I have a quick look through my octopus online December fuel bills, in the very cold months like December/January I have recorded high 1500 kWh monthly gas readings, when it was 3.5p a kWh it was not to bad around £52, I am on a flexible gas tariff currently around 7.5p, however this due to double in October so I and probably looking around £225 a month, in January I believe it will jump to around 20p kWh I will probably looking around £300 for the month ? My combi boiler has always been set at Eco, however, I have now found that setting is 75 degrees C, I altered the setting to 40 degree C for water and 55 degrees for the heating. I used to set my thermostats to 22 degrees C, I intend to set the room to 20 degrees C and bedrooms to 18 degrees C. Hopefully I can reduce my winter consumption by 20/30%
Apparently, these boilers rarely run at full power, around 50%. On that basis, we will probably have the boiler running for an hour in the morning, and a couple of hours in the afternoon/evening, switching to electric at 9.30pm. GAs consumption around £5-6 a day, which I can live with!