<p>Governments worldwide have prioritized new energy as pivotal for green transformation. Listed new energy companies have attracted substantial investment, yet their interconnected stock prices induce complex and dynamic risk spillovers that pose challenges to risk management. This study employs a quantile connectedness approach coupled with rolling-window analysis to examine volatility spillover networks among China’s top 20 listed new energy companies. It uncovers asymmetric and time-varying characteristics. Systemic importance is also identified based on firms’ risk transmitting and receiving spillovers. The results demonstrate that connectedness is much stronger at extreme quantiles compared to the median, indicating amplified risk contagion during both extreme downturns and upturns. Notably, connectedness at the upper quantile exceeds that at the lower quantile, confirming an asymmetric mechanism. Furthermore, time-varying analysis reveals regime shifts in spillover dynamics, especially in the wake of major market shocks such as the COVID-19 pandemic and the 2022 Russia-Ukraine War. Additionally, the systemic importance of China’s new energy companies varies depending on spillover directions and market conditions. Interestingly, medium- and small-sized companies, despite their relatively smaller market capitalization, play crucial roles in volatility spillovers due to their high network connectedness. Besides, both financial characteristics and the macroeconomic environment emerge as significant drivers of spillover effects among new energy companies. These findings enhance the understanding of volatility transmission within the new energy market, offering valuable insights for diversified portfolios and policies to support sustainable development.</p>