Unfortunately, the algae energy industry is haunted by exaggeration and irrational excuberance. There is definately a potential within algae biofuel, but the overly optimistic views are not particularly helpful to create credibility for the industry.
One might ask how many photons per (acre-year) are needed to make 20,000 gallons of any biofuel? Perhaps, Jan-Hendrik is alive and well and in Cambridge? For some background on issues, one might look at “Closed photobioreactors as tools for biofuel production ” Current Opinion in Biotechnology 2009, 20:280–285, which notes a photoconversion efficiency [PCE] of about 9%, and states: for reaching the ceiling of 9% PCE, photo-bioreactors have to be almost ideal concerning mass and light transfer. That is, of photosynthetically active photons in sunlight [PAR, 400-700 nm], only about 9% go into photosynthesis. Then, one must consider “how many” photons are needed per molecule of biofuel.
via IPBiz: Technology Review speaks of 20,000 gal/(acre year) biofuel production.
