There are many benefits to running an electric or hybrid car. These affect both the environment and your bank balance in a positive way. When compared to an internal combustion engine car, an electric vehicle uses its fuel more efficiently and so is cheaper to run.
People who criticize electric and hybrid cars
say that unless the electricity to run them comes from a green source such as
solar or wind power, there is little point owning one. It is beyond doubt that
generating electricity by these renewable means is a preferred option, but even
if this is not the case it is still better to run an electric vehicle rather
than a petroleum driven one.
How is this so?
There are two significant reasons. Firstly,
electric and hybrid cars are more efficient in their use of energy than
conventional powered cars, regardless of the source of that energy. The second
reason is that energy from the mains grid is itself more efficient than energy
from burning petrol, even if the grid is powered by coal fired power stations. Each
of these points needs to be examined in detail.
Both electric and hybrid cars use electric
motors to turn the drive wheels. The motors operate through the use of magnetic
fields. Since magnetism is a non-contact force there is no need for contact
between the drive wheels and any type of drive shaft. This reduces friction,
and so uses less energy. When an electric vehicle brakes the magnetic fields
are reversed and the forward motion of the car is converted into electricity.
This electricity is then used to recharge the batteries, making the car even
more efficient. This process is called regenerative braking and is standard on
all electric cars. By comparison, petroleum powered cars not only produce a lot
of friction, they rely on it to function. There is a flywheel on the rear of
the engine that is physically connected to the drive train of the car. This is
then connected to the drive wheels and through this contact the car is
propelled forward. When the car brakes, the energy of the car's motion is removed
through friction between the brake pads and the brake discs. This means that
when it brakes, a petroleum driven car loses all the energy of its motion.
The second point concerns the efficiency of
the mains power grid. Power stations have a long history and are designed to be
as efficient as possible. It is true that almost all of the mains energy still
comes from power plants burning fossil fuels, but these plants generally work
in the range of 40 to 50% efficiency, which is the conversion of the chemical
energy in the fuel into electricity. By comparison, gasoline powered internal
combustion engines operate at about 25% efficiency. So it is a reasonable
conclusion that a vehicle run from grid energy will be about twice as efficient
as the same vehicle run from non-grid energy such as petroleum, and will
therefore produce far less pollution.
The last point about the efficiency of the
grid becomes more pronounced if the electricity is sourced from a renewable
supply. In that case an electric car running off the grid becomes extremely
efficient. While running efficient public transport in such a manner would be
even more efficient, it seems that cars are here to stay so it makes sense for
them to be as energy efficient as possible.
Critics may say that the energy savings of
electric cars are minimal, and that this is not a sufficient saving to make
them worthwhile. However, any step forward is a step in the right direction and
so it is worth being mindful of the environmental and economic benefits of
these vehicles.
1 Comments
Great explanation. Thanks for sharing the detailed about hybrid and electric vehicle advantages.
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