Heat pumps: energy from the environment

Heat pumps as efficient heating systems are currently extremely popular in Switzerland. But what should you be aware of when shopping for one? The following tips give even laypeople good guidance.

Oil prices sometimes go down, but then they go right back up. The risks and uncertainties in energy supplies and global climate change give us pause to think. Anyone who today builds a new house or renovates one thus frequently looks for alternatives to conventional sources of energy. Heat pumps have become very popular, and their market share has increased considerably in the last few years. According to the trade group Fachvereinigung Wärmepumpen Schweiz (FWS, Swiss Professional Association for Heat Pumps) roughly 20,000 heat pumps are purchased each year in Switzerland. «For newly constructed single-family homes the market share is already at from 80 to 85 per cent», notes Peter Egli, Head of the Seal of Quality at the FWS. Available on the market, as before, are «Swiss made» products and brands such as the heat pumps from the Swiss manufacturers CTA and Termogamma.

Luft-Wärme-Pumpe

The air-source heat pump: it absorbs thermal energy from the outside air (photo: FWS).

Heat pumps are becoming more affordable

Because of international competition, many heat pumps today come from abroad, whether the EU or increasingly from Asia. Further, heat pump prices are trending downwards thanks to technical advances, larger production volumes and competition. Basically you can distinguish between two types. Air-source heat pumps, which are quite cost-effective, take thermal energy from the outdoors and make it useable for home heating and domestic hot water. «For a mid-sized single-family home, such a heat pump costs roughly CHF 20,000 to 25,000», explains Egli. These systems, though, are not totally optimal when it comes to energy efficiency, especially when they are to generate heat on cold winter days.

The earth as a source of thermal energy

Brine/water heat pumps are more efficient but also more expensive. They draw thermal energy from the ground at a depth of approximately 50 to 300 metres. For a single-family home, drilling the borehole involves additional costs of near CHF 10,000. However, what you invest at the beginning is saved over the long term by lower operating costs. The best approach is to get information from your Cantonal Environmental Agency to see if drilling a borehole would be possible at a specific location. The different types of heat pumps make sense for both new construction as well as for renovations. There are systems of various sizes, whether for individual residences, for larger buildings or entire housing estates.

Once a heat pump is installed, it needs only a minimum amount of monitoring and maintenance (photo: FWS).

Once a heat pump is installed, it needs only a minimum amount of monitoring and maintenance (photo: FWS).

Good planning is the key

Fundamental planning and professional installation are particularly important. «Planning, layout and assembly place high demands on those involved in the planning stage», comments Egli. The entire system should be dimensioned and laid out to suit the needs of a specific building. It would a poor choice, for example, to plan a relatively high-capacity system for a poorly insulated house. The better approach is to first retrofit the building (meaning facades and windows), add better insulation and only then start thinking about switching over to a modern heat pump.

Heat pumps: practical tips

When it comes to the technical aspects, though, especially private owners and condominium associations are soon in way over their heads. There are various possibilities for getting assistance or protecting yourself with seals of quality and certificates.

  • Most cantons and communities offer energy information offices where you can consult experts at no obligation.
  • The Swiss Professional Association for Heat Pumps (FWS) conducts tests on units as well as examines drilling companies and issues them a seal of quality. www.fws.ch
  • Further, this trade association, in collaboration with Energie Schweiz and other partners, has created a new heat pump system design module (www.wp-systemmodul.ch). This service will also be available for smaller system throughout Switzerland at the latest from spring of 2015.

With certification of a design module, it is assured that the individual components of the heat pump system are properly planned and matched up to each other. Proper planning, layout and commissioning ensure energy-efficient operation.

Conclusion: After one or two winter seasons, check to see what the remaining energy needed to operate the heat pump is. If everything is running optimally, the investment will pay off for both the environment and your pocketbook.