Utilizing Fourier autoregressive distributed lag and Fourier Toda–Yamamoto causality methodologies, this research assesses the effects that renewable energy consumption and environmental policy had on the economic sustainability of China from 1991 to 2022. Our findings highlight the positive impacts of renewable energy use and stringent environmental policies on China’s economic growth, while also pinpointing the supportive roles played by foreign direct investment, trade openness, and financial sector evolution in fostering a sustainable economic environment. Conversely, a reliance on fossil fuels emerges as a significant barrier to sustainability. Causality tests confirm the essential roles of renewable energy and environmental policies in advancing China’s economic sustainability. This study underscores the critical need for integrating sustainable energy and environmental strategies within China’s economic development framework, advocating for a holistic policy approach that balances economic growth with environmental conservation. This research underscores the imperative for a sustainability-centered strategy for China’s economic advancement.