1878: Augustin Mouchot displayed a solar power generator at the Universal Exhibition in Paris
1941: The World's first Megawatt wind turbine [ Smith / Putnam ]
The rationale for renewable energy subsidies, mandates, and feed-in tariffs (FITs), has been that the technology is young and needs a leg up. Renewable energy technologies are not young. They are older than nuclear power.
California has been trying to do renewables since 1978 : for 38 years. In 2014, natural gas still made 61.3% of California's electricity.
The two main problems facing renewable power are very low power densities, and intermittent output. Such low power densities means vast amounts of renewable energy plant must be built. It would still not be very non-carbon. We'd still need about as much fossil fuel plant as before because solar delivers nothing when British peak electricity demand calls - at about 5pm in deep mid-winter. The minimum output of British wind - over the entire country - is less than 1% of nameplate capacity.
Calls for more renewable energy should be recognised as either stupid, or malicious. Many of the people advocating renewable energy have a Luddite and/or neo-Malthusian worldview. It doesn't matter to such people whether we decarbonize energy. What really counts for them is that we slow, or hobble, industrial society by making energy expensive. They'll never admit this, because it's a certain vote loser. Hence the lies :- our renewable powered world is just a few years away ...