Examining Diverse Investors in the Clean Energy and Environmental Technology Sector: A Network Analysis from Japan

Startups in the clean energy and environmental technology (CEET) sector can develop sustainable innovations, but mobilizing private finance has been difficult. As the venture capital (VC) investment model was found to be not well-suited for the CEET startups, diverse types of investors have received more attention. However, since previous studies have been dominated by a VC-centric perspective in the US and have overlooked collaborative relationships, the roles of various CEET investors have not been systematically analyzed. This study aims to analyze the diverse investors in the CEET investor network formed through co-investment syndication, using Japan as an underexplored regional context. Based on Japan’s comprehensive data from 2008 to 2022, this study examines the evolution, structure, and communities of the network. The analysis identified the development stages of the investor network: the formation stage (2008–2012), the expansion and diversification stage (2013–2017), and the stable growth stage (2018–2022). The results confirmed the strong influence of VCs, while a community analysis suggested the bridging role of governmental venture capital. The findings based on the CEET investor network contribute to expanding both the theoretical understanding and practical implications for overcoming the financing difficulties of CEET startups to address the climate change crisis.