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Illustration · 128 cells
Solar panelMaxeon Solar Technologies

Maxeon Solar Technologies SPR-X21-470-COM

128 cells. 470 W in the CEC list.

CEC listed · Dec 12, 2022UL 61730
  • Power (STC)470 WCEC nameplate
  • Efficiency≈21.8%calculated from area
  • %/°C Pmax−0.352CEC listing test
  • PTC / STC93.2%PTC 438 W (CEC)

Electrical ratings (STC)

CEC PV Module List (Oct 7, 2026) · Cali-Graf calculation
ModelPmaxVoc, VIsc, AVmp, VImp, AEfficiencyPTCCEC listed
SPR-X21-470-COM470 W91.506.4577.606.06≈21.8%438 WDec 12, 2022
≈ efficiency = Pmax ÷ CEC-listed area 2.16 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−0.352 %/°C
Voc coefficient β−0.293 %/°C
Isc coefficient α+0.031 %/°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
470 W340 W74.68 V × 4.55 A86.4 W92%
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
8
PVEL Scorecards
Maxeon Solar Technologies named Top Performer, 2017–2025
This exact series is not listed in published PVEL Top Performer tables. Results below are for the manufacturer.

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)
97.7 V
Voc when cold
per panel
63 V
Vmp when hot
per panel
6
Max panels / string
max DC 600 V
1
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 Vdatasheet1–6
Solis (Ginlong) S6-EH1P10K-H-US600 V80–520 Vdatasheet2–6
Solis (Ginlong) Solis-1P7.6K-4G-US600 V100–500 Vdatasheet2–6
Qcells Q.VOLT H7.6SX498 V234–498 VCEC test window4–5

Microinverters (one per panel)

MicroinverterRecommended module powerMax DC inputMPPTVoc cold / Vmp hotCheckDC/AC
Enphase IQ8X-80-M-US320–540 W79.5 V43–60 V97.7 / 63 V✗ Not allowed: cold Voc above max input1.24
APsystems (Alt Power System) DS3-L265–570 W60 V28–45 V97.7 / 63 V✗ Not allowed: cold Voc above max input0.6
Enphase IQ8A-72-2-US295–500 W60 V32–45 V97.7 / 63 V✗ Not allowed: cold Voc above max input1.35
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 Angeles1,67678811,8166.08
Palmdale1,83586212,9376.69
Chula Vista1,69679711,9576.11
Huntington Beach1,64377211,5835.89
Riverside1,69679711,9576.21
Santa Clarita1,72481012,1546.28
771Jan772Feb991Mar1,094Apr1,081May1,148Jun1,210Jul1,224Aug1,070Sep944Oct811Nov702DeckWh 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 470 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)
Maxeon Solar Technologies SPR-X21-470-COM470 W≈21.8%−0.35291.56.45brand 8×—
REC Group REC470AA Pure-RX470 W≈23.3%−0.24865.78.95brand 9× (2016–2025)33
Aptos Solar DNA-120-MF10-465W465 W≈21.5%−0.36341.914.07—22
Canadian Solar CS6.1-54TM-465H465 W≥22.8%−0.30839.514.77product 2024, 20259
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 Maxeon Solar Technologies

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

Other series by SoCal permits

SPR-MAX6 · 2SPR-MAX6-xxx-BLKSPR-MAX3SPR-MAX3-xxx-BLKSPR-MAX3-xxx-BLK-RSPR-MAX3-xxx-COM

Questions & answers

How efficient is the Maxeon Solar Technologies SPR-X21-470-COM?

Calculated from the panel area (2.16 m²): about 21.8% for the 470 W class. 470 W over 2.16 m² equals about 218 W per square meter.

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

PVWatts v8 with typical-year weather gives about 788 kWh per year per 470 W panel in Los Angeles and about 862 kWh in Palmdale (20° roof, facing south, 14% system losses).

How much power does it lose on a hot roof?

With γ = −0.352 %/°C, at a 77 °C cell temperature (hottest modeled hour in Palmdale) output is about 18.2% 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 1–6 panels per string (Voc at 2 °C = 97.7 V, Vmp at 74 °C cell = 63 V). Final design must follow the inverter manual and NEC 690.7.

Has this panel been reliability-tested?

This exact series is not in published PVEL Top Performer tables; Maxeon Solar Technologies was named a Top Performer in 8 Scorecards (2017–2025).

Sources

  1. California Energy Commission — Solar Equipment Lists, PV Module List, Inverter List (snapshot Oct 7, 2026).
  2. Aptos Solar — datasheet Legacy Products.
  3. Canadian Solar — datasheet TOPHiKu6 (All-Black) N-type TOPCon Technology CS6.1-54TM-435|440|445|450|455|460|465H.
  4. Kiwa PVEL — PV Module Reliability Scorecard, Top Performer lists 2017–2025.
  5. NLR (formerly NREL) — System Advisor Model CEC inverter library (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).