Illustration · 120 half-cut cells

Solar panelZhejiang Sunpro Power Technology

Zhejiang Sunpro Power Technology SPDG595-120M12

Name: Zhejiang Sunpro Power Technology SPDG595-120M12
Brand: Zhejiang Sunpro Power Technology

120 half-cut cells. Power classes 580–615 W in the CEC list.

CEC listed · Sep 11, 2024UL 61730

Power class

Power (STC)595 WCEC nameplate
Efficiency≈21.6%calculated from area
%/°C Pmax−0.351CEC listing test
PTC / STC93.8%PTC 558 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
SPDG580-120M12	580 W	40.70	18.32	33.60	17.27	≈21.0%	544 W	Sep 11, 2024
SPDG585-120M12	585 W	40.90	18.37	33.80	17.31	≈21.2%	549 W	Sep 11, 2024
SPDG590-120M12	590 W	41.10	18.42	34.00	17.35	≈21.4%	553 W	Sep 11, 2024
SPDG595-120M12	595 W	41.30	18.47	34.20	17.40	≈21.6%	558 W	Sep 11, 2024
SPDG600-120M12	600 W	41.50	18.52	34.40	17.45	≈21.7%	563 W	Sep 11, 2024
SPDG605-120M12	605 W	41.70	18.57	34.60	17.49	≈21.9%	568 W	Sep 11, 2024
SPDG610-120M12	610 W	41.90	18.62	34.80	17.53	≈22.1%	573 W	Sep 11, 2024
SPDG615-120M12	615 W	42.10	18.67	35.01	17.57	≈22.3%	578 W	Sep 11, 2024

≈ efficiency = Pmax ÷ CEC-listed area 2.76 m².

Build & dimensions

CEC PV Module List (Oct 7, 2026)

Module area2.76 m² (29.7 ft²)CEC-listed area
Cells120 half-cut cells
Back coverGlass (dual-glass module)

Heat & cold behaviour

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

	CEC listing test
Pmax coefficient γ	−0.351 %/°C
Voc coefficient β	−0.271 %/°C
Isc coefficient α	+0.053 %/°C
Operating cell temperature	NOCT 43.8 °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
580 W	428.2 W	30.88 V × 13.87 A	111.9 W	96%
585 W	431.7 W	31.07 V × 13.9 A	112.8 W	96%
590 W	435.3 W	31.25 V × 13.93 A	113.7 W	96%
595 W	439.1 W	31.43 V × 13.97 A	114.7 W	96%
600 W	442.9 W	31.62 V × 14.01 A	115.7 W	96%
605 W	446.5 W	31.8 V × 14.04 A	116.7 W	96%
610 W	450.2 W	31.98 V × 14.07 A	117.6 W	96%
615 W	453.9 W	32.18 V × 14.11 A	118.6 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

43.9 V

Voc when cold

per panel

27.4 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	3–13
Solis (Ginlong) S6-EH1P10K-H-US	600 V	80–520 V	datasheet	3–13
Solis (Ginlong) Solis-1P7.6K-4G-US	600 V	100–500 V	datasheet	4–13
Qcells Q.VOLT H7.6SX	498 V	234–498 V	CEC test window	9–11

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	997	11,967	6.08
Palmdale	1,835	1,092	13,102	6.69
Chula Vista	1,696	1,009	12,109	6.11
Huntington Beach	1,643	978	11,731	5.89
Riverside	1,696	1,009	12,109	6.21
Santa Clarita	1,724	1,026	12,309	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 595 W panels

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

Panel	Pmax	Efficiency	γ Pmax (CEC)	Voc, V	Isc, A	PVEL (product / brand)	SoCal permits (series)
Zhejiang Sunpro Power Technology SPDG595-120M12	595 W	≈21.6%	−0.351	41.3	18.47	—	—
Phono Solar PS595M8GFH-24/TNH	595 W	≈23.2%	−0.293	53.2	13.84	product 2024, 2025	1
Qcells Q.PEAK DUO XL-G11S.3/BFG 595	595 W	≈21.9%	−0.348	53.63	13.77	product 2024, 2025, 2026	1
VSUN (Vietnam Sunergy) VSUN595N-144MH	595 W	≈23.1%	−0.309	52.69	13.98	brand 6× (2021–2026)	1

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 Zhejiang Sunpro Power Technology SPDG595-120M12?

Calculated from the panel area (2.76 m²): about 21.6% for the 595 W class. 595 W over 2.76 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 997 kWh per year per 595 W panel in Los Angeles and about 1,092 kWh in Palmdale (20° roof, facing south, 14% system losses).

How much power does it lose on a hot roof?

With γ = −0.351 %/°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 3–13 panels per string (Voc at 2 °C = 43.9 V, Vmp at 74 °C cell = 27.4 V). Final design must follow the inverter manual and NEC 690.7.

Sources

California Energy Commission — Solar Equipment Lists, PV Module List, Inverter List (snapshot Oct 7, 2026).
Kiwa PVEL — PV Module Reliability Scorecard, Top Performer lists.
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 — 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).