Impact of innovation in hybrid electric vehicles-related technologies on carbon dioxide emissions from the transport sector in Japan

Hybrid electric vehicles are increasingly recognized as a promising solution for reducing carbon dioxide emissions in the transportation sector. The current study examines the nexus between innovation in hybrid electric vehicle-related technologies and transportation sector-based carbon dioxide emissions from 1990 to 2019 using a variety of econometric techniques such as the structural breaks unit root test, Maki cointegration test, fully modified ordinary least squares, and dynamic ordinary least squares. The results show that innovation in hybrid electric vehicle-related technologies, renewable energy consumption, information and communication technologies, and international collaboration in technology development could help reduce transportation sector-based carbon emissions levels. By contrast, the findings indicate that gross domestic product, trade openness, and financial development have a positive nexus with transportation sector-based carbon emissions. Higher trade openness encourages economic expansion, and foreign trade may lead to more manufacturing, shipping, and transportation sector-based carbon emissions. Similarly, when gross domestic product and financial development rise, the need for highly energy-intensive items and services increases transportation sector-based carbon emissions. To minimize Japan's transportation sector-based carbon emissions, governments should emphasize innovation and adoption of hybrid electric vehicle-related technologies, boost renewable energy consumption, and prohibit emissions-intensive imports and exports.