Investigations start for faulty SKAGERRAK-4
Since February 2019, there have been three faults on the
Skagerrak 4 (SK4) interconnector,
an electricity connection between Danish and Norwegian national grids.
The faults occurred on February 6, July 21 and October 9, respectively,
causing a complete connection closure for several weeks.
The faults have been found in the onshore cable in Denmark. To find the
causes of the three faults, Energinet and the cable supplier will now dig
down to the cable in several places on the route and take samples. The
cable is cut and pieces are examined by Energinet, the cable supplier and
by experts from an independent company.
Work on sampling
begins on May 25 and ends on July 28, which is why the SK4
connection during that time has been shut down and taken out of service.
"We cannot determine today how the errors occurred, but we agree with
the cable supplier to have a thorough analysis and get expert opinions.
Only when we have the conclusions do we decide what is needed, but it is
important to state that the SK4 connection must be back in full capacity
operation, so that there is full opportunity for trade and export and import
between the two countries," emphasised director of Energinet Electric
Transmission Henrik Riis.
In order to minimise the risk of further faults, the capacity of Skagerrak
connections has been reduced from 1700 to 1387 MW since October. The technical
solution chosen for Skagerrak
that capacity in any given situation is generally asymmetric, allowing
for loads of 1387 MW in the primary direction and 950 MW in the secondary
direction. Currently, the direction Norway towards Denmark is the primary
direction. However, in future it might be possible to increase capacity
to 1350 MW in secondary direction.
For more information on interconnector projects worldwide,