Question 1

How long does NEM 2.0 grandfathering last in California?

Accepted Answer

NEM 2.0 grandfathering lasts 20 years from a system’s Permission to Operate (PTO) date, per CPUC Decision D.22-12-056. This calculator adds 20 years to your PTO date to estimate the expiration.

Question 2

What PTO date qualifies for NEM 2.0?

Accepted Answer

A PTO date on or before April 15, 2026 locks in NEM 2.0. After that date, systems are on NEM 3.0 (Net Billing Tariff). The NEM 2.0 enrollment window is now closed.

Question 3

Does adding a battery end my NEM 2.0 grandfathering?

Accepted Answer

Generally no — a battery is a load-side addition and does not require a new solar interconnection application, so it does not reset the 20-year clock, as long as you stay within the 10% / 1 kW solar expansion limit. See our adding-a-battery guide for details.

NEM 2.0 Expiration Calculator

NEM 2.0 Grandfathering Calculator

Want to protect or extend your NEM 2.0 system?