There are so many ways to store alternative energy that I can not and will list them here. The fact that the carbon industry claims there is no way to do it shows you how afraid they are of these plans being implemented.
German Plant to Produce Methane Using Surplus Green Energy
Published on January 28th, 2013 by Yale Environment 360
The plant, which will use technology developed by Stuttgart-based SolarFuel, reportedly will produce enough methane to run 1,500 of the new natural-gas vehicles Audi is planning to start selling this year.
To produce the methane, the company will utilize a combination of technologies: electrolysis, in which water is split into its hydrogen and oxygen components, and methanation, in which the hydrogen is combined with carbon from carbon dioxide to produce methane.
Go there and read. More next time.