Correct, but via smart meters the utilities will end up charging us for a poor PF. Remember, the vast majority of household loads have terrible PF value since much of the connected devices are powered via poor quality switched mode power supplies.
Sorry, I am not sure what you are saying. Do you mean that smart meters do measure the instantaneous power correctly, so that the moment there is no difference between a smart meter and an analogue one, but at some point in the future we will be charged extra for a poor PF?
There is a lot of media advertising about the benefits of Smart Meters, that they allow any consumer to know exactly what they are spending on gaz and leccy. As advertised this is a no brainer, but for electric users it has a sting and likely much better margins for electric suppliers.
Power in Watts is measured by multiplying voltage by current which is simple and tells you e.g. how hot a heating element will get. But if you have mostly LED lights, capacitors, then voltage and current no longer give you power. Indeed it is possible with a capacitor to have both a high voltage and a high current and yet consume no Watts.
The reason being that the capacitor will take current to charge on half of the AC cycle and then return that current on the other half of the AC cycle, so that the net current consumed is zero.
All non-smart meters calculate real power, and as such LED lights are very low consumers.
But smart meters can be set to calculate not the real power, but VA 'apparent power', i.e. voltage times largest current. Such that the capacitor in an apparent power measurement will leave the consumer with a bill that would not exist with a standard meter.
You might argue that apparent power is not worth anything, but it is useful as it allows you to size cables correctly as in the capacitor example, the cables must be able to cope with the current coming in and then coming out and it is likely this argument that the electric suppliers will use to justify ramping up your bill, and if this happens it will be significant.
Under apparent power, what in real power would be a 2 watt led light would be billed as something like a 20 W light. Multiply that by a typical house of many led lights and one can see a big potential windfall, and that is why smart meters are generally free. The scope for profit margin expansion is substantial which is bad for consumers, but good for shareholders in electric suppliers.
The uncertainty is whether our politicians will let the suppliers use apparent power as a way to bill you. For the moment it looks like they will, albeit delayed, but it is likely going to become a very contentious issue.
As fas I can tell, the main rational for smart meters is so that the power companies get a nice new large-earner, and with these installed domestically, billing for apparent power for very little cost to them, hence much better margins.
Of course you could say how smart meters allow consumers to be able to see their minute by minute power consumption, but that is like setting your car to show instantaneous mpg, fun for a few minutes then largely ignored.
Smart meters also don't need meter readers or inspections, which is a plus; but it is the potential to charge domestic customers for apparent power that is the hidden gem for shareholders and hence why I'm resisting having one fitted since my house is filled with capacitive based switched mode power supplies.
No, I was Trained on this years ago.
Smart meters can tell you how much reactive power is generated from your energy supply. They display the difference between working power(reactive) and total power consumed.
As far as I am aware your bill should be what is displayed on meter if domestic, industrial will be charged more if their power factor is over a certain limit.
Electricity billing in the UK - Wikipedia see reactive power
@dougle03 so I think you are saying yes to my suggestion which was that smart meters do measure the instantaneous power correctly, so that at the moment there is no difference between a smart meter and an analogue one, but at some point in the future we may be charged extra for a poor PF.
Shouldn't that be below a certain limit?
Do you know what that limit typically is?
Well certainly my son's costs have dropped significantly since he got his as it has allowed him to use a tariff that is cheaper in the early morning, which is when he schedules his car to charge. It has had a less dramatic effect for me as I don't have an electric car yet.
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Depends which way you count, but you are correct
Varies(ask your supplier) Typically suppliers apply a power factor threshold of between 0.85 and 0.95, above which there is no charge
Question what happens when there are 30million (approx) cars charging,? plus new electric boilers as gas is going to be banned(except hydrogen)
P.S this is very off topic
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OK, thanks.
Indubitably.
Just seen this thread - let me offer the next lowest way other than native NR 
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Good one thanks !!
Craig
I am not sure what your background is - obviously some form of electrician i would imagine. However what you are saying about the average house having lots of devices with low PF is in this day and age getting to be rarer.
Industrial users can indeed have large power devices with wildly varying PFs and hence they get billed differently to home users.
Parasitic devices such as standby on TVs etc will have low PFs - but major devices such as Refrigerators (moderns one), Aircon, Pool pumps, heat pumps etc all have very high PFs - approaching 1 in most cases.
Craig
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