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Solar panelKOSOL ENERGIE

KOSOL ENERGIE KE375MX

144 half-cut cells. Power classes 355–400 W in the CEC list.

CEC listed · Mar 1, 2022UL 61730
Power class
  • Power (STC)375 WCEC nameplate
  • Efficiency≈18.8%calculated from area
  • %/°C Pmax−0.336CEC listing test
  • PTC / STC93.2%PTC 350 W (CEC)

Power classes

CEC PV Module List (Oct 7, 2026) · Cali-Graf calculation · 10 models
ModelPmaxVoc, VIsc, AVmp, VImp, AEfficiencyPTCCEC listed
KE355MX355 W46.909.6838.609.21≈17.8%331 WMar 1, 2022
KE360MX360 W47.209.7338.809.28≈18.0%335 WMar 1, 2022
KE365MX365 W47.609.8339.009.37≈18.2%340 WMar 1, 2022
KE370MX370 W47.609.8839.209.44≈18.5%345 WMar 1, 2022
KE375MX375 W47.809.9339.409.52≈18.8%350 WMar 1, 2022
KE380MX380 W48.009.9939.609.60≈19.0%354 WMar 1, 2022
KE385MX385 W48.5010.0340.109.61≈19.2%359 WMar 1, 2022
KE390MX390 W49.7010.0840.509.64≈19.5%364 WMar 1, 2022
KE395MX395 W50.1010.1340.809.69≈19.8%369 WMar 1, 2022
KE400MX400 W51.0310.1841.169.72≈20.0%374 WMar 1, 2022
≈ efficiency = Pmax ÷ CEC-listed area 2 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−0.336 %/°C
Voc coefficient β−0.258 %/°C
Isc coefficient α+0.031 %/°C
Operating cell temperatureNOCT 45.4 °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
355 W255.6 W36.01 V × 7.1 A66 W93%
360 W258.9 W36.19 V × 7.15 A66.8 W93%
365 W262.8 W36.38 V × 7.22 A67.8 W93%
370 W266.1 W36.57 V × 7.28 A68.7 W93%
375 W269.7 W36.75 V × 7.34 A69.6 W93%
380 W273.4 W36.94 V × 7.4 A70.6 W93%
385 W277.1 W37.41 V × 7.41 A71.5 W93%
390 W280.7 W37.78 V × 7.43 A72.5 W93%
395 W284.3 W38.06 V × 7.47 A73.4 W93%
400 W287.7 W38.4 V × 7.49 A74.3 W93%
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)
50.6 V
Voc when cold
per panel
32.3 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 Vdatasheet4–11
Qcells Q.VOLT H7.6SX498 V234–498 VCEC test window8–9

Microinverters (one per panel)

MicroinverterRecommended module powerMax DC inputMPPTVoc cold / Vmp hotCheckDC/AC
Enphase IQ8PLUS-72-2-US235–440 W60 V29–45 V50.6 / 32.3 V✓ Within range1.29
Enphase IQ8X-80-M-US320–540 W79.5 V43–60 V50.6 / 32.3 V✗ Not a match: module voltage below MPPT range0.99
APsystems (Alt Power System) DS3-L265–570 W60 V28–45 V50.6 / 32.3 V✓ Within range0.48
Enphase IQ8M-72-2-US260–460 W60 V30–45 V50.6 / 32.3 V✓ Within range1.15
Enphase IQ8A-72-2-US295–500 W60 V32–45 V50.6 / 32.3 V✓ Within range1.07
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 Angeles1,67662811,9426.08
Palmdale1,83568813,0746.69
Chula Vista1,69663612,0846.11
Huntington Beach1,64361611,7065.89
Riverside1,69663612,0846.21
Santa Clarita1,72464612,2846.28
779Jan780Feb1,001Mar1,106Apr1,092May1,161Jun1,223Jul1,237Aug1,082Sep954Oct820Nov710DeckWh 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 375 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)
KOSOL ENERGIE KE375MX375 W≈18.8%−0.33647.89.93——
Qcells Q.PEAK DUO BLK ML-G10+ 380380 W≈19.4%−0.36245.1611.01product 2022, 2023221
LONGi LR4-60HPB-370M370 W≈20.9%−0.33941.211.5product 2021, 2022193
REC Group REC380AA Pure380 W≈21.2%−0.25648.410.17brand 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.

Questions & answers

How efficient is the KOSOL ENERGIE KE375MX?

Calculated from the panel area (2 m²): about 18.8% for the 375 W class. 375 W over 2 m² equals about 188 W per square meter.

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

PVWatts v8 with typical-year weather gives about 628 kWh per year per 375 W panel in Los Angeles and about 688 kWh in Palmdale (20° roof, facing south, 14% system losses).

How much power does it lose on a hot roof?

With γ = −0.336 %/°C, at a 77 °C cell temperature (hottest modeled hour in Palmdale) output is about 17.4% 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 = 50.6 V, Vmp at 74 °C cell = 32.3 V). Final design must follow the inverter manual and NEC 690.7.

Does it work with Enphase IQ8PLUS-72-2-US microinverters?

Voltage check against the Enphase datasheet: Voc when cold 50.6 V vs max input 60 V; Vmp when hot 32.3 V vs MPPT low 29 V; recommended module power 235–440 W. Confirm on the microinverter maker’s compatibility list.

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.
  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 — APsystems (Alt Power System), Enphase, 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).