The present state of the art in subsea power has been defined by the 310 meter-deep Åsgard field in Norwegian territorial waters. Here, the operator Statoil has just installed world’s first wet gas seabed compressor to increase pressure in the reservoir. It is estimated that it will extend the life of the Brent field by the equivalent of 306 million barrels of oil.
ABB was commissioned to provide power to the compression system, which it did by means of a cable that transmits 18 megavolt-amperes at 120 hertz over 43 kilometers. That sets a new world record for distance, voltage and frequency between a drive on a floating production facility and a seabed compressor, and points the way to what will be possible in the increasingly challenging future of subsea electrical engineering.
Åsgard is located on the Haltenbanken of Norway in water depths of 240-310m (787-1017ft). Gas and condensate from the Midgard and Mikkel reservoirs are transported through long distance flow lines to the Åsgar A platform.
ABB is responsible for system engineering including design, commissioning, qualification tests, measurement systems, simulations of topside drives, topside transformers and subsea transformers.
(Photo credit: Aker solutions)