An HFEV is an all-electric car featuring an open-source
battery in the form of a hydrogen tank and the atmosphere.
HFEVs may also comprise closed-cell batteries for the
purpose of power storage from regenerative braking, but this
does not change the source of the motivation. It implies the
HFEV is an electric car with two types of batteries. Since
HFEVs are purely electric, and do not contain any type of heat
engine, they are not hybrids.
8. ENVIRONMENTAL IMPACT:
FUEL CONSUMPTION:
Current HEVs reduce petroleum consumption under certain
circumstances, compared to otherwise similar conventional
vehicles, primarily by using three mechanisms
1. Reducing wasted energy during idle/low output,
generally by turning the ICE off
2. Recapturing waste energy (i.e. regenerative braking)
3. Reducing the size and power of The ICE, and hence
inefficiencies from under-utilization, by using the
added power from the electric motor to compensate
for the loss in peak power output from the smaller
ICE.
Any combination of these three primary hybrid advantages
may be used in different vehicles to realize different fuel
usage, power, emissions, weight and cost profiles. The ICE in
an HEV can be smaller, lighter, and more efficient than the
one in a conventional vehicle, because the combustion engine
can be sized for slightly above average power demand rather
than peak power demand. The drive system in a vehicle is
required to operate over a range of speed and power, but an
ICEs highest efficiency is in a narrow range of operation,
making conventional vehicles inefficient. On the contrary, in
most HEV designs, the ICE operates closer to its range of
highest efficiency more frequently. The power curve of
electric motors is better suited to variable speeds and can
provide substantially greater torque at low speeds compared
with internal-combustion engines. The greater fuel economy
of HEVs has implication for reduced petroleum consumption
and vehicle air pollution emissions worldwide.
NOISE:
Reduced noise emissions resulting from substantial use of the
electric motor at idling and low speeds, leading to roadway
noise reduction in comparison to conventional gasoline or
diesel powered engine vehicles, resulting in beneficial noise
health effects
POLLUTION: Battery toxicity is a concern, although today's
hybrids use NiMH batteries, not the environmentally
problematic rechargeable nickel cadmium. "Nickel metal
hydride batteries are benign. They can be fully recycled
9. BENEFITS OF HEV:
Reducing wasted energy during idle/low output, generally by
turning the internal combustion engine off.
Recapturing waste energy
Reducing the size & power of the ICE engine
10. DISADVANTAGES:
COST:
One of the main disadvantages of HEVs is that they cost more
than conventional vehicles of the same or similar model.
Online hybrid car information resource Hybrid Cars estimates
that an HEV costs an average of $5000 to $7000 more than a
non-hybrid version of the same car. Overall costs of owning a
hybrid decrease over time due to a higher mileage per gallon
rate, which means a reduction in the usage of gasoline.
However, this is not always a consolation for those who
would like to buy a "green" vehicle but cannot afford the
initial price tag.
BATTERY LIFE AND FUNCTION:
Buying an HEV may mean that you will be spending more
money on batteries over the life of your car, according to
Hybrid Cars. Electricity to a hybrid is provided through the
battery, and some car owners worry that the heavy demand on
the battery could cause it to expire more quickly. However,
research has not proven this theory as of yet.
Some hybrid batteries are slower on the uptake in cold
weather, according to Green Footsteps. This delayed reaction
in the winter may mean more gas usage, which defeats the
purpose of owning a hybrid. Frequent charging requirements
may also be a disadvantage if you do not use your vehicle for
weeks at a time. You might encounter delays on the road if
you forget or do not have the opportunity to charge your car
before heading to work.
11. CONCLUSION:
HEV technology for both light and heavy duty applications is
commercially available today and demonstrates substantial
reductions in tail-pipe emissions and fuel consumption, even
when compared to other available low emission
technologies .HEV are particularly effective for urban travel,
significantly lowering pollutant emissions and providing costeffective
CO2reductions in personal mobility. Encouraging
hybridization of vehicle fleets through enabling policies and
incentive structures can serve to lower both conventional and
CO2 emission ,thus improving public health, energy security,
and reducing fuel costs. Continuing innovation in hybrid
technology and a growing demand for cleaner vehicles will
mean that costs are like to fall, particularly in second hand
vehicle markets