Consider a system having following loads , we want to improve the system power factor to 0.95
| Equipment | Output KW | Efficiency | Load KW | Power factor | KVA |
| Motor A | 30 | 0.9 | 33.3 | 0.8 | 41.7 |
| Motor B | 90 | 0.92 | 97.8 | 0.85 | 115 |
| Lighting | 20 | 0.85 | 23.5 | 0.95 | 25 |
| Heaters | 10 | 10 | 1 | 10 | |
| Total | 150 | 164.6 | 191.7 |
Total load in KW = 164.6
And total load in KVA = 191.7
Therefore , the average power factor of the system will be = 164.6/191.7 =0.86
As we want to improve this system power factor from 0.86 to 0.95.
Existing power factor = 0.86 = Cos?1 ; therefore tan ?1 =0.593
Required power factor = 0.95 = Cos?2; therefore tan ?2=0.328
So, amount of capacitors to be installed to improve power factor will be
= Total Load (tan ?1 – tan ?2)
= 164.6(0.593-0.328)
= 44 KVAr