How much gas should we use

mikemaple

Hi,

We like many i suspect are on a bit of an economy drive - and my wife has been keeping an eye on our usage. She is a bit alarmed at our gas usage - but I've no idea on how to tell if we are using about the right amount (as she is worried we are using too much).

I've just done a test today - heating set to 20, heating a three bed house with 11 radiators on, Baxi 51/3RS and in an hour on out ft3 meter we seem to be using (No hot water or cooking).

Results are reading from meter :-

start 0889.46
+1hr 0889.93
+2hr 0890.21
+3hr 0890.51

Does anyone know if that is too much, or about right ?

rogerblack

Looking at the later readings, it seems to have settled down at about .3/hour.
This is 30 cubic feet an hour.
A hundred cubic feet is about 30kWh, this means that you're using ~10kW, 10 units an hour.
Over a 24 hour period, you will use 240kWh.
If you are paying 4p/unit, that is about 10 quid a day.

However.
In the initial few hours, the house may still be warming up.
You really need to run it for an entire day.
Then look at the difference between in and out.
If over that day, it averaged 5C, and it was 25C inside, then the difference is 20C. If it got down to -5C (averaged over the day), the difference would be 30C, and the usage would go up by half.

Find your bill.
Work out your unit rates.

Pincher

Assume one imperial unit = 31kWh.

0890.51 - 0889.46 = 1.05 imperial unit.

So, you used 1.05 x 31 = 32.55 kWh

Assume Gas Tier 2 rate is 3.5p

3.5p x 32.55 = £1.14

That is all the maths you need to know.
Just substitute your own numbers.

MillicentBystander

We have a quite large-ish 4 bedroom/2 bathroom semi and we used 11000kWh last year but we've since had cavity wall insulation installed and the difference in how quickly the house not only heats up but for how long it stays at the desired temperature even when the heating goes off has greatly impressed us. i'm looking at no more than 10000kWh this year. Another thing is do not heat the rooms that are not regularly used as much as the rooms that are (TVRs on the radiators are another easily recouped investment). Seems like common sense but they say common sense is not that common Which probably explains why plumbers invariably place the CH thermostat in the coldest room in the house - the hall. Stupid. Gone are the days when we could wear shorts/t shirts in the house in the Winter, i'm afraid.

Pincher

mikemaple wrote: »

We like many i suspect are on a bit of an economy drive - and my wife has been keeping an eye on our usage. She is a bit alarmed at our gas usage - but I've no idea on how to tell if we are using about the right amount (as she is worried we are using too much).

A German superinsulated Passiv Haus does not need heating at all, so £0.

My house was very poorly insulated four years ago, using a 30 year old 75% efficient non-condensing boiler. Tier 2 rate was about 2.2p per kWh. Using £10 a day, the upstairs was still cold. For the same amount of gas, at 3.5p per kWh, I would be paying £15.90 a day now.

So, run your heating for 24 hours. If you spend

£5 on gas, congratulations.
£10, worry about insulation.
£15, huddle your wife for warmth, and curse the bleak winter that is to come.

mikemaple

Thanks all so far

At least no-one has said - oh my gawd that's a stupid amount you must be heating the whole street

FYI had the thermostat moved to the living room about 4 months ago and all rads have thermostatic value, walls have cavity insulation - but I do need to top up the loft - as it's done to the old levels.

Does cavitity need topping up ?

MillicentBystander

Pincher wrote: »

A German superinsulated Passiv Haus does not need heating at all, so £0.

My house was very poorly insulated four years ago, using a 30 year old 75% efficient non-condensing boiler. Tier 2 rate was about 2.2p per kWh. Using £10 a day, the upstairs was still cold. For the same amount of gas, at 3.5p per kWh, I would be paying £15.90 a day now.

So, run your heating for 24 hours. If you spend

£5 on gas, congratulations.
£10, worry about insulation.
£15, huddle your wife for warmth, and curse the bleak winter that is to come.

Have you been reading the Express as well? They've been predicting -20c for about 2 months now. I suppose the premise they work on is if thye keep saying it (and keep putting it on their bloody front page, interspersed with the other staple headline, House Prices Soar!) they may eventually be proved right. I'm always sceptical of these so-called weather experts when they predict what's going to happen in the next few months. Reason being they often get tomorrow's weather wrong.

MillicentBystander

mikemaple wrote: »

Thanks all so far

At least no-one has said - oh my gawd that's a stupid amount you must be heating the whole street

FYI had the thermostat moved to the living room about 4 months ago and all rads have thermostatic value, walls have cavity insulation - but I do need to top up the loft - as it's done to the old levels.

Does cavitity need topping up ?

All good stuff. The recommended loft insulation depth is now 10" so that will probably need doing. Well worth it (approx cost £99 or DIY for much less. One of the DIY stores is selling it at £2/roll, can't remember which one). I'm assuming you are setting the bedroom/rooms only used sparingly temps much less than where you spend the majority of your time? You'll be surprised what a difference it will make to your bills.

Pincher

MillicentBystander wrote: »

Have you been reading the Express as well? They've been predicting -20c for about 2 months now.

Just AutoExpress. They did do a feature on winter tyres last week.

I just had two winters without central heating and no insulation because the house was being renovated, and I had to live on an oil filled Delonghi heater, and kept my builders alive by Calorgas. The house is now all ready for a minor Ice Age.

I want to throughly soak test this house, with its internally drained condensate pipe, which took me a lot of hassle to put in. I don't want a mild winter, give me an arctic blast. I want to see the house wrapped in unmelting snow like an igloo, so I know the insulation is good.

ziggyman99

mikemaple wrote: »

FYI had the thermostat moved to the living room about 4 months ago and all rads have thermostatic valves

Including the living room? If so they will be fighting with the thermostat and you will get undesired flucuations. Take the heads off the TRV's in the lounge.