In recent years, the proliferation of electric vehicles has accelerated, leading to a closer interaction between transportation and power systems. This synergy offers significant technical support for enhancing carbon reduction efforts within the transportation sector. This paper examines the achievements and potential for carbon reduction in transportation, exploring the application methods and future prospects of renewable energy as a clean power source across various transportation modes. It discusses the current integration of power and transportation systems, highlighting the integrated approaches and intelligent management capabilities of vehicles, infrastructure, and renewable energy. Additionally, it emphasizes the positive influence of policies and regulations in facilitating this integration. Finally, the paper anticipates further strategies for the coordinated development of the transportation sector and renewable energy from both technical and policy perspectives.