Eliminate the low power factor penalty on your CFE bill

CFE adds a penalty to the bill when the monthly power factor falls below 0.90. The official formula is: penalty (%) = ((0.90 / measured PF) − 1) × 100. At a PF of 0.85 the penalty is 5.9%, at 0.80 it is about 12.5%, and at 0.70 it rises to 28.6%. The penalty applies to the total amount billed (energy and demand), not just a portion. Once PF is above 0.90 it disappears, and above 0.95 CFE grants a bonus of up to 2.5%.

It depends on how the loads in your plant behave. A fixed bank works well when the inductive loads are on permanently and fairly stable (for example, continuous-process motors or pumps running 24/7). An automatic bank with modular steps is needed when there are large swings during the day (lines that cycle on and off, intermittent welding, cycling compressors), because over-compensating also draws a penalty: a capacitive power factor is punished just like an inductive one. The 7 to 14 day measurement beforehand settles the decision.

It is one of the electrical efficiency projects with the fastest payback on the market: typically between 6 and 18 months. The savings are direct (the penalty disappears from the monthly bill) and the investment is modest compared with a solar project or a full power quality program. An automatic bank of 200 to 400 kVAR for a mid-sized industrial plant runs about MXN 280,000 to 550,000 installed, and it typically eliminates monthly penalties of MXN 25,000 to 80,000. The exact figure comes out of the initial study.

Yes, and this is one of the costliest mistakes in power factor correction. When there is significant harmonic distortion (drives, welding, power electronics, induction furnaces), capacitors go into resonance with the network and burn out within months. The right solution is detuned reactors at 7% or 14% in series with the capacitors, or active filters when distortion is high. That is why we measure power quality before proposing anything: installing a bank without a diagnosis is a recipe for replacements and problems worse than the original one.

Connecting the bank to the main panel requires a short shutdown window, typically 2 to 4 hours, which we coordinate with your weekend maintenance or a shift change. The preliminary work (enclosure, wiring, base, conduit) is done while the plant operates normally. For continuous-operation industry that cannot shut down, we evaluate installing on branch circuits or switching to a backup transformer during the connection. The logistics are agreed in the proposal before any commitment.

It can, and it is important to anticipate it. PV inverters operate at a power factor close to 1, but when they reduce the active energy you draw from CFE without changing the reactive energy (which your motors and inductive loads keep drawing), the net power factor that CFE measures can drop and trigger the penalty. In all our solar projects we include a post-installation power factor analysis and, where it applies, a corrective capacitor bank in the original scope.