Years of development 1961-2000

The 1960s marked a turning point in the history of energy. Confidence in progress and technological capability was high. In this context, the development of nuclear energy represented an unprecedented leap forward. Companies on both sides of the Atlantic – including those that would later form Iberdrola – entered a new era driven by the pursuit of efficiency, security and sustainability in electricity generation.

The 1970s brought expansion and change. Rapid industrial and urban growth led to a surge in energy demand, prompting a search for new energy sources and a wave of corporate integration aimed at strengthening structures and securing supply.

However, the international landscape was shaken in 1973 by the oil crisis. Global energy dependence was exposed, and the electricity sector emerged as a key player in ensuring stability and enabling recovery.

In the years that followed, privatisation and liberalisation processes began to reshape the energy landscape. Major companies moved towards more open, competitive and interconnected models, laying the groundwork for the sector’s transformation into a truly global industry.

The 1990s coincided with the rise of globalisation, characterised by the integration of local economies into an international environment in which industrial production and capital flows operated on an intercontinental scale. At the same time, technological development accelerated, particularly in information and communication technologies with the expansion of the internet.

Large electricity companies, as central players in economic and social development, adapted to this shift and began to operate as true multinationals. During this period, business structures evolved into three core areas: energy generation, networks and supply. Operations increasingly took on an international dimension, reflecting broader market and societal trends.

In Spain, the Electricity Sector Law (Law 54/1997 of 27 November) liberalised the market for non-domestic customers. This step, taken in line with European directives, promoted competition in a strategic sector and introduced a more flexible regulatory framework.

In Spain, the energy sector continued to evolve through new alliances and the development of nuclear energy. In 1963, Iberduero acquired Saltos del Sil, which had agreements with central Spain distributors and Électricité de France.

The following year, the company inaugurated one of Spain’s most significant engineering achievements: the Aldeadávila hydroelectric plant, which became the largest in western Europe. Its commissioning acted as a major driver of economic growth in the 1960s and 1970s.

Shortly afterwards, in 1970, construction was completed on Spain’s tallest dam: Almendra, also known as the Villarino plant. At 202 metres high, it still holds this distinction more than 50 years later.

Nuclear energy gained prominence in the 1970s. In 1971, the Santa María de Garoña nuclear power plant began operations, becoming one of the first in Spain. A decade later, in 1981, the Almaraz nuclear power plant in Cáceres entered commercial operation as the country’s first second-generation facility. Four years later, the Cofrentes nuclear power plant in Valencia also began operating.

However, natural resources continued to represent an exceptional opportunity for energy generation in Spain and, in 1989, La Muela hydroelectric power plant in Valencia was connected to the grid.