The following calculator computes the expected loss reduction in percent for improving system power factor. Input the initial power factor and the compensated or corrected power factor to compute the expected loss reduction in percent.
Known variables: KVA, Initial Power Factor, Corrected Power Factor
Of Interest...
The power losses of an electric conductor depend on the resistance of the conductor itself and on the square of the current flowing through it. Since, with the same value of transmitted active power, the higher the power factor, the lower the current, it follows that when the power factor rises, the losses in the conductor on the supply side of the point of application of power factor correction equipment will decrease.
In a three phase system the losses are expressed as follows:
Therefore, improvement in power factor results in a corresponding decrease in current which results in a reduction in power losses by the square of the current reduction.
Electric utilities can often justify power factor correction on the basis of loss reduction due to the resistance and magnitude of power flow associated with long transmission and distribution lines. For industrial customers, justification of power factor correction on the basis of loss reduction is difficult as losses are comparably lower.
See NEPSI's released system capacity page for expected reduction in total power when applying power factor correction by clicking here.
Power factor correction on industrial power systems is most often cost justified (or mandated) based on power factor penalties and/or KVA charges, released system capacity, or the production benefits associated with improvements in power quality with the application of power factor correction equipment and harmonic filters.
In addition to losses associated with I2R losses from current flow through series resistance of power conductors, and transformer windings, a portion of power system losses come from hysteresis and eddy currents in the iron laminations of motors, generators, and transformers. These losses are not reduced by power factor correction and are largely dependent on system voltage rather than system current.
