The energy company IWB is planning to install one of the largest heat pump systems in Switzerland using water from the Rhine river, reported SRF this week. The new facility is expected to heat around 5,000 homes in Basel.
Such water-based heat pump technology is already being deployed in other locations in Switzerland. In the city of Biel water will soon be drawn from Lake Biel and used to heat 2,200 apartments. The system then sends slightly cooler water into the Zihl river. This heat pump system is expected to be turned on next spring.
Another in Lake Geneva that heats 400 homes was completed in 2016. Le News visited the inauguration of this system.
These water-based heat pump systems are made up of three elements. The first continually takes water from a lake or river using a heat exchanger to extract several degrees of heat from it before discharging the resulting cooler water. The second is a closed system which sends warmed water around in a loop through pipes to the buildings. The final part is heat pumps which are installed in all of the connected buildings. These heat pumps extract and compress heat from the warmed water in the loop.
The Rhine project is different from these projects in a few ways. Firstly, it is large. Producing heat for 5,000 homes is a lot for a single facility. Secondly, it is reusing an existing pumping station, which was originally used by the pharmaceutical industry. This will limit the amount of construction work required, essentially adding an element of up-cycling to the project.
Basel city is aiming to be carbon neutral by 2037.
SRF article (in German)