One Unit of electricity saved by You ( In your House ) is equivalent to TWO unit of electricity generated ( By Power Plant )

Electricity must be generated, as and when it is needed since electricity cannot be stored virtually in the system.


How we can say that One Unit of electricity saved by You ( In your House ) is equivalent to TWO unit of electricity generated ( By Power Plant ). To prove this we have to consider the strcture of power system network.

Which is as follows

In India, for the coal based power plants, the overall efficiency ranges from 28% to 35% depending upon the size, operational practices and capacity utilization.

Then we transmit power through Transmission and Distribution Lines

The primary function of transmission and distribution equipment is to transfer power economically and reliably from one location to another.

If we consider the electricity flow from generation to the user in terms of cascade energy efficiency, typical cascade efficiency profile from generation to 11 – 33 kV user industry will be as below:

The cascade efficiency in the T&D system from output of the power plant to the end use is 87%
(i.e. 0.995 x 0.99 x 0.975 x 0.96 x 0.995 x 0.95 = 87%)



At the industrial end user premises, again the plant network elements like transformers at receiving sub-station, switchgear, lines and cables, load-break switches, capacitors cause losses, which affect the input-received energy. However the losses in such systems are meager and unavoidable.
A typical plant single line diagram of electrical distribution system is shown in Figure 1.3

The standard technical losses are around 17 % in India (Efficiency = 83%, as shown earlier).
But the figures for many of the states show T & D losses ranging from 17 – 50 %. All these may not constitute technical losses, since un-metered and pilferage are also accounted in this loss.

When the power reaches the industry, it meets the transformer. The energy efficiency of the transformer is generally very high. Next, it goes to the motor through internal plant distribution network.

A typical distribution network efficiency including transformer is 95%

and motor efficiency is about 90%.



Another 30 % (Efficiency =70%)is lost in the mechanical system which includes coupling/ drive train, a driven equipment such as pump and flow control valves/throttling etc.



Thus the overall energy efficiency becomes 50%.

(0.83 x 0.95x 0.9 x 0.70 = 0.50)   i.e. 50% efficiency).



Hence one unit saved at the end user is equivalent to two units generated in the power plant.

(1Unit / 0.5Eff = 2 Units)