And as long as this group continues to claim that indirect land use change is based on fact, when it is not, there will be no consensus.
Another red flag goes up when people try to analyze biofuels “in general”. Instead, we should talk about individual biofuels, not biofuels in general. Ethanol and biodiesel are way different animals. They are made from different feedstocks using different processes. They have very different fuel characteristics and are used in different engines. They have different emissions and different environmental footprints. They have different economic impacts on the economy and on the food supply.
Ethanol engine technology has recently taken a giant leap forward, beyond flexi-fuel, and this will dramatically enhance the environmental impact of the fuel. “Ethanol optimized” engines are now being developed that get better mileage than gasoline, but have all the power and efficiency of diesel engines, at a much lower cost and a much higher power-to-weight ratio. (Ricardo, Lotus, and others) This is made possible by exploiting ethanol’s 25% higher octane and faster flame speed than gasoline, even though it has 30% less btu’s. The old argument, that ethanol is limited by its lower btu content is invalid.
Biodiesel, a good alternative fuel, is oil based. In contrast, ethanol can be blended with up to 50% water and still combust. That is significant, because we have technology that can distill a gallon of ethanol with less than 3 kilowatts, blend it half and half with water, and then combust it in a genset that produces 23 kilowatts per gallon, using a conventional small engine. (MicroFueler “grid-buster”) The output could be much higher using an “ethanol optimized” engine, a gas turbine, or a fuel cell. These new ethanol technologies are viable for charging batteries onboard the coming plug-in hybrids, and what you get is a vehicle design with the potential to eliminate imported oil entirely.
Onsite ethanol-water – vaporized or reformed into hydrogen – could also replace natural gas used for CHP production power at ethanol refineries, disposing of waste water. That would significantly impact the environmental footprint of corn ethanol, by replacing newly mined CO2 in the natural gas – with recycled CO2 embodied in the ethanol. Surplus electric power could also be fed into the grid.
There are also plans to grow Algae on the corn ethanol refinery waste stream. Again, this would greatly improve the environmental footprint, while mitigating waste heat and nutrient-rich waste water effluent called “centrate”. Waste CO2 will be recycled through the algae, instead of releasing directly it into the atmosphere. This will likely be very concentrated heterotrophic algae grown in dark, insulated tanks, on a very small footprint of adjacent land. The sugars and nutrients in the waste water centrate will feed the algae, enhanced by CO2 feeding, and what we’ll get is algae biomass doubling every 6 hours under optimal conditions. Strains of heterotrophic chlorella have been documented to double every five hours. That is, if you grow it for maximum speed and biomass, rather than stressing it for oil production, which slows the growth rate dramatically. This obsession with oil is what’s slowing down algae development. Instead, when algae is grown for maximum speed and biomass, we get a smaller overall percentage of oil, but from a much bigger volume of biomass. You come out way ahead, because you get massive quantities of starch and proteins for co-products, and you still get your oil. Five different companies are reporting algal biomass yields of 65-220-270-300 and 330 TONS per acre per year.
Algae grown on the corn ethanol waste stream will provide additional onsite co-products: The carbohydrates will drop-in to the fermentation process, providing additional onsite ethanol feedstock or biogas digester feedstock. Algal proteins are complete amino acids that will enhance animal feeds and complement corn ethanol distillers grains. Algae as a high-quality complete protein feed supplement, is also a green chlorophyll hemoglobin oxygen-carrier-booster that will improve the health and productivity of dairy cows, hogs, poultry, meat cattle, and farm-raised fish and “seafood”. Chorella, a human supplement, which can be grown at corn ethanol refineries, is currently selling in bulk on the internet for about $18 per pound. And medicinal and nutriceutical Omega 3 Oils derived from algae are now selling for up to $500 per pound. Nutritional supplements for humans may become another revenue stream for the algae-corn ethanol industry. Algae is also a candidate for the production of localized bio-fertilizer, that would replace the massive amounts fertilizers now being made from natural gas and other fossil fuels. Algae can also become a major feedstock for bioplastics. Integrating algae production into corn ethanol production has a huge potential to enhance numerous branches of our economy and their respective environmental footprints.
So why isn’t Algae on the “Consensus” short list of recommended feedstocks? Because it’s way above the bar their trying to set, and because it blows the lid off of indirect land use change theory. Heterotrophic algae grown Onsite on the waste streams of corn ethanol refineries will trump cellulosic ethanol, which requires biomass to be grown, harvested, and shipped to a central location, and then stored, handed and processed – still viable.
“Corn-cane” is also in the works. That is corn with a sugary stalk. So far, crafting corn with a sugary stalk decreases the production of the grain. However, it’s just a matter of time, before we have corn with all the sugar of sweet sorghum in the stalk and all the grain of our current corn crop. This means that we would be able to extract sugary juice from the entire corn crop, not just the starch from 25% of the crop, and we’ll still have all the grain. This will improve the footprint and also make corn-based ethanol competitive with next generation ethanol.
Another cutting edge plan is the “Farmer’s Ethanol” integration system, that will also dramatically improve the environmental footprint of corn ethanol, while mitigating methane released from manure, and instead using it as an onsite resource. We will also be integrating algae and/or duckweed production into the “Farmer’s Ethanol” flow chart. This may give us a new generation of corn ethanol with a 5 to 10 fold return and an environmental footprint that is totally acceptable.
There is also a plan to purify corn ethanol byproduct distillers grains for human consumption, so you may soon see it mixed-in with other foods as a protein booster. Distillers grains purified for humans may also become a global food staple that will help to alleviate hunger. We are currently only taking the starch to make ethanol from 1 out of 4 bushels of corn. Every acre of corn used for ethanol also produces about 50 bushels of animal feed, which goes to producing food. The fuel vs food debate has been debunked, and so has indirect land use change theory.
Look at biofuels in the context of how they compare with conventional petroleum based fuels. Biofuels, such as ethanol and biodiesel, are derived from “recycled CO2” which is already in the air. Whereas burning petroleum based fuels adds more and more CO2 to the atmosphere. “Newly mined” CO2 released by burning fossil fuels has a far bigger environmental impact than burning biofuels made from “recycled” CO2. Yet the EPA does not credit biofuels accordingly.
Ethanol, biodiesel, and biogas release much lower levels of Black Carbon Soot. Whereas dirty fossil fuels, such as coal, heating oil, gasoline, diesel fuel, jet fuel, kerosene, bunker fuel also produce massive amounts of Black Carbon Soot, which heats the air and then settles out on the surface of water, snow and ice, where it causes additional solar thermal absorption. This could be a much bigger climate change factor than CO2. Yet the EPA does not credit biofuels for producing much less Black Carbon Soot than petroleum based fuels.
You also need to accurately measure the impact of conventional fuels, before you go comparing them to biofuels. By omission, the EPA’s hidden agenda has been to make petroleum based fuels look much better than they actually are, and to make ethanol and biodiesel look much worse than they actually are. The EPA low-balled the environmental footprint of petroleum based fuels by excluding data on crude oil extracted from energy intensive tar sands, oil shales, and deep offshore oil production. The EPA omitted the deforestation caused by huge open strip mining and tar sands pits. The EPA omitted the environmental impact of shipping foreign oil thousands of miles using dirty bunker fuel, one of heaviest producers of Black Carbon Soot. The EPA omitted the environmental impact of America expending 12-15% of our entire defense budget and the burning of billions of dollars worth of diesel fuel and bunker fuel, every year, in order to protect our foreign oil supplies. Next time you pull-up to the pump, add that to the cost of your fuel. Now tally the cost to protect domestic biofuel – Zero.
Lobbyists planted a provision into the Energy Independence and Security Act of 2007 that required all new biofuel production to be at least 50% cleaner than petroleum based fuels – Yet the EPA had distorted the environmental footprint of the measuring stick, fuels derived from crude oil. Lobbyists also added another provision that biofuels would be subject to indirect land use change, a misguided theory, before it was even scientifically proven, and before legislators even knew what it was.
Consensus? What consensus? There is no consensus to over-regulate biofuels at the expense of our economy. “Accounting rules should consider the full life cycle of biofuels production, transformation, and combustion.” (Tilman 2009) Then we must also hold petroleum based fuels to the same high standard.
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Aureon, do you have any new developments on using Hemp for biomass? I’d like to get into promoting biomass generators here in East Africa. I think it’s time people here got off the grid.
Great comment though…lots of interesting alternatives to creating biodiesel. How expensive is the algae process thingy??
Cheers!
Max “The IT pro”