Smart meter showing huge, silent spike

shelford1975

Every so often I notice this insane spike in the amount of electricity being consumed in my house, a typical example of which is shown here. This was last night, and the only things actively running were the WiFi hub, the clock on the cooker and the fridge freezer, and my baseline consumption with just these three is 30w. However, the house was completely silent. If it was the fridge, I'd have expected some noise. When it's cooling or defrosting, it the draw goes up to about 103w. What the bloody hell is going on? Is this a normal thing that "just happens"? It's obviously adding quite significantly to the bills, even if it only lasts for a minute or two.

Dimanche_Prochain

IHD's are not known for being particularly accurate, the only thing you could do is to turn everything off and see if it still happens.  If it doesn't, leave one thing plugged in at a time until you figure out what the offending device is.

However 3kWh is space heater level of energy usage, so it's far more likely to be a glitch with the IHD.

Incidentally one or two minutes at that level will cost you about 1.5-3p, so if it's happening infrequently it won't make much of a difference to your bills.  Once a day would cost you 45-90p a month.

ctdctd

Is it the transient spike when the compressor on the fridge cuts in?

If it is, it should only last for well under a second and have minimal impact on your actual consumption.

QrizB

It could just be the IHD catching up after a period of loss of signal. Mine does that occasionally.

km1500

The only way to tell for sure is as soon as you see it, turn your consumer unit switches off one by one - this will show you which circuit is drawing the power. 

You might have to do just a couple of switches per occurrence if you only have a short time

[Deleted User]

It is worth raising the issue with the supplier. Smart meters can meter/detect reactive loads. 

There was an issue a couple of years ago when multiple consumers detected a problem with a certain model of meter and battery. Both items were within the stated technical specifications; however, they didn’t play nicely together. My supplier changed my SMETS2 meter which resolved the problem. 

FreeBear

The IHD will not give you a decent granularity of the power usage to be able to pin down exactly what is causing the surge. I capture power consumption at 30 second intervals (via a separate energy monitor), and get the occasional spikes being recorded. Judging by the location in relation to an overall jump in consumption, it appears to be caused by a fridge or freezer switching on. Quite likely that the actual spike is no more than a second in duration, and just appears to be longer due to the frequency of data capture.