The Fortress Power Envy True 12kW is a 48V hybrid inverter built for whole-home backup, solar + storage integration, and off-grid systems, with 12kW of continuous output on 120/240V split-phase power.
The Envy True 12kW is a hybrid inverter architecture — it operates grid-tied with battery backup, and also functions in off-grid configurations. It is not a simple grid-tie-only unit and it is not a chargeverter (AC-to-DC charger only). Note: If you would like to review the manufacturer Product Specifications, Warranty, Brochure, etc., for this system, please refer to the "Resources (System Manuals and Warranty)" Tab above on this page.
Critical Power & Interconnection Requirements
- AC output voltage/phase: 120/240V split-phase (three-phase 208V applications require two or more units in parallel — per manufacturer data for the related Duo 21 platform; confirm three-phase support specifics for ENVYTRUE12 configuration before ordering [NEEDS VERIFICATION]).
- Battery DC input: 48V nominal. NOT compatible with 12V or 24V battery banks.
- Continuous AC output: 12 kW.
- Max PV input capacity: 21,000 W (21 kW).
- AC passthrough: 200A, for uninterrupted power to critical loads and full-home circuits during grid outages.
- Parallel/stacking: Up to 10 units, for a maximum combined output of 120 kW AC.
- Does NOT function as a standalone battery charger (Chargeverter) — it is a full hybrid inverter/charger architecture.
- Grid export/zero-export and VPP participation depend on utility program enrollment and are NOT automatically enabled on installation.
On split-phase retrofits, techs commonly run into neutral-ground bonding conflicts when the Envy True 12kW is installed downstream of an existing main panel that already carries a bonded neutral — this creates parallel neutral paths and nuisance ground-fault trips. Verify bonding location before final torque-down of lugs; a floating neutral at the inverter (bonded only at the service entrance) prevents circulating currents and intermittent GFCI-type fault codes down the road. Confirm continuity and isolation with a digital multimeter set to continuity/low-resistance mode before energizing the backup loads panel. This isolation check, combined with proper labeling of the integrated rapid shutdown transmitter conductors, is what gets you through inspection under NEC 690 (PV systems) and NEC 706 (energy storage systems) on the first pass.
Key Benefits
- 21 kW max PV input supports large residential solar arrays without needing a second charge controller.
- 200A AC passthrough keeps full-home circuits powered during grid outages, not just designated critical loads.
- Integrated AC/DC breakers and a built-in rapid shutdown transmitter reduce the number of external components needed for a code-compliant install.
- Parallel scalability to 120 kW AC lets you size a system for future load growth without a full inverter swap.
- Remote monitoring and firmware updates via the Fortress Power mobile app support ongoing system diagnostics without a truck roll.
- Compatible with zero-export and load-shifting modes for buyers optimizing time-of-use rate schedules.
| Spec | Value | Unit |
|---|---|---|
| Continuous AC Output | 12 | kW |
| AC Output Voltage | 120/240 | V split-phase |
| DC Battery Voltage | 48 | V |
| Max PV Input | 21000 | W |
| AC Passthrough Rating | 200 | A |
| Max Parallel Units | 10 | units |
| Max Parallel Output | 120 | kW AC |
Note: See "Resources (System Manuals and Warranty)" Tab above for full specifications.
Compatibility & Fitment
- Compatible with Fortress Power 48V battery systems, including eForce, eVault MAX, and eFlex MAX.
- Supports LiFePO4 (LFP) battery chemistry via the listed Fortress Power battery lines.
- Suited to residential and light commercial applications requiring split-phase 120/240V service.
- NOT compatible with 12V or 24V battery banks.
- NOT a standalone Chargeverter — it is a full hybrid inverter/charger, not an AC-to-DC-only charging device.
- Three-phase 208V operation requires a minimum of two or more units in parallel; a single unit does not support three-phase on its own [NEEDS VERIFICATION for ENVYTRUE12 specifically, as this detail was sourced from the related Duo 21 spec sheet].
- Wi-Fi module inclusion status not confirmed in manufacturer data provided [NEEDS VERIFICATION].
Compliance & Environment
| Category | Detail |
|---|---|
| Rapid Shutdown | Integrated rapid shutdown transmitter; supports NEC 2017 & 2020 code compliance |
| NEC Article Applications | NEC 690 (PV Systems), NEC 706 (Energy Storage Systems) — referenced via rapid shutdown code compliance claims |
| UL Listings | [NEEDS VERIFICATION] — not specified in manufacturer data provided |
| NEMA Enclosure Rating | [NEEDS VERIFICATION] — not specified in manufacturer data provided |
| Utility Approval | Approved by utilities across the U.S. and Puerto Rico per manufacturer claim; verify specific state/utility approval before purchase |
FAQ
Can this inverter sell power back to the grid?
The Envy True 12kW supports net metering, time-of-use programs, and Virtual Power Plant (VPP) participation in approved utility territories, allowing grid export where utility programs allow it. Zero-export operation is also supported for installations that require it. Confirm your local utility's interconnection agreement before enabling export.
What battery voltage is required?
This inverter requires a 48V DC battery bank. It is designed for use with Fortress Power 48V batteries, including the eForce, eVault MAX, and eFlex MAX. It is NOT compatible with 12V, 24V, or other DC battery bank voltages.
Can I parallel multiple units together?
Yes. Up to 10 Envy True 12kW units can be paralleled for a combined output of up to 120kW AC. Three-phase configurations require a minimum of two or more inverters in parallel.
Is this UL 1741 listed for utility interconnection?
The manufacturer data provided does not list a specific UL 1741 certification number for the Envy True 12kW. [NEEDS VERIFICATION] Confirm current certification status against the manufacturer's official documentation before relying on it for utility interconnection approval.
Does this unit include Wi-Fi monitoring out of the box?
The unit includes a Wi-Fi antenna port for Guardian monitoring and supports remote firmware updates through the Fortress Power mobile app. Whether a Wi-Fi module ships standard or as an add-on is not specified in the manufacturer data provided. [NEEDS VERIFICATION]
Warranty & Registration
Manufacturer warranty terms for the Envy True 12kW are not itemized in the data provided (duration, closed-loop vs. open-loop battery communication warranty stipulations, and registration process). [NEEDS VERIFICATION] Refer to the "Resources (System Manuals and Warranty)" Tab above on this page for the manufacturer's official warranty document before purchase.
