cars are the most efficient cars today due to
their inclusion of regenerative braking, low
heat generation, and near zero
energy spent when idle.
braking is a breakthrough that adds driving
range by returning the car’s kinetic energy to
In gas cars, that energy is lost
to heat in the brakes. Regenerative braking
works when stopping, the motor now putting
energy back into the batteries, acting as an
“An additional benefit is
that regenerative braking keeps the electrolyte
from forming layers of acidity within the
battery. This increases the efficiency and life
of the battery” (Whitener 37).
Good efficiency is hard to achieve in an
internal combustion engine car, because
combustion creates heat.
Each energy transfer through a gear or bearing
loses additional heat in the drive train,
totaling eight to nine percent.
“The internal combustion engine is
notoriously inefficient. [Internal combustion]
engines have an efficiency of 20-25% and diesel
(EV’s) overall lose about 40% of their
propulsion energy to heat, because they use a
fixed gear ratio instead of a variable ratio
transmission, and concentrate heat in the
Energy Spent when Idle