Alpiq has acquired a 90% stake in Harmony Energy, adding a multi-gigawatt pipeline of projects across the UK, Germany, France and Poland.

NPM Europe reported in May that Alpiq had submitted an offer to acquire UK-based battery energy storage developer Harmony Energy.

Financial terms of the transaction were not disclosed.

Following completion of the transaction, Harmony Energy will continue operating under its existing brand and management structure.

Co-founder and CEO Peter Kavanagh will remain in his role and retain a 10% shareholding, while Alpiq head of BESS Christoph Bellin will join Harmony Energy’s management board while continuing his position at Alpiq.

Harmony Energy may also continue to sell selected projects or assets to third-party investors.

The acquisition adds approximately 400 MW of BESS assets under construction to Alpiq’s portfolio, including a UK project expected to be connected to the grid in Q3 2026.

The companies had already established a business relationship through the sale of two French battery storage projects. Alpiq acquired the operational 100 MW / 200 MWh Cheviré BESS facility in the Nantes Saint-Nazaire port area in January and the 100 MW / 200 MWh Marronniers BESS project in the L’Oise department in 2025.

Harmony Energy has delivered 18 grid-scale BESS projects with a combined capacity of more than 700 MW and has operations spanning project development, construction and asset management.

The company’s pipeline includes battery storage projects in several European markets.