I'm not sure it would ever pay for itself. Plus the reduced air flow due to more fiction on the wind turbines might keep more heat in the attic longer, off setting the power savings. I have seen some pretty cool vertical wind turbines, but the general rule of thumb (heard from several turbine guys) 12mph of wind= 100 watts of power. The math just doesn't add up in my eyes. I looked into buying the cheap ebay micro turbines but they just won't make enough power to be worth the trouble.
Either buy a good sized turbine and mount it as high as you can, or spend the money on solar.
Just my 2 cents
__________________
שְׁמַע יִשְׂרָאֵל ה' אֱלֹהֵינוּ ה' אֶחָד
|