Algae for Green-Bio-Fuels

By: Dr. John Kyndt – Head Scientist of the Renewable Energy Program at Advanced Energy Creations Lab .

Although algae have been thought of as a potential fuel source in the past, it wasn’t until the skyrocketing fossil fuel prices in 2008 that this miniscule source of power was taken seriously. Previously mainly known as “pond scum” and a plague for pool owners and fish farms, algae are now being seen as a promising and emerging investment for future energy sources.

Algae for Green-Bio-FuelsIn the last two years there have been announcements of million dollar investments from both private and government sources into the algae for fuel concept.

Think for example of the Exxon-Mobile announcement of a $600 million investment in algae biofuels, and the recent DOE funding of the National Alliance on Advanced Biofuels and Bioproducts (NAABB) to perform algae-derived fuel research.

With all these million dollar investments and with even the world’s largest airplane maker, Boeing, turning its eyes on algae, it is clear that the race to develop the next generation fuel from algae is on.

The concept of using algae for fuel is remarkably simple. The fuel is essentially derived from algae that have captured energy through the photosynthesis of sunlight while growing in nutrient-rich water sources such as sewage ponds. The algae use the energy to create biomass, while capturing carbon dioxide.

Algae need in average 2.8 tons of CO2, 0.95 ton of nutrients, light and water to produce 1 tons of dry matter. The resulting biomass can be used for fuel production by a few possible pathways.

Depending on the biomass composition, it can be used to produce biodiesel (through transesterification), biojetfuel (through hydrocracking), or bioethanol (through fermentation). The biomass composition is dependent on the algae species grown. Some species have a high preference for lipids as storage material (40-70 % of the dry weight) and others become rich in carbohydrates (starch and sugars).

The lipid-rich algae are an excellent source for biodiesel and petrol production, while the high-starch species are ideal candidates for the production of bioethanol. By controlling the supply of certain environmental factors, algae can be tuned to produce unusually high quantities of lipids or starch.

Compared with terrestrial crops, microalgae are inherently more efficient solar collectors, use less land, and can double their mass in about 3-4 hours during optimal growth, which is significantly faster than the doubling time for other plants that are used for bioethanol or biodiesel production (e.g. corn and switchgrass for ethanol and palm oil). One major advantage is that algae are lacking cellulose which simplifies the biomass to liquid fuel conversion.

Although the concept is very promising and the stakes are high, there are still major challenges to overcome, hence the need for million dollar investments.

One challenge is the fact that the slower growing algae species make the higher concentrations of lipids and/or carbohydrates, while the faster growing species don’t. Another is the lack of economically viable harvesting technologies for large scale algae production. Current efforts are being focused to create algae with improved traits and to develop innovative harvesting technologies.

We are utilizing state-of-the-art proteomics and cutting-edge genetic engineering to tackle these issues because we sincerely believe that biofuel from microalgae is a renewable biofuel that has the potential to displace petroleum-derived transport fuels without adversely affecting supply of food and other crop products.

7 comments

Comments are closed.