Why the value of a solar system's export depends entirely on which compensation structure the local utility actually uses — and why that answer, not the panels themselves, determines whether a battery pays for itself.
Two solar systems can be identical — same panels, same inverter, same roof, same annual production — and still have meaningfully different economics, for a reason that has nothing to do with the equipment. It comes down to how the utility compensates energy the system exports to the grid. Under one structure, exported energy is worth about the same as the energy the customer would otherwise buy. Under the other, it's worth noticeably less. That single difference changes not just the payback math, but what a well-designed system should even look like.