Heat from groundwater heats the Champagne district of Biel

Heat from groundwater

Safe, clean energy for heating and hot water: In the Champagne district of Biel, the Champagne heating network has supplied heat from renewable energy since May 2018. Two customised heat pumps from the Swiss cooling and heating specialist CTA are at the heart of the system. They use groundwater as a natural, environmentally friendly heat source.

The first consumers—the high-rise building of the city of Biel pension fund, the Champagne school building, and cooperative residential buildings—have been supplied with heat since October 2017.

Four speed-regulated reciprocating compressors

The fact that an entire district can be supplied with heat from groundwater demonstrates the dimensions of the heat pumps. Both units weight around five tonnes each and, with their four speed-regulated reciprocating compressors, supply 650 kW of heating output per unit. The heat comes from the groundwater, which is extracted at a temperature of between 10 and 12°C and cooled by the heat pumps to 4°C.

Sustainable, state-of-the-art solution

The entire system complies with modern, technical standards. The hydrofluroolefin (HFO) refrigerant is used. At the same time, the heating plant meets all the corresponding safety requirements. And, most importantly: the groundwater is transferred to the heat pump via an intermediate circuit. In doing so, the heating network ensures that the sensitive groundwater will never come into direct contact with the refrigerant.

A flagship project

In many respects, the Champagne heating network is a flagship project. The heat pumps are highly (energy-)efficient. Additionally, thanks to the natural heat source, 620 tonnes of CO2 can be saved per year compared to a fossil-fuel heating system. And, consumers have the certainty of knowing that the heat comes from a renewable energy source directly within their region.