Unusually high gas usage of 43000kwh per year

Qyburn

Are the UFH zones bedrooms? Even if they are it seems pretty costly to heat them to 17 overnight, even more so if they're living areas unoccupied during the night..  

Qyburn

giles007 said:

"For a comparison government guidance for the minimum temperatures for all UK indoor workplaces is 16 degrees (or 13 degrees if doing manual work)."

In addition it used to be illegal to heat above 19 deg, although that was repealed in the late '80s or early '90s when everyone lost interest in energy saving. I think a few decades of cheap energy have got many conditioned to expect high temperatures, compared to earlier generations who wouldn't have dreamed of leaving heating on all day, let alone overnight.

brickwall001

if this helps:

our 6 bed detached usage is 48000 kwh per year. this is with extensive renovations, UFH GF and FF, new boiler. Cavity wall with plasterboard insulation on al external walls. 150mm roof insulation. beam and block GF floor. old gas meter on cubic feet changed to cubic meter, no change in usage. to experiment i tried all settings with temps etc. found the best way was to leave at a constant temp from 4am to 10pm, and a degree or two lower off peak hours. this is for all thermostats, wet UFH and electric UFH. boiler on 60 degree. hot water on from 4am to 7am, then 4pm to 6pm.

to compare neighbours old house is using 56000 kwh. and another new build on my road uses the same as me. same size properties.

your figures seems right.

MultiFuelBurner

giles007 said:

MultiFuelBurner said:

Firstly apologies if this has been answered but I only skim read the whole 9 pages.

Out of interest you mentioned pre under floor heating your gas bill was higher.

What was the difference?

18oC is too cold for us when we sit but that's ok in the Kitchen but not the lounge. 20oC minimum in the lounge for us.

pre UFH, new boiler and new insulation, the usage was 51000kWh annually now it is around 43000kWh

So that was a decent 20% reduction.

So to summise you suspect even the 51000kwh was high and maybe the gas flow being calculated wrongly by your meter but if course less of an issue when gas prices were low.

Now it costs over £4500 a year obviously it is a bigger issue.

Again I haven't read the whole thing fully but sounds like you could ask for it to be tested and that normally means they will replace it with a smart meter and test yours then if found faulty rebilled.

https://www.citizensadvice.org.uk/consumer/energy/energy-supply/your-energy-meter/find-out-if-your-energy-meter-is-faulty/

70sbudgie

Your house seems pretty similar to ours - 5 bedroom, detached, 1980s build, 4 occupants, 2 UFH zones plus radiators. The significant differences being that our children aren't yet teens and we don't have an Aga, but we do have a wood burner in the lounge.

A few years ago our annual gas usage was 24000kWhrs. I've been working hard since then to try to bring it down. I haven't yet done the sums for this year, but 2022 was about 22500kWhrs.

The following are things that I have done that I believe have contributed to this reduction (and hopefully a bit more when Jan - Mar are included in 2023 figures). 

The hot water tank is set to 55°C and only comes on for an hour a day. (I may adjust this as I'm not sure that it is quite enough. I think 1.5hrs would be better)

The boiler flow temp is set to about 57°C.

Each of the 3 heating zones are set to different times, depending on which room they are. The kitchen is a large concrete slab with UFH that takes a long time to warm up and cool down. It is set to 17°C from about 5am to 9pm (I just checked, I thought it was on for less time than this) and 14°C otherwise. The reason I thought it was on for less time is because the room keeps warming up even though the UFH stops calling for heat. Now, the stat is saying the room is at 19°C. 

The other UFH zone is in the bedroom and that varies between 17.5°C for a couple hours morning and evening and 15.5°C the rest of the time. 

The rest of the house is set to 18°C morning and evening, 17.5°C during the day and 15°C at night. 

I have turned off the radiators in the lounge as they are huge, were heating the room too much and using all the hot water so other radiators weren't warming up. That said, one appears to have a broken TRV as it doesn't turn off. We light the wood burner if we are going to be in the lounge for a few hours. 

I also have a couple small, FIR panel heaters that I use for localised heating - one in our home office and one in the lounge, if we don't plan to be there long enough to light the fire.

One of the things I realised last summer, was that having the stat for the main house on a constant 18°C, meant that the boiler would fire in the early mornings - even in July when the house would later get too warm for comfort. As soon as I noticed this, I turned the heating off completely and that made a big difference to gas consumption. When I turned the heating back on in September (I couldn't stick it out till October), I tried tweaked the day temp down to 17.5°C. I wasn't sure if that would be comfortable enough, but it was easier coming from no heating. (As suggested above by someone).

There has been a lot of discussion about what is the right temperature, but only you can know that and it will be where you are willing to compromise between comfort and cost. I would suggest turning the temperatures down either a half or one degree every couple of weeks. When you feel uncomfortable, tweak it back up by one increment. 

I would also suggest lengthening the night time temperatures. The day time temp probably only needs to kick in about half to an hour before you start using that room (wake up for bedrooms), and can switch back to night temps half to an hour before you vacate that room. For us that means the bedroom UFH comes on earlier than the kitchen, but also the main house turns switches to night not long after the children go to bed. 

My last point is that the only reason I have been able to fine tune my gas use like this is because I have the data from a smart meter. You can get similar amounts of data if you are prepared to put in the work of taking frequent and regular meter readings. 

Don't get a smart meter confused with a modern digital meter. The smart bit is the communication module. It is also possible to set smart meter reading collection to once a month, so minimising any EMF. 

giles007

Qyburn said:

Are the UFH zones bedrooms? Even if they are it seems pretty costly to heat them to 17 overnight, even more so if they're living areas unoccupied during the night..  

No UFH is downstairs

The 17 degrees schedule is to keep it at 17 IF it drops below, it rarely if ever does overnight, so effectively the UFH is off during these times

70sbudgie

I think you would be surprised how often the boiler fires at this temperature - I know I was when I saw the data for mine. 

If you are so confident that the boiler doesn't need to fire, it shouldn't make any difference if you drop the overnight temp by a degree or two. If it was firing to keep the temperature at 17°C overnight, you will make some savings.

kazwookie

giles007 said:

No UFH is downstairs

The 17 degrees schedule is to keep it at 17 IF it drops below, it rarely if ever does overnight, so effectively the UFH is off during these times

Have you got up at say 3am and had a wander over the UFH down stairs in bare feet to check it is NOT working??  if not I would suggest you do.

MarzipanCrumble

Don't get a smart meter confused with a modern digital meter. The smart bit is the communication module. It is also possible to set smart meter reading collection to once a month, so minimising any EMF. 

Sorry to be ignorant but what does this mean?

chris_n

May have missed it but is the ufh in a concrete slab or on a suspended floor, either way how much insulation is below it and is there perimeter insulation between the heated floor and the outside walls?