A Wired article (thanks Mike!) that got me thinking about how much of crude oil’s energy is geologic, rather than photosynthetic.  Upon deposition of biogenic sediments, there is tectonic transport, geothermal heating, and compression in subduction zones or beneath additional deposits.  How to account for these energetic contributions?

Also, the researchers’ general approach seems sort of sloppy.  A good terrestrial farmer would harvest a crop (of plants), mechanically process it into products, and compost/recycle the “waste.”  Here the crop of algae appears to be simply cooked en mass (including with water) into crude with little analysis of how distillation or cracking would generate products from the resultant soup.  Given that we have the option of processing the crop before cooking it (which was long-missed for fossil fuels), is it more efficient to process before attempting thermo-baro-chemical transformations, or to crack apart the goo once cooked?