Please need help about what to do with economy 7

andyc58

Hi people I live in a ground floor flat with my girlfriend. I have only electricity not gas. I have a storage heater in front room and bedroom. Also I have a expansion tank that heats up. Not sure how that works but anyway. Im on economy 7 but I have got rid of the front room storage heater because it was rubbish and I have brought an oil filled radiator that works fine. the problem I need help with is.
Do I get rid of other storage heater in bedroom and get off economy 7 as I don't use the cheap rates at night for washing machine. Or stay with economy 7 because of my hot water tank.
Any help on this would be great as im paying 18.70 pkwh and if I change I could get it for 13 pkwh.

James01

Just see how much you are using through the night and if it's just a small percentage of your total use then it will be worth switching. We switched a couple of years ago as we were only using about 15% through the night and hardly anything in the winter. We have found going to a single tariff much cheaper.

andyc58

James01 wrote: »

Just see how much you are using through the night and if it's just a small percentage of your total use then it will be worth switching. We switched a couple of years ago as we were only using about 15% through the night and hardly anything in the winter. We have found going to a single tariff much cheaper.

this may sound stupid but how can I tell how much I use at night. the only thing that will be using economy 7 at night is my water tank I think

victor2

andyc58 wrote: »

this may sound stupid but how can I tell how much I use at night. the only thing that will be using economy 7 at night is my water tank I think

Your most recent bill will show what your usage has been on each rate. Your winter usage (when the heating is on) will favour economy 7 in comparison to summer, so if that isn't working out to your benefit, there's little chance it will in the warmer months.

andyc58

im on a key payment meter so I don't know what I use on each rate.im just not sure how much my water tank uses at night

[Deleted User]

andyc58 wrote: »

im on a key payment meter so I don't know what I use on each rate.im just not sure how much my water tank uses at night

prepay electric shows the day kwhrs use on screen "H" and the night on "J"

andyc58

Yes I understand that but. What I'm worried about is heating my water up via immersion heater on my cylinder when I'm not on e7. The cylinder only has one immersion at the bottom so it don't have a boost switch on it. It says it's 3kw so if I go to standard meter and pay 13pkwh that would be 39p per hour. I'm not sure how long it would take to fill my tank.

What I'm trying to say is I'm on 18.7pkwh now. If I change to standard and go on 13pkwh as I'm using electric in peak times. The money I would save by being on lower rate would running the cylinder tank everyday take the money I'm saving if you know what I mean ???

Richie-from-the-Boro

andyc58 wrote: »

Yes I understand that but. What I'm worried about is heating my water up via immersion heater on my cylinder when I'm not on e7. The cylinder only has one immersion at the bottom so it don't have a boost switch on it. It says it's 3kw so if I go to standard meter and pay 13pkwh that would be 39p per hour. I'm not sure how long it would take to fill my tank.

What I'm trying to say is I'm on 18.7pkwh now. If I change to standard and go on 13pkwh as I'm using electric in peak times. The money I would save by being on lower rate would running the cylinder tank everyday take the money I'm saving if you know what I mean ???

You had an E7 heating system and an E7 tariff. An E7 system delivered stored room and water heat during the night at about 30% of the price of your day time electricity prices. You switched off the cheap heat storage in your living area and use an oil-filled at 3 times the price. A small 115litre will cost about about £1.20 to heat from cold by [100% efficient] electricity. Single circuit / single element cylinders were never used as part of an E7 install, so must have been a bodge with bad insulating efficiency and are normally unheard of these days.

18.7 x 6.019 = 112.5p
13.0 x 6.019 = 78.2p

NOTE: All calcs at 115 litre tank [100% leccy - 6.019] [85% Oil - 7.08] [70% Gas - 8.599]

andyc58

Richie-from-the-Boro wrote: »

You had an E7 heating system and an E7 tariff. An E7 system delivered stored room and water heat during the night at about 30% of the price of your day time electricity prices. You switched off the cheap heat storage in your living area and use an oil-filled at 3 times the price. A small 115litre will cost about about £1.20 to heat from cold by [100% efficient] electricity. Single circuit / single element cylinders were never used as part of an E7 install, so must have been a bodge with bad insulating efficiency and are normally unheard of these days.

18.7 x 6.019 = 112.5p
13.0 x 6.019 = 78.2p

NOTE: All calcs at 115 litre tank [100% leccy - 6.019] [85% Oil
- 7.08] [70% Gas - 8.599]

If you was me would you swap to standard or not

andyc58

It says on my cylinder it's a combination. So I'm not even sure if it's on e7. Don't matter what time of day I use hot water I can hear water in the tank filling up again

victor2

andyc58 wrote: »

It says on my cylinder it's a combination. So I'm not even sure if it's on e7. Don't matter what time of day I use hot water I can hear water in the tank filling up again

Of course the water tank replaces the hot water you've taken out with cold water from the supply, no matter what time of day it is. The question is when does the heating element switch on? Is it timer driven, or connected only to the economy 7 off peak supply somehow?
Is the hot water heater on 24/7 and controlled by its thermostat? In which case it will kick in whenever the water temperature demands it, regardless of the economy 7. Look at your meter just after you've drawn off some hot water outside of the economy 7 cheap rate hours. If the meter is showing a considerable increase in usage, then your hot water heater is probably using it.