What is the relation between power factor and power consumption?

As we all know Total (Apparent) power = Real or Active power + Reactive power.

In a very simple language, power factor basically means, out of the total apparent power consumed by the load, how much useful or active or real power is present in it. In fact power factor is indicator of this above mentioned fact.

So, naturally power factor of unity (ideal case) indicates whole total power which is consumed by load is Active power or Real power, which means there is no reactive power consumed by load (case of Purely Resistive load).

As against this zero power factor indicates that no power will be transferred between the source and the load i.e whole power consumed by load will be just reactive power (just to get magnetized), no Active or real power is transferred which is actually used for doing useful work.

Consequences of low power factor and its effect on total power consumed by load:-

So, consider two loads, Load 1 and Load 2. Both have same power requirement for doing work (i.e Active power requirement). Now load one have low power factor, so as explained above out of total power which it draws from the source, Active power will have lesser share in it. load 2 has high power factor so the total power which it draws from source will contain more amount of Active power as compared to load 1 having lower power factor.

So, as the Active power requirement of both the loads is same, load 1 will have to draw more Apparent power (total power) as compared to load 2 which has high power factor, in order to have same amount of Active power as load 2.

Takeaway for you from this Answer:

A load with a low power factor draws more current than a load with a high power factor for the same amount of useful power transferred.

Thus, a load with low power factor will draw more apparent power as compared to a load with high power factor for the same amount of useful power transferred.

The higher current increase the energy lost in the distribution system, and require larger wires and other equipment.

Because of the above fact, Electrical utilities usually charges higher cost to industrial or commercial customers, where there is a low power factor.