Your Car Runs On Pond Scum!

Anyone who has walked along the edge of a common pond has probably looked into it and said, “What a bunch of pond scum, there is nothing good about that!” Well times have changed. Pond Scum may be the future of Alternative Fuel. A highly renewable source that does not take anything from our food sources, like corn or soy.

What is Pond Scum? The better name for it would be Algae. There are over 100,000 different species of plantlike organisms that belong to the algae family. They come in come in many colors, red, green, and brown are the most common. Sizes range from microscopic protozoa floating in ponds, to the grassy looking stuff that grows on rocks and other plants, all the way up to the large bunches of seaweed that you see in the ocean. Algae can grow in sea water, fresh water, even contaminated water. Algae are easy to please, all they need are water, sunlight, and carbon dioxide. They multiple faster than any other microorganism, 10% - 15% faster than any land based plant.

What makes Algae an alternative fuel source?

50% of algae’s weight is oil. That lipid oil can be used to make biodiesel for cars, trucks and airplanes. With so many types of algae available to research, some companies and research facilities are trying to figure out which species are good for each type of fuel. Algae are not picky eaters, but certain environmental conditions can create a more efficient fuel source. Because algae are tiny little biological factories that use photosynthesis to transform carbon dioxide and sunlight into energy so efficiently, conditions need to be highly controlled.

As part of the photosynthesis process algae produce oil that can generate 15 times more oil per acre than other plants used for Bio-fuel, such as corn, soy, and switchgrass. The yields can be more than 10- 100 times more than competing crops. Scientist have a theory that if algae is fed extra carbon dioxide and organic material like sewage, they will multiple even faster. An added advantage would be the cleanup of greenhouse gasses and contamination, solving other eco-problems in the course. So, in the world of alternative fuels, there can be nothing “greener” than pond scum!

How is the oil extracted from the Algae?

It’s kind of like juicing any kind of fruit or vegetable, with an additional chemical reaction added. There are a few different ways to extract the oil from algae. The oil press is the simplest and most popular method. It's similar to the concept of the olive press. It can extract up to 75 percent of the oil from the algae being pressed.

Basically a two-part process, the hexane solvent method (combined with pressing the algae) extracts up to 95 percent of oil from algae. First, the press squeezes out the oil. Then, leftover algae is mixed with hexane, filtered and cleaned so there's no chemical left in the oil.

The supercritical fluids method extracts up to 100 percent of the oil from algae. Carbon dioxide acts as the supercritical fluid -- when a substance is pressurized and heated to change its composition into a liquid as well as a gas. At this point, carbon dioxide is mixed with the algae. When they're combined, the carbon dioxide turns the algae completely into oil. The additional equipment and work make this method a less popular option.

Once the oil's extracted, its refined using fatty acid chains in a process called transesterification. Here, a catalyst such as sodium hydroxide is mixed in with an alcohol such as methanol. This creates a biodiesel fuel combined with a glycerol. The mixture is refined to remove the glycerol. The final product is algae biodiesel fuel.

Can enough be made to make a difference to our consumption of fossil fuels?

Several companies are already in the works for mass production. Grants are being issued to scientist who can come up with new ways to cultivate in different conditions. A company in Texas, Valcent Products, are growing algae in a patented system called Vertigo. Using a series of long rows of moving, plastic bags, they use sunlight to power their facility as well as its use in the growing process. By going vertical, they can expose more cells to the sunlight, moving things enough to keep a constant exposure to sunlight to ensure photosynthesis. This facility can produce more than 100,000 gallons a year, per acre, of algae oil, or “oilgae”, “algal fuel”, or “algeaoleum,” compared to 30 gallons per acre from corn, and 50 gallons from soybeans.

Who would think of Pond Scum as fuel?

Well, actually this concept has been around for many years, the 1950’s to be exact. The U.S. Department of Energy did pioneering research on it from 1978 to 1996. But, in 1996, The DOE’s National Renewable Energy Lab, decided that algae oil could never compete economically with fossil fuels. That was when the price of a barrel of oil was about $20. Move ahead to present day, oil is at about $75 dollars a barrel, and could be as high as $88 by the end of the year. Algae is looking a lot better now.

The Texas based plant, Valcent Products with their Vertigo system, and San Francisco based Solazyme are fronting the research and development. Other companies are being funded by Big Oil companies, and are running research through Universities across the country.

Solazyme is working with some interesting concepts. Soladiesel, the first of Solazyme’s planned algal fuel projects, is a biodiesel produced from algae that are engineered to produce oil with an optimized fatty acid profile to enhance cold flow performance, among other properties, and are also modified to grow in the dark in industrial fermentation tanks fed with plant sugars. The focus on scale and production economics was one of the drivers to modify algae to grow in the dark in fermentation tanks, sustained by sugar, rather than photosynthetically in the open. Growing conventional, photosynthetic algae in the open requires dealing with the variability of the environment, light limitations and contamination with microbes. The scientists found that by inserting just one gene that catalyzes glucose transport into the diatom Phaeodactylum tricornutum, the organism could thrive in the dark, getting its energy exclusively from the glucose. This marked an important first step toward large-scale, high-density, cost effective cultivation of algae using fermentation technology.

Solazyme has another two or three years of work until it is at production economics, defined as parity with fossil fuels. Solazyme recently entered into a biodiesel feedstock development and testing agreement with Chevron Technology Ventures, a division of Chevron USA, in the shorter term is also working on developing algae optimized to produce oils for use in hydrotreatment a refinery. Solazyme has also received funding from NIST (National Institute of Standards and Technology) to support a project to use algae to produce biopetroleum, which will match the composition of sweet light crude oil. The biopetroleum would be fully compatible with the infastructer that refines, distributes retails, and consumes petroleum products, working toward developing Aviation fuel as well as other chemical applications. The NIST funding is expected to accelerate the project by four years.

O.K, so it’s possible, Give me the numbers!

Given the right conditions, algae can double its volume overnight. Microalgae are the earth's most productive plants - 10 to 15 times more prolific in biomass than the fastest growing land plant exploited for biofuel production. While soy produces some 50 gallons of oil per acre per year; canola, 150 gallons; and palm, 650 gallons, algae can produce up to 15,000 gallons per acre per year. In addition, up to 50 percent of biomass for some microalgae is comprised of oil, whereas oil-palm trees - currently the most efficient large-scale source of feedstock oil to make biofuels - yield approximately 20 percent of their weight in oil.

The following table gives some typical yields in US gallons of biodiesel per acre
Plant Yield of Biodiesel(gallons per acre)

Algae - 5000 and higher
Chinese tallow  - 500-1000
Palm oil - 500
Coconut  - 230
Grapeseed - 100
Soy - 60-100
Peanut - 90
Sunflower - 80-100

Oil from microalgae can easily be converted to biofuels such as biodiesel through the same technology used with oil from oil seeds which is currently used to convert vegetable oil to biodiesel (transesterification is the main conversion process). In addition, it is possible to hydro-treat the algae oil to produce other fuels such as JP-8 and other jet fuels.

Thank you to all of these fascinating articles for source material for this article.

http://www.cnn.com/2008/TECH/science/04/01/algae.oil/index.html

http://www.oilgae.com/ref/report/report.html

http://www.enn.com/energy/article/37961

http://science.howstuffworks.com/algae-biodiesel.htm

http://algaebiodieselfuel.org/category/algae-oil-101/

http://www.greencarcongress.com/2008/02/solazyme-ups-so.html