But Jaffe believes there is one area in the next decade where energy storage will be the killer app, and that is as a grid-scale dance partner to optimize gas-fired generation.
The concept is you have a large combined cycle natural gas plant and a large battery next to it and you use batteries as buffer between grid demand and power plant capability (this is similar to the model that gigafactory storage company Alevo is proposing). The concept is to use the batteries to meet fluctuating demand and buffer the combined cycle gas plant. That lets the generator run more efficiently at optimal heat rates most of the time, not ramping up or down.
If you are overproducing, you shunt electricity to the battery and if under-producing, you discharge from the battery…You can turn a single combined cycle plant into something that has the same power or capability as ten peaker plants. You can produce base-load power at a base-load rate, but you have the ability to dispatch and take on what peakers do. I see this as the most exciting application for batteries.
Jaffe’s company has modeled this interaction, looking at a 1,200 MW gas plant in tandem with a 1,600 MWh battery and the results have been strongly positive. The modeling assumes a 15% premium for the more valuable energy on demand, but the real value comes from the fact that the gas plant is always operating at peak efficiency. Jaffe uses the analogy of traveling by Prius versus using an 18-wheeler for the same trip: it’s just so much more efficient that one saves huge amounts on the fuel.
