Electric car charging

DrEskimo

Slow would be 3.6kW from a 3pin plug. This is too slow for most large capacity. A 7kW type 2 would be ideal, which is what most home EV chargers are rated at, but this can be handled on a single phase 32amp.

Three phase would be 11kW or 22kW. The iPace can't accept anything higher than 7kW AC, so wouldnt be much use....as I said, the Zoe can and I think the Audi E-tron can be optioned with 11kW, but not sure about others.

MX5huggy

From what I understand the introduction of the 18th edition of the Wiring regs has added some extra complexity and cost.

gzoom

We have a 3 phase supply in our current house. Would in theory allow our Tesla to charge as 18KW rather than 7KW. But the cost involved to get a 3 phase meter put in, additional wiring etc isnt worth it for us.

To the OP, depending on the state/age of your current electrics there might be a decent amount of prep work to be done. Its not something to rush/cut corners on.

Your looking at a constant 7KW drain over a constant 8hr+ period, and potentially daily for as long as you own the house. Just look at the headlines or tumble dryer fires to see why its important every bit of detail is checked.

We've had three 7KW points fitted over various property over the years, and regulations are constantly changing. Currently looking into getting a 7KW point fitted to a Victorian era end terrace in London with electrics that hasn't been updated for a long while, so ought to be fun. Also now looking to get a second charger fitted to existing property, which might push us to get a 3 phase meter put in.

Jackmydad

3 phase generally makes an installation much more expensive. The switchgear and distribution gear tend to be more "industrial" so more expensive, and everything is bigger and "3 off"
What is going to be a problem at some time with car charging, is supply capacity at local level. (To say nothing of national level!)
30 years ago we wanted to put off peak heating into a cottage near here, and SWEB were very iffy about the capacity of the local sub station then. I don't think it's been upgraded since. I suspect the feeder to it is limited in capacity.

Angus_Og

What an interesting thread.

Just bought a new car and toyed (briefly) with electric but it sounds a nightmare.

So can someone explain the options and costs for setting up for home from scratch from basic to best assuming you don't have a 3 phase.

Interestingly was talking to my mechanic the other day and he was saying there are two charging points near him and it is the same two cars that gog the charging points.

System

knightstyle wrote: »

Tarambor with 3 phase the UK now has 400v between phases, not 450v.

Thanks for the correction guys. I remembered it was over 400V, for some reason 450V came to mind. 415 sounded more familiar once someone mentioned it.

Robin9

Jackmydad wrote: »

3 phase generally makes an installation much more expensive. The switchgear and distribution gear tend to be more "industrial" so more expensive, and everything is bigger and "3 off"
What is going to be a problem at some time with car charging, is supply capacity at local level. (To say nothing of national level!)
30 years ago we wanted to put off peak heating into a cottage near here, and SWEB were very iffy about the capacity of the local sub station then. I don't think it's been upgraded since. I suspect the feeder to it is limited in capacity.

I was Distribution Company design engineers many years ago and we talked in terms of After Diversity Maximum Demand - this said that although you had many appliances you only used a few at a time; your neighbours had the same but used them at different times; some neighbours would be on holiday; some houses empty etc. Typically when gas was used for heating we designed our underground cables to 1.6kw to ensure every one had a statutory voltage.

I see an issue of old estates with lots of electric cars with say 7kw charging points all being used at night creating problems for the distribution companies.

Jackmydad

Robin9 wrote: »

I was Distribution Company design engineers many years ago and we talked in terms of After Diversity Maximum Demand - this said that although you had many appliances you only used a few at a time; your neighbours had the same but used them at different times; some neighbours would be on holiday; some houses empty etc. Typically when gas was used for heating we designed our underground cables to 1.6kw to ensure every one had a statutory voltage.

I see an issue of old estates with lots of electric cars with say 7kw charging points all being used at night creating problems for the distribution companies.

I understand diversity, but it only stretches so far as you say in your final comment. This is a rural area, and it has to be quite a long feeder to the sub station apart from anything else. They were quite concerned 30 years ago about the load. (I must say I was surprised as it was off-peak and I doubt if that many homes around here have that)
Part of the problem with charging loads, and for that matter storage heating loads is that they are more or less continuous.
It's an interesting problem for someone. . .

AdrianC

Robin9 wrote: »

I see an issue of old estates with lots of electric cars with say 7kw charging points all being used at night creating problems for the distribution companies.

A few years ago, Western Power replaced the transformer for our little throng of 7 rural houses and one small working farm. The one that came out was the original that had been installed in the 60s, when AC came into the area...


The replacement was the same 200A rating. All three 11kV conductors run across fields to it, but it's single-phase, only connected to two of them, so we simply won't ever have three-phase available without covering the cost ourselves of replacing the transformer again.

I was surprised at the time about the lack of future-proofing, and asked the WP guys... "Yeh, you're absolutely right. We'd love to upgrade - but the supply network is all a bit borderline as it is, and we aren't risking increasing the load on it, because it could all go down."

Jackmydad

AdrianC wrote: »

A few years ago, Western Power replaced the transformer for our little throng of 7 rural houses and one small working farm. The one that came out was the original that had been installed in the 60s, when AC came into the area...


The replacement was the same 200A rating. All three 11kV conductors run across fields to it, but it's single-phase, only connected to two of them, so we simply won't ever have three-phase available without covering the cost ourselves of replacing the transformer again.

I was surprised at the time about the lack of future-proofing, and asked the WP guys... "Yeh, you're absolutely right. We'd love to upgrade - but the supply network is all a bit borderline as it is, and we aren't risking increasing the load on it, because it could all go down."

That's the real problem. The whole system was given a heavy diversity factor when installed in the days when the biggest single (domestic) load was probably a cooker.

Probably easier to upgrade in areas where there was a lot of industry as the feeders and so on will be heavier, but upgrading rural areas would (will?) be a massive undertaking.

And then of course you need the generating capacity.