Storage heater timing issues - Economy 10 / 7

[jonesyUK]

I am desperately trying to cut our £160 a month electricity bill at the moment. We have a 2 bed semi with no gas and run just 3 storage heaters for the whole house. We have a brand new hot water tank, immersion left on all the time as I understand this to be cheaper in the long run if you have a new tank. Most appliances we run during the night, newly insulated loft, energy saver light bulbs etc. (In short I believe I have trimmed as much excess use as possible)

The problem I have is with our storage heaters. At the moment they come on between 22.00 and 8.00 to store heat. Now e.on tell me that our economy 10 cheap rates run from:

22.00 - 00.30
2.30 - 7.30
13.30 - 16.00

Am I being stupid to think that this can't be right?! And that our storage heaters timing isn't in sync with my tariff. In fact we are not using the 13.30 - 16.00 rate at all. So my questions are:

1. Who do I get in to change the timing of when my storage heaters store heat?
2. Would it not make more sense going on economy 7 as essentially that's what I'm on at the moment, as I'm not using the afternoon cheap rate anyway?

 

[Steve]

It depends how your storage heating is switched.

I'm not sure if its eco10 that isn't approved for storage heating.

You may be better on eco7, though on eco10, you can "topup" the heat in the afternoon for the evening.

 

[Taylortwocities]

Have you got a separate fuseboard for the storage radiators?
How is it fed from the meter?
Can you post a picture of the setup.


I agree, Econ 10 is not really designed for storage rads - its more for all electric house heating systems. Like this http://www.gasapplianceguide.co.uk/heatrae_sadia_electromax.htm

I have a customer with econ 10 and it was costing him heaps.
He had separate timers for the immersion and a storage rad.
The timers were syncronised to only be on at Econ 10 times.
I then found that his Econ 10 meter did not automatically change from GMT to BST so he was using 3 hours a day at peak rate when he thought it was off peak times.

 

[Stoday]

You'll get more heat out of the same size storage radiator on Economy 10 than Economy 7. Apart from the extra 3 hours charging time in 24, you also reduce the discharge time from 17 hours to 6 hours. That adds up to a big performance difference.

Your supplier can arrange for you to have a timed connection that can operate a contactor, if not the full load, to the off peak times. You would then never lose synchronisation.

The times look OK for Economy 10; there is indeed a night peak in the early hours as well as one around 17.30.

 

[nacnud11]

You are going to get a lot of conflicting and confusing information about this as most of the electricity suppliers themselves don't understand economy 10, i am in exactly the same situation and have spent over a year understanding how it all works, im on economy 10 i have storage heaters and have looked into going to economy 7 (economy 10 has high standing charges as well by the way so you will get charged even when you haven't used any electricity). The thing to remember is both economy 10 and 7 is a tariff but there are two ways of using this tariff, you can have a conventionally wired house where everything in the house will use electricity at a reduced rate at the reduced periods or you have a house where the heating (and the imersion) is on a separate circuit (this is more normal on a house with night storage heaters), this circuit is controlled by the electricity suppliers, it is only live when they switch it remotely and in eon's case it is for the periods they have stated, it cant be out of sync with your heaters as they don't have any time controls, they come on when the circuit is live (as long as they aren't switched off. If you give 3 readings for your electricity you definitely have a separate circuit for your heating, day, night and stored heat. Contrary to a reply you have already had, economy 10 definitely is designed for night storage heaters it was introduced because on economy 7 if you use the heat in the afternoon there is none left for the evening. economy 10's advantage over economy 7 will depend on how much time you spend in your house during the day, which is where economy 10 gives you the afternoon boost hours.

 

[Steve]

You are going to get a lot of conflicting and confusing information about this as most of the electricity suppliers themselves don't understand economy 10, i am in exactly the same situation and have spent over a year understanding how it all works, im on economy 10 i have storage heaters and have looked into going to economy 7 (economy 10 has high standing charges as well by the way so you will get charged even when you haven't used any electricity). The thing to remember is both economy 10 and 7 is a tariff but there are two ways of using this tariff, you can have a conventionally wired house where everything in the house will use electricity at a reduced rate at the reduced periods or you have a house where the heating (and the imersion) is on a separate circuit (this is more normal on a house with night storage heaters), this circuit is controlled by the electricity suppliers, it is only live when they switch it remotely and in eon's case it is for the periods they have stated, it cant be out of sync with your heaters as they don't have any time controls, they come on when the circuit is live (as long as they aren't switched off. If you give 3 readings for your electricity you definitely have a separate circuit for your heating, day, night and stored heat. Contrary to a reply you have already had, economy 10 definitely is designed for night storage heaters it was introduced because on economy 7 if you use the heat in the afternoon there is none left for the evening. economy 10's advantage over economy 7 will depend on how much time you spend in your house during the day, which is where economy 10 gives you the afternoon boost hours.

A night storage heater takes 7 hours to take a full charge and is designed to last all day before it needs another charge. Hence economy 7.

Economy 10 is not designed for this. Eco10 is designed for such uses as plain electric heating, where you might start to heat the house at 1:30pm and the heaters would be on solid for a couple of hours while the house warms up, ready for your arrival home. Same applies for the 2:30-7:30 timing - the house is nice and warm for when you wake up. Another use is heat pumps, and electric boilers.

I see your point WRT storage heat running out in the afternoon, but on a properly specced storage heater system this shouldnt happen.

The normal way to do economy 7 is to have all the house switched to cheap rate at the cheap hours, AND have a DNO supplied contactor that will switch on the storage heaters at these hours too.

The DNO may well not supply a contactor on economy 10, since they dont approve it for storage heating.

 

[nacnud11]

From Wikipedia, the free encyclopedia

Economy 10 is the name of a tariff provided by United Kingdom electricity suppliers created in 2004[1]. Similar to the Economy 7 this is designed to be used with storage heaters or warm air heating. In contrast to Economy 7, which only provides off-peak electricity during night time hours, Economy 10 tariffs provide 10 hours of off peak heating split between night, afternoon and evening. The advantage of this scheme is that by matching the storage periods better to the times when heat is required, less heat needs to be stored during the day, when there may be no demand for heating.

you dont agree with this then?

 

[Steve]

you dont agree with this then?

Do you agree with everything wikipedia tells you?

Just what I'd heard thats all.

I'd also assume it costs more per unit off peak too - think about it, the whole reason they make electric cheap between midnight and 7am is because nobody uses electricity then, and the power stations have excess capacity. So they flog it cheap to make people use it. Middle of the afternoon, demand is still quite high, they dont need housands of homes kicking in with eco10 drawing, say, 12KW per house for their afternoon storage heat charge. This is why they dont advertise it. Eco7 is much better for the network.

 

[ericmark]

I may be completely wrong here but I thought these.

Heat exchanger

• ericmark
• 10 Mar 2009
• 2

were designed for Economy 10 and use water not bricks? The one shown was really for normal boilers not electric but there was an all electric one very similar. Main advantage multi heating sources can be used. For example solar. I was considering it for my house hence I had picture.
The one for Economy 10 was similar but with extra immersion heaters.

 

[nacnud11]

you dont agree with this then?

Do you agree with everything wikipedia tells you?

Just what I'd heard thats all.

I'd also assume it costs more per unit off peak too - think about it, the whole reason they make electric cheap between midnight and 7am is because nobody uses electricity then, and the power stations have excess capacity. So they flog it cheap to make people use it. Middle of the afternoon, demand is still quite high, they dont need housands of homes kicking in with eco10 drawing, say, 12KW per house for their afternoon storage heat charge. This is why they dont advertise it. Eco7 is much better for the network.

i agree, it isn't cost effective to offer economy 10 because the 10 hours, on a separate meter are all at night rate, even though they are drawn in the afternoon, however they make up for this by charging higher rates for economy 10 generally and a high standing charge.

 

[stem]

We have a brand new hot water tank, immersion left on all the time as I understand this to be cheaper in the long run if you have a new tank.

I don't know where you got that from. Follow the process.

1. When you use hot water (ie during the day) cold water replaces what you have used, the temperature of the water in the cylinder falls and the thermostat turns on the immersion element that will then use full rate electricity (probably 3 times as expensive as off peak) to reheat it.

2. When you go to bed and have finished using hot water, the tank will be reheated to its max temperature still at peak rate. The insulation will keep the water hot, and so

3. During the night it won't need anymore heat so no cheaper electricity will be used.

End result you are heating all of your water at the most expensive rate.

What you should be doing is heating the cylinder during the off peak rate only, using the daytime rate to top it up for a boost say 30 minutes only if you run out of hot water. If you can get away without the daytime boost I estimate you will reduce your water heating cost by 60%

If you do need a boost and can use the afternoon eco 10 charge that would be better that normal rate.

 

[Stoday]

You should be using two immersion heaters, one high up the tank and the other low down. The lower heater is switched so that it only uses low cost electricity.

The upper heater can only heat a little water at the top because hot water rises and it cannot heat water below its level. So most of the water is only heated by the lower (low cost) heater. If the upper heater is connected to the normal (24 hour) circuits, it automatically operates as a boost only when most of the hot water in the tank has been used.

 

[newbielady]

Just came across this forum and have a question regarding Economy 10.

My in-laws, both pensioners, had electric central heating installed by their housing association last year.

Their storage heaters were removed and replaced with central heating heaters, but they still have their immersion heater for their hot water.

They have had 2 quarterly bills now. The first was over £600 and the latest over £700. Their bills have literally shot up, and I wondered if Economy 10 was really the best tarrif to be on, when they don't have storage heating anymore?

Any advice greatly apreciated!

 

[Hainsey]

I have 3 storage heaters (originally 4 but took one out in living room and use electric fire instead as took up too much space and only heated room in the day when we were out). I also also have a tank with immersion heater. We are on E7.

We only use storage heaters from about Sept/Oct to end of March when we switch them off at the cu.

We pay a direct debit of about £65 a amonth and are always slightly in credit by the end of the month. We have got this down from £85 per month by only using the immersion heater to heat the water early in the morning about 6am before the higher rate kicks in. It also only heats for bout 15-20mins before going back off this gives enough water for washing and shaving and lasts all day & night, when we go back to bed at about 12 the water is still warm. When we had immersion heating water all day our bills were much more.

 

[CAJ]

Hi, I have been finding out about economy 10 as I have two storage heaters in my flat. The heater in the lounge broke earlier this year and I was wondering whether to replace it with an electric heater or stick to storage heaters. I had a long chat with my energy supplier and they tell me that storage heaters are much cheaper to run than electric heaters mainly because they run on off peak hours. The economy 10 or 7 runs on set hours and the storage heaters seems to know when these hours kick in so heat up. On peak costs 12p per unit and off peak costs 6p per unit. You need to check what Watts your applicance is. So my storage heater is 3 watts so it will cost 18p per hour to heat up ( I think that is correct) so for the 10 hours on ecomony 10 it will cost me £1.80 per night. If I had a plug in electric heater running off 3 watts it would cost me twice that amount per hour 36p, £3.60 for 10 hours.

I was told that if I put in those fancy looking electric wall heaters it would cost me as extra £30 a month to run them so about £180 extra for an electric heater verses a storage heater of the same watts over 6 months.


The person whos parents have electric heating system put in will find that heating is more as it is run on peak electricity....I am not sure if you can go onto economy 10 if you don't have stroage heaters...