The “how much does this cost to run” thread?

[AtomicBlondeRose]

Based on posts about people thinking of using candles instead of electric lights - which is both dangerous and not likely to save any money, I’d like to set this thread up as a place where people can ask how much items in their house cost to run, to let posters make informed decisions about whether or not to keep using them after energy price rises.

If you want to ask, useful information to have is: the energy usage of the item - eg a heater might say on it that it’s 1000w. If you don’t know that the name/model number as accurately as possible. Also to give you a useful estimate it would be good to know your current gas/electricity price tariff price per unit. However it’s easy enough to work out at current and predicted price cap levels.

I can’t promise to answer everything so please can I call upon other numerate MNers to help out? I think this could be a real lifesaver.

247kwh isn't a lot for a 4 bed house. I think the average for a 3 bed is supposed to be about 5000kwh a year, or averaged out to 400 per month. So you weren't far off before.

Obviously lower is better but there are diminishing returns. 380kwh a year for a fridge/freezer is better than lots of old ones people will run. A++ ones these days will be 250kwh a year so only 10kwh a month saving but £600+ for a new fridge. Just bear in mind to buy efficient when they're due to be replaced and that should be enough.

if you have an immersion don't leave it on 24/7 (I know you say you don't so thats good). Overnight tariff if you have one for heating it up and then perhaps a blip in the evening when people use the hot water

Go through your big stuff and put power monitors on and measure for a week and build up a picture of your usage. Maybe a pie chart can help (even sketched) to give some context. Likely your big ones will be oven/dryer/washing machine/dishwasher/fridge. And then your 'AV' like TV/amp/consoles all piled together might be another slice. Standy devices probably barely register.

That can help you decide what is unavoidable to use and can't get cost down, unavoidable but current device is inefficient and could make reasonable saving to replace, and 'we can get this down with some behaviour changes like turning off overnight with a timer plug etc'

also worth projecting your costs/savings across a full year to amplify them - saving £5 a month might not seem a lot but £60 a month might wake you up. And try a few different tariffs. If you're already on a fix at eg 20p/unit the savings may not look worth it, but estimate the costs at the october cap of 52p, and try another at 75p (just in case). May be worth making changes now while you're on a cheaper tariff to blunt some of the impact when prices go up

I took a measure on the gas before they started their showers, and again after. I worked out my showers (at 12p/kwh) currently cost 6p, my son 7p, my wife 18p and my daughter 27p !

when prices go up to 15p/kwh I'm tempted to set a price cap allowance for showers and charge them a penalty if they go over 20-25p per shower. £1 fee should speed them up. They do have long hair though so I'll use my wife's time as a reasonable baseline.

there was a government report I read a few days ago looking into 'grid balancing' and how perhaps you could reduce peaks by smart devices, like the grid asking fridges to hold off on a cooling cycle for 30 minutes at high demand times.

In that they measured a bunch of houses and the average baseload was around 220-240w. Thats in line with mine so that is reassuring, but also 250w baseload 24/7 is 6kwh a day or 2200kwh a year which is a lot! (£1000 at 50p/kwh)

so halving that can save a lot. Trouble is thats with lights off etc so its things in standby, fridge, smart stuff like alexa/hue lights (which are always on using power to listen to commands), cable/satellite box which can use 20-30w

its also a more difficult one to trim down without doing a proper audit and monitoring devices over time.

Thanks MrKlaw. I've just been having the conversation about putting extra aside ready for my fix to end as the difference between what I'm on and the Oct price cap is frightening. I'm a very low user anyway and I've worked out a few ways I can save a little more, but it's a drop in the ocean.

It's a fairly simple calculation to add up your power consumption per appliance. I have done it for our rather high usage of 7200kWh/year. I just estimated hours per day, winter and summer and totalled them up. Adjusted the fridge to match the manufacturer's figure. It does help you focus on the big consumption items. I've already got a cheap tabletop grill to reduce using the oven for just one fish portion, etc.
One morning I did turn everything I could find off, even the fridge, all the routers, and could not get the smart meter below abou 100W. So I'm not sure if the "baseload" is right, but it still shows where to target effort.

I don’t think there is a simple calculation actually. I may know how many w my washing machine is but it doesn’t run at max watts the whole time. I watch my smart meter when using the washing machine and sometimes it’s using 2p per hour and sometimes it’s over £1 an hour and it’s constantly fluctuating to various points between the extremes.

which is why you need to either use the manual to get a 'per load' estimate or measure it (from a meter, taking away background load, or from a smart plug). That should let you do things like 'eco cottons wash = 1.4kwh, dark synthetics = 1.1kwh, tumble dry cottons = 3kwh' etc. And then estimate forward based on what you do per month and how your behaviour changes might be able to influence it

True but appliances like washing machines usually tell you the kWh of one cycle or the annual use (for 220 cycles) so you can check you've pitched it about right.

Just done this month and 500khw

i know some of that is spa

that will go off be end of sept

Great thread

Is it just me that finds the whole thing confusing? How do you know how much energy you are using and calculate how much it'll cost?
I don't have a smart meter, so do I have to check the meter ( outside)?

Sorry for all the questions!

Yup the meter.
You can see your use and guesstimate your future too. Plus giving them readings makes it accurate and not just estimaes which can vary eidely from reality

To find out the total electricity you use, read your metres every month.

e.g. Month 1 reading: 00100
Month 2 reading: 00200
That shows you used 100kwh in a month.

Then check your current pricing.
e.g. 30p per kwh
So 100 kwh x 30p = £30.00 a month

Then add on the standing charge you are currently paying
e.g. 50p a day standing charge
30 days x 50p = £15.00 a month

Total so far £45.00 a month.

Then add 5% on for VAT

£45.00 * 1.05 = £47.25 total cost

Gas is more complicated because you often first have to convert cubmic metres of gas into kwh (many metres how cubic metres!).

e.g. Month 1 reading: 00500
Month 2 reading: 00550
That shows you used 50 cubic metres of gas in the month. To convert to kwh I use cubic metres x 1.0264 x 39.1 / 3.6 but you can just use a tool like this one: utilitiessavings.co.uk/gas-kwh-conversion-tool/

Then you do the same maths as above but using your gas standing charges and price per kwh. And still add 5% VAT on the end.

Thanks for the replies.
I'm still totally confused! I'm with bulb so I'm going to request a smart meter which I hope will help.

As I said on another thread, don't over think it. If you can do shopping, keep track if what's in your cupboards and bank account, you can easily do this. Just don't overthink it😁 Then people get turned around

@Bubblebubblebah

Thankyou!

My heat pump dryer says it uses 1.91kWh for a full load. Is that really bad?

That's about 50p at the current svr of 27p.

Good or bad depends on whether you think it's worth 50p.

Can I just check my calculations please? My fridge freezer uses 280kw/h over a year. So, to get a daily figure if unit charge is 37.2p kw/h its -
280 x 37.2 = 10,416p over the year
10,416/365 to get daily charge = 28.5p

I have ordered a smart plug so will spend the next few days plugging various things in, it's a bit addictive

280/365 - 0.76 (kwh day)
0.76 x 0.372 - 0.285 - 28.5p
Yup

Thanks, I’ve never really understood the energy rating letters, so at least I know now how to work out coatings. @Bubblebubblebah you’re a star

Glad to help. I really think lots of people overthink it because they keep hearing how difficult it is! Once you look at it and count it once, it's quite logical 😁

Hi, I wonder if you could all help me with something. I bought a smart plug yesterday for my very old fridge freezer. It is showing in the last 24 hours that it has used 3.4kwh

Am I right in thinking I need a new fridge freezer 🙄

Looks like it!