Every year, Red Eléctrica carries out a maintenance plan for its lines and substations with the object of maintaining their reliability and therefore guaranteeing the effective working of the transmission grid, avoiding and reducing the unavailability of the installations.

To define the maintenance works, periodic inspections are planned, not just for the lines but also for the substations, with the objective of verifying their actual state. Once the data is collated, actions to renovate and improve the assets are implemented.

Additionally, during the summer, and as a compliment to the annual maintenance plan, Red Eléctrica intensifies works to ensure the correct functioning of its installations which, being in the open, are more vulnerable to the heat.

In addition, as of January 2008, Red Eléctrica's Maintenance School gives courses to its transmission grid maintenance technicians, guaranteeing them fully up-to-date professional training and qualifications which ensures their installations are maintained to the highest possible standard.