Efficiency of Electric Motors vs. Gasoline Engines

Traditional cars use an internal combustion engine that burns fuel to create energy.

Gasoline has a higher energy density than batteries, which means that batteries need to

be bigger and heavier to provide the same amount of energy. However, electric motors

are much more efficient — about 90% efficient, compared to around 25% for gasoline engines.

Also, electric motors can reuse energy during braking, while fuel engines

cannot “unburn” gasoline.