Photanol
Both first-generation and second-generation biofuel pro-
duction technologies consist essentially of two phases. First, solar energy drives synthesis of highly complex molecules (cell constituents) and structures (cells and plants) from CO2. In the second phase a (small) fraction of these complex products are converted to small mol- ecules (like ethanol) in the case of plants, or are extracted and converted chemically to fatty acid-methyl esters in the case of algae. Thus, much of the light energy is lost in nonfermentable waste (but see e.g. [8]) and both pro- cesses contain numerous steps, each with its typical efficiency, which leads to low overall efficiencies. Sec- ond, both processes are limited by the capacity of the phototrophs to intracellularly store the substrates to be fermented or extracted. A third disadvantage is the fact that these technologies cannot be carried out in a con- tinuous process design.