Safeguarding environmental well-being has become a core agenda worldwide. In this regard, phasing out dependency on unclean fossil fuels and adopting cleaner energy alternatives is recognised as a prioritised energy policy reform. Therefore, this study investigates the dynamic impacts of renewable and nuclear energy uses on the ecological footprint figures of the G7 countries. The overall results reveal that enhancing renewable energy consumption and renewable electricity production are effective in reducing ecological footprints. However, simply increasing the nuclear energy consumption and electricity production levels are not enough to curb the ecological footprints. Rather, it is essential to scale the shares of nuclear energy in total final energy consumption and electricity output levels of the G7 nations. Thus, these key findings collectively portray the relevance of undergoing a clean energy transition in tackling environmental adversities in these developed countries. Moreover, the results verify the Environmental Kuznets Curve hypothesis while international trade is evidenced to further reduce ecological footprints.