Illustration · 144 half-cut cells

Solar panelJA Solar

JA Solar JAM72S20-450/MR

Name: JA Solar JAM72S20-450/MR
Brand: JA Solar

144 half-cut cells. Power classes 440–460 W in the CEC list.

CEC listed · Jun 21, 2021UL 61730

Power class

Power (STC)450 WCEC nameplate
Efficiency≈20.7%calculated from area
%/°C Pmax−0.335CEC listing test
PTC / STC93.7%PTC 422 W (CEC)

Power classes

CEC PV Module List (Oct 7, 2026) · Cali-Graf calculation · 5 models

Model	Pmax	Voc, V	Isc, A	Vmp, V	Imp, A	Efficiency	PTC	CEC listed
JAM72S20-440/MR	440 W	49.40	11.28	40.90	10.76	≈20.3%	412 W	Jun 21, 2021
JAM72S20-445/MR	445 W	49.56	11.32	41.21	10.80	≈20.5%	417 W	Jun 21, 2021
JAM72S20-450/MR	450 W	49.70	11.36	41.52	10.84	≈20.7%	422 W	Jun 21, 2021
JAM72S20-455/MR	455 W	49.85	11.41	41.82	10.88	≈21.0%	427 W	Jun 21, 2021
JAM72S20-460/MR	460 W	50.01	11.45	42.13	10.92	≈21.2%	432 W	Jun 21, 2021

≈ efficiency = Pmax ÷ CEC-listed area 2.17 m².

Build & dimensions

CEC PV Module List (Oct 7, 2026)

Module area2.17 m² (23.4 ft²)CEC-listed area
Cells144 half-cut cells
Back coverWhite backsheet

Heat & cold behaviour

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

	CEC listing test
Pmax coefficient γ	−0.335 %/°C
Voc coefficient β	−0.265 %/°C
Isc coefficient α	+0.035 %/°C
Operating cell temperature	NOCT 44.6 °C

Vmp coefficient ≈ γ − α (CEC); used only for the hot-roof voltage estimate.

Away from lab conditions — CEC listing test points

Class	Pmax at NOCT	Vmp × Imp at NOCT	Pmax at 200 W/m²	Low-light efficiency vs STC
440 W	326.5 W	38.45 V × 8.49 A	82.7 W	94%
445 W	330.2 W	38.74 V × 8.52 A	83.7 W	94%
450 W	333.9 W	39.03 V × 8.56 A	84.6 W	94%
455 W	337.6 W	39.32 V × 8.59 A	85.5 W	94%
460 W	341.3 W	39.61 V × 8.62 A	86.5 W	94%

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

PVEL Scorecards

JA Solar named Top Performer, 2014–2026

2023, 2024, 2025, 2026

RETC Overall Highest Achiever

JA Solar, manufacturer level

This exact series is not listed in published PVEL Top Performer tables. Results below are for the manufacturer.

RETC PV Module Index — JA Solar

Year	Recognition
2023	Overall Highest Achiever; High Achievement in Performance (Ptc-to-stc ratio, Pan file performance, Module efficiency, LeTID RESISTANCE); High Achievement in Quality (Hail durability test, Thresher test); High Achievement in Reliability (Thermal cycle test, SDML, Pid resistance, Damp heat test)
2024	Overall Highest Achiever
2025	Overall Highest Achiever
2026	Overall Highest Achiever; High achievement in performance; High achievement in reliability; Performance discipline high achiever (Conversion efficiency, Iam, Letid, Lid, PAN file, PTC-to-STC, Temperature coefficient); Quality discipline high achiever (BOM verification); Reliability discipline high achiever (Damp heat, Pid, Sdml, 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)

CityColdest air, °CHottest cell, °CString inverter

52.7 V

Voc when cold

per panel

34 V

Vmp when hot

per panel

Max panels / string

max DC 600 V

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

Inverter	Max DC input	MPPT	Window source	Panels per string
Tesla 1538000-xx-y	600 V	60–480 V	datasheet	2–11
Solis (Ginlong) S6-EH1P10K-H-US	600 V	80–520 V	datasheet	3–11
Solis (Ginlong) Solis-1P7.6K-4G-US	600 V	100–500 V	datasheet	3–11
Qcells Q.VOLT H7.6SX	498 V	234–498 V	CEC test window	7–9

Microinverters (one per panel)

Microinverter	Recommended module power	Max DC input	MPPT	Voc cold / Vmp hot	Check	DC/AC
Enphase IQ8X-80-M-US	320–540 W	79.5 V	43–60 V	52.7 / 34 V	✗ Not a match: module voltage below MPPT range	1.18
APsystems (Alt Power System) DS3-L	265–570 W	60 V	28–45 V	52.7 / 34 V	✓ Within range	0.58
Enphase IQ8M-72-2-US	260–460 W	60 V	30–45 V	52.7 / 34 V	✓ Within range	1.38
Enphase IQ8A-72-2-US	295–500 W	60 V	32–45 V	52.7 / 34 V	✓ Within range	1.29

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

PanelsCity for chartSystem size

City	kWh / kW / yr	kWh / panel / yr	kWh / system / yr	Sun, kWh/m²/day
Los Angeles	1,676	754	12,067	6.08
Palmdale	1,835	826	13,212	6.69
Chula Vista	1,696	763	12,211	6.11
Huntington Beach	1,643	739	11,830	5.89
Riverside	1,696	763	12,211	6.21
Santa Clarita	1,724	776	12,413	6.28

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 450 W panels

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

Panel	Pmax	Efficiency	γ Pmax (CEC)	Voc, V	Isc, A	PVEL (product / brand)	SoCal permits (series)
JA Solar JAM72S20-450/MR	450 W	≈20.7%	−0.335	49.7	11.36	brand 11×	—
Qcells Q.TRON BLK M-G2+ 445	445 W	≈22.8%	−0.276	40.16	13.98	brand 11× (2016–2026)	40
Hyundai Energy Solutions HiN-T450NF(BK)	450 W	≈23.2%	−0.298	39.2	14.53	brand 5× (2017–2025)	37
REC Group REC450AA Pure-RX	450 W	≈22.3%	−0.248	65.1	8.81	brand 9× (2016–2025)	33

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 JA Solar

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

ManufacturerJA Solar
Listed in CEC asJA Solar
PVEL Top Performer (manufacturer)11 Scorecards (2014–2026)
RETC PV Module Index2023, 2024, 2025, 2026
Current panel series in CEC list22

Other series by SoCal permits

JAM54S31-xxx/MR · 152JAM54D41-xxx/MB · 17JAM72D30-xxx/MB · 3JAM54S30-xxx/MR · 1JAM66D45-xxx/LBJAM54D30-xxx/MB

Questions & answers

How efficient is the JA Solar JAM72S20-450/MR?

Calculated from the panel area (2.17 m²): about 20.7% for the 450 W class. 450 W over 2.17 m² equals about 207 W per square meter.

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

PVWatts v8 with typical-year weather gives about 754 kWh per year per 450 W panel in Los Angeles and about 826 kWh in Palmdale (20° roof, facing south, 14% system losses).

How much power does it lose on a hot roof?

With γ = −0.335 %/°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 = 52.7 V, Vmp at 74 °C cell = 34 V). Final design must follow the inverter manual and NEC 690.7.

Does it work with APsystems (Alt Power System) DS3-L microinverters?

Voltage check against the APsystems (Alt Power System) datasheet: Voc when cold 52.7 V vs max input 60 V; Vmp when hot 34 V vs MPPT low 28 V; recommended module power 265–570 W. Confirm on the microinverter maker’s compatibility list.

Has this panel been reliability-tested?

This exact series is not in published PVEL Top Performer tables; JA Solar was named a Top Performer in 11 Scorecards (2014–2026). RETC named JA Solar Overall Highest Achiever in 2023, 2024, 2025, 2026.

Sources

California Energy Commission — Solar Equipment Lists, PV Module List, Inverter List (snapshot Oct 7, 2026).
Qcells — manufacturer datasheet “Q.TRON BLK M-G2+ SERIES 415–440 Wp”.
Hyundai Energy Solutions — datasheet [US] NF(BK)(HiN) Series (N TOPCon Bifacial) 435~445W.
Kiwa PVEL — PV Module Reliability Scorecard, Top Performer lists 2014–2026.
RETC — PV Module Index reports 2023–2026.
NLR (formerly NREL) — System Advisor Model CEC inverter library (version 2026.7.3).
NLR (formerly NREL) — PVWatts v8, NSRDB PSM v3 typical-year weather for Los Angeles, Palmdale, Chula Vista, Huntington Beach, Riverside, Santa Clarita.
Inverter datasheets — APsystems (Alt Power System), Enphase, Solis (Ginlong), Tesla (manufacturer documents).
Building permits — Southern California permit portals. Equipment matched from permit descriptions.
Cali-Graf calculations — formulas and inputs are shown next to each calculated value (efficiency from area, temperature-corrected voltages, string sizing, energy estimates).