Algae vs. Cellulose

We have reported on the state of cellulosic ethanol development, and the potential of cellulosic ethanol, in our recent feature entitled (not surprisingly) “Cellulosic Ethanol.” But if you take an interest in the future of biofuel, this is only half the story, if that. What about biofuel derived from algae? Despite the title of this post, it isn’t an either/or choice, and comparing the potential of algae versus cellulose as a biofuel feedstock is an interesting topic – both claim immense potential and neither are here yet. Will both of these biofuels end up in industrial scale production in the next few decades? Here are some comparisons:

(1) Algae can be converted into ethanol or diesel, depending on the process. Typically algae is associated with biodiesel, and cellulose is associated with ethanol.

(2) Cellulose has an extremely diverse array of potential feedstocks, but the quantity of many cellulosic feedstocks are significantly affected by seasonal variations. Algae, on the other hand, can be grown in ponds where conditions are precisely managed, or even in enclosed tanks.

(3) Cellulose feedstock, generally speaking, has a much larger geographic footprint than proposed algae designs – tinder harvesting from forests, vast plantings of winter cover crops, and extraction of agricultural waste, for example, require the cellulosic harvesting infrastructure to be more or less pervasive across the landscape – not necessarily in a bad way. Algae ponds, like dedicated cellulosic crops, are far more concentrated, promising fuel yields as high as 25,000 gallons per acre per year, or more – but these are very early projections. Algae grown in enclosed tanks have an even higher theoretical limit to their yield per acre, since they can build upwards.

(4) Both algae and ethanol can be grown utilizing waste streams. Algae ponds, or enclosures, can be nourished with CO2 from fossil fuel burning utility power stations, for example. Ethanol can be directly extracted from syngas or flue gas. Fossil fuel emissions can provide feedstock or nutrients for both algae and ethanol.

(5) Cellulosic feedstock for ethanol is available now, with the exception of dedicated crops that deliver some of the higher projected yields. But everything else; forest tinder, crop residue, municipal waste, etc., is already waiting for harvesting. Algae feedstock is not clearly ready – there have been successful experiments with regular algae, but most companies pursuing this technology are attempting to modify algae into strains that are more commercially exploitable.

(6) For both of these very promising feedstocks, algae and cellulose, we are going to wait a few more years before we’ll hopefully get a clear indication as to whether or not they truly emerge as major sources of transportation fuel.

Three very interesting companies working on algae to fuel technologies are Algenol, Greenfuel, and Sapphire Energy. Two companies working on interesting cellulosic ethanol technologies are Coskata and Mascoma. There are hundreds of companies currently pursuing algae and cellulose solutions to our energy challenges.

9 Responses to “Algae vs. Cellulose”
  1. With all the urgency of carbon dioxide capture from coal electric plants, why aren’t algae systems being tested on commercial basis? If algae aren’t ready, why can’t research and funding make it available very soon? It seems that a large scale validation of both a coal power plant with algae system to absorb carbon dioxide in Powder River Basin is of highest urgency. How much would it then cost to build transmission link to East or West grid versus load coal into railcars for transport to existing power plants?

  2. Wessel Roux says:

    We developed a technology to extract ethanol from any green waste, not just switchgrass etc. We also built a demonstration plant to prove the process. Our problem in South Africa is to access funding to build a larger scale plant.
    We believe our system can have an enormous impact on the ethanol market as well as garden waste reduction at landfill sites.
    Oh yes, I forgot to add that one of the by-products is compost that will help grow more feedstock. Is that a renewable cycle or what
    Wessel Roux
    Morangaphanda Technologies
    Our website will be up by the weekend

  3. Zinedine says:

    Algae has the benefit of the mass which is starch and sugar. Then there is also the oil. Therefore you can make the algae biodiesel and also the ethanol. This is the best of both worlds.

  4. Prrof. Hans-Jürgen Franke - Aracaju-SE says:


    University of Hawai’i Professor Pengchen “Patrick” Fu developed an innovative technology, to produce high amounts of ethanol with modified cyanobacterias, as a new feedstock for ethanol, without entering in conflict with the food and feed-production .

    Fu has developed strains of cyanobacteria — one of the components of pond scum — that feed on atmospheric carbon dioxide, and produce ethanol as a waste product.

    He has done it both in his laboratory under fluorescent light and with sunlight on the roof of his building. Sunlight works better, he said.

    It has a lot of appeal and potential. Turning waste into something useful is a good thing. And the blue-green-algae needs only sun and wast- recycled from the sugar-cane-industry, to grow and to produce directly more and more ethanol. With this solution, the sugarcane-based ethanol-industry in Brazil and other tropical regions will get a second way, to produce more biocombustible for the worldmarket.

    The technique may need adjusting to increase how much ethanol it yields, but it may be a new technology-challenge in the near future.

    The process was patented by Fu and UH in January, but there’s still plenty of work to do to bring it to a commercial level. The team of Fu foundet just the start-up LA WAHIE BIOTECH INC. with headquarter in Hawaii and branch-office in Brazil.


    Fu figures his team is two to three years from being able to build a full-scale
    ethanol plant, and they are looking for investors or industry-partners (jointventure).

    He is fine-tuning his research to find different strains of blue-green algae that will produce even more ethanol, and that are more tolerant of high levels of ethanol. The system permits, to “harvest” continuously ethanol – using a membrane-system- and to pump than the blue-green-algae-solution in the Photo-Bio-Reactor again.

    Fu started out in chemical engineering, and then began the study of biology. He has studied in China, Australia, Japan and the United States, and came to UH in 2002 after a stint as scientist for a private company in California.

    He is working also with NASA on the potential of cyanobacteria in future lunar and Mars colonization, and is also proceeding to take his ethanol technology into the marketplace. A business plan using his system, under the name La Wahie Biotech, won third place — and a $5,000 award — in the Business Plan Competition at UH’s Shidler College of Business.

    The production of ethanol for fuel is one of the nation’s and the world’s major initiatives, partly because its production takes as much carbon out of the atmosphere as it dumps into the atmosphere. That’s different from fossil fuels such as oil and coal, which take stored carbon out of the ground and release it into the atmosphere, for a net increase in greenhouse gas.
    Most current and planned ethanol production methods depend on farming, and in the case of corn and sugar, take food crops and divert them into energy.

    Fu said crop-based ethanol production is slow and resource-costly. He decided to work with cyanobacteria, some of which convert sunlight and carbon dioxide into their own food and release oxygen as a waste product.

    Other scientists also are researching using cyanobacteria to make ethanol, using different strains, but Fu’s technique is unique, he said. He inserted genetic material into one type of freshwater cyanobacterium, causing it to produce ethanol as its waste product. It works, and is an amazingly efficient system.

    The technology is fairly simple. It involves a photobioreactor, which is a
    fancy term for a clear glass or plastic container full of something alive, in which light promotes a biological reaction. Carbon dioxide gas is bubbled through the green mixture of water and cyanobacteria. The liquid is then passed through a specialized membrane that removes the ethanol, allowing the water, nutrients and cyanobacteria to return to the photobioreactor.

    Solar energy drives the conversion of the carbon dioxide into ethanol. The partner of Prof. Fu in Brazil in the branch-office of La Wahie Biotech Inc. in Aracaju – Prof. Hans-Jürgen Franke – is developing a low-cost photo-bio-reactor-system. Prof. Franke want´s soon creat a pilot-project with Prof. Fu in Brazil.

    The benefit over other techniques of producing ethanol is that this is simple and quick—taking days rather than the months required to grow crops that can be converted to ethanol.

    La Wahie Biotech Inc. believes it can be done for significantly less than the cost of gasoline and also less than the cost of ethanol produced through conventional methods.

    Also, this system is not a net producer of carbon dioxide: Carbon dioxide released into the environment when ethanol is burned has been withdrawn from the environment during ethanol production. To get the carbon dioxide it needs, the system could even pull the gas out of the emissions of power plants or other carbon dioxide producers. That would prevent carbon dioxide release into the atmosphere, where it has been implicated as a major cause of global warming.

    Honolulo – Hawaii/USA and Aracaju – Sergipe/Brasil – 23/10/2008

    Prof. Pengcheng Fu – E-Mail:
    Prof. Hans-Jürgen Franke – E-Mail:

    Telefon: 00-55-79-3243-2209

  5. i am sam says:

    This is redundant, and against everything the scientific people stand for.

  6. Alternative energy sources are imperative to the sustainability of our economies future! Please come and visit Valcent to see what we’re doing in efforts to promote algae biofuel. Come and see our commercial sized unit producing algae and turning into a valuable alternative energy source!
    Jessica Brock

  7. harold says:

    There is no mention of the heating value for the ethenol or bio diesel. Shouldn’t we be comparing these vaiues to gasoline? The is no mention of the energy balance for making either ethenol or bio diesel. I would think you could get a positive energy balance from algea or kelp

  1. [...] a good comparison of algae biofuel vs cellulose ethanol at EcoWorld that was just posted today.. Algae isn’t nearly as developed as cellulose ethanol but in my [...]

  2. [...] the title of this post, it isn’t an either/or choice, and comparing the potential of algae versus cellulose as a biofuel feedstock is an interesting [...]

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