Official MSE Economy 7 Guide discussion

Rogbrad

If you have storage heaters and Economy 7 then it's really worth looking at switching to Economy 10.
I lived in a house with E7 storage heaters - I woke up in the morning feeling too hot, and as the evening progressed went to bed with a chill around me.
I installed Ground Source Heating where I am now - it's essentially a big underfloor storage heater - and use E10. We have 3 chunks of cheap rate electricity each day so the house stays at a confortable temperature.

Richie-from-the-Boro

fairyqueen wrote: »

Hi im sorry if someone else has asked this but im on economy 7 and have storage heaters is it normal that my night usage is much higher than my daytime usage

My actual usage in the 2017 - 2018 12 months was

- Day 2,455 kWh = 41.87% Day
- Night 5,864 kWh = 58.13% Night
- Total-pa 8,319 kWh

So yes it needs to be higher in the whole years cycle, as you can see I average 60% night and 40% day over 12 months.

So if your average E7 was ≈ 50/50% over 12 months @ about 4k kWh of day rate and 4k kWh of night rate, a total annual mixed consumption of 8k kWh, and assuming 70+% of the total night rate being consumed in the winter period.

Clearly all homes and usage are going to be different but if you lived in a typical 80's regulation build, refurbished with typical insulation and current double glazed to a B-C EPC rating and using bog standard automatic model cheepo storage heaters @ today's E7 tariff rates it would cost in the region of £7-800 annually, my 2017-2018 personal projection [see above (29th 2017) was £712.96.

You want an average of 21°C in the winter period and you own one big 3.4kW and one middle sized 2.5kW NSH thats a total of 23.8 + 17.8kWh or 41.6kWh of stored heat. That 41.6kWh of stored heat is available for release over the next 17 day hours or the equivalent of a 2.44kW fire at full output for those 17 hours.

Of course there are always odd days when you need complimentary extra heat immediately, and days when your store of heat is never fully depleted, but its not wasted, it remains in the can as existing heat that does not need to be replaced the next night.


A brick is a brick :

- each brick will hold 1.48kWh of cheap heat and depending on insulation will release it over the next 17 hours
-
- each of the (up to 4) vertical 850W elements sits in the gap between 4 of these bricks

- each brick is 230x190x50 - if you divide the total amount of heat you want by 1.48 you know how much stored heat you need
-
- a NSH tin comes in 4 varieties up to a 16 bricker 16 x 1.48kW = 23.8kWh of stored heat
-
- equivalent to a 1.4kW heater permanently supply of 'cheap electrical background heat' 24 not 17 hours per day

If its out of heat by say 5 or 8 or 10pm then its because you have under-specified the tin storage needs and need more bricks or you have the damper open in which case it is not good-radiative but bad-convective.

Placement of a NSH should where aesthetically possible should be direct-line to your self, the benefit of radiated direct heat is much the same as [felt] IR heat. Keeping the living area at say 15°C is from my point of view medically unsafe and socially unreasonable, (2018-19 GOV recommends 18-19°C) it's your house, you decide.

Best of luck !

OPMDaze

Anyone with really old meters it's worth checking what time your cheap rate is starting. Recently found out my meter is running an old time E7 and my cheap rate is 6.30pm to 1.30am. Perfect for me.

stuartindigo

I've been a little bemused by the MSE energy club comparison.

It recommends that I switch to Night OWL V2, and gives an estimated saving of over£440/yr.

There is a "Fair Usage" policy on that tariff which is 60% night usage, and then they will switch you to one of their other tariffs.

When I input my figures, it showed that I was at 70% night usage (over slightly more than a whole year), and when looking at the other tariffs there was no significant saving for me.

Why is this tariff being recommended when it appears that I will not be able to stay on it?

<EDIT>I don't know if it was because of this issue, but this does not appear on my most recent comparison</EDIT>

billieboy_2

Apologies for the length of this.

We have an Economy 7 meter and even though we took out storage heaters and put in oil-fired radiators in the summer of 2017 we have kept this meter. Our usage can be split 2N 11D or 3N 4D or 5N 11D or 3N 4D, etc (quite inconsistent but as much as 6N 24D during Christmas period with extra people and electric heater, electric cooker, etc on a lot). When I do a comparison, I check the tariffs for both Standard meters and Economy 7. Have just done a comparison and got a quote with Yorkshire Energy fixed until Feb 2020:

For Standard meter:

Standing charge 25.24739 (£92.15 pa)
Unit Price per KWH 14.903

For Economy 7 meter:
Standing charge 25.62610 (slightly higher: £93.54 pa)
Day Unit Price per KWH 14.488 (cheaper than unit price for Standard meter)
Night Unit Price per KWH 11.240

All prices inclusive of VAT.

So, based on last year’s usage of 5614 and, say, 20% night usage:

On standard tariff that would equal £836.65 + £92.15 standing charge = £928.80

On Economy 7 tariff that would equal £126.20 night + £650.69 day + £93.54 standing charge = £870.43

Even if it came down to 10% night usage, on Economy 7 it would be:

£63 night + £732.02 day + £93.54 standing charge = £888.56

The energy company's figures for annual usage tally with mine. Was with Oneselect until they went in December.

I’ve always been under the impression that, unless you are using a good proportion of electricity at night, it’s not worth having Economy 7. Am I missing something? Has anyone else found this? Thanks in advance.

ARK5

I can’t quote all my figures but I find the same. I’ve been working out my night vs day consumption over the past three or four years and it is 20-26% night. So I started checking with and without E7 when I compare rates as well. With my last two suppliers (Flow then One Select), it was definitely cheaper to stay with an E7 tariff despite the low night use.

The issue with E7 for me is it’s often inconvenient and a real pain to plan to do my washing and/or drying overnight, and my dishwasher doesn’t have a timer so that’s even worse. Also, I attended a meeting when a fire officer gave a talk in which he said you should never operate these appliances unattended. So I was determined to find a supplier with good rates on a standard tariff so that I can use everything when I want and without worry. Since I changed in November, I am so much happier being able to put the dishwasher on the minute it’s ready and I’m not forgetting about washing which used to get left in the machine for a day or so when I did it overnight!

billieboy_2

Thanks for your reply. I tend to just use the dishwasher overnight, not the washing machine as it's too noisy and bedroom is next to kitchen. Can I ask who you're with now and what happens with your two readings? Do they just add the two together? TBH I don't think the dishwasher uses that much electricity compared to things like the cooker, electric heater, TV etc.

ARK5

billieboy wrote: »

Thanks for your reply. I tend to just use the dishwasher overnight, not the washing machine as it's too noisy and bedroom is next to kitchen. Can I ask who you're with now and what happens with your two readings? Do they just add the two together? TBH I don't think the dishwasher uses that much electricity compared to things like the cooker, electric heater, TV etc.

Hi billieboy. I changed to People's Energy (The People's Energy Company) in November (still waiting for my One Select credit refund!). They had the best rates for me at the time but while I usually don't compare rates and deals again for several months, I am actually going to shop around again shortly when I'm not so busy because their rates are going up in early Feb, according to a recent email. I haven't had chance to do a comparison but I will because it was already quite borderline. I suspect PE won't be your best bet.

I did ask them about the two meter readings thing and they confirmed they just add them together for one total reading. My meter does give that total but I still have to enter the day and night readings separately when I submit online. (As I understand it, all these sites know from your postcode and property number what kind of meter you have so it automatically presents me with two boxes for readings.)

I'm not sure about consumption by different appliances. I assumed because the dishwasher and washing machine heat water and they are on for quite a long time, they would be relatively expensive to run. I will just say that when I took readings after one month on the new tariff and using appliances less overnight, my night use had gone down to 19% and at the most recent reading it was 17%.

Let us know what you end up doing.

MaeveyD

So, if I switch the storage heater on at the wall, and store heat through the night, can I then switch it off at the wall at 7am or whatever and still use the stored heat through the day? Thanks, Maeve

Richie-from-the-Boro

It will come on and off automatically, just leave it switched on. When you no longer need NSH around April / May switch it off till next winter. Turn the input to full and the output to completely off till you find the preference you want.

Your water should continue to heat up all year round. Get the best tariff for E7, get an online account, submit regular meter readings.

Best of luck