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Mod: We'll move to the next question from Ken in Canada (19:10)
Q. What is the most effective and economical oil extraction method?

Carel: Mark, do you have any idea?

Mark: Yes, it's one of these million dollar questions, the answer is it really depends on the species you're using. There's hundreds of thousands of different kinds of algae with different oil contents, and also with different physical characteristics. And the physical characteristics will determine how easy or how difficult it is to get the contents in general out. Not just the oil, but the contents in general. Typical green algae have have a cellulosic cell coverage, which makes it quite difficult to get the contents out. Because it's quite robust, it's a bit like a stress-ball, if you want to. If you push it, it will go in all kinds of directions, but if you release the tension it will go back to its normal shape. So you would need different kinds of technologies, and a lot of work is being done in that area currently, with a lot of different technologies, even going as far as using magnetic fields and ultrasonic technologies and so on.

At SBAE we don't need any of those, because of the work we do with diatoms. Diatoms have silica cell enclosures, and silica cell enclosures have the big advantage that they can be opened using standard technology. Standard mechanical pressure... because of the physical characteristics of the cell covering.

Carel: Yes, with green algae or with other algae, some have a thick cellulosic membrane, some have a thinner one, and indeed it depends on how you grow them, how you stress them, if you use enough sheer, then I think that's a competitive edge that companies will achieve by themselves under the conditions that they have, and the local conditions, how they can get the oil out. So I think that is a multi-million question there, and I don't think many people, when they figure it out, it will be published very quickly. People will use it for themselves I think. At least that's what we do.

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In this particular case we actually take that algae, and rather than harvesting it directly, we... actually have brine shrimp harvest it. We have brine shrimp eat that algae, and the reason we do that is, these are some of the original harvesters of algae developed through evolution. They're very good at it, they do it with a huge amount of energy efficiency, and they convert about 50% of the algae they eat into their own biomass.

So here we have half that weight, 270 Kg of shrimp. But we take the shrimp, which are easy to get out of water, and these are brine shrimp, they're only about 1 cm long, we take those shrimp, and we can get them out of the water through screening and divide them into representative products such as oil, which can be converted into biofuels, into animal protein which is really a very valuable product. Chitin, which is exoskeleton, and then we can take the brine shrimp poop, actually, and move it up here (into an anaerobic digester), mix it with a little extra carbon, which could be sawdust or corn husks, or any of those, and through anaerobic digestion turn it into methane and fertilizer.