Due to varied global challenges, potential energy solutions are needed to reduce environmental impact and improve sustainability. Many of the renewable energy resources are of limited applicability due to their reliability, quality, quantity, and density. Thus, the need remains for additional sustainable and reliable energy sources that are sufficient for large-scale energy supply to complement and/or back up renewable energy sources. Nuclear energy has the potential to contribute a significant share of energy supply with very limited impacts to global climate change. Hydrogen production via thermochemical water decomposition is a potential process for direct utilization of nuclear thermal energy. Nuclear hydrogen and power systems can complement renewable energy sources by enabling them to meet a larger extent of global energy demand by providing energy when the wind does not blow, the sun does not shine, and geothermal and hydropower energies are not available. Thermochemical water splitting with a copper–chlorine (Cu–Cl) cycle could be linked with nuclear and selected renewable energy sources to decompose water into its constituents, oxygen and hydrogen, through intermediate copper and chlorine compounds. In this study, we present an integrated system approach to couple nuclear and renewable energy systems for hydrogen production. In this regard, nuclear and renewable energy systems are reviewed to establish some appropriate integrated system options for hydrogen production by a thermochemical cycle such as Cu–Cl cycle. Several possible applications involving nuclear independent and nuclear assisted renewable hydrogen production are proposed and discussed. Some of the considered options include storage of hydrogen and its conversion to electricity by fuel cells when needed.