Sol-Ark 18K-2P 48V Hybrid Inverter, 18kW Battery Output, 28.8kW Solar Input, IP65 All-in-One Inverter, UL 1741

Overview

Combining an 18kW inverter, three MPPT solar charge controllers, a battery charger, an automatic transfer switch, and a grid interface, the Sol-Ark 18K-2P sits in a single outdoor-rated IP65 enclosure. Its 200A grid pass-through can back up an entire main panel without a critical loads subpanel.

Planning a system? Read our guide: How to size a battery backup system for your home.

Key benefits

• 36kW surge for 10 seconds starts central air, well pumps, and heavy motor loads without a soft start.
• 5ms transfer keeps computers and networking equipment running through an outage.
• Three independent MPPTs track arrays on different roof faces separately.
• Battery agnostic, working with lithium through closed-loop BMS communication or with lead-acid.

Key features

• 18kWAC continuous at 120/240V split-phase
• 28.8kW DC-coupled solar input across six PV inputs, plus up to 19.2kW of AC-coupled solar
• Each MPPT runs 150 to 425V with 36A maximum usable current
• Charges and discharges 48V banks at up to 350A, with a 200Ah minimum bank
• Grid-tied, zero export, time-of-use, and off-grid modes set by LCD or the MySolArk app
• Rapid shutdown capability for NEC compliance, UL 1741

Ideal use

Built for whole-home backup where the inverter sits between the utility meter and the main panel, or for large off-grid homes.

Key specifications

Model / SKU

18K-2P

Brand

Sol-Ark

Category

Whole-home backup

Voltage

48V

Rated power

18,000 W

From the manufacturer

About the Sol-Ark 18K-2P Hybrid Inverter The Sol-Ark 18K-2P is an all-in-one hybrid inverter that combines an 18kW inverter, three MPPT solar charge controllers, a battery charger, automatic transfer switch, and grid interface in a single outdoor-rated enclosure. It outputs 18kWAC continuous at 120/240V split-phase with a 36kW surge capacity for 10 seconds, which is enough to start central air conditioners, well pumps, and other heavy motor loads without a soft start. The 200A grid pass-through means you can back up your entire main panel without building a critical loads subpanel, and a 5ms transfer time keeps electronics running through the switch. Solar Input The 18K-2P has three independent MPPT channels with two string inputs each (six total PV inputs). Each MPPT operates across a 150 to 425V range with a maximum usable current of 36A and a short circuit rating of 54A. Combined DC-coupled solar input is 28.8kW. For systems that need more PV, the inverter also supports up to 19.2kW of AC-coupled solar from a separate grid-tied inverter, bringing total possible solar input over 40kW. The three independent MPPTs allow arrays on different roof faces or orientations to be tracked separately without production losses from mismatched strings. Battery Integration The inverter charges and discharges 48V battery banks at up to 350A. It requires an absolute minimum battery bank of 200Ah. CAN and RS485 communication (RJ45 connectors) support closed-loop BMS integration with most major lithium battery brands including Pytes, Renon, and others. The inverter is battery agnostic and also works with lead-acid banks for budget-conscious installations, though lithium is recommended for systems at this power level. Operating Modes The 18K-2P supports multiple operating modes that can be configured through the onboard LCD or the MySolArk monitoring app. Grid-tied mode sells excess solar production back to the utility. Zero export mode uses solar and battery without sending power to the grid. Time-of-use mode charges batteries during off-peak hours and discharges during peak rate periods. Off-grid mode operates entirely independent of the grid. Smart load outputs let you prioritize specific circuits based on battery SOC and available solar. These modes are programmable by season and time of day. Grid Pass-Through and Transfer The 200A pass-through rating is one of the defining features of this inverter. Most residential hybrid inverters require a critical loads subpanel because they can only pass 30 to 50A. The 18K-2P passes 200A, which means it can sit between the utility meter and your main panel and back up the entire house without rewiring. When grid power fails, the inverter transfers to battery in approximately 5ms, fast enough that computers, networking equipment, and most sensitive electronics continue running without interruption. Rapid Shutdown and Safety The 18K-2P includes RSD (Rapid Shutdown) capability for NEC compliance. Wire an external RSD button like the IMO RSD Initiator to the inverter, and when activated, the 18K shuts down and sends a shutdown signal to any connected RSD transmitters and devices on the array. The inverter also includes integrated AFCI (Arc Fault Circuit Interrupter) and GFDI (Ground Fault Detector/Interrupter) protection. Sol-Ark designs the 18K firmware in the US, and all monitoring data is processed domestically. Enclosure and Installation The IP65 / NEMA 3R enclosure is rated for outdoor installation in temperatures from -40°F to 140°F (-40°C to 60°C). At 137 lbs and 34 x 18 x 11 inches, it mounts on an exterior wall adjacent to the main panel or battery enclosure. The all-in-one design means no external fuses, breakers, or combiner boxes are required for the inverter itself. A dedicated generator input with auto-start functionality is built in for systems that need generator backup in addition to solar and battery. Scalability Up to 12 Sol-Ark 18K-2P units can be paralleled for larger installations,

Warranty terms mentioned in this description are the manufacturer’s. Our own coverage is the 30-day limited warranty.

Before you order

We confirm compatibility, installation requirements, and delivery details with you during order review, before any payment. Home electrical work may require a qualified installer.

Ask our team to help size batteries and PV strings for the Sol-Ark 18K-2P in your home. Message our team on WhatsApp.