A poor power quality manifests itself as frequent voltage fluctuations. When your equipment does not get optimum voltage, it consumes excessive energy. This energy wastage is, however, invisible & goes unnoticed, but this poor quality power will have a great impact on our energy bills as well as our costly equipment could be damaged due to this voltage fluctuation. Voltage optimization in an electrical energy system will helps us in saving the energy.
Now we consider the two cases i.e Over Voltage and Under Voltage, in the first case i.e in case when the voltage is higher than the voltage at which equipment is designed to operate most effectively the lifetime will be reduced and consumption in energy increases without any improvement in performance. Similarly in second case when the voltage goes below the rated voltage, number of problems are generated in the equipment, for example contactors and relays may drop out which may further lead to interruption in operation of machines.
Besides the above two causes there is one another factor which have a great impact on voltage optimization i.e imbalance of phase voltages. Unbalancing between the phase voltages generates the various problems like heating motors and wiring, increased energy consumption etc.
According to a report published by Department of Electrical Engineering, IIT Kanpur, in India 4 to 6% of generated energy is lost in transmission and 15 to 18% energy is lost in the distribution system. It is also concluded that voltage variation plays a very vital role in loss of energy in distribution system. If we  arrest this voltage variation than definitely we can save the 10% of energy loss from distribution system.
Here we are showing some test case on how to save the energy by controlling the voltage variation or by voltage optimization.

Test Case 1: Saving on Motive Load: General Machines

Following test of KW consumption on assorted motive load of a cable plant conducted at various voltages will help you calculate the potential savings on your general motive load. The rated voltage of the machine in consideration is 440V.

                     
 Voltage in 3 phase
    KW consumption
                381
                 15.7
                390
                 16.2
                400
                 16.8
                414
                 17.5
                424
                 18.3
                433
                 19.2

Thus, if your plant gets a voltage of 433 for 8 hrs, & you stabilize your voltage at 400 V, your saving potential is (19.2 – 16.8)/ 19.2 x 100 = 14%approx. for those 8 hours.
You can judge for yourself as to how much you will save.

Test case II saving on motive load  :Compressors

Following test of KW consumption on compressors of a textile mill will help you calculate the potential savings on compressors. The rated voltage of the machine in consideration is 440V.

 Voltage in 3 phase
    KW consumption
                442
                 93.8
                433
                 92.4
                418
                 91.6
                402
                 88.8
                382
                 88.1

Thus, if your compressor gets a voltage of 433 for 8 hrs, & you stabilize your voltage at 400 V, your saving potential is 92.4 – 88.8 / 92.4 x 100 = 4% approx. for those 8 hours.
2. Energy Saving by Using servo voltage stabilizer
           
So above we have illustrated that how energy is saved with voltage control. This can easily be done using servo voltage stabilizer. However if efficiency of voltage controller is poor, than the benefit of energy saving is lost. Therefore one important thing has to be taken in account during designing of voltage controller that is efficiency has to be more than 98% and only then we will be able to save the energy through voltage control. Our “POWERWARE” brand has high efficiency models of servo voltage stabilizers which have efficiency of about 99%.
for more details you can visit our website-http://www.saielectricals.com/