storage heaters/electric central heating or gas?

Graham1

One thing to remember on the storage heaters is the "input power" or similarly labeled control operates a small thermal cut-out which controls how hot it makes the storage bricks during the night. So the consumption will only be the product of night rate hours x Kw rating if this control is set to a maximum. Otherwise it can be less. Best way is to take a meter reading last thing and night and first thing in the morning and adjust for other big night-time consumption items like an electric hot water heater.

Cardew

seeking2save wrote: »

No subjective opinions - I've been poring over spreadsheets the last few days.

According to my calculations, storage heaters are more expensive simply because they use more kWh of electricity (particularly on Economy 10), whereas you can control the hours that non-storage heaters are on.

My calculations in summary, monthly electricity costs,using the heater kW sizes recommended by the manufacturers plus an immersion heater @3kW (and Southern Electric green energy tariffs):

3 Dimplex storage heaters (total 5.95 kW)+ one panel heater (1.5kW) + Economy 7:
Off-peak kWh = 1444 * £0.0408
Peak kWh = 182 * £0.096
Service charge = £5.50
Total = £82

3 Dimplex storage heaters + one panel heater + Economy 10:
Off-peak kWh = 2092 * £0.0508
Peak kWh = 75 * £0.0869
Service charge = £4.67
Total = £117

4 Kalirel heaters (total 4.25kW) + Economy 10:
Off-peak kWh = 545 * £0.0508
Peak kWh = 399 * £0.0869
Service charge = £4.67
Total = £67

Being new to all this electric heating stuff, I'd welcome second opinions on the calculations - I don't want to spend loads of money on a new heating system, only to find my calculations were wrong!

I'd prefer modern heaters over bar fires / simple fan heaters (a) because the latter don't have thermostats (at least they didn't in my grandmother's day), (b) modern heaters look better and (c) bar fires are a safety hazard.

I don't wish to be unkind but the principal assumption(in bold) on which you base your calculations(as opposed to your arithmetic) is simply unsupportable.

The first thing is that for all practical purposes all forms of electical heating are 100% efficient in turning electrical power into heat.

You have used 3 different sets of figures for power consumed. 1,626kWh, 2,167kWh & 944kWh(for the Kalirel).

They will produce heat in exactly that ratio i.e. 1626:2167:944

There is clearly a factor of any storage heater 'leaking' heat during the day but using manufacturers figures to calculate that a Kalirel heater can produce - from 944kWh - useful heat equal to 2,167kWh from an E10 storage heater system is again simply unsupportable.

Incidentally I have not seen a fan heater produced in the last 20 years that doesn't have a thermostat - and produces instant heat. Or, if you are set on radiators using peak electricity, simple oil filled radiators will cost a fraction of the installation costs.

if you need some independant advice, why not contact the Energy Saving Trust?

samtheman1k

Have any of you guys looked at the Gledhill Electramate?

http://www.gledhill.net/water-storage/ws-index.htm

This is basically a wet central thermal store that heats up using E10. This is then plumbed into a standard radiator central heating system. During the off peak tariffs, the thermal store is heated up and during the on peak times, the hot water is distributed throughout the normal radiators.

I think this would be more efficient than storage heaters as the hot water is stored in an insulated tank, and thus will stay warm throughout the day (when you are at work), ready for use in the evening.

They obviously has the cost of installing radiators and pipes, but may be an option for those off the mains gas.

Cardew

samtheman1k wrote: »

Have any of you guys looked at the Gledhill Electramate?

http://www.gledhill.net/water-storage/ws-index.htm

This is basically a wet central thermal store that heats up using E10. This is then plumbed into a standard radiator central heating system. During the off peak tariffs, the thermal store is heated up and during the on peak times, the hot water is distributed throughout the normal radiators.

I think this would be more efficient than storage heaters as the hot water is stored in an insulated tank, and thus will stay warm throughout the day (when you are at work), ready for use in the evening.

They obviously has the cost of installing radiators and pipes, but may be an option for those off the mains gas.

There have been a number of posts on the pros and cons of 'wet' storage heating systems, with some interesting and informed contributions especially from 'Peat'

From what I have gathered these have advantages over the conventional storage heating systems, but as you indicate are considerably more expensive to install.

See http://forums.moneysavingexpert.com/showthread.html?t=73072&highlight=wet+storage

Also do a search for 'wet storage'

fatpoo

Apologies if i sound silly; i have a freezing cold, fairly large bathroom that needs heating. There is no GCH. Elsewhere in the flat i have storage heaters on Econ10 I believe. I have just purchased a 1.5KW Creda panel heater with a timer.

What is the best way to set this up for the most economical way of heating the bathroom for most of the day? between 7.30am and midnight? Do i have any options? can i set this uo to use the Econ10 heating tarrif? How much is it likely to cost to run? I dont need it like a sauna just an ambient temperature when i take the throne.

Any help will be very helpful

punamulta

consider a heat pump, I have a couple of these which are aircon in reverse, you refrigerate the air outside and pump the residual heat indoors. they are extremely efficient converting 1kw of electricity into up to 5kw of heat. these are are used in scandinavia, canada and new zealand, the UK as usual is slow on the uptake of new technology. although the festival hall in london had a water source system using the thames when it first opened in the 1950's. this site explains better than i can how they work. prices have dropped recently with imports from china.http://www.bdt.co.nz/comfortmaster/info_buyer.asp

here is a uk supplier but shop around or haggle. http://www.iceenergy.co.uk/

Chrislincs

Hi - new to site . Have been worrying that when we come to sell in 2 yrs. our storage rads will put folk off, so investigating alternatives, in a gasless zone. From this and other threads online it would seem that electric CH is expensive to install and run, not to mention the disruption to every room. That would go for any wet system, I guess.
New to me is E10. The hours seem great, although logic tells me more hours costs more dough. Maybe Cardew, or someone else in the know, could tell me if the 3xday heating would mean being able to run on a lower input yet maintain level temp. thereby keeping costs down. E10 has the advantage that many other high use facillities like showers, irons, even the oven could be run at lower cost if timed right, presumably? We already run the washer, dishwasher, etc. at night, but the thought of using them in the afternoon without counting the cost when I have the grandchildren staying is great.
Yes Punamulta, heat pumps are ideal - but prohibitively priced at the moment, which is a shame cos I'm a greenie through and through.
Ours is a sprawling 30's detached bungalow, which I have insulated, double glazed and got solar water heated, but is still failrly expensive to run. Any tips would be much appreciated. In its favour I support SHs for the fact that I have had some for over 30 yrs, and never needed a service, replacement boiler, had leaks, air locks or any other problems, so probably they are even stevens on overall running.

Cardew

Chrislincs wrote: »

Hi - new to site . Have been worrying that when we come to sell in 2 yrs. our storage rads will put folk off, so investigating alternatives, in a gasless zone. From this and other threads online it would seem that electric CH is expensive to install and run, not to mention the disruption to every room. That would go for any wet system, I guess.
New to me is E10. The hours seem great, although logic tells me more hours costs more dough. Maybe Cardew, or someone else in the know, could tell me if the 3xday heating would mean being able to run on a lower input yet maintain level temp. thereby keeping costs down. E10 has the advantage that many other high use facillities like showers, irons, even the oven could be run at lower cost if timed right, presumably? We already run the washer, dishwasher, etc. at night, but the thought of using them in the afternoon without counting the cost when I have the grandchildren staying is great.
Yes Punamulta, heat pumps are ideal - but prohibitively priced at the moment, which is a shame cos I'm a greenie through and through.
Ours is a sprawling 30's detached bungalow, which I have insulated, double glazed and got solar water heated, but is still failrly expensive to run. Any tips would be much appreciated. In its favour I support SHs for the fact that I have had some for over 30 yrs, and never needed a service, replacement boiler, had leaks, air locks or any other problems, so probably they are even stevens on overall running.

Welcome to the forum.

You are quite right about the prohibitive cost of installing Ground Source Heat Pumps. In any case these are better suited to under-floor heating as the water is not normally hot enough for conventional radiators.(or get much larger radiators)

I assume penamulta is talking about air source heat pumps which have come down in price lot recently. However these are small units that are more suited for heating a room; and conventional wisdom is they are better suited for warmer climates than UK. In any case getting 5kWh heat output for 1kWh input would be exceptional; 3 to 4 times would be a more realistic figure.

As for E10 you would use it in exactly the same way as E7 but have the additional 3 hours during the day to top up; and of course take the opportunity to use the heavy consumption appliances(dryer etc) in that 3 hour period.

I understand that some utility companies seem reluctant to offer E10; presumably as it needs a new meter. Someone did post on here that they cannot refuse to supply E10 although I have no idea if that is true. In any case they could always charge you 20p/kWh to deter you!!

If you do go to E10 you will need to do quite a bit of research ‘manually’ as the on-line comparison networks don’t cover E10 – might be worth ringing them.

Some while ago someone posted their E10 prices on this forum and all of the prices – including the 7 hour period and daytime rates were higher. If you look at Post #55 in the figures he uses E10 is 1p/kWh more expensive(for all 10 hours) than the E7 rate.

So you would need to make assumptions on how much electricity you woul use in the extra 3 hours and do your ‘sums’ carefully. No such thing as a free lunch?

P.S.
You are also quite right about the 'hidden' saving of SH not needing servicing every year.

punamulta

Ulkoyksikkö model
MUZ-FD25VAH
Lämmitysteho heat (kW) 1,5-6,3
COP (W/W)
5,25
just for information above is the spec for the Nordic Mitsubishi heat pump, which works fine down to minus 15 deg c

pdf in english http://www.latcomfort.lv/files/IntroductionMSZ-FD_sep07.pdf

Cardew

punamulta wrote: »

Ulkoyksikkö model
MUZ-FD25VAH
Lämmitysteho heat (kW) 1,5-6,3
COP (W/W)
5,25
just for information above is the spec for the Nordic Mitsubishi heat pump, which works fine down to minus 15 deg c

pdf in english http://www.latcomfort.lv/files/IntroductionMSZ-FD_sep07.pdf

I think we might be at cross purposes here. I am not sure what you are suggesting.

The models obviously have a great spec.

Far better than the one I have in a warm climate abroad!!

However those models are designed to heat a single room, not CH a house unless several of them are built in during construction. Each needs a big box outside.

The model you quote has a maximum output of 6.3kW.

What a quick glance of the specifications doesn't show is a graph of output against outside temperature.

The COP* of 5.3 you quote it will of drop off as the temperature decreases and at the -15C they quote I suspect it will be about 1.5 at best - I read the theoretical point at which unity is reached is -18C.


I found this quote from an independant source:

The technologies are developing rapidly: COPs (coefficient of performance) have risen from COP=3 to COP=4 or even COP=5 over the last five years. Heat pumps are now becoming popular choices for home-heating as well as for cooling — especially in areas with less severe winters.
Those buying air-source heat pumps should look closely at its COP, the outside temperature range in which that COP is effective, the cost of installation, how much heat it can move, and how much noise it generates.
Air-source heat pumps do not work well when temperatures fall below around −5°C (23°F).
Ground-source heat pumps typically have higher COPs than air-coupled heat pumps,

Even your link for New Zealand states:

Mitsubishi Electric air conditioners (or heat pumps) are capable of transferring up to 4kW of heat into a space while only consuming 1kW of electrical energy. This makes them extremely energy efficient. The energy efficiency of a heat pump decreases as the temperature difference between inside and outside becomes greater, but it typically provides 3 or more times as much heat as a normal electric space heater would provide with the same amount of electricity input.

What would the figure be in UK I wonder?

What they are ideal for is, say, a conservatory; but not practical to convert a house to fit them.

* For those unfamiliar with this term, COP = Coefficient of Peformance is the ratio of output to input power.