We have a kilowatt solar grid tie setup. It knocks 50 bucks off the power bill in 9 months of the year. At times the power meter stops, sometimes rolls backwards. Its a hobby and started at 100 watts.
I was going to sell my setup a few years ago til I found how much my mother loved the fact it lowered the power bill. I kept it and added 300 watts in polycrystal panels and 2 mo 250 watt gtis.
Our power company charges a service fee and a per kw fee. If we used no power, we would still have a fee.