Oil From Algae

If you think of algae only in terms of it being a green slime that mucks up ponds and neglected swimming pools, think again. The ability to get oil from algae makes it a very promising source of alternative energy. Read on to find out why getting energy from algae is so promising.

Algae use photosynthesis to capture solar energy. As with plants, the photosynthesis process drives biochemical reactions that convert CO2 and water to carbohydrates that fuel plant growth.

Several characteristics of deriving oil from algae make it appealing as an energy source.

For one thing, algae grows rapidly. If conditions are right, it can double in 24 hours. That means half the biomass can be harvested every day indefinitely.

Furthermore, algae contain up to 50% oil by body weight. This is far more than any other plant source. To put this in perspective, consider that canola yields about 150 gallons of oil per acre per year while the potential yield of algae from one acre is 10,000 gallons!

In addition, algae also contain carbohydrates that could be converted into ethanol.

As a further bonus, algae require high levels of CO2 to reproduce and grow rapidly. Theoretically, CO2 emissions from a fuel-burning power plant or other CO2 emitter could be used to support algae growth, thereby preventing the release of carbon dioxide into the atmosphere.

In fact, an oil-from-algae start-up (Solix) is building a demonstration project that uses the CO2 emissions from the fermenting process at a brewery to support the growth of algae.

I think you can see why the potential of algae is so alluring. However there are some difficulties (I bet you guessed that).For one thing, algae are somewhat finicky. To get those kinds of yields conditions have to be just right.

Also, there over 100,000 species of algae and it’s not clear which ones are the best for this purpose. It’s likely that different species will be needed in different environments.

Although the challenges are real, so are the potential benefits. To give you some idea of the potential, the entire US demand for diesel could be met by algae grown on ½ of 1% of the acreage currently under cultivation. Compare that to ethanol from corn. Using all arable land in the US to produce ethanol from corn might meet 15% of energy needs at huge costs. (For more on the drawbacks of ethanol from corn as a source of biomass energy see: Ethanol as Fuel )

Also, algae can grow in areas not suitable for agriculture, such as the desert Southwest.

The potential for oil from algae is real and very exciting. It will very likely be part of our energy answer. I think you’ve noticed that a common theme on this site is that there is no one best alternative energy answer. Rather, the best answer will be multifaceted – energy from a wide variety of sources we’re only beginning to explore and some that haven’t even been dreamed of yet.

Because human ingenuity is unlimited, so is our energy potential.


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