Demand side management is a nice concept, but it is neither free nor a cure-all:

It has real costs because it limits the utilization of involved infrastructure and is simply not feasible for a lot of industries. It does not help when residential demand exceeds the available supply either.

The most practical solution will probably be a mix of overprovisioning (especially considering how cheap solar panels have become), battery storage and fuel powered fallback, with the balance shifting as long as batteries and panels get cheaper.

Grid level battery storage is already coming online at scale (e.g. https://www.ess-news.com/2025/08/18/statera-energy-powers-up...).

LiFePo cells are already down to ~$60 for 1kWh (8000 cycles), which is pretty palatable for a lot of applications and prices still trend down.