For the fifth time, the European Heat Pump Association (EHPA) has awarded the internationally coveted prize of Heat Pump City of the Year. In 2015, BITZER’s customer Calefa Oy won the award for a project in Mäntsälä, Finland.

The aim of the project is to efficiently exploit the waste heat from a computing centre for district heating and to protect the environment. Heat exchangers first use the hot air extracted from the computing centre to heat water. In the next step, heat pumps in a district heating facility then raise the temperature of the water from 40 to 85°C. In this way, 75% of the energy originally used can be reused. This is not just very efficient, it also protects the environment. In the first phase, the CO emissions will be reduced by 4,000 metric tons per year and, when the project has been completed, this will be up to 11,000 metric tons of CO every year. Calefa’s role in this is to enable the entire technical conversion of waste heat into useful heat.

One special feature is that this is the first time when such a large amount of waste heat from a computing centre can be directly exploited for district heating. To increase the water temperature to 85°C, particularly powerful and efficient heat pumps are required. This process is supported by 24 six-cylinder ECOLINE compressors from BITZER at the heart of the heat pump system, which can each offer flow rates of up to 150 m3/h (at 50 Hz).