Wearing their Thinking Caps: A New Algae to Ethanol Process

Scientists at the Department of Energy’s National Renewable Energy Laboratory (NREL) have released a study that unveils a new process for producing ethanol from algae. The process, named Combined Algal Processing (CAP), promises to be more effective and affordable. It was published in the Algal Research journal by authors Tao Dong, Eric Knowshaug, Ryan Davis, Lieve Laurens, Stefanie Van Wychen, Philip Pienkos and Nick Nagle.

In work the set the stage for the published study, NREL researchers produced ethanol not just from lipids (the traditional components used to make fuels from algae) but separated out carbohydrates and proteins as well, both of which can be converted into fuel products. While this reduced the cost of increasing the amount of lipids in algae, a large chunk of the carbohydrate sugars were lost when the researchers used a solid-liquid separation process to isolate the carbohydrates.

Fast forward to the current study. The researchers skipped the solid-liquid separation process and exposed all algae components (lipids, carbohydrates and proteins) to the fermentation process. This resulted in a 32 percent greater yield than with lipids alone. The costs were also successfully reduced. Albeit not yet competitive with petroleum, it is a major step in the right direction.

For more information about the study, visit the NREL website.