Capacitors Help Reduce Electric Bills
Have you ever taken a close look at your electric bill? To the untrained eye, taking a skim through a commercial electric bill can be an intimidating task. Everything from demand charges, on-peak & off-peak line items, delivery, and transmission – the list can be exhaustive and confusing depending on the utility provider. Unless your staff has a trained energy manager or facility engineer, it can be tempting to simply pay the monthly charges and move on.
One such charge that may appear on your electric and could subliminally be racking up your bill is the power factor (PF) charge, sometimes referred to as a power factor penalty.
What is Power Factor?
When the electric utility supplies electricity to your facility, they are supplying what is called Apparent Power (VA) – the amount that will show up in metering equipment and looks like it is being consumed in the facility. In reality, not all the electrical energy being delivered to the facility is being used to perform work; i.e., move machines and power lights. Particularly, AC motors require what is called Reactive Power (VAR), necessary for generating an electric field (and thus turning the motor) within the motor itself. The energy to perform the work itself is the Active Power (W). The PF, then, is a ratio of the Active Power to the Apparent Power. Many other pieces of equipment such as solenoids, lifting magnets, and arc welders can also negatively affect facility PF.
Therefore, a PF close to 1 indicates a very efficient circuitry system within the facility. The power coming into the building is almost all being utilized to perform useful work. The lower the PF, the more inefficient the circuitry, and the utility company must supply more energy than is actually being consumed. Therefore, the end user is penalized with a PF penalty charge on their electric bill.
Correcting Power Factor
The Reactive Power necessary for AC motors causes the power factor to fall behind the active power, producing a lagging PF. Correcting for this is actually quite simple; a bank of capacitors can be installed behind the meter to correct for the apparent power lagging. This will correct the PF and get it much closer to 1. As a result, penalty charges will disappear from your bill. Additionally, correcting the power factor can improve voltage quality and reduce power losses in transformers, feeders, and power distribution equipment.
If you think you may have issues with your facility’s PF, contact Improv Engineers today. We have veteran engineers ready to perform a power analysis of your facility.