The future need for critical raw materials associated with long-term energy and climate strategies: The illustrative case study of power generation in Spain

The deployment of renewable energy technologies, though necessary to decarbonise our society, poses a risk stemming from the massive increase in the use of critical raw materials. This work presents a prospective evaluation of a national electricity generation mix up to 2050 and discusses the increase in several critical and strategic materials used in this transition. Results indicate that the deployment of solar photovoltaics and wind energy will raise material criticality concerns in the coming decades. When comparing a decarbonisation scenario aligned with the 2030 Spanish policy with a business-as-usual scenario, results show that a higher penetration of renewables would involve increases of up to 53 % in silicon, 27 % in aluminium, 11 % in copper, and less than 1 % in other materials by 2050. Overall, the decarbonisation scenario would involve up to 12 % more materials. Furthermore, criticality indicators show increases of 0.06 % and 5 % by 2050 depending on the selected indicator. Differences in figures highlight discrepancies in the way criticality is evaluated, suggesting that further research is needed. Nevertheless, national long-term energy policies such as the Spanish one are urged to implement criticality issues in their formulation. Consequently, the authors recommend including critical material usage within energy and climate planning models.