Comment by AnthonyMouse

> The battery cost me about 200€/kWh and is expected to last a few thousand cycles. That works out to a couple of cents per kWh. That’s not terribly expensive and grid scale storage has economies of scale that my balcony setup can’t match.

The up-front cost of just the battery itself isn't the total cost. You have to add installation, land, time value of money (interest) since you're paying up front for something and then only getting those charge cycles over several years, etc.

Ends up being 10-20c/kWh, and that's on top of what you pay for the electricity to put into it.

Also gets worse the more capacity you want to have, because then you're doing less than a full charge cycle more of the time, which means it takes you longer to do those few thousand cycles, which means you pay more in interest.