Most efficient electric heaters?

Gerry1

Don't even think of the Magic Dust Non-Storage Heaters...

mark19851234

Aylesbury_Duck said:

mark19851234 said:

Aylesbury_Duck said:

All electric heaters have the same efficiency, because they convert pretty much 100% of the input electricity into heat.  A 1kW radiator costs twice as much to run per hour as a 500W radiator, for example, but the 500W radiator would need to be on for twice as long to heat the same room to the same temperature.  It's more about whether you have access to a cheap night-time tariff, which would make storage heaters a cheaper solution than normal electric radiators, for example.  

Hi. Thanks for this. I do understand that but there are different types of electric heaters such as oil based electric heaters.

Which makes no difference to efficiency.  A 1kW electric heater costs the same to run per hour, whether it's filled with oil, water, custard or whatever you choose to fill it with.

If oil-filled heaters were somehow magically more efficient than other types, the other types would have been discontinued long before now.

Hi. Thanks for the reply. My understanding was that an oil based heater maintained the heat better than my current heater as when u turn it off the heat is completely gone. With an oil heater the heater will still remain warm. This is for a property we rent on AirBNB which has 2 1000W heaters and alone these can sometimes can be costing us £10 a day (£5 each).

mark19851234

We are thinking of replacing them with a 600W radiator. In the description it says this:

The radiator comes complete and pre filled with a formulated glycol fluid which ensures a sound free performance and excellent output of heat, furthermore; the high quality fluid protects the radiator from freezing in temperatures as low as -10C.

Would this not make it more efficient than current heaters?

doodling

Hi,

A heater with significant thermal inertia like an oil filled heater will give more even heat which you might find more comfortable. It won't be cheaper to run however - the heat retained after it is turned off is offset by the heat it wasn't emitting when it was warming up.

I'm surprised that no-one makes a convector heater with proportional control, they would be cheaper (ETA: to buy, not to run) than oil filled radiators but have very similar characteristics in terms of evenness of heat.

Gerry1

mark19851234 said:

We are thinking of replacing them with a 600W radiator. In the description it says this:

The radiator comes complete and pre filled with a formulated glycol fluid which ensures a sound free performance and excellent output of heat, furthermore; the high quality fluid protects the radiator from freezing in temperatures as low as -10C.

Would this not make it more efficient than current heaters?

Unless you use a heat pump, you can't get out more than you put in, no matter what miracle magic goo it has.  And if you let your property go down to -10C you'll have far more to worry about than your magic radiators: burst pipes and flooding come to mind.

If it's impossible to get mains gas (and if oil, LPG and a heat pump aren't realistic) then you need to be thinking of modern storage heaters (genuine ones on E7) as the least worst option.

mysteryUser

As has already been said, all the normal electric heaters use the same amount of energy. It is the case that an oil one will be warmer for some minutes after you turn it off but it'll also be colder for around the same number of minutes when you turn it on. 5 minutes of convector heater will give you the same amount of heat as 5 minutes of an oil filled radiator, of the same wattage. 

To heat more efficiently using electricity, you need to use a heat pump of some sort. 

A possible option is to install inverter based air conditioning, which can do both cooling and heating. 

In my home office I have inverter based air conditioning. It uses around 700watts of electricity and typically gives out 2300watts worth of heat. Costs around 3 times less than a plain old heater. It cost £1128 to buy though. 

Aylesbury_Duck

mark19851234 said:

Aylesbury_Duck said:

mark19851234 said:

Aylesbury_Duck said:

All electric heaters have the same efficiency, because they convert pretty much 100% of the input electricity into heat.  A 1kW radiator costs twice as much to run per hour as a 500W radiator, for example, but the 500W radiator would need to be on for twice as long to heat the same room to the same temperature.  It's more about whether you have access to a cheap night-time tariff, which would make storage heaters a cheaper solution than normal electric radiators, for example.  

Hi. Thanks for this. I do understand that but there are different types of electric heaters such as oil based electric heaters.

Which makes no difference to efficiency.  A 1kW electric heater costs the same to run per hour, whether it's filled with oil, water, custard or whatever you choose to fill it with.

If oil-filled heaters were somehow magically more efficient than other types, the other types would have been discontinued long before now.

Hi. Thanks for the reply. My understanding was that an oil based heater maintained the heat better than my current heater as when u turn it off the heat is completely gone. With an oil heater the heater will still remain warm. This is for a property we rent on AirBNB which has 2 1000W heaters and alone these can sometimes can be costing us £10 a day (£5 each).

That is partly correct, but it's perception and timing of heat delivery rather than using less energy.  An 1kW oil filled radiator will take longer to get the room up to temperature, but as you say, will go on delivering heat after the power is turned off. If you wanted a room warmed to 20C from 10-11am for example, you might need to have the oil rad on from 9.30am to 10.30am, whereas a 1000W fan heater could probably do the job from 9.50am to 10.50am.  I'm afraid you can't cheat the physics, but it's down to how and when you want the heat delivered.

Aylesbury_Duck

mark19851234 said:

We are thinking of replacing them with a 600W radiator. In the description it says this:

The radiator comes complete and pre filled with a formulated glycol fluid which ensures a sound free performance and excellent output of heat, furthermore; the high quality fluid protects the radiator from freezing in temperatures as low as -10C.

Would this not make it more efficient than current heaters?

No. Otherwise we'd all be using them.  What they've typed out is a load of impressive sounding marketing words but which don't find a way around thermodymanic laws.  All electric heaters are effectively 100% efficient, so these can't be 'more efficient' than any others.  All electric heaters do is convert electrical energy into heat energy.  Same as a toaster, same as a kettle.  There might be an LED display or a buzzer or something that draws a miniscule amount of energy, but other than that, they're all the same.

coupleuk

I believe the OP said this was for an AirBnB - though it's not clear if he/she is living in it or renting it out.

Either way, the most important part is to do all you can to insulate the property correctly.

If living in the property........ its usually not much use setting the thermostat to turn the heater off as I've found them to be very hit/miss - much better to set a timer on the heater to switch it off after 1hr - that way you'll probably not notice any drop in temp for an hour after and can decide if you can be bothered to get up and turn it back on lol. You could try the high heat storage heaters but night rates aren't that much cheaper these days and you have to splash out of the cost of buying and fitting them.

If renting out the property.......99% of guests won't understand how HHSR work and will complain, so just don't go there. As much as people will complain on here, I would see if you can fit coin meters just for the heating and let guests decide if they want to leave the heating on when they go out for the day. I've done it in my properties and no complaints as long as you're upfront about it.

Unsure if you have instant water heaters or a water tank - if the latter, check you haven't got it set to be like a kettle 24/7.

Forget Heat Pumps - far too expensive and much more expense in fitting rads etc.

colinsmith

Storage heaters are pretty efficient. Those little 3kw blower heaters cost a bomb to run.