Heat pumps have a long history in Switzerland. Already in the 1870s a vapor recompression salt plant was put into operation, marking the start of both product and market development in the country. Since then, Switzerland has continued to contribute to the development of e.g. borehole heat exchangers, sewage heat recovery, oil free piston compressors and turbo compressors.
Initially, there was mainly a market for larger industrial chillers. This changed in the 1930s, when heat pumps were installed also for space heating and for low temperature heating purposes such as domestic hot water and water in public swimming pools. The driver behind this market increase was a coal supply shortage which caused a need for other solutions. One of these solutions was hydroelectric power plants. And that electricity could be used for heat pumps. Another factor behind Switzerland becoming a heat pump pioneer is the advanced mechanical and thermal engineering skills available in the country.
The next market increase came with the oil crises in the 1970s. Heat pumps for central heating in larger and smaller residential buildings were developed, and annual sales figures were typically between 2000 and 3000. Then, in 1993, the Swiss Association for the Promotion of Heat Pumps (FWS) was established, contributing to a rapid sales increase with a peak in 2007 with 20,670 units. A new sales record was set in 2018, and then again in 2019 with as many as 23,980 units sold.
Today, Switzerland is still a heat pump stronghold. Approximately 90 percent of new single-family homes were equipped with heat pumps in 2019. Of all heating systems sold in 2019, 40% were heat pumps. Despite that, fossil fuel-based heating systems supply almost 3.5 as much heat as heat pumps. The explanation is found in the size of the systems. For heat pumps, 85% of the units have an output of less than 20 kW, while gas and oil dominate in the larger categories. Therein lies a challenge.
This challenge is approached politically. The Swiss energy policy aims at phasing out nuclear energy and reduce greenhouse gas emissions. In August 2019, the Federal Council decided to reduce Switzerland’s net carbon emissions to zero by 2050. And this should be done while maintaining security of supply at affordable costs. One way forward is replacing of outdated heating systems when a building is renovated. It is foreseen that around 900,000 fossil-fueled heating systems will need to be overhauled or replaced by 2050, so the potential is huge.
The Swiss cantons have an important role, as they are responsible for building regulations. They have developed a common template for energy legislation, pointing out heat pumps as a preferred solution for heat generation. As this is not mandatory to implement, it will not necessarily come into force in all cantons, and a revised energy law is already rejected in some. But it is also implemented in some, and hopefully more will follow.
Stephan Renz, Switzerland