MAN delivers another large heat pump to Aalborg

18.07.2024

The Danish city of Aalborg has commissioned MAN Energy Solutions with a fourth seawater heat pump. It will be part of a district heating plant that will replace a coal-fired power plant.

The Danish district heating supplier Aalborg Forsyning has placed a follow-up order with MAN Energy Solutions for a further heat pump unit, the manufacturer announced on July 17. This order follows the first from 2023 and increases the total heat output to 177 MW with a total of four units. Construction of the project is scheduled to begin in August 2024. After a test and commissioning phase, Aalborg Forsyning intends to take over the heat pump system in 2027.

The location of the district heating plant in Norbis Park on the northern shore of the Limfjord will enable the use of seawater as a heat source in the future. The heat pumps will use electricity from Aalborg Forsyning's renewable energy sources to raise the temperature of the seawater from 1 to 15 degrees Celsius up to 98 degrees Celsius, which corresponds to the temperature in the district heating network. The city plans to decommission the coal-fired power plant by 2028.

Each heat pump has an output of around 44 MW, making it one of the largest heat pumps installed in a district heating plant in the world, according to MAN. In total, the system will supply up to 700 million kWh of heat per year, which corresponds to a third of Aalborg's heat production.

The system can deliver heat at a very high temperature - up to 98 degrees, which is unique, says MAN. "Another advantage is that MAN Energy Solutions uses a natural refrigerant, which is ideal for heat pump operation at high district heating temperatures. In addition, fast regulation on the electricity side ensures that our profitability is optimized," says Jesper Hostgaard-Jensen, Technical Director at Aalborg Forsyning. In addition, the solution enables rapid balancing of the electrical grid output and thus supports the integration of renewable energies.

According to MAN, the core element of Aalborg's heat pump system consists of three motor-compressor units, which are manufactured and tested by MAN Energy Solutions in Zurich (Switzerland). The compressor units use high-speed motors and active magnetic bearings, allowing them to operate without a dry gas sealing system and oil system. MAN Energy Solutions is carrying out the project in collaboration with two partners: Bilfinger is responsible for the design and construction of the mechanical systems, while ACS is responsible for the design and implementation of the electrical infrastructure.

Author: Heidi Roider
Source: Energy & Management Powernews