Many years of development work lie behind the choice of gas compression on the seabed for Åsgard. We started testing the technology at the K-lab on Kårstø as early as 2008.

The compression process is necessary in order to increase the pressure before the gas can be sent in the pipeline to Åsgard B.

The solution consists of two gas compressors, each 10 MW. In addition, there will be a scrubber, pump and cooler. All of this will be placed in a gigantic structure measuring 70 x 40 x 20 metres and weighing 1500 tonnes. This will be installed on the seabed and tied in to the templates for the Mikkel and Midgard reservoirs.

The wellstream from the reservoirs contains some condensate which must be separated before the gas stream goes on to compression. This separation takes place by the gas being cooled down and the liquid separated.

The remaining gas is transported into the compressor at low pressure and will be gradually compressed through the compressor, finally flowing out at considerably higher pressure. The closer to the wellhead the compressor is placed, the better the effect will be. Through the compression process, the gas will absorb enough pressure to be transported on to the platform.

The compressor will receive power from Åsgard A. Because the compressors will be operated with electricity from Åsgard, there will be modification work on the Åsgard A and B platforms. On Åsgard A, for instance, a new module weighing 800 tonnes will be installed.

Initially, we will operate the two compressor trains in parallel, but towards the end of the field’s lifetime we can also operate the trains in a series.