It is likely that ,while a truss would be lighter and stronger, to counteract the forces encountered by a turbine it would also require a cross section so large, as to interfere with the blade travel, rendering the proposal, impossible. There are small wind turbines useing truss style towers, but they all have a "stub" tower on top, and they are under 10kw......10-15'blades. the wooden tower under discussion, is also "small" by todays standards, and unlike steel towers that can be made by any half respecting medium sized fabricator, will require a specialised industrial facility that cant make anything else usefull, and so the one that is doing this, is funded at great expense from government grant funding. kinda cool,kinda cringe