Heat pump technology is considered an important pillar of the sector coupling, in which - amongst other - electricity generation and heat supply shall be integrated on the path towards a climate neutral energy future. It offers both a great opportunity and a challenge for manufacturers and engineers such as MAN Energy Solutions and ILF Consulting Engineers.

In the construction of gas pipeline systems, hermetically-sealed, electrically-driven high-speed compressors with magnetic bearings have already become indispensable. These High-Speed Oil-Free Integrated Motor compressor technology (HOFIM®) of MAN Energy Solutions have a power rating of up to 18 MW. The HOFIM® is a very compact skid based machine with the particular property to be emission-free and be able to react very quickly to load changes. The HOFIM® has initially been developed for mid/upstream and subsea applications for natural gas facilities with an extremely reliable and robust machine design.    

The core element of a heat pump system are reliable compressors, preferably with a compact design and the property to react quickly to load changes, the latter particularly in case wind power is used as source for electricity. For seawater based heat pump systems CO2 can be shown to be a particularly suitable refrigerant. The gas is changing its physical state from liquid to gaseous/ supercritical at temperature and pressure levels which are close to the design data of the technology developed originally for pipeline transport systems.

The use and application of this compressor technology allows for designing heat pump units with a significantly higher capacity than what is currently common in the industry. Within the paper a pilot project will be presented for an application in Northern Europe, where ILF has been supporting MAN Energy on design, construction and commissioning of a 50 MWth heat pump facility.