Batteries and solar have been beating lifetime cost of fast response gas turbines for five years or more. Now with uncontrolled fossil fuel cost spikes the operating costs of gas are highly variable compared to the pretty much flat investment and operating cost on battery + solar. if one were comparing battery plus renewables for full seasonal offsets are tighter, but the costs are so much lower, you can provision more and plan to dump power in the summer (or maybe not as this last long hot fossil fueled climate change summer will drive new demand for a/c)