Red Eléctrica, the Redeia company responsible for the operation and transmission of the Spanish national electricity system, has entered the laying phase of the new submarine link between the islands of Tenerife and La Gomera. This interconnection will be crucial to ensure the security of electricity supply in La Gomera, enable greater integration of renewable energies, and achieve a reduction in overall electricity generation costs by connecting the systems on both islands.

The Cable Enterprise, one of world-leading Prysmian's most advanced cable-laying ships, has departed from La Gomera to begin installing the new 66-kV double-circuit submarine line between La Gomera and Tenerife, connecting the new substations of El Palmar, in La Gomera, and Chío, in Tenerife.

The one-month project begins with the laying of the first 66 kV circuit from La Gomera to Punta Blanca, the interconnection point with Tenerife. The Cable Enterprise will then return to La Gomera to install the second circuit, aiming to completing the project by early October and completing the entire link by year's end. 

The double-circuit 66 kV underground-submarine transmission line, with a capacity of 50 MVA per circuit, spans around 36 km underwater at a maximum depth of 1,145 meters and features two onshore segments in La Gomera and Tenerife.

The submarine interconnection between Tenerife and La Gomera, set to be commissioned by the end of the year, is part of the 2021–2026 Electricity Transmission Grid Development Plan. It includes the underground-submarine line, as well as two new substations: El Palmar in La Gomera and Chío in Tenerife. The first substation has recently been completed, while the Chío substation has been operational since the beginning of this year. 

The project involves the world's deepest three-phase 66-kV AC submarine link, necessitating a specially adapted cable design. It has been reinforced with lightweight materials capable of withstanding the demanding conditions of the installation. 

Furthermore, due to its length and complexity, bringing the cable onto both islands has presented a challenge in safeguarding the biodiversity in shallow waters, given the unique and highly heterogeneous volcanic soils. To overcome this challenge, directional drilling was used, which involves threading the underwater cable through a micro-tunnel that extends hundreds of metres from the coast, thereby avoiding any impact on the local marine life in the coastal area drilled. 

The route of the interconnection has been carefully planned to minimise its visual impact and to maximise the protection of the local vegetation and fauna in the different areas along the corridor.