Yes, aluminum can be used in nuclear power plants, but its application is limited due to its reactivity with neutrons. Aluminum is used in non-nuclear grade components such as cooling systems, electrical equipment, and structural supports. However, it is not used in the core or in high-radiation areas due to its tendency to absorb neutrons, which can lead to transmutation and the production of radioactive isotopes. Materials like stainless steel, zirconium alloys, and other neutron-resistant materials are preferred for core components and high-radiation environments.