Economy 10 and 3 phase - feasible or not? ..CONCLUSION: Yes but E7 simpler & cheaper

Former_E.ON_Company_Representative:_Malc

Hi FAI

The meter operators are the guys who fix, install and replace meters on behalf of the suppliers. Contact details for your meter operator may be on your bills.

If it's actually Economy 10 that's fitted, there's only one tariff we offer although the individual prices are regional.

I'll be happy to let you know the prices but MSE don't like me posting this sort of detail on the open forum. Just drop an email to the address in my Profile and I'll be happy to let you know.

Sometimes, Economy 10 is used as a generic term to describe a range of Restricted Hour Tariff (RHT) meters. These meters are set up to give customers cheaper electricity at some time during every 24 hour period.

As Terry says, there are different variations of this type of meter depending on the region. They have different switching times and different rate bands.

It may be, what you eventually have installed is a version of Economy 10 but which is actually RHT.

Again, we'll only offer the one tariff for this type of meter. However, the actual tariff will depend on which version of the RHT is fitted.

Sorry this is a bit vague but hope it helps a little.

Malc

FAI

Thank you everyone for your helpful replies.
I have now learned enough about E10 meters and tariffs to make my decision.

I am going to ask for a phase 3 Economy 7 meter, on my current tariff (Scottish Fixed Nov 2014). Thus tariff is effectively 111.22p.a. + 11.444 p per kWh or 6.042 p per kWh overnight.

This will cost me £1,256p.a. for 10,000kWh - the same as the non-Economy 7 version of this tariff- if I use 10% of my power overnight. For any additional overnight usage my bill reduces.

The reasons for this are:
- The house technology design (warming water in large buffer tanks for subsequent use) lends itself to overnight power usage.
- E10 it too restrictive (few people provide it and even fewer know about it) and I want to be able to switch supplier easily.
- The little I can find out about E10 tariffs leads me to believe I would not make a saving.
- E7 is straightforward. The tariffs are readily published.

Thanks again all.:T

HappyMJ

FAI wrote: »

Thank you everyone for your helpful replies.
I have now learned enough about E10 meters and tariffs to make my decision.

I am going to ask for a phase 3 Economy 7 meter, on my current tariff (Scottish Fixed Nov 2014). Thus tariff is effectively 111.22p.a. + 11.444 p per kWh or 6.042 p per kWh overnight.

This will cost me £1,256p.a. for 10,000kWh - the same as the non-Economy 7 version of this tariff- if I use 10% of my power overnight. For any additional overnight usage my bill reduces.

The reasons for this are:
- The house technology design (warming water in large buffer tanks for subsequent use) lends itself to overnight power usage.
- E10 it too restrictive (few people provide it and even fewer know about it) and I want to be able to switch supplier easily.
- The little I can find out about E10 tariffs leads me to believe I would not make a saving.
- E7 is straightforward. The tariffs are readily published.

Thanks again all.:T

That's a good tariff and it will also encourage you to use more units at night such as those for heating water....and maybe some overnight washing/drying etc...at night if you did want heating you could just use some cheap electric convector heaters for some spot heating in the rooms that you are in without it costing too much. Hopefully when smart meters come in we'll have some better tariffs. My parents house in Australia has a smart meter where the E7 rate applies each night and all weekend which is fantastic if you are out at work all day from Monday to Friday and don't need air conditioning or heating. On really hot days (or other days of very high demand) they charge more for use in a few early evening peak hours to discourage people from turning the air con to max. You can also choose a standard 24/7 rate as well and switch between the two whenever you want.

Terrylw1

FAI wrote: »

For information for anyone else with all electric site and GSHP so looking at Economy 10...
I tried the number provided by John1. I was redirected to 0845 301 5921 = E.On Domestic new connection team.
I spoke to a really helpful representative and here is what I learned.
1. E.On does install Economy 10 3 phase meters.
2. E.On does have an Economy 10 tariff in RG area.
3. E.On will only take me onto the Economy 10 tariff if I
a) arrange for the new meter to have a new MPAN (meter registration number), as opposed to re-using my current meter's MPAN number which is currently assigned to npower and b) get E.On to do the installation.
4. The new meter may have 2 MPAN's.
5. If I were to ask for Economy 7 meter and tariff the above restrictions would not apply.

Next step for me is to speak to SSE with whom I have a contract to do the installation work.

They have misinformed you here I'm afraid.

The distributor who generates MPAN's will not create a new one and disconnected an old one because a supplier wants to follow the new connection process.

Eon would switch you using your single phase meter, then arrange the secondary MPAN and book in the meter change.

The only time you are involved in MPAN generation is prior to the supply itself is installed as you are talking to the distributor. After this point, your current supplier always takes over.

I've narrowed down some meters for you on E10 last night but ran out of time to finish it until tonight. Do you want me to change that to a 3 phase E7 search instead?

You only need one MPAN for E7 and there are various types of E7. There are some known as split differential which have a 2+5 structure that kick in around 10pm ish and back again around 2am ish. I would have to check if these are in your region, if not, its the usual overnight types.

There are also E8's in your region.

Let me know because your existing problem of domestic 3 phase is still potentially an issue. From last night, some meters are defined as single or 3 phase but some are generic and don't state phases. So, I could check which E7's are 3 phase or generic and then you will know which you can use.

Terrylw1

Just to confirm on Malc's point on calling the Meter Operator.

These guys are just call centre agents that take calls from suppliers so they may not automatically know, but can find out. They may need to speak to a 3 phase or business team on their side.

Consumers are not allowed to call Meter Operators though in the Non Half Hourly market as their contract is with the supplier, not the consumer. So, they may refuse to help and can even report the instance to their contract management team to remind the supplier that they should make the enquiry on their behalf.

In terms of the meter, as long as you are going for 3 phase whole current, its just a standard meter connection. If you are going for CT metering, there is more to do but I doubt you are wanting this much power.

The main problem with 3 phase on domestic is that its very unusual. 3 phase is for business so the metering data isn't always available even if the meter is. To engineers on here, this may not seem like a big deal since they can fit the meter and it works, right? Wrong, if the industry data sees the meter as non domestic, you can look forward to future problems with every switch as you shouldn't have this type of meter. In reality, some customers need them (disabled customers with lifts or ramps for instance) but the industry data is often lacking. So, if I check this, I can tell you if its a problem and give you the industry data view...then the Meter Operator matches that to an available piece of kit for you (the industry data is loaded onto the meter).

FAI

Terrylw1 wrote: »

Just to confirm on Malc's point on calling the Meter Operator.

These guys are just call centre agents that take calls from suppliers so they may not automatically know, but can find out. They may need to speak to a 3 phase or business team on their side.

Consumers are not allowed to call Meter Operators though in the Non Half Hourly market as their contract is with the supplier, not the consumer. So, they may refuse to help and can even report the instance to their contract management team to remind the supplier that they should make the enquiry on their behalf.

In terms of the meter, as long as you are going for 3 phase whole current, its just a standard meter connection. If you are going for CT metering, there is more to do but I doubt you are wanting this much power.

The main problem with 3 phase on domestic is that its very unusual. 3 phase is for business so the metering data isn't always available even if the meter is. To engineers on here, this may not seem like a big deal since they can fit the meter and it works, right? Wrong, if the industry data sees the meter as non domestic, you can look forward to future problems with every switch as you shouldn't have this type of meter. In reality, some customers need them (disabled customers with lifts or ramps for instance) but the industry data is often lacking. So, if I check this, I can tell you if its a problem and give you the industry data view...then the Meter Operator matches that to an available piece of kit for you (the industry data is loaded onto the meter).

Thank you for making time to explain the potential issues with 3 phase meters.
I spoke to a manager at Scottish Power yesterday. He stated that I must keep the same (current meter) MPAN. We had already decided that we will not run 2 meters in parallel, but that we will supply power to the temporary log cabin in which we are living from the new meter when it is installed.
Yes I would appreciate any information you can give me so that I can get the 3 phase meter installed without it being "labelled" commercial; and yes it will be E7.
What data do I need to determine whether CT metering is needed?
3 phase current requirements are GSHP 22A running (41A start), 2 x 7.5amp immersion and Heatstar unti 13A per phase.

While typing this I have received an email from SSE saying that they will lay the 3 phase spur to the property, are arranging a new MPAN and that I have to organise getting the meter installed as they no longer do this part of the job.

ADDED LATER:
Today's call to Scottish tells me they are OK with a new MPAN, and that they use SSE for meter installs in my area, so it will just be a different SSE depot (not the Reading depot) doing the work

FAI

Terrylw1 wrote: »

So, I could check which E7's are 3 phase or generic and then you will know which you can use.

Hi Terrylw1, I hope you will be able to help me with the right phase 3 E7 meter.....:)

FAI

UPDATE: E10 tariff from E.On

I received a call from E.On from someone who new about E10.

I eventually was provided with the single E10 tariff that E.On supports.

I used this to cross check whether there was any saving versus the E7 version of my tariff with Scottish (Fixed Price to Nov 2014).

At 40% overnight usage and 10,000kwh p.a. I would save £12p.a., and at 50% £29.

So currently E.On's E10 rate is better than EDF, and it is available for 3 phase.

I will still be going for E7 with Scottish, mostly because I want to have a wide choice of tariffs in the future and a saving of £29 p.a. is not enough incentive to tie myself to E.On.

HappyMJ

Would you really be using so much overnight? I didn't think that a heat pump stored heat and instead gave you instant heat in which you would have the pump running during the daytime hours and turned off overnight (or set to the frost setting)....and besides aren't they a little more efficient when the temperature outside is a bit warmer such as during the day as opposed to the night? Granted that ground temperature doesn't change much though.

FAI

HappyMJ wrote: »

Would you really be using so much overnight? I didn't think that a heat pump stored heat and instead gave you instant heat in which you would have the pump running during the daytime hours and turned off overnight (or set to the frost setting)....and besides aren't they a little more efficient when the temperature outside is a bit warmer such as during the day as opposed to the night? Granted that ground temperature doesn't change much though.

Hello HappyMJ,

In all honesty, I do not know what % we will consume overnight. That is why I like Scottish E7 as the break even % with the non E7 version of the same tariff is at approx 12% overnight usage and any increase on that is a saving.

Our collector pipes are between 1.5 and 4.5 metres down and the ground temperature will not change significantly overnight. The warmth is supposed to also be provided by water in the soil aswell as the differential with air. The GSHP return feed warms an 800litre buffer tank to 35 deg C to subsequently circulate through the UFH, and the intention is to ensure that this buffer tank is up to temperature by the end of the night. After that, yes we will have usage in the day; and our ground is south facing so that will help.

Once the GSHP has been commissioned, we will be tuning the running of it to get the highest COP (coefficient of performance) i.e. availble heat in kW from running the pump, aswell as the lowest energy bill. It is definitely trial and error, but based on some good heat calcs for the total building....