Fortress Power Envy Duo 21-G

The Fortress Power Envy Duo 21-G pairs the Envy Duo 21 hybrid inverter with a Guardian gateway for cloud-connected monitoring and VPP/EnergyBroker eligibility. The Envy Duo 21 is a 48V hybrid inverter built for demanding residential and light commercial energy needs, accepting up to 25kW of PV input across 3 MPPTs and supporting both 240V split-phase and 208V three-phase configurations. It delivers 12kW of continuous backup output power in either configuration, with max export power of 16kW, and is compatible with Fortress Power's 48V battery lineup (eForce, eBoost, eFlex, eFlex MAX, eVault MAX). Up to 10 units can be paralleled for a total output of 120kW.

The included Guardian gateway connects the system to the cloud for real-time monitoring of state of charge, voltage, current, and battery temperature down to the individual battery level. Guardian is required for participation in Fortress Power's VPP and EnergyBroker programs, and enables remote firmware updates, live technical support chat, and secure data sharing with Fortress engineers through the Owner and Pro mobile apps.

Installation should be performed by a licensed and certified installer.

Datasheets and manuals:

• Envy Duo 21 Data Sheet (English)
• Envy Duo 21 Installation Manual (English)
• Envy Duo 21 Warranty (English)
• Guardian (Box) Data Sheet
• Guardian (Box) Installation Manual
• Guardian (Box) Warranty

Pricing: (add once confirmed)

Specifications — Envy Duo 21 Inverter:

• Max PV input: 25,000W (25kW), 3 MPPTs
• Continuous output power: 12,000VA @ 240V / 12,000VA @ 208V
• Max export power: 16,000W @ 240V / 13,800W @ 208V
• Nominal battery voltage: 48V (40-60V range)
• Max charge/discharge current: 250A
• Paralleling: up to 10 units (120kW total)
• Max CEC efficiency: 96.9%
• Dimensions: 22.3 x 35.2 x 11.2 in (566 x 893 x 285 mm)
• Weight: 125.71 lbs (57 kg)
• Enclosure rating: NEMA4X / IP66
• Communication: RS485 / Wi-Fi / CAN
• Operating temp range: -25°C to 60°C (derating above 40°C)

Specifications — Guardian Gateway:

• Power consumption: 5W, 24V @ 1A power supply
• Communication: 1x MODBUS/TCP, 2x MODBUS/RTU, 2x CAN 2.0
• Operation frequency: 2.4GHz
• Weight: 0.8 lbs (0.4 kg)
• Dimensions: 7.25" x 6" x 1.25"
• Housing: IP23
• Mounting: DIN rail mount