The Seawater Chamber
at Ofelia Plads


Kvæsthusbroen 1, by Ofelia Plads, 1250 Copenhagen


Saturday 10-14


  • Hoist / ramp / level access to the front door
  • Level access in the building / site (no stairs)
  • Level access to outdoor areas
  • Lift
  • Accessible restroom
  • Locked doors can be opened from the outside in case of emergency
  • Chairs or benches to rest on
  • Possible to eat / drink
  • Disabled parking
  • Teleloop
  • Member of Solsikkesnoren
  • Member of God adgang

You’ve probably walked along Ofelia Plads when visiting the Royal Danish Playhouse or enjoying a drink on the square on a hot summer day. But did you know that hidden below the grooved concrete slabs, there is a secret seawater chamber?

You probably haven’t noticed. But in the grilled concrete slabs that cover Ofelia Plads, there is a hatch. And down that hatch, 15 meters underground, lies HOFOR’s seawater chamber. Admire the Royal Danish Playhouse and enjoy the harbor view before climbing down the stairs leading to an underground cooling plant in the heart of Copenhagen.

District Cooling at Ofelia Plads

District cooling basically works the same way as district heating, with production taking place at centralized cooling plants. Cold water is piped out to customers, who use it to cool the water in their own systems. The water is then returned to the central plant, where it is cooled down again. The district cooling system is an alternative to classic air conditioning systems.

The seawater chamber at Ofelia Plads was designed by Gottlieb Paludan Architects and comprises three chambers: two are filled to the top with water, while the third contains the pipes and pumps required to run the system.

A Giant Underground Refrigerator

Come to Open House in the heart of Copenhagen and learn all about a system that uses seawater to provide cooling to museums, businesses and institutions. Experience the network of underground pipes in the 202-square-meter, 10-meter-high seawater chamber and find out how cold seawater can act as a giant refrigerator for district cooling customers.