[bboygravity]

Not if you consider that you need to either renew or add battery capacity (and panels and power electronics) after x years? Or did you take that into account?

[onlyrealcuzzo]

That doesn't impact payback cost, if the batteries & panels last longer than 8-9 years (and they do).

It's just one metric.

[triceratops]

x = ~25 years for the panels. They're paid off long before that.