High energy usage in the early hours - what's the cause?

Hi @holliesavage ,

The most likely culprit I can think of is either water heating or central heating. Can you show us some screenshots of the usage data please?

My water heater doesn’t come on until 6am and goes off at 9am it’s on a timer and we don’t have central heating as we are an all electric flat so have those electric radiators but we don’t use them.

Hmm… That’s really weird…

I’ll have a think about this one and let you know. I’ll probably also grab a few friends too if that’s OK?

Amazing thank you any help would be appreciated! It’s just really strange and concerning as to why my usage is that high when we’re asleep! 

Something is happening at around 3.40am.

It’s using around 3kW constantly until morning.

This would tie in with the power of an immersion heater.

First thing I’d check is whether the time on the timer for the water heater is correct.

@holliesavage Looking at the log of use, you might have to do some detective work. As @nealmurphy mentions, the timer on the water heater is a prime suspect. Other than that, you may need to try turning off certain items to pick up what it is that’s consuming the power. 
Is there a point at which the power use goes back to ‘normal’?

Neal wrote:
This would tie in with the power of an immersion heater. First thing I’d check is whether the time on the timer for the water heater is correct.

I second this. There is an antidiluvian timer on the immersion heater here which is set on installation to be switched on for a few hours (five or six, I think) each night. The heater turns off when the thermostat tells it that the water is hot enough.

Its built-in clock has to be corrected after each power cut, and adjusted for summertime each year. So if you recently had some electrical work done (installing a smart meter, perhaps?) that involved switching off the power meanwhile, your timer is probably out by the amount of time the power was off for.

The on-hours are designed to be in the middle of the (7-hour) off-peak period, so if the clock does stop for a bit for whatever reason, the heater doesn’t operate out of off-peak hours when power is cheaper. This is probably irrelevant nowadays, if the primary heater is fed from a dedicated off-peak circuit which makes sure that the power-hungry things like water heaters and storage radiators just won’t heat during expensive hours. 

Yeah, usually a Smart Meter upgrade lasts for around an 30-60 minutes per meter for a simple straight swap, but it can take two hours in some cases.

I’d agree with the comments above. Either a single power cut (or several shorter ones!) might have knocked a timer out of sync because that’s the only logical explanation I can think of.

I’m still running through other scenarios too! I’ll let you know here if there’s any others I can come up with.

We had our smart meter fixed in august as it had stopped working and they came to fix it then I was with SSE at this time.

we haven’t had any power cuts that we know of or any major electrical work done either.

My water heater timer goes on at 6am and goes off at 9am that’s enough hot water for us for the day as we are an all electric flat we have a tank for our hot water and no central heating.

Firstly, @Firedog gets a like for brilliant use of the word antidiluvian!

In terms of power cuts, if it was an analogue clock and there was a power cut the timer would think that it was earlier than it actually was, so the heating would be coming on later than programmed. If digital it may have reset to midnight when the power was restored. So if power was restored at around 21:45, it could mean the timer was running 2hrs 15mins fast and sticking the heating on at 03:45 thinking it was actually 06:00.