This alert compares the measured Power Factor with a desired Power Factor.
Power factor (PF) is the ratio of the real power to apparent power and represents how much real power electrical equipment utilizes. It is a measure of how effectively electrical power is being used. Since a utility is paid based on energy consumed (kWh) and the reactive component of current does not register on a kilowatt-hour meter, many utilities impose a power factor penalty or peak demand (kVA) billing element for commercial and industrial customers to receive income for the total power they are required to deliver to a given customer. These charges differ from utility to utility and are expensive.
The most common methods are:
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Measuring reactive kilovolt-amp hours (kVAh) for customers with peak demand over x kW in addition measure kilowatt-hours (kWh). Interval meters record these values every 15 minutes.
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The kilowatt-hours and reactive kilovolt-amp hours are totaled for the month and a single calculation is performed to provide an average value of power factor for that billing period. A power factor adjustment of 0.06% is charged for each percentage point below x (0.85 to .95). Similarly, a credit is provided for each percentage point above x (not all utilities offer a credit).
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Some utility companies charge for demand using kVA instead of kW. The monthly bill is calculated by multiplying the demand by a demand rate ($/kVA)
Power Factor ideally is 100% but this is most often not achievable. You should strive for close to 100% however, but you also must deal with the equipment and its inherent capabilities. Some equipment, due to changes overtime, simply cannot achieve 100%.
Benefits - Depending on your situation, 12% to 25% energy expense reduction is not uncommon.