gas fire, how much gas?

qwertyjjj

HappyMJ wrote: »

The 15kw or even the maximum setting of 30kw is only consumed whilst the boiler is running. If you listen to the boiler it shuts off till the water cycling around the system cools down enough then it starts up again. I'd say the 30kw is only used for about 30 minutes whilst the house comes up to temperature from cold then it regulates itself down to a fair and reasonable usage till you turn it off.

npower gas seems more like 7-8p per kWh on checking.

Gas fire 3kw of heat output for 24p. (6kw*4p)....The gas boiler 8kw of heat output on minimum setting for 36p (9kw*4p). You could if you turned radiators down in unused rooms only require the gas boiler to be on half the time instead of all the time costing you only 18p per hour.

Gas fire: 6kw*7p = 42ppkWh with 3kW output.
Boiler with only downstairs radiators on during day: 15Kw*7p * -15% efficiency reduction for turning off upstairs = 89ppkWh

No idea, what the power output of a radiator is compared to the boiler's 15kW input. So, it's really a question of does the gas fire do the job enough or not?

HappyMJ

Yes I'm with Npower as well 7.173p + tax for the primary units of gas per kWh. Quite expensive. It's cheaper for me to use E7 electricity to heat with. Although what you really should do is take the annual usage let's say 16,500kWh which would cost £660 per year to figure out your gas rate i.e that would be 4p per kWh. I use less than 4,572kWh per year so my gas unit charge is 7.5p but most people easily use more than that.

gatita

quertyjjj, Thanks for posting your query, I have often wondered the same. I have to say I am not all that much clearer after reading all the answers you got! It seems to me so very complicated to work out.
I have to say I am really worried about the gas bills this coming winter, it was hard enough last year so heavens know how I shall cope this year.

HappyMJ

gatita wrote: »

quertyjjj, Thanks for posting your query, I have often wondered the same. I have to say I am not all that much clearer after reading all the answers you got! It seems to me so very complicated to work out.
I have to say I am really worried about the gas bills this coming winter, it was hard enough last year so heavens know how I shall cope this year.

It's not too complicated. Well maybe it is... It's always cheaper to use the gas boiler but the maths involved makes it look like it's more expensive. Only use the gas fire on a cold summers night for less than an hour or if you need extra heat in the winter with the gas boiler running maybe only required if it's -20C outside and people are in and out the front door. If you only use the gas fire in the winter every other part of the house will be freezing cold. So when you go to bed the bedroom will be freezing so what would you do? Put an electric heater on? You will get more heat for the same money by using the 90% efficient gas boiler over a 50% efficient gas fire.

gatita

Happy MJ Thank you so much for your response, what you say is SOOOOOOOOOO true regarding just having the gas fire on in the lounge and the rest of the house is freezing!!
and as for getting undressed in the bathroom and waiting for the hot water to come on brrrrrrrrrrrh ....then BLISS lol lol only thing is I never want to come out lol.
I find it incredible that now to be warm all day it has become somewhat of a luxury. I have worked all my life, never had benefits, and here I am talking about trying to keep warm! Something wrong somewhere me thinks.

qwertyjjj

HappyMJ wrote: »

It's not too complicated. Well maybe it is... It's always cheaper to use the gas boiler but the maths involved makes it look like it's more expensive. Only use the gas fire on a cold summers night for less than an hour or if you need extra heat in the winter with the gas boiler running maybe only required if it's -20C outside and people are in and out the front door. If you only use the gas fire in the winter every other part of the house will be freezing cold. So when you go to bed the bedroom will be freezing so what would you do? Put an electric heater on? You will get more heat for the same money by using the 90% efficient gas boiler over a 50% efficient gas fire.

I was only talking about using the gas heater during the day though. The boiler would come on at night time to heat the upstairs of the house.

HappyMJ

qwertyjjj wrote: »

I was only talking about using the gas heater during the day though. The boiler would come on at night time to heat the upstairs of the house.

I thought you were turning the bedroom radiators down when you left in the morning then turned them back up when you came to bed.

And lastly ( ), if you turn off say 5 radiators in the house during the day, but leave 5 on, does that reduce the gas consumption from the boiler by 50% or does the boiler use the same amount of gas regardless as it's just heating water in the pipes (no thermostat)

If you actually did that it will save you money. There is a TRV that will do that automatically for you. Look at this http://www.etrv.co.uk/ . The eTRV will save you up to 20% of your heating bills as you are not unnecessarily heating the bedrooms when you are not using them. You can program them to have the bedroom temperature for instance - 19 in the evening, 10 overnight, 19 during the morning and back to 10 during the day. You would have to figure out what your annual heating spend is to see if getting them is worth it. They are £50 each so for a house with 10 radiators it would cost £500 in total. I'm sure there are cheaper alternatives.