Power factor correction: stop paying for power you don't use.
Motors, transformers and drives draw reactive power that does no useful work but still loads your supply. Correcting power factor reduces utility charges, cable losses and the strain on your transformer.
What is power factor?
Real power (kW) does the useful work. Reactive power (kVAr) magnetises motors and transformers. Together they make up apparent power (kVA), which is what your cables, transformer and utility actually have to supply. Power factor is the ratio of real to apparent power.
At a power factor of 1.0, every kVA supplied does useful work. At 0.7, a site draws about 43% more current than it would at unity for the same work, and pays for it in losses and charges.
Why low power factor costs money
- Utility charges and penalties for reactive power or low power factor on commercial and industrial tariffs
- Higher demand charges where demand is billed in kVA
- Extra current heats cables and transformers, wasting energy
- Less spare capacity on transformers and switchgear when you want to expand
How we correct it
We measure the site's reactive demand and harmonic content first, then design automatic capacitor banks that switch steps in and out as the load changes. Where drives, UPS systems or LED drivers create harmonics, we use detuned banks or combine correction with harmonic filtering, so capacitors are not damaged by resonance. Our technology partners include Lovato Electric for power quality equipment.
Before we recommend anything, a feasibility study measures your site and estimates the saving. After installation, savings are measured and verified to IPMVP and reported monthly.
From measurement to verified savings.
Every measure follows the same process, and can be bought outright, leased or delivered under an Energy Savings Performance Contract with no upfront capital.
- Feasibility studyAnalysis of the facility's energy consumption, losses and savings potential.
- EngineerTechnical design and a bankable business case covering investment, savings and payback.
- FinancingSupport in securing financing, including the documentation lenders require.
- ImplementProcurement, installation and commissioning by our own engineers.
- VerifySavings measured to IPMVP on our EnMIS platform, reported monthly.
- MaintainPreventive maintenance for the full contract term, so that savings are sustained.
Frequently asked questions
What power factor should we aim for?
Most sites aim for 0.95 or higher, comfortably clear of utility penalty thresholds. The right target and bank size come from measured load data.
Why do capacitor banks fail?
Common causes are harmonics, resonance with the network and over-voltage. We check harmonic levels before designing a bank and use detuned designs where needed.
Does power factor correction reduce kWh?
Its main benefit is lower reactive power charges, lower current and spare capacity. It also reduces resistive losses in cables and transformers, a smaller kWh saving.
Related services and technologies.
Paying reactive power charges?
Send us a recent electricity bill and we'll tell you what power factor correction could save.