Completely ignoring the original question, but this may be of peripheral interest. I made a small desk fan using a pair of EDF-55 fans with GWS motors and a 3s1p Li-Po pack. Well, I say small, but it was enough to clear my desk, and most of the floor of any loose paper. I blew the 2A fuse when I ramped it straight up to full power rather than a slow start, so I replaced that with a 5A fuse (sorry Gert! I didn't have a 4A to hand). I stopped using it in the end when I noticed how hot the motor controller was getting, and that combined with the unrecommended fuse made me stop in the interests of preserving the Gertboard.
Good fun though. I also had it controlled from a DS18B20 temperature sensor, so when the temperature got above 22 degrees the fan automagically came on. This is, of course, spectacularly pointless in a shed where the most efficient form of heating is when I leave my soldering iron on for too long. Maybe next summer I'll resurrect the project.