Most energy efficient electric heating?

siulas

Hello,

I've read about Infrared, underfloor, lucht and few other electric heaters.
Would anyone have experience on which one of those is most efficient?
is there a place on the web with all of them compared?

Thanks
siulas

2011

% efficiency = (energy output / energy input) x 100

A 3kW electric heater that consumes 3kW of electricity will provide 3kW of heat. Using the above formula we can conclude that this electric heater (like alll electric heaters) is 100% efficient. This sounds wonderful, but it's not because electricity is expensive. This is why it is generally cheaper to heat a home using a gas boiler even if the boiler is only 80% efficient.
Hopefully this makes sense

siulas

2011 wrote: »

% efficiency = (energy output / energy input) x 100

A 3kW electric heater that consumes 3kW of electricity will provide 3kW of heat. Using the above formula we can conclude that this electric heater (like alll electric heaters) is 100% efficient. This sounds wonderful, but it's not because electricity is expensive. This is why it is generally cheaper to heat a home using a gas boiler even if the boiler is only 80% efficient.
Hopefully this makes sense

And how about lucht radiators that heat up oil inside them for 20 minutes and then keeps emiting heat from it? Is that just bs?

Sleeper12

siulas wrote:

And how about lucht radiators that heat up oil inside them for 20 minutes and then keeps emiting heat from it? Is that just bs?

Same formula as above. If you check up the price per kw of gas and electricity you'll see that all electric heating is more expensive to heat a room than gas or oil.

2011

Sleeper12 wrote: »

Same formula as above.

Exactly.
The oil in the heaters is not there to improve on 100% efficiency.

If electrical heaters were more than 100% efficient they would be defying the law of conservation of energy. This states that energy can neither be created nor destroyed.

siulas

In nutshell then it doesn't really matter which electric heater I put at home, they all are very similar in efficiency?
What would be the best way to reduce my bill then? Put insulation?

Sleeper12

siulas wrote:

In nutshell then it doesn't really matter which electric heater I put at home, they all are very similar in efficiency? What would be the best way to reduce my bill then? Put insulation?

Insulation is great for all types of heating. Electricity, gas and oil. So the rooms will heat quicker and hold the heat longer. I have gas heating and insulated the house about 9 years ago. Can't say I noticed a difference in the bills as they seem to go up each year anyway. It's the comfort level that you'll notice most of all.
You are hung up on electricity so I'm guessing that you are in an apartment or somewhere that you can't get gas or oil?

siulas

Sleeper12 wrote: »

Insulation is great for all types of heating. Electricity, gas and oil. So the rooms will heat quicker and hold the heat longer. I have gas heating and insulated the house about 9 years ago. Can't say I noticed a difference in the bills as they seem to go up each year anyway. It's the comfort level that you'll notice most of all.
You are hung up on electricity so I'm guessing that you are in an apartment or somewhere that you can't get gas or oil?

Yes, Unfortunately I'm in apartment and my only option is electric heating. I have Dimplex storage heaters at the moment and was trying to figure out if there is point to change them to something better, more efficient, but it's very hard to find direct comparison between all options. I've seen a lot of people rooting for underfloor heating as well, I'm just not sure if it's worth upgrading to anything at this stage.

ED E

siulas wrote: »

Yes, Unfortunately I'm in apartment and my only option is electric heating. I have Dimplex storage heaters at the moment and was trying to figure out if there is point to change them to something better, more efficient, but it's very hard to find direct comparison between all options. I've seen a lot of people rooting for underfloor heating as well, I'm just not sure if it's worth upgrading to anything at this stage.

If you've storage heaters using night rate electricity (a night rate meter) then thats the best possible case for electric heating.

2011

siulas wrote: »

Yes, Unfortunately I'm in apartment and my only option is electric heating.

Understood.

I have Dimplex storage heaters at the moment and was trying to figure out if there is point to change them to something better, more efficient, but it's very hard to find direct comparison between all options.

The advantage of storage heaters is that they use cheaper (night rate) electricity to heat up. Theoretically they will release much of this heat during the day. In reality they take longer to heat up and the heat is released in an poorly controlled way during the day. They should result in cheaper heating but most people are not happy with the result.

I've seen a lot of people rooting for underfloor heating as well, I'm just not sure if it's worth upgrading to anything at this stage.

This works best under tiles are they conduct the heat well. However it takes quite a while for them to heat up. Installing carpet or wooden flooring over underfloor heating does not work well as these materials are good insulators making it harder for the heat to be released where you want it (in the room).

Also replacing underfloor heating can be very expensive when the elements fail (they all fail at some point).

Oil filled electric heaters heat much quicker and give a "nicer" (less dry, similar to conventional radiators) more controlled heat.
If any electric heaters are used during the day the electricity consumed will be charged at peak (day) rate.

siulas

2011 wrote: »

Understood.



The advantage of storage heaters is that they use cheaper (night rate) electricity to heat up. Theoretically they will release much of this heat during the day. In reality they take longer to heat up and the heat i realised in an poorly controlled way during the day. They should result in cheaper heating but most people are not happy with the result.



This works best under tiles are they conduct the heat well. However it takes quite a while for them to heat up. Installing carpet or wooden flooring over underfloor heating does not work well as these materials are good insulators making it harder for the heat to be released where you want it (in the room).

Also replacing underfloor heating can be very expensive when the elements fail (they all fail at some point).

Oil filled electric heaters heat much quicker and give a "nicer" more controlled heat.

Thanks for your opinion, from reading online I'm keen to try oil filled heaters as they look nice, plus in theory I should use less electricity as I would turn them on only when I need them, not use them at night. But then as well it probably would take longer to heat up the room...
jesus, there are so many things to consider.. and so many options. I'm thinking maybe try calling few electricians and ask their opinion on electric heating options..

brightspark

While all forms of electric heating are practically 100% efficient, your usage of that heat may not be.

Storage heaters heat over night using cheaper electricity than a heater powered during the day, however if you are out all day most of that energy is wasted keeping an empty apartment warm.

The radiant heaters (halogens and infra red) will provide immediate direct heat to someone within a few feet of the heater, but I wouldn't like to leave one unattended and once you turn it off it will almost immediately become cold.
The infra red ones will also tend to heat objects such as people more than the air.

An oil filled radiator will heat up slower and release the heat over a slightly longer period of time, and will remain warm for a period after you switch it off. I'd consider them a lot safer than the radiant heaters especially where children or elderly people are involved.

So called smart heaters may save you money by more accurate temperature regulation meaning you don't over heat a room, but the cost of that smart control may take some time to recover!

I've no experience of underfloor heating, but I'm guessing it's expensive to install (especially in an existing property) and difficult to repair when it fails.

siulas

brightspark wrote: »

While all forms of electric heating are practically 100% efficient, your usage of that heat may not be.

Storage heaters heat over night using cheaper electricity than a heater powered during the day, however if you are out all day most of that energy is wasted keeping an empty apartment warm.

The radiant heaters (halogens and infra red) will provide immediate direct heat to someone within a few feet of the heater, but I wouldn't like to leave one unattended and once you turn it off it will almost immediately become cold.
The infra red ones will also tend to heat objects such as people more than the air.

An oil filled radiator will heat up slower and release the heat over a slightly longer period of time, and will remain warm for a period after you switch it off. I'd consider them a lot safer than the radiant heaters especially where children or elderly people are involved.

So called smart heaters may save you money by more accurate temperature regulation meaning you don't over heat a room, but the cost of that smart control may take some time to recover!

I've no experience of underfloor heating, but I'm guessing it's expensive to install (especially in an existing property) and difficult to repair when it fails.

When I was looking at underfloor heating i didn't of practicality, but you and @2011 have a good point there and it's probably not the best option.

I will try to speak to few electricians about oil based heaters and see what they say.

Thanks for your help

bootser

Have u had a look at inverter heaters? I bought one a couple of years ago and find it very good for heating my large kitchen/dining/living room area very quickly in the mornings. They burn very low odour kero but are plugged in for fan and timer.

brightspark

bootser wrote: »

Have u had a look at inverter heaters? I bought one a couple of years ago and find it very good for heating my large kitchen/dining/living room area very quickly in the mornings. They burn very low odour kero but are plugged in for fan and timer.

I hope you have lots of ventilation, not something I'd risk using but I'm a little paranoid about CO poisoning etc.

bootser

brightspark wrote:

I hope you have lots of ventilation, not something I'd risk using but I'm a little paranoid about CO poisoning etc.

I've been using it for a couple of years, also have a solid fuel stove and ofch indoor burner, have always had a CO alarm and regular servicing. The inverter is great to heat the downstairs in the mornings, I would think it would be great in an apartment?

siulas

bootser wrote: »

I've been using it for a couple of years, also have a solid fuel stove and ofch indoor burner, have always had a CO alarm and regular servicing. The inverter is great to heat the downstairs in the mornings, I would think it would be great in an apartment?

Yes, inverted heater seems like a bit of a hassle, there is no way to set it up as radiator on the wall

I have been just reading up a little bit online about lucht heaters, somehow I thought they are oil based, but it seems like not. Any suggestions on oil based electric radiators? How about farho heaters?

Joe1919

siulas wrote: »

In nutshell then it doesn't really matter which electric heater I put at home, they all are very similar in efficiency?

I would dispute the above, if you consider that the purpose of the heater is not to heat the room as such, but to make the people in the room feel more comfortable.
A radiant heater, for example, can make a person more comfortable at a lower room temperature (heat losses are less) and hence may be more efficient. They will even work outside in a patio.
Some radiant heaters are great if you want quick heat, say in the morning for breakfast before you go out. I will include the gas supser here (4.5 kw of instant radiant heat).
There are other differences e.g The electric oil filled radiators are very slow to warm up compared to fan heaters etc.
I personally hate the noise of fan heaters and cant stand the glare of halogen heaters.

Bruthal

2011 wrote: »

% efficiency = (energy output / energy input) x 100

A 3kW electric heater that consumes 3kW of electricity will provide 3kW of heat. Using the above formula we can conclude that this electric heater (like alll electric heaters) is 100% efficient. This sounds wonderful, but it's not because electricity is expensive.

That's because the efficiency is only being measured at the final point. But payment for electricity includes the inefficiencies which are all before the heater element.

Bigus

Google heat loss formula.

I.e. Heat loss is directly proportional to temperature difference .

As regards electric heater efficiency, under floor heating will be more efficient as it heats a much larger area up to a much lower temperature, i.e. Heat loss is dependent on temperature difference so a huge floor heated to 20 degrees C might have the same amount of energy contained heat as a radiator at 65 degrees C , but we both know which will lose the heat more slowly.

Also underfloor heating will result in less room temperature fluctuation, so can be run at a lower room temperature setting , yet feel warmer than a few hot radiators and cold floors.

However underfloor heating is very dependent on good insulation underneath.

brightspark

Bigus wrote: »

Google heat loss formula.

I.e. Heat loss is directly proportional to temperature difference .

As regards electric heater efficiency, under floor heating will be more efficient as it heats a much larger area up to a much lower temperature, i.e. Heat loss is dependent on temperature difference so a huge floor heated to 20 degrees C might have the same amount of energy contained heat as a radiator at 65 degrees C , but we both know which will lose the heat more slowly.

Also underfloor heating will result in less room temperature fluctuation, so can be run at a lower room temperature setting , yet feel warmer than a few hot radiators and cold floors.

However underfloor heating is very dependent on good insulation underneath.

And as 2011 has already stated the flooring material will also have an effect, not always positive.

loyatemu

air heat pump will increase the efficiency of electric heating to 300%+ - if you're starting from scratch that's worth considering.

2011

loyatemu wrote: »

air heat pump will increase the efficiency of electric heating to 300%+ - if you're starting from scratch that's worth considering.

That is not correct. As per post #5 you can not break the laws of physics by having a heater that has an efficiency of greater than 100%.

See post #2 for the efficiency formula.

A heat pump can provide a more cost effective heating system which is quite different from a more efficient system.

2011

Bruthal wrote: »

That's because the efficiency is only being measured at the final point. But payment for electricity includes the inefficiencies which are all before the heater element.

The losses you refer to are not electric heater losses so they have no impact of the efficiency of the heaters themselves.

My advice remains the same, don't use electricity to heat a home unless you have no other option. It's simply too expensive.

Bruthal

loyatemu wrote: »

air heat pump will increase the efficiency of electric heating to 300%+ - if you're starting from scratch that's worth considering.

It's not really increasing efficiency of electric heating as such though, as its not electric heating. It's a refrigeration circuit transfering heat from one place (air outside) to another place (air inside). And the transfer mechanism is an electric pump.

And when the air outside is much colder than inside, a higher volume of air outside must move across the evaporator to extract the same heat from it to maintain the temperature inside, so the systems efficiency drops the colder it is outside.

Bruthal

2011 wrote: »

The losses you refer to are not electric heater losses so they have no impact of the efficiency of the heaters themselves.

Electric heating is not 100 percent efficient really though. The change of electrical energy to heat energy in the heater is practically 100 percent efficient. But you have to generate and trasmit the electricity. And that, is what users pay for. No disagreement on anything you posted, I'm just pointing out for anyone reading, that electric heating is expensive for those reasons, which was why I highlighted that part of your post I quoted. I was referring to electric heating being expensive.

loyatemu

2011 wrote: »

That is not correct. As per post #5 you can not break the laws of physics by having a heater that has an efficiency of greater than 100%.

See post #2 for the efficiency formula.

A heat pump can provide a more cost effective heating system which is quite different from a more efficient system.

OK, semantics. If you are heating your house with electricity, a Heat Pump is a better, more efficient option than using direct electricity (e.g. storage heaters). In my house, we obey the laws of thermodynamics!

2011

loyatemu wrote: »

OK, semantics.

I'm an engineer trying to design a more efficient turbine system at present so this is at the forefront of my thought process, apologies I wasn't trying to be smart.

However in the case a heat pump is unlikely to be an option for the OP as the home in question is an apartment.

If you are heating your house with electricity, a Heat Pump is a better, more efficient option than using direct electricity (e.g. storage heaters).

Semantics again but as Bruthal has pointed out a heat pump is not really electric heating even though there is an electrical cost associated with running a heat pump. I accept your point entirely that a properly installed heat pump will heat a home at a lower cost than electric heaters would.

In my house, we obey the laws of thermodynamics!

Sleeper12

loyatemu wrote:

OK, semantics. If you are heating your house with electricity, a Heat Pump is a better, more efficient option than using direct electricity (e.g. storage heaters). In my house, we obey the laws of thermodynamics!

In my house we obey the laws of the wife.

Roen

Could be ****e, but IR heating is another option.

DoozerT6

I'm in a similar position to the OP - I'm an apartment owner, with my only option being electric heating unfortunately. I have storage heaters, which I see as a waste during the day when I'm not there, very expensive to run, and not warm enough on very cold nights. I have also considered installing the newer electric heaters, but am hesitating due to the overall costs.

Would it be any more cost effective to buy (probably two, as I have a large kitchen/living area) oil filled electric heaters and set them to come on at specific times during the day? During the morning before work if I set even just one of them to come on for 30 mins or so they would still be using the night saver rate, but during the evening I would be thinking of setting them to be on maybe between 4.30pm and 10pm. They might be on a bit more at weekends if I'm at home but I could figure that out as I went along. How would something like that compare to storage heating cost-wise?

In all honesty I'm a bit clueless about stuff like this - I just tend to turn things on and hope they work, I don't really know HOW they work, so I appreciate any responses.