The availability of solar power at night or on cloudy days just improved 0% in 16 months. Saying that solar is okay because it's hooked up to the grid is not an answer, because that's just another instance of a reliable energy source (fossil fuels, nuclear, hydro) bailing out an unreliable one (solar, wind).
1) You're still using MUCH less overall fossil fuels. A 40% reduction in fossil fuel use would do wonders for the world economy and be a huge step forward in reducing emissions. 2) If other people are feeding power back into the grid, then you can be using their solar power. It's sunny somewhere, right?