US-based FlexGen Power Systems has acquired Clean Energy Services (CES), adding battery energy storage system (BESS) and utility-scale solar services to its operations as it seeks to expand project delivery and system support.
The deal brings CES’ commissioning and lifecycle service teams into FlexGen and adds authorised service provider (ASP) capabilities to the company’s OEM partner programme.
The acquisition will support faster delivery of BESS projects, improve system performance and strengthen long-term asset reliability for customers.
CES’ solar servicing work will also extend support for FlexGen’s HybridOS Solar PPC offering for solar and hybrid assets.
Co-founded in 2022 by Ahmad Atwan and Constantine Triantafyllides, CES will operate as CES, a FlexGen subsidiary.
Existing CES customers will continue to receive the same services from CES. They will also be able to use FlexGen HybridOS, an energy management system that combines controls, analytics and data access on one platform.
CES will keep running its remote operations centre (ROC) in Houston, Texas, which covers more than 1GW of solar and 4.5GWh of batteries.
FlexGen will continue to operate its ROC in Durham, England, providing round-the-clock monitoring, root-cause analysis and field service dispatch.
FlexGen CEO Kelcy Pegler: “The addition of CES strengthens our service platform and reinforces our leadership in energy storage technology.
“By pairing best-in-class lifecycle services with HybridOS and Solar PPC, FlexGen is positioned to deploy faster, operate better, and deliver sustained value for our customers.”
The transaction broadens FlexGen’s service offering across utilities, independent power producers and data centres.
The company said the combined business will support battery system deployment and system reliability across battery and hybrid assets.
FlexGen has more than 15 years of integration experience and delivers 98% system availability.
In August 2025, FlexGen completed the acquisition of Powin’s assets and intellectual property (IP).
