Green power from green algea

As biofuel production using corn and sugar is criticised for putting food stocks at risk, could oil from algae solve the energy crisis?

Has a sewage farm just outside the New Zealand city of Blenheim provided a solution to the world’s energy shortages? Aquaflow Bionomic Corporation, a local start-up, has patented a process to extract biofuel from sewage, and last year the country’s minister for energy, David Parker, roadtested a car run on the oil of microscopic algae.

“Wild algae is one of the ubiquitous units of nature,” says Nick Gerritsen, a partner in the firm. “If you leave a bucket of water outside, the water will turn green as it is settled by wild algae. We realised very early that we needed to create a model that took advantage of wild algae feedstocks.”

The challenge was to catch what he calls “the little blighters”, the algae that contain oils or lipids, in the work’s outflow pipe, a cleansing process known as bio-remediation. In May 2006, the company produced what it claimed was “the first biodiesel crude from wild algae”. The process is secret, although oil was extracted from algae that had been separated from water, which Aquaflow wants to leave clean enough to drink.

Self-sufficient

Aquaflow first had to pass the energy balance test, creating a fuel that produced at least as much energy as went into creating it. The company went from pond scum to biodiesel in just over a year and says its fuel is suitable for domestic use and transport. Furthermore, it claims its technology fits “on the back of a truck”, and is cheap enough to be adopted anywhere. “Our aim is to enable communities to use their wild algae feedstock and become as self-sufficient as they can,” says Gerritsen.

Faith in algae to provide energy has spread. Last month, Shell announced it had formed a joint venture with HR Biopetroleum that will construct a demonstration plant to harvest algae they claim can double their mass several times a day, providing 15 times more oil per hectare than alternatives such as rape.

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