California is the largest solar market in the U.S. by a large margin — but 2026 is a different financial picture than 2023. The federal Section 25D homeowner solar tax credit expired December 31, 2025, and NEM 3.0's export rate cuts have reshaped the payback math. California solar still makes sense, but you need current numbers, not the legacy estimates that still populate most installer websites.
Disclaimer: All cost and savings estimates are based on NREL PVWatts data, Lawrence Berkeley National Laboratory installer pricing surveys, and California CPUC NEM 3.0 tariff filings. The federal Section 25D solar tax credit expired December 31, 2025 — it is not included in any calculation on this page. Get at least three installer quotes. Actual results vary by roof orientation, shading, utility, and electricity rate.
Key Takeaways
- A typical 9 kW California system costs $25,000–$33,750 in 2026 — no federal credit applies
- Under NEM 3.0, a battery is essential for strong ROI — export rates dropped ~75% from NEM 2.0 levels to ~$0.04–$0.08/kWh
- California electricity rates average $0.30+ /kWh in PG&E territory — high rates accelerate solar payback
- Typical 25-year savings: $35,000–$50,000 for solar + battery combined; payback 9–13 years depending on utility
What Our Calculator Shows for California (9 kW System)
The table below shows pre-computed results for a typical California solar installation in 2026. We use a 9 kW system because it's the national median size for new residential installations according to Lawrence Berkeley National Laboratory's Tracking the Sun dataset.
| Parameter | PG&E Territory | SCE Territory | SDG&E Territory |
|---|---|---|---|
| System size | 9 kW | 9 kW | 9 kW |
| Peak sun hours (NREL) | 5.3 hrs/day | 5.6 hrs/day | 5.8 hrs/day |
| Annual production (est.) | 14,200 kWh | 15,000 kWh | 15,550 kWh |
| Installed cost (2026) | $25,000–$33,750 | $25,000–$33,750 | $27,000–$35,000 |
| Federal credit (Section 25D) | Expired — $0 | Expired — $0 | Expired — $0 |
| State solar incentive | None (SGIP is battery-only) | None | None |
| Net cost after incentives | $25,000–$33,750 | $25,000–$33,750 | $27,000–$35,000 |
| Monthly bill offset (NEM 3.0) | $180–$250/mo | $190–$260/mo | $200–$280/mo |
| Estimated payback period | 9–13 years | 9–12 years | 8–11 years |
| 25-year total savings | $35,000–$45,000 | $37,000–$47,000 | $40,000–$52,000 |
Assumptions: $300/month electricity bill; south-facing roof at 20° tilt; NEM 3.0 export rates apply; 0.5%/year panel degradation; 3% annual electricity rate escalation. Run the Solar ROI Calculator with your specific bill, roof, and utility for personalized results.
NEM 3.0: The Most Important Number for California Solar in 2026
If you're evaluating California solar in 2026 and your installer's proposal doesn't explicitly address NEM 3.0, ask them to redo the analysis. NEM 3.0 fundamentally changed what surplus solar is worth.
Under NEM 2.0 (grandfathered customers): Excess solar exported to the grid earns a credit equal to the retail rate — roughly $0.30–$0.45/kWh depending on utility and time of day.
Under NEM 3.0 (all new installations since April 2023): Excess solar earns the "Avoided Cost Calculator" export rate, which reflects the utility's marginal cost to procure power. This rate averages $0.04–$0.08/kWh on most hours — roughly 85% lower than under NEM 2.0.
According to the California Public Utilities Commission's NEM 3.0 decision documentation, the avoided cost rate does increase during peak hours, sometimes reaching $0.30+ during extreme demand events. But the average across all hours is far below retail.
The practical impact: A NEM 2.0 customer with a 9 kW system might export 6,000 kWh/year and receive $1,800 in export credits (at $0.30/kWh). The same NEM 3.0 customer exporting 6,000 kWh receives roughly $360 in credits (at $0.06/kWh average). That's a $1,440/year difference — meaningful in any payback calculation.
This is why California solar installers increasingly bundle battery storage with new systems. The battery captures midday surplus at near-zero cost and discharges during peak hours at $0.40+/kWh avoided cost — far more valuable than exporting at NEM 3.0 rates.
California State Solar Incentives in 2026
California's primary solar incentive programs for homeowners are straightforward to summarize: there aren't many on the solar-panel side. California redirected most state solar incentive money into battery storage through SGIP.
| Incentive | Applies to Solar? | Amount | Notes |
|---|---|---|---|
| Federal Section 25D | No — expired Dec 31, 2025 | $0 | Do not include in calculations; most competitor sites still show this incorrectly |
| California property tax exemption | Yes | Ongoing | Solar installations are exempt from property tax reassessment — significant in high-value CA markets |
| SGIP (Self-Generation Incentive Program) | Battery only | $200–$1,000/kWh | Available for battery storage co-installed with solar; apply through installer |
| Sales tax exemption | Partial | Varies | Some California jurisdictions exempt solar equipment from sales tax; confirm with installer |
| 30% ITC (battery only, solar-paired) | Battery add-on | 30% of battery cost | Section 48 ITC for battery storage installed with solar; reduces battery net cost by ~$4,200–$5,400 |
The property tax exemption is often overlooked but is real value in California's high-home-value markets. A 9 kW solar system that adds $15,000 to assessed value would add roughly $165/year in property taxes in a typical California county at a 1.1% effective rate — the exemption saves that amount every year for the life of the system.
How California's Electricity Rates Affect Solar ROI
One of solar's underappreciated advantages is that rising electricity rates improve solar ROI retroactively. Every rate increase makes your already-installed solar panels more valuable.
According to EIA's Electric Power Monthly, California residential electricity rates have increased steadily, with PG&E rates rising approximately 20% between 2022 and 2025. The current PG&E residential rate averages around $0.32/kWh on most plans, with peak TOU rates reaching $0.44–$0.48/kWh.
At $0.32/kWh, every 1,000 kWh/year your solar system produces and self-consumes is worth $320 in avoided grid purchases. A 9 kW system producing 14,200 kWh/year, with 60% self-consumed and 40% exported at NEM 3.0 rates, generates roughly:
- Self-consumed: 8,520 kWh × $0.32 = $2,726/year
- Exported (NEM 3.0): 5,680 kWh × $0.06 = $341/year
- Total annual value: ~$3,067/year
On a $29,000 net system cost (midpoint of the range), that's a 9.4-year payback — before accounting for battery storage, rate escalation, or the property tax exemption.
Solar + Battery vs. Solar Only in California
The decision of whether to add battery storage depends primarily on whether you're on NEM 3.0 (new installations) or NEM 2.0 (grandfathered pre-2023 installations).
NEM 2.0 customers: Battery is beneficial but not critical. Your export compensation is still at the retail rate, so the grid is functioning as your "free storage." Battery adds TOU arbitrage and resilience value. Typical battery-only payback in this scenario: 10–15 years.
NEM 3.0 customers (all new installations): Battery transforms the solar ROI calculation. Without a battery, you're exporting surplus at ~$0.06/kWh. With a battery, you're consuming that surplus during peak hours at $0.40+/kWh avoided cost — a 6–7× improvement in value per kWh. Adding a Powerwall 3 (net cost ~$9,800–$12,600 after ITC + SGIP) alongside your solar system adds roughly $900–$1,200/year in additional value. Battery payback within the combined system: 8–12 years.
Use the Battery Storage Calculator to model the California NEM 3.0 combined scenario with your specific utility and rate.
What to Do Next
Confirm your utility and current rate plan.
PG&E, SCE, and SDG&E have different rate schedules, TOU structures, and NEM 3.0 export rates. Your utility territory determines which numbers apply to your specific calculation.
Run your personalized solar ROI estimate.
Use the Solar ROI Calculator with your actual monthly bill, roof size, and orientation. The pre-computed table above uses typical inputs — your specific numbers may differ meaningfully.
Check SGIP availability before signing any solar contract.
SGIP battery rebates can reduce battery net cost by $2,700–$13,500 depending on your eligibility tier. Verify program availability at selfgenca.com and confirm your installer is SGIP-approved.
Get 3+ quotes from California-licensed installers.
California requires CSLB licensing for solar contractors. Quotes for the same 9 kW system often vary by $4,000–$8,000. Compare carefully and verify SGIP paperwork is included.
Get your California solar estimate in 60 seconds
Enter your utility, monthly bill, and roof size — see your 2026 payback period and 25-year savings with no email required.
Adding battery storage? Our Battery Storage Calculator models California SGIP rebates, NEM 3.0 self-consumption value, and PG&E/SCE/SDG&E TOU rate optimization.
Related Guides
- California Solar Incentives 2026 — Everything available for California solar after Section 25D expired: SGIP, property tax exemption, and NEM 3.0 explained.
- California SGIP Rebate Guide 2026 — Deep dive into SGIP tiers, eligibility, application process, and current program funding status.
- Home Battery Storage ROI: California 2026 — Battery-specific ROI analysis for California homeowners under NEM 3.0.
- Is Solar Worth It in 2026? — National state-by-state solar ROI guide with Section 25D expiration context.
