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Solar panelWaaree

Waaree WSMDB 390

108 half-cut cells, bifacial, black backsheet. Power classes 380–405 W in the CEC list.

CEC listed · Feb 21, 2023UL 61730BifacialPVEL Top Performer 2024
Power class
  • Power (STC)390 WCEC nameplate
  • Efficiency≈20.2%calculated from area
  • %/°C Pmax−0.338CEC listing test
  • PTC / STC94%PTC 367 W (CEC)

Power classes

CEC PV Module List (Oct 7, 2026) · Cali-Graf calculation · 6 models
ModelPmaxVoc, VIsc, AVmp, VImp, AEfficiencyPTCCEC listed
WSMDB-380380 W36.4513.3430.5912.44≈19.7%357 WFeb 21, 2023
WSMDB-385385 W36.5713.4230.7112.55≈19.9%362 WFeb 21, 2023
WSMDB-390390 W36.6913.5030.8212.67≈20.2%367 WFeb 21, 2023
WSMDB-395395 W36.9413.5831.0612.73≈20.5%371 WFeb 21, 2023
WSMDB-400400 W37.0613.6631.1912.84≈20.7%376 WFeb 21, 2023
WSMDB-405405 W37.1813.7331.3112.95≈21.0%381 WFeb 21, 2023
≈ efficiency = Pmax ÷ CEC-listed area 1.93 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−0.338 %/°C
Voc coefficient β−0.254 %/°C
Isc coefficient α+0.032 %/°C
Operating cell temperatureNOCT 43.5 °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
380 W273.3 W28.87 V × 9.47 A71.7 W94%
385 W276.8 W28.99 V × 9.55 A72.7 W94%
390 W280.5 W29.09 V × 9.64 A73.6 W94%
395 W284 W29.32 V × 9.69 A74.6 W94%
400 W287.6 W29.44 V × 9.77 A75.5 W94%
405 W291.2 W29.55 V × 9.85 A76.4 W94%
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
2023, 2024
PVEL Top Performer
this series
1
Tests passed as Top Performer
LID+LETID
5
PVEL Scorecards
Waaree named Top Performer, 2022–2026
2025, 2026
RETC Overall Highest Achiever
Waaree, manufacturer level

PVEL Top Performer tests

YearProductTests
2024WSMDB-xxxLID+LETID
2023WSMDB-AAA (108) (closely related product name)LID+LETID

Tested bill of materials

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

RETC PV Module Index — Waaree

YearRecognition
2024Test Category High Achiever
2025Overall Highest Achiever
2026Overall Highest Achiever; High achievement in performance; High achievement in reliability; Performance discipline high achiever (Temperature coefficient, Iam, Letid); Quality discipline high achiever (BOM verification); Reliability discipline high achiever (Damp heat, Pid, Tc)

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)
38.8 V
Voc when cold
per panel
25.2 V
Vmp when hot
per panel
15
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 Vdatasheet3–15
Solis (Ginlong) S6-EH1P10K-H-US600 V80–520 Vdatasheet4–15
Solis (Ginlong) Solis-1P7.6K-4G-US600 V100–500 Vdatasheet4–15
Qcells Q.VOLT H7.6SX498 V234–498 VCEC test window10–12

Microinverters (one per panel)

MicroinverterRecommended module powerMax DC inputMPPTVoc cold / Vmp hotCheckDC/AC
Enphase IQ8PLUS-72-2-US235–440 W60 V29–45 V38.8 / 25.2 V⚠ Works; below MPPT at peak heat1.34
Enphase IQ8X-80-M-US320–540 W79.5 V43–60 V38.8 / 25.2 V✗ Not a match: module voltage below MPPT range1.03
APsystems (Alt Power System) DS3-L265–570 W60 V28–45 V38.8 / 25.2 V⚠ Works; below MPPT at peak heat0.5
Enphase IQ8M-72-2-US260–460 W60 V30–45 V38.8 / 25.2 V⚠ Works; below MPPT at peak heat1.2
Enphase IQ8A-72-2-US295–500 W60 V32–45 V38.8 / 25.2 V✗ Not a match: module voltage below MPPT range1.12
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 Angeles1,67665411,7666.08
Palmdale1,83571612,8826.69
Chula Vista1,69666111,9066.11
Huntington Beach1,64364111,5345.89
Riverside1,69666111,9066.21
Santa Clarita1,72467212,1026.28
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 390 W panels

CEC PV Module List (Oct 7, 2026) · Qcells datasheet · Kiwa PVEL Scorecard · building permits
PanelPmaxEfficiencyγ Pmax (CEC)Voc, VIsc, APVEL (product / brand)SoCal permits (series)
Waaree WSMDB 390390 W≈20.2%−0.33836.6913.5product 2024—
Qcells Q.PEAK DUO BLK ML-G10+ 390390 W≥19.9%−0.36245.2311.07product 2022, 2023221
JA Solar JAM54S31-390/MR390 W≈20.5%−0.32936.8513.61product 2023, 2024152
REC Group REC390AA Pure390 W≈21.8%−0.25648.610.19brand 9× (2016–2025)66
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 Waaree

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

Other series by SoCal permits

WSMDi · 3BiN-21BiN-01BiN-02BiN-03BiN-05

Questions & answers

How efficient is the Waaree WSMDB 390?

Calculated from the panel area (1.93 m²): about 20.2% for the 390 W class. 390 W over 1.93 m² equals about 202 W per square meter.

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

PVWatts v8 with typical-year weather gives about 654 kWh per year per 390 W panel in Los Angeles and about 716 kWh in Palmdale (20° roof, facing south, 14% system losses).

How much power does it lose on a hot roof?

With γ = −0.338 %/°C, at a 77 °C cell temperature (hottest modeled hour in Palmdale) output is about 17.5% 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 3–15 panels per string (Voc at 2 °C = 38.8 V, Vmp at 74 °C cell = 25.2 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?

WSMDB-xxx was a PVEL Top Performer in 2024 (LID+LETID).

Sources

  1. California Energy Commission — Solar Equipment Lists, PV Module List, Inverter List (snapshot Oct 7, 2026).
  2. Qcells — manufacturer datasheet “Q.PEAK DUO BLK ML-G10+ ENDURING HIGH PERFORMANCE”.
  3. Kiwa PVEL — PV Module Reliability Scorecard, Top Performer lists 2022–2026.
  4. RETC — PV Module Index reports 2024–2026.
  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).