Heating on all night and Degree Days

nxdmsandkaskdjaqd

I have not seen this website mentioned before here.  I have been using the site for several years to measure my weekly gas usage verses the outside temperature.  You will need to go to the website to understand more about the methodology.  https://www.degreedays.net/

 In summary, my typical gas usage over the coldest months is 11 KW DD (Degree Days).   So for every degree day below a certain baseline temperature I use 11 KW.

 Under normal winter conditions the heating is typically set to come on at 7am and go off at 11pm (home all day).  Set temperature during the day is 19.5 rising to 21 during the evening.

 For the last week we have had 5 cold nights of -7 and -8 centigrade.  When we hit temperatures of -5C I leave the heating on all night with a set temperature of 19C.

 So for the last 7 days my usage was 10.4 KW per DD, verses my typical DD of 11KW.

 In summary, it didn’t cost me anymore than my typical usage to leave my heating on all night.   My assessment is that the cost of heating the house in the morning is the same as leaving the heating on all night.

 My usage of gas for the week was 1052 KW, so a cost of £100 based on 10pence per unit (fairly large house with 5 beds, built around 1995, radiator central heating, modern condensing boiler about 7 years old).

 Just my experience.

 MORE INFO: So what are degree days?

Degree days are essentially a simplified representation of outside-air-temperature data. They are widely used for calculations relating to the effect of outside air temperature on building energy consumption.

 "Heating degree days", or "HDD", are a measure of how much (in degrees), and for how long (in days), outside air temperature was lower than a specific "base temperature" (or "balance point"). They are used for calculations relating to the energy consumption required to heat buildings.

nxdmsandkaskdjaqd

Deleted_User said:

Awesome! Just what I'm looking for. Cheers!

We discovered in the past few days that if we leave the CH on 24/7 set to 12 degrees it won't come on EVER provided we light the logburner each day and night time temps don't drop to silly levels AND day time temps don't go above zero.

Just to add.  Under -7 conditions outside the house temperature overnight (with no heating) only drops to about 16/17C. It seems to retain its heat in comparison to other peoples comments on here.

Alnat1

nxdmsandkaskdjaqd said:

Just to add.  Under -7 conditions outside the house temperature overnight (with no heating) only drops to about 16/17C. It seems to retain its heat in comparison to other peoples comments on here.

Compared to others on here you have your heating temperature set much higher for a much longer time and use much more gas!

Reed_Richards

nxdmsandkaskdjaqd said:

 Under normal winter conditions the heating is typically set to come on at 7am and go off at 11pm (home all day).  Set temperature during the day is 19.5 rising to 21 during the evening.

 For the last week we have had 5 cold nights of -7 and -8 centigrade.  When we hit temperatures of -5C I leave the heating on all night with a set temperature of 19C.

 So for the last 7 days my usage was 10.4 KW per DD, verses my typical DD of 11KW.

 In summary, it didn’t cost me anymore than my typical usage to leave my heating on all night.   My assessment is that the cost of heating the house in the morning is the same as leaving the heating on all night.

It should cost you less to leave the heating off overnight.  But it's possible that if you do that, when the heating comes on in the morning the boiler works so hard bringing the house up to temperature that it performs less efficiently.  So 24 hours of gentle and efficient boiler operation cost you less than 16 hours of operation with the initial part being the boiler running hard.

Alnat1 said:
Compared to others on here you have your heating temperature set much higher for a much longer time and use much more gas!

The temperatures and times are very close to the ones I use, but I am in the fortunate position of still being able to afford to heat my house as I always used to.  Others on here aren't so fortunate.
      

nxdmsandkaskdjaqd

Alnat1 said:

nxdmsandkaskdjaqd said:

Just to add.  Under -7 conditions outside the house temperature overnight (with no heating) only drops to about 16/17C. It seems to retain its heat in comparison to other peoples comments on here.

Compared to others on here you have your heating temperature set much higher for a much longer time and use much more gas!

We have lived in the house for some 25 years.  In the early days our annual cost of heating was 25000kw pa.  We have changed the boiler and added more insulation to the loft and now our annual usage is 20000KW pa.  Yes we do use a lot of energy, it's a fairly large house and we are here all day.