Kallog
the below link is to a actual electricity company bill where the customer uses net metering , he uses a total of
1,568 kWh for the month and is charged $124.68 @ .08 cents
per kWh for his usage.
his solar pannel system sent 187 kWh to the power company
durring the month and he was credited $32.54 @ .174 cents per kWh.
his final cost was $103.70
judging from his credit amount of 187 kWh's he only has a
750 - 1000 watt system.
750 watts x 8 hours x 31 days = 186,000 watt hours
or 186 kWh
http://www.gasolar.org/uploads/exampleofgeorgiapowercredit.gif Recovering the cost of these credits is accomplished through block purchases of green energy through the power company , where environmentally driven consumers or corporations wishing to present to the public their environmental consiousness purchase thousands even millions of these green watts of electricity.
and yes most states offer several incentives to consumers to purchase solar pannels and wind turbines and a large variety of green products.
in fact the federal government has a tax credit for home owners that will pay for 30% of the entire installation cost.
below is a link to info on tax credits
http://www.energystar.gov/index.cfm?c=tax_credits.tx_index 
