22kW charger, because why not?

[Durzel]

Looking at getting a home charger installed for current and future EVs, and it seems logical to go for a 22kW one for future proofing.

All I know about this is that it will require 3 phase. The property is currently serviced by nPower and just has a regular supply (more than one CU for what it's worth, there are several outbuildings). Do I just phone them and say "give us some 3 phase mate please thanks" and deal with the guy/girl on the other end of the phone sucking air through their teeth, going "ohhhhh dear oh dear that's gonna cost ya" ?

Or do I phone a completely different electricity company? I don't currently have a smart meter and nPower have been utterly useless at getting one sorted for me, so I've given up.

Thanks in advance

[ruggedscotty]

It can be costly - all depends on if the DNO have already capacity to supply you, if not then you will have to pay part rota for an upgrade of their network to do this for you. Could be up to 10 grand if they need to upgrade their network and provide a new transformer etc. you can get a free quote from your network provider.

[anonymous-user]

It is your local district network operator you need to speak with. Mine, for instance, is northern powergrid

Interested to hear what the outcome is

[anonymous-user]

I'd be a bit careful as "powerful" 3 phase charging is really becoming obsolete and is being replaced by DC charging, mainly because that moves to an off-board rectifier and hence makes the car cheaper...

IME, a 7kW charger is really all you need unless you are doing 300 miles a day every day

[kambites]

Max_Torque said:

I'd be a bit careful as "powerful" 3 phase charging is really becoming obsolete and is being replaced by DC charging, mainly because that moves to an off-board rectifier and hence makes the car cheaper...

Surely the input to the more powerful DC chargers is three-phase though?

[Durzel]

Thanks all. I guess 7kW would be enough, just figured 22kW would be more future proofed, but I guess maybe not if the cost of getting 3 phase installed is several thousand.

[Flooble]

If you work it out, at 3 miles per kWh, overnight you can stuff in 7kW * 9 hours * 3 miles/kWh = 189 miles

Now, granted you may do more than 189 miles a day or you may not be home for 9 hours at time. But I'd say both of those are going to be pretty much an edge-case. You'd also be getting home pretty empty to have 63kWh of capacity in your battery, unless you're driving a top-end Tesla.

More likely is getting home at 1830 from your 150 mile commute and then having to take the kids out to after-school activities. Which is where you might be in trouble if your EV only has 200 miles of range to start with and you aren't home long enough to shovel any charge in.

[gangzoom]

Adding a new 3 phase supply to a existing single phase can easily cost 5 figures.

We already have a 3 phase supply running into our house but only a single phase meter, I was told to expect a near 4 figure bill if I wanted a 3 phase meter and getting all the necessary wiring changed etc.

There is very little benefit to 22KW charging at home, not unless you really need to add 100 miles of charge in a few hours. For most people plugin in at home and leaving it overnight to charge is all thats needed, there is no difference between charging finishing at 1am versus 7am.

Also bare in mind not many EVs sold these can charge at over 7KW. Current S/X can do 17KW, 3 11KW, eTron 11KW, iPace/Leaf/Kona 7KW.

The only EV that can actually do 22KW I think is the Zoe, or eTron/older S/X with 'dual chargers' optioned up.

Edited by gangzoom on Wednesday 8th May 21:13

[ruggedscotty]

Max_Torque said:

I'd be a bit careful as "powerful" 3 phase charging is really becoming obsolete and is being replaced by DC charging, mainly because that moves to an off-board rectifier and hence makes the car cheaper...

IME, a 7kW charger is really all you need unless you are doing 300 miles a day every day

and how do you get the power to your charger ? its actually the other way single phase is going out of fashion. they are looking at getting more houses 3ph capable, although that means 400v in houses which is a huge difference to 1ph 230v supplies.

three phase rectified to dc gives more power than a single phase rectified supply, 6 pulses compared to 2 over one cycle. off board rectifier makes cars more difficult as you need to ensure that you can find a charger that suits your car, chargers are not standardised yet but power supplies generally are, 230v 1ph or 400v 3ph. Better having a car with a rectifier charger on board as it makes the car more adaptable.

[granada203028]

I got a quote maybe 10 years ago for about £2K plus ground work, from South Western Power Distribution. A much bigger meter box would need to be fitted. House is 1996 vintage. 3 phase cable runs under the path in front of it. They said it could be connected live using some special technique so don't have to power the whole street down.

Present 1 phase is 100A fused so already 24KVA, so 22KW charging already possible with suitable conversion equipment if other loads minimised.

[Durzel]

Thanks all. Guess for the time being there's no need to go overboard. Will put in a speculative enquiry to the electricity board to see what sort of numbers I'd be looking at, but will look at getting a 7kW charger instead.

[syl]

granada203028 said:

Present 1 phase is 100A fused so already 24KVA, so 22KW charging already possible with suitable conversion equipment if other loads minimised.

This is the reason we should all have 3 phase. Try plugging 3 cars in overnight to charge whilst a couple of people want a shower, the oven gets used and everyone wants lights / TV / computers.

[SWoll]

syl said:

granada203028 said:

Present 1 phase is 100A fused so already 24KVA, so 22KW charging already possible with suitable conversion equipment if other loads minimised.

This is the reason we should all have 3 phase. Try plugging 3 cars in overnight to charge whilst a couple of people want a shower, the oven gets used and everyone wants lights / TV / computers.

I'd say most households will continue to have an 8-10 hour window overnight for car charging where there is very little else going on? That's certainly what I do anyway as cooking/showering etc. is usually finished up well before 10PM even in a household with 2 adults and 3 teenagers.

[granada203028]

SWoll said:

I'd say most households will continue to have an 8-10 hour window overnight for car charging where there is very little else going on? That's certainly what I do anyway as cooking/showering etc. is usually finished up well before 10PM even in a household with 2 adults and 3 teenagers.

That's right. My Leaf only needs 10KWh per night for the prospective trip to work in the morning, Where as the house could provide twenty times that, 20KW from 9 pm to 7 am.

Trouble is the further up the electricity supply infrastructure you go, the closer peak demand matches average demand so there will not be anything like that headroom for the whole street. So some sort of demand management would be required. So long periods of heavy individual demand are likely to be prohibited when it becomes common place.

Maybe it could work if everyone slow charges over night and a few can fast charge at random times as longs as there is no popular time and they don't clash.

[Mr. White]

ruggedscotty said:

It can be costly - all depends on if the DNO have already capacity to supply you, if not then you will have to pay part rota for an upgrade of their network to do this for you. Could be up to 10 grand if they need to upgrade their network and provide a new transformer etc. you can get a free quote from your network provider.

I was quoted £25k. They got a fairly short reply.

[syl]

SWoll said:

I'd say most households will continue to have an 8-10 hour window overnight for car charging where there is very little else going on? That's certainly what I do anyway as cooking/showering etc. is usually finished up well before 10PM even in a household with 2 adults and 3 teenagers.

There might be a long window, but many will come home at 6-7pm and plug their car in, which (I assume, I don't have an EV) will then proceed to charge itself at full speed. People will plug it in every night, "just in case". So even if only a small charge is required, between 7-10pm the demand will be high.

[gangzoom]

syl said:

There might be a long window, but many will come home at 6-7pm and plug their car in, which (I assume, I don't have an EV) will then proceed to charge itself at full speed. People will plug it in every night, "just in case". So even if only a small charge is required, between 7-10pm the demand will be high.

I get home at 6pm and plug in my EV straight away, but the car doesn't start charging till 1am when E7 rates kick in, and stop charging when it gets to 8am when E7 rates finish.

Its all controlled by software on the car/phone App.

If I really need more charge than what 7hrs can deliver I simply over ride the charging setup using the App.

[jjwilde]

3 phase inc the meter to my house cost £940.

If the capacity is there and you're close to the road it's pretty cheap.

This was with Northern.

You can make it cheaper if you're willing to dig the trench if it is needed (it was not needed in my case, they went over head).

It's ALWAYS worth getting a quote and I think a lot of people are put off by this 'it will be £10k' stuff.

[Mr. White]

jjwilde said:

3 phase inc the meter to my house cost £940.

Git.

(in the nicest possible way).

[Heres Johnny]

Its also worth noting that unless you go 22kw on three phase its not worth doing even if you can't use it all as 11kw is only 16a per phase and a car that can only charge from a single phase will be getting just 3.5kw. And I imagine getting DNO approval for 22kw is harder than getting it for 11kw.