The Most Cost-Effective Backup Power Available Runs Clean

The Altergy Fuel Cell Engine:
The unquestioned workhorse and durability leader
Altergy’s FCE is the original breakthrough clean backup power solution, and has provided critical power to telecom operations, emergency response, and military applications for more than a decade. The FCE features Altergy’s revolutionary Freedom Power Technology design and stainless steel construction, and delivers power conditioning and regulation capabilities that increase efficiency and keep electricity flowing to meet demand.


Alterg’s Freedom Power fuel cell engines are available standalone or in combinations with modular power cabinets from 1kW – 100kW.





The Altergy Nacelle:
Super compact for extreme deployment flexibility

Altergy’s Nacelle is the most compact, lightweight, and durable hydrogen fuel cell backup power system available. Ideal for rooftop installation and space-constrained high-density urban centers, the Nacelle can be deployed almost anywhere and provides extended runtimes with minimal maintenance effort. Altergy’s Nacelle dramatically reduces the footprint, weight, and cost of backup power.  It consists of an Altergy FCE engine featuring Freedom Power Technology and an integrated all weather enclosure.  The Nacelle can be cabinet mounted, shelter mounted, wall mounted, door mounted, or pole mounted.

Interested in a custom TCO analysis for your company?

Nacelle Model:



Altergy Freedom Power System – Nacelle

Model Number

FPS – 148N

FPS – 2.5 48N

FPS – 548N

Output 1

Rated Standby Power (kW) 1

1 kW

2.5 kW

5 kW

Nominal Current (A)





Rated (VDC)





Dimensions (W x D x H in.)

16” x 47” x 17”

21” x 47” x 17”

Weight (lbs)

240 lbs

280 lbs

420 lbs



Type and Grade

Gaseous hydrogen, industrial grade 99.95% pure (CGA-G-5.3 Type !, Grade B)

Supply Pressure

40 to 100 psig / 2.75 to 6.89 bar


Various, Unlimited with Altergy Freedom Fuel service


Operational 1

Ambient Temperatures 2

-40°C to +50°C

Relative Humidity

5% to 95% non-condensing


Indoors with suitable air management or outdoors with suitable enclosure


10,000 ft




Control Electronics

Supervisory Control

32-Bit Digital Signal Controller w/on-board, real time diagnostics, communications, thermal & systems management. Sensor less brushless direct current motor control

Power Conditioning

Fully digital, multi-phase, interleaved DC/DC converter

Monitoring Software

Real time control communicates with GUI to provide system and site status and allow user input of operating parameters. Field upgrades through communication port

I/O Interfaces 3

Ethernet supported. Four user-defined dry contacts. Optional wireless monitoring. Optional RS- 232, RS-485 and additional user defined contacts


Fuel pressure, leak detection, ambient temperature & humidity, stack & electronics temperatures, fan & filter conditions, stack & output currents and voltages, tampering





California Air Resources Board (CARB) certified as a zero emission electrical power generator. By-product is water


Recycles residual heat to increase fuel and system efficiency. Can use “Green” hydrogen fuel (generated from biomass, hydroelectric, solar or wind powered electrolysis)


<60dBA @ 3 meters

Safety/Certification/Compliance 4

Designed and tested to NEBS Level 3 criteria and certified under CSA FC-1, 2012


    • Altergy Fuel Cell Engines can be combined to achieve up to 100 kW of output.
    • 10 °C (50 °F) and below requires low temperature configuration, 40 °C (104 °F ) or higher requires high temperature configuration.
    • I/O Options Vary by model number
    • Some certifications pending.

Specifications subject to change without notice

Altergy’s Hydrogen Fuel Cell Features
  • Lower Initial Cost – Altergy’s patented design reduces critical component costs by more than 80%, which reduces capital expenditure significantly compared to batteries or generators
  • Lower Total Cost – Altergy fuel cells feature rugged components and no moving parts in the cell stack, leading to lower maintenance costs and lower total cost of ownership
  • Clean Performance – Altergy fuel cells are certified by the California Air Resources Board as zero emission power generators
  • Proven Durability – Altergy replaces graphite and fragile components used in conventional fuel cells with stainless steel and highly durable components able to withstand severe environments
  • Compact Footprint – Altergy fuel cells take up less space than traditional fuel cells, batteries, or generators, providing greater deployment flexibility
  • Lightweight Construction – Revolutionary design and construction make Altergy fuel cells ideal for rooftop installations
  • Quiet Operation – With no moving parts and no internal combustion, Altergy fuel cells operate at a barely audible hum
  • Scalable – Plug-and-play feature allows scalability for applications from watts to megawatts
  • Fast Start-Up – Altergy fuel cells start up in about 10 seconds
  • Easy Maintenance – The primary maintenance is replacing air filters once a year
  • Simple Installation – Altergy fuel cells reduce backup power installation from days to a few hours
  • Long Life – Altergy fuel cells have a design life of more than 20 years


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