Forbes on the economics of biofuel from algae
So instead, Wijffels is attempting to use algae to promote clumping. He has added flocculating strains of algae, such as Ankistrodesmus falcatus, to a reactor containing the oil-producing strain Chlorella vulgaris, and found the two types readily joined together in clumps.
“You can have co-cultures of microalgae, in which one of them is really good at oil accumulation and the other one is really good at sticking to the other algae,” he says. “The art, of course, is to have a large percentage of oil-producing algae and a very small percentage of those flocculating algae.”
To get a better insight into the financial and energy costs of production, Wijffels aims to test the technique at Wageningen University’s Algae Production and Research Centre. AlgaePARC was launched earlier this year and allows algae-production processes to be tested alongside each other under the same conditions. It is supported by companies including ExxonMobil, Total, and biologist Craig Venter’s firm Synthetic Genomics. It has an open pond and six outdoor bioreactors made from horizontal tubes, vertical tubes or flat panels.
Ultimately though, if algae biofuel is to be made financially and environmentally sustainable, we will need to make use of more than just the oil produced by the organisms, says Schlarb-Ridley, who authored a report earlier this year on research into algae for the UK’s Biotechnology and Biological Sciences Research Council.
“Even if you are able to produce algae on a mass scale, you still need to use the by-products as well as just the fuel,” she says. Fortunately, as well as being oil producers, algae are also a valuable source of protein for fish and animal feed.
In a similar way, algae can use the by-products of other industries, says Schlarb-Ridley. Algae reactors could be connected to farms or fisheries, to consume the nitrate-rich waste they produce. Algae can also mop up the CO2 from flue gases from nearby industrial plants.