Cali-GrafCali-Graf
For pros Sign in
Illustration · 144 half-cut cells
Solar panelGCL System Integration Technol…

GCL System Integration Technology GCL-M10/72GDF 540

144 half-cut cells, bifacial, glass (dual-glass module). Power classes 530–555 W in the CEC list.

CEC listed · Jan 23, 2023UL 61730BifacialPVEL Top Performer 2024
Power class
  • Power (STC)540 WCEC nameplate
  • Efficiency≈21.1%calculated from area
  • %/°C Pmax−0.332CEC listing test
  • PTC / STC93.5%PTC 505 W (CEC)

Power classes

CEC PV Module List (Oct 7, 2026) · Cali-Graf calculation · 6 models
ModelPmaxVoc, VIsc, AVmp, VImp, AEfficiencyPTCCEC listed
GCL-M10/72GDF530530 W48.6813.6840.9612.94≈20.7%495 WJan 23, 2023
GCL-M10/72GDF535535 W48.9613.7341.2212.98≈20.9%500 WJan 23, 2023
GCL-M10/72GDF540540 W49.2413.7841.4513.03≈21.1%505 WJan 23, 2023
GCL-M10/72GDF545545 W49.5213.8341.7013.07≈21.3%510 WJan 23, 2023
GCL-M10/72GDF550550 W49.8013.8841.9313.12≈21.5%514 WJan 23, 2023
GCL-M10/72GDF555555 W50.0813.9342.1813.16≈21.7%519 WJan 23, 2023
≈ efficiency = Pmax ÷ CEC-listed area 2.56 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−0.332 %/°C
Voc coefficient β−0.259 %/°C
Isc coefficient α+0.042 %/°C
Operating cell temperatureNOCT 45.7 °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
530 W397.3 W38.41 V × 10.34 A103 W97%
535 W401 W38.65 V × 10.38 A104 W97%
540 W404.8 W38.87 V × 10.42 A105 W97%
545 W408.5 W39.1 V × 10.45 A105.9 W97%
550 W412.3 W39.32 V × 10.49 A106.9 W97%
555 W416.1 W39.55 V × 10.52 A107.9 W97%
Pmax = Vmp × Imp from the CEC listing; low-light efficiency = Pmax at 200 W/m² ÷ (20% of STC Pmax).

Certifications

CEC PV Module List (Oct 7, 2026)
UL 61730IEC 61215

Independent reliability testing

Kiwa PVEL Scorecard
2024
PVEL Top Performer
this series
4
Tests passed as Top Performer
LID+LETID, MSS, PID, TC
8
PVEL Scorecards
GCL System Integration Technology named Top Performer, 2017–2026

PVEL Top Performer tests

YearProductTests
2024GCL-M10/72GDFxxxLID+LETIDMSSPIDTC

Tested bill of materials

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

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)
52.2 V
Voc when cold
per panel
33.8 V
Vmp when hot
per panel
11
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 Vdatasheet2–11
Solis (Ginlong) S6-EH1P10K-H-US600 V80–520 Vdatasheet3–11
Solis (Ginlong) Solis-1P7.6K-4G-US600 V100–500 Vdatasheet3–11
Qcells Q.VOLT H7.6SX498 V234–498 VCEC test window7–9

Microinverters (one per panel)

MicroinverterRecommended module powerMax DC inputMPPTVoc cold / Vmp hotCheckDC/AC
Enphase IQ8X-80-M-US320–540 W79.5 V43–60 V52.2 / 33.8 V✗ Not a match: module voltage below MPPT range1.42
APsystems (Alt Power System) DS3-L265–570 W60 V28–45 V52.2 / 33.8 V✓ Within range0.69
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 Angeles1,67690511,7666.08
Palmdale1,83599112,8826.69
Chula Vista1,69691611,9066.11
Huntington Beach1,64388711,5345.89
Riverside1,69691611,9066.21
Santa Clarita1,72493112,1026.28
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 540 W panels

CEC PV Module List (Oct 7, 2026) · Kiwa PVEL Scorecard · datasheets · building permits
PanelPmaxEfficiencyγ Pmax (CEC)Voc, VIsc, APVEL (product / brand)SoCal permits (series)
GCL System Integration Technology GCL-M10/72GDF 540540 W≈21.1%−0.33249.2413.78product 2024—
JA Solar JAM72D30-540/MB540 W≈21.4%−0.33049.613.86product 2023, 20243
Canadian Solar CS6W-540MB-AG540 W≈21%−0.32449.213.9product 20241
LONGi LR5-72HBD-540M540 W≥21.1%−0.35449.513.85product 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.

Questions & answers

How efficient is the GCL System Integration Technology GCL-M10/72GDF 540?

Calculated from the panel area (2.56 m²): about 21.1% for the 540 W class. 540 W over 2.56 m² equals about 211 W per square meter.

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

PVWatts v8 with typical-year weather gives about 905 kWh per year per 540 W panel in Los Angeles and about 991 kWh in Palmdale (20° roof, facing south, 14% system losses).

How much power does it lose on a hot roof?

With γ = −0.332 %/°C, at a 77 °C cell temperature (hottest modeled hour in Palmdale) output is about 17.2% 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 2–11 panels per string (Voc at 2 °C = 52.2 V, Vmp at 74 °C cell = 33.8 V). Final design must follow the inverter manual and NEC 690.7.

Does it work with APsystems (Alt Power System) DS3-L microinverters?

Voltage check against the APsystems (Alt Power System) datasheet: Voc when cold 52.2 V vs max input 60 V; Vmp when hot 33.8 V vs MPPT low 28 V; recommended module power 265–570 W. Confirm on the microinverter maker’s compatibility list.

Is it bifacial?

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

Has this panel been reliability-tested?

GCL-M10/72GDFxxx was a PVEL Top Performer in 2024 (LID+LETID, MSS, PID, TC).

Sources

  1. California Energy Commission — Solar Equipment Lists, PV Module List, Inverter List (snapshot Oct 7, 2026).
  2. Canadian Solar — datasheet BiHiKu6 BIFACIAL MONO PERC CS6W-520|525|530|535|540|545|550MB-AG.
  3. LONGi — manufacturer datasheet “LR5-72HBD Suitable for distributed projects Advanced module technology delivers superior”.
  4. Kiwa PVEL — PV Module Reliability Scorecard, Top Performer lists 2017–2026.
  5. NLR (formerly NREL) — System Advisor Model CEC module and inverter libraries (version 2026.7.3).
  6. NLR (formerly NREL) — PVWatts v8, NSRDB PSM v3 typical-year weather for Los Angeles, Palmdale, Chula Vista, Huntington Beach, Riverside, Santa Clarita.
  7. Inverter datasheets — APsystems (Alt Power System), Enphase, Solis (Ginlong), Tesla (manufacturer documents).
  8. Building permits — Southern California permit portals. Equipment matched from permit descriptions.
  9. Cali-Graf calculations — formulas and inputs are shown next to each calculated value (efficiency from area, temperature-corrected voltages, string sizing, energy estimates).