Power factor correction – Addressing the myths
Power factor is a subject that has a great deal of confusion and many misconceptions surrounding it. Before we can go into addressing and dispelling the myths about the technology, the question of what is power factor and what is power factor correction, needs to be out of the way.
Power factor is the ratio of active power over apparent power and it is a measure of how efficiently the electrical energy supplied to a particular electrical device or system is being utilized. So, if power factor is the concept of determining just how much more electrical supply is required to power a load, aside from the actual power that that load consumes, then power factor correction is the process of improving the power factor level of a certain electrical system and ensuring a reduction in the associated apparent power (maximum demand).
The main culprit in the various doubts and misconceptions about power factor correction lies in the fact that most people do not fully understand the concept of power factor correction. A second issue is that there are unscrupulous businesses which offer power factor correction solutions which are either of poor design or which cannot deliver the promised and desired results. As a result, there is always a lingering doubt whether an investment into power factor correction technology is 1. worth it and 2. effective in the long term.
- What is power factor correction technology? This technology consists of installing equipment on site, which automatically generates (most of) the reactive power consumed by an electrical system. In doing so, the utility no longer has to supply (most of) the reactive power consumed by the system, which in turn reduces the apparent power consumed. Reactive power is typically generated by capacitors with are fitted inside an automatic power factor correction system}
- Installing power factor correction saves energy. The question of energy savings as a direct result of the installation of PFC equipment is two-fold. From a semantics viewpoint, the answer is no, power factor correction does not reduce the total energy consumption of your plant. What it does do is reduce the total power being drawn from the grid: since the PFC equipment generates the reactive power consumed by your plant, it is no longer drawn from the grid. In other words: from a utility/grid point of view, your plant becomes more energy efficient. Power factor correction interventions can therefore result in significant savings in energy bills through the reduction of apparent power (Maximum Demand – kVA) or when the utility imposes a low power factor penalty in their rate structure, as is the case in most industrialised countries.
- Falsehoods related to power factor correction technology
Power factor correction equipment can NOT do the following:- Phase load balancing
- Assist in “riding through” power dips
- Surge protection
- Harmonic filtration
- Reduce active energy consumption (kWh) in any meaningful way
- Reduce the carbon footprint of your plant in any meaningful way
- Improve the fuel efficiency of generators.
- Claims of savings in residential homes with an electricity saving box
Many homeowners have fallen victim to the oversold dream of an electricity saving box. Advertising and revenue marketers of the product will claim savings of 30-60% (almost instantaneously), meaning constant decreases in your electricity bill each month.
In truth, what’s happening with the add-on of an electricity saving box is the following:
- The electricity saving box reduces the apparent power consumption of the residence by reducing the reactive power consumption
- Utility providers however only charge for the active power consumption, which the electricity saving box cannot reduce
- The fitment of an electricity saving box therefore does not result in any savings in electricity costs, for the residential electricity consumer.
If you have any doubts or would like to know where to start, contact us, the experts.