Why Power Factor Matters to Your Industrial Business

The quantity of energy used by global industry is enormous, and efforts are always being made to minimize usage, cost, and emissions. Monitoring power factor (PF) is one of the most important methods for reducing energy use because of its effect on prices and consumption.

These issues will be covered in this article:

1. Power factor (PF) calculation formula:
2. What brings on low PF?
3. How can PF be made better?
4. What does PF correction cost a company?

The Power Factor (PF) Calculation Process

The power factor in alternating currents (AC) is the ratio between the actual power utilized to accomplish work and the perceived power provided to the circuit. The power factor can have values between 0 and 1. When there is no actual power and just reactive power (often an inductive load), the power factor is 0. The power factor is 1 when all the power is real power and there is no reactive power (resistive load), as seen in Figure 1.

The Power Triangle in Figure 1.

PF is really a "expression of energy efficiency, a ratio of working power or Real Power, measured in kW to Apparent Power, measured in kilovolt amperes," according to a debate on Fluke.com (kVA). Kilovolt amperes resistive, or kVar, is the unit of measurement for the other component of the Power Triangle: reactive power. The quantity of power utilized to run machinery and other equipment over a specific time period is measured by apparent power, sometimes referred to as demand. By multiplying (kVA = V x A), it may be discovered. The outcome is given in kVA units.

Why are huge industrial enterprises so dependent on PF? Industry requires an enormous number of motors, compressors, pumps, and fans to manufacture its goods, all of which generate resistive load, or kVar.

Energy suppliers charge more to customers who have a lower power factor because they need more apparent power, measured in kva, than actual power, measured in kw, to complete the task. This additional fee is comparable to the cost of gasoline for a consumer driving a car with poor fuel economy.

A lower PF necessitates the following costs, which raises the price of the power distribution system:

• Insulation and other circuit components are damaged by heat.
• reduction in the quantity of useable electricity that is available
• larger conductor and apparatus sizes

Both resistive and inductive loads exist in every industry. Traditional incandescent lights and electric heaters are two examples of resistive loads. Motors, compressors, fans, and pumps are a few examples of inductive loads. As you continue to install inductive equipment, the ratio between these two types of loads grows increasingly significant.

What Brings on Low PF?

Reactive power, also known as kvar, or inductance, is produced while compressors, motors, pumps, and fans run. This is the inactive portion of the electricity that companies with low PF acquire at a cost to their business. Businesses with fewer motors, for example, are not affected by reactive power and do not notice the need for PF correction from larger industrial clients. Reactive power, or kVars, is needed to create and run an inductive load like a motor or compressor (kilovolt-amperes-reactive).

How Can PF Be Made Better?

Adding correcting capacitors that generate reactive current is the simplest way to raise the PF. Reactive generators increase the PF by offsetting the non-working power required by inductive loads such compressors, motors, pumps, and fans. The inductance produced by running motors, etc., is balanced by the capacitance produced by the capacitors.

The Value of PF Correction to a Business

With the same power triangle but two different PF values as shown in Figure 2, the example below illustrates how crucial PF may be for an industrial site.

Power Triangle in Figure 2 with Various PF Values

The influence on the quantity of energy used is significant in these two cases with PF values of 0.97 and 0.80. In contrast, with the lower PF of 0.80, the apparent power required is just 25% more than the real power, while the apparent power required with the higher PF of 0.97 is only 3% more than the real power. The savings from having a higher PF are USD 1,927,200 per year for a demand of 10 MW and an energy cost of USD 100 per MWh.