The BIGGEST problem with clean energy

I really wonder why in such videos there are always some essencial topics are missing. 
You can store some of the renewable energies before transforming them to electricity. Most obvious: Stop using bio gas in gas turbines when there is enough energy in the grid. Bio gas can be stored in huges amounts. The solar power plant at 1:27 produces heat in the first palce. This heat can be stored for a long time without losses. So you can chose when to use the heat to generate electricity.
But at least as efficient than storing the enegy is when you adapt the time when you use engergy. If you have a well isolated house you can cool it down or heat when there is enough engery and switch off the heat/AC when there is a lag of energy. Same might be possible for the parts of industry that needs alot of energy. Maybe we stop blast furnace when we know that we'll have energy shortage for a longer period (e.g. mid Winter).