Aalborg Forsyning boosts production capacity with district heat pumps

MAN Energy Solutions is collaborating with Bilfinger for mechanical system design and construction and ACS for electrical infrastructure design and implementation.

Danish multi-utility company Aalborg Forsyning has ordered an additional heat pump unit from MAN Energy Solutions, increasing the heating capacity to 177 MW with four units. The heat pumps, each with a capacity of around 44 MW, are the largest ever installed in a district heating plant worldwide. The plant will supply up to 700,000 MWh of heat annually.

The district heating plant, located on the northern bank of the Limfjord strait, will utilize seawater as its primary heat source. The heat pumps will utilize electricity from Aalborg Forsyning’s renewable sources to elevate the water temperature from 1-15° Celsius up to 98°, which is the temperature used in the district heating network. This project will reduce CO2 emissions by up to 210,000 tons annually compared to the city’s coal-fired power plant, scheduled for closure in 2028.

 Mikael Adler, Head of Sales and Project Management Heat Pumps at MAN Energy Solutions, said,  “This follow-up order from Aalborg Forsyning underscores their trust and confidence in our heat pump technology. We are excited to continue our collaboration on this pivotal project and are particularly pleased to support Aalborg on its path to net-zero. The integration of this fourth heat pump unit will further enhance the environmental benefits of the city’s district heating network.”

Jesper Høstgaard-Jensen, Technical Director at Aalborg Forsyning, said, “We are delighted to expand the overall heating capacity in collaboration with MAN Energy Solutions. These seawater heat pumps are the key part of our transition from coal-based to climate-friendly district heating, providing flexible heat at a very high temperature of up to 98°C. Additionally, it is a clear advantage that MAN’s technology uses a natural refrigerant, making it well-suited for heat-pump operation at such high district-heating temperature.”

MAN Energy Solutions is collaborating with Bilfinger for mechanical system design and construction, and ACS for electrical infrastructure design and implementation. This collaboration, along with MAN and Aalborg Forsyning’s cooperation, ensures seamless integration of the heat pump system into the project.

Heat pump technology uses electrical energy to increase low-temperature thermal energy, generating three MWth of usable thermal energy for every MWh of electricity invested. MAN’s solution uses toxicologically and environmentally safe CO2 as a refrigerant, enabling fast power-balancing of the electrical grid and supporting intermittent power generation like solar and wind.

Core elements of Aalborg’s future heat pump plant are four oil-free, hermetically-sealed HOFIM® motor-compressor units, which are manufactured and tested by MAN Energy Solutions in Zurich, Switzerland.

The compression unit utilises a high-speed motor and active magnetic bearings, enabling it to operate without the need for a dry gas seal system and a lube oil system. The scope of contract also encompasses a Long-Term Service Agreement with MAN PrimeServ, including PrimeServ Assist for real-time monitoring, data-analytics and diagnostics of the compressor technology.