My wind generator has 'bit the gust' temporarily.
Today (19.01.07) in the U.K we had a rare freak wind of up to 80 mph that had a detrimental effect on the 100w wind generator .
The generator and blades were working well and producing 5 amps of current into the 12v battery (60 Watts of power). The problem that caused the wind generator to crash to the ground was the guy ropes. They were made from 8mm polypropylene rope, which I have recently found out degrades due to U.V light. The savage gusts put a huge strain on the guy ropes and one of the four ropes failed causing the tower to fall to the ground.
You can notice how the broken blade 'speared' itself into the ground 6" deep. I estimate that it was spinning at approximately 900 rpm when it fell. No real harm done, the motor/generator still works ok.
Back up and running 27-01-07
I just needed to make some new blades and buy some steel guy cable's, a cheap source are the plastic covered steel washing line cables.
The 20 meters I required cost me just £3.36
I am using the smaller diameter 36" aluminium blades at the moment. These blades like the P.V.C type that broke don't have the proper aerofoil section that gives the correct 'lift', but still work admirably. The ultimate option is to carve wooden blades with the correct geometry.
Hugh Piggott has a good 4Ft diameter wooden design propeller design in his "How to build a wind turbine" book. Ands costs just £11 (U.K)