With the help of Sub
cooling, efficiency and the refrigeration effect of the system increases.
M.Zubair(2013) has done a experiment on vapour compression refrigeration system
with and without sub cooling for a low size application systems. By sub cooling
the power consumption of the system increases with increase in the cooling
capacity. The sub cooling has done by using the heat exchangers by flowing the
fluid in the sub cooler and refrigerant in the condenser. The authors has
compared the sub cooling effect with respect to different timings in the day
and concluded that the sub cooling effect is more when the ambient temperature
is high. Akintunde(2013) has done a experimental study on the blending of eco
friendly refrigerants which are alternatives for R12. He has done the
experiment on mixing of various ecofriendly refrigerants like R600a, R134a, R406a
in various proportions. From the results, COP will increase up to certain
refrigerant charge for maximum effectiveness. But when compared the cop with
respect to R12, The relative COP remains constant irrespective of refrigerant
charge. M.rasti(2011) analyse the refrigerants
performance by passing them through the refrigerator. By keeping four different
temperatures of freezer and refrigerant air temperature and from the results,
for high temperature freezer and refrigerant air temperature yields low energy
consumption. Also, the refrigerant charge and inlet evaporator temperature for
eco friendly refrigerants are less when compared to R134a. M.abuzar
qureshi(2011) has done the experiment on domestic refrigeration system under
steady state condition and analyse the performance with the help of R134a and
R600 refrigerants. They checked the energy consumption by keeping the bulbs in
parallel and series condition. The COP of the system is more when the energy
consumption of the bulbs is less. Global warming potential of R1234yf has less
than that of currently using refrigerators, Reasor(2010)  has investigated about the thermo physical
properties of R1234yf with comparison of R134a and R410 assuming same input
temperature and cooling load with the help of tube fin heat exchangers and
micro channel heat exchangers. A simple prototype is developed and they determine
the mass flow rates and pressures of each refrigerant and the analysis is made
by using vapour compression simulation software. Results have shown that both
R134a and R1234yf has similar output for same cooling temperature and load.
However the properties may differ from different designs of heat exchangers. With
the new technology developed and considering the energy saving shuanshi
jan(2017) has developed a hydrate based refrigeration system. Using methyl
fluoride, cyclopentane, and water are used as a working fluid in the system.
Three different type of inversions are done by using the hydrate disassociation
tank and hydrate formation tank. The maximum COP occurs when the  hydrate disassociation tank work as a evaporator
and hydrate formation tank as a condenser and heat from the gas and liquid
release separately from the system. The system performs 3 to 4times better than
conventional refrigeration system