Electricity is the perfect form of power in all respects but one. It can be produced and used in many different ways, and it can be transmitted easily, efficiently, and economically, even over long distances. However, it can be stored directly only at extremely high cost. With some clever engineering, however, we should be able to integrate energy storage with all the important modes of generation, particularly wind-generated power.

Right now, to store electricity affordably at grid-scale levels, you need to first convert it into some non-electrical form: kinetic energy (the basis forflywheels), gravitational potential (which underlies all pumped-hydro storage), chemical energy (the mechanism behind batteries), the potential energy of elastically strained material or compressed gas (as in compressed air energy storage), or pure heat. In each case, however, you lose a significant percentage of energy in converting it for storage and then recovering it later on.

What if instead you were to completely integrate the energy storage with the generation? Then you wouldn’t have to pay for the extra power-conversion equipment to put the electricity into storage and recover it, and you wouldn’t suffer the losses associated with this two-way conversion. One of the most attractive ideas, I believe, is to integrate storage with wind-generated power. I’ll come back to that in a minute.  cont'd