Bioreactor helps bridge the gap for algae-based biofuels

Researchers at Michigan State University (MSU) have invented the environmental photobioreactor (ePBR) - a system to grow and test algae for potential use as biofuel. Many scientists are already looking for strains of algae that could become a sustainable source of energy, but those strains that perform well in labs often fail when it comes to scaling up the experiment.

“Algae in natural or production setting experience fluctuating environmental conditions including changes in light, temperature, CO₂ and nutrient availability, oxygen and mixing,” said the team in the journal Algal Research. “In response, algae respond to environmental changes dynamically, adjusting light energy capture strategies, physiological processes and cell cycle control.

“In contrast, much algal research is performed under artificially static laboratory environments, where different constraints determine performance. Consequently, algal strains selected for mass production in the laboratory may fail to perform well or outcompete local algal strains under outdoor production conditions.”

As MSU research associate Ben Lucker puts it, “It’s like training elementary kids to be really good ping pong players, but then they take the kids and throw them into a football game against professional players. In those settings, they simply can’t compete at all.”

The ePBR was the brainchild of David Kramer, Hannah Distinguished Professor of Biochemistry and Molecular Biology at MSU, whose work was funded in part by the US Department of Energy and MSU AgBioResearch. It is effectively a pond in a jar, about the size of a coffee maker, which helps identify, cultivate and test algal strains that have the potential to make the leap from lab to pond, where they will proliferate in real-world settings.

The system does this by simulating dynamic natural environments, “[mimicking] lighting from natural pond environments while controlling key environmental parameters including temperature, pH and CO₂ levels, mixing and culture density”, said the researchers. By allowing scientists to duplicate natural settings in a lab, the ePBR eliminates variables before scaling up.

The system also can duplicate and confirm results from experiments conducted anywhere in the world. It replaces home-built growing platforms made from flasks, tubing, aluminium foil and grow lights, and gives researchers a tool that can consistently replicate conditions and reproduce results, according to Lucker.

The ePBR is available for sale through MSU spin-off company Phenometrics.

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