I think it is not only about economics. Producing my own electricity in the past made me very proud on top of doing something for the environment..
Running a so called stand alone system (not connected to the grid) in the late 90th made me learn not to waste energy any more. 12 years later I installed a 20 kWp PV which gives more than 1000 Euro/month return from EAC for 15 years. ROI is already happening.
Max