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Solar panelOptivolt Labs

Optivolt Labs OPT10M440B

108 cells. Power classes 435–450 W in the CEC list.

CEC listed · Feb 23, 2026UL 61730
Power class
  • Power (STC)440 WCEC nameplate
  • Efficiency≈22.7%calculated from area
  • %/°C Pmax−0.400CEC listing test
  • PTC / STC91.3%PTC 402 W (CEC)

Power classes

CEC PV Module List (Oct 7, 2026) · Cali-Graf calculation · 4 models
ModelPmaxVoc, VIsc, AVmp, VImp, AEfficiencyPTCCEC listed
OPT10M435B435 W38.7013.7633.4013.02≈22.4%406 WFeb 23, 2026
OPT10M440B440 W39.6213.9133.3813.19≈22.7%402 WFeb 23, 2026
OPT10M445B445 W39.6914.0233.4413.31≈22.9%407 WFeb 23, 2026
OPT10M450B450 W39.7514.1433.5113.44≈23.2%411 WFeb 23, 2026
≈ efficiency = Pmax ÷ CEC-listed area 1.94 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−0.400 %/°C
Voc coefficient β−0.280 %/°C
Isc coefficient α+0.060 %/°C
Operating cell temperatureNOCT 48.5 °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
435 W313 W31.3 V × 10 A78.7 W90%
440 W273.3 W27.4 V × 9.97 A78.3 W89%
445 W276.4 W27.46 V × 10.07 A79.2 W89%
450 W279.5 W27.51 V × 10.16 A80.1 W89%
Pmax = Vmp × Imp from the CEC listing; low-light efficiency = Pmax at 200 W/m² ÷ (20% of STC Pmax).

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)
42.2 V
Voc when cold
per panel
25.9 V
Vmp when hot
per panel
14
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 Vdatasheet3–14
Solis (Ginlong) S6-EH1P10K-H-US600 V80–520 Vdatasheet4–14
Solis (Ginlong) Solis-1P7.6K-4G-US600 V100–500 Vdatasheet4–14
Qcells Q.VOLT H7.6SX498 V234–498 VCEC test window10–11

Microinverters (one per panel)

MicroinverterRecommended module powerMax DC inputMPPTVoc cold / Vmp hotCheckDC/AC
Enphase IQ8PLUS-72-2-US235–440 W60 V29–45 V42.2 / 25.9 V⚠ Works; below MPPT at peak heat1.52
Enphase IQ8X-80-M-US320–540 W79.5 V43–60 V42.2 / 25.9 V✗ Not a match: module voltage below MPPT range1.16
APsystems (Alt Power System) DS3-L265–570 W60 V28–45 V42.2 / 25.9 V⚠ Works; below MPPT at peak heat0.56
Enphase IQ8M-72-2-US260–460 W60 V30–45 V42.2 / 25.9 V⚠ Works; below MPPT at peak heat1.35
Enphase IQ8A-72-2-US295–500 W60 V32–45 V42.2 / 25.9 V⚠ Works; below MPPT at peak heat1.26
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 Angeles1,67673711,7996.08
Palmdale1,83580712,9186.69
Chula Vista1,69674611,9406.11
Huntington Beach1,64372311,5675.89
Riverside1,69674611,9406.21
Santa Clarita1,72475912,1376.28
770Jan771Feb989Mar1,093Apr1,079May1,147Jun1,208Jul1,222Aug1,069Sep943Oct810Nov701DeckWh 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 440 W panels

CEC PV Module List (Oct 7, 2026) · datasheets · Kiwa PVEL Scorecard · building permits
PanelPmaxEfficiencyγ Pmax (CEC)Voc, VIsc, AWarrantyPVEL (product / brand)SoCal permits (series)
Optivolt Labs OPT10M440B440 W≈22.7%−0.40039.6213.91———
Qcells Q.TRON BLK M-G2+ 440440 W≥22.5%−0.27639.8813.925 / 25 yrbrand 11× (2016–2026)40
Silfab Solar SIL-440QD440 W≈22.6%−0.29438.9714.2525 / 30 yrbrand 7× (2017–2025)39
Hyundai Energy Solutions HiN-T440NF(BK)440 W≈22.7%−0.29838.814.3925 / 30 yrbrand 5× (2017–2025)37
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 Optivolt Labs OPT10M440B?

Calculated from the panel area (1.94 m²): about 22.7% for the 440 W class. 440 W over 1.94 m² equals about 227 W per square meter.

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

PVWatts v8 with typical-year weather gives about 737 kWh per year per 440 W panel in Los Angeles and about 807 kWh in Palmdale (20° roof, facing south, 14% system losses).

How much power does it lose on a hot roof?

With γ = −0.400 %/°C, at a 77 °C cell temperature (hottest modeled hour in Palmdale) output is about 20.7% 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 3–14 panels per string (Voc at 2 °C = 42.2 V, Vmp at 74 °C cell = 25.9 V). Final design must follow the inverter manual and NEC 690.7.

Sources

  1. California Energy Commission — Solar Equipment Lists, PV Module List, Inverter List (snapshot Oct 7, 2026).
  2. Qcells — manufacturer datasheet “Q.TRON BLK M-G2+ SERIES 415–440 Wp”.
  3. Silfab Solar — datasheet NTC SIL-420 QD CELL TECHNOLOGY.
  4. Hyundai Energy Solutions — datasheet [US] NF(BK)(HiN) Series (N TOPCon Bifacial) 435~445W.
  5. Kiwa PVEL — PV Module Reliability Scorecard, Top Performer lists.
  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).