The cable-laying vessel Cable Enterprise, one of the most modern ships in Prysmian’s fleet, began operations yesterday at the rear of the port of San Sebastián de La Gomera for the installation of a submarine cable that will connect the electrical systems of La Gomera and Tenerife.
This operation marks a significant milestone in the electrical interconnection project, which is expected to be completed by the end of this year, as stated by the Cabildo. The interconnection will be crucial for ensuring supply security in La Gomera, enabling greater integration of renewable energies and achieving a reduction in overall generation costs by connecting the systems of both islands, according to Red Eléctrica.
It is worth noting that this vessel docked last week at the port of Granadilla in southern Tenerife to finalise preparations for the underwater cable laying work.
The commencement of these works represents the final phase of an infrastructure project led by Red Eléctrica, in coordination with the Spanish Government, the Government of the Canary Islands, the Cabildo of La Gomera, the Cabildo of Tenerife, involved local councils, and the Port Authority of Santa Cruz de Tenerife.
The president of the Cabildo of La Gomera, Casimiro Curbelo, highlighted the significance of this moment for the island, stating that “we are taking a decisive step for the energy future of the insular territory.” He emphasised that the beginning of the submarine cable laying signifies the realisation of “years of effort, dialogue, and cooperation between administrations, along with Red Eléctrica, to ensure citizens have access to safer, cleaner, and more stable energy.”
Curbelo also underscored that this interconnection will enable the island to “progress towards a more sustainable model, capable of integrating the full renewable potential we possess, reducing dependence on fossil fuels and opening the possibility of even supplying surpluses to Tenerife.”
The island leader insisted that this project “is an example of how, by working together, administrations and public initiatives can bring about infrastructure that transforms the present and future of a territory.”
Submarine Cable Works
The laying of the new dual electric submarine circuit between La Gomera and Tenerife will connect the new substations at El Palmar, recently completed on the island, and Chío in Tenerife.
According to Red Eléctrica, the works will last for a month, beginning with the installation of the first 66kV circuit from La Gomera to Punta Blanca, the interconnection point with Tenerife. Subsequently, Cable Enterprise will return to La Gomera to lay the second circuit, aiming to complete all works by early October, with the goal of finishing the entire link by the end of the year.
This underground-submarine dual circuit line at 66 kV, with a transport capacity of 50 MVA per circuit, includes a submarine section of approximately 36 kilometres in length, running at a maximum depth of 1,145 metres, as well as two land sections on La Gomera and Tenerife.
Specifically, this is noted to be the world’s deepest three-pole submarine connection at 66 kV, which necessitated a specially adapted cable design reinforced with lightweight materials capable of withstanding the demanding conditions of its installation environment.
Moreover, due to its length and complexity, the arrival of the cable on land at both islands presents a challenge to ensuring the protection of biodiversity in the shallower waters, given the unique nature of the highly heterogeneous volcanic soils. To address this, directed drilling techniques have been employed, allowing the cable to enter the sea through a microtunnel that emerges hundreds of metres from the coast, minimising any impact on the biological communities along the drilling stretch of the coast.
Additionally, it was reported that the route of the interconnection has been designed to minimise landscape impact and ensure maximum protection for vegetation and fauna in the areas it traverses.
The submarine interconnection between Tenerife and La Gomera, set to be operational by the end of the year, is included in the 2021-2026 Electric Power Transmission Network Development Plan and comprises the underground-submarine electrical line and two new substations, El Palmar in La Gomera and Chío in Tenerife.
