Fortress Power FlexTower Energy Storage System (81.0kWh Capacity)

SKU: 450-0193

Fortress Power, Flex-Tower for 1 Sol-Ark 12 or 15kW Inverter (NOT included) Stacks On 1 DuraRack Battery Enclosure, UL9540, UL9540A, IP65/3R Enclosures, FlexTower



The FlexTower is an all-in-one energy storage system. Built on the foundation of the DuraRack battery cabinet, the FlexTower combines the battery, charge controller, and inverter into a single unit with an LCD control panel, and remote monitoring capability. The FlexTower is easy to install and carries IP65/NEMA3R ratings for indoor or outdoor use.


All-in-One Solution

  • Inverter, charge controller, LCD Control Panel, Battery and remote monitoring app integrated in one unit
  • Supports Off-grid, Back-up, Zero Export, Time-of-Use, Demand Response, Peak Shaving, and Virtual Power Plant


Flexible & Easy Install

  • IP65 water and dust proof for indoor & outdoor installation. NEMA3R
  • AC or DC couple to existing or new PV arrays
  • Optional Rapid Shutdown Button Included
  • Side knockouts sized for solar, grid, and generator wiring


Highest Reliability for Maximal Protection

  • 8000+ cycle life with tier 1 Automotive Lithium Iron Phosphate (LFP) battery
  • Easily scaled to meet all large residential and commercial electricity needs


Whole Home Backup with 200A Grid Pass-through

  • 200A Pass-through eliminates backup panel requirement
  • Saves time on inverter wiring
  • Includes battery cables and combiner for additional savings


Highest Roundtrip Efficiency to Maximize Your Solar Investment

  • >98% Battery Efficiency
  • 5% CEC-Rated Inverter Efficiency
  • Compatible with Din-Rail Heaters to maximize lifecycles in cold climates




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