The following links give sample data on what is expected from a 5 KW system installed in Colorado.
Dollar Production - How much money will a system produce?
Power Output - How much power will a system produce in its 1st year vs, its 25th year?
Payback - When will my system pay back the money I've invested in it and how much money will it create in power after 25 years? Return on Investment (ROI)
CO2 - How much CO2 will be saved a year by a system.
30% Federal Solar Tax Credit
30% Federal Solar Tax Credit Form (Draft 2009)
Calculate Payback Period (Residential)
Xcel Rebate Payback Feed in Tariff Calculator System Sizes Greater Than 10 KW for 2011
This tool uses inflation, panel degradation, system size and calculates the system output.