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Co-location could make algae biofuels affordable

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SAN DIEGO—Researchers are continuing to develop strains of algae that yield a greater volume of oily compounds that can be processed into biofuels. But as more new and established companies examine how to scale up lab processes to commercial levels, scientists and engineers seem to be finding that standalone operations may not be economically viable. Co-locating algae farms with other industrial facilities could be one strategy that makes algal biofuels pay.

Typical algae strains use sunlight and water to convert carbon dioxide into lipids. Nutrients such as nitrogen and phosphorus can boost production, depending on the process. At prototype scales, supplying the "inputs" is not a problem, but at industrial scales, large quantities will be needed. Plentiful sources of CO2 and other nutrients are not readily available in many places, and even where they are, purchasing them at market prices could make algal biofuels too expensive.

The answer? Turn the waste from other industries into a resource for this new one, helping to solve the waste problem at the same time. With or without realizing it, various scientists speaking at the American Association for the Advancement of Science annual conference, which wraps up here today, were promoting the notion that algae operations should be located next to industries that can supply one or more of the nutrient streams.

For example, algae production facilities could be located next to coal-fired power plants, which happen to be under increasing pressure and regulation to reduce CO2 emissions. Instead of spending money to sequester that carbon, say, underground, why not sell it, cheap, to an adjacent algae facility? Indeed, the Seambiotic algae plant in Tel Aviv, Israel, is tapping the flue gas of a coal plant next door.

Similarly, algae producers could locate near municipal wastewater treatment plants. "Cleansed" water that is usually deposited in rivers or other water bodies is generally safe for the environment, but still usually contains too much nitrogen or phosphorus for human consumption. Algae, however, thrive on those very compounds, and the alternative of purchasing them as fertilizer leaves a large environment footprint. Of course, the water itself is needed for algae production. A pilot plant run by Sunrise Ridge Algae in Austin, Tex., is piping in this resource from the Hornsby Bend wastewater plant there. Sunrise was hoping that enough CO2 could also be extracted from the wastewater, but the flow coming from Hornsby’s anaerobic digesters was inconsistent, not a big surprise since the system was not built to supply CO2, per se.

These integration concepts can be taken further, noted Norm Whitten, CEO at Sunrise. When the algae are harvested for their lipids, the remaining plant matter can be processed into animal feed, or converted into a syrupy liquid he calls bioleum that can be burned somewhat like oil, enhancing the economics of an algae biofuel plant. Whitten also noted that cement plants generate enormous quantities of CO2—about one ton for every ton of cement produced-which could be a nutrient stream for algae plants. And waste heat from cement or power plants could be used to warm algae ponds, bags or tubes to accelerate growth. Connecting all these dots, Whitten noted that the Route 35 corridor in Texas is home to many cement plants, which could supply CO2 and waste heat, and is also home to oil refineries, which could process the bioleum.

Whether such combinations will make algal biofuel commercially competitive remains to be seen, but it seems likely that co-location will be a big factor making a sizeable industry possible.

Photo of bottled algae from iStockPhoto/Rob Broek

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  1. 1. frgough 1:40 pm 02/22/2010

    Wow. CO2 as plant food. Imagine that! But, of course, putting plant food directly into the atmosphere will cause the end of all life on earth. Instead we must capture it and sell it so that we can directly apply it to a chosen target plant.

    Pure genius.

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  2. 2. ddugger 5:39 pm 02/22/2010

    You are way ahead of most of your peers in recognizing the problems of algae based biofuels. Most still haven’t figured out that any major energy contributions from algae will require chemical fertilizers to produce the algae. They haven’t figured out it’s those same fertilizers (that produce 85% of global human foods)… wait for it – come from petroleum. Consequently, as petroleum becomes more scarce and more expensive the cost of those crops necessarily rise with it. BSo, biofuels are always going to be dependent on petroleum and probably more expensive than the petroleum anthat their production is absolutely dependent on.

    Using waste nutrient sources to produce biofuels would seem to make economic sense. Unfortunately, those waste products are not where they need to be to use algae or other plants. You need consistent sunshine and you need lots and lots of space. Every non-biased study done on algae biofuel production has concluded that bioreactors are not cost effective – they simply use more energy than they produce. Beyond that in the 80 years that people have been trying to develop algae biofuels – bioreactors have never produced cost competitive energy. Actually, neither have open ponds, but pond costs are a lot closer to current petroleum costs. Basically – if any of my previous statements were incorrect we would running our cars on biofuel as we speak.

    Consequently, at scale algae production is going to need large surface areas. Current municipal sewage facilities were not located or designed to need this kind of space. To compound problematic municipal sewage facility location – over 35% of the nations sewage goes into septic tanks that are not cost efficient to collect from.

    CAFOs have concentrated nutrients, but the bulk of them are not located in high solar/high algae production potential areas. They tend to be in our seasonal grain belt areas. Algae needs to produce all year to have a remote chance of economic feasibility.

    If we have enough petroleum to last us until we can integrate algae production facilities and sewage facilities in to a new world order, then maybe something like 3% of energy needs will come from waste products. We are kidding ourselves with most biofuels that they only need sunshine and that we can make energy from nothing. Our alternative energy strategies need to be better grounded in the laws of thermodynamics with far better life cycle cost analysis.

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  3. 3. robert schmidt 12:52 pm 02/23/2010

    @frgough, it is truly amazing the depth and breadth of your ignorance. In just one paragraph you are able to communicate your lack of knowledge of both global climate change and economics. Obviously you have chosen not to believe the well established science that CO2 is a greenhouse gas. I guess it doesn’t feed into your paranoid delusions about science. Taking a waste product and turning it into a resource makes good economic sense but that also doesn’t fit your world view so you are incapable of understanding it. It must be tough living in the modern times when you have the mentality of a Stone Age simpleton. That you are able to use a computer, a product of the sciences you hate and fear, is astounding. You must have a helper monkey do the typing for you.

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  4. 4. kalmanson 12:25 pm 04/12/2010

    Lester Kalmanson Agengy, Inc leads the way in providing Aquaculture and Algae Insurance worldwide. Lester Kalmanson Agency, Inc understands the needs and requirements involved in insuring algae, whether seeking coverage for the stock – mortality / perils ( ie wind storms, hurricanes, tornadoes, extreme temperatures, bacteria, etc ) and / or liability for the algae farm(s). Coverage is offered for facilities both large and small, from 1+ acre ponds. Our policies are tailored and manuscripted for your operation(s) and / or activities. All policies underwritten by Lloyds of London.

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  5. 5. eco-steve 5:27 pm 04/12/2010

    This algal biomass process sounds too slow and complex to be economical. Methanisation via fermentation is slow too. Biomass Pyrolysis however is rapid, producing no pollutants and either hydrogen and biochar, biofuel or biogas. See for technical details and economic profitablity. This technique recieves liitle airing, although it is considered by such people as James Hansen as esential to avoid climate change.

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  6. 6. fatalgae 9:52 am 09/17/2010

    To learn about the fast-track commercialization of the algae production industry you may want to check out the National Algae Association, the trade association. The NAA engineering consortium has designed the first 100 acre algae production facility with all the CAPEX and OPEX.

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