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Illustration · 120 half-cut cells
Solar panelQcells

Qcells Q.PEAK DUO-G6+/SC 345

120 half-cut cells. Power classes 340–355 W in the CEC list.

CEC listed · Feb 3, 2020UL 1703
Power class
  • Power (STC)345 WCEC nameplate
  • Efficiency≈19.9%calculated from area
  • %/°C Pmax−0.360CEC listing test
  • PTC / STC93%PTC 321 W (CEC)

Power classes

CEC PV Module List (Oct 7, 2026) · Cali-Graf calculation · 4 models
ModelPmaxVoc, VIsc, AVmp, VImp, AEfficiencyPTCCEC listed
Q.PEAK DUO-G6+/SC 340340 W40.2410.6833.4510.16≈19.7%316 WFeb 3, 2020
Q.PEAK DUO-G6+/SC 345345 W40.4910.7333.7610.22≈19.9%321 WFeb 3, 2020
Q.PEAK DUO-G6+/SC 350350 W40.7310.7934.0710.27≈20.2%326 WFeb 3, 2020
Q.PEAK DUO-G6+/SC 355355 W40.9810.8434.3810.33≈20.5%330 WFeb 3, 2020
≈ efficiency = Pmax ÷ CEC-listed area 1.73 m².
CEC note: Formerly listed under Hanwha Q CELLS

Build & dimensions

CEC PV Module List (Oct 7, 2026)

Heat & cold behaviour

CEC PV Module List (Oct 7, 2026) · Cali-Graf calculation
CEC listing test
Pmax coefficient γ−0.360 %/°C
Voc coefficient β−0.276 %/°C
Isc coefficient α+0.047 %/°C
Operating cell temperatureNOCT 45.1 °C
Vmp coefficient ≈ γ − α (CEC); used only for the hot-roof voltage estimate.

Away from lab conditions — CEC listing test points

ClassPmax at NOCTVmp × Imp at NOCTPmax at 200 W/m²Low-light efficiency vs STC
340 W243.3 W30.35 V × 8.02 A62.7 W92%
345 W247 W30.63 V × 8.06 A63.6 W92%
350 W250.5 W30.91 V × 8.1 A64.5 W92%
355 W254.3 W31.19 V × 8.15 A65.5 W92%
Pmax = Vmp × Imp from the CEC listing; low-light efficiency = Pmax at 200 W/m² ÷ (20% of STC Pmax).

Independent reliability testing

Kiwa PVEL Scorecard · RETC PV Module Index
2022
PVEL Top Performer
closely related product name
1
Tests passed as Top Performer
MSS
11
PVEL Scorecards
Qcells named Top Performer, 2016–2026
2023, 2026
RETC Overall Highest Achiever
Qcells, manufacturer level

PVEL Top Performer tests

YearProductTests
2022Q.PEAK DUO G6+ (closely related product name)MSS

Tested bill of materials

Details describe the tested sample, not every module of the series.

RETC PV Module Index — Qcells

YearRecognition
2023Overall Highest Achiever; High Achievement in Performance (Module efficiency, Pan file performance); High Achievement in Reliability (Damp heat test, Pid resistance, Thermal cycle test)
2024High Achievement in Performance
2025Performance High Achiever
2026Overall Highest Achiever; High achievement in performance; High achievement in reliability; Performance discipline high achiever (Conversion efficiency, Iam, Letid, Lid, PTC-to-STC, Temperature coefficient); Quality discipline high achiever (BOM verification); Reliability discipline high achiever (Sdml, Tc, Uvid, Budt, Damp heat, Hdt, Pid)

Inverter compatibility & string sizing

CEC PV Module List (Oct 7, 2026) · Cali-Graf calculation · NLR PVWatts v8 · inverter datasheets · NLR SAM inverter library · CEC Grid Support Inverter List (Oct 7, 2026)
43.1 V
Voc when cold
per panel
27 V
Vmp when hot
per panel
13
Max panels / string
max DC 600 V
3
Min panels / string
MPPT from 60 V
Defaults come from NLR TMY weather (coldest hour, hottest modeled cell). Code calculations (NEC 690.7) use the ASHRAE extreme annual minimum, which is usually colder — enter it above. β is the CEC-measured coefficient; NEC 690.7 calculations use the datasheet value.

String inverters most named in SoCal permits

InverterMax DC inputMPPTWindow sourcePanels per string
Tesla 1538000-xx-y600 V60–480 Vdatasheet3–13
Solis (Ginlong) S6-EH1P10K-H-US600 V80–520 Vdatasheet3–13
Solis (Ginlong) Solis-1P7.6K-4G-US600 V100–500 Vdatasheet4–13
Qcells Q.VOLT H7.6SX498 V234–498 VCEC test window9–11

Microinverters (one per panel)

MicroinverterRecommended module powerMax DC inputMPPTVoc cold / Vmp hotCheckDC/AC
Enphase IQ8PLUS-72-2-US235–440 W60 V29–45 V43.1 / 27 V⚠ Works; below MPPT at peak heat1.19
Enphase IQ8X-80-M-US320–540 W79.5 V43–60 V43.1 / 27 V✗ Not a match: module voltage below MPPT range0.91
APsystems (Alt Power System) DS3-L265–570 W60 V28–45 V43.1 / 27 V⚠ Works; below MPPT at peak heat0.44
Enphase IQ8M-72-2-US260–460 W60 V30–45 V43.1 / 27 V⚠ Works; below MPPT at peak heat1.06
Enphase IQ8A-72-2-US295–500 W60 V32–45 V43.1 / 27 V⚠ Works; below MPPT at peak heat0.99
Voltage check against the microinverter datasheets — confirm the pairing on the manufacturer’s module compatibility list. Rows appear only when the panel’s power is inside the microinverter’s recommended module power range.
SolarEdge and other optimizer-based systems size strings by the optimizer rules — use the manufacturer’s designer. Reference inverters: most named in SoCal permits since Oct 2024.

Expected production in Southern California

NLR PVWatts v8 · Cali-Graf calculation
CitykWh / kW / yrkWh / panel / yrkWh / system / yrSun, kWh/m²/day
Los Angeles1,67657811,5646.08
Palmdale1,83563312,6626.69
Chula Vista1,69658511,7026.11
Huntington Beach1,64356711,3375.89
Riverside1,69658511,7026.21
Santa Clarita1,72459511,8966.28
755Jan756Feb969Mar1,071Apr1,058May1,124Jun1,184Jul1,198Aug1,047Sep924Oct794Nov687DeckWh per month · Los Angeles
Estimate for comparison, not a quote: shading, roof orientation and local losses change real output. Roof mount, 20° tilt, south, 14% system losses.

Other versions of this panel

CEC PV Module List (Oct 7, 2026) · building permits
Qcells Q.PEAK DUO BLK-G6+/SC
Color version · 330–350 W · listed 2021 · 1 SoCal permits

Compare with similar 345 W panels

CEC PV Module List (Oct 7, 2026) · Kiwa PVEL Scorecard · JinkoSolar datasheets · building permits
PanelPmaxEfficiencyγ Pmax (CEC)Voc, VIsc, APVEL (product / brand)SoCal permits (series)
Qcells Q.PEAK DUO-G6+/SC 345345 W≈19.9%−0.36040.4910.73brand 11×—
LONGi LR4-60HPB-345M345 W≈19.5%−0.33940.211.06product 2021, 2022193
JinkoSolar JKM345M-60HBL345 W≈20.4%−0.40641.210.91brand 12× (2014–2026)45
REC Group REC345AA345 W≈20.5%−0.27943.410.12brand 9× (2016–2025)30
Same fields from the same sources for every row; ≈ efficiency is calculated from the listed area. Comparable series: other brands, same product group, power range covering this class.

About Qcells

CEC PV Module List (Oct 7, 2026) · Kiwa PVEL Scorecard · RETC PV Module Index · building permits

Other series by SoCal permits

Q.PEAK DUO BLK ML-G10+ · 221Q.PEAK DUO BLK ML-G10.C+ · 124Q.TRON BLK M-G2+ · 40Q.TRON BLK M-G2.H+ · 33Q.TRON BLK M-G2.C+ · 24Q.TRON M-G2+ · 20

Questions & answers

How efficient is the Qcells Q.PEAK DUO-G6+/SC 345?

Calculated from the panel area (1.73 m²): about 19.9% for the 345 W class. 345 W over 1.73 m² equals about 199 W per square meter.

How much energy does one panel produce in Los Angeles or Palmdale?

PVWatts v8 with typical-year weather gives about 578 kWh per year per 345 W panel in Los Angeles and about 633 kWh in Palmdale (20° roof, facing south, 14% system losses).

How much power does it lose on a hot roof?

With γ = −0.360 %/°C, at a 77 °C cell temperature (hottest modeled hour in Palmdale) output is about 18.6% below the STC rating.

How many panels fit on one string?

With the Tesla 1538000-xx-y (max DC 600 V, MPPT from 60 V, datasheet) in Los Angeles the calculator gives 3–13 panels per string (Voc at 2 °C = 43.1 V, Vmp at 74 °C cell = 27 V). Final design must follow the inverter manual and NEC 690.7.

Has this panel been reliability-tested?

Q.PEAK DUO G6+ was a PVEL Top Performer in 2022 (MSS) — a closely related product name.

Sources

  1. California Energy Commission — Solar Equipment Lists, PV Module List, Inverter List (snapshot Oct 7, 2026).
  2. JinkoSolar — datasheet THE MOST DEPENDABLE SOLAR BRAND.
  3. JinkoSolar — manufacturer datasheet “Eagle HC 60M G2 315-335 Watt MONO PERC HALF CELL MODULE”.
  4. Kiwa PVEL — PV Module Reliability Scorecard, Top Performer lists 2016–2026.
  5. RETC — PV Module Index reports 2023–2026.
  6. NLR (formerly NREL) — System Advisor Model CEC inverter library (version 2026.7.3).
  7. NLR (formerly NREL) — PVWatts v8, NSRDB PSM v3 typical-year weather for Los Angeles, Palmdale, Chula Vista, Huntington Beach, Riverside, Santa Clarita.
  8. Inverter datasheets — APsystems (Alt Power System), Enphase, Solis (Ginlong), Tesla (manufacturer documents).
  9. Building permits — Southern California permit portals. Equipment matched from permit descriptions.
  10. Cali-Graf calculations — formulas and inputs are shown next to each calculated value (efficiency from area, temperature-corrected voltages, string sizing, energy estimates).