As of my last update in October 2023, Spain has several companies involved in nuclear power generation. The main players in this sector include: 1. **Endesa**: A major electric utility company in Spain, Endesa operates several nuclear power plants and is one of the largest energy producers in the country. 2. **Iberdrola**: Another leading energy provider in Spain, Iberdrola is involved in the generation and distribution of electricity, including from nuclear sources.