Tariff and/or Metering Options for Two Phase Supply

Qyburn

I might not have to deal with this myself, but I'm wondering what options are available nowadays for a two phase supply. The context is a former local authority building, which is to be taken over by an organisation I'm involved with. At that point we'll be responsible for the electricity supply.

It's a two phase supply presented by the DNO as a three phase service head with only two fuses. Each phase is currently has a separate meter. All loads are single phase, there's no two phase machinery.

Anyone dealt with a similar situation?

QrizB

Just checking this is a commercial property, not a residential one?

squirrelpie

All loads are single phase, there's two phase machinery.

Just checking there's a 'no' omitted in the second half of that sentence?

Qyburn

Thanks. It's correct it's a former school, not residential. And yes I did mean "no two phase machinery"

Netexporter

As you usage pattern is probably very different to the LA use, you might want to look into eliminating/combining various circuits and consolidate into a single phase supply. This is assuming the 2-phase has a higher standing charge.

However, looking forward, you may wish to use a heat pump, for which there may be grants available. It would likely require a three phase machine for what sounds like a substantial building, so you might be better off leaving it as it is, until you require a 3-phase upgrade.

Scot_39

Not really my area of expertise but was curious

Before your post made it clear you were looking at commercial (school) rather than domestic - I was wondering about 2 phase and domestic.

The closest I could think of was 2 cables to 2 meters as per an old bosses barn / home conversion.

Then I remembered the doc NG put out on the 100A to 80A fuse limits.

I cannot find the original NG release anymore (the link to the commercial.nat….. fails now) but this transcript of another DNOs - NPG take on it seems fairly close to as I remember it (apart from I think NG preference is 3x60A domestic and 3x80A is more their special case upper limit or is their commercial limit)

https://www.speakev.com/threads/northern-power-grid-no-more-100a-fuses-and-re-actively-downgrading-to-80a.184694/

And it appears there was a light commercial 2 phase option - or more accurately 2 options in one respect - phasing. As given in the new high load option section of that "no more 100A fuse" list of possible grid connections - their was something I didnt pay much attention to before - the split phase at 80A option.

And a quick google led me to this NG document. Which I then did a quick search of that term - and this led me to Section 3.3 - which covers two different twin phase scenarios - one of which could well be relevant to you (given the scope is domestic and light commercial)

https://commercial.nationalgrid.co.uk/downloads-view-reciteme/652670

But its all a little over my head these days.

Given twin meters - its potentialky just treatablecas two independent mpans - which domestically can be from 1 phase incoming - for things like old twin meter e7 and more complex multirate tariffs / circuits onnold rts. rts. Some still get dual mpans for their twin element rts replacements. But commercial energy contracts are different - with a lot less protections and again never had one.

QrizB

We've seen occasional threads on this forum where people have had dual-MPAN supplies using two separate legs if a three-phase DNO cutout and two separate meters.

This sounds similar to the situation in the OP.

pete-20-11

Could it be swapped to a three phase meter to save on the standing charges?

Qyburn

Thanks. We don't think the supply itself can be upgraded to three phase, or not without major expense. But I have wondered whether a three phase meter can be installed with only two phases actually in use.

Electrical loads are a consideration. At the moment heating is by low level tube heaters, direct electrical heat, the most expensive sort. Realistically we won't be able to change that in time for this Winter, but we will possibly go for air/air heat pump in due course.

gm0

Edge case for modern smart metering. In the pre half hourly world for industrial/commercial. We used to make 1,2,4,8 register setups but that more or less died out with the introduction of half hourly wholesale and it moving down the industrial sizes towards the consumer.

Depending on intended connection and use via refurb of the building. Dual domestic MPAN (dual standing charge) 2x singe phase and standard smart meters would of course work. A low standing charge tariff on the "lesser" used leg could make this less prohibitive than it otherwise would be. But doubling up undesirable.

Assuming there is currently a "single supply" on national database (and billing). Then your debate with suppliers needs to be framed as such. I'd like to be supplied by you - please fit an appropriate new smart meter to this single supply. Knocking back attempts to claim it's two supplies.

In your shoes I would go to a larger supplier - one who has some skill in the diversity of metering hidden behind customer services for "legacy" sites. Small new entrants may not have encountered / won't know what to do with you and the simplest option for them is to try not to sign you up. Rather than sort it out with meter operators/dno/national db etc.

Remember though a 3-phase meter is also a bit niche and can be tariff restrictive in a consumer setting. You can get it but not whole of market or all choices.

Modern billing engines especially for consumer and new entrant are not always brilliant with odd corner exceptions.

On the other hand. Having an established 2nd 80 or 100A is useful. Car chargers. Heat pumps etc. Solar export. I would try not to decommission it but rather find a way to keep it cheaply.