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Discussion Starter #1
Dear Forum;

My first post here, hello!, I haven't an EV but thinking about getting on board.

One question I have is about home fast charging, based on my expected usage I have been put off by the lengthy time to charge a vehicle at home and would like to have a 12 or 22KW DC system installed....however I then imagine this might blow the fuse to my entire house...? (I am in a typical house with a single phase feed).

Has anyone else been through this process or have any recommendations? I imagine I will need to pay my utility to install a higher power line in.....which then starts to sound a tad expensive.

many thanks in advance

-JJ
 

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For charging over 7kW, 3phase is needed - the expense depends on the local area - you may have suitable cabling passing the house so just needs a trench and meter. Not a cheap option and will require a car with 2 or 3 phase AC charging. the actual wallboxes for 3phase AC do not carry a large markup.
Rapid chargers (DC chargers) are very expensive and not generally suitable for home use. Though if you have the land and a suitable feed it might be possible to set up as a rapid charge point.for the public.

If you are looking at DC charging then get a tesla MS it will be cheaper and with a suitable referal comes with free supercharging.
 

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Hi, JJ. Unless your usage is pretty unusual you should be able to make do with a 7kW charger. Bear in mind that you don't normally need to charge from "empty" every night - you just have to top up what you used each day. If you drive 50 miles on a typical day, you'll likely only use about 13kWh. So you can recharge that in a couple of hours.

If you are particularly unusual and drive 150 miles a day, if you have an EV that can support that, you'd still be able to charge overnight.
 

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One question I have is about home fast charging, based on my expected usage I have been put off by the lengthy time to charge a vehicle at home and would like to have a 12 or 22KW DC system installed....however I then imagine this might blow the fuse to my entire house...? (I am in a typical house with a single phase feed)
Welcome. Almost all home charging is installed at a maximum of 32 amps AC output for two very good reasons. As you say, the main limitation is the house supply itself. But also, most cars using AC input at home are fitted with a 7kWh AC to DC converter which limits charge speed whatever wall socket is plugged into.

To provide 3 phase power can be very expensive due to road and trench works - and not all EVs can accept that power anyway. And to install a Rapid charger from such a 3 phase power supply, so that 50 amp DC can be used, is prohibitively expensive for home use. Minimum £20k up to £50k.

You mention your 'expected usage'. If you expect to need more than a full battery for your daily use, and planned to return home to fill rapidly again, then you could have a problem. Such a pattern is rare though. Cab drivers have an intensive daily need and have a similar problem but they still cope by using commercial Rapids as they go about their daily travels. Many are also able to gain sufficient power in normal breaks for lunch and coffee stops using 7kWh posts. Frankly, if you need to Rapid charge at home every day, in addition to an overnight charge, then you might need to re-think about an EV being ideal for your needs.

Most people find that an overnight charge is sufficient to fill most batteries but regarding that as a 'lengthy time' is a red herring as you are asleep most of that time. And even a home charger can load 25 miles per hour so that a lunch hour and two stops gives an extra 50 miles over the normal range. If more than that is needed then a nearby Rapid visit for lunch would re-charge fully.
 

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Discussion Starter #6
Thanks everyone for the quick responses;

I will be sharing the car with my family and I also work odd hours incl shift work, so the car would not be guranteed to be home for many hours in a row, thus the interest in faster charging. There are also not many rapids (to my knowledge) near me.

It seems might need to have a new line into the home, either 3 phase or a beefed up 1 phase connection? Would a utility do this for free, since we will be using more energy, or something we might pay for. How much might this be, is this the 20K - 50K figure quoted above (which would be a definite deal breaker for us, I would like to drive electric, but not break the bank).

I have come across this unit..but think might be US only. Delta EV Wallbox Level 3 DC Quick Charger Charging Station

many thanks

-JJ
 

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Some ev's are 3 phase ac like the Zoe. These changes at rapids rates on ac so cutting out a big expense, call your electricity supplier about 3 phase before anything else.
Would it be cheaper to have 2 cars?
 

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It seems might need to have a new line into the home, either 3 phase or a beefed up 1 phase connection?
In the UK, you must have 3-phase to charge over 7kW on AC. It is possible to hack some cars to charge over 7kW on single phase, but they aren't sold that way. The original Tesla Roadster was the exception, but they haven't been made in years.

You also need a 3-phase capable EV.

Renault Zoe can charge at 22kW. Tesla Model S and X are either 11kW or 22kW. The 94aH BMW i3 can charge at 11kW. Mercedes B Class EV had 11kW 3-phase AC but no rapid charging.

Jaguar iPace might be 3-phase. Not sure. The upcoming LEAF 60 will probably have 3-phase, possibly as an option. The Tesla Model 3 will probably have 3-phase.
 

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Hi Folks

48A Level 2 EVSE HCS-60 Hardwired | ClipperCreek

Any thoughts on this? I know it has a J1772 connector but with a suitable adaptor why could this not be connected to a suitable single phase power supply in the UK? I'm thinking of this in terms of cars that have an 11kW inverter on board. (48 amps gives 11kW @ 230v )
Unfortunately that won’t work EVSE is really just a switch and controller the car determines the rate - no cars sold in the UK go above 32a single phase (with the exception of some modifiable vehicles mentioned above)
 

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Unfortunately that won’t work EVSE is really just a switch and controller the car determines the rate - no cars sold in the UK go above 32a single phase (with the exception of some modifiable vehicles mentioned above)
Hi Jack,
Thanks for your reply. The Leaf + is supposed to have an 11kw charger on board. So it the case it will charge at this rate only if the AC power source is 3 phase? And only at 7kWh if single phase?
 

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Hi Jack,
Thanks for your reply. The Leaf + is supposed to have an 11kw charger on board. So it the case it will charge at this rate only if the AC power source is 3 phase? And only at 7kWh if single phase?
Yes, or Nissan pull the trick they did with the ENV200 say it has 22kW charging suggesting 3phase AC but really you have to buy an additional baby CHAdeMO unit
 

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Hi Folks

48A Level 2 EVSE HCS-60 Hardwired | ClipperCreek

Any thoughts on this? I know it has a J1772 connector but with a suitable adaptor why could this not be connected to a suitable single phase power supply in the UK? I'm thinking of this in terms of cars that have an 11kW inverter on board. (48 amps gives 11kW @ 230v )

THat's really for the US market. Even if you had a spare 48A, 11kW cars sold here probably aren't wired to jump all three chargers to a single pin that is rated for 48A.
 

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Interestingly the cost of a new 3 phase supply is about 10% more than a new single phase one....I was quoted a ludicrous £6k+ for a single phase one and it's only a smidge under £7k for a 3 phase.

I didn't expect the single phase connection to be so stupidly expensive.
 

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An approach that includes some workplace charging can make a huge difference to the duration of home charging.

Another approach is to purchase an EV which has a high DC charge rate, one much greater than 50kW and lobby a network such as INSTAVOLT to get a 100kW rapid installed near you.
 

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Interestingly the cost of a new 3 phase supply is about 10% more than a new single phase one....I was quoted a ludicrous £6k+ for a single phase one and it's only a smidge under £7k for a 3 phase.

I didn't expect the single phase connection to be so stupidly expensive.
The actual costs of hardware aren't much different between 1 and 3 phase - one extra conductor in the cable, a 3-phase meter and a couple of extra main fuses. The bulk of the costs will be the labour - trenching, connections, testing, backfilling, and repairing the road (and dealing with the council) - which are mostly the same either way.
If a significant part of the cable run is on your property you might get the price down a bit by digging the trench yourself.
 
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