Economy- tariff and huge bills - help to undestand please

Buka

Hello all,

You can read the whole story below, but I think at this stage our question is simple:
is it possible to "store" energy during cheap off-peak hours for heating purposes during the day with:
Boiler Heatrae Sadia Amptec C900 and Heater Santon Premier Plus 210L.
We don't have any additional night storage heaters, only room thermostat for times temperature control and normal radiators.

Thanks!


Full post below:

We would very much appreciate your help here to understand our setup and eventually why our bills are so big. I tried to google these things and found a number of useful threads (e.g. this one forums.moneysavingexpert.com/showthread.php?t=5304726) and also learned about some useful devices (e.g. home energy monitor), but I don’t have anything like that now.

In November we moved to a flat which is only supplied with electricity and has Economy 9 meter (EDF). Never before have I lived in a flat with no gas, neither Economy 7, so this is even one step further with the Economy 9.
The practical problem is that during colder winter month (Jan-now) when we used heating we noticed that the bills became very high, e g 150 pounds/month compared to <50pounds in December. The question here is not about tariffs but rather if we’re using the heaters/boiler etc correctly.

We noticed that during the first month here (no heating used) our average daily consumption was 8kWh (Rate1) and 7kWh (Rate2), while during Feb/March it came to 25.8 (Rate1) and 7.7 (Rate2). So Rate1 increased more than 3 times and Rate2 daily usage only changed a bit. We’re very confused as our understanding was that the heater should “save” energy during heating off-peak times so that we can then use it throughout the day, hence we expected the Rate2 consumption to go up, but not so much the Rate1. (EDF bills us as Rate1=more expensive and Rate2=cheater).
The temperature in the flat is controlled with a thermostat which is programmed to only come up for an hour in the morning (7:00-8:00) and 4 hours in the evening (18:00-22:00) as we’re a working couple, although it is on for more time over the weekends. All the radiators in the flat are normal in a sense that there aren't any night storage heaters.
The problem is being complicated by the fact that we don’t have access to the meter ourselves and can ask for and get readings at daytime only as there’s no caretaker in the building after 6pm.
Next to the boiler we have 4 switches for general control, this is how we keep them in winter months:
Boiler ON
Boiler Control ON
H/W Boost OFF
H/W Off Peak ON
Heating Off Peak ON
When we didn’t use heating regularly, the “Heating Off Peak” was in OFF position.

While we don’t make a habit of checking when the boiler is ON, today we have been regularly checking and noticed that when we turned the thermostat up at day time the boiler came on. The thermostat was on for about 2 hours between 13:00-15:30 (which should be “off peak heating” time on Economy 9), but the meter readings seem to indicate that Rate1 went up 13kWh and Rate2 only by 3kWh (I had to ask our caretaker to take several readings), which makes me think that the boiler is connected as a normal appliance and hence can’t utilise Economy 9 cheap day heating hours. It also might suggest that there was no energy “pre-saved” for some reason.

I would appreciate people’s advice on the following:
- do you see anything wrong with how we use the switches?
- is my assumption correct that the main energy consumption increase in winter days should come for Rate2 (or, rather, cheaper rate)?
- can it be that Rate1 should actually be the cheaper rate rather than Rate2?
- can it be that the heater for some reason is incorrectly wired into the meter? Or maybe the “heating Off Peak” switch is “the wrong way around”? As far as I understand the whole thing was reinstalled by professionals in 2012 so there shouldn’t be a reason to suspect this..
- is hot water heating/storage separate from heating?
- would appreciate if someone can explain what are all the tanks and controls we have and how to use and look after them. For example, we have a large tank, SANTON heater (Premier Plus 210l), supposedly it has 2 compartments (I thought one for saving energy off peak, and one for burst), but is this actually correct and how does it work? Is this only for H/W or does it help with heating too?

I'm beginning to think that all our heater and tanks only save hot water and there might be no way to save energy for heating.. Or maybe the same hot water used for heating too?

I can list our the different components below:
Boiler Heatrae Sadia Amptec C900
Heater Santon Premier Plus 210l
2 small vessels (~8l each), one of them is red with a pressure indicator above it
Grundfos pump
(other small bits)

As a new member I can't seem to be able add links (and hence pictures), but you can copy/paste into your browser:
dropbox.com/s/upqbj02xxhuxx1n/IMG_4196.JPG?dl=0
dropbox.com/s/dt4d2fxltm8z0vk/IMG_4199.JPG?dl=0
dropbox.com/s/8v4aag9sf699ev8/IMG_4200.JPG?dl=0
dropbox.com/s/z30y6lj1hsvbklj/IMG_4201.JPG?dl=0
dropbox.com/s/y93i8a3q70hfdj0/IMG_4206.JPG?dl=0

Thanks in advance

Richie-from-the-Boro

The Amtec is a 9kW wet central heating [radiators or underfloor] and hot water supply and possibly the most expensive form of electric heating known to man. I have no experience of running them but suggest that others in your building with the same set up might have more experience and ideas - best of luck.

Buka

Anyone? this is really our question now:

is it possible to "store" energy during cheap off-peak hours for heating purposes and use it during the day with:
Boiler Heatrae Sadia Amptec C900 and Heater Santon Premier Plus 210L.
We don't have any additional night storage heaters, only room thermostat for times temperature control and normal radiators.

macman

E9 is a new one on me (what are the cheap rate hours on it?), but from your description of the system, the only heat you can produce and store overnight on cheap rate is hot water in your hot water tank-you can't store hot water for the CH circuit which is completely separate. However, in the months when the CH is on, by far your greatest usage of electricity would presumably be on the peak rate, during mornings, daytime at weekends, and evenings. E7 is typically cheap rate from midnight to 7am, which is why it is suited to NSH's. I don't know which extra 2 hours you get on E9? The extra cost of all this on peak rate would be far greater than the cheap rate saving on hot water, since space heating is by far the largest part of your total usage.
Wet CH using an electric boiler is a very expensive means of heating and hot watering a property. But doing the majority of that heating on peak rate is completely crazy (if that is what is happening, as I don't fully understand this system). If you are stuck with an electric boiler, then you need to be on a single rate tariff and metering.
The other downside is that you will have a very limited supplier base with E9-do any other suppliers even support it? E10, for example, has only about 4 suppliers
PS: The Santon is simply an unvented hot water tank that stores and supplies hot water under mains pressure. It has nothing to do with your CH system at all.
One final point-for your bills to triple during the winter months is not unusual, as you can expect to use up to 80% of your annual energy usage during the coldest 3 months when the heating is on. Your issue is the kWh rate you are paying for that usage. What you really need are a full years kWh figures, and the usage split on each rate, which is difficult if you only moved in in November. Calculate your approx annual total based on a month's usage when the heating is off, and work out the annual cost, or ask EDF to estimate it. Then use any comp site to compare what the same total usage would cost you on a single rate tariff.

Buka

macman wrote: »

E9 is a new one on me (what are the cheap rate hours on it?)

Thanks for your comments macman.
these are the hours and prices for e9 (it's only extra hours for heating and HW):
power 16.57p
heating 6.42p
standing charge 18.90p
Heating&HW:
-7 hrs between 20:00-07:30 (maybe 2hrs 20:00-24:00 + 5hrs 00:00-7:30)
-2 hrs between 13:00-16:00
Everything else:
-Off-Peak 23:30-06:30, Peak 06:30-23:30

same is confirmed here forums.moneysavingexpert.com/showthread.php?t=5304726

You're correct there's pretty much no flexibility of tariff/supplier with the current meter, but I thought since it's not obviously very expensive tariff (compared to e.g. EDF E7 tariffs), we can see how it goes first before dealing with the hustle of changing the meter (and potentially a lot of other things).


While what you're saying confirms what we see (that all our heating over the winter probably got charged on peak rates), i'm confused because we have a switch "heating off peak", what would that be for? I'm planning to try to call Heatrae sadia support and ask them these questions.. (they took over Santon heater too).
I also talked to someone from our local Council (energy efficiency department) yesterday and they said that looks like this cylinder can produce heat too and the heat release should be controlled by a room thermostat. If that's the case- maybe our thermostat isn't connected correctly? as it just seems to turn the boiler on.

Another q - should the boiler be able to use the 9 hours of off-peak that come with this tariff? E.g. if we turn the heating (through the boiler) on between 1pm and 3pm - shouldn't it be charged at off-peak rate? From looking at our meter readings it seems it's still charged at peak rate (rate1)..

Rubidium

Buka wrote: »

Anyone? this is really our question now:

is it possible to "store" energy during cheap off-peak hours for heating purposes and use it during the day with:
Boiler Heatrae Sadia Amptec C900 and Heater Santon Premier Plus 210L.
We don't have any additional night storage heaters, only room thermostat for times temperature control and normal radiators.

Yes the Amptec C900 9kW electric heating boiler can be installed to provide central heating and domestic hot water in conjunction with an indirect hot water storage cylinder i.e. your Stanton Premier Plus or if preferred, to provide heating only with domestic hot water being supplied by a direct hot water storage cylinder.

The Stanton Premier Plus is a 210 litre heat store. When you draw water from the hot tap, cold mains pressure water passes though a coil in the heat store and the water comes out hot. In a similar way the stored water can be circulated around radiators to heat the property. Obviously any heat taken from the heat store has to be replenished and this should be done using your cheap rate E9 hours although you can boost this during peak rate if required.

As stated electric heating is the most expensive to run, so you need to learn how to use if correctly.