Submarine Power Cables

Submarine Power Cables are used to carry power underwater.  They are used to connect small islands with the mainland.  Sometimes, the route through the water is shorter than through land.  Submarine Cables are used for both AC as well as DC transmission. 

AC is used up to 80 km while DC is used for long distance transmission.  Submarine cables are mostly gas filled cables.  The cable laying is done by special ships.  XLPE cables fpr submarine transmission are also available.

AC cables can be laid as three separate cables or as a single 3 phase cable.

Offshore wind farms are connected to the mainland by submarine cables.   

Damage to these cables by shipping is a matter of concern.  The routes which contain submarine cables are specially marked in nautical maps.