Storage heaters vs other electric mediums

stickman

ALL electric element heaters are 100% efficient, all release 100% of the energy put in.
It's up to you if you want to warm a room quickly by using a fan heater of 2kw or warm it slowly (to a lower temperature) with a storage medium holding 2kw.

Above quote taken from Tired geek, many thanks.
The above qoutation is my dilema. All electric house 3 bed semi currently on E7 storage heaters old type not more modern style.
As many learned posters have said all electric heating is 100% efficient, it's how that heat is dissapated which is my problem.
Storage heaters ok but release heat when not home little or no heat on return.
Advice needed on best appliances.
Fan heaters too noisy, have electric bar fire 2x1kw radiant bars which really warms room quickly and keeps it warm as stat kicks in/out as required on what temp I've set at.
However not really cosmetically viable for whole house heating.
I suppose really need instant heat first thing in morning for a couple of hours the same on return from work but for possibly longer time.
Realise it's a big minefield but any advice appreciated.

Thanks

Cardew

It is claimed that modern storage heaters retain their heat better than the old big boxes, and look better. However they will still 'leak' heat during the day when you are out at work.

With storage heating you will be on Economy 7 and get hot water at off-peak rates.

If you decide to ditch storage heating, I suppose oil filled radiators and/or panel heaters will be the best cosmetically.

You can always buy a £20 3kW fan heater for your instant heat when you get up and return from work.

penrhyn

There are also duo heat storage heaters that have an extra heating element that runs on day rate electricity if you need a boost in the evening. They require two feeds though.
http://www.dimplex.co.uk/products/domestic_heating/installed_heating/index.htm

I've no working experience of this type though.

Creda call them Eco response.

stickman

Cardew wrote: »

It is claimed that modern storage heaters retain their heat better than the old big boxes, and look better. However they will still 'leak' heat during the day when you are out at work.

With storage heating you will be on Economy 7 and get hot water at off-peak rates.

If you decide to ditch storage heating, I suppose oil filled radiators and/or panel heaters will be the best cosmetically.

You can always buy a £20 3kW fan heater for your instant heat when you get up and return from work.

Thanks Cardew, was thinking of just a couple of convector / fan heaters for bedrooms and for when I get home. Problem then is what appliance to keep main living room and kitchen area at constant heat level for the last 7 hrs of the day.
With this in mind was wondering if better to come off E7 to std tariff as I use more during evening than the day.

grahamc2003

If you dump the storage heaters and e7, then you'll pay about 2.5 times the cost for each unit of heating. So you can 'waste' quite a lot of e7 heat before it becomes cheaper by paying 2.5 times the cost.

The maths you need to do are something like this

Say you use 100kwh of e7 heating to keep your home warm for a couple of days, cost at 5p/kwh is £5.

Say you only need 60kwh to heat the place with a fan heater when you get home, cost at 12p/kwh is £7.50

so in that example, e7 would be cheaper. I'd say it's cheaper for most people with normal lifestyles, but of course you'd have to estimate for your own circunstances.

Going back to the same example, if 100kWh are needed by modern slime line storage heaters, then you'd probably need about 130kWh of heat put into an old type thick storage heater to get the same temperature when you need it later in the day/evening.

Basically, I'd say it's very likely/possible (depending on your lifestyle) that it will be cheaper to heat at day rates rather than old style heaters, but more expensive to heat at day rates rather than using modern slim line storage heaters.

The difference between old style and modern storage heaters is large and is the difference between a useless heating system and an acceptable heating system imv.

stickman

grahamc2003 wrote: »

If you dump the storage heaters and e7, then you'll pay about 2.5 times the cost for each unit of heating. So you can 'waste' quite a lot of e7 heat before it becomes cheaper by paying 2.5 times the cost.

The maths you need to do are something like this

Say you use 100kwh of e7 heating to keep your home warm for a couple of days, cost at 5p/kwh is £5.

Say you only need 60kwh to heat the place with a fan heater when you get home, cost at 12p/kwh is £7.50

so in that example, e7 would be cheaper. I'd say it's cheaper for most people with normal lifestyles, but of course you'd have to estimate for your own circunstances.

Going back to the same example, if 100kWh are needed by modern slime line storage heaters, then you'd probably need about 130kWh of heat put into an old type thick storage heater to get the same temperature when you need it later in the day/evening.

Basically, I'd say it's very likely/possible (depending on your lifestyle) that it will be cheaper to heat at day rates rather than old style heaters, but more expensive to heat at day rates rather than using modern slim line storage heaters.

The difference between old style and modern storage heaters is large and is the difference between a useless heating system and an acceptable heating system imv.

Great analysis, spot on. However re E7 vs std rate, Surely even with the new style storage heaters the saved heat will still not be enough to keep rooms warm for the evening period 7 hrs. Really need less of heat in mornings but more heat in evenings. Realise E7 on cheap rate for 7 hrs but really only require mybe 2 hrs in morning rest of day at work.

grahamc2003

stickman wrote: »

Great analysis, spot on. However re E7 vs std rate, Surely even with the new style storage heaters the saved heat will still not be enough to keep rooms warm for the evening period 7 hrs. Really need less of heat in mornings but more heat in evenings. Realise E7 on cheap rate for 7 hrs but really only require mybe 2 hrs in morning rest of day at work.

If correctly sized for your room, and you have decent insulation, know how to use your heater correctly (and I'd say most don't, with incorrect advice frequently given on these boards) then a modern storage heater should supply all the heating requirements down to 0C outside. You should rarely need to use any supplementary heating (unless you like it above 20C, your insulation is poor, or your storage heater capacity isn't enough, or the weather drops below 0).

The room will be warm anyway for the morning 2 hr period, so no extra heating required there. Probably warm you you get home from work too, and when it starts to get too cool, you simply set the output up, and the stored heat will come flooding out.

It's a no brainer anyway to replace you old storage heaters. In the summer, you can pick up modern slim lines off ebay for next to nowt, and they are easy to disassemble and assemble. Nothing to lose except a bit of petrol and a few hours work.

If you're not on gas, the look into the rhi subsidy - you could get a heat pump/pellet burner paid for.

malc_b

stickman wrote: »

Great analysis, spot on. However re E7 vs std rate, Surely even with the new style storage heaters the saved heat will still not be enough to keep rooms warm for the evening period 7 hrs. Really need less of heat in mornings but more heat in evenings. Realise E7 on cheap rate for 7 hrs but really only require mybe 2 hrs in morning rest of day at work.

Don't forget that your house has heat storage in its structure. Typically the saving for heating 16/24 instead of 24/24 is 15-5% of the 24 cost. If you check out the thread on Energy myth-busting: Is it cheaper to have heating on all day? you'll find a lot of people report it does save them money, contrary to what the gov advice says. Although they are talking about gas/oil rather than E7 the principle is the same and the reason people see a money saving is that the heat saving for running 24hr is quite often less than the efficient difference between a steady low heat vs a few mad hours of mega heating. The better insulated your house is the less (percentage wise) is the difference between 24hr and not.

So E7 will always be cheaper than std rate heating, even if you have to top up E7 on std rate as the E7 is giving you a background base load to keep the house structure warm.

If this doesn't sound right to you consider what happens if the house is 20C inside and the weather 0C outside. The loss to the outside is (approximately) the same as when the heating was on since the temperature difference is the same. So where is this heat coming from? The house structure. And even if the heat is off for 8 hrs the house is unlikely to fall to 0C so all that the structure is heating the house, and creating a heat debt you have to pay back.

stickman

Just to say thanks to all of you who replied, great advice have learned a lot.
Will be looking for some new style storage heaters,and staying on E7 as a result.

Thanks again

Naf

I calculated it out based on the capacity of my storage heaters. The living room has a 24kWhr model so uses a maximum of 24 units overnight. I also have a 3kW convector heater. My day rate is roughly double the night, so needing the convector for 4 hours a day is the tipping point where I turn off the storage heater and just use the convector.

It's worth considering something like I did there, as well as how much heat your storage heaters hold. I fond that mine are mostly cooled by the evening, so when wife & kids are away they get turned off completely and i rely solely on the convector when I'm home (by the time I'm home, storage heaters would be much cooler, that heat having been wasted when I'm not around). If your storage heaters hold enough heat so the house is still warm enough later on, then they will usually be cheaper. If they really are too cold by then so you're using the convector as well anyway to boost the temperature, then consider the prices based on average use.

Generally the convector will give a fast, even(ish) boost of heat which you'll feel rapidly; a fan heater will move lots of air fast, and fast moving air cools quickly so it's overall heating effect is lessened, but those directly in front of the blower will feel warmer; oil rads provide constant, even heating but won't be felt as obviously all the way across the room (less air moving) but they take time to eat themselves up before heating the room.
I prefer convectors.

malc_b

You're assuming that your 24kWh storage heater always takes 24kWh. It can't work that unless your E7 heating is almost never good enough. The heat loss from a room/house depends on the outside temperature, so at 10C outside it is half what it would be at 0C. I think for storage heaters that means they stay warmer longer and so are still warm at night (internally) and don't take as much to heat up.

My mother has E7 and she has an external sensor that adjusts the night charge time. That based on the expectation that a cold day follows a cold night.

And we come back to the principle that your house stores heat. You have to heat the structure when you heat a room. If you don't you'll have cold walls (same as outside temperature) and condensation.