As first reported in Motor Trend, hybrid vehicles that operate on gasoline and electricity such as the Toyota Prius often produce less carbon dioxide than vehicles that operate solely on electricity such as the Nissan Leaf. The Motor Trend comparison analyzed the Prius, Leaf and Chevrolet Volt. The report also mentioned that as a result of electric battery life, the lack of charging stations, and current cargo capability, the Prius and Volt may be realistic vehicles for some people but the Leaf is a niche vehicle at best.
The Prius is a conventional gas powered vehicle with a supplemental battery that charges when the car is in motion. The Volt features a gas tank and electric battery and can be used in either mode. The Leaf is powered exclusively by an electric battery. The Volt and Leaf also require battery charging that takes four and seven and one half hours respectively.
The relative carbon dioxide emissions of the vehicles depends on the type of power source (fossil fuel, hydroelectric, nuclear). In 26 states, the hybrid Prius produces less carbon dioxide than the totally electric Nissan Leaf. The Leaf produces less carbon dioxide in 13 states and the District of Columbia; and the two are about equal in 11 states.
Even more surprisingly, a gas powered Chevrolet Volt produces less carbon dioxide than a battery powered Volt in 18 states. The electric powered version emits fewer CO2 emissions in only 29 states.
Electric vehicles may have enormous potential. However, in the short term they do not appear to offer much benefit in terms of reducing carbon dioxide emissions.