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Envy 12kW 1-Phase Energy Storage System – 4 eFlex 5.4 G2 Modules, DuraRack - Envy12KW4-DuraRack

Envy 12kW 1-Phase Energy Storage System – 4 eFlex 5.4 G2 Modules, DuraRack - Envy12KW4-DuraRack

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SKU: PES-SPS-SIV-0789MPN: Envy12KW4-DuraRackBrand: Fortress Power
Regular price $16,716.09 USD
Regular price Sale price $16,716.09 USD
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SKU
PES-SPS-SIV-0789
MPN
Envy12KW4-DuraRack
OEM Authorized Full Warranty 7-10 Business Days Delivery

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Fortress Power

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Fortress Envy12kW + (4) eFlex 5.4 kWh G2 + DuraRack Enclosure

SKU/MPN: Envy12KW 4-DuraRack • Application: Whole-home backup / grid-tied with storage • Chemistry: LiFePO4 (48 V)

What’s included

  • 1× Envy True 12 kW Hybrid Inverter — 200 A AC passthrough; up to 21 kW PV (3 MPPT); AC/DC coupling; generator input; NEMA 4X/IP65; 34.2 × 20.5 × 11.2 in; 127 lb.
  • 4× eFlex 5.4 kWh Batteries (G2) — 51.2 V, 105 Ah LFP; IP65; 18 × 23 × 7.3 in; 108 lb each.
  • 1× DuraRack Enclosure — outdoor-rated cabinet for up to four eFlex/eFlex MAX; integrated busbars and battery cables; 29.88 × 41.97 × 17.83 in; 153.2 lb.

Highlights

  • ~21.6 kWh usable storage (4 × 5.4 kWh) with modular expansion options on additional racks.
  • Hybrid flexibility: Works with new or existing PV via AC or DC coupling; fast transfer (<20 ms) for backup.
  • Closed-loop integration: CAN/RS-485 comms between Envy and Fortress batteries for optimized charging and warranty compliance.
  • Outdoor-ready hardware: Envy NEMA 4X/IP65; eFlex IP65; DuraRack IP65 (indoor/outdoor).

Key specs

Inverter Output 12 kW continuous; 120/240 V split-phase (10.4 kW @ 120/208 V); transfer < 20 ms
PV Input Up to 21,000 W across 3 MPPTs (2/1/1 strings)
Total Energy ≈21.6 kWh (4 × 5.4 kWh eFlex)
Enclosures Envy: NEMA 4X/IP65 • eFlex: IP65 • DuraRack: IP65
Primary Enclosure Size DuraRack 29.88 W × 41.97 H × 17.83 D in (cabinet footprint)
Approx. Combined Weight 712 lb (Envy 127 + 4× eFlex 108 + DuraRack 153.2)
Certifications Envy: UL1741/UL1741SB, IEEE 1547A • eFlex: UL9540, UL1973, UL9540A • DuraRack: IP65 cabinet; DuraRack + eFlex listed in UL9540/9540A documentation

Specifications from Fortress Power datasheets and manuals. Always size conductors/OCPD, provide clearances, and commission per the installation manual and local code/AHJ requirements.

SKUPES-SPS-SIV-0789
MPNEnvy12KW4-DuraRack
ManufacturerFortress Power
Container price$3,045,519.00 USD
Container qty200
Height41.97
Isfollowtrue
Isindextrue
Length17.83
Pallet price$172,579.41 USD
Unit price$20,303.46 USD
Width29.88
ManufacturerFortress Power
Model numberG2

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    Fortress Envy 12 kW + four eFlex 5.4 G2 in DuraRack
    Envy 12kW 1-Phase Energy Storage System – 4 eFlex 5.4 G2 Modules, DuraRack - Envy12KW4-DuraRack $16,716.09

    Specifications

    Datasheet
    Capacity Kwh 233
    Capacity Ah 280
    Voltage 832V (nominal); range 728.5-936.4V
    Chemistry LFP Prismatic
    Depth Of Discharge 90%
    Cycle Life >6000 @ 25°C
    Certifications<