225kw to 1.8MW

The Active Power CLEANSOURCE® XT SMS is the perfect combination of low total cost of ownership, superior reliability, and sustainability for any mission critical application. CLEANSOURCE® XT SMS provides 78% more runtime than the CleanSource 300, delivering one minute at typical industry loads.



TCO Savings


Times Less Likely to Fail


Less Carbon Emissions

A Great Fit

  • Permanent energy storage
  • 98% energy efficient
  • Less expensive to install and commission
  • Most reliable energy storage system
  • Minimize risk and disruption from maintenance and replacement
  • 90% less carbon used in UPS manufacture
  • Over 40% less carbon emitted over 15 years
  • Longer runtime in same compact footprint
  • Parallel capability up to 2MW
  • Wide operating temperature range


Data Center

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Health Care

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Industrial & Manufacturing

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40% TCO Savings

Total cost of ownership (TCO) is the key metric in determining the economic value of your UPS. Active Power’s solutions are designed to deliver the lowest possible TCO compared to legacy battery-based solutions – up to 40% lower TCO over your facility’s life. Our systems will save you millions over 15 years.

  • Integrated solution – saves on installation and support infrastructure
  • Highest efficiency – up to 98% energy efficient with full power quality protection
  • Permanent energy storage – no batteries to install, monitor, service, or replace

12 Times Less Likely to Fail

The first job of a data center is to stay online. To that end, your UPS should improve the reliability of your data center, and not put it more at risk. With CleanSource UPS, the flywheel is spinning constantly, storing kinetic energy. When called upon during a utility outage, the flywheel is ready to assume the load. By contrast, battery failures are the leading cause of UPS load loss and system downtime. Consequently, Active Power’s UPS system is proven 12 times less to likely to fail than a battery-based system.

90% Less Environmental Impact

Data centers are inherently energy-intensive – consuming up to 50 times the electricity per square foot than a standard office space. That energy can generate a tremendous amount of pollution and carbon emissions from fossil-fuel based power plants. Battery-based UPS’s waste too much electricity, and require thousands of pounds of lead to be installed, replaced, and recycled over their life.

Active Power’s solution can help. Energy efficiency and permanent energy storage combine to make Active Power the smart and responsible choice for the environment, saving thousands of tons of carbon from being emitted:

  • Up to 90% less carbon used to manufacture of our flywheel vs lead-acid batteries
  • 40% less carbon emitted over the life of the product

A Great Fit

Mission critical facilities are different than other environments and present special challenges. Temperature, airflow, space, and safety all need to be considered carefully before equipment can be deployed. Active Power’s solutions are a great fit for these applications.

  • 78% increase in flywheel runtime delivering one minute at typical industry loads
  • Smallest footprint - Active Power’s systems take up to less than half the space of typical battery UPS systems
  • Highest temperature range – Our systems can support up to 40C environments with no degradation in performance
  • Most reliable – CLEANSOURCE® XT SMS has been proven to be 12x less likely to fail than battery based systems
  • Less maintenance – reduces disruption and risk
  • 40% reduction in TCO compared to battery alternatives
  • Green – improve sustainability by 90% compared to battery based systems


Flywheel 101

What makes CLEANSOURCE® systems so special? The answer is Active Power's patented integrated flywheel UPS technology. Flywheel systems store kinetic energy - energy produced by motion - by constantly spinning a compact rotor in a low-friction environment. When short-term backup power is required because utility power fluctuates or is lost, the inertia allows the rotor to continue spinning and the resulting kinetic energy is converted to electricity.

Replaceable Bearing

Field Windings

Steel Flywheel,

Motor-generator Rotor

Armature Windings

Operates In a Vaccum

Parallel Online Architecture

CLEANSOURCE® XT SMS uses a battery-free power module as the basic building block. Each module is rated at 250kW for 480V systems and 225kW for 400V systems. One or more of these modules are combined with an automatic bypass, grounding transformer and various options such as static switch bypass and maintenance bypass to make a complete UPS system.

Power Quality

CLEANSOURCE® XT SMS provides clean, reliable power to your data center, protecting operations against all types of disturbances. CLEANSOURCE® XT SMS samples the electrical input 333 times every cycle or once every 50 micro-seconds and eliminates every transient using its static switch, line inductance, line capacitance, active filtering, power converters and flywheel energy storage. The system senses voltage deviation from nominal and immediately corrects back to the prevailing nominal. Upon a complete loss of input power or a major deviation in input voltage or frequency, the UPS will disconnect from the utility source and flywheel energy will be used to support the load at nominal voltage until the backup diesel generator comes online.

Service & Maintenance

CLEANSOURCE® XT has been designed with ease of maintenance in mind. It requires only simple and non-invasive annual maintenance and a bearing change every fourth year – there's no need for quarterly inspections or a complete replacement every 3 to 5 years that typical battery-based systems require. All recommended maintenance is performed by a factory-certified service engineer in the field. In the case of our multi-module systems, we can perform maintenance on one flywheel while the other flywheels are online and protecting the load. Active Power offers three flexible service plans designed to meet individual customer needs.