Illustration

Hybrid inverterSol-Ark

Sol-Ark Limitless 18K-2P-LV

Name: Sol-Ark Limitless 18K-2P-LV
Brand: Sol-Ark

Hybrid inverter, dc-coupled hybrid (pv + battery). 2 models, 18 kW AC at 208 V / 240 V.

UL 1741 SBCEC listed · Aug 21, 2025

Model

Rated AC power18 kW
CEC weighted efficiency97.0%

Models & power ratings

CEC Grid Support Inverter List (Oct 7, 2026) · NLR SAM inverter library · 2 models

Model	Nominal AC	Grid voltage	CEC continuous	Rated AC (SAM)	CEC weighted eff.	DC test window	CEC listed	UL 1741 SB
Limitless 18K-2P-LV	18 kW	208 V	15.6 kW	15.6 kW	97.0%	250–425 V	Aug 21, 2025	SB
Limitless 18K-2P-LV	18 kW	240 V	17.9 kW	17.9 kW	97.0%	250–425 V	Aug 21, 2025	SB

Some models are also on the CEC Battery Inverter list — one product, two listings.

DC input (PV side)

CEC Grid Support Inverter List (Oct 7, 2026) · NLR SAM inverter library

CEC test DC voltages (min / nom / max)250 / 338 / 425 V
DC input at rated output (CEC test)18.5 kW

Efficiency

CEC Grid Support Inverter List (Oct 7, 2026) · NLR SAM inverter library

CEC weighted efficiency97.0%
Night-time standby (tare)1.37 W
Power to start converting95.2 W

CEC weighted efficiency is measured by an accredited lab at six power levels and three DC voltages — the number to compare between inverters.

Grid & smart-inverter certification

CEC Grid Support Inverter List (Oct 7, 2026)

UL 1741 SB (3rd ed.)Yes — TUV Rheinland of North America, certificate May 8, 2025
UL 1741 SA (SA8–SA13)No
Volt-VAr with reactive power priority (SA13)No
Freq-Watt / Volt-Watt (SA14–15)No
Disable permit service / limit active power (SA17–18)No
CSIP (IEEE 2030.5) conformanceVia gateway during testing (Y*)
Monitor key data & scheduling (Rule 21 Phase 3)No
Power control system (PCS)Stated in CEC listing (power control system)
CEC listedAug 21, 2025
Last CEC updateNov 3, 2025

UL 1741 SB is required for new interconnections in California (Rule 21) since 2026.

Panel compatibility & string sizing

NLR SAM inverter library · NLR PVWatts v8 · CEC PV Module List · Cali-Graf calculation

CityColdest air, °CHottest cell, °C

Limitless 18K-2P-LV: max DC 425 V · MPPT 250–425 V (CEC test window)

Most-permitted panels in Southern California

Panel	Power	Voc cold	Vmp hot	Panels per string	Installed together
Qcells Q.PEAK DUO BLK ML-G10.C+ 410	410 W	48.1 V	30.6 V	no fit	—
Qcells Q.PEAK DUO BLK ML-G10+ 410	410 W	48.1 V	30.6 V	no fit	—
LONGi LR5-54HABB-400M	400 W	39.3 V	25.3 V	10–10	—
JA Solar JAM54S31-405/MR	405 W	39.4 V	25.5 V	10–10	—
Hyundai Solutions HiN-T440NF(BK)	440 W	40.9 V	27 V	10–10	—
Silfab Solar SIL-440QD	440 W	41.1 V	28 V	9–10	—
Qcells Q.TRON BLK M-G2+ 430	430 W	41.3 V	28 V	9–10	—
Qcells Q.TRON BLK M-G2.H+ 430	430 W	41.3 V	28 V	9–10	—
REC Group REC460AA Pure-RX	460 W	68.8 V	47.1 V	6–6	—
Elin (Sirius PV) ELNSM54M-HC-410	410 W	39.3 V	25.3 V	10–10	—
Qcells Q.TRON BLK M-G2.C+ 430	430 W	41.3 V	28 V	9–10	—
Tesla TSP-420	420 W	43.4 V	27.7 V	no fit	—

Voltage check only, from CEC panel data and NLR weather for the city. Final design must follow the inverter manual and NEC 690.7.

Compare with similar 18 kW inverters

CEC Grid Support Inverter List (Oct 7, 2026) · building permits

Inverter	Power	CEC weighted eff.	DC test window	UL 1741 SB	Latest CEC	SoCal permits
Sol-Ark Limitless 18K-2P-LV	18 kW–18 kW	97.0%	250–425 V	Yes	2025	0
Shenzhen Lux Power Technology LXP-LB-US xK	8 kW–16 kW	97.0%	210–480 V	Yes	2025	1
Suzhou Ample ESS AP-LxK-SPUS	7.98 kW–15 kW	96.5%	108–480 V	Yes	2026	—
Shenzhen Lux Power Technology GEN-HB-US 25K	21.6 kW–25 kW	96.5%	190–480 V	Yes	2026	—
SRNE Solar HEBP48150U320-H	15 kW–15 kW	96.5%	135–500 V	Yes	2026	—

Same type and grid voltage, power range covering this model; same fields from the same sources.

About Sol-Ark

CEC Grid Support Inverter List (Oct 7, 2026)

ManufacturerSol-Ark
Listed in CEC asSol-Ark
Websitesol-ark.com
Models on CEC lists45

Other series

12K-2P-LLLimitless xxK-LVxxK-3P-480VxxK-3P-208V5K-120V/8K-230V-1P

Documents

manufacturer documents

PDF
L3 Series Limitless Lithium 208V Datasheet
Datasheet · Sol-Ark · Aug 2026
PDF
L3 Series LimitLess Lithium 208V Datasheet
Datasheet · Sol-Ark · Nov 2025
PDF
L3 Series LimitLess Lithium 480V Datasheet
Datasheet · Sol-Ark · Nov 2025
PDF
Limitless 12K-2P-LL Hybrid Inverter Datasheet (EN)
Datasheet · Sol-Ark · Jul 2026
PDF
Limitless 12K-2P-LL Hybrid Inverter Installation Manual
Manual · Sol-Ark · Jul 2026
PDF
Limitless 12K-2P-LL Hybrid Inverter Quickstart Guide
Manual · Sol-Ark · Jul 2026

Questions & answers

How efficient is the Sol-Ark Limitless 18K-2P-LV?

The California Energy Commission lists a weighted efficiency of 97.0% for Sol-Ark Limitless 18K-2P-LV models, measured at six power levels and three DC voltages.

What sizes does the Sol-Ark Limitless 18K-2P-LV come in?

The CEC list includes 2 models from 18 kW to 18 kW AC: Limitless 18K-2P-LV, Limitless 18K-2P-LV.

Is the Sol-Ark Limitless 18K-2P-LV certified to UL 1741 SB?

Yes — the CEC Grid Support Inverter List shows UL 1741 SB for all models.

Can the Sol-Ark Limitless 18K-2P-LV be used with a battery?

The CEC lists it as a dc-coupled hybrid (pv + battery).

What is the Limitless 18K-2P-LV’s DC input voltage range?

CEC tested it at 250–425 V DC.

Sources

California Energy Commission — Grid Support Inverter List (solar and battery inverters), data as of Oct 7, 2026. Manufacturer-reported, confirmed by CEC against certificates and test reports.
Sol-Ark — document library on the manufacturer’s website (links above).
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, Riverside, Santa Clarita, Chula Vista, Huntington Beach.
California Energy Commission — PV Module List (module electrical data for the compatibility check).
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).