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The number of methods to provide heating to your accommodations is enormous.  Here we compare the potential running costs of various methods of heating.

cost of running heatersWe exclude larger heating systems here, like central heating, groundsource heating or airsource heating as these are very different and require large capital expenditure to install. These are considered in a separate article.

To get a meaningful comparison, the same power output and hence the same energy use is used in each case. The calculations are based on each heater having a power output of 3kW, and operating for 5 hours a day for about one third of a year. 3kW was chosen since this is the maximum power output of an electrical heater on a single ring main plug socket and since all the other appliances can out put the same heat power. All appliances are also assumed to be non thermostatically controlled, i.e no maximum room temperature has been set. The rate of heat loss from a room is also not considered here.

Heater (All 3kW) Efficiency Estimated Running cost per hour Running cost per 5 hour period (no thermostat) Running cost per year 5 hours a day for one third of the year Indicitive Purchase Price Indicitive installation Price
Electric Bar Heater 100 % £0.561
(1.1kg)
£2.805
(5.5kg)
£342.21
(671.6kg)
£ 40 £ 0
Electric heaters are usually 1,2 and 3kW, 3kW is the maximum you can have on a UK ring main. The 5 hour costs assume that the heater does not have a thermostat on it. Having a thermostart will almost certainly reduce the operational costs of the heater also the 1 kW setting will be three times cheaper than the 3kW setting.
Electric Fan Heater 100 % £0.561
(1.1kg)
£2.805
(5.5kg)
£342.21
(671.6kg)
£ 20 £ 0
Electric heaters are usually 1,2 and 3kW, 3kW is the maximum you can have on a UK ring main. The 5 hour costs assume that the heater does not have a thermostat on it. Having a thermostart will almost certainly reduce the operational costs of the heater also the 1 kW setting will be three times cheaper than the 3kW setting.
Electric Oil Filled Radiator 100 % £0.561
(1.1kg)
£2.805
(5.5kg)
£342.21
(671.6kg)
£ 80 £ 0
Electric heaters are usually 1,2 and 3kW, 3kW is the maximum you can have on a UK ring main. The 5 hour costs assume that the heater does not have a thermostat on it. Having a thermostart will almost certainly reduce the operational costs of the heater also the 1 kW setting will be three times cheaper than the 3kW setting.
Electric Convection Heater 100 % £0.561
(1.1kg)
£2.805
(5.5kg)
£342.21
(671.6kg)
£ 40 £ 0
Electric heaters are usually 1,2 and 3kW, 3kW is the maximum you can have on a UK ring main. The 5 hour costs assume that the heater does not have a thermostat on it. Having a thermostart will almost certainly reduce the operational costs of the heater also the 1 kW setting will be three times cheaper than the 3kW setting.
Single Electric Storage Heater 80 % £0.353
(1.1kg)
£1.763
(5.5kg)
£215.025
(671.6kg)
£ 350 £ 250
There are efficiency issues with storage heaters, they heat at night and output in the day and you may not want the heat, so you may waste it.
Gas Fire Flued 50 % £0.234
(0.6kg)
£1.17
(3.2kg)
£142.74
(384.3kg)
£ 500 £ 300
Much of the heat from flued gas fires goes up the chimmey and their efficiency is therefore poor about 50%, and some suggest efficiency is even lower.
Gas Fire Flueless 95 % £0.123
(0.6kg)
£0.616
(3.2kg)
£75.126
(384.3kg)
£ 500 £ 500
Flueless fires use cataltic converters and do not rely on a chimney to vent nasty gases, they are therefore much less wastefull.
Gas Wall Heater 90 % £0.13
(0.6kg)
£0.65
(3.2kg)
£79.3
(384.3kg)
£ gaswallheate £ 300
Bottled Gas Fire 75 % 78 pence £ 3.9 £ 475.8 £ 80 £ 0
A 15kg Bottle of butane is assumed for this calculation.
Wood Burning Open Fire 30 % 83 pence £ 4.15 £ 506.3 £ 600 £ 600
Only wood log costs are used to calculate prices here.
Coal Burning Open Fire 30 % 26 pence £ 1.3 £ 158.6 £ 600 £ 600
Smokeless Coal Open Fire 30 % 63 pence £ 3.15 £ 384.3 £ 600 £ 600
Wood Burning Closed Fire 70 % 36 pence £ 1.78 £ 216.986 £ 800 £ 1000
If you are burning your scrap wood the costs are zero!
Coal Burning Closed Fire 70 % 11 pence £ 0.56 £ 67.971 £ 800 £ 1000
Smokeless Coal Closed Fire 70 % 27 pence £ 1.35 £ 164.7 £ 800 £ 1000

The second table combines the fuel costs over an extended period of time with installation and purchase price of the unit you buy, to help with long term decisions, the numbers are based again on each heater having a power output of 3kW, and operating for 5 hours a day for about one third of a year.

Heater (All 3kW) Running, Purchase and Installation Costs, 1 Year Running, Purchase and Installation Costs, 5 Years Running, Purchase and Installation Costs, 10 Years Running, Purchase and Installation Costs, 15 years
Electric Bar Heater £ 382 £ 1751 £ 3462 £ 5173
Electric Fan Heater £ 362 £ 1731 £ 3442 £ 5153
Electric Oil filled Radiator £ 422 £ 1791 £ 3502 £ 5213
Electric Convection Heater £ 382 £ 1751 £ 3462 £ 5173
Single Electric Storage Heater £ 815 £ 1675 £ 2750 £ 3825
Gas Fire Flued £ 943 £ 1514 £ 2227 £ 2941
Gas Fire Flueless £ 875 £ 1176 £ 1551 £ 1927
Gas Wall Heater £ 729 £ 1047 £ 1443 £ 1840
Bottled Gas Fire £ 556 £ 2459 £ 4838 £ 7217
Wood Burning Open Fire £ 1706 £ 3732 £ 6263 £ 8795
Coal Burning Open Fire £ 1359 £ 1993 £ 2786 £ 3579
Smokeless Coal Open Fire £ 1584 £ 3122 £ 5043 £ 6965
Wood Burning Closed Fire £ 2017 £ 2885 £ 3970 £ 5055
Coal Burning Closed Fire £ 1868 £ 2140 £ 2480 £ 2820
Smokeless Coal Closed Fire £ 1965 £ 2624 £ 3447 £ 4271

Heating rooms electrically at the standard rate is as expensive as you would expect, what is perhaps surprising is the cost of open fires.  These are very inefficient because so much of the heat energy from the fuel you burn ends up going straight up the chimney or into the wall.  The most economic bottle gas fire option cost quite a lot more than an electric bar heater, but they are very cheap to buy.   On pure cost grounds the most economic running cost are with a

  • Storage heater
  • Flueless gas fire
  • Gas wall heater
  • Coal burning closed fire or stove

However with all of these option unless you already have them installed there is a relatively high installation cost, however long term they pay back this cost.

Wood is horribly expensive to burn as is smokeless coal particularly in open fires if you are going to burn fuels like this it is far more cost effective to use a closed system like a small stove.

Long term flueless fires and gas wall heaters seem like a good cost effective way to heat your home.

Comments and Questions

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Mr - ck  2015-01-19 09:25:40
Your table shows one storage heater, with the implication that they are all the same. This is not the case. There are four different types. You also say that storage heaters are less efficient. This terminology is misleading, because ALL electric heaters are 100% efficient in converting electricity to heat.
What is true is that, depending on the type or heater, some of it is output to the room to some degree at times when you may not want heat.
BUT:
1. Your comparison is therefore misleading and incorrect in various ways, as you say it is based on heaters operating for five hours a day, whereas basic storage heaters provide heat all through the day, and a 3kw storage heater outputs on average 1.5kw for 17 hours. (Note that 3Kw is the rate at which is charges for 7 hours, on max setting, NOT its output). Also, storage heaters tend to be 3.4 kw, not 3kw. So, to get 3kw of heat for your comparison, you would need two 3.4 kw heaters in your room, which at the time of writing would cost about £1.33 for a full charge, giving a cost per hour of about 16p NOT 29p. Of course, it depends whether you need and want this heat all through the day, but you must acknowledge that you are not comparing like with like in terms of the time the heat is available. But, also, this is where the different storage heater types become relevant.
2. However, the other factor is the type of heater. The four types are:
a. Manual charge control.
b. Auto charge control.
c. Auto charge control fanned, with thermostatic heat output control.
d. High heat retention, with computerised intelligent charge control, and timed thermostatic heat output control.
This is in order of controllability and cost-effectiveness. Type "d" are very new and far more cost effective than earlier types, and here's the big thing, they output far less heat when you don't want it. So you can have your five hours a day of heat with these, and the heat you don't use or need will be stored for the next day. These new types are specifically recognised in the SAP ratings, which has a category of "High Heat Retention Storage Heater". At present only one manufacturer produces them.
There is a LOT of misleading info out there about electric heating, and so many manufacturers whose adverts on my view deliberately mislead. In fact, one manufacturer at east has had a judgement against them for misleading advertising.
So, please, correct your site with regard to Storage Heaters to prove more accurate and meaningful figures and comparisons.
(One final note, I am not sure that 3kw is a good benchmark, as depending on levels of insulation etc, many rooms will have a heat loss of only 1, 1.5 or 2kw).
reply - rdh  2015-01-19 16:21:22
Hi

This is a simple comparison table, it is not exhaustive and to do a comparison, one needs to use the same parameters. The info you provide is however great, Our thanks.

In the table think of it this way, if one has a 3kW demand storage heater and you switch it on at night for five hours only, this will cost what it says in the table (when you include a useless heat loss factor, shall we call it efficiency for simplicity).

Yes it is 100% efficient at converting electricity to heat but this is not useful heat, this is stated in the column to the right of the table.

We will not be changing the table it is fine for the context it was intended and that is broad paintbrush comparison with other fuels and their combustion efficiencies. A separate article all on storage heaters would seem a better approach.

We have also seen incredible claims for electric heaters, claiming greater efficiency. Basically all electric heats convert 100% electricity to heat, but some place the heat better i.e where it is wanted and time it output more intelligently.
Nr - Rashid  2014-11-11 22:37:40
Very cleverly displayed

how did you calculate how much it will cost for a bottled gas per kwh?
reply - rdh  2014-11-13 21:33:32
Hi Rashid

It is approximately £35 for 15kg of butane.
13.7 kWh of combustion energy is in 1kg of Butane, this is standard data from the textbooks.

15kg * 13.7kWh = 205.5 kWh per 15kg cylinder (costing £35)
3500 pence / 205.5 kWh = 17 pence/kWh

but not all of that energy will be realised as heat. If the heater is for example 75% efficient i.e. Not all the butane is burned.

so to actually output 1kWh as heat you need more butane, which costs more.

so taking this into account 17 / (75/100) = 22.7 pence/kWh of actual heat.

does that answer the question?

cheers

Richard
Flueless gas fires - Steve  2014-03-24 16:36:31
You have forgotten to notice that Flueless gas fires need a secondary form of heat, in order to let the catalytic convertor to work correctly. The air being fed into the fire needs to be warm, otherwise there is a greater risk of condensation and damage. All of the manufacturers instructions, quote that it is to be used in conjunction with central heating, not as a stand alone product.The running costs of the central heating, should then be added into the calculation, so making them very inefficient, maybe 30%
reply - rdh  2014-04-10 09:05:39
We have tried to contact suppliers of these to get more data on these, but to no avail. we will post when we get more data.
convector heator - Richard  2011-08-07 16:45:45
the 3kw relates to electrical power consumption. is your Bionare rated at 3kw it should say on it somewhere? Any electrical device with a power consumption of 3kW will cost about 40 pence per hour to run full blast. It probably has a thermostat in it so if this is set at a reasonable temperature then the power consumption is likely to be less, because the heater will switch off at a preset temperature.
3kw convector heater bionaire - brenda hughes  2011-08-07 10:04:22
can i take it that the tables above for a 3kw convector are what my bionaire would use. we have bought it for the conservatory to heat for a few hours a day as it has no radiator. is there something more economical or is this the cheapest way. thanks.