3 Phase *Running* Costs Question

happyplants

All, I can't get answers anywhere on this and EI won't answer the phone within 40 minutes etc, so hoped someone may know.

We are looking at a renovation to include heat pump and already have existing EV charger. Solar is coming in and we have space and ability to go relatively large.

The M&E consultant noted we had 3 phase supply to the house, but not in use and is recommending this. Some of it seems to do with the 11kwh inverter possibility and feedback at that level to offset costs. I have not run all the data yet on whether it makes sense.

I understand all the install costs, but I can't get anywhere in understanding whether the electricity is supplied at the same or different rates or whether a three phase supply is treated as de facto commercial. Leaving aside simply unit costs (which I am interested in) does a three phase supply commit you to some sort of supply that isn't as "easy" to switch when prices change?

In essence, we have the option to have the house on three phase, I'm being told its a good idea from a M&E point of view, but I'm more concerned about running costs and operational constraints (i.e. can you have a day / night rate) which no-one seems to have information on.

Any insight would be great.

antoinolachtnai

The answer is broadly no, no extra charges. Your charges depend on your distribution group and load profile (top right of your bill) not the number of phases.

I would get an electrician to check that you have a 3-phase meter. It could be there are three phases to your home but they are not connected to the meter. If this is the situation you want three phase you will have to get ESBn to do an upgrade.

You should get your supplier to confirm this to your satisfaction.

kirk.

Post pictures of the ESB setup

He could be mistaken on the 3-phase supply being there , hard to say

happyplants

https://www.boards.ie/discussion/comment/120040487#Comment_120040487

Thanks, I understand most of that and we are confirmed both on three phase availability and works costs.

I'm not concerned with those charges, but with the basic unit rates and the way in which they are offered. In a basic sense, can I still avail of whatever home packages are offered etc and whether anyone has experience of this. This is what I can't get any answers on.

What I can't get answers on is whether, say, all the standard Electric Ireland packages apply that I can chose from in a domestic setting, ditto for all other companies or whether by doing this I end up committing to some "commercial" style system / costs package that has a different tariff or different way of billing.

happyplants

https://www.boards.ie/discussion/comment/120040771#Comment_120040771

No, no. No mistake. Its not about that at all.

I'm not concerned with any installation / works costs, so you can assume that if any upgrade needed it will be done is being done. There's no problem getting all costs on that, and I have them.

The issue is just with the running costs - i.e. does it change anything about unit rates etc, what plans are available and so on or whether I am lumped into "commercial" or "business" as a result.

antoinolachtnai

https://www.boards.ie/discussion/comment/120040784#Comment_120040784

The answer is that as long as you stay DG1 then you will continue to have access to the same offers that other domestic customers avail of. You need to check this with your supplier.

If you already have 3 phase, then absolutely nothing changes.

kirk.

https://www.boards.ie/discussion/comment/120040786#Comment_120040786

You'll be a domestic customer I presume

Afaik the day/nite is available for 3-phase if they're still fitting it now.

Afaik the 3P smart meters are on the way.

happyplants

https://www.boards.ie/discussion/comment/120040808#Comment_120040808

Thanks, yes, as long as I stay a domestic user (whether DG1 or 2) I would assume domestic user rates would apply. My concern is staying a domestic user with this up and running. Contacting suppliers is the problem as they can't answer whether by reason of call centre approach or whatever.

I'm perhaps not being clear here. Thanks for your time. What I was hoping to find was someone, on a residential 3 phase connection who could confirm that they still have the same tariff access as before without additional layers of annoyance when trying to deal with it.

kirk.

It's unusual to have a 3-phase supply not in use unless it was changed back to SP metering at some point , hence why I asked

The likes of a looped single phase service might appear to be 3P to the consultant

antoinolachtnai

is there a three phase meter I wonder?

kirk.

Doesn't seem so from the op ?

Difficult to know if he's saying the supply is outside the house or at the meter location

A 3 phase domestic supply isn't that unusual ime , but for it to not to be in use is more unusual

Says he has the costs anyhow so must be available

antoinolachtnai

So maybe OP is talking about upgrading the supply to three phase, not that they have three phase at the moment.

kirk.

Probably

If it was a spark doing the surveying I wouldn't query it

Some of these "Engineers" are clueless on electrics

happyplants

https://www.boards.ie/discussion/comment/120044473#Comment_120044473

Sorry, I was away from this. Its a long story, but there is three phase availability at very little cost. The relevant "stuff" has all been built on the lands. There are specific pieces of electricity infrastructure which I've been told are the 3 phase "things". The house some considerable distance from the roads and the point really is that all this work has been done, so there is very little left to do. I don't know why the prior owner didn't complete it, having done and paid so much, but they didn't. I suspect they intended to operate a workshop, but then business tanked or something like that. In any event, the supply as far as I can tell has been brought about 700m off the road, up to about 5m from the house with two poles standing up with a very specific looking device on the poles which is what everyone looks at when they come here and then asks "do you have 3 phase here?

However, I just wanted to know if we obtain a 3 phase connection, is there a change in the range of rates / tariff's available or whether I'd be fighting with retailers trying to put me on commercial rates etc.

antoinolachtnai

The answer is still the same as before I think.

ECO_Mental

https://www.boards.ie/discussion/comment/120143090#Comment_120143090

I don't know if there are domestic 3P rates but it will all depend also on the MIC you want. If you get an MIC over 29 kVA you will be going into max demand tariffs where they will be logging your demand every hour and if you go over importing your MIC at any time you will be charged penalties, also if you go over 29 kVA MIC you will get an MIC charge for every 1 kVA you have, so that's an extra charge every month.

The rates might be cheaper but there are other costs...

antoinolachtnai

if OP stays DG1 (domestic) there are no maximum demand tariffs or any of that. If OP goes to a commercial distribution group then commercial tariffs and kVA charges and MD is an issue ( DG6 is maximum demand /kVA charges ). Domestic is always 29kVA or less at least nominally.

Main thing is to make sure ESBN are aware it’s completely domestic and that connection offer letter says DG1.

happyplants

https://www.boards.ie/discussion/comment/120155390#Comment_120155390

Thank you, this is precisely the kind of things I wanted to know.

And separately thanks to the following poster. The lesson is to police strongly the domestic nature of it (which it is) - its really just about making sure new showers run with a relatively big heat pump and two EV's charging as well as charging a few other vehicles I use for the landscaping etc.

ELM327

https://www.boards.ie/discussion/comment/120160567#Comment_120160567

And balancing the phases for those heavy consumers too