For the first time in history, Saaremaa is powered by cable

For the first time in history, Saaremaa is powered by cable

In November 2018, AS Connecto Eesti, AS Merko Infra and Elering AS signed construction contracts for the construction of new submarine electricity cables between the mainland and Muhumaa and between Muhumaa and Saaremaa. On October 2, 2019, we tensioned the submarine cable between Muhu-Orissaare in the Small Strait, which increases the security of electricity supply in Saaremaa and Hiiumaa. The entire project was completed one year earlier than the deadline indicated in the contract.

During the project, we installed 1230 m underground cable in Orissaare and 760 m in Muhu and  4670 m submarine cable. In the sea, the cable had to be laid in a pre-dug trench at a depth of 1.5 m. The excavation was carried out with special floating excavators. The works were complicated by the fact that the water level in the Small Strait is only about 40 cm in some places and in the deepest place it is about 3.8 m. This meant that the installation could not be done directly from the ship and the entire section of the submarine cable had to be floated to its location on pillows. The cable weighed a total of 308 tons (66kg / m). Also, the submarine cable is unique in the Estonian sense, as there are three 110kV phase and a 48-fiber optic cable combined in one cable.

The project once again highlighted Connecto’s strength in the services we can provide to our clients. While the excavation equipment, marine transport and submarine cable installation were purchased as a service from subcontractors, we did the rest of the work using our own resources: underground cable route preparation together with cable pulling, directional drilling, overhead line work in the mast and in substation, optical works, geodesy and design, laboratory and audit.

Meelis Uudmäe, Project Manager