Plants are the undisputed champions of solar power. After billions of years of evolution, most of them operate at nearly 100 percent quantum efficiency, meaning that for every photon of sunlight a plant captures, it produces an equal number of electrons. Converting even a fraction of this into electricity would improve upon the efficiency seen with solar panels, which generally operate at efficiency levels between 12 and 17 percent.
Maybe the previously stated efficiencies for plants were calculated when extracting sugars? This process tries to capture the electrons before sugar is made. Obviously the 'quantum efficiency' isn't what they'll harvest, but I would think they could get a reasonably large percentage.
While the overall efficiency of this system is yet to be determined, it probably has a much lower embedded energy (i.e. the energy that went into producing it) than PV. This system seems to use a carbon-nanotube backing, no silicon in it.
Also, how many PV panels reproduce? (Answer: none that I'd want.)