This is all about effect of AC compressor on cars mileage. We will also cover about working and precautions to be taken to obtain good mileage of cars

1. EFFECT OF AC COMPRESSOR
ON CARS MILEAGE.

2. INTRODUCTION :-
 Your car’s air conditioner is an important accessory – it helps
keep you and your passengers comfortable and safe during hot
weather.
 However, it’s operated by your engine and places an additional
load on your engine when it’s running.
 That means it increases your fuel consumption (decreases your
fuel economy)

3. WORKING OF AIR CONDITIONERING SYSTEM :-
• Air conditioning's main principles are Evaporation and
Condensation, then Compression and Expansion.
 The air conditioner in a car draws power from the engine,
mainly to run the air compressor.
 An AC system employs a refrigerant flowing through a
compressor, condenser, expander and an evaporator.

4.  Compressor: The compressor is the workhorse of the air
conditioning system, powered by a drive belt connected to
the crankshaft of the engine. When the air conditioning system
is turned on, the compressor pumps refrigerant vapour under
high pressure to the condenser.
 The other main parts of air conditioner system are :-
1. Condenser Coil (Hot).
2. Evaporator Coil (Cool).
3. Chemical Refrigerant.
4. Fan (Blower).

5. picture shows how power is drawn from engine
and further used in cooling of cars interior.

6. Effect on mileage(fuel consumption) :-
 AC usage do increase the fuel consumption as the compressor
is coupled to engine and to run the compressor, engine has to
do more work.
 More work means more power required to do more work
which in turn means more fuel required to generate more
power.
 So longer the ac usage, more fuel is consumed.

7.  continuously using the air-conditioner could reduce the mileage
almost up to 20%.
 This mileage drop is even more prevalent when such cars go
uphill with the AC turned ON. This is simply because, more
load is put on the engine to move the vehicle against gravity.

8. Future advancements :-
 The belt-driven compressor is the mechanical type of the
compressor and this is a concept of the conventional air
conditioning (AC) system in automobile.
 Changing the power source for air conditioning system from
engine to electrical driven can reduce the load on engine and
increases fuel efficiency.
 Using electric compressor for automotive air conditioning
system and to reduce fuel consumption.

9.  This system is proposed so that the compressor speed is
independent to the engine crankshaft speed, thus better energy
efficiency and temperature control inside vehicle cabin.
 Electric compressor is easy to maintain and install to a compact
system and offers low energy consumption.
 If this can be implemented properly then there will be no effect
on mileage while using air conditioning system in cars

10. Electric compressor in car :-

11. Precautions to be taken to maintain a good
mileage
while using air conditioning in cars :-
o Regular oil changes and clean air filters can do a great deal
to improve your fuel mileage while using air conditioner.
o Ensuring that your AC system has the right level of
refrigerant is also an important consideration here.
o Clean the AC condenser located in front of the car near the
radiator regularly with high-pressure water.

12. o Clean the AC filter (if equipped with one) regularly, as we live
in dusty conditions.
o Don’t switch on the AC immediately after starting the car wait till
the engine warms a little and similarly switch off the AC first
before switching off the car.
o Driving with the air conditioner is more fuel efficient than
driving with the windows down. Driving with the windows
down creates drag which means that your engine has to work
harder to keep your car at the current speed; this burns more
fuel than if you just ran your AC.

13. Conclusion :-
 Most vehicle air conditioners require engine power to operate.
Of all auxiliary power requirements, a/c system use has the
greatest impact on fuel consumption.
 Using the AC can increase fuel consumption by up to 20%
because of the extra load on the engine. The load on eigine
depends on the vehicle’s interior size, the outdoor temperature
and other operating conditions.
 Manufacturers are developing more efficient AC system
technologies and control strategies to reduce the impact of an
AC system on fuel consumption. For example electric AC
systems are introduced to improve vehicle fuel efficiency.