Key Takeaways
- • March 2026 appellate court upheld NEM 3.0 — no reversal coming.
- • Export credit is now $0.05–$0.08/kWh, down 75% from NEM 2.0.
- • Battery pairing is mandatory math — a single battery roughly doubles annual savings.
- • Payback compresses from 9–13 years (no battery) to 5–7 years (with battery).
- • Replace the roof FIRST — mounts over old shingles void warranty and create leak paths.
In This Guide
What NEM 3.0 Actually Changed
Under NEM 2.0 (April 2017 through April 2023), surplus solar you exported to the grid earned credits at approximately the retail rate, averaging roughly $0.30 per kWh across California's three investor-owned utilities. Payback for a typical residential system ran 5 to 6 years, and battery storage was optional.
NEM 3.0, effective for new interconnections on and after April 15, 2023, switched export compensation to the Avoided Cost Calculator (ACC)rate. ACC varies by hour and season, reflecting what the utility would otherwise pay wholesale for equivalent electricity. In practice, 2026 export rates average $0.05 to $0.08 per kWh — a roughly 75 percent cut. At the same time, retail rates have climbed: PG&E averages $0.44, SCE $0.38, SDG&E $0.51 per kWh in 2026.
The net effect: exporting energy to the grid is now 5 to 8 times less valuable than consuming it yourself. This single economic reality drives every other NEM 3.0 design decision — battery sizing, time-of-use optimization, load shifting, EV charging schedules, and roof-replacement timing.
Customers already on NEM 2.0 retain that tariff for 20 years from interconnection date (grandfathered). Only new installations enroll in NEM 3.0. The March 2026 appellate court ruling confirmed this framework is durable, ending speculation that regulatory pressure would restore NEM 2.0-like rates.
Why Battery Pairing Is Now Mandatory Math
A 7 kW solar system in PG&E territory generates about 10,000 kWh per year. The critical question is what fraction of that generation you self-consume(offsetting $0.44 retail) versus export (earning $0.07).
| Battery Configuration | Self-Consumed % | Annual Value (PG&E) |
|---|---|---|
| No battery | ~35% | ~$2,000 |
| Single 13.5 kWh battery | ~68% | ~$3,500 |
| Dual 27 kWh battery | ~85% | ~$4,100 |
A single battery roughly doubles your annual savings versus no battery. A second battery adds meaningfully less (diminishing returns as you saturate daytime load-shift opportunities). Three or more batteries rarely pay back under 2026 rates unless you specifically need extended PSPS backup power or large EV charging off-peak.
A single 13.5 kWh battery adds roughly $12,000 to installed cost (before the 30 percent federal ITC brings net to ~$8,400). That incremental $8,400 typically pays back in 5 to 6 years through improved self-consumption economics, which is why nearly every 2026 NEM 3.0 residential install includes at least one battery.
Replace the Roof First
Solar panels are warranted 25 years and last 30-35 years physically. If your roof has less than 10-15 years of useful life remaining at install, it will need replacement before the solar retires. That triggers panel removal and reinstallation, typically $3,000-$5,000 plus reroofing cost. Three tactical reasons to replace the roof first:
- • Warranty integrity. Most roofing manufacturer warranties void if shingles are penetrated by solar mounts installed by someone else. Coordinating roof and solar under a single integrated scope preserves warranty.
- • Avoid the future removal bill. Removing and reinstalling panels at year 15 of a 25-year solar warranty costs $3,000-$5,000. Replacing roof before install avoids this.
- • Clean mount points. New decking and underlayment give the installer the best possible attachment surface. Retrofit mounts on 15-year-old shingles leak more often.
RoofVista matches solar-ready roof replacement projects with contractors who coordinate directly with your solar installer on mount layout, penetration flashing, and Title 24 compliance documentation.
Price a Solar-Ready Roof in 30 Seconds
Replace your roof first — then add solar. Get an instant quote from pre-vetted California contractors who coordinate with solar installers.
Interactive NEM 3.0 ROI Calculator
Size a system, utility, usage, and battery configuration to see 2026 payback math including roof-replacement coordination.
Annual Bill Savings
$3,377
Self-consumed: 7,140 kWh · Exported: 3,360 kWh
Total Out of Pocket
$40,120
System (after 30% ITC): $22,120 · Roof: $18,000
Simple Payback
11.9 yrs
Battery pairing is the dominant NEM 3.0 strategy.
Illustrative calculation using 2026 California rate assumptions: PG&E retail ~$0.44, SCE ~$0.38, SDG&E ~$0.51 per kWh; NEM 3.0 export credits ~$0.06-0.08 per kWh. Actual savings depend on time-of-use schedule, home load profile, battery dispatch behavior, and site shading. Not a binding estimate.
PG&E vs SCE vs SDG&E Under NEM 3.0
The three California investor-owned utilities apply the same NEM 3.0 export formula but have meaningfully different retail rates, time-of-use schedules, and interconnection timelines. In rough 2026 terms:
PG&E
Retail ~$0.44/kWh · Export ~$0.07/kWh · Generation ~1,500 kWh/kW/yr · Widest TOU spread enables best battery arbitrage. Interconnection 60-120 days.
SCE (Southern California Edison)
Retail ~$0.38/kWh · Export ~$0.06/kWh · Generation ~1,650 kWh/kW/yr · Highest generation volume per installed kW. Interconnection 30-45 days.
SDG&E
Retail ~$0.51/kWh · Export ~$0.08/kWh · Generation ~1,700 kWh/kW/yr · Highest retail rate makes self-consumption most valuable. Interconnection 45-75 days.
Stacking With Federal ITC, AB 888, and Title 24
- • Federal ITC (30%). Applies to solar, battery, and integrated equipment. Does not apply to roof replacement itself unless the roof work is specifically scoped for solar integration (localized reinforcement, ballasted mounts).
- • AB 888 Safe Homes Act. Up to $40K for fire-hardened roofs in High/Very High FHSZ areas. Solar-ready roof scope fits cleanly inside AB 888-qualifying work. See our AB 888 guide.
- • Title 24 cool-roof rebates. Utility IOU programs pay $0.10-$0.30/sqft for high-SRI roofs that exceed prescriptive minimum. Cool-rated shingles pair well with solar arrays because the shaded area under panels stays cooler regardless, and the exposed cool surface still earns the rebate.
- • SGIP (Self-Generation Incentive Program). Residential battery rebates of $150-$200 per kWh for equity-tier customers (CARE/FERA) and $85-$150 per kWh for standard residential. Administered through PG&E, SCE, and SoCalGas.
Vetting Solar Installers Under NEM 3.0
The California solar industry contracted sharply after NEM 3.0 took effect, with residential install volume dropping more than 60 percent year-over-year in 2023 and stabilizing at roughly half of 2022 peak through 2025. That shakeout has been uneven: high-quality installers with battery expertise are busy and booked; marginal installers who survived on NEM 2.0 quick-sell economics have closed or pivoted.
When vetting, look for: (1) CSLB C-46 solar license or C-10 electrical plus demonstrated solar experience, (2) NABCEP PV Installation Professional certification, (3) at least 5 years installing under NEM 3.0 specifically (not just under NEM 2.0), (4) integrated battery experience with Tesla, Enphase, Franklin, or SolarEdge offerings, and (5) willingness to coordinate timing with your roofing contractor. Avoid installers pitching lease-only offerings or power purchase agreements (PPAs) at 2026 rates — cash or financed ownership consistently produces better long-term outcomes for homeowners under NEM 3.0 economics.
Frequently Asked Questions
Frequently Asked Questions
What is NEM 3.0 and when did it take effect?
NEM 3.0 is the third generation of California Net Energy Metering, approved by the California Public Utilities Commission in December 2022 and effective for new solar interconnections beginning April 15, 2023. It applies to residential and small commercial customers of the three investor-owned utilities: PG&E, SCE, and SDG&E. The core change versus NEM 2.0 was a dramatic reduction in export credits. Under NEM 2.0, surplus solar exported to the grid earned roughly the retail rate (~$0.30 per kWh in many territories). Under NEM 3.0, exports earn the Avoided Cost Calculator rate, which varies by hour and season but averages $0.05 to $0.08 per kWh. Customers already on NEM 2.0 keep that tariff for 20 years from their interconnection date. Anyone installing solar in 2026 enrolls in NEM 3.0.
Did the March 2026 court ruling change NEM 3.0?
No. In March 2026, a California appellate court upheld the CPUC decision to cut export compensation, rejecting legal challenges from environmental and solar advocacy groups. The ruling confirms that NEM 3.0 is the durable framework for new interconnections in California for the foreseeable future, and it ended lingering hope among some homeowners who delayed solar decisions waiting for a regulatory reversal. The practical implication: plan your 2026 solar purchase around NEM 3.0 economics, not NEM 2.0. That means battery-first strategy, roof-timing coordination, and time-of-use optimization rather than waiting for a friendlier tariff.
Is rooftop solar still worth it in California under NEM 3.0?
Yes, but the economics only work well when you pair solar with battery storage and coordinate with roof replacement. Without a battery, a NEM 3.0 system typically pays back in 9 to 13 years, compared to 5 to 6 years under NEM 2.0. With a single battery (roughly 13.5 kWh) that lets you self-consume the bulk of your generation, payback compresses back to 5 to 7 years and lifetime savings over 25 years typically run $40,000 to $90,000 for an average California household. The mechanism: exported kWh earn $0.05-0.08, but self-consumed kWh offset retail rates of $0.38-0.51. Keeping energy on-site is 5 to 8 times more valuable than exporting it. This is why nearly every 2026 NEM 3.0 install includes at least one battery.
Should I replace my roof before or after installing solar?
Replace the roof first, unless your existing roof has more than 10 to 15 years of useful life remaining. Solar panels are typically warranted 25 years and physically last 30-35 years. If your roof is 15 or more years old at install, it will need replacement before the solar system is retired, which means paying a panel removal and reinstallation fee of roughly $3,000-$5,000 plus reroofing underneath. Worse, some roofing contractors will decline to work under live solar arrays due to liability, limiting your choices. Coordinating the replacement as a single project saves money, preserves your roof warranty (many manufacturers void warranties if panels are attached to a roof they did not cover), and lets your installer use the cleanest possible attachment hardware (flashed mounts, not hack-jobs on deteriorated shingles). RoofVista can match you with contractors experienced with solar-ready roof prep.
How big a battery do I need under NEM 3.0?
Battery sizing depends on three factors: daily solar generation (which depends on system size and utility territory), nighttime and evening household load (higher in summer AC months), and your time-of-use rate schedule. Rough rule of thumb for 2026: size battery kWh to approximately 70-85 percent of your average daily self-consumption opportunity. For a 7 kW system generating roughly 10,000 kWh per year against a 900 kWh-per-month household load, a single 13.5 kWh battery (Tesla Powerwall class) self-consumes about 68 percent of generation. Two batteries push that to 85 percent with diminishing returns. Going beyond two batteries rarely pays back under 2026 rates unless you have specific needs like backup power during PSPS outages or an EV charging off-peak. The ROI calculator on this page lets you test scenarios.
Do PG&E, SCE, and SDG&E handle NEM 3.0 differently?
The core export-credit formula is uniform across all three IOUs, but retail rates, time-of-use windows, and interconnection paperwork differ. SDG&E has the highest retail rates (~$0.51/kWh average in 2026), which makes self-consumption through a battery most valuable there and payback shortest. PG&E falls in the middle (~$0.44) but has the widest time-of-use spread, making battery arbitrage between peak and off-peak windows particularly effective. SCE has the lowest retail (~$0.38) but benefits from consistently sunny Southern California irradiance (roughly 1,650 kWh per kW DC annually versus 1,500 in PG&E territory), so generation volume partially offsets the lower rate. Interconnection timelines are generally fastest at SCE (30-45 days), moderate at SDG&E (45-75 days), and slowest at PG&E (60-120 days). Factor all three when planning project timing.
Can I stack solar with AB 888 or Title 24 cool-roof rebates?
Not directly for the solar array itself, but yes for the underlying roof replacement that precedes or accompanies the solar install. AB 888 Safe Homes Act grants (up to $40,000 for qualifying FHSZ properties) fund fire-hardened Class A roof scope including ember-resistant vents and gutter guards, which are physically compatible with solar-ready roof preparation. If you are in an FHSZ and replacing your roof ahead of solar, running the AB 888 application in parallel is efficient. Title 24 cool-roof rebates from PG&E, SCE, and SDG&E apply to the cool-rated roof surface if it meets prescriptive SRI minimums; cool-rated shingles and cool-coated metal stack cleanly with solar panel mounts. The 30 percent federal Investment Tax Credit applies to the solar + battery package but not to the roof replacement itself, though solar-specific roof work (localized reinforcement, solar mount integration) may be bundled into the ITC basis per IRS guidance.