I’m not sure if there are any independent studies on it, but the general consensus by Scientists worldwide (including many hundreds or thousands not involved in it) is that it will lower our overall CO2 output. For the moment, I think the Kyoto Protocol itself is the only study that can tell you how much it will reduce them by. But honestly, the CO2 output argument is a pretty moot point. We’ll be out of most fossil fuels LONG before we totally kill our planet.