Domestic electricity - inexplicable increase in usage

[slope]

Snowdon Towers' domestic leccy usage has increased alarmingly since the end of October 2020. But I can't think why - as far as I can tell/feel nothing has changed with regard lifestyle or appliances. Annual usage has been consistent for the last 10 years+ at around ~1300-1400 kWh per annum.

30 Aug - 19 Nov 2021 usage went up by 34% from 321 kWh - 431 kWh (compared to same period previous year)

20 Nov - 08 Feb 21/22 usage went up by 92% from 327 kWh - 628 kWh (compared to same period previous year)

Any suggestions how one sleuths this? (non smart metering)

[rogerzilla]

Were any of those meter readings estimates?

Is there a Vietnamese chap in your basement running a cannabis farm?

[slope]

No, they were my own readings.

No, the chap downstairs is English and wants to join the fuzz!

[Kim]

30 Aug - 19 Nov 2021 usage went up by 34% from 321 kWh - 431 kWh (compared to same period previous year)

20 Nov - 08 Feb 21/22 usage went up by 92% from 327 kWh - 628 kWh (compared to same period previous year)

That's an increase of 57W and 157W respectively.  More than a couple of light bulbs, less than a cannabis farm.

Any suggestions how one sleuths this? (non smart metering)

Plug-in power meter.

Prime suspect would be fridges/freezers.  Sticky thermostat or leaky insulation.

[Lightning Phil]

The Christmas light display you had running over winter?

[mrcharly-YHT]

The tumble drier that you are using a lot more in winter?

[slope]

List of appliances (which hasn't changed for years)

1. Small fridge/freezer 162l/44l
2. Bosch A rated washing machine - no tumble drier
3. TV modern LG (hardly ever used)
4. iMac
5. iPad
6. BT Router
7. BT FTTP broadband box thingy
8. Printer
9. Kettle
10. Illy coffee pod machine
11. Electric hob and oven (recent new)
12. CH pump (Combi oil burner)
13. LED lighting throughout

[Kim]

Assuming no change of your habits, I'd suspect the fridge/freezer, the TV, the iMac and the coffee pod machine and maybe the CH pump as things that might use a substantial amount of power without you being aware of it.

Router/modem, iPad and printer are unlikely to be able to draw enough power to make that big a dent in your electricity bill.

Washing machine, kettle and cooker can all use loads of power, but for short periods that you're going to be aware of.

[FifeingEejit]

List of appliances (which hasn't changed for years)

1. Small fridge/freezer 162l/44l - Getting less efficient with age?
2. Bosch A rated washing machine - Getting less efficient with age?
3. TV modern LG (hardly ever used)
4. iMac
5. iPad
6. BT Router
7. BT FTTP broadband box thingy
8. Printer
9. Kettle
10. Illy coffee pod machine
11. Electric hob and oven (recent new) - Are you cooking more or has this got a higher rated element than the previous but then you'd be burning stuff and same goes for if the thermostat is miles off.
12. CH pump (Combi oil burner) - Getting less efficient with age?
13. LED lighting throughout

[woollypigs]

Our old fridge freezer that we used mainly for extra freezer space. "Freaked out" and started to drain leccy as it generated heat instead of brrrr. So check things plugged in to see if they are in good health.

[Quisling]

I'd also suspect the fridge freezer as being a possible culprit.  How old is it?  If it's newish then I doubt it would normally use more than 1-2 kWh/day.  A really old one might use double that.  Ditto, if a newer one had leaked some refrigerant it might be having to work a lot harder than normal.

Do you have an electric immersion heater?  These sometimes fail to "on" though it's pretty rare, and if it did then being constantly on would probably cause a greater increase in demand than you've observed.

The increase in kWh in each period is greater in the winter months, which means either
1. the problem didn't manifest itself until later in the summer period,
2. the problem relates to equipment that is used in the heating season (fan heater etc.), or

Do you have a smart meter and if so can you obtain daily (or even weekly) meter readings from your supplier?  If so then we could do a degree day regression analysis and see if the cause is related to space heating demand.

I'm not sure how fancy your coffee machine is but some of them can drink electrons while sitting idle, see:
https://www.wholelattelove.com/blogs/tech-tips/espresso-machine-energy-usage-and-cost

[Kim]

Our old fridge freezer that we used mainly for extra freezer space. "Freaked out" and started to drain leccy as it generated heat instead of brrrr. So check things plugged in to see if they are in good health.

Ours developed a 'sticky' thermostat: It would sometimes get stuck 'on' for a day or so, before reverting to normal operation, which wasn't immediately obvious other than through monitoring of temperature and electricity consumption.  You might notice items in the fridge were a bit colder than usual if you were paying attention, but -28C doesn't feel much different to -18C.

Easily fixed with a new thermostat module.

[hellymedic]

I suspect the cooker…

Kettles only run for a few minutes but hobs and oven are another matter.

Ou dehumidifiers and computers rack up a fair bit, as do the electric heaters in the sheds if D uses these.

[Kim]

I suspect the cooker…

How would a cooker use substantially more power if the user's cooking habits haven't changed?

Dodgy thermostat would likely result in undercooked/overcooked food, and get noticed.  Oven door failing to seal is a possibility, I suppose.

I can't imagine much that would change the efficiency of a hob, where they spend most of their time turned down to simmer.

Grills run flat out, and would be subject to variation in supply voltage (see also: electric showers).  But how much grilling does someone do?

[slope]

Thanks for all the replies and foods for thought 

I've ordered a plug in power meter.

As mentioned, the overall power consumption has hardly varied over the last 10 years or so If anything it's reduced. Perusing past bills, the usage closely mirrors the fluctuating quarterly/seasonal use - until last autumn and now almost doubled between 20th November and 8th February.

The oil fired CH boiler is a condensing combi, so no immersion heater. It was newly fitted in 2014.

The electric glass top not induction hob and a cheapo oven were new just less than a year ago. The small fridge/freezer is about 4 years old, but it's only a cheapy - and it is well overdue a defrost

No smart metery hereabouts cos no mobile phone signal.

(which has just brought a completely new issue re the copper phone line being cut off next Monday, so as to utilise the FTTP connection - BUT means in the event of a powercut, we won't be able to contact emergency services. BT's work around is a limited battery back up unit, which are out of stock due to global supply issues, or some such?)

[Paul H]

Faulty meter?  Apparently it's rare but not unheard of.

[wajcgac]

The increase in kWh in each period is greater in the winter months, which means either
1. the problem didn't manifest itself until later in the summer period,
2. the problem relates to equipment that is used in the heating season (fan heater etc.), or

As it looks like it could be winter related I thought it might be possible that the CH pump has been switched to, or is now on a higher setting for some reason.

However I've looked at the manufacturer data on a typical Grundfos CH pump and it seems that the lowest setting uses 25W and the highest 50W approx. Even if you were now on the higher setting (rather than the lowest) and running the pump 24hrs a day it would only add 0.6KW per day to your usage (assuming there is not some failure mode where it keeps running but uses vasts amount of energy)

Looking at your figures below it would suggest you are seeing an increase of approx 1.4KW to 3.75KW per day depending on the period.

Not much help I guess other than to potentially rule out the CH pump.

30 Aug - 19 Nov 2021 usage went up by 34% from 321 kWh - 431 kWh (compared to same period previous year)

20 Nov - 08 Feb 21/22 usage went up by 92% from 327 kWh - 628 kWh (compared to same period previous year)
 (non smart metering)

[Kim]

Faulty meter?  Apparently it's rare but not unheard of.

If the plug-in meter doesn't reveal a likely culprit, that's certainly worth investigating.

[Diver300]

Faulty meter?  Apparently it's rare but not unheard of.

If the plug-in meter doesn't reveal a likely culprit, that's certainly worth investigating.

A plug-in meter may help you check the suppliers electricity meter.

[Pickled Onion]

Without wanting to go to Kim-style lengths to constantly monitor, I read the meters every week and put the numbers in a spreadsheet. I have a notification on my phone to remind me to do it. It takes a few minutes and is the result is generally really boring, same numbers each week, gas follows the weather. It does show that heating the house to silly temperature over Chrimbo when family + baby visited wasn't breaking the bank. It will give a timely heads up if anything suddenly starts to use more than it should. Like when the heating timer heated the kitchen at 0500 every weekday the first winter of WFH. Oops.

[slope]

Here's the last 3 year comparison graph from Scottish Power.

I've never been one to begin to believe in how graphs (and politicians etc) can be manipulated/misrepresented. Mainly because I don't understand or will relate to such 'things'

Does this help??? Or confuse?

[perpetual dan]

Did your habits change at all with the various lockdowns and surrounding working from home? We certainly are at home more, so two more laptops, extra coffee, lights on longer, sometimes cooked lunch, a bit more heating so the fridge working a bit more to keep it cool. That’s probably a bigger rise than you’re seeing.

[Speshact]

Vacuum Cleaner? Power shower?

[ian]

Sentient mains-powered sex toy?

[slope]

Not knowingly nor realised changes in domestic routine for several years+retired. Certainly a creature of great habit (needs must). Bad back/excuses/laziness prevents Hoovering more than once a month. Sex toys? Wot like leccy toothbrushes? Nah, not yet

Which reminds me ^ian^ of a cryptic crossword clue today in the Indie:

"Nobody stop Ian describing the worst of all worlds" (8 letters)