If your industrial CFE bill has a charge for low power factor, you are paying recoverable money —probably thousands of pesos every month— with no one questioning it. The penalty shows up with a discreet asterisk and is paid automatically. The question almost no one asks is the right one: how much does that penalty add up to per year, and how long would the correction take to pay for itself?
This simulator lets you estimate your power factor penalty using the data from your own bill, step by step. And if you want the calculation fine-tuned to your case —with the correction investment and the specific payback for your plant— we deliver it personalized within 24 business hours, at no cost.
What you will receive
When you complete the contact form with four data points from your bill, in less than 24 business hours we deliver:
- Your annualized penalty — how much low power factor costs you today in pesos per year, not a generic percentage.
- The sizing of the correction — what type of capacitor bank (fixed or automatic) your plant needs and its investment range.
- The specific payback — in how many months the correction pays for itself at your penalty level.
- The next-step recommendation — whether it pays to correct now, what to require from the installer, and whether there are harmonics that complicate the case.
It is not a sales call. It is the concrete calculation, in writing, ready to take to your maintenance manager or your CFO.
How the calculation works (do it yourself)
While you wait for the personalized calculation, here is how it is estimated on the technical side. You only need your latest CFE bill.
Step 1 · Find your power factor on the bill
Look for the "power factor" section on your bill, usually in the middle or lower part. It is a decimal value between 0.50 and 1.00. Next to it you will see the "power factor bonus or charge" line:
- If it is a charge (positive), your factor is below 0.90 and there is a penalty.
- If it is a bonus (negative), you are above 0.90 and this calculation doesn't apply.
Step 2 · Apply the CFE penalty formula
CFE calculates the charge for low power factor with this formula:
Charge = (3/5) × ((0.90 / PF) − 1) × Billable amount
Where PF is your measured power factor and the billable amount is the subtotal it applies to. In practical terms, the approximate penalty based on your factor is:
| Power factor | Approximate penalty on the bill |
|---|---|
| 0.85 | ~3.5% |
| 0.80 | ~7.5% |
| 0.75 | ~12% |
| 0.70 | ~17% |
| 0.65 | ~23% |
Step 3 · Annualize the cost
Multiply the monthly charge by 12. This is where the number becomes relevant for an investment decision.
Worked example: a plant with a monthly bill of $1,000,000 MXN and a power factor of 0.80 pays a penalty of ~7.5%, that is ~$75,000 MXN per month → ~$900,000 MXN per year, recurring.
Step 4 · Estimate the investment and the payback
Compare that annual penalty against the cost of correcting it with a capacitor bank:
| Solution | Installed investment (MXN) | When to use it |
|---|---|---|
| Fixed bank (100–300 kVAR) | $80,000 – $200,000 | Stable reactive load |
| Automatic bank (300–800 kVAR) | $250,000 – $600,000 | Variable production |
| Active filters with compensation | $700,000 – $2,000,000 | Plants with harmonics |
With the penalty from the example (~$900k/year), even an automatic bank of $600k pays for itself in less than a year. Typical paybacks in Mexican plants with real penalties run from 6 to 18 months.
Another example: a mid-sized plant with a $400,000 bill
You don't have to be a large consumer for the case to be worthwhile. A plant with a monthly bill of $400,000 MXN and a power factor of 0.78 pays a penalty close to 9%, that is ~$36,000 MXN per month → ~$432,000 MXN per year. A fixed capacitor bank of $150,000 installed pays for itself in a little over four months, and from then on the savings are permanent.
The practical threshold: if the sum of your power factor charges over the last 12 months exceeds $100,000 MXN, there is already a clear business case to correct it.
Why your power factor varies month to month
If you review 12 months of bills, you will see that the power factor is not constant: it can swing between 0.78 and 0.88 over the year. The most common causes:
- Changing production mix: months with more large motors running lower the factor.
- Partial-load operation: motors and transformers working below their nominal capacity have a worse natural power factor.
- Degraded or disconnected capacitors: if you already have a bank, it may have lost capacity or have steps out of service.
That is why the personalized calculation uses the average of your history, not a single month: a good month can hide a recurring penalty the rest of the year.
What this simulator does NOT replace
This estimate is a coarse filter to find out whether you have a business case. If you decide to correct, you then need:
- Power quality measurement beforehand: power factor by circuit, reactive demand profile, and, above all, harmonic distortion. Installing capacitors without measuring harmonics can cause resonance and damage equipment.
- Detailed sizing of the bank (kVAR per step, capacitor type, protections).
- Result guarantee from the installer: a commitment to bring the factor above 0.95 as measured in billing.
All the technical detail —how to measure it, types of bank, what to require from the supplier, and the subsequent maintenance— is in the complete guide Power factor: why CFE penalizes you and how to correct it. This simulator estimates the cost; that guide explains the solution.
Request your personalized calculation
We need four data points from your bill. In 24 business hours we deliver the complete calculation with payback:
- Your current power factor (it's on the bill)
- The monthly amount of your CFE bill
- The power factor charge that already appears (if you can identify it)
- Your tariff type (GDMTH, GDMTO, HM)
Fill out the contact form here and mention "Power Factor Simulator" in your message. We respond in less than 24 business hours with the personalized calculation and the payback, no obligation.
To dig deeper in the meantime
- Power factor: why CFE penalizes you and how to correct it — the complete correction guide.
- Peak demand: how to control it and reduce your bill — the other recoverable penalty.
- Top 10 energy efficiency measures with the best ROI — where to place this correction among your investments.
- Industrial energy optimization: the strategic guide — the full framework of the three levers.
Frequently asked questions
CFE applies the formula Charge equals (3/5) times ((0.90 divided by your factor) minus 1) times the billable amount. In practical terms, the approximate penalty on the bill is 3.5% with a factor of 0.85, 7.5% with 0.80, 12% with 0.75, 17% with 0.70, and 23% with 0.65. The monthly charge is multiplied by 12 to annualize the cost.
CFE penalizes when the power factor falls below 0.90. On your bill it appears as a decimal value between 0.50 and 1.00; next to it you will see the power factor bonus or charge line. If it is a positive charge, your factor is below 0.90 and there is a penalty; if it is a negative bonus, you are above 0.90 and it doesn't apply.
It depends on your bill and your factor. A plant with a monthly bill of 1 million MXN and a factor of 0.80 pays close to 7.5%, about 75,000 MXN per month and 900,000 MXN per year, recurring. A mid-sized plant with a bill of 400,000 MXN and a factor of 0.78 pays close to 9%, about 36,000 MXN per month and 432,000 MXN per year.
Typical paybacks in Mexican plants with real penalties run from 6 to 18 months. A fixed bank of 100 to 300 kVAR costs between 80,000 and 200,000 MXN installed; an automatic one of 300 to 800 kVAR between 250,000 and 600,000 MXN; and active filters with compensation, for plants with harmonics, between 700,000 and 2 million MXN.
If the sum of your power factor charges over the last 12 months exceeds 100,000 MXN, there is already a clear business case to correct it. It is best to use the average of the history and not a single month, because a good month can hide a recurring penalty the rest of the year, since the factor tends to swing between 0.78 and 0.88.
