The article investigates how different eco-friendly vehicle types like electric and hydrogen cars can help cut greenhouse gas emissions when connected to the power grid. The research focuses on California's emission reduction goals and shows that a mix of smart charging, energy storage, and optimized fuel production is key for maximum impact. Plug-in hybrid fuel cell vehicles seem to have the best potential for lowering emissions due to their efficient technology and electric travel capability. To reach the emission goals, a lot more renewable energy sources are needed, especially for the different types of electric vehicles. Essentially, for cleaner cars to make a big difference, they need to work smartly with the power grid and rely heavily on renewable energy.