The submarine cables under Suur and Väike Väin straits are most essential for the electricity supply stability of Saaremaa and Hiiumaa islands. In Suur Väin strait, we replaced two old 35 kV cable lines between Rõuste substation on the mainland and Tusti substation on Muhu island with a new 110 kV submarine cable. The total length of the Suur Väin strait cable is nearly 11 kilometres, 9.7 km of which is the submarine cable. The total mass of the cable placed into the sea by a special ship was ca 650 tons. In addition, a new 110 kV compartment was built for connecting the Rõuste substation line, and after the submarine cable was energised, the old 35 kV cable lines were dismantled and disposed of.

In Väike Väin strait between Muhu and Saaremaa islands, we laid a new 110 kV submarine cable, which makes the connection to Saaremaa and Hiiumaa islands less dependent on the Väike Väin strait overhead lines and the weather. The total length of the Väike Väin strait cable line from Muhu island to Orissaare substation is 6.7 kilometres, 4.7 kilometres of which is the submarine cable.

The current carrying capacity of the cable under both straits is 520 amperes. The diameter of the submarine cable is 190 millimetres and a metre of it weighs 67 kilograms. The cables produced in their total length without joints were dug into the sea bottom to avoid damage by anchors, ridged ice and other external factors. A fibre optic communication cable was also placed into the sea together with the new cables.

On 1 July 2021, Merko Ehitus Eesti acquired a stake in Connecto Eesti, and the Merko electrical construction business line merged with Connecto. Acting jointly under the Connecto brand makes it possible for us to offer a significantly broader range of services – in addition to the design, construction and maintenance of low, medium and high voltage electricity networks, Connecto also operates in the field of telecommunications and gas networks.

View the works performed by Connecto.