What's causing electricity spike during the night?

[sunshinyday80]

I've recently downloaded an app which shows smart meter data by the hour, and I'm quite surprised to see relatively large spikes of electricity use at strange hours (randomly between 10.30pm and 3am, so it's not the daily standing charge being added on). Can anyone help me work out what's causing it? It doesn't happen every night so there doesn't seem to be a pattern to it. We haven't got a hot water tank, no laundry done overnight. Only devices are a couple of phones being charged. Any ideas what it could be?

Fridge/freezer?

Teenager gaming?

I read somewhere someone had a similar problem, they re-set up the meter and it went away.

Check the actual meter reading before 10:30 and in the morning to see if the actual readings support what the smart meter is saying, apparently they can be a bit dodgy.

I did wonder about the fridge freezer, but it's a higher spike than we ever get during the day, and sometimes it's several times in one night and other times we don't get any spikes at all. Thought maybe a fridge freezer would be a bit more consistent usage through the day and night.

No teenagers gaming, everyone in the home is asleep when these spikes are happening. They are higher than times when we're cooking, lights on, washing machine/tumble dryer on, tv on etc.

That's a good idea thank you, we'll try that and see if it can shed some light on what's happening

Do you have outside lights on sensors that are coming on, sometimes they are very high wattage?

Front security sensor that comes on briefly, but thought it would be highly unlikely to use 1kWh in a one hour period. There are no spikes at times when we know the outside light is coming on frequently in the early evening when we go out/come home.

Do you have devices on standby such as Xbox, Sky / Virgin box etc that might be running automatic updates?

Also, if you have a combi boiler (like we do), they do tick on occasionally at night even if heating or hot water is not running, just to keep the system primed, I think.

How large are we talking?

It's about 1kWh in a 30-60 minute period, roughly 10-12% of our daily total usage. So it's not huge in the grand scheme of things, but is still more than we use in early evening when lights on, cooking, tv on all at the same time.

Everyone charging devices overnight?

We charge 2x iphones every night, no other devices on charge. The spikes are not consistent though, some nights no spikes, others one spike, and others 3-4 spikes. If it was devices charging it would be regular and consistent every night. Plus an iphone charging would only use 3% of 1kWh.

You'd have to be charging about 200 phones for it to be due to them.

You don't have a neighbour plugging their electric car into one of your external plug sockets do you??

1 kW is about 4A (amps).

Quite a lot for any single device that isn't associated with heating of some kind.

I'm surprised you use less than that for cooking/lighting/tv watching. Cookers are normally hooked up to 30A sockets (although they don't use anywhere near this all the time, but 10A+ wouldn't be unusual on start up).

Sounds like the kind of use associated with an electric heater or pump of some kind. Feels like too much to be a fridge.

The fact that it comes on randomly and only at night seems to imply some sort of temperature dependence.

It could be your boiler kicking in on frost protection, but the usage seems pretty high for that - I would be surprised if this was more that a couple of hundred W.

I've not looked recently, but our daily standing charge used to appear on our smart meter some time between 2-6am. Other candidates might be self-defrosting fridges/freezers cooling down after defrosting perhaps?

Have you got a "frost free" freezer? These use heating coils to defrost the build up of ice.

I did wonder about it being the daily standing charge, however it does not happen every night. We have no electric heaters or pumps in the house so it can't be that. Definitely no electric vehicles as no outside sockets (and no neighbours with electric cars). I'm wondering if it might be the fridge/freezer - it's only a few months old but I wouldn't expect it to use 30% of our daily electricity usage, does that seem right?

To give a bit more info, 3 nights ago we used 3.63kWh between the hours of 11pm and 3am, the night before that 0.64 kWh over the same period. Our peak use during the day is between 5.30-7pm and that's coming in at 2.02kWh for cooking, lights, tv, etc. It doesn't make sense to be using so much more when we're all asleep and nothing is switched on.

Have any neighbours an electric car?

I'd check the timer for my boiler or Emerson heater?

Ours recently re set its self as we had a power cut and it put the comfort option back on our boiler which keeps the hotwater at a certain temp 24/7 😱

And the heating timer had reset its self to constant as well!

No electric cars near us (and no outdoor power sockets either). No immersion heaters. Boiler won't be on in the night and neither will the hot water - but surely those would use gas anyway?

It is a lot for a fridge. I have just purchased an E rated fridge and it is rated at 230 kWh per year. That is less than 1 kWh per day.

Unless you have a giant fridge or something...

Are you in an appartment or an older house ? Sometimes when appartments get converted the electricity wiring gets "confused" and it is quite common that on appartment ends up paying for anothers electricity.

Another possibility is stuff like garages. When outside buildings get wired up they sometimes get wired into the wrong supply. But this doesn't really explain the odd hours.

I guess two more things you could try. One is to check the meter (not the smart meter) before and after each evening to check that the electricity really is being used and it isn't some sort of smart meter glitch or the smart meter catching up. You said earlier you would do this but no confirmation.

Our boiler automatically heats a small amount of water inside it so water arrives at the taps quicker. Personally, I can't tell the difference so we set the eco option (Worcester Bosch). If you've got this on your boiler, might be that's coming on. If not, are you in the north where it's cooler. Some boilers have a setting to run if temperature falls below a certain level, and that's more like to happen in a colder area.

End of a long dishwasher cycle? Ours is >3 hours and the energy usage peaks at the end when it’s heating to dry.

Did this ever get resolved? My smart meter says that we are using £1 every night, (very consistent), between midnight and 7am. We average around £2.50 a day, so more than a third of our usage is when we are asleep. I’ve switched off certain plugs to try and identify the issue, such as the NAV, modem, TVs and boxes etc. It is very frustrating. I just wondered if you’d found out what had caused your spikes?

@JoDec61 I think the standing charge is likely to come off during those hours. Do you have fridges or freezers in a garage? We suspect that’s our main overnight culprit.

Tagging the OP, @sunshinyday80.