China's green energy investment risks in countries along the Belt and Road

China's green energy investment in the countries along the "Belt and Road" (B&R) has been growing continuously, but investment failures are also increasing. Diplomatic risk, political risk, operational risk, ecological risk, resource risk and socioeconomic risk are the important influencing factors of overseas green energy investment, and even play a decisive role. However, few studies have made an overall assessment of green energy investment risks in the countries along B&R based on these influencing factors. Therefore, this paper first constructs a comprehensive evaluation index system, including 6 first-level indicators and 35 second-level indicators. Secondly, the three-scale method and the improved entropy-weight method are used to determine the weight of each index, and the VIKOR method is used to evaluate the risks of China's green energy investment in the 37 countries along B&R. Finally, K-means clustering is used to classify the investment risks into 4 levels from I to IV. The results show that three countries, namely Afghanistan, Montenegro and Maldives, have the highest risk, ranking at risk level I, two countries are at risk level II, 25 countries are at risk level III, and the other seven countries have the lowest level of risk, which are Laos, Saudi Arabia, Vietnam, Hungary, Mongolia, Malaysia and Singapore. Based on these results, we propose various investment risk management strategies for countries at different risk levels. Our results provide a reference for China's government and Chinese enterprises to mitigate overseas green energy investment risks, and provide policy suggestions for host countries that urgently need to develop green energy.