California solar guide
DIY solar in California: incentives, sizing, and the off-grid angle
California is the biggest DIY solar market in America and also the most complicated since NEM 3.0 took effect in April 2023. Export compensation dropped roughly 75% — which means batteries are now essential to capture value from a grid-tied system, and fully off-grid setups are increasingly competitive with grid-tie for new installs.
California still offers full property-tax exemption on PV systems and the federal 26% credit applies — but no state income tax credit and no sales tax exemption on equipment. Net-net, the install math is harder than it was pre-2023.
Incentive snapshot
As of mid-2026. Verify on your state's energy website before relying on the dollar figures.
- Federal Residential Clean Energy Credit
- 26%
- State tax credit
- —
- Sales tax exemption on solar equipment
- No
- Property tax exemption
- Yes
- Net metering
- Limited / restructured
- SREC market
- None
- Average peak sun hours
- 5.4 hrs/day
- DIY-permit friendly
- Yes
Phases down: 30% through 2025 → 26% in 2026 → 22% in 2027 → 0% under current law. Dwellings only — vehicle/RV systems don't qualify.
Equipment is taxed at standard sales tax rate.
Adding solar doesn't bump your assessed value.
NEM 3.0 (since April 2023) pays ~25% of NEM 2.0 export rates — batteries are now essential for ROI on grid-tied systems.
No SREC revenue available in this state.
Used to size your array — more sun hours = fewer panels needed for the same output.
California allows homeowner permits for own-occupancy installs. Some jurisdictions require licensed contractor sign-off on grid-tie connections.
DIY install angle in California
California specifically allows homeowner permits for own-occupancy installs in most jurisdictions. The catch: many cities require a licensed electrician to sign off on the grid-tie inverter connection, and PG&E / SCE / SDG&E all require their own interconnection paperwork before they'll authorize export.
For off-grid or behind-the-meter (no export) battery systems, the permit path is much simpler. Most counties treat off-grid as standard electrical work; no utility involvement needed.
Fire codes matter in California. CalFire and local AHJs require specific rapid-shutdown (NEC 690.12) compliance and battery setback distances from structures. The newer Tigo, Enphase, and SolarEdge optimizer/microinverter systems handle this automatically. DIY string inverter setups need careful planning.
Sizing for California sun
California averages 5.4 peak sun hours/day, with the Mojave and Imperial Valley regularly hitting 6.5+ and the foggy NorCal coast dipping to 4.5. Sizing for the average is the right approach for most builds.
For an off-grid build powering a typical 5 kWh/day load (cabin, large van, small tiny home), expect to need roughly 1.3 kW of panels and ~10 kWh of LFP battery. Hot summers in inland CA push AC load and require oversizing.
Battery chemistry in California heat: LiFePO4 (LFP) handles 110°F+ enclosed-space temperatures far better than NMC. AGM works but ages faster. Skip flooded lead-acid for inland CA — the heat will shorten cycle life dramatically.
Try the SolarControllerFinder builder
Enter your panels, battery bank, and load profile. We run the wiring math (NEC 690.7 cold- weather Voc derating, 690.8 ampacity) and recommend charge controllers that actually work together — ranked by price-to-trust, not by who paid us.
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