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Powerful enough to start a 5-ton AC unit, the EG4 FlexBOSS21 (V 1.1) is a 48V split-phase hybrid inverter/charger. It supports 21kW of PV input across three MPPTs.
Planning a system? Read our guide: How to size a battery backup system for your home.
For residential or commercial systems with large arrays and heavy motor loads.
Versatile and Powerful Hybrid Inverter The EG4 FlexBOSS21 (V 1.1) is a versatile 48V split-phase, hybrid inverter/charger that offers the same dependable power as the 18kPV with enhanced flexibility. Powerful enough to start a 5-ton AC unit, the FlexBOSS21 supports 21kW of PV input. Capable of paralleling up to 16 units together, the FlexBOSS21 has an impressive total output of 256kW continuous when using PV input. Three MPPTs give users optimal control over their solar needs, while the updated EG4 monitoring software allows for convenient total remote management, complete with mobile notifications and remote setting. Seamless interaction with GridBOSS gives users control over their entire Energy Storage System (ESS). EG4 FlexBOSS21 LCD Screen Kit sold separately Key Features: Flexible Power Options: Operate off-grid, with grid support, or sell excess power back to the grid. High PV Input Voltage: Supports up to 600V DC, allowing reduced cable sizes. Smart Connectivity: Remote access with Wi-Fi and closed-loop communication with compatible batteries. Safety-First Design: Includes rapid shutdown, ground fault monitoring, arc-fault protection, and robust safety certifications. UL 1741 Certificate of Compliance CEC Solar Equipment Listing Why Choose EG4 FlexBOSS21? The FlexBOSS21 combines efficiency, durability, and innovation, making it a top choice for those seeking robust energy solutions. Its advanced monitoring and safety features provide reliable power and peace of mind for residential or commercial installations. Elevate Your Energy Solutions Today: Explore the potential of the EG4 FlexBOSS21 Hybrid Inverter and enhance your energy management system. Whether it’s your first project or your fifth, our USA-based team is here for you. Lifetime support means you’re never on your own.
Warranty terms mentioned in this description are the manufacturer’s. Our own coverage is the 30-day limited warranty.
We confirm compatibility, installation requirements, and delivery details with you during order review, before any payment. Home electrical work may require a qualified installer.
Our team can help plan a FlexBOSS21 system around your array. Message our team on WhatsApp.
EG4
Off-grid systems cost less with the EG4 FlexBOSS21, which trades a larger transfer switch for more output than the 18kPV. It is an all-in-one 120/240V hybrid inverter for 48V banks with 12kW continuous output, rising to 16kW with solar.
$2,879.99
EG4
Designed for whole-home backup, the EG4 18kPV hybrid inverter works grid-tied, grid-assist, or fully off-grid. It delivers 12,000W of continuous output with up to 21,000W of recommended solar input.
$3,199.99
EG4
Installers and DIY builders get a 48V split-phase hybrid inverter in the EG4 FlexBOSS18. It offers 13kW continuous output with PV, 18kW of solar input, and 10kW battery-only output.
$2,559.99
EG4
With 18kW of solar input and up to 12kW of output, the EG4 18kPV hybrid inverter supplies more power than most homes need. It works for fully off-grid systems and grid-tied systems with sell-back.
$3,199.99