Solar panals on old roof
I live on Long Island and have been offered free solar panals thru our electric company. Someone came out and inspected the roof, we were accepted for the solar panals, I signed to get the building permits. But now I'm having second thoughts, the roof is 17 yrs old, I don't plan on replacing for at leat 5 yrs. is there any down side to the solar panals....is there something I'm not seeing, I've noticed many of my neighbors were offered same thing and aren't going forward with it...please advise me....thanks in advance for your help. FYI was told 82% of electricity will be from panals???I will have a60% reduction in electric bills.