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Qcells Q.PEAK DUO XL-G11S.B3/BFG 585

156 half-cut cells, bifacial, glass (dual-glass module). Power classes 575–600 W in the CEC list.

CEC listed · Jul 1, 2026UL 61730Bifacial
Power class
  • Power (STC)585 WCEC nameplate
  • Efficiency≈21.5%calculated from area
  • %/°C Pmax−0.348CEC listing test
  • PTC / STC93.3%PTC 546 W (CEC)

Power classes

CEC PV Module List (Oct 7, 2026) · Cali-Graf calculation · 6 models
ModelPmaxVoc, VIsc, AVmp, VImp, AEfficiencyPTCCEC listed
Q.PEAK DUO XL-G11S.B3/BFG 575575 W53.5013.6744.3012.98≈21.1%536 WJul 1, 2026
Q.PEAK DUO XL-G11S.B3/BFG 580580 W53.6013.6944.5013.03≈21.3%541 WJul 1, 2026
Q.PEAK DUO XL-G11S.B3/BFG 585585 W53.6013.7244.8013.07≈21.5%546 WJul 1, 2026
Q.PEAK DUO XL-G11S.B3/BFG 590590 W53.6013.7445.0013.12≈21.7%551 WJul 1, 2026
Q.PEAK DUO XL-G11S.B3/BFG 595595 W53.6013.7745.2013.17≈21.9%555 WJul 1, 2026
Q.PEAK DUO XL-G11S.B3/BFG 600600 W53.7013.8045.3013.25≈22.1%560 WJul 1, 2026
≈ efficiency = Pmax ÷ CEC-listed area 2.72 m².

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−0.348 %/°C
Voc coefficient β−0.261 %/°C
Isc coefficient α+0.034 %/°C
Operating cell temperatureNOCT 45.5 °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
575 W426.4 W41.8 V × 10.2 A109.9 W96%
580 W431.1 W42.1 V × 10.24 A110.9 W96%
585 W434.4 W42.3 V × 10.27 A111.9 W96%
590 W438.2 W42.5 V × 10.31 A112.9 W96%
595 W441.9 W42.7 V × 10.35 A113.9 W96%
600 W445.5 W42.8 V × 10.41 A115.1 W96%
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
11
PVEL Scorecards
Qcells named Top Performer, 2016–2026
2023, 2026
RETC Overall Highest Achiever
Qcells, manufacturer level
This exact series is not listed in published PVEL Top Performer tables. Results below are for the manufacturer.

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)
56.8 V
Voc when cold
per panel
36.4 V
Vmp when hot
per panel
10
Max panels / string
max DC 600 V
2
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 Vdatasheet2–10
Solis (Ginlong) S6-EH1P10K-H-US600 V80–520 Vdatasheet3–10
Solis (Ginlong) Solis-1P7.6K-4G-US600 V100–500 Vdatasheet3–10
Qcells Q.VOLT H7.6SX498 V234–498 VCEC test window7–8

Microinverters (one per panel)

No microinverter in the reference set lists this power class in its recommended module power range.
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 Angeles1,67698011,7666.08
Palmdale1,8351,07312,8826.69
Chula Vista1,69699211,9066.11
Huntington Beach1,64396111,5345.89
Riverside1,69699211,9066.21
Santa Clarita1,7241,00912,1026.28
768Jan769Feb986Mar1,090Apr1,076May1,144Jun1,205Jul1,219Aug1,066Sep940Oct808Nov699DeckWh 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.

Compare with similar 585 W panels

CEC PV Module List (Oct 7, 2026) · Kiwa PVEL Scorecard · building permits
PanelPmaxEfficiencyγ Pmax (CEC)Voc, VIsc, APVEL (product / brand)SoCal permits (series)
Qcells Q.PEAK DUO XL-G11S.B3/BFG 585585 W≈21.5%−0.34853.613.72brand 11×—
VSUN (Vietnam Sunergy) VSUN585N-144MH585 W≈22.7%−0.30952.2513.88brand 6× (2021–2026)1
Phono Solar PS585M8GFH-24/TNH585 W≈22.9%−0.29352.913.72product 2024, 20251
ZNShine Solar ZXM7-UHLDD144-585/N585 W≈22.9%−0.28151.714.41product 2024, 2025, 20261
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 XL-G11S.B3/BFG 585?

Calculated from the panel area (2.72 m²): about 21.5% for the 585 W class. 585 W over 2.72 m² equals about 215 W per square meter.

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

PVWatts v8 with typical-year weather gives about 980 kWh per year per 585 W panel in Los Angeles and about 1,073 kWh in Palmdale (20° roof, facing south, 14% system losses).

How much power does it lose on a hot roof?

With γ = −0.348 %/°C, at a 77 °C cell temperature (hottest modeled hour in Palmdale) output is about 18% 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 2–10 panels per string (Voc at 2 °C = 56.8 V, Vmp at 74 °C cell = 36.4 V). Final design must follow the inverter manual and NEC 690.7.

Is it bifacial?

Yes. Rear gain depends on mounting height and ground reflectance.

Has this panel been reliability-tested?

This exact series is not in published PVEL Top Performer tables; Qcells was named a Top Performer in 11 Scorecards (2016–2026). RETC named Qcells Overall Highest Achiever in 2023, 2026.

Sources

  1. California Energy Commission — Solar Equipment Lists, PV Module List, Inverter List (snapshot Oct 7, 2026).
  2. Kiwa PVEL — PV Module Reliability Scorecard, Top Performer lists 2016–2026.
  3. RETC — PV Module Index reports 2023–2026.
  4. NLR (formerly NREL) — System Advisor Model CEC inverter library (version 2026.7.3).
  5. NLR (formerly NREL) — PVWatts v8, NSRDB PSM v3 typical-year weather for Los Angeles, Palmdale, Chula Vista, Huntington Beach, Riverside, Santa Clarita.
  6. Inverter datasheets — Solis (Ginlong), Tesla (manufacturer documents).
  7. Building permits — Southern California permit portals. Equipment matched from permit descriptions.
  8. Cali-Graf calculations — formulas and inputs are shown next to each calculated value (efficiency from area, temperature-corrected voltages, string sizing, energy estimates).