Red Eléctrica commences the laying of the submarine interconnection cable between the Iberian Peninsula and the Balearic Island

Red Eléctrica has today begun laying the submarine cable for the electrical interconnection between the Iberian Peninsula and the Balearic Islands (the Romulo project). The ship Giulio Verne has started in the Santa Ponsa Bay (Mallorca) the installation of the first of three submarine cables of which the interconnection is comprised of. This task shall continue over the coming days on the high seas until the cable reaches Sagunto (Valencia), where it will be connected to the Spanish peninsular electricity system. 

This electrical connection will allow an improved quality of supply in Mallorca and will integrate the island into the Iberian electricity market, which will represent a cost saving for the whole Spanish electricity system. Additionally, it will guarantee the reliability of the supply in the face of the constant increase in consumption within the islands. 

The electricity link between the Peninsula and the Balearic Islands will consist of three cables, each one measuring 237 kilometres in length and reaching a maximum depth of 1,485 metres below sea level. The interconnection will operate in direct current, and as such it has been necessary to build a converter station at either end to convert it into alternating current, as this is what is used in the electricity systems on the Peninsula and Balearic Islands. 

In order to lay the cable, the Giulio Verne is equipped with a dynamic positioning system which allows it to follow the established route with precision and to remain perfectly stationary when sea conditions demand that work be halted. These devices are hugely important given that the laying of each of the three cables is carried out in one continuous length, that is to say, without the need to perform joints. 

At the start of the works for the installation of the circuit, the ship positions itself 500 metres off the coast and begins to release the cable, which is positioned on the sea bed with the aid of a remote controlled vehicle capable of performing minor adjustments. Once the opposite shore is reached, the remaining cable is released so that a team of scuba divers can lay it on the sea bed with the aid of floats and auxiliary vessels. 

After the laying of the three electrical cables and the fibre optic cable to guarantee communications, Red Eléctrica shall begin a period of tests prior to commissioning the line, planned for later this year. 

The Romulo Project has, at all times, sought to fully respect the environment. For this reason, at depths of less than 800 metres, the submarine cables will be protected below the sea bed in a trench one-metre deep. Additionally, in these areas the route of the cables and their protection system have been specially selected, so as to respect the meadows of Posidonia oceánica seagrass, a species of vegetation native to the Mediterranean and protected at a European level, to guarantee its conservation.