The interesting thing about the tube growing algae was:
- the capture and reuse of water (no evap...just condensation)
- vertical growth reduced acreage requirements
With that being said, the devil is in the details. It is not cheap to extract oil and you need phosphorus / phosphates to grow it. With the looming phosphate shortage...well maybe bio fuels is not a very good option unless we can recycle the phosphate...essentially feed the algae back to itself after extracting the oil?
Growing algae under controlled conditions is very hard. I did some research while in skool, which involved trying to grow Microcystis to yield some toxic metabolic by-products that can kill fish. Massive fail because we didn’t include some micronutrients in the medium.
I can’t imagine the enormous scale required to make sufficient gasoline, er ethanol? from algae. Just what kind of yield of fuel per ton of algae are they expecting? How much energy and labor will it take?
No doubt such a system could demo the technology, but it sounds cost prohibitive to construct such a large facility. I wonder also about the maintenance of such equipment. I had not even considered yet the issue of nutrients such as phosphates. Harvesting the oil is taking something out of a closed system, and therefore it seems that nutrients would have to be replenished from an external source to some extent.
I think basic research should continue, but I can’t see anything practical happening for a long time.