--- Nick > but wouldn't it be simpler to use a > pyrolysing/gasification process to turn > the cellulose into syngas?
Simpler yes, and it would be a lower initial investment... perhaps it is a good way to start-out, but significant CO2 is produced; whereas with the aqua-gen type of conversion, almost none. CO2 at that stage also reduces the energy content available for sale as a liquid fuel. I don't know which way would result in the most cost effective solution, or best ROI - probably the pyrolysis since it is simpler and relatively cheap, but it would be significantly less "green" (ecologically desirable). If a good basic windmill design could ever be standardized (perhaps world-wide) and then mass-produced to achieve rock-bottom cost, then it would make a stronger case for many situations. Jones