Fossil fuels have long held an advantage over renewables in that they provide a combined energy source and storage medium in one substance, be it gasoline, coal, oil or natural gas. The fact that you can save it, store it, then use it continuously whenever you need it is a tremendous convenience.
That gap is now being reduced with the advent of combined solar-storage systems. These new systems not only match the capability of fossil fuels, but can actually go them one better. How?