This paper constructs the returns and volatility system networks of the global new energy companies using the connectedness network approach. Then, it measures the information spillover direction and degree among the global new energy companies for the two systems, furthermore, exploring the rolling-windows estimating method to investigate the time-varying characteristics of the information spillover mechanism. It selects 20 large energy companies with a weighting greater than 1.24% from the NEX index and obtains the weekly stock prices for these companies from November 24, 2006 to January 4, 2019. Some new findings can be obtained: (1) The total information spillover degree among the global new energy companies is very high, especially for the volatility system. (2) The static and dynamic asymmetry indexes confirm the existence of asymmetric effect for the information transmission mechanism, which shows that the bad news does contribute more to the systemic risk of global new energy company stock market than the good news. (3) Some new energy companies act as net information transmitters, which are relatively important in the networks. These new findings could provide a reference for investors in the new energy sector to develop specific portfolios and risk management, as well as advise relevant policy makers.

本文采用连通网络法构建了全球新能源公司的收益与波动系统网络。然后，它测量了这两个系统在全球新能源公司之间的信息溢出方向和程度，并探索了滚动窗口估计方法以研究信息溢出机制的时变特征。它从NEX指数中选择了权重大于1.24％的20家大型能源公司，并获得了这些公司从2006年11月24日到2019年1月4日的每周股价。可以获得一些新发现：（1）总信息全球新能源公司之间的溢出程度非常高，尤其是在波动性系统方面。（2）静态和动态不对称指标证实了信息传递机制的不对称效应的存在，这表明坏消息确实比好消息对全球新能源公司股票市场的系统风险的影响更大。（3）一些新能源公司充当网络信息发送者，在网络中相对重要。这些新发现可以为新能源行业的投资者开发特定的投资组合和风险管理提供参考，并为相关政策制定者提供建议。