IBERDROLA invested €550 million in extending and improving its electricity grid in Spain in 2009. More specifically, the company has commissioned 22 new electricity substations, increased the capacity of another 78 facilities and constructed almost 3,000 km of low, medium and high voltage lines and approximately 3,200 transformation centres.

The construction of these new installations, together with the upgrade of some existing facilities, enabled IBERDROLA to add around 3,300 megavolt amperes (MVA) to the system last year, thereby increasing its installed capacity by 5.5%.

IBERDROLA has constructed five new substations in the Valencia region, totalling a capacity of 290 MVA. These facilities include Morvedre (100 MVA), in Valencia, and Oropesa (40 MVA), in Castellón. Almost 877 transformation centres and some 700 km of power lines have also been commissioned in this region.

A total of 477 MVA has been added in Castile-León due to the five new substations, the 408 transformation centres and 450 km of power lines developed. The largest substations commissioned are the Ávila substation (206 MVA) and Las Arroyadas, in Valladolid (150 MVA).

The new facilities in the Madrid region, contributing 630 MVA, include four substations, almost 430 transformation centres and 475 km of power lines. These infrastructures include the Ventas de Alcorcón and Mirasierra substations, both with 200 MVA.

In Castile-La Mancha, the company has commissioned three substations totalling 615 MVA, which include Fuentes de la Alcarria (450 MVA) in Guadalajara. They have also incorporated 450 transformation centres and 420 km of lines.

In Navarre, three substations contributing 100 MVA to the system, 84 transformation centres and almost 120 km of power lines have been built. The new facilities include the Imarcoaín substation, with a capacity of 50 MVA.

In the Basque Country and La Rioja, IBERDROLA has added a total of 85 MVA with a new substation in each region, as well as 215 and 131 transformation centres, respectively. A total of 145 km of lines were built in the Basque Country, while in La Rioja the lines was extended by 64 km.

Finally, in Extremadura and the Murcia Region, IBERDROLA has constructed 121 and 487 transformation centres and has extended the power lines by 146 and 476 km, respectively.

Key facilities for the system

The purpose of electricity substations is to transform energy from   high to medium voltage before it reaches the consumer. This energy is then distributed to the transformer stations that directly supply homes. The power lines transmit and distribute the energy from the different facilities, connecting them to one another to form an extensive distribution grid.

They play a key role in the electricity system and continued investment is required to create a major distribution grid to meet rising demand and enhance supply quality.