Power Factor Correction

¡¡¡¡¡¡Get a Bonus of 2.5% of your electric energy consumption for FREE!!!!

Get all the advantages and benefits of a High Power Factor according to complementary dispositions. (México)

Do you realize how much Money you are wasting with a low power factor?

Investment in capacitor Banks to correct low power factor can be one of your best investments, with Internal Rates of Return of over 60%

Let our bank put money in your bank.

Know the benefit of keeping a high power factor in your facility.

Power factor correction (PFC) is the process of adjusting the characteristics of electric loads in order to improve power factor so that it is closer to unity (1). Power factor correction may be applied either by an electrical power transmission utility to improve the stability and efficiency of the transmission network; or, correction may be installed by individual electrical customers by installing capacitors to reduce the costs charged to them by their electricity supplier. A high power factor is generally desirable in a transmission system to reduce transmission losses and improve voltage regulation at the load.

Monthly Bills

Managing the monthly electric bill is an ongoing challenge. For most industrial plants, reducing electricity costs means limiting peak demand or installing energy-saving equipment. But there is a portion of the monthly bill that can be decreased without altering usage or usage patterns. Power factor represents a significant part of the electric bill for many plants, yet is often one of the most controllable costs. Further, poor power factor increases power system costs in three other ways.

What is Power Factor?

Power factor is the difference between the total power your utility delivers to your facility and the portion of total power that does useful work. Real power, in kilowatts, measures useful work; reactive power, in kilovars, measures the fields needed to allow real power to be consumed.

Reactive power is expensive to deliver to loads with large reactive requirements. Utilities charge power factor penalties to recover the additional costs they incur serving poor power factor loads. Penalty amounts depend on utility rate structures and commission policies.

Although some customers do not pay additional charges for poor power factor, improving power factor can still save money in three other ways.

Poor power factor loads require the power system to transmit more current, delivering more total power than necessary to do useful work. In effect, poor power factor loads can be thought of as requiring two different kinds of current: the part that supplies real power and the part that provides reactive. Both are necessary in ac power systems, but it is not necessary for the reactive portion to be provided by the source of real power. As we will see, power factor correction capacitors can supply reactive current anywhere on the power system.

Why do we need to improve Power Factor?

There are at least four reasons to correct poor power factor at a facility:

• Reduce power factor penalties
• Reduce energy losses due to excessive currents (I2R)
• Improve voltage regulation
• Release system capacity

Power Factor and Harmonics

Capacitors do not generate harmonics, but their connection to a power system can change that system’s ability to transmit harmonic currents. If the changes are severe enough to send the power system into resonance, equipment protective and control system misoperation and damage can result. Harmonic resonance can be avoided by installing harmonic filters instead of Simple Capacitors. Filters provide power factor correction, but are also designed to remove specific harmonic currents from the power system. In addition to possible resonance problems, harmonic loads can fool you into believing that Capacitors are needed when they are not. Harmonic loads reduce true power factor, the ratio of real power to total power, which includes all power system frequencies. They may or may not contribute to poor displacement power factor, which is the time lag between fundamental (60 Hz) voltage and current. Capacitors correct only displacement power factor. That is why measuring the electrical system before decisions are made is very important to determine both true power factor and displacement power factor.

How can you determine if harmonics will be a problem?

With any sizable (kvar more than about 25% of the transformer rating in kVA) Capacitor installation, a harmonic assessment should be conducted. This involves measuring the amount of harmonic currents at the proposed Capacitors site, and calculating the resonance potential. Energiza/Atee Corp provides power quality assessments and studies. Complete turnkey Capacitors and harmonic filter installations can be arranged.

Conclusion

Poor displacement power factor reduces the capacity of the power system and increases its operating costs. PFCs offer four benefits, but their installation can aggravate harmonic problems. Energiza/Atee Corp. provides Capacitor and harmonic filter assessments, and solves power quality problems related to existing Capacitor installations.