The strange case of algal biofuels

Your's is one of the most accurate algae oil articles I have read - out of hundreds. I write from the authority and experience of producing algae commercially for about 40 years - but not for fuel. I like your energy budget approach - something algae oil fuel promoters have avoided like the plague. Understandably since energy budgets show as you point out - a complete lack of technical feasibility in current technologies - not just in producing the algae, but in the complete complex process of producing fuels from algae. You could also take it to a more investor friendly - economic feasibility analysis, but of course the results would be even worse for current algae oil production technologies. It just isn't anywhere near economically efficient or feasible. We estimate that current algae oil production technology is at best is 9 times the costs of equivalent petroleum products - perhaps even more. Current algae oil is even two to three times more expensive per gallon than vegetable oil.

When you see algae oil developers focusing on, and giving information on - their production costs per gallon of salable fuels (rather than yields of oil per unit area) then you know a competitive algae fuel production technology is at hand. To some what paraphrase your conclusion, the algae oil developers could use a lot less PR people and a lot more economist. The challenge in algae based fuel development isn't limited technology - it's limited economic understanding by the would be algae oil developers and especially their eager, but naive investors.

A very important article. Indeed, as with all other biofuels, a full energy-cost analysis is needed for algal biofuel. I have pointed out on scitizen previously that there is a further issue of the nutrients that are needed, principally phosphate, to grown algae and indeed all other crops.

Thus algal biofuel is subject to the same potential limitations that agriculture is in general, since the world peaked in rock phosphate production 20 years ago. To proceed in this endeavour and in agriculture in general it will become necessary to recycle N and P from animal and human waste and biochar may help as a soil amending agent that causes the soil to hold fertilizers more firmly than in its absence, thus requiring less of them to be applied in the first place.

I am also puzzled about the viscosity problem of "biodiesel" derived from algae or from other plant oil, when a plane is flying in the frigid conditions of the troposphere. At -50 deg. C thus material would become too thick to pump, unless the fuel tanks are kept warm.

It is possible to crack such oil into hydrocarbons but of course the process then becomes more complex and energy intensive, not to mention the extra engineering necessary and on a stupendous scale.

I like very much the idea of algal biofuels but it seems to me that a solution to petroleum depletion is not thus provided as yet by them. We get through 30 billion barrels of crude oil a year and about 85% of that is used for fuel, and 65% of it for transportation.

Chris Rhodes.

With respect to the interest by airlines--you are correct in stating that biofuels as currently produced would not be able to meet "freeze-point" specifications for airline fuels. I assume they are banking on the substitution and utilization of more biofuels at ground level, allowing refiners to increase the severity of their Hydrocracker operations from the "maximum diesel" mode to the "maximum jet fuel" mode.

With respect to algae produced biofuels, I am also concerned about "electricity" and/or "cooling" requirements not being fully included in the balances and estimates. Photosynthesis is, at best, 5% efficient, meaning 95% of the incoming solar must be removed as "waste heat'. The only device of accomplishing this removal efficiently (while producing electricity) is the Atmospheric Vortex Engine, which can do this on a "dry" basis using heat exchange with the atmosphere, in locations where evaporation of water from the process is a concern (i.e., any arid region).

Bottom Line: The AVE (http://vortexengine,ca) would be a necessary companion technology for the production of liquid fuels from ANY source, if this is to be accomplished effectively and economically.