Abstract
The study is aimed at investigating the effects of nuclear fusion reactors, human development, and economic growth on nuclear energy consumption in the United States from 1990 to 2019 using time and frequency causality analyses. The time domain causality analysis examined the relationship between variables over time using a single test statistic, while the frequency domain analysis explored causality in the short and long term at different frequencies. The findings from the time domain analysis indicated that nuclear energy consumption had a unidirectional causal effect on the human development index. Conversely, nuclear fusion reactors had a unidirectional causal impact on nuclear energy consumption. The results from the frequency domain analysis revealed that economic growth had a permanent unidirectional causal effect on nuclear energy consumption. In contrast, nuclear energy consumption had a temporary unidirectional causal impact on the human development index. Additionally, there was a bidirectional temporary and permanent causal effect between nuclear fusion reactors and nuclear energy consumption. Based on these findings, the study recommends that the United States continue providing financial incentives to develop nuclear energy technologies, such as constructing new nuclear power plants and offering subsidies to encourage the use of nuclear energy.