Here is a magnificent piece on energy storage: a perfect blend of the basic science and economics. It’s a very readable explanation of how and why storage will be required to integrate significant amounts of renewables on the grid.
Today, the vast majority of energy storage is accomplished with pumped hydro. The problems with this, however, are a) only certain (hilly) terrains are appropriate to implement this inexpensively, and b) the stored energy is not portable, i.e., it cannot be used in transportation, which accounts for 40% of our total energy needs.
This gives rise to chemical solutions, also discussed in the piece. Personally, I’m betting on Windfuels, a 2GreenEnergy client, which sports a remarkable breakthrough in synthetic fuels.
“the stored energy is not portable, i.e., it cannot be used in transportation”
It can be if the vehicles are electrically powered, e.g. BEV’s, which is currently the most efficient method by a long way.
Battery technology is progressing all the time and will probably make BEV’s viable in the not too distant future.
Windfuels, IIRC, needs to have concentrated CO2 from a coal or NG plant along with a constant supply of electricity to produce their fuel.
The end result of an approach like this would be to extend the amount of time we burn fossil fuels. We’d get dependent on the supply and procrastinate closing down the burner.
We need solutions that get us off fossil fuels, not ones that prolong the life of fossil fuels.
Concrete plants are another potential source.