Overview
The Fortress Power Envy 10kW is an all-in-one hybrid inverter combining a solar inverter, 210A battery charger, and transfer switch in an IP65 enclosure. It provides 10,000W of continuous split-phase 120/240Vac output for grid-tied or off-grid homes, and it is the higher-output option over the 8kW model.
Planning a system? Read our guide: How to size a battery backup system for your home.
From the manufacturer
About The Fortress Power Envy 10kW Hybrid Inverter The Fortress Power Envy 10kW is an all-in-one hybrid inverter that combines a solar inverter, 210A battery charger, and transfer switch into a single IP65-rated enclosure. It delivers 10,000W of continuous split-phase 120/240Vac output and supports both grid-tied and off-grid operation, making it the higher-output option in the Fortress Power Envy 8/10K line. The Envy 10kW is sized for whole-home backup, larger residential systems, and light commercial installations where the 8kW model may not provide enough headroom for demanding loads like central air conditioning, EV charging, or shop equipment. Solar Input The Envy 10kW has two independent MPPT channels with two string inputs each (four total PV inputs). Each MPPT accepts up to 6,000W, for a combined maximum PV input of 15,000W. The DC input voltage range spans 100-600Vdc (550V max recommended), with a nominal input voltage of 360Vdc and a full power MPPT operating range of 210-500Vdc. Maximum usable input current is 25A per MPPT, with a short circuit rating of 31A per MPPT. Of the 15kW solar capacity, up to 12kW can be delivered simultaneously to the battery bank and AC outputs. This means the Envy 10kW can charge batteries and power household loads from solar at the same time without throttling either function during peak production hours. Grid and Generator Integration The Envy 10kW features a 14,400W AC passthrough at 240V for grid power. When the grid is available, the inverter can pass power directly to household loads while simultaneously charging the battery bank. A dedicated auto-start generator port rated at 50A / 12kW allows a backup generator to charge batteries and run loads when both solar and grid are unavailable. Built-in 63A AC breakers cover grid input, load output, and the generator connection, while a 250A DC breaker protects the battery circuit. The inverter manages the transition between grid, generator, solar, and battery power automatically, with a switching time of less than 20ms. For grid-tied systems, the Envy 10kW can export up to 10,000W back to the utility at 240V. It supports net metering, time-of-use optimization, peak shaving, and zero-export modes. The inverter is VPP (Virtual Power Plant) compatible and approved by utilities across the U.S. and Puerto Rico, which means homeowners can participate in demand response programs and receive compensation for discharging stored energy during peak grid demand. Battery Compatibility The Envy 10kW operates on a 48Vdc nominal battery bus with a voltage range of 40-60Vdc. It supports a maximum charge and discharge current of 210A and a maximum charge/discharge power of 10,000W. The inverter communicates with battery management systems through closed-loop protocols for real-time monitoring of voltage, current, temperature, and SOC (State of Charge). Fortress Power designed the Envy to pair directly with their own battery lineup, including the eVault MAX 18.5kWh, eFlex 5.4kWh, eFlex MAX 5.4kWh, eForce, eBoost, and LFP-10 MAX systems. Other lithium batteries can be connected in open-loop mode, and lead-acid batteries are also supported. Scalability A single Envy 10kW covers most whole-home backup scenarios, but the inverter supports parallel operation of up to 10 units for a combined output of 100kW. Two or more units can also be configured for commercial three-phase 120/208V or 208V output, making the Envy a flexible platform for mixed-use residential and light commercial projects. Built-In Safety and Code Compliance The Envy 10kW comes with a built-in APsmart Module Level Rapid Shutdown (RSD) transmitter and button, meeting NEC 690.12 requirements without additional external hardware. It is also compatible with Tigo transmitters for installations that use Tigo optimizers. The integrated 63A AC breakers and 250A DC battery breaker are built into the enclosure, reducing the number of external disconnect components and cutting down installation time. Moni
Warranty terms mentioned in this description are the manufacturer’s. Our own coverage is the 30-day limited warranty.