3 phase loading for new supply

[kandgmitchell]

Hi,

We had got a budget quote for a new supply from Northern Power Neworks for our new build. Whilst talking to a very nice lady she mentioned that 3 phase would be available to the site for an extra £300. This seemed like a deal to future proof (it's an all electric house ASHP, EV charger PV etc.

Another very nice lady met me on site yesterday to agree the cable route and finalise the quote (which is of course more than the budget). She had a warning though they can only supply 30kVA at three phase - if we wanted the full 45kVA they would have to renew the existing cable probably back to Sizewell B or somewhere.

Now having just finished the structural design and working on all the other bits a new build needs I could do with a quick answer to "will this be a problem" as I could do with accepting this quote to get a connection to site for our impending static caravan to hook up to.

 

Thanks in advance

[Kelvin]

You’re not going to upgrade the cable obviously so it is what it is. 3 phase complicates the electrics a bit but for an extra £300 it’s worth doing. You are unlikely to use all that anyway. 

[PeterW]

Why would you want 45KVA..??!

 

30KVA is 135A on 3 phases - that’s pretty significant loading and even with an all electric house you’ll struggle to pull that unless you’re doing something vastly wrong !! 
 

With the right design you will struggle to pull 45A on a single phase even with the  hob/ovens/tumble dryer and all the lights on.. 

[kandgmitchell]

Thanks guys,

 

I presume she was just having to warn us about the lower figure. From what I'm getting is that we can agree the supply now and press on with the detailed services design, confident that there'll be enough juice to support any proposal put forward.