Since purchasing the transmission infrastructure in the Canary Islands at the end of 2010, Red Eléctrica de España, Spain’s transmission system operator (TSO), has been undertaking an ambitious plan to update and improve it, under the name Project MAR (Improvement of Network Assets).
The project MAR has a budget of €150 million, of which €72 million has been spent so far, accounting for just over half of the proposed actions, while a further €33 million has been spent on maintenance activities for the Islands.
Project MAR to upgrade and integrate assets
The MAR project is aimed to adapt the electricity transmission infrastructure in the Canary Islands to the quality standards of Red Eléctrica’s facilities on the Spanish peninsula, including resolving existing deficiencies in this infrastructure, and to integrate these assets into the company’s control systems, in order to ensure the security of electricity supply in the archipelago.
According to Red Eléctrica, the project has already recorded a significant reduction in service interruptions, both in terms of energy and average outage time, reflecting improvement in the security and quality of supply.
The project will run to 2017 (extended from the previously planned 2015), given the particular conditions on the islands. The lack of a well meshed transmission grid implies that some actions need to be performed under live conditions but others with the facility out of service. Moreover, some of the proposed work is conditional on administrative permitting processes that may extend the forecast deadlines.
Achievements of Project Mar in 2014
During 2014 in Lanzarote 10 towers of the Mácher-Playa Blanca 66kV line were replaced and the insulator strings were replaced with others that better respond to the environmental characteristics and climate condition of the Canary Islands. These actions were especially complex due to fact that the work can only be carried out under live conditions given the current configuration of the electricity system in Lanzarote. Since the beginning of the project 70 towers have now been replaced in Lanzarote, out of the total of 112 that make up the transmission grid of the island.
In Fuerteventura, 42 towers were replaced: two in the Corralejo-Playa Blanca line, 22 in the Salinas-Gran Tarajal line and 18 in the Gran Tarajal-Matas Blancas line. In addition, the insulators have been replaced.
With regard to Gran Canaria, 11 towers were replaced, six of which are shared by the Jinámar-Telde and Marzagán-Cinsa lines and another five at the exit of the Jinámar thermal power station, the latter shared by the Jinámar-Telde and Jinámar-Marzagán circuits. In this action, the conductor cables and the insulators were also replaced.
One of the noteworthy actions of 2014 was the work carried out on the island of La Palma involving the integration and renovation of protective elements of the Guinchos-Valle 66kV line, and that of a coupling bay in the Guinchos substation.
On the island of Tenerife, three towers were replaced at the exit point of the Granadilla power station which shares the Granadilla-Chayofa and Granadilla-Los Olivos 66kV circuits, and the conductor cables and the insulators of the two circuits were also replaced. In addition, a total of 930 insulators have been replaced in the Candelaria-Tagoro, Cuesta de la Villa-Tacoronte, Guajara-Dique del Este and Manuel Cruz-Dique del Este lines.
Control system integration of assets
For the integration of assets into the control systems, Red Eléctrica is installing optical fibre in the Canary Islands’ grid.
For a 14 km length of the Cuesta Villa-Icod 1 line an innovative system had to be implemented, as the structural design of the towers makes it impossible to incorporate the grounding wire in which optical fibre is usually installed. In this case the conductor cable of one of the circuit phases has been replaced with a new one, named OPPC (OPtical Phase Conductor), which has the optical fibre integrated. The new conductor can simultaneously transport electrical energy and allow the substations to communicate with each other and with the control centres. This solution has the main advantage of not increasing the mechanical load of the line.
Other works included in Project MAR include the cleaning up of the safety corridors for the lines, repair and improvement of accesses to the towers, installation of transmission line identification markers, and the placement and adaptation of protective measures to prevent access to frequented towers.