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Biofuels cool planet biofuels makes gasoline from miscanthus

Published on February 26th, 2012 | by Tina Casey


“Kitchen Stove” Biorefinery Goes from Grass to Gasoline in One Hour

February 26th, 2012 by  

cool planet biofuels makes gasoline from miscanthus

The California biofuel company Cool Planet BioFuels has announced the successful test of a pilot biorefinery that can convert an acre of the giant grass miscanthus into gasoline at the rate of 4,000 gallons per acre. You read that right – the process yields straight, drop-in quality gasoline that is chemically identical to its petroleum-based cousin.

A word about gallons per acre

According to Cool Planet, 4,000 gallons/acre means that the process generates about twelve times the yield of a corn ethanol refinery. However, the company cautions that this figure represents optimal growing conditions. In the real world, given routine growing conditions for miscanthus in appropriate regions (primarily the Midwest), Cool Planet estimates a typical yield of 3,000 gallons per acre.

Cool Planet also notes that as an added benefit, some carbon could be diverted from the refining process and used as a kind of “terra preta” to enhance crop soil. That would decrease the production of gasoline but the yield is still pretty impressive. The company claims that the process will work on switchgrass and other woody biomass, and even agricultural waste will yield about 1,000 gallons per acre.

“Kitchen stove” biorefining

Cool Planet’s biorefining process requires a relatively low energy input at every stage. That starts with growing, since Miscanthus is a hardy perennial that does not require annual planting. The biomass prep stage is low-impact because the refining process is designed for crops that can be air dried to the appropriate moisture content while still in the field. No additional treatment is needed other than grinding. As for the refining, Cool Planet describes the process temperature as comparable to a “kitchen stovetop,” and the pressure barely tops that of a portable tire inflater. All in all, the conversion process from dried biomass to gasoline takes about one hour.

Thisclose to biofuel parity with petroleum

Taking into account only the feedstock and energy input, Cool Planet estimates that its biogasoline comes in at less than 60 cents per gallon, based on current commodity prices. That’s not what you would pay at the pump, obviously, but it does indicate that biogasoline is breathing down petroleum’s neck in terms of ahceiving price parity.

That day could be coming sooner rather than later. Cool Planet is readying a modular biorefinery design that can be planted just about anywhere that feedstock is available, and expects initial installations to begin within the next two years.

After that, it’s just a matter of sitting back and watching the grass grow.

Image: License Attribution Some rights reserved by Anton Novoselov.

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About the Author

specializes in military and corporate sustainability, advanced technology, emerging materials, biofuels, and water and wastewater issues. Tina’s articles are reposted frequently on Reuters, Scientific American, and many other sites. Views expressed are her own. Follow her on Twitter @TinaMCasey and Google+.

  • AKR

    If my memory is correct sometime in mid 1970s Mobil had a process of converting syngas into gasoline via catalyst route. So what is new in this? The gasifiers have been in existence since 1910 when Neils Bohr developed the first biomass gasifier.

    I think the promoters should tell the amount of energy in one gallon of actual gasoline that they have produced from how many kilograms of biomass and that should keep the record straight. But I guess all this hype is necessary for them to raise money.

  • B Wolfe

    Wow, this is pure wizardry! Put in some plant material, add some quantumnanocatalytic chemistry mumbo-jumbo, and alas, out come giant amounts of high quality drop in gasoline.
    Too good to be true? Indeed.

    5 minutes on the web and a 1$ handheld calculator will sober you up.

    These are the dire numbers:
    – Under the most optimal conditions, Miscanthus can yield about 11metric tons of dry biomass per (US) acre.
    – The total energy content of this biomass BEFORE any conversion is approximately 192,000 MJ (Miscanthus dry mass contains about 17.5 MJ/kg).
    – Gasoline has an energy content of approx. 134 MJ/gallon.
    – Thus to make 4,000 gallons of Gasoline, you would need AT LEAST (4000 x 134) 536,000 MJ in one form or another in your feedstock.

    So under the MOST OPTIMAL conditions, an acre of miscanthus could theoretically produce the NET energy equivalent of about 1,430 gallons of gasoline. And that is before the 40-60% energy-loss due to any conversion process.

    These kind of news stories, posting absolutely unrealistic numbers, undermine the credibility of the entire biofuels industry and let those companies with realistic szenarios and numbers look unattractive in the eyes of potential investors.

    I hope Google has done some research on the numbers before investing here. I hear they know a little bet about seraching information on the web 😉

  • Gromac

    you can’t tell the depth of the well by the length of the handle on the pump

  • mhd4now

    That biochar is a beneficial soil amendment is not is question here. The claims presented are.
    First, have you read the report you cite? I skimmed that report… ” Even under the most zealous investment programme, biochar production will ultimately be limited by the rate at which biomass can be extracted and pyrolysed without causing harm to the biosphere or to human welfare. Globally, human activity is responsible for the appropriation of 16 Pg C per year from the biosphere, which corresponds to 24% of potential terrestrial net primary productivity (NPP) 22 . Higher rates of appropriation will increase pressure on global ecosystems, exacerbating a situation that is already unsustainable…” hmmm….
    Second, “waste” is a manmade concept… there is no such thing as waste, or even surplus in the natural world.
    Third, if you go to Cool planets own press releases you will see where they state they can adjust the biochar output from N100 to nothing, depend on …. profits?
    Finally, whatever biochar can and can’t do, it can’t replace water. While it may reduce water usage, if the well is empty, the river dry, or the rains don’t come, no amount of biochar will make unproductive soil productive.

  • mhd4now

    Ok, let’s make it simple: Pyrolysis, good, but certainly nothing new. Biochar, good, but, again, nothing new. Indigenous people have been using it for millennium. Just because western man has “rediscovered” it, and western science is beginning to explain it, doesn’t make it new.

    When a group of properly pedigreed people seeking money start throwing around hip buzz words and make wildly optimistic claims at a time of uncertainty, it’s time to step back and study. They’ve provided little magic diagrams that show “waste” on one side, the ‘Answer to All Your Prayers’ on the other side, and, if you act now, you’ll get a bonus, absolutly free! Biochar, its a fertilizer, a carbon sequester, and a desert topping. Sorry if it sounds a little like cold fusion… or hot fusion for that matter.

    Pyrolysis has many forms, from a simple fire to a petro cracker. Some are “self sustaining”, other require significant inputs. “Self sustaining” methods (like, say, fire) yield little more than smoke, ash and heat. A “self sustaining” wood fire can boil water and cook meat, but will never melt steel. One industrially useful product of simple pyrolysis is charcoal. Charcoal is useful because it will burn hot enough to melt iron. If it’s all you have, then you use it, but it is not very efficient. You have to clear cut acres of forest to produce enough charcoal to produceenough steel to produce one car. In order to obtain industrially useful products, you must go beyond simple “self sustaining” pyrolysis. That is never explained on their website.

    And the whole claim of “carbon sequestration” needs a closer look. Per the video on sovlefor(x), their grass field will consume 10x the carbon of a similar size forest. Sounds incredible… until you acknowledge that the grass has to reabsorb the carbon year after year, while the forest have hundreds of years sequestration done. Upon even a simple examination, the claims of enormous sequestration go from incredible to incredulous.

    Then there is a huge amount of trust required in the whole notion of their intention to produce biochar for soil enrichment. Complete, high temp pyrolysis will break down all organics to hydrogen and carbon monoxide. ALL organics, to maximize producer gas production, to maximize butanol production. We have to take on faith that they will leave a certain amount of potential, let alone profitable, butanol production on the table so that they can return the matter back to the soil. Really? Oh, they might do some, for show, but the bulk of the organics that would have gone back to the soil to nourish it will undoubtably end up in gas tanks.

    And then there are the claims for biochar itself. While biochar is a very good natural soil enhancer, it will not make nonproductive soil productive, as is claimed. The most important thing that will make nonproductive soil productive is water. Agricultural water is already in short supply. There is the widely cited example of Saudi Arabian grain production, but that’s just the tip of the iceberg. China is losing miles and miles of farmland to encroaching deserts every year. The glaciers that fed the Indus and Ganges are disappearing. In the central valley of California, fruit trees are being ripped from the earth because the water to sustain them just doesn’t come from the Sierras like it used to. Biochar will do nothing fora desert. So theoneacreproducing two acres in a few years is probably theoretically possible, but in the real world utterly impossible without significant addition of unavailable water.

    And then there is the specious claim of hyper efficiency of 4000 gallons per acre for grass vs 300 gallons per acre for corn ethanol. The numbers may be correct, but it’s an apples and oranges comparison: a factual ‘slight of hand’. Corn ethanol is produced via fermentation of sugars from the kernels of the corn cob, a relatively small portion of the corn plant. The so called Switch Grass ethanol’s claim to fame was to use to use sugars locked with the cells of the entire plant, but it still just the sugars, because they are easy to ferment. Much of the plant, the cellulose and other longer hydrocarbons, are not processed at all. Pyrolysis can break down the entire plant structure, all of it, to H+CO, from root to leaf tip. This claim says nothing about the efficiency of pyrolysis, just notes the inefficiency of fermentation for fuel production. Fermentation process does excel at producing that other alcohol, though.

    On top of all that, we have to believe when they claim this will not impact food production. Really? Even if they remove just the so-called crop waste from the fields, the loss of organic matter (not char), will lead to the soil losing water holding ability, drying out, eventually being depleted and washing away. If farmers do remove it from the fields, they do so to create silage, which is a food extender for cattle, and then return it to the land as manure. So this “waste” isn’t really waste. It’s vital to the health of the soil. This would represent really, really bad soil management. Many farmers would not allow this raping of the soil, and no farmer could allow it for long. Even if they did, even at 3000 to 4000 gallons per acre, what then?

    Well, per their slide show, they think they would build 2,000 facilities in the developed world producing 50 million gallons per year, each. Wow! Then, they would build 100,000 facilitiesin the developing world producing 1 million gallons per year, each. OMG! So, all told, they would get, wait for it… 200 billion gallons per year… optimistically… probably… pretty sure, maybe. Well, its a start. Actually, it’s about half of what we use every year, world wide. While it matches what we use in the US, worldwide transport word use is climbing rapidly.

    The long tail of this dog is continued reliance on fossil fuels. That’s right, more CO2 producing oil. This will never meet all of our present or future needs for transport fuels. Rather, when used in conjunction with existing petroleum reserves, it will extend ouruseof gasolinewellinto the future. So rather then working to build a carbon neutral, post petroleum world, we will expand our petroleum based infrastructure into the future and into the developing world, as we continue pumping out massive quantities of CO2, continuing to heat the atmosphere, and merely postponing the day we will have to face peak oil.

    Then the worlds dozen or so billion people will have to go into the ultimate carbon sink (other than the earths crust), the arboreal forest. At the end of the day, the amount of “concomitant benefits of biochars for Soil Carbon Sequestration” will benegligiblecomparedto the destruction of hundreds of years of carbon sequestration the cleared forest has already provided. This is an ‘Answer to All Your Prayers’only ifyou’reanoilman…I’m surethey got lots of “big investors”.

  • Tom G.


    I hope you get this message because it seems everything I post goes to moderation. Anyway you can get a very good review of the process by going to Google’s site called”


    At that site you will hear from many individuals who are working to solve some of our most pressing problems. I hope you enjoy the site.

    • Ross

      The presenter of that is the president of CoolPlanet but it appears to have some credibility. Google also appears to be an investor in them.

  • mhd4now

    Sounds like pyrolysis. Organic material goes in, add heat (lots of it), then viola, producer gas and pure carbon comes out. Saw this first in middle school science class. The original gas light utilities used coal as the organic (organic in it’s chemistry usage), also wood alchohol was produced this way.

    The issue is the heat source for the pyrolysis. Typically fossil fuels are used, but I doubt this is the case here. Sundrop was developing a solar powered versionof this until they were co-opted by Chesapeake last summer. The producer gas itself can be used, but this will decrease yields.

    At high enough temps, the output is pure producer gas, hydrogen and carbon monoxide with trace minerals. Pure producer gas is readily converts via catalyst to butanol (I.e., gasoline). Long story short, nothing new here.

    This limiting factor here is not the tech, but the inputs… as has been stated. As has been stated by Bob_W, we use lots of transport fuels, which means lots of land cleared… If land is cleared just for fuel, this will not be carbon nuetral! If crop “waste” are removed from the feilds, and little more then carbon returned, this will be a detriment to the soil. But apperently desperation… eh hhemm… I mean hope, springs eternal. But the reality is our demand will rapidly outstrip our supplies of liquid fuels. We may never run out, but wewill never have it so affordable again.

  • Erich Knight

    Some of the newest work with char show a savings of 74% of NH3 when used as a compost bulking agent.

    Short a nano material PV / thermoelectrical / ultracapasitating Black swan,
    What we can do now with “off the shelf” technology, what I proposed at the Commission for Environmental Cooperation, to the EPA chiefs of North America.
    The most cited soil scientist in the world, Dr. Rattan Lal at OSU, was impressed with this talk, commending me on conceptualizing & articulating the concept.

    Bellow the opening & closing text. A Report on my talk at CEC, and complete text & links are here:

    The Establishment of Soil Carbon as the Universal Measure of Sustainability

    The Paleoclimate Record shows agricultural-geo-engineering is responsible for 2/3rds of our excess greenhouse gases. The unintended consequence, the flowering of our civilization. Our science has now realized these consequences and has developed a more encompassing wisdom. Wise land management, afforestation and the thermal conversion of biomass can build back our soil carbon. Pyrolysis, Gasification and Hydro-Thermal Carbonization are known biofuel technologies, What is new are the concomitant benefits of biochars for Soil Carbon Sequestration; building soil biodiversity & nitrogen efficiency, for in situ remediation of toxic agents, and, as a feed supplement cutting the carbon foot print of livestock. Modern systems are closed-loop with no significant emissions. The general life cycle analysis is: every 1 ton of biomass yields 1/3 ton Biochar equal to 1 ton CO2e, plus biofuels equal to 1MWh exported electricity, so each energy cycle is 1/3 carbon negative.

    Beyond Rectifying the Carbon Cycle;
    Biochar systems Integrate nutrient management, serving the same healing function for the Nitrogen and Phosphorous Cycles.
    The Agricultural Soil Carbon Sequestration Standards are the royal road for the GHG Mitigation;

    The Bio-Refining Technologies to Harvest Carbon.
    The photosynthetic “capture” collectors are up and running all around us, the “storage” sink is in operation just under our feet, conversion reactors are the only infrastructure we need to build out. Carbon, as the center of life, has high value to recapitalize our soils. Yielding nutrient dense foods and Biofuels, Paying Premiums of pollution abatement and toxic remediation and the growing Dividend created by the increasing biomass of a thriving soil community.

    Since we have filled the air,
    filling the seas to full,
    soil is the only beneficial place left.
    Carbon to the Soil, the only ubiquitous and economic place to put it.

  • Bob_Wallace

    Interesting, with a very interesting price. But the land required…

    Last year we burned about 380 million gallons of gasoline per day. At 3,000 gallon per acre it would take about 127,000 acres or 198 square miles of land to grow one day’s gasoline.

    That’s 72,500 square miles to produce a year’s supply. More than the land area of the state of Washington (18th largest) and roughly the size of the nine smallest states combined.

    A lot of land. A lot of jobs. Carbon neutral or better. (Plant root systems fix carbon beneath the soil.)


    Income from an acre of corn is likely in the $200 – $300 range. If we started making biofuel on a large scale there’s a good chance food prices would go up significantly. The farmer would need to sell their plant matter for only “$0.10/gallon” to force other crops out of the field.

    • Ross

      It isn’t just the root system. It is the biochar/charcoal bi-product of the process which can in turn be used to improve crop yields.

      • Bob_Wallace

        Have you seen any data on the amount of biochar which might be obtained after the “gasoline” is extracted? A bunch of the carbon is going to go to the fuel produced.

        They aren’t just squeezing out the juice, they’re breaking down the plant material itself.

        • Ross

          Their website says it has an “N100” rating which they say means as much carbon goes to biochar as into the fuel itself.

  • Gerry

    The midwest is certainly a proven place to grow corn, but I wonder if the Pacific Northwest, where the nation’s grass seed is grown, might be even better for a perennial grass, because the long, wet growing season is perfect for growing grass, and winter temperatures are mild, so the grass would stop growing only briefly, or not at all. In the rainless summers, drying could be done in the field.

  • Ross

    Drop in replacement
    High yield
    Long term sequestration in biochar

    It would only take a fraction of that to be true for it to be great news.

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