The main disadvantage for gas powered cars is the fact that they burn gas and have no way of getting rid of all the after products with out sending them into the air. These after products include CFCs , Carbon Dioxide , Sulfur Oxides , Lead , Benzene , Carbon Monoxide , Methane , Hydrocarbons and Nitrogen oxide , and tropshperic ozone . Sulfur oxides contribute to acid rain. Lead disrupts the nervous system. Benzene can cause cancer.
Carbon monoxide causes cardiac, circulatory and respiratory problems.
Hydrocarbons causes nose and eye irritation, chronic lung problems, asthma, bacterial infections. And they also can harm the forests and crops you eat. As the fact remains the only emissions for electric cars is water. Another problem solved is that if you decide to get rid of your electric car, if it sits for a long time it dosen't leak oil by products. And also it reduces the leakage of battery acid and lead from the gasoline.