What is Power Factor?

Power Factor (PF) is the ratio between the amount of total energy supplied (measured in Kilo Volt Amperes or KVA) and the amount of energy that does useful work (measured in Kilo Watts or KW). Some resistive equipment (heating elements, incandescent light bulbs, etc.) uses all the energy supplied to produce useful work. Since they are using 100% of the total energy supplied for useful work (producing heat and/or light) they have a 100 % power factor. Other types of equipment (motors, VFDs, etc.) require power to produce magnetic fields (KVAR) which must be established before useful work can be done. This type of equipment has a power factor of less than 100%.

For example: A motor requires current to create the magnetic field inside the windings that causes the machine to rotate at various RPMs and produce useful work. Magnetic field must also be maintained while the motor is running. Since some of the energy (KVA) is used to create these magnetic fields and the rest is used to do useful work (KW) the power factor is less than 100%. For a motor the power factor may be 80%. This means 80% of the total power (KVA) supplied to the motor is producing useful work (KW). The remaining reactive power (Kilo Volt-Ampere Reactive, or KVAR) is used to produce the magnetic fields within the motor.

How Do I Improve My Power Factor?

Access Energy Cooperative Supplies all the power needed for you to produce your products and services. This includes the portion that does useful work (KW) as well as the portion that creates the magnetic fields (KVAR) need by your equipment. (See What is Power Factor? above). There are two ways to improve your power factor. The first is when you purchase equipment. When specifying new equipment you can require the manufacturer to provide power factor correction on the equipment itself. There may be an additional cost for this, but it would provide the best possible power factor correction. The second is to add capacitors to your existing equipment. Capacitors provide the reactive power (KVAR’s) your facility needs to increase power factor. Since you are supplying this portion of the power the power purchased from Access Energy Cooperative has a higher percentage of useful power (KW) and a higher Power Factor.

For more information, please click here to contact our Engineering Department at 319-385-1557 or toll free at 1-866-242-4232.