Water is essential for almost all energy processes. This paper analyses the evolution of the cooling water needs of thermal power plants in the Ebro River basin, the largest contributor to the Spanish electricity grid, over the period 1969–2015. It makes several contributions. First, the cooling water needs for the plants are estimated. Second, these water requirements are compared to other water-using activities in the region. Third, a long-term water-use efficiency analysis is carried out. Finally, water-saving measures are proposed to counter possible future water scarcities. The results show that thermoelectric water consumption per capita is around 7 m³/year. Estimated future thermal power generation water withdrawals (around 500 m³ per capita/year) might compromise flows for other water uses in periods of drought.

This paper focuses on the fact that the water–energy nexus remains an irrelevant issue on the energy policy agenda and on the priorities of the energy leaders in Spain. This is a striking fact given that this takes place in the most arid country in Europe, where almost two-thirds of electricity generation would have to be halted in the absence of an adequate water supply. We contend that part of the explanation may lie in the lack of official statistics and inconsistent sources of information on the water–energy nexus in Spain. To illustrate this point, we provide examples of the uneven data available for one of the most intensive freshwater users in the thermoelectric sector in Spain: nuclear power plants. Our research demonstrates the need for improved indicators as policy instruments in the water–energy nexus in Spain since it is impossible to improve what cannot be measured.

Today, human activities are highly dependent on fossil fuels and industrialized forms of agriculture and have reached a level that could damage the Earth’s systems

Water resources are limited and uneven in space and time. Competition for the use of the resource can lead to conflicts between water users. Besides its use for irrigation and agriculture, water is an essential input in the thermoelectric power generation process. Massive Spanish nuclear program projects have conditioned water management in the country, as significant freshwater volumes need to be constantly available for the proper operation of these facilities. Water for cooling has conflicted with other water-using activities, resulting in regional imbalances. The present study shows that cooling water represented a source of conflict between irrigators and electricity companies in Spain in the 1970s and 1980s. A historical analysis of documentary sources reveals that the drawing off of fresh water for cooling by the nuclear industry was one of the many causes of frequent disputes and the rise of social movements against the installation of nuclear power plants in Spain during that period.