Interest only, electric car charging points 7 kW or 22 kW?

27 Jan 2008
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Llanfair Caereinion, Nr Welshpool
United Kingdom
Where I work we have two three phase 22 kW EV charging points, I had assumed that all cars that plug in can charge at 22 kW, however watching a U-tube video I see many cars can only use a single phase, so although the EV point can deliver 22 kW the car only charges at 7 kW.

This raises a number of points, including taking up a 22 kW charging bay for three times the time one should as only using ⅓ of the supply available.

Parking where I work at times is at a premium, to the point where I go to work on a push bike so to leave more spaces. We are seeing both charge points in use, considering we are running at reduced capacity due to Colvid restrictions once these are lifted we expect to see more visitors.

So some one using the charge bay for three times as long as they should, is likely going to cause problems. As will non customers using the charge bays. So how many electric cars can only charge at 7 kW?
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I can't answer your question, but it is certainly interesting. I suspect that any electric vehicle that supports "fast charge" will charge at 22 kW and a lot more, if the supply can provide it! Teslas fast charge at over 60kW. Even a humble Nissan Leaf (with the appropriate connector) will fast charge at 50kW:
It seems we have type 1, 2, and 3. And the type 2 upload_2022-1-6_12-36-11.png upload_2022-1-6_12-36-31.png is the one in question, the connector on the car
has 7 connectors with three phase versions, and two as seen here not populated with the single phase version. So some cars when plugged into a type 2 charging station get 22 kW others only 7 kW.

It all started after watching a U-tube video about using this upload_2022-1-6_12-50-32.png type of charger which simply plugs into a 32 amp socket, I did not realise they existed, variable charge rate 8 - 32 amp and since the charger is not fixed, all the safety features which an installer of an EV charger should consider, supply type, type of RCD etc. All go out the window, as the installer is only fitting a standard 32 amp socket, which could be used for a welder for example so not covered by the rules for EV charging points.

It also means a large saving, the charger retails at £270 the video
was an eye opener as I was unaware you could get a 7 kW plug in charger, I though only 2 kW versions were available.

However it was not that I started thread about the car it seems a Hyundai does have a rapid DC charging point, but for AC charging maximum charge rate is 7 kW. So although the charger where I work can charge some cars at 22 kW it seems others are still limited to 7 kW which as it stands is not a problem, but as electric cars on the road increase, we are likely to see people waiting their turn to charge cars when the car in front of them in the queue is only taking a ⅓ of charge available.
I suspect that any electric vehicle that supports "fast charge" will charge at 22 kW and a lot more, if the supply can provide it!
I looked at the link and note

So a 7 kW charger takes 6 hours and a 22 kW charger also takes 6 hours, so it seems it also only uses one of the phases available?
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For AC charging, the charger unit is in the vehicle - the 'charger' on the wall is just a box which switches the AC on and off, and has some other electronics to limit the rate of charging to some predefined values, plus various safety features.
Most vehicles have a single phase charger which is up to 7.2kW. Some have 3 phase which in theory is 22kW. Some vehicles may have charging devices which only support lower rates such as 6kW.

Most EVs use a Type 2 connector. A few older ones have the Type 1, which is electrically compatible with Type 2 so just needs a different cable - Type 1 at the car end, Type 2 on the other end.
For most, it's a cable with Type 2 on both ends.
For charging at home, the cable is normally tethered to the EVSE, as that's more convenient than removing and storing the cable each time.

If installing EVSE (what most people call a 'charger') then it's either a 7kW single phase if the location has single phase, or a 3 phase 22kW if the location has 3 phase.
Any car can plug into any outlet - if the car supports 2 or 3 phases and those are present, then they can be used. If not, only one phase is used.
A car with a single phase charger can be plugged into a 3 phase EVSE, but will only use a single phase and still only be 7kW maximum.
Charge rate also depends on the cable between the EVSE and the car, the state of charge of the car battery, temperature and other settings in the vehicle or EVSE which can limit the rate depending on external factors such as multiple units in a single location limited to a total power shared between them, or on the availability of local solar power, etc.

AC charging is intended to be used over a longer period at a low rate, typically when parked for several hours, or where the journey made to get there is relatively short, such as parking at a supermarket when shopping. Typical use cases are charging at home, when parked at work, when staying overnight at a hotel, at a gym, parked on the street, or anywhere else where the vehicle is likely to be parked for a few hours.
That's also why the nonsense about 'range' is mostly irrelevant - EVs are charged wherever they are parked regardless of how much range remains, rather than driving until nearly empty and then queuing up at Tescos on a Friday afternoon to refill.

DC charging uses the CCS connector, which is the same Type 2 connector with two extra connectors below it.
The large connectors are DC, and the smaller pins in the upper connector are used for communication between the vehicle and charger.
AC to DC conversion is done in the charger unit, which is why DC chargers are so large and expensive.
Charge rates go from 22kW upwards, and depend on the capabilities of the charger and what the vehicle can accept. Other factors such as battery charge level, local power availability and so on can all affect the actual charge rate obtained.
DC chargers always have a tethered cable.

DC charging is intended for situations where a large amount of energy is required in a short time, such as to add a couple of hundred miles when stopping at a motorway service station.

The only other variants are the Chademo connector for DC as used on some older Nissan and Renault vehicles - essentially obsolete now although most DC chargers still have it.
Early model Tesla vehicles misappropriated the Type 2 for DC charging with no extra pins, with the result that Tesla superchargers could only be used with Tesla vehicles.
However newer Tesla cars have the same CCS connector as everyone else, and they are refitting their Superchargers so that other vehicles can use them.
Those with the older Tesla cars can buy an adaptor from Tesla which converts CCS to the Tesla Type 2, so they can use any CCS DC charger.

but as electric cars on the road increase, we are likely to see people waiting their turn to charge cars when the car in front of them in the queue is only taking a ⅓ of charge available.
No, as charging an electric car is park, plug in, go do whatever you were there to do. There is no waiting around for anything - no one with a EV plugs in and then stands next to the vehicle for a couple of hours waiting for it to charge.
More public charge locations are certainly required, and eventually most parking spaces will have one.

This whole idea of 'queuing up' is what people with petrol and diesel vehicles do, because that's the only way of filling them with fuel.
It's also what everyone has been doing for the last 100+ years, and old habits are hard to get rid of - but EVs are not used in that way. For most of the time, it's charge little and often.
The 22 kW EV charge point is out side out workshop, we see on a regular basis how people are milling around their car clearly waiting for enough charge to get into the car, there is a museum next to the charge point, but for Father Christmas specials that is rarely open.

In the main the drivers of the electric cars are there to ride on steam trains, and it depends on time of year etc, but of late the trips are for around an hour, and a train leaves every hour and a half, so there is around ½ hour overlap between cars coming in and leaving, a busy time for railway staff trying to find new arrivals car parking space before the last group has left.

It has been noted that the drivers of electric cars seem to hang around, I assume to get enough charge to get safely home. To begin with when I started working at the railway there were two or three regular customers and most the time there was always a charge point free. But as time has gone on we are seeing both points in use, some are clearly en-route, and not riding on the railway, and the grab some food and drinks but are clearly waiting to get enough charge to continue their journey, being in the heart of mid Wales there are not that many charge points, and some are at a caravan site which is not open in the winter, even petrol and diesel there are not that many filling stations, and some steep hills on the way to the coast and once they get to the coast there will be more people wanting the few charging stations there are.

In the main as said people stop for either one or two hours, there is no other charging point going into Wales within 26 miles i.e. one hours charge, but loads within 78 miles, the chart was a Nissan Leaf, people tend to be going on holiday or returning and to have visitors spend time in our shop waiting for the car to charge or going on trains trips is what we want, but what we don't want is to upset people telling them there is no charge point they can use.

This Christmas with Santa trains I was told a few time our railway had been selected as it had EV charging points.
Interesting reading, it seems this subject is yet another case of the difference between theory & reality.
With respect to 'Flameport' yes those of us with ICE powered cars do queue, but usually only for a few minutes.
Thankfully by the time the motoring world has succeeded in 'changing it's habits' I shall be, at the very least, long past caring :p