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70.7″ · 1,795 mm
39″ · 990 mm wide · 1.5″ (38 mm) frame · 41.9 lb (19 kg)
Solar panelSilfab Solar

Silfab Solar SIL-370BK

66 cells, IBC. Power classes 360–380 W in the CEC list.

CEC listed · Feb 11, 2021UL 6173025-yr product + 30-yr performance warrantyIBCInstalled in 10 SoCal permits
Power class
  • Power (STC)370 WCEC nameplate
  • Efficiency≈20.8%calculated from area
  • %/°C Pmax−0.38CEC test: −0.435
  • Output at year 3082.6%performance warranty

Power classes

CEC PV Module List (Oct 7, 2026) · Cali-Graf calculation · 5 models
ModelPmaxVoc, VIsc, AVmp, VImp, AEfficiencyPTCCEC listed
SIL-360BK360 W44.3910.1537.789.53≈20.3%332 WFeb 11, 2021
SIL-365BK365 W44.5710.2438.079.61≈20.5%340 WFeb 11, 2021
SIL-370BK370 W44.7610.3338.349.69≈20.8%341 WFeb 11, 2021
SIL-375BK375 W44.9410.4138.519.76≈21.1%350 WJul 12, 2021
SIL-380BK380 W45.1310.5038.889.79≈21.4%354 WJul 12, 2021
≈ efficiency = Pmax ÷ panel area 1.777 m² (datasheet size).

Build & dimensions

Silfab Solar datasheet · Cali-Graf calculation · CEC PV Module List (Oct 7, 2026)

Heat & cold behaviour

Silfab Solar datasheet · CEC PV Module List (Oct 7, 2026) · Cali-Graf calculation
DatasheetCEC listing test
Pmax coefficient γ−0.38 %/°C−0.435 %/°C
Voc coefficient β−0.28 %/°C−0.303 %/°C
Isc coefficient α+0.05 %/°C+0.011 %/°C
Vmp coefficient≈ −0.42 %/°C—
Operating cell temperatureNMOT 43.5 °CNOCT 44 °C
Vmp coefficient ≈ γ − α (datasheet); used only for the hot-roof voltage estimate.

At normal operating conditions (NOCT, 800 W/m²) — datasheet

ClassPmax, WVoc, VIsc, AVmp, VImp, A
370 W277.842.018.3235.907.74

Away from lab conditions — CEC listing test points

ClassPmax at NOCTVmp × Imp at NOCTPmax at 200 W/m²Low-light efficiency vs STC
360 W256.7 W33.65 V × 7.63 A67.6 W94%
365 W271.5 W34.91 V × 7.78 A70.6 W97%
370 W264.9 W34.15 V × 7.76 A69.8 W94%
375 W278.9 W35.32 V × 7.9 A72.5 W97%
380 W282.5 W35.65 V × 7.92 A73.5 W97%
Pmax = Vmp × Imp from the CEC listing; low-light efficiency = Pmax at 200 W/m² ÷ (20% of STC Pmax).

Electrical & strength ratings

Silfab Solar datasheet
Packaging: 26 per pallet

Certifications

CEC PV Module List (Oct 7, 2026) · Silfab Solar datasheet
UL 61730UL 1703IEC 61215IEC 61730IEC 61701IEC 62716ISO 9001

Warranty & degradation

Silfab Solar datasheet

Independent reliability testing

Kiwa PVEL Scorecard · RETC PV Module Index
7
PVEL Scorecards
Silfab Solar named Top Performer, 2017–2025
4
RETC PV Module Index
Silfab Solar recognized 2023–2026
This exact series is not listed in published PVEL Top Performer tables. Results below are for the manufacturer.

RETC PV Module Index — Silfab Solar

YearRecognition
2023High Achievement in Performance (Ptc-to-stc ratio, LeTID RESISTANCE, Module efficiency)
2024High Achievement in Performance
2025Performance High Achiever
2026Performance discipline high achiever (Lid); Quality discipline high achiever (BOM verification); Reliability discipline high achiever (Pid, Sdml); Test Category High Achiever

Inverter compatibility & string sizing

Silfab Solar datasheet · Cali-Graf calculation · NLR PVWatts v8 · CEC PV Module List (Oct 7, 2026) · inverter datasheets · NLR SAM inverter library · CEC Grid Support Inverter List (Oct 7, 2026)
47.6 V
Voc when cold
per panel
30.4 V
Vmp when hot
per panel
12
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.

String inverters most named in SoCal permits

InverterMax DC inputMPPTWindow sourcePanels per string
Tesla 1538000-xx-y600 V60–480 Vdatasheet2–12
Solis (Ginlong) S6-EH1P10K-H-US600 V80–520 Vdatasheet3–12
Solis (Ginlong) Solis-1P7.6K-4G-US600 V100–500 Vdatasheet4–12
Qcells Q.VOLT H7.6SX498 V234–498 VCEC test window8–10

Microinverters (one per panel)

MicroinverterRecommended module powerMax DC inputMPPTVoc cold / Vmp hotCheckDC/AC
Enphase IQ8PLUS-72-2-US235–440 W60 V29–45 V47.6 / 30.4 V✓ Within range1.28
Enphase IQ8X-80-M-US320–540 W79.5 V43–60 V47.6 / 30.4 V✗ Not a match: module voltage below MPPT range0.97
APsystems (Alt Power System) DS3-L265–570 W60 V28–45 V47.6 / 30.4 V✓ Within range0.47
Enphase IQ8M-72-2-US260–460 W60 V30–45 V47.6 / 30.4 V✓ Within range1.14
Enphase IQ8A-72-2-US295–500 W60 V32–45 V47.6 / 30.4 V⚠ Works; below MPPT at peak heat1.06
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 Angeles1,67662011,7826.08
Palmdale1,83567912,9006.69
Chula Vista1,69662811,9236.11
Huntington Beach1,64360811,5505.89
Riverside1,69662811,9236.21
Santa Clarita1,72463812,1206.28
769Jan770Feb988Mar1,091Apr1,078May1,145Jun1,206Jul1,220Aug1,067Sep941Oct809Nov700DeckWh 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.

Who installs SIL-xxxBK panels in SoCal

building permits
10
Permits naming this series
Sep 2021 – Jan 2024
1
Jurisdictions so far
LA County (unincorp.) (10)

Permits over time

1Q3 ’211Q4 ’212Q1 ’221Q2 ’220Q3 ’221Q4 ’220Q1 ’232Q2 ’230Q3 ’231Q4 ’231Q1 ’24permits per quarter

Power class named in permit

370 W
6
380 W
4

Typical system

median 6.3 kW, 20 panels (n = 6)

Only installer and ZIP level is shown — no homeowner names, street addresses or permit numbers. Permits from LA County (unincorp.) come without a contractor license, so they count toward totals but not toward installers. Counts grow as more permit portals are loaded.

Installed together with

building permits

Microinverters

Enphase IQ8+
4

Inverters

SolarEdge (model not specified)
2
SolarEdge SE…H (HD-Wave)
2

Optimizers

SolarEdge Power Optimizer
3
Number of permits naming both this panel series and the product; 10 of 10 permits list other equipment.

Compare with similar 370 W panels

CEC PV Module List (Oct 7, 2026) · Kiwa PVEL Scorecard · Canadian Solar datasheet · building permits
PanelPmaxEfficiencyγ Pmax (CEC)Voc, VIsc, APVEL (product / brand)SoCal permits (series)
Silfab Solar SIL-370BK370 W≈20.8%−0.43544.7610.33brand 7×10
LONGi LR4-60HPB-370M370 W≈20.9%−0.33941.211.5product 2021, 2022193
Canadian Solar CS3N-375MS {Blk}375 W≈19%−0.34243.511.2product 202346
REC Group REC370AA370 W≈21.9%−0.25844.110.55brand 9× (2016–2025)30
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.

Documents

manufacturer documents

About Silfab Solar

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

Other series by SoCal permits

SIL-xxxQD · 39SIL-xxxHC+ · 28SIL-xxxHC · 9SIL-xxxNX · 6SIL-xxxBG · 5SIL-xxxNL · 2

Questions & answers

How efficient is the Silfab Solar SIL-370BK?

Calculated from the panel area (1.78 m²): about 20.8% for the 370 W class. 370 W over 1.78 m² equals about 208 W per square meter.

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

PVWatts v8 with typical-year weather gives about 620 kWh per year per 370 W panel in Los Angeles and about 679 kWh in Palmdale (20° roof, facing south, 14% system losses).

How much power does it lose on a hot roof?

With γ = −0.38 %/°C, at a 77 °C cell temperature (hottest modeled hour in Palmdale) output is about 19.5% 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 2–12 panels per string (Voc at 2 °C = 47.6 V, Vmp at 74 °C cell = 30.4 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 47.6 V vs max input 60 V; Vmp when hot 30.4 V vs MPPT low 29 V; recommended module power 235–440 W. Confirm on the microinverter maker’s compatibility list.

What does the warranty cover?

25 years on the product and 30 years on performance: at least 82.6% after 30 years (manufacturer datasheet).

How big and heavy is it?

70.7 × 39 × 1.5 in (1,795 × 990 × 38 mm), 41.9 lb (19 kg).

Has this panel been reliability-tested?

This exact series is not in published PVEL Top Performer tables; Silfab Solar was named a Top Performer in 7 Scorecards (2017–2025).

Sources

  1. California Energy Commission — Solar Equipment Lists, PV Module List, Inverter List (snapshot Oct 7, 2026).
  2. Silfab Solar — datasheet SIL-370 BK NOT JUST ANOTHER S O L A R PA N E L ..
  3. Canadian Solar — manufacturer datasheet “HiKu Mono PERC CS3N-400|405|410|415|420|425MS MORE POWER”.
  4. Silfab Solar — document library on the manufacturer’s website (links above).
  5. Kiwa PVEL — PV Module Reliability Scorecard, Top Performer lists 2017–2025.
  6. RETC — PV Module Index reports 2023–2026.
  7. NLR (formerly NREL) — System Advisor Model CEC inverter library (version 2026.7.3).
  8. NLR (formerly NREL) — PVWatts v8, NSRDB PSM v3 typical-year weather for Los Angeles, Palmdale, Chula Vista, Huntington Beach, Riverside, Santa Clarita.
  9. Inverter datasheets — APsystems (Alt Power System), Enphase, Solis (Ginlong), Tesla (manufacturer documents).
  10. Building permits — Los Angeles County Public Works (EPIC-LA, unincorporated areas) (Sep 2021 – Jan 2024). Equipment matched from permit descriptions by model number.
  11. Cali-Graf calculations — formulas and inputs are shown next to each calculated value (efficiency from area, temperature-corrected voltages, string sizing, energy estimates).