What is the cost of running an electric towel radiator ?

[Talay]

I need a large towel radiator and it has to work off the electric. Something around 1.7m x 0.6m seems to be about the right dimensions for the towels I want to hang.

However, some of the wattages on these large radiators frighten the hell out of me !

A 800w element would, were it drawing maximum power 24/7/365 use 0.8*24*365*10p (example unit price) = £700 per year !

But how far can I discount this on the assumption that it will only be drawing power for the time when the temperature falls a couple of degrees below the setting (circa 65c) ?

If I could discount it 50% then it would cost £350 per year and a 75% discount would mean a cost of £175 per year.

A contrast is the dry electric towel radiators available in smaller sizes. Some of these have elements using less than 100w but even 100w on 24/7/365 would only cost £87 by comparison.

Unfortunately I can't get a 1.7m dry unit so would have to use two but that is safer than an unknown cost of running a 800w element one.

Do you have any idea how to calculate the true cost ?

 

[Diyisfun]

They will have a thermostat in the circuit, so it will depend on the heat loss in the room as well as the amount of the rail covered by towels.
I dont think it will be that easy to calcualte.
You could ask the manufacture, they will have figures.

 

[Talay]

They will have a thermostat in the circuit, so it will depend on the heat loss in the room as well as the amount of the rail covered by towels.
I dont think it will be that easy to calcualte.
You could ask the manufacture, they will have figures.

I know that the true calculation is a massive computation of many variables relating to ambient temperature, insulation, etc. even down the the amount of water retained by the towels in question but NASA aren't able to help at the moment

Initial research seems to indicate a circa 65c figure, which triggers power consumption after it drops a couple of degrees. My guess is that this is a fairly heavy on / off situation as the temperature will drop 2c fairly quickly.

You can of course opt for a thermostatic element where you can alter the temperature, though the principle is exactly the same, only at a temperature set by you.

I've spoken to a few sales outlets and they just don't know, nor do they care. Your idea of speaking to the manufacturer is a good one. Thanks.

 

[mikely]

You don’t need to have the heater on 24/7. You can connect it via a time controller such as http://www.tlc-direct.co.uk/Main_Index/Timers_Index/Immersion_Heater_Timers_1/index.html

Using time control and a thermostatically controlled element will greatly reduce the energy use.

 

[Talay]

You don’t need to have the heater on 24/7. You can connect it via a time controller such as http://www.tlc-direct.co.uk/Main_Index/Timers_Index/Immersion_Heater_Timers_1/index.html

Using time control and a thermostatically controlled element will greatly reduce the energy use.

Why would I not want it on 24/7 ? It provides warmth to an otherwise cold room and dries damp towels. With 3 people and at least 6 showers / baths a day between 06:00 and 01:00 there isn't much time to turn it off and still have warm dry towels on demand.

Surely a thermostatically controlled element just allows you to set the temperature you require rather than accept the standard 65c or whatever. I agree that setting it to lower than 65c would reduce the running cost but would it dry the towels ?

However we come back again to figures. One costs more than the other we know but we have no data on whether that extra cost is £5 which is immaterial or £500 which is material. I rather hope I can get some data and cannot believe I am the first person to ask this question or to study the actual costs of their system.

 

[big-all]

if you only want it for drying towels then the middle would be reasonable
if you require it to heat a room thats normally cold then the maximum and even then it wont be enough as the heat loss will be greater

 

[Talay]

if you only want it for drying towels then the middle would be reasonable
if you require it to heat a room thats normally cold then the maximum and even then it wont be enough as the heat loss will be greater

I think I can address the heating issue with a storage heater if the one I have elsewhere is suitable. I think I can locate it sufficiently far away from any water source as to be within regulations but I'll check.

The towel radiator is really for the towels as it would be a terrible design as a pure radiator what with all that surface area exposed to heat loss (even through towels).

I was seriously considering 2 dry ones at around 100w each but am veering towards this model http://buildnet.co.uk/Products/229-wetherby-chrome-electric-towel-rail-600x1700-straight.aspx

Bit of a monster and 800w but well priced and perhaps I upgrade to a thermostatic element to give me the option of reducing the temperature if I want to (still not sure whether this is just pointless though).

 

[mikely]

Why would I not want it on 24/7 ?

To save energy, which seemed to be your primary concern?

I have a 1200 x 500 radiator heated electrically in the summer with a 150W element. It is on for two 5 hour periods a day which works for drying towels.

Surely a thermostatically controlled element just allows you to set the temperature you require rather than accept the standard 65c or whatever. I agree that setting it to lower than 65c would reduce the running cost but would it dry the towels ?

Not sure what you mean by the standard 65C - do you mean the temperature it would reach if on continuously? I would certainly use a thermostatic control for an 800W element; that would get very hot, particularly if covered in towels. I think the thermostat control would make a significant difference to energy consumption.

 

[big-all]

the bigger the element the more economical it is as in getting up to temperature more quickly wasting less energy in heat loss getting there but must be fully heat controlled
but electric will always be around 2 or 3 times the cost off gas for the same amount off heat at the output end

i assume you have no gas ??
is you bathroom well insulated or cold and draughty

 

[Johnmelad]

Towel rads are for warming towels not drying them, and are a waste of energy for warming rooms.

 

[Talay]

the bigger the element the more economical it is as in getting up to temperature more quickly wasting less energy in heat loss getting there but must be fully heat controlled
but electric will always be around 2 or 3 times the cost off gas for the same amount off heat at the output end

i assume you have no gas ??
is you bathroom well insulated or cold and draughty

Slower to heat up with a smaller element is the same cost as quicker with a larger one except that you lose more heat during the slower heating time which makes a smaller element more expensive in a round about way !

No gas so no hot water heating system to tap into I'm afraid.

All elements are thermostatically controlled else they would never stop heating up and the thing would boil dry and then blow up ! The option available would be to control the temperature to either 1 or 2 or 3 or more accurately on some models to say 35c and then in 5c increments up to 70c.

Bathroom is quite poorly insulated (which I can do nothing about) and cold which is why I'm looking at the storage heater option. Looking at this from a towel dryer / warmer perspective rather than a heating one.

 

[Talay]

Just to close this off I thought I'd update.

In the end I bought this one http://www.ebay.co.uk/itm/Thermosta...mm-Straight-Chrome-Plated-RE58-/370579835561? but at £125 delivered not some crazy ass £450 as advertised now !

1600 x 600 is sure is quite large and to be honest, that creates a problem for the fixings, which are really not up to the job. I am looking for some more upmarket fixings / something better designed and manufactured. Yet I paid relative peanuts so I wasn't expecting luxury.

In the end I got a thermostatic model but I'm not sure I would have bothered had the price difference been more than £10 or so as it was.

It is on 24/7 and makes a world of difference to the room compared to the previous 1200 x 500 150w model it replaced. It truly is a radiator and not just a towel warmer and I welcome that in our bathroom.

As to the cost, it has pushed our electricity bill up for sure but it was installed at a time when the temperatures really hit a low patch. I do keep readings every 4 or 5 days and as far as I can estimate, it is costing another £100 or so a year (on a £1500 electric bill - no gas).

Is it worth it ? Yes. It does cost more but the bathroom is now a lovely place to be rather than a freezing cold box.

 

[big-all]

the maximum assuming your units are 12p each is £1.44p a day or a potential £10 a week
lets assume half that on average over the 4 coldest months and off the rest off the time thats £5 a week for 17 weeks= £85 so you assumption off £100 is spot on but off course my assumptions could be well off with the potential to burn £520 worth a year
best way is to turn it down 4 or 5 degrees in 0.5 increments over several days and when it starts to feel cold turn it up 1 degree

any way thanks for the update it makes it all worth it

 

[Talay]

On my electric, with Econ 7 overnight, my costs are 10.1p and 5.1p and thus the maximum potential cost was an horrendous 0.5(17*10.1+7*5.1)/100*365 = £379 !!!

Now the old one was on a theoretical maximum of 0.15(17*10.1+7*5.1)/100*365 = £114 and I guess that was running near full output given the volume of towels and the cold.

I had considered moving a 1kw storage heater into the bathroom to combat the cold at a maximum cost of 1.0(7*5.1)/100*365 = £130.

I hypothesised (from a budgetary perspective) that it might run around 2/3rds capacity with an adjusted thermostat and it won't be a million miles off that. A warmer summer should reduce that somewhat but the cold winter has meant it has probably run longer and harder than expected. I have a spreadsheet which tracks my electric consumption backwards and predicts future consumption, constantly adjusted by taking into account the trends recalculated from the most recent inputs. As I take a reading every week or so, I am fairly well on top of it. You have to be with a £1500 electric bill and the robbing power companies changing tariffs all the time.

As a further comment as to whether it is worth it, for someone considering the options and perhaps being worried, as I was, as to the cost of running a large radiator. If I had sufficient wall space, there are non liquid electric radiators which have metal wire heating elements running through the tubes but they only go out to about 900 x 500 at 100/150w. I would have gone with two of these I think at around £70/80 each.

Consider carefully though where the holes are in the large radiators. We needed 3 holes with large contact areas to dry and heat 3 very large bath sheets. Some radiators have too many holes and the sometimes large gap between means the contact area is not big enough to fully cover a large towel. As they say in carpentry, measure twice, cut once, so do think about it and do measure your wall.