On kVAh billing, judge the site by the derived power factor (kWh divided by kVAh), not the printed one. Every point below unity is billed silently in the units themselves.
By the numbers
A kVAh-billed consumer at 0.90 average PF buys 11.1% more apparent-energy units than the same kWh load at unity PF.
Source: Power-triangle identity
A bill that shows both kWh and kVAh lets you derive the real average PF as kWh divided by kVAh.
Source: Power-triangle identity
Reactive energy can be reconstructed from bill energy as kVArh = sqrt(kVAh^2 - kWh^2).
Source: Power-triangle identity
If kVAh is present, BillTrends uses kVAh rather than kWh for the bill's unit denominator.
Source: BillTrends default model
BillTrends classifies charge lines into demand, fixed and variable families before comparing bills.
Source: BillTrends default model
What kVAh billing changes
On kWh billing, reactive power shows up as an explicit PF penalty or incentive row. On kVAh billing, the meter records apparent energy, which already includes the reactive component. At 0.90 PF, every 100,000 kWh behaves like 111,111 kVAh on a kVAh tariff.
That is why the printed PF on a kVAh bill is often 0.99 or 1.00: it is a near-tautology of the billing basis, not a health certificate for your capacitor banks.
- No penalty row does not mean no penalty. The charge is inside the units.
- The energy rate applies to the reactive component too, every month.
Derive the real power factor
Divide billed kWh by billed kVAh for the same month. That ratio is the average power factor the site actually ran at, and 1.00 is the upper limit for a purely real load. A site printing PF 1.00 can still have billed apparent energy that better correction would remove.
Twelve months of the derived ratio also expose swinging behaviour: a fixed capacitor bank that overshoots at light load and undershoots at full load.
- Derived PF = kWh / kVAh for the month.
- Track it across 12 months, not one, to see load-dependent swings.
- kVARh lag and lead rows, where printed, complete the diagnosis.
What correction is worth on kVAh billing
Improving the derived PF directly reduces billed kVAh units. If the bill gives kWh and kVAh, the hidden reactive-energy component is calculable as kVArh = sqrt(kVAh^2 - kWh^2).
The right fix depends on the diagnosis: adding fixed capacitors to an already over-corrected site makes things worse, and leading power factor has its own costs. An APFC with correctly sized switching stages usually beats a larger fixed bank.
- Under-corrected: add correction sized from the 12-month kVAr profile.
- Swinging fixed bank: convert to automatic switching before adding capacity.
- Over-corrected or leading: remove or restage; do not add more.
Related BillTrends pages
FAQ
My bill prints PF 1.00. Do I still have a power factor problem?
Possibly. On kVAh billing the printed PF is close to 1.00 by construction. Divide kWh by kVAh to derive the real average PF; if that ratio is materially below 1, reactive power is being billed inside your units.
Which DISCOMs use kVAh billing?
MSEDCL is the prominent example for HT and many LT industrial and commercial categories, and other state DISCOMs have been moving categories to kVAh billing through tariff orders. Check the billing-unit column on your own bill.
How does BillTrends handle kVAh bills?
It derives the real PF from billed kWh and kVAh, reads kVARh lag and lead where printed, classifies the site as under-corrected, swinging or over-corrected, and prices what the gap costs at your tariff, with each number traced to its bill line.