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Net Metering 3.0 Explained: Why California Solar Now Requires a Battery

How California NEM 3.0 (Solar Billing Plan) cut solar export credits by 75%, and why adding a battery storage system restores solar investment ROI.

By the WattWise Editorial Team 8 min read

On April 15, 2023, the California Public Utilities Commission (CPUC) enacted the Net Billing Tariff — colloquially known as NEM 3.0. The regulatory change fundamentally disrupted residential solar economics in the nation’s largest clean energy market.

Understanding NEM 3.0 rules is essential for California homeowners evaluating solar quotes today.

What NEM 3.0 Changed

Under the prior Net Metering 2.0 rules:

  • Homeowners exported excess daytime solar electricity to the utility grid in exchange for full retail credits (often $0.30 to $0.40 per kWh).
  • At night, they drew power back from the grid, offsetting daytime credits one-for-one.
  • Solar-only arrays achieved rapid payback periods of 5 to 6 years.

Under NEM 3.0:

  • The CPUC adopted an “Avoided Cost Calculator” model.
  • Daytime solar export compensation was slashed by approximately 75%, from ~$0.30/kWh down to an average of $0.05 to $0.08 per kWh.
  • Exporting solar electricity to the grid during the afternoon is now mathematically irrational.

The Solution: Pair Solar With Battery Storage

Under NEM 3.0, the economic goal is 100% self-consumption:

  1. Your solar panels power your home during the day.
  2. Excess daytime solar generation charges a home battery (such as Tesla Powerwall 3, Enphase 5P, or FranklinWH) instead of exporting to the utility grid for pennies.
  3. During expensive peak evening hours (4:00 PM to 9:00 PM when utility rates reach $0.55+/kWh), the battery discharges to power your home.
  4. By avoiding $0.55/kWh utility rates, the solar-plus-storage system achieves a strong 7 to 9-year payback period while providing blackout protection.

Sources

Frequently asked questions

What did NEM 3.0 change in California?
NEM 3.0 cut the credit utilities pay homeowners for exporting excess solar power to the grid by roughly 75%, shifting from retail net metering to avoided cost wholesale rates.
Is solar still worth it in California under NEM 3.0?
Yes, but only when paired with a home battery storage system that stores daytime solar energy for use during expensive evening peak hours.

About the author

Written by the WattWise Editorial Team, which researches and maintains every guide on this site. Read more about our editorial standards or contact us with corrections.

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