NEM 3.0, explained in plain English
California's Net Billing Tariff changed what your solar is worth — and why a battery is now the heart of the economics. Here's the no-jargon version.
If you have solar in California — or you're thinking about it — NEM 3.0 is the single biggest factor in what your panels are actually worth. It changed the math completely, and most of the old "your meter runs backwards" advice no longer applies.
What NEM 3.0 actually is
NEM 3.0 — officially the Net Billing Tariff (NBT) — is California's solar compensation rule that took effect in April 2023 for PG&E, SCE, and SDG&E. It governs how much you're paid when your solar sends power back to the grid.
Under the old NEM 2.0, exported energy earned roughly the full retail rate — often $0.30–$0.40 per kWh. Send a kWh to the grid at noon, get a credit worth a kWh at dinner. Very generous.
The big change: export is now paid at "avoided cost"
NEM 3.0 replaces retail-rate export credits with the Avoided Cost Calculator (ACC) — a schedule of 576 different export rates (one for every combination of month, hour, and weekday/weekend). The practical result: midday export is worth far less — on the order of $0.05–$0.08 per kWh on average. The high-value windows are summer evenings (roughly 4–9 PM), when export can reach $0.10–$0.30+/kWh — but that's exactly when your panels are winding down.
Why this makes a battery so valuable
Here's the key insight. A kWh you export at midday might be worth 6 cents, but a kWh you use from your own panels instead of buying from the grid in the evening is worth your full retail rate — often 40–60 cents on a time-of-use plan. A Powerwall lets you store cheap midday solar and use it during expensive evening peak instead of selling it back for pennies. That's why NEM 3.0 turned home batteries into the centerpiece of a good solar case.
Your export rate is locked to your "vintage"
When your system receives Permission to Operate (PTO), your ACC export values are locked in for 9 years based on your PTO year. Any honest savings estimate has to use your year's values, not a generic average.
What this means for you
- Solar alone still saves money, but payback stretched to ~12–15+ years under NEM 3.0.
- Solar + a battery is where the economics work now — typically 6–9 year payback in California.
- Your rate plan matters as much as your hardware — the value of shifting energy depends entirely on your time-of-use windows and ACC vintage.
Doing this well by hand is tedious. That's the problem SolDial was built to solve — it loads your real plan, models NEM 3.0 with your vintage, and automates the battery and EV charging around it.
General information, not financial advice. Your results depend on your utility, rate plan, usage, and system.