Power Factor Correction

• How will power factor correction benefit my business?

  There are many benefits to installing power factor correction equipment and actually very few drawbacks.

  Firstly, as an energy efficient technology, power factor correction equipment qualifies for the low interest Energy Efficiency Financing Scheme from the Carbon Trust and Siemens Financial Services. We can even help you to complete the paperwork for affordable and flexible payments that are designed to be offset against the anticipated energy savings so that your power factor correction investment can pay for itself from the outset.

  Once installed, the ongoing benefits of power factor correction include:

  • Reduced electricity costs that can range from £100’s per annum to £10,000’s depending upon the size and nature of your electrical system.

  • Reduced I²R losses mean reduced heating effects upon your distribution equipment and therefore increased longevity of expensive capital plant.

  • Increased kVA availability for plant expansion. By improving your power factor and reducing the amount of electricity that you draw from the supply, an increased electricity supply from the utility company may not be necessary to squeeze in that extra machine that you’ve been thinking about.

  • Reduced voltage drops at the end of long cable runs improve motor starting characteristics.

  • Reduced carbon footprint as a direct result of your reduced electricity consumption.

  • Improved energy efficiency is good for both the environment and for your company’s image.

• Why/how do the utility companies charge for poor power factor?

  Utility companies charge half-hourly metered industrial and commercial electricity users for operating at low or poor power factor. Why?… because poor power factor equates to electrical inefficiency and necessitates increased electricity generation and distribution.

  Power factor charges, (or penalties as they are often referred), can potentially increase your electricity bill by up to 20% if your system operates at a low power factor. Charges that are directly affected by power factor can take the form of many guises depending upon the electricity supplier and the type of tariff that you pay. The most common type of charges directly affected by power factor are briefly explained below:

  •Reactive Power Charge – Reactive power (kVAr) is directly affected by power factor: if your power factor is low, then your reactive power demand will be high (relative to your kW demand). The reactive power charge is levied for kVArh consumed in excess of (typically) 33% of the kWh consumed. This equates to an average power factor of approximately 0.95, so if your electrical system operates with an average power factor below this figure then you will be charged for excess reactive power.

  • kVA Standing Charge or Agreed Supply Capacity – Apparent power (kVA) represents the total power that you draw from the supply and is also directly affected by power factor: if your power factor is low, then your kVA demand will be high (relative to your kW demand) and your agreed supply capacity with the utility company will therefore need to be higher than if your system operates with a high power factor.

  Correctly applied power factor correction will instantly eliminate reactive power charges and enable a reduction to your kVA standing charge or agreed supply capacity.

• What power factor correction solutions can Enspec offer?

  Over the years, we have manufactured and installed just about every manner of power factor correction scheme conceivable. Our VArComp^® range of power factor correction equipment can be manufactured to any kVAr/MVAr output at distribution levels from 400V up to and including 36kV. We have power factor correction installations across the Globe from Dubai to the Arctic Circle, in many diverse applications including:

  

  Application of the latest technology, quality assurance and extensive experience is built into every VArComp^® product which includes:

• Automatic power factor correction

  By far the most commonly applied equipment and sometimes referred to as ‘bulk’ power factor correction as it tends to be installed at or close to the main electricity incomer to correct the power factor of the entire electrical distribution system.

  The VArComp^® X_C range continuously targets a given power factor, (typically ≥0.95), by monitoring and comparing the phase angle between the supply voltage and current. Capacitors and/or inductors are switched into and out of circuit by electro-mechanical contactors as required to maintain the target power factor.

• Static power factor correction

  Capacitors and/or inductors provide the reactive power compensation to correct the power factor of steady-state electrical loads and individual motors. 

• Detuned power factor correction

  Suitable for application on harmonic-laden systems, the VArComp^® X_CL range of detuned power factor correction equipment utilises capacitor/inductor tuned circuits to prevent both harmonic overload of capacitors and to avoid potential harmonic amplification caused by resonance between the capacitor bank and supply transformer. Detuned power factor correction can also provide a certain level of harmonic dampening.

• Dynamic (real-time) power factor correction

  Similar in concept to automatic power factor correction but with much faster response. Often referred to as ‘real-time’ power factor correction, thyristor-switched capacitor banks provide the necessary reactive power compensation for rapidly changing dynamic loads.
  The VArComp^® Q-VAr can respond from zero to full kVAr/MVAr output (or any step output in between) within one cycle (20ms @ 50Hz) and is often used in voltage control applications such as flicker compensation as well as power factor correction.

Whether you are looking to apply power factor correction to reduce your electricity costs or free up some much-needed kVA availability for plant expansion, we can provide a turnkey solution to all of your power factor correction requirements from initial feasibility studies and load surveys through to system modelling, design, manufacture and installation.

By investing in power factor correction, you will immediately improve your energy efficiency, help the environment and save money by reducing energy costs. For more information, please contact us. We will be pleased to help, whatever your requirements.