Expansion
In 1970, Iberduero, together with its subsidiaries, already produced 27% of the electrical energy consumed in Spain. Its subsidiaries were Electra Aguera, Electra de Burgos, Electra de Extremadura, Electra Popular Vallisoletana, Electra de Salamanca, Electra de Soria, Electra de Logroño, Compañía Eléctrica del Urumea, Fuerzas Eléctricas de Navarra, El Irati, León Industrial, Vitoriana de Electricidad and Saltos del Sil. In addition, it was part of Nuclenor (operation of nuclear power plants) and Terminor (operation of thermal power stations), both shared 50/50 with Electra de Viesgo.[2] Iberduero developed a large hydroelectric system, with more than 100 plants, being especially important the one formed by the plants located on the Douro and its tributaries, which included the Aldeadávila, Saucelle, Almendra, Castro, Ricobayo and Villalcampo dams.[5]
Iberduero's thermoelectric program began in the 1960s. In 1965 it started up the expansion of the Burceña thermal power plant in Barakaldo, in 1968 the Pasajes thermal power plant and in 1969 the Santurce power plant. As part of Terminor, it started up the Velilla power plant in 1964, although in 1984 it bought its part from Electra de Viesgo and built a second group.[6]
It also participated in the generation of electricity from nuclear energy. To this end, it also formed a 50/50 alliance with Electra de Viesgo in the creation of Nuclenor in 1957, which carried out the construction and start-up of the Garoña nuclear power plant in 1971. Iberduero also undertook the construction of the Lemóniz nuclear power plant, which was paralyzed in 1982 when it became the target of the terrorist organization ETA, which attacked its facilities and murdered two of its engineers (José María Ryan and Ángel Pascual Múgica) and three workers.[7][6] In 1985, it became the sole shareholder in the Almaraz nuclear power plant (53%) and in the Trillo nuclear power plant (51%).[6]
All these structures led to frequent capital increases by the company, which was listed on the Madrid Stock Exchange and the IBEX 35.
The number of subscribers to the company increased from 250,000 at the time of its foundation to 1,400,000 in 1967. The company's largest shareholder since its foundation has been BBVA (Banco Bilbao Vizcaya since 1988).
