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Electricity consumers are divided into domestic, commercial, industrial , etc based on the power factor. Domestic loads are mainly resistive. But not 100% resistive always. The industrial meters shows the power factor. The tariff changes if the power factor drops below a specific range.

Won't it be better if all meters measured power consumption in KVA and all consumers have to pay for total KVA consumption?

Or there is more advantage in the KWh tariff?

Sadat Rafi
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    Probably something really simple like: residential users like having less numbers to worry about. Or: old residential meters aren't capable of measuring kVA and they don't want to replace them all. – user253751 Jun 18 '20 at 13:08
  • @user253751 Isn't KVA super simple to measure compared to kW though? It almost does seem like the power company is going out of its way to measure kW for residential. – DKNguyen Jun 18 '20 at 13:15
  • How would you account for those people who have solar set-ups who sell kWh back to the grid? – Andy aka Jun 18 '20 at 13:16
  • @DKNguyen It doesn't matter how hard it is to measure, it matters whether the existing meters measure it – user253751 Jun 18 '20 at 13:18
  • @user253751 You're the one who brought up "old residential meters aren't capable of measuring kVA" – DKNguyen Jun 18 '20 at 13:20
  • @DKNguyen yes? They don't have a knob you can turn to switch between kVA mode and kW mode – user253751 Jun 18 '20 at 13:20
  • In our region all meters are gradually replaced by prepaid smart meter. And no one is allowed to use old analog meters. Cost of meter replacement has to be carried by the consumers. I guess in digital devices it should be easy to measure KVA. – Sadat Rafi Jun 18 '20 at 13:21
  • @user253751 It's tautological reasoning because it doesn't address why the meters are that way to begin with. It is essentially saying that they are what they are because that's the way they have always been. – DKNguyen Jun 18 '20 at 13:22
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    @DKNguyen, the old meter design goes back to when residential loads were almost entirely lighting and heating, so power factor was very near 1. Presumably kWh was actually easier to measure than kVA at the time, or they would have been measuring kVA all along. – The Photon Jun 18 '20 at 14:51
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    I am voting to close this question as opinion based. It also mostly about market forces. Kilowatt-hours are a measure of energy. There will always be a strong bias towards paying for energy based on actual energy used even though the distinction between energy, current and power is not universally understood. KVA charges are about suppliers charging for additional costs of delivering energy. That can be explained to larger businesses that employ facilities managers that can understand the concept. –  Jun 18 '20 at 14:57
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    The very first electrical consumption meters measured ampere-hours, directly proportional to KVA-hours. Since very early history of electric energy consumption metering, methods of measuring kW, kVA, and kVA reactive and integrating them over time have been easily available. It is a little more complex to measure and record two or more quantities, but that has been done for a long time. –  Jun 18 '20 at 15:10
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    A kWh is also a relatively convenient unit that can be used across different energy sources, gas bills (in some countries) show kWh as the volume recorded gets converted to kWh then it is easy to compare heating power etc – Solar Mike Jun 18 '20 at 17:19
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    @Sadat, you have 'KVA' in your question title and post. That reads as kelvin-volt-amperes. You need a small 'k' for 'kVA'. Capitals matter. – Transistor Jun 18 '20 at 17:28

1 Answers1

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The advantage of billing in kWh is that it reflects actual (real) power used by the consumer. Of the alternatives (kVA, Ah, etc.) it's the most fair.

Large industrial users with reactive loads pay a penalty if their power factors are too low, so this encourages them to invest in power-factor correction at their infeed side.

Lately, this is also the case in consumer: switchmode power supplies of 75W or more need to have power factor correction in them (EU Directive EN61000-3-2).

Related question: Why is electricity consumption billed in watts and not amperes?

hacktastical
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