how much a plug-in electric vehicle (PEV) can reduce greenhouse gases depends on the source of the electricity used to charge its batteries. Coal-fired plants produce the most greenhouse gases. However, even in regions where most electricity is produced by coal, electric cars still reduce greenhouse gases by 25-30 percent over conventional vehicles. When charging from nuclear power or renewable energy sources, such as hydro-electric, wind or solar power, electric vehicles reduce pollution even more dramatically.