Large solar thermal plant on Föhr goes into operation

03.07.2025

Source: E & M powernews

A new large-scale solar thermal plant is being built on Föhr. In future, it will cover around a quarter of the heat requirements of Energiegenossenschaft Föhr eG.

A solar thermal plant with a total area of more than 3,000 square meters is being built on the island of Föhr (Schleswig-Holstein). In future, it will provide around 1 million kWh of heat for the district heating network. This corresponds to a renewable energy share of more than 23 percent of Energiegesellschaft Föhr eG's total heating requirements.

Construction of this large-scale solar thermal plant began on the North Sea island of Föhr at the beginning of February 2025. Energiegenossenschaft Föhr commissioned Viessmann Germany with the planning and implementation. The contract included the construction of a turnkey system including a 500 cubic meter buffer storage tank and a prefabricated technical building for control and heat generation. The system will now go into operation in the course of July, Viessmann clarified on July 2 when asked by this editorial team.

The aim of the project is to achieve a long-term reduction in CO2 emissions in the heating sector on Föhr. All of the heat generated will be fed into the local district heating network. The high proportion of renewable energies should not only reduce the island's ecological footprint, but also achieve a more stable heat supply price. The energy cooperative plans to use the new infrastructure to secure a large proportion of its annual heating requirements for at least 30 years.

Viessmann Deutschland GmbH is part of Viessmann Climate Solutions, which in turn has been part of Carrier Global Corporation, a leading global provider of climate and energy solutions, since January 2024.

Large-scale solar thermal only growing slowly

In general, large-scale solar thermal is waiting for a leap in growth nationwide. According to a list by Solites, a Stuttgart-based Steinbeis research institute for solar and sustainable thermal energy systems, around 10,000 square meters of gross collector area were added in Germany last year (we reported).

However, Solites predicted in April of this year that the current level would more than double by 2026. In spring 2025, there were 61 solar heating networks in operation. They have a gross collector area of 173,275 square meters and a solar output of around 121 MW.

According to Solites, the growth up to 2026 is due to 16 commissioned systems, some of which are already under construction. Once commissioned, they will be included in the statistics with an additional 193,108 square meters of gross collector area. The lion's share is accounted for by plants under construction in Leipzig (65,000 square meters), Bad Rappenau (28,871), Stralsund (24,361), Steyerberg (13,700) and Tübingen (12,172).

Author: Heidi Roider