Gas use for a 10 minute shower

Jolaaled

Hi all. How much gas on average is used for a combi boiler shower lasting approx 10 mins? 
My Octopus usage (via my new smart meter), says, over 7000. How is this possible?.

[Deleted User]

Clearly, something went amiss with the meter readings during that time, that is enough energy to boil 2 road tankers full of water.

RoseBerni

I have no idea 
but at the moment I’m putting on £6 a week on my gas - pre pay meter 
almost £4 of that is the standing charge 
3 adults in the house and we all shower twice a day 
normally in the shower 5 mins each time but longer for me if im washing my hair 

matelodave

A combi boiler flogs its heart out every time you turn on the tap until it's settled down. A lot will depend on what sort of shower you have, the temperature you've set it to and the flow rate although it's impossible to use 7500kwh.in ten minutes.Thats around 50% of most people's annual consumption

Most combis are rated at somewhere between 24-30kw so even at full tilt it should only consume around 4-5 kwh for a ten minute shower, probably a lot less I'm guessing that the graph you've posted is an anomaly. You really need to check what the meter is showing rather than what you are seeing above and do a bit of monitoring if you think there's something awry. Makes sure your bills are accurately reflecting your meter readings.

However that said, some showers can dump 10-15 litres or more a minute whereas an eco shower head will reduce that to 6 lpm. Thats a difference of possibly heating 150 litres compared with 60 litres for a ten minute shower.

Reduce it to five minutes and you could save 50% of the energy and 50% of the water. You could also reduce the temperature of the water from the boiler which would also save energy by helping the boiler work at it's optimum

Spoonie_Turtle

Isn't there some firmware issue with some gas meters?  A few other posters here with Octopus have encountered impossibly high gas usage recorded.

michaels

RoseBerni said:

I have no idea 
but at the moment I’m putting on £6 a week on my gas - pre pay meter 
almost £4 of that is the standing charge 
3 adults in the house and we all shower twice a day 
normally in the shower 5 mins each time but longer for me if im washing my hair 

Is that about 25 units a week?  6 showers per day x 7 days per week x 70 litres per shower means you can only heat the water up by about 8 degrees using 25kwh - so say from 12 degrees to 20 degrees - brrrr

Ultrasonic

The number on the graph is clearly nonsense! If you want to know how much gas your shower actually used then read your actual meter before and after the shower and calculate the difference (and do when gas isn't being used for anything else). You'd then need to convert the volume to kWh. Your last bill will probably include the equation you need to do this.

Ms_Chocaholic

Do you need a 10 minute shower?

ab1234567890abcdefgh

Those segments are clearly not hourly segments.

I'd finger in the air put them at half hourly segments, so it shows you used 7.5kWh in half an hour,

Using a 30kWh boiler at full tilt for 10 minutes will use 5kWh of gas. If yours is bigger than that, that might explain why it used 7.5.

As Ms_Chocaholic says, do you really need to shower for 10 minutes?  That's an awfully long time, I'd die of boredom standing in a shower for that long.

The_Fat_Controller

My showers of around 5 minutes use 2 kWh +/- 10% depending on how hot I have it.

30 kW Worcester combi boiler, no preheat used.

wrf12345

So 75p for a ten minute shower at the new capped rates? Electric shower seems a touch cheaper then, depending on kw of the shower? Just thinking, may be close to the stage where on-demand hot water is cheaper using electric than gas (and a lot cheaper using a heat pump), just thoughts for my next house renovation where am tempted to go for a wood burner for heating and all electric otherwise (personally don't use any hot water myself but won't go down well with estate agents if I ever want to sell).