Active Power
AcquiredAustin, US · Founded 1992 · 360 employees on LinkedIn · 2 known investors
Active Power designs and manufactures flywheel-based uninterruptible power supply (UPS) systems and turnkey power solutions for enterprise customers requiring critical power protection. The company serves operations across more than 50 countries with manufacturing based in Austin, Texas.
Also known as Active Power Inc. · Active Power, Inc.
Investors · 2
Company profile
researched Aug 2026Active Power Inc. designs and manufactures battery-free flywheel uninterruptible power supply (UPS) systems and kinetic energy storage products for mission-critical power applications. Its core CLEANSOURCE flywheel platform stores kinetic energy in place of chemical batteries, and is marketed on efficiency, reduced maintenance and lower total cost of ownership relative to battery-based UPS systems. The company also supplies turnkey and factory-assembled power solutions and generator starting equipment.
The product line spans CLEANSOURCE PLUS SMS (stand-alone flywheel UPS from 300kW, parallelable to 2,667kW), CLEANSOURCE PLUS MMS (modular, 300kW to 2,667kW), CLEANSOURCE XT (modular, 225kW to 2,000kW), CLEANSOURCE HD (stand-alone high-density, 675kW to 5,400kW), POWERHOUSE factory-assembled plug-and-play enclosure UPS solutions, and GenSTART, a generator starting module that removes the need for starter batteries. Alongside equipment sales, Active Power offers installation, maintenance and repair services through a global support team, plus a UPS rental service for urgent backup power needs.
Active Power targets sectors including data centers, pharmaceuticals, military and defense, transportation, industrial and manufacturing, leisure and entertainment, healthcare, and broadcasting and communications. Manufacturing and product testing take place at an ISO 9001:2015-certified facility in Austin, Texas.
Business model
Active Power sells flywheel UPS systems, enclosure-based power solutions and generator starting modules to enterprise and industrial end users, complemented by aftermarket installation, maintenance, repair and equipment rental services. Its UPS design emphasizes non-invasive annual maintenance and periodic bearing changes rather than frequent battery inspections.
Revenue derives from sales of flywheel UPS and energy storage hardware and turnkey power solutions, together with service contracts covering installation, maintenance and repair and a UPS rental offering.
Traction
Reported installed base figures include more than 7,500 flywheels installed globally, over 70,000 years of flywheel runtime and more than 1,400 MW of critical power protected. In a 2024 project for electric vehicle manufacturer Tesla, Active Power supplied two 2.4MW CleanSource PLUS MMS UPS units, each protecting a 3000A production line, plus a 333kW CLEANSOURCE PLUS SMS unit replacing a 15-year-old battery UPS; the project was described as a potential first step among eight planned 4.8MW installations for the manufacturer.
Latest developments
Company news items note the release of parent company interim financials in August 2026 and the appointment of Dean Richards as Co-CEO of Piller in April 2026. The Austin plant is described as capable of producing more than 300MW of flywheel UPS annually, with 7,500kVA of total test capability, and the company was recruiting a power electronics engineer.
▸Full profile — market position, technology, go-to-market, geography, history
Market position
Active Power positions itself as a pioneer in battery-free flywheel UPS and cites more than 7,500 flywheels installed globally, over 70,000 years of cumulative flywheel runtime and more than 1,400 MW of critical power protected. Following its 2016 acquisition, its kinetic energy UPS technology broadened the Piller group's power protection portfolio as an alternative to traditional UPS offerings.
Battery-free operation is the principal point of differentiation: the flywheel systems avoid battery rooms and the monthly or quarterly battery inspections associated with chemical UPS, requiring instead non-invasive annual maintenance and occasional bearing changes, with claimed benefits in efficiency, footprint, environmental impact and total cost of ownership.
Technology
The company's CLEANSOURCE flywheel technology stores energy kinetically and releases it rapidly to bridge power disturbances, avoiding chemical batteries. Systems are built on a fault-tolerant IGBT architecture, and are offered in stand-alone, modular and high-density configurations from 225kW up to 5,400kW, with parallel operation supported.
Go-to-market
The company sells directly through its sales and system engineering teams, supported by a worldwide service organization, and reaches international markets via Piller's subsidiaries and service centers. It maintains a presence at industry trade events including Data Centre Expo North America, the ASHE Health Care Facilities Innovation Conference, Datacloud USA, Data Center World Power and Semicon West.
Mission-critical facility operators across data centers, pharmaceutical production, military and defense sites, transportation systems, industrial and manufacturing plants (including electric vehicle production), casinos, theme parks and shopping malls, healthcare facilities, and broadcast and communications operations.
Geography
Headquarters, manufacturing and product testing are in Austin, Texas, in a facility of more than 135,000 square feet. Active Power protects operations in more than 50 countries; US customers are served from Austin and international customers via the Piller global network of subsidiaries and service centers.
History
Active Power's About page states the company was founded in 1996 and became public on NASDAQ in 2000; a company news post gives the IPO year as 2001. In November 2016 the business and assets were acquired by Germany's Piller Power Systems, a subsidiary of UK engineering and industrial group Langley Holdings plc. Active Power now operates as a member of the Piller Power Systems group, serving US customers from Austin and international customers through Piller's network of subsidiaries and service centers.
Compiled by commissioned research from 8 cited public sources — announcements, filings, and press listed under research sources below.
Key figures
latest reportedCompany-reported or press-reported figures, each dated to when it was claimed — not independently audited.
Competitors · 2
by search overlap
Companies competing with Active Power for the same Google search keywords, organic and paid, via search-intersection analysis.
Timeline · 4
launches, deals, and filingsCompany news item announcing the appointment of Dean Richards as Co-CEO of Piller, Active Power's parent group.
Active Power supplied two 2.4MW CleanSource PLUS MMS flywheel UPS systems, each protecting a 3000A production line, allowing the customer to forgo an ATS and diesel generator; a 333kW CLEANSOURCE PLUS SMS unit was also supplied to replace a failed 15-year-old battery UPS. The project was described as the potential first of eight planned 4.8MW installations.
The business and assets of Active Power Inc. were acquired by German group Piller Power Systems, a subsidiary of UK engineering and industrial group Langley Holdings plc. US customers continue to be served from Austin, Texas, with international coverage via Piller's network of subsidiaries and service centers.
Active Power's About page states the company became public on NASDAQ in 2000; a company news post states 2001.
Dated company events from announcements, filings, and press; legal rows summarize public dockets and regulator releases.
In the news
▸Research sources · 8
primary sources listed
- Active Poweractivepower.com · web
8 public sources were cited for this profile; the first-party ones are listed here.
Frequently asked questions
- What does Active Power do?
- Austin-based maker of battery-free flywheel UPS systems for mission-critical power, now part of the Piller Power Systems group.
- Who are Active Power's investors?
- Active Power's investors include Rho Capital Partners, Rho Ventures.
- Where is Active Power headquartered?
- Active Power is headquartered in Austin, US.