PowerFacAging calculator

Capacitors banks without proper maintenance:
> 25 % of expected savings are lost!

PowerFacAging is a very simple calculation sheet.
Its objective is to show how capacitor banks cave save you money,
but also to show that a significant part of the savings may be lost
if no proper maintenance is applied.

Without proper monitoring and maintenance of capacitor banks, the reactive power generated will be reduced after a period of time.
The reason can be a failure of capacitors or any other components in the system. This phenomena coupled with the possible increase of the power demand over the years lead to a loss of performance, and savings on the electricity bill being lower than expected.

To use our calculator, please fill-in the following:

Your profile :
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What is your main interest in using this calculator ?

To reduce the electricity bill
To understand the impact of capacitors aging
To evaluate the ROI of capacitor banks
Curiosity / Technical interest



Input data
kVA billing:

For simplification PowerFacAging is based on KVA billing. In this very simple mode of billing, the Utility measures the average power demand in kVA during a monthly period. The bill is calculated on a $/kVA basis.

To make your personalized calculation, fill-in your input data below:

Average monthly power demand

 InformationAverage value of the apparent power during a one month period. kVA (mini 100, maxi 2000)

Monthly billing

 InformationPrice of every kVA for one month $/kVA (mini 2, maxi 10)

Power factor before correction

 InformationAverage Power Factor of the plant before connection of any capacitor bank (cosφ1) (mini 0.6, maxi 0.9)

Power factor after correction

 InformationTargeted Power Factor of the plant after connection of a capacitor bank (cosφ2) (year 0) (>before, maxi=1)

Capacitor bank cost per Kvar

 InformationCost per kvar of the installed capacitor bank. Cost includes purchasing, installation, commissioning, spare parts, etc... $/kvar (10 ... 50)

Capacitor bank age

 InformationTime of operation of the capacitor bank since commissioning. It is considered that the reactive power generated by the capacitor bank is stable during the 5 first years of operation, and then decreases by 10% every year. Years (between 10 and 15)