District heating instead of gas: this is how cities should heat renewable energy sources in the future. But this is easier said than done, as the example of Lucerne shows.
Climate protection has been asking for it for a long time, the Ukrainian war and the resulting increase in energy prices have made the situation even more acute: many homeowners want to get away from oil or gas heating. “We feel it within us,” says Cyrill Studer. He heads the environmental advisory service for the city and the canton of Lucerne. Inquiries increased sharply: in the first months of the year there were 1,600 of them, in the same period of the previous year only 900.
Advice is not only needed, but also necessary. Switching to renewable energy is often not easy. This was also experienced by the Ecumenical Housing Cooperative Lucerne OeWL. It plans to renovate two of its residential buildings in Neustadt.
Legend: The old gas heating system will soon be obsolete. It is painted green, but from an energetic point of view, it is not. SRF
Both are currently gas fired. It is clear to the cooperative that they want to switch to green heating, says its CEO Florian Flohr: “We cannot just shift the responsibility for achieving the climate targets to the country. But we have to get involved. “
Difficult to find alternatives
For its two residential buildings, OeWL now wants to install a pellet heating system – a variant that is not very common in the city. It wasn’t my first choice either. Other variants were previously tested.
“There are two mirrors of water here that cannot be drilled through.”
The geothermal probe has not been approved: “There are two groundwater tables here that must not be drilled to prevent them from getting mixed up,” explains Flohr. There is also no possibility of drawing heat from the groundwater, because another large housing estate in the vicinity does it: “The reservoir is exhausted”.
Caption: In Kriens, the cooperative had to make improvements: air-to-water heat pumps with additional noise protection. OeWL
Another option would be a heat pump that uses fans to extract heat from the air. The system that the cooperative has already installed on the property in Kriens. So he has experience with that. Just not just a good experience.
“These heat pumps make a lot of noise, especially when they’re a bit bigger.” Therefore, they should have installed additional noise protection measures afterwards, says Florian Flohr. But even that wouldn’t be enough for your properties in the city of Lucerne: “It’s a closed courtyard and you can hear every sound here.” In other words, a heat pump was also out of the question.
The best option: the warmth of the sea
Finally, the option of district heating was discussed. This would actually be the best option for a densely built-up urban area – especially in Lucerne, where the municipal energy company EWL is building a large district heating network for the lake. However, it is not yet far enough for an ecumenical housing cooperative to join it now.
District heating pioneer in Basel
Open the box. Close the box
The city of Basel is considered a role model for district heating throughout Switzerland. Canton wants to expand the network for CHF 460 million and get rid of gas heating completely by 2035. The district heating network is already the largest in Switzerland – and its length is to increase from 130 to almost 200 kilometers. With the exception of individual estates of detached houses, virtually the entire city is connected.
That should change as soon as possible, says Cyrill Studer of an environmental consultancy. If you want to replace around 6,000 oil or gas heating systems in the city of Lucerne in a reasonable time, there is no way to bypass the large district heating networks. And for that you need to invest a lot and quickly.
Studer compares: “About 50 years ago, billions were invested in sewage systems and wastewater treatment plants. Today we are at a similar point where the inner cities need to be re-equipped for the future. ” This could happen until 2040. This date is envisaged in the climate strategy of the city of Lucerne. “I sense a great will when I talk to the council or associations. That’s why I’m confident. “