Third month of heating: reduced gas usage by 5%

Ally_E.

Hi everyone, I'm back with a monthly update of my attempts to reduce gas usage. It's the 3rd month of heating being on and this bitterly cold December I manager to reduce it by 5% compared to last year, even though the average temperature was lower by almost 2 degrees.

Date period: 23 Nov - 22 Dec 2022.
Gas usage: 3,827kW/h in 2022 vs 4,020kW/h in 2021.
Average daily temperature: 4.09C in 2022 vs 6.04C in 2021, located in South London. 10 days of average temps in the minus range, first time average daily temp was recorded in minus range since I started my spreadsheet 3 years ago.

Overall, I'm very happy that I managed to reduce the gas usage even in such an unusually cold weather, albeit it being a small reduction. There were a couple of says with gas usage of 204kW/h a day, which motivated me even more to reduce gas usage and turn the thermostat down a bit. Extra thick cosy socks and second jumper where worn.

Things I've done:
🔹 Reduced thermostat temp from 18.7 to 18.2 
🔹 Reduced hot water temp from 65 to 60 (system boiler)
🔹 Reduced frequency of hot water heating 
🔹 Reduced central heating flow temp to 45 and only put it up on cold days when the system struggles to heat the house
🔹 Bought a chimney sheep for the open fire

If you'd like to read my previous posts, here they are about November and October usage.

macman

Anecdotally, you can save 10% with each 1C drop in set temp. So, if you've saved 5% with a 0.5C reduction, you're spot on.

Ally_E.

It was more than 0.5C reduction in temp this month as the daily kW/h was scaring me. A few days the temp didn't go over 16C in the office and I just worked from the bedroom instead, where it gets a bit warmer if I have both radiators on. 

Cirrus1

I compared my November 21 and 22 bills. I have an 18% reduction in gas usage this Nov and 300% increase in price!
I have not reduced the temperature, but have zoned the house. Last year all the rooms were heated to the same temperature. The bedroom radiators were in cabinets. This summer, the cabinets were ripped out, all the radiators and trvs were changed. I also put in a lot of smart trvs.
The difference is that year the house is heated differently. It gets an equal amount of heat in the morning. The bedroom trvs are then turned down, but leaving the bathrooms on. Doors are closed wherever I can and the open plan area and kitchen gets most of the heating. At bedtime, the upstairs is heated again and downstairs turned down. The smart trvs are brilliant for controlling each radiator easily, no more going to each room to adjust.

Ally_E.

Cirrus1 said:

I compared my November 21 and 22 bills. I have an 18% reduction in gas usage this Nov and 300% increase in price!
I have not reduced the temperature, but have zoned the house. Last year all the rooms were heated to the same temperature. The bedroom radiators were in cabinets. This summer, the cabinets were ripped out, all the radiators and trvs were changed. I also put in a lot of smart trvs.
The difference is that year the house is heated differently. It gets an equal amount of heat in the morning. The bedroom trvs are then turned down, but leaving the bathrooms on. Doors are closed wherever I can and the open plan area and kitchen gets most of the heating. At bedtime, the upstairs is heated again and downstairs turned down. The smart trvs are brilliant for controlling each radiator easily, no more going to each room to adjust.

November was warmer this year compared to last, so savings could have come from that too. My November usage reduced by 44% together with warmer weather and the adjustment to how I heat the house.

It's great to see so many people making an effort to reduce their usage. My projected yearly energy cost went from £3,500 went down to £3,100 and it's only December (I started the projection in September).

Cirrus1

Ally_E said:

🔹 Reduced central heating flow temp to 45 and only put it up on cold days when the system struggles to heat the house
🔹 Bought a chimney sheep for the open fire

Chimney sheep are great, I have one too.

I could never lower my flow temp to 45 degrees and be comfortable. I have too much heat loss going on (glass roof and walls). At ~62 degrees flow temp, the house gets warm easily during ordinary winter temperatures.  During the recent cold spell of -7 degrees, the flow needed to be 70 for the house to stand a chance of heating up in a reasonable timescale. Even then, it took about 5 hrs to go up by 2 degrees. 

The cold spell has been horrifically expensive because of the price increase. If that is not enough, there is the VAT slapped on top of that for the “luxury” of being warm.