Alpiq Holding

The company was formed in February 2009 from the merger of Energie Ouest Suisse (EOS) and Aare-Tessin AG für Elektrizität (Atel).

In 2010, Alpiq became the largest open market electric power trader in Romania, surpassing Alro Slatina, and gaining a 16% market share.

From 2012 to 2016, the company's revenue fell by more than half and Alpiq incurred heavy losses in the area of hydropower. Acting as a wholesaler, the company was affected by a price drop in the wholesale market. Furthermore, unlike other renewable energies, hydropower was not supported by the state. Alpiq therefore announced its intention to sell 49% of the hydropower plants in March 2016, but no buyer was found.

Alpiq tried to sell its Swiss nuclear power plants to EDF in 2016, as the production costs of the nuclear power plants were higher than the electricity prices at the time.

In March 2018, Bouygues acquired Alpiq's energy services business for over CHF 800 million. Following disagreements over the final adjustment amount, arbitration proceedings ensued. This was terminated in 2020 and Alpiq refunded over CHF 50 million to Bouygues.

Until 2019, Alpiq owned two coal-fired power stations in the Czech Republic until they were transferred to investor Pavel Tykač's Seven Energy Group at the end of August 2019, as Alpiq increasingly focused investments on renewable energies. Through the sale of the coal-fired power station, the company reduced its CO2 emissions by 60%.

At a media conference in early April 2019, Alpiq announced that EDF was selling its Alpiq shares. The consortium agreement, which was to be terminated in September 2020, ended early. By the end of May 2019, EOS Holding and Primeo Energie each took over half of the share package, financed by a mandatory convertible loan from Credit Suisse. The aim was to delist Alpiq shares from the Six Swiss Exchange by means of a squeeze-out, and to split Alpiq's share capital. The delisting application was approved by Six Exchange Regulation on 26 November 2019 and the delisting was set for 17 December 2019. On the last day on the stock exchange, the share price was approximately CHF 70.

Since the mid-2020s, Alpiq has expanded into battery energy storage systems. In October 2025, the company commissioned its first wholly owned battery storage facility in Finland. It acquired another facility in France in early 2026 and a 90% stake in the British battery storage developer and operator Harmony Energy in July 2026.

Nuclear power plants

The company has interests in two nuclear power plants. Alpiq holds a 40% interest in the Swiss Gösgen Nuclear Power Plant (capacity, 1060 MW) and is in charge of management. It holds a 27.4% stake in the Swiss Leibstadt Nuclear Power Plant (capacity, 1165 MW). In 2016, Alpiq attempted to sell the nuclear power plants.

Hydropower plants

Reservoir and pumped-storage plants can respond to changes in demand and help stabilise power grids by supplying electricity when solar and wind generation is low.

Alpiq is involved in a number of hydropower expansion projects. Grande Dixence SA, in which Alpiq holds a 60% interest, is planning the Gornerli multipurpose reservoir above Zermatt, with a storage volume of around 120 million cubic metres. At the Moiry and Emosson reservoirs, the dams are planned to be raised by 9 and 10 metres respectively, which is intended to increase storage capacity by a total of more than 165 gigawatt-hours. In February 2026, Alpiq acquired the Navaleo pumped-storage project in Castile and León, Spain, with a planned capacity of 535 megawatts.

Storage power plants

The most important hydropower plants for Switzerland are the Grande Dixence Dam with a capacity of over 2000 megawatts, and the Nant de Drance Hydropower Plant with a capacity of 900 megawatts. With its capacity of 900 megawatts, the Nant de Drance is one of the most powerful pumped storage plants in Switzerland.