Phase 3 electric Suppliers Domestic vs Business

DoodleDay

We recently had 3 phase installed at our home, while we were having building work done. Reason mainly 'future-proofing' re electric car charging & partner wants to do welding etc. Plus the 3 phase wire was on a pole was in our garden so helped minimise the cost! 

The problem I have is getting comparative quotes from suppliers. I have discovered many domestic suppliers don't do 3 phase, so the normal comparison sites won't work for us & I can't access3 phase comparison business sites without changing our MPAN to business rather than domestic (which we could do as we have a smallholding & I am self employed working from home).
We currently use around 6000kw/year (approx 25% on cheap rate), which is obviously going to be a very small amount on a business account. Currently with EON but contract has finished so now is the time I would normally be shopping around to get best rates.

Will the rates & tariffs still be competitive if we change to a business, or should I stick to being domestic & just allow several hours & much patience trying to access a human at Eon, OVO Octopus & Scottish Power to get quotes? (They are the only ones I have found out so far that do 3 phase domestic)
One electric business broker I managed to speak to on the phone said, 18 months ago it was probably worth switching to business but not so sure now.

Thanks in advance for any advice - & direct tel numbers or emails for domestic 3 phase providers!

QrizB

Business tariffs were at one time cheaper than domestic, but the downside was that they don't get the same protections from Ofgem or through general consumer law. We had a lot of anguished posts on the forum in 2022 when they were stuck with business tariffs over £1/kWh.

I'd suggest you weigh up the pros and cons very carefully. When speaking to your broker, for example, bear in mind that you won't get a cooling off period - if you agree to a contract, you're stuck with it.

I'm pretty sure all the major suppliers will offer domestic contracts to 3-phase customers, but you might have to do your comparisons yourself (the old-fashioned way).

Robin9

QrizB said:

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I'm pretty sure all the major suppliers will offer domestic contracts to 3-phase customers, but you might have to do your comparisons yourself (the old-fashioned way).

Agree -  ring around .

tamste

As you are domestic, is the three phase supply with 415v to all sockets, or is it split into 3x 240v circuits?

I have a 3 phase supply as heavy user with storage heaters, and its a 415v feed split into 3 x 240v circuits (L1, L2, L3). If yours is the same setup, then can't see why you need to have a commercial contract. 

Robin9

@tamste

Agree -  3 ph supplies with your set up are not uncommon.  

Who is your supplier?

Scot_39

tamste said:

As you are domestic, is the three phase supply with 415v to all sockets, or is it split into 3x 240v circuits?

I have a 3 phase supply as heavy user with storage heaters, and its a 415v feed split into 3 x 240v circuits (L1, L2, L3). If yours is the same setup, then can't see why you need to have a commercial contract. 

415V in final stage in UK is generally if connecting phase to phase - based on same normal final stage 240V nominal 1 phase to neutral - prior to harmonising voltage with Europe's lower nominal standard 230V.

Which these days should arguably be described as 230V * 1.73 = 400V nominal for 3 phase supply.

The European 220V and UK 240V nominals merged nominally to 230V - late 80s iirc.

However in reality the upper range contains the UK standard 240V - so no real change required.

Where live phase line to live phase line (e.g. A to B etc ) is 1.73x (sq root 3) line to neutral (A to N etc) voltage.

Nearly everything domestic will be run phase to neutral at 230V / 240V.  

So one half of a larger house - might run off a different phase to another - or something like a BEV charger or ASHP will come from one phase to neutral, whilst lights and sockets etc another.

QrizB

Scot_39 said:

So one half of a larger house - might run off a different phase to another - or something like a BEV charger or ASHP will come from one phase to neutral, whilst lights and sockets etc another.

While agreeing with everything else, note that the larger sizes of ASHP (and GSHP) call for all three phases.

tamste

My setup is 3 phase supply in, L1 for general plugs and lighting with L2 and L3 used for the storage heaters, all phases operating on 230/240V.

Was just making the point that as the property is domestic, you shouldn't need to go on a business contract for your supply. There are a few of us out there with a domestic 3 phase supply on standard domestic contracts.

3 phase comes in handy if you want to have solar as well as you can have a 10 kWh (actually max 11.04 kWh, but lets not quibble) on a G98 application, i.e. do and tell as its 3.68kWh per phase, so with 3 phases you can export 11.04 kWh.  11.44kWh (26 panels) is what I have but its controlled to no more that 10 kWh by the inverter, and I don't expect to actually get the 11.44 kWh due to losses. Works for me .. this time of year is expensive, but the SEG payment through the summer makes the system worthwhile.

QrizB

The Unit Police will be along shortly to remind you of the difference between kilowatts and kilowatt-hours

Gerry1

                

Scot_39

QrizB said:

Scot_39 said:

So one half of a larger house - might run off a different phase to another - or something like a BEV charger or ASHP will come from one phase to neutral, whilst lights and sockets etc another.

While agreeing with everything else, note that the larger sizes of ASHP (and GSHP) call for all three phases.

Thanks - will maybe have a look at the upper power ranges for domestic models.

I think I've seen BEV chargers use multi phase as well - but that was giving upto over 20kW - way over the standard around iirc 7kW rating most fit domestically.