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eSpire 306
Scalable, Utility-Grade Energy Storage

A high-voltage, high-capacity solution designed for commercial and industrial applications — from peak shaving to grid services and backup power.

eSpire 306 Energy Storage System

Commercial + Industrial Battery Storage

The eSpire 306 is Fortress Power’s flagship commercial energy storage system, offering up to 554 kWh of capacity and advanced control features for grid support, peak shaving, and backup power. Designed for large-scale facilities and microgrid integration, it delivers reliability, flexibility, and long-term value

Applications

Multi-Family Homes

Grocery and Convenient Stores

Charging Stations and Service Areas

Schools, Banks and Hospitals

FEATURES

  • Safe Technology & Multi-level Protection

    The solution uses the best-in-class Tier 1 Lithium Iron Phosphate (LFP) chemistry for the highest level of safety, thermal stability, and reliability; An integrated, multi-level Battery Management System (BMS) monitors, optimizes, and balances the system.

  • Advanced Liquid Cooling for the Extended Battery Lifespan

    The unique liquid cooling system optimizes the battery thermal performance by 3 times, which extends the battery lifespan and increases your investment.

  • Built-in Microgrid Controls with Adaptive EMS / Fleet Management

    Ability to integrate with solar, genset, wind, micro-turbines, utility, or other distributed energy resources. Intelligent software to reduce electricity cost, prepare for resiliency, and maximize return on investment. Remote operation & maintenance.

  • Easy & Flexible to scale

    This outdoor rated, modular solution can be expanded up to 6.1 MWH capacity easily (Max. 20 unit in parallel).

  • Turnkey System for Fast Install

    Fully integrated, pre-configured package system reduces on-site installation time; includes inverter(s), battery trays, racks, BMS, microgrid Controller, HVAC, fire suppression, and outdoor rated enclosure. Off-grid and back-up package available.

  • Excellent Local Support

    Our US based technical support team can help you from project design to completion.

PRODUCT INFORMATION

Battery Specification
Fortress Power Battery ModuleeSpire 306
ChemistryLithium Iron Phosphate
Cell TypePrismatic
Pack Configuration1P52S
Number of Modules6
Nominal Capacity306 Ah
Nominal Energy305.5 kWh
Nominal Voltage998.4 Vdc
Operating Voltage Range873.7 – 1123.2 Vdc
Maximum Continuous Charging/Discharging Current153 Amps
CommunicationModbus TCP, CAN, Modbus RTU
Cycle Life @ 25C @ 70% Retention10,000 Cycles
DC DC Round Trip Efficiency95% @ 0.5C, 25°C, 1 Cycle Per Day
Operating Temperature RangeCharging: 0-55°C & Discharging -20-55°C
Thermal Management SystemIntegrated Liquid Cooling System (HVAC)
Fire Suppression SystemFire Detector, Smoke Detector & Fire Extinguisher
IP ClassType IP66, NEMA 3R
Battery Bank ScalabilityUp to 20 (6.1 MWH)
PCS Specification
PCS ModelFP-PCS125HV
Rated AC Power125 KVA/KW
Rated Grid Voltage3Ph 480Vac + PE
Grid Voltage Range422 to 528Vac (-12%, +10%) / (3Ph 208Vac) * + PE *
Rated Grid Frequency60 Hz
Grid Frequency Range59.3 to 60.5Hz, Adjustable
Rated AC Current151 Amps
DC Voltage Range750-1350Vdc
Rated Discharge / Charge Power128KW/122KW
Max. Discharge/Charge Current157Amps/151Amps
Current THD<3%
Power Factor-1 to 1, continuously adjustable
Peak Efficiency98%
Standby Loss<25W @ Cool Mode
Grid Power Factor-1 (leading) to (Lagging), Continuously Adjustable
Wiring Configuration3 Phase 4 Wire or 3 Phase 3 Wire (3P4W/3P3W Configuration)
ProtectionDC Reverse Protection/OVP/UVP/OCP/DC Insulation Detection

* For 3Ph 208Vac + PE application, a step-down transformer is required.

Energy Management Software
Functional OperationReal-time Monitoring, Adaptive Peak Shaving, Demand Response, Net Metering, VPP
Operation ModeBack-up, Microgrid, Off-grid, Time of Use, Zero Export, VPP
Communication InterfaceModbus (TCP and RTU), TCP/IP, CANbus, BACnet, Dry Contactor, External APIs
System SpecificationPCS DetailsKeystone Microgrid Control PanelBattery Details
Operating Temperature-22 to 140°F, De-Rating >113°F (-30 to 60°C, De-Rating >45°C)

-22 to 131°F

(-30 to 55C)

-22 to 113°F

(-30 to 45°C)

Storage Temperature Range

-13 to 131°F

(-25 to 55°C)

-22 to 131°F

(-25 to 55C)

-20 to 140°F

(-40 to 60°C)

Dimensions (H*W*D)

78.74 x 23.62 x 19.685 in

(2000 x 600 x 500 mm)

77.56 x 35.43 x 36.06 in

(1990 x 900 x 916 mm)

89.76 x 51.18 x 51.18 in

(2280 x 1300 x 1300 mm)

Enclosure RatingNEMA 3R / IP55NEMA 3R / IP54NEMA 4X / IP56
Relative Humidity<95% No Condensing<95% No Condensing<95% No Condensing
Max Altitude3000m, De-Rating > 2000m3000m, De-Rating > 2000m3000m, De-Rating > 2000m
Acoustic Noise<70 dBA, Max 75dB<70dB<70dB, Max 80dB
Cooling SystemForced Air via Speed ControlAir CoolLiquid Cooling Via HVAC
Net Weight286.6Ibs (230 kg)690 lbs (313 kg)6500 ± 220 lbs (3005 ± 100 kg)
Operation Status indicatorsWarning, Low Voltage & High Voltage
Lockage EnclosurePadlockable Swing Handle
User InterfaceLED, EPO, Ethernet & HMI via Web Access / EMS Web Portal
Communication ProtocolEthernet/Modbus TCP
CertificationsUL1973, UL9540[A], UL1741-SB, IEEE-1547-2018, IEEE-519, FCC Part 15 Class A, UL9540, CEC, SGIP, OGPe

Warranty

Data Sheets

espire diagram

Keystone EMS

The Keystone EMS cloud platform and microgrid controller secures your energy using advanced tools, including:

  • Automated scheduling and controls
  • Integrated controls for solar, storage, EV charging, generators, and other devices
  • Real-time insights and monitoring
  • O&M reporting and alarming tools
  • Scalable from individual projects to portfolios of assets

C&I Checklist Form

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