Illustration · 132 half-cut cells

Solar panelSunplus Optimum

Sunplus Optimum SR5-66HBD-655M

Name: Sunplus Optimum SR5-66HBD-655M
Brand: Sunplus Optimum

132 half-cut cells, bifacial. Power classes 635–675 W in the CEC list.

CEC listed · Aug 11, 2023UL 61730Bifacial

Power class

Power (STC)655 WCEC nameplate
Efficiency≈21.6%calculated from area
%/°C Pmax−0.386CEC listing test
PTC / STC92.8%PTC 608 W (CEC)

Power classes

CEC PV Module List (Oct 7, 2026) · Cali-Graf calculation · 8 models

Model	Pmax	Voc, V	Isc, A	Vmp, V	Imp, A	Efficiency	PTC	CEC listed
SR5-66HBD-635M	635 W	44.90	18.17	37.10	17.13	≈21.0%	589 W	Aug 11, 2023
SR5-66HBD-640M	640 W	45.10	18.22	37.30	17.17	≈21.1%	594 W	Aug 11, 2023
SR5-66HBD-645M	645 W	45.30	18.27	37.50	17.21	≈21.3%	598 W	Aug 11, 2023
SR5-66HBD-655M	655 W	45.70	18.37	37.90	17.30	≈21.6%	608 W	Aug 11, 2023
SR5-66HBD-660M	660 W	45.90	18.42	38.10	17.34	≈21.8%	613 W	Aug 11, 2023
SR5-66HBD-665M	665 W	46.10	18.47	38.30	17.38	≈21.9%	618 W	Aug 11, 2023
SR5-66HBD-670M	670 W	46.30	18.52	38.50	17.42	≈22.1%	622 W	Aug 11, 2023
SR5-66HBD-675M	675 W	46.50	18.57	38.70	17.46	≈22.3%	627 W	Aug 11, 2023

≈ efficiency = Pmax ÷ CEC-listed area 3.03 m².

Heat & cold behaviour

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

	CEC listing test
Pmax coefficient γ	−0.386 %/°C
Voc coefficient β	−0.291 %/°C
Isc coefficient α	+0.050 %/°C
Operating cell temperature	NOCT 44.8 °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
635 W	470.6 W	34.2 V × 13.76 A	122.6 W	97%
640 W	474.4 W	34.4 V × 13.79 A	123.7 W	97%
645 W	478.2 W	34.6 V × 13.82 A	124.3 W	96%
655 W	485.1 W	34.9 V × 13.9 A	126.4 W	96%
660 W	488.9 W	35.1 V × 13.93 A	127.4 W	97%
665 W	492.8 W	35.3 V × 13.96 A	128.4 W	97%
670 W	496.6 W	35.5 V × 13.99 A	129.5 W	97%
675 W	500.9 W	35.7 V × 14.03 A	130.2 W	96%

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)

CityColdest air, °CHottest cell, °CString inverter

48.8 V

Voc when cold

per panel

29.8 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	3–12
Solis (Ginlong) S6-EH1P10K-H-US	600 V	80–520 V	datasheet	3–12
Solis (Ginlong) Solis-1P7.6K-4G-US	600 V	100–500 V	datasheet	4–12
Qcells Q.VOLT H7.6SX	498 V	234–498 V	CEC test window	8–10

Microinverters (one per panel)

No microinverter in the reference set lists this power class in its recommended module power range.

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	1,098	12,076	6.08
Palmdale	1,835	1,202	13,221	6.69
Chula Vista	1,696	1,111	12,220	6.11
Huntington Beach	1,643	1,076	11,838	5.89
Riverside	1,696	1,111	12,220	6.21
Santa Clarita	1,724	1,129	12,421	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 655 W panels

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

Panel	Pmax	Efficiency	γ Pmax (CEC)	Voc, V	Isc, A	PVEL (product / brand)
Sunplus Optimum SR5-66HBD-655M	655 W	≈21.6%	−0.386	45.7	18.37	—
Canadian Solar CS7N-655MB-AG	655 W	≈21.3%	−0.390	45.2	18.43	product 2024
Hyundai Energy Solutions HiN-T650NJ	650 W	≈23.5%	−0.273	56.7	14.51	brand 5× (2017–2025)
JinkoSolar JKM650N-66HL4M-BDV	650 W	≈24.1%	−0.299	50.28	16.44	product 2025

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 Sunplus Optimum SR5-66HBD-655M?

Calculated from the panel area (3.03 m²): about 21.6% for the 655 W class. 655 W over 3.03 m² equals about 216 W per square meter.

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

PVWatts v8 with typical-year weather gives about 1,098 kWh per year per 655 W panel in Los Angeles and about 1,202 kWh in Palmdale (20° roof, facing south, 14% system losses).

How much power does it lose on a hot roof?

With γ = −0.386 %/°C, at a 77 °C cell temperature (hottest modeled hour in Palmdale) output is about 20% 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 3–12 panels per string (Voc at 2 °C = 48.8 V, Vmp at 74 °C cell = 29.8 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.

Sources

California Energy Commission — Solar Equipment Lists, PV Module List, Inverter List (snapshot Oct 7, 2026).
Hyundai Energy Solutions — datasheet [US] NJ(HiN) Series (N TOPCon Bifacial) 640~645W.
JinkoSolar — datasheet THE MOST DEPENDABLE SOLAR PRODUCT.
Kiwa PVEL — PV Module Reliability Scorecard, Top Performer lists.
NLR (formerly NREL) — System Advisor Model CEC module and inverter libraries (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 — Solis (Ginlong), Tesla (manufacturer documents).
Cali-Graf calculations — formulas and inputs are shown next to each calculated value (efficiency from area, temperature-corrected voltages, string sizing, energy estimates).