Germany has the world’s largest photovoltaic market. They did this with an innovative program that encourages homeowners to install solar. Rather than take the net metering approach (common in the US) in which excess energy is sent into the grid with the homeowner generally getting paid for it,they instead install the solar outside the meter and send all the energy into the grid. The homeowner pays the regular bill BUT is compensated at three times the going rate for energy generated. While a rate like that would probably have to be subsidized here in the US (and lots of energy already is subsidized), the program has had spectacular results.
The tariffs have been around since 2000 in Germany and, in that time, the proportion of energy derived from renewable sources has doubled. Germany actually reached their goal of 12.5% green energy three years early and increased its target to 27% green energy production by 2020.