Swiss energy company Alpiq has agreed to acquire a 90% stake in Harmony Energy, a developer and operator of grid-scale battery energy storage projects across Europe.

The acquisition will expand Alpiq’s battery storage portfolio and provide access to Harmony Energy’s project development, construction, operations, and asset management capabilities. The companies did not disclose the financial terms or expected completion date.

Post the transaction’s completion, Harmony Energy will continue operating independently under its existing brand. It will retain its employees, organizational structure, and operating model.

Harmony Energy has a multi-gigawatt pipeline of battery storage projects across the U.K., Germany, France, and Poland. The acquisition will add approximately 400 MW of projects under construction to Alpiq’s European battery storage portfolio. The assets include a project in the U.K. that is expected to connect to the grid as early as the third quarter of 2026.

“Partnering with Alpiq marks an exciting new chapter for Harmony Energy. With Alpiq’s financial strength, market expertise and pan-European footprint, we are well positioned to scale our project pipeline while ensuring continuity for our team and partners,” Peter Kavanagh, co-founder and CEO of Harmony Energy.
Alpiq said the transaction supports its strategy to expand its flexible energy assets and commercial capabilities as European power systems integrate more renewable energy. Battery storage systems absorb electricity when supply exceeds demand and discharge it when additional power is needed.

Alpiq had earlier acquired two battery storage projects from Harmony Energy, including the 100 MW Cheviré project in France.

Harmony Energy has delivered 18 grid-scale battery storage projects with a combined power capacity of more than 700 MW. The company has capabilities in project development, construction, and operating asset management.

Harmony Energy may also continue selling selected projects or operating assets to third-party investors, a model it has used for some projects.

Alpiq said the projects under construction and Harmony Energy’s development pipeline would support its plans to build and operate a multi-gigawatt battery storage portfolio in Europe.

According to Mercom’s Q1 2026 Funding and M&A for Energy Storage report, corporate M&A activity increased, with seven companies acquired in the first quarter of 2026 compared to only one in Q1 2025.

In July 2026, Royal Vopak, a company that owns and operates infrastructure for the storage and handling of liquids and gases, acquired a 79% stake in Green Energy Storage and took a final investment decision for a 200 MW/800 MWh battery energy storage project in Oosterhout, The Netherlands.