CYGNUS 4 >Connect to diesel gensets <250 kVA

Product Overview

The ‘All New’ Cygnus® 4 is the largest capacity hybrid power system of its kind available on the market today.

Designed for use with diesel generators of up to 250 kVA, Cygnus® 4 can manage load spikes of up to 42 kVA without triggering auto start of a diesel generator.

Cygnus® 4 boasts the latest in cutting edge OPzV storage technology, with double the life of standard AGM storage technology, or the option of LFP storage technology. Either option delivers the fastest return for hire operators and the most savings to end users in fuel, noise, CO2, NOx and PM on-site emissions from Firefly’s Cygnus® range. Over the product lifetime of Cygnus® 4 potential savings of up to 1160 tonnes of CO2 emissions can be saved.

With up to 130 kWh of energy storage, Cygnus® 4 delivers silent power for higher base loads than ever before.

As with all Firefly hybrid power systems, Cygnus® 4 works seamlessly with GLOW RFM® cloud platform to allow control, diagnostics and reporting from anywhere in the world.

Cygnus® 4 – the most advanced silent hybrid power system available on the market today.

Applications and Benefits


Whilst connected to a diesel generator, Cygnus 4 provides base load management, reducing the runtime of the diesel generator. As a result, noise, CO2, NOx and PM are significantly reduced. Over the product lifetime of Cygnus 4, up to 1160 tonnes of CO2 emissions potentially can be saved.

In addition, the frequency of servicing the diesel generator is reduced, whilst also providing back-up power in the event of generator breakdown.


Cygnus 4 can be specified at point of purchase to enable connection to a Solar PV system of up to 14 kWp with Firefly’s Solar-Pack™ (instead of or in addition to a diesel generator). Further reducing fossil fuel dependency whilst delivering silent off-grid power when configured as a standalone system.


Cygnus 4 applications are not limited to, but include silent power for:

  • Large Site Compounds
  • Drying Rooms
  • Cranes
  • Pumping
  • Utilities
  • Infrastructure

Learn more about the applications and benefits for your sector by following the links below.

construction link
events link
AID link



  • Variable RCD Earth Fault Protection
  • MCB Over Current Protection
  • Limit Switch – cuts power if access door is opened
  • Emergency Stop 
  • Lockable Service Doors
  • Lockable Control Panel Door


  • GLOW RFM® 
  • 125 A CEE Form 3 Phase
  • Busbar Wiring Options
  • 16 A Maintenance Charge Circuit
  • Binding Posts for Remote Generator Start/Stop


  • Digital Timer
  • Reinforced Forklift Pockets
  • Lift and Drag Skid
  • Rotating Lifting Ring
  • Compact Design


  • Built to ISO:9001 Quality Management System
  • Premium Quality Components
  • Rental Specification
  • IP55 Rated Toughened 3mm Zintec Steel Canopy



Cygnus 4 is available in three configuration options:

  • LFP (Lithium Iron Phosphate)
    Storage with 98 kWh and 48 kVA power output
  • LFP (Lithium Iron Phosphate)
    Storage with 130 kWh and 48 kVA power output
  • OPzV (Tubular Technology)
    Storage with 90 kWh and 48 kVA power output.

Learn more about our storage technologies and which one is right for you here.


Technical Downloads

Hire / Purchase

Cygnus 4 can be hired from our extensive partner network across Europe. Click here to find a hire partner. Hire today – click here

Alternatively Cygnus 4 can be purchased directly from the manufacturer, give us a call or drop us a line using the details below: +44 (0)800 091 4090

All Cygnus models are sold with a comprehensive 5-year Firefly warranty as standard, view our warranty page for further information.


  GLOW screens battery technology construction symbol events symbol aid symbol

Website Newsletter Sign Up
First Name*
Last Name*
Company Newsletter
Aid & Development Newsletter
Construction & Plant Hire Newsletter
Festivals, Events & Broadcast Newsletter