We already have enough battery manufacturing capacity to build hours worth of grid storage over the next 5 years and more is coming online at double digit growth rates. What’s missing is the demand for grid batteries which is still relatively low.

Right now California only wastes ~5% of its solar output per year but most days don’t have a surplus. That’s not enough capacity for nighttime storage to be worth it, you need consistent daily oversupply before charging becomes “free”.

However, because of the demand curve batteries are viable for peaking power. Which is why some farms are built with “4h” aka 50% of daily output worth of battery storage. Thus we are past the initial tipping point of occasional viability where sometimes it’s a good idea. The big one is at roughly 5c/kWh where natural gas is no longer economically viable and the grid isn’t dependent on fossil fuels.

5c/kWh * 3,000 full discharge cycles ~= 150$/kWh total instillation cost including labor etc. Increase or decrease based on specific battery technology and it’s lifespan.