I just updated the article about solar attic fans at the main site withall the latest info plus an installation video.
Aside from being an effective method to reduce home cooling costs, easy to install, and costing nothing to run, the rebates and tax incentives are pretty liberal - especially if you live in certain states and municipalities.
Here's the latest on what's available:
The Federal Tax Credit for solar attic fans has been extended through 2016. The solar powered attic fan is eligible for a 30% (up to $1,500) credit on the purchase price of the fan, installation and sales tax.
Additional rebates of up to $100 are also available from local municipalities in the following states: California, Hawaii, Illinois, Indiana (entire state), Iowa, Montana, and North Carolina.
So let's say you bought a 10 watt solar attic fan that cools up to 1,200 sq ft of attic space for $286. After the 30% federal tax credit ($86) your cost is $200. After the $100 local rebate, if available in your area, your final cost is a measly $100 for something that could reduce your central AC portion of your electric bill by 15%.