California’s rooftop solar credits ruling, explained for homeowners

The case in one timeline

Dates from the courts’ published opinions and the CPUC’s net billing page, checked September 2026.

The challengers were the Center for Biological Diversity, the Environmental Working Group and the Protect Our Communities Foundation. The CPUC was the respondent, with PG&E, Southern California Edison and SDG&E as real parties in interest.

What the Supreme Court decided, and what it didn’t

The Supreme Court’s case was about how much courts should defer to the CPUC. For decades, courts upheld the Commission’s reading of the Public Utilities Code unless it failed “to bear a reasonable relation to statutory purposes and language,” a test from a 1968 case called Greyhound. The court held that this “highly deferential approach” no longer applies after the Legislature expanded judicial review of most Commission decisions. California Supreme Court·checked Sep 23, 2026

It was careful about the limits: “We do not decide whether the court’s ultimate conclusion that the tariff is consistent with section 2827.1 is correct or incorrect — only that the Court of Appeal erred by applying an unduly deferential standard of review to reach that conclusion.” Justice Kruger wrote the opinion; Chief Justice Guerrero and Justices Corrigan, Liu, Groban, Jenkins and Evans concurred.

That is why headlines in August 2025 read as a win for rooftop solar while the tariff itself stayed in place: the court changed how the rule would be reviewed, not the rule.

What the Court of Appeal decided in March 2026

Back in the Court of Appeal, the question was whether the tariff fit Public Utilities Code section 2827.1, the 2013 law that told the CPUC to replace the original net metering program. The court noted the Legislature had directed that the successor tariff be “based on the electrical system costs and benefits received by nonparticipating customers” and that it “prevents a cost shift to non-NEM customers.” Court of Appeal·checked Sep 23, 2026

Applying the stricter review, it concluded the Commission “did not fail to proceed in the manner required” by the statute “and did not otherwise err or abuse its discretion when it adopted the successor tariff,” and affirmed. It also said nothing in the statute precludes the Commission “from revising the tariff in the future upon new or additional evidence” about its benefits and costs.

What the ruling means for your solar credits

• On NEM 1.0 or 2.0 already: nothing changes from this case. The CPUC says NEM 2.0 customers may stay on it for 20 years from the date they interconnected, or switch to the current tariff. CPUC·checked Sep 23, 2026
• On net billing now: your plan continues. The CPUC describes a nine-year legacy period guaranteeing net billing for the original interconnecting customer.
• Buying solar now: you will be on net billing, where exports are credited at values based on the CPUC’s Avoided Cost Calculator, “usually lower than the retail rate.” That makes using your own solar power, often with a battery, worth more than exporting it.

For the numbers behind those choices, see NEM 2.0 vs NEM 3.0 in California, whether solar still pays under net billing and battery payback under NEM 3.0.

Rules that often get mixed up with this ruling

• The income-graduated fixed charge on utility bills is a separate CPUC proceeding; see the new fixed charge on California bills, explained.
• Solar lease transfers when you sell depend on the terms of your lease or PPA; see what AB 942 proposed, and why it is not law.
• Lawsuits against solar companies are about contracts and sales practices, not export credits; see solar lawsuits in California.

What rooftop owners should do now

1. Check your interconnection date and billing plan on your utility bill or account.
2. If you are on NEM 2.0, note the 20-year end date so a future system change doesn’t surprise you.
3. Before adding panels or replacing equipment, ask your utility in writing whether the change affects your plan.
4. If you are shopping, compare quotes on self-consumption and battery sizing, not on export credits alone.

Roof work under an existing system can also raise plan questions; see removing and reinstalling panels and whether your roof is ready for solar.