kVAh Billing vs kWh Billing: Why Your Units Do Not Match Your Meter

What is the difference between kWh and kVAh?

kWh (kilowatt-hour) is active energy. It is the energy that does work in your plant — turning motors, heating furnaces, lighting the floor.

kVAh (kilovolt-ampere-hour) is apparent energy. It is the total energy the supply system had to carry to deliver that active energy, including the reactive component that flows back and forth without doing work.

Apparent energy is always greater than or equal to active energy. The gap between them is power factor. A plant with a power factor of 1.0 has no gap at all; every plant below 1.0 has one.

How is kVAh calculated from kWh?

Over a period in which power factor is steady, the relationship is a single division:

kVAh = kWh ÷ power factor

Stated the other way, for the same interval, kVAh is the combination of active and reactive energy: kVAh = √(kWh² + kVArh²). Meters record both, which is why your bill can show kWh, kVArh and kVAh side by side.

What does a low power factor cost on a kVAh bill?

A worked example, using round numbers so the arithmetic is easy to follow on your own bill. Take a plant consuming 100,000 kWh of active energy in a month.

At a power factor of 0.85, the plant is billed for 17,647 units it did not consume as active energy. That is 17.6% more units on the energy charge, every month, for as long as the power factor stays there. Multiply the extra units by your own energy rate to get the rupee figure for your plant.

Why did my state move from kWh to kVAh billing?

kVAh billing charges a consumer for what the network actually had to supply, rather than only for the part that did useful work. It also removes the need for a separate power factor penalty line, because the cost of poor power factor is already inside the units.

In Maharashtra, low-tension consumers above 20 kW moved to kVAh billing with effect from 1 April 2025, under the Maharashtra Electricity Regulatory Commission’s order in Case No. 217 of 2024. For those consumers, power factor stopped being a penalty line and became a direct multiplier on the units billed.

Billing basis is set state by state, and category by category within a state. Check the tariff schedule that applies to your own connection before assuming your state does the same — a figure from one state’s order does not carry to another.

How do I check this on my own bill?

1. Find the units block. If it shows kVAh anywhere as the billed quantity, you are on kVAh billing.
2. Find both kWh and kVAh if the bill prints them. Divide kWh by kVAh. That number is your average power factor for the month.
3. Subtract kWh from kVAh. That is the number of units you were billed for beyond the active energy consumed.
4. Multiply that difference by your energy rate per unit. That is what power factor cost you last month, in rupees.
5. Repeat for four consecutive bills. A steady gap is a standing condition worth correcting. A gap that appeared suddenly points at something that changed on the floor.

What this page does not say

• It does not tell you what correction equipment you need, or what it should cost. That depends on the measurement, not on an article.
• It does not quote a saving. We do not publish a savings figure for a plant we have not measured.
• It does not carry any one state’s tariff rates. The worked example above uses round numbers chosen for arithmetic, not rates from any order.

Related

Power factor is one of three charges on an Indian commercial and industrial bill that the bill itself never explains. The other two are the demand charge and time-of-day pricing. See how the three fit together.