Dimplex Vs German Ceramic Core Radiators

matelodave

Try doing a proper heat loss calculation for the rooms that your heaters are in - it's not difficult as there are plenty of calculators on the interweb.

Dont just do a height x width x length one use a proper calculator that takes into account the type of construction and composition of the walls, floor and ceiling and whether they are internal or external. The type and size of the windows etc to get the correct heat requirement for the room.

A wet finger in the air guess is likely to get you an undersized heater which will flog it's heart out all day and you'll still be cold.

It does seem that you've managed to convince yourself that spending a silly amount of money on magic heaters that will use peak rate leccy is the way to go despite all the advice to the contrary.

There really isn't much more anyone can say but if you are determined to go down that path please come back in a few months time and give us an honest opinion of your experience.

macman

DaveGain said:

I am also thinking that obviously the night storage need to be on for 7 hours each night to get the heat required for the next day whereas I can just turn the electric on and off as required, surely that is better isn't it?

appreciate everyones comments so far

Once again, no. To heat a room to xC requires ykWh, however it is delivered. Let's assume it needs 21kWh: so your 3kw NSH will need to be on for 7 hours (full charge from cold) to deliver that. Your Elkatherm delivers 1.5kWh, so will need to be on for 14 hours to deliver the same 21kWh. 
If you were on a single rate tariff, it would therefore make no difference. But, if you use E7, your entire NSH charge is delivered at maybe a third of the cost on cheap rate. Forget the supposed inefficiency (which does not exist) and focus on the unit cost.

danrv

DaveGain said:

daytime rates are currently the same as my existing off peak rate which is why I need to get off my tariff, can only do this by changing heating system

Economy 10 by any chance? 
I’m also stuck on it with no other options available. My single storage heater is 10kw and the tariff is extortionate.
Eon have said that they could change to an E7 meter and I can decide the times. Currently 
I have so called ‘cheap rate’ until mid afternoon. Maybe to get the tariff price down I could 
run the heater on E7 instead, assuming the timer can take the power.
If it really needs the 10hrs, I’m back to square one.

DaveGain

macman said:

DaveGain said:

The Elkatherm are not night storage heaters, they are ceramic core radiators, that this the toss up. Whether to go with more efficient night storage or ceramic core radiators.  My old night storage are drawing a ridiculous amount of energy when I look at the kwH per month.  The issue is not that they are losing heat (as I have the afternoon boost) but the amount of energy the current ones are drawing (and therefore my bill is stupidly expensive for the size of house) and being stuck with one energy supplier (as no-others or maybe one other offers the tariff I am on to get the afternoon boost).  The current night storage heaters are over 3kw whereas I have now been quoted 1.6kw heaters on electric and 1.5kw or less on the Dimplex as replacements, so they new ones will obviously be cheaper right?

No, because a 1.5kW heater produces half the heat of your 'inefficient' old 3kW NSH. To produce the same amount of heat will take twice as long, so will use the same amount of electricity as a heater twice as powerful. In fact, rather more, as heat loss must be factored in with the longer delivery period. 1kWh of energy is 1kWh of energy, however it is delivered.
The point about an NSH on E7 is not that it delivers more or less heat, or more or less efficiency, per kWh, but that it runs on cheap rate power that is around one third of the cost of single rate or peak rate power. You don't seem to have grasped this at all.
Your other issue is that you are on an old E10 tariff, or similar under another name. Only the legacy suppliers support these now very uncompetitive tariffs, so you need to move to a competitive E7 one instead, with a change of metering.

Thanks, I completely grasp the idea of the single rate vs the 2 rate tariff, i'm just investigating all options and weighing these up.  I am unable to move to economy 7 as I will lose the afternoon boost and I need that as my current NSHs are cold by the afternoon, thus the need to change.  Unless as said previously I just stick with what I have and have plug in heaters, seems to defeat the wholde point of having heating to me.

danrv

So the reason to change is the same as mine. Very expensive Economy 10 rates.
A competitive E7 tariff and well insulated storage heaters designed for it would be cheaper to run than what you currently have.

DaveGain

danrv said:

So the reason to change is the same as mine. Very expensive Economy 10 rates.
A competitive E7 tariff and well insulated storage heaters designed for it would be cheaper to run than what you currently have.

yes that and the fact that I'm using over 10,000kwh per year for a tiny house seems excessive.  Thanks for your comments.

danrv

DaveGain said:

yes that and the fact that I'm using over 10,000kwh per year for a tiny house seems excessive. 

I use around 8000kwh for three bed semi detached. You’ll be pushing towards 12000+ kWh per year if you go with direct electric heating. 

matelodave

DaveGain said:

danrv said:

So the reason to change is the same as mine. Very expensive Economy 10 rates.
A competitive E7 tariff and well insulated storage heaters designed for it would be cheaper to run than what you currently have.

yes that and the fact that I'm using over 10,000kwh per year for a tiny house seems excessive.  Thanks for your comments.

If your house needs 10,000kwh a year to keep it heated then it really doesn't matter what sort of heating you've got, gas, leccy, oil etc it will still need 10,000kwh a year. It's not actually rocket science, it's just basic physics.

Getting heaters with a lower output will just mean that it never gets up to a comfortable temperature. Installing heaters that use peak rate energy will cost more than heaters that use off-peak energy so you need heaters than can maximise the use of cheaper off-peak energy rates which are usually E7 rather than E10 or other complex metering systems.

The only way to get more heat out than the energy you put in is with a heatpump - mine uses about 4500kwh a year of leccy and produces around 11,000kwh of heat.

Gerry1

DaveGain said:

danrv said:

So the reason to change is the same as mine. Very expensive Economy 10 rates.
A competitive E7 tariff and well insulated storage heaters designed for it would be cheaper to run than what you currently have.

yes that and the fact that I'm using over 10,000kwh per year for a tiny house seems excessive.  Thanks for your comments.

The average annual gas use is 12,000kWh and the average electricity use is 2,900kWh, so your use is well below average.  However, your costs per kWh are likely to be well above average (what are they?), and that's what's really doing the damage.

Assuming it's really impossible to get gas and you don't want to install an LPG or oil system, there's really only one effective plan.

• Forget all about magic dust radiators, they're a snare and a delusion.
• Switch to E7 and arrange the wiring so that the NSHs and lower immersion heater are on circuits switched by the meter.  Make sure the upper (Boost) immersion heater is switched off.
• Get a competitive tariff now that you're not restricted to your legacy supplier.
  
• Turn the NSH inputs to maximum and turn the outputs to minimum each evening before going to bed.  Turn the output to maximum if a room gets chilly later in the day.
• If a room still gets chilly, add another NSH or replace the existing one with a bigger one, and cascade the others to increase the the capacity of each room.  It doesn't have to be new, a second hand one will be fine.  You might even find a free one on Freecycle or Freegle.

DaveGain

Great thanks