@rusty, you've posed a very important question and highlighted admirably the issues faced with the decision. As we've seen on one or two other threads, at its most basic an EV could be charged at 7kW via a commando socket, negating all considerations of network connectivity and so forth. However, most of us do find the extra functionality of a wallbox useful, so the issues you've outlined inevitably emerge.

Firstly, box siting. You've already found two possible spots and from a purely technical point of view it's just a matter of how to route the cable from your consumer unit to your wallbox so that the wallbox is near enough to the car to plug in. Bear in mind, though, that despite its name a wallbox doesn't have to be mounted on a wall; several wallbox manufacturers include in their marketing images at least one shot of a wallbox mounted onto a pillar which can be installed much closer to the car's parking spot.

Secondly, network connectivity. Living in a blackspot as I do, I've long discounted the idea of using anything that relies on the mobile network. Apart from potential reliability issues, it means the wallbox's route to the Internet is independent of your home network and so you are totally tied into the manufacturer's cloud solution. I also don't like wifi either since making connectivity reliable can involve more effort than one might like and even then can still suffer from interference. The only form of connectivity I am comfortable with is some form of physical wiring, but that definitely narrows down the choices. I ended up with my MyEnergi Zappi for exactly this reason and have been very happy as a result, although changes to the way the company provides technical support (more on that in a moment) I would personally actively avoid MyEnergi now.

One unit that I have heard about and that I would probably go with now if my current box died is the NexBlue Point 2. I hasten to add that this is not a recommendation since I haven't actually laid hands on one so far and so have no actual experience of it. However, it does have an Ethernet port as standard and is (as far as I can see) unusual in having the option for an RS485 connection so the unit can be controlled locally via Modbus. That may well mean very little to you - I have no idea - but from my point of view that means that if the manufacturer were to go bust then the unit could still be kept fully operational by purely local communication. I would be very interested if anyone knows of any other units that come as standard with both RJ45 sockets and RS485 capability.

Thirdly, the companies themselves. If you do as most people do and control your car charging either via the wallbox's bundled app or the car's app then all your functionality is at the mercy of one or both of those two manufacturers. At its worst, we could see another GivEnergy fiasco with app functionality either being withdrawn altogether or made a chargeable "privilege", but many more of us will at least find we have to call upon some form of technical support. I mentioned my wallbox is a Zappi, and fairly recently MyEnergi have actively stopped end users from being able to ring them up - even to the extent that if you manage to find and call the number given to installers for support then MyEnergi will stop the call as soon as they identify you're not an installer. It's an AI bot or nothing if you want help and God help you if you want to get in touch with Customer Services to raise a complaint. As a result, I feel that manufacturer reputation - particularly for service and support - is hugely important in your decision, unless you go down the far more hands-on route of cutting out manufacturer systems altogether and controlling entirely locally.

As for later integration with solar panels and inverters, most wallboxes are already designed to be incorporated in this way so I doubt your wallbox-first approach is likely to be a big issue. However, it would be well worth mentioning it to the installer to ensure that anything that could usefully be added at installation time is included.

There are many other details that will crop up as you discuss all this, but hopefully the above gives a good starting point. Which EV are you going to get?

I have installed an EVSE. I'm French, so I have no idea about the bureaucratic red tape or special subsidies you'll get.

While it is usually called "Wall charger" an EVSE contains no charger. The charger is in the car. 

What's inside is a special Residual Current Detector that will detect DC and high frequency leaks, a contactor, a connector, and a 2€ microcontroller. The most expensive part is the connector. 150-200€ would be a honest price for the whole thing. Obviously calling it "charger" and making it seem complicated inflates the price.

The EVSE communicates with the car using an extremely simple protocol called SAE J1772. First, it detects the car is plugged in. Then it checks the RCD for leaks, activates the contactor, and sends a PWM signal to the car to tell it how much current it can use. That's it, there are no other forms of communication: in particular, the car cannot tell the EVSE about its state of charge, so if you want to charge it to X% then... you have to tell the EVSE to stop after some number of kWh, or use the car app.

Waterproof buttons and displays cost money, and money is expensive, therefore most EVSEs have no controls at all. Mine just has a RFID reader.

Many EVSE manufacturers have fully embraced the enshittification trend, so if you do not pay careful attention to what you are buying, this is what you get:

- All configuration through buggy phone app that won't work on your next phone once the manufacturer stops maintaining it

- All "smart" features go through cloud that requires internet connection and will stop working (or be on monthly subscription) sometime in the future

- Obviously, most of the time, there is a lock on the connector, for "safety". If you have a Type 2 plug on your car, there is also a lock on the car side. In other words, if you need your car, you are going to have to unlock the locks to pull the cable out. Depending on the device, this may require using the buggy app, or the cloud, or swiping your RFID tag, or other kind of stuff that probably won't work if the internet is down.

- If it connects to the internet, it will probably update its software and brick itself, or the upgrade will try to bill you for previously free to use features

See what I mean?

If you get solar, then as everything else in solar, nothing is compatible with anything. This means if the EVSE tries to be smart, it will want its own current transformer or smartmeter, but it will not know about the battery in your PV system, so it will probably not work.

So I got an EVSE without internet connection and with a Modbus control port. Modbus is wired, delightfully insecure and obsolete, which means there's nothing the manufacturer can do to annoy the user. Charging current is controlled via Modbus, that can be done with Home Assistant and a RS485 dongle for example. It's the ABB Terra. I don't recommend it, because the phone app is absolute garbage, but you get the idea.

There is a project called evcc, it is software that can control many different brands of EVSEs.

@majordennisbloodnok Thank you for your insights, you seem to have hit several key ownership points at once. I too am somewhat concerned about tying into a particular manufacturer/supplier support for similar reasons as you state.

I note that the with one supplier 4G support only lasts for 3 years and then becomes a paid for option without which the unit seems to revert to a max charge only mode. Not ideal, and given that we have poor and unreliable 4G anyway, then I will probably discount these.

I was not aware of the customer support issues with the MyEnergi/Zappi range, but that would put me off. As you say reputation and customer support are a high priority as is a local installer base.

I’m not mad keen on WiFi, due to the thick walls we have both externally and internally. Fixed wiring would have been better but somehow got forgotten about when refurbishing. I’m particularly annoyed about failing to put an Ethernet link into the duct to the garage when the new mains cable was laid. It was in my head, just never got translated to the specification. I did say it was painful. Not sure that the wife will let me string cables around the new refurb.

There seem to be a few that can be specified with a wired Ethernet connection, e.g. Simpson-Partners Home Series, Hypervolt Home 3, etc. No idea about RS485, although I do know what that is. Never played with Modbus, but again, I do have an idea of what it is.

Simpson-Partners have started my spreadsheet for me:

https://www.simpson-partners.com/charger-comparison

This might be useful. I will add the NexBlue Point 2 to my list. Coincidentally I came across these from a review site only a short while ago, but have not been through the details yet.

I note that the comparison claims that the Simpson-Partners Home Series V3 (and Easee One to a certain extent) support wireless load management and OCPP (if that is what you infer for independence of supplier cloud services). Wireless load management might be useful if it means that I could site the unit in/on the garage whilst putting the CT in the meter cupboard, range and replacement/upgrade of the garage CU issues notwithstanding.

I also note that the S-P unit also claims LoRa support. I have an ongoing never started DIY project to try LoRa for remote power switching at the bottom of the garden.

Post mounting further into the driveway would be nice, but would require, I think, too much additional trenching (and we’ve just had a rather nice porcelain path laid right in the way) to be a consideration. I feel the need, if we go down the wall box route, for the simplest lowest cost option that still meets some minimum service and use criteria.

The wife will be getting a Kia EV2 Air. As we are about 11 miles from the nearest reliable public charger, although she will regularly be near some other options that are about 20 miles distant, that is why I was looking at a wall box as an option. I may consider a “granny charger” as an initial fallback if it looks like it will take me too long to organise a wall box (prevarication is my middle name), limited to 10A and with the wiring checked and a 13A EV rated socket probably inside the garage. PEN protection worries me slightly in this case.

@rusty I'm following with interest as we too are considering an EV, although you are further ahead in this journey having actually ordered one.

We have similar issues around wifi, with internally insulated 2-3ft stone walls. Consequently I have wired the house for Ethernet and try to physically connect as much as I possibly can.

I had shortlisted the Hypervolt Home Pro 3 charger for it's ability to support Ethernet connection, and as it is compatible with Octopus Intelligent Go tariff.

I will add a further spanner into your considerations, as you mention you may get a battery down the line. This makes where the EV charger connects to the incoming supply important, as if the battery sees the EV charger as "house load", you can end up charging the car from the house battery which is not what you may intend (charging one battery to charge another). For this reason, connecting to the incoming supply on a henley block before the main house CU may be preferable - for this reason I'd rule out connecting it to the garage supply, for example. I see this issue crop up frequently on FB groups for Powerwall owners.

Regarding installers, I tried to get a quote from national installers such as Smart Home Charge who were recommended and found that as soon as I said I had a battery, they were unable to provide a quote for installation, presumably because of the complications above - I guess they want the low hanging fruit, not the complex stuff, but they may be worth a try. My local installer who installed my Powerwall recommended a Tesla Wall Connector as it would integrate well with my existing setup (all controlled in one App), but I found out Tesla do not support charging from excess solar unless you also have a Tesla car, which we are not planning to get. In other words, it is truly a minefield out there.

I've also considered the Commando socket route @majordennisbloodnok mentioned, combined with one of these, available in 6m, 10m and 15m lengths and can also double as a granny charger:

https://www.amazon.co.uk/dp/B0H9Y716C2

You can turn the socket on/off in the house via an MCB or isolator switch, and schedule charging times in the App, plus limit current draw which almost gives sufficient manual control to charge from excess solar (especially if you have a house battery to provide a little buffer). It should also work with Intelligent Octopus Go if the car is compatible.

Posted by: @rusty

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I’m not mad keen on WiFi, due to the thick walls we have both externally and internally. Fixed wiring would have been better but somehow got forgotten about when refurbishing. I’m particularly annoyed about failing to put an Ethernet link into the duct to the garage when the new mains cable was laid. It was in my head, just never got translated to the specification. I did say it was painful. Not sure that the wife will let me string cables around the new refurb.

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Agreed. Fitting structured cabling would be a good idea and there are options that might make that still feasible even after your refurb. When you see a professional do an installation, it's amazing how voids you never even expected to be useable get incorporated into amazing invisible cable routing to extremities of the building. Even if there aren't any, it can often be simpler and tidier to go out of the house and use some discreet external ductwork and lollipop joints to come back into the building where you need. Installing structured cabling is an art form.

How long is the duct run from house to garage? If it's not horrendously long, it may be possible to use some network rods to get some cord down next to the mains cable so some ethernet cable can be pulled through. Note, of course, that if it's that close to (and parallel to) mains cable, it'd be necessary to ensure the ethernet cable was shielded twisted pair.

Posted by: @rusty

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There seem to be a few that can be specified with a wired Ethernet connection, e.g. Simpson-Partners Home Series, Hypervolt Home 3, etc. No idea about RS485, although I do know what that is. Never played with Modbus, but again, I do have an idea of what it is.

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I view the inclusion of an ethernet port as a key differentiator, and wouldn't buy any wallbox that didn't have one. However, let's still not forget that adding wifi access points is a valid option for providing a reliable signal where you need it without the degradation of performance that can sometimes come with mesh networks. If you find a wallbox that does everything you want but where wifi is the only option, don't discount it immediately.

As for modbus, it's all about being able to use that two-wire RS485 physical connection to control the wallbox (or inverter, or heat pump etc.) directly without needing the unit to talk to something on the internet that you then try to access over another Internet conversation. I happen to use modbus to control my inverter and so even when the manufacturer's site is unavailable I'm still getting my reliable updates from the inverter every 30 seconds. As for a wallbox, it would make it feasible to incorporate it into a wider "smart home" setup that didn't rely on the wallbox manufacturer at all.

@old_scientist mentioned that where a wallbox is installed is important and he's right. However, I do have mine seen as "house load" so that it can draw from solar PV via the inverter and therefore only import from the grid any remainder necessary. The way I stop charging the car from the home battery is that I (or more precisely my Home Assistant) set the home battery's minimum state of charge to 90% whenever the car is charging and back to 10% again whenever the charging stops. Modbus is just a means of communication with the wallbox and it's what you do with it that matters; for many people, they'll never get their sleeves rolled up enough for modbus to matter to them.

Posted by: @rusty

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I note that the comparison claims that the Simpson-Partners Home Series V3 (and Easee One to a certain extent) support wireless load management and OCPP (if that is what you infer for independence of supplier cloud services).

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I see OCPP as very similar to Open Banking in the financial world; sharing of data with third parties rather than anything else. My comments about independence from cloud services are more centred around trying where possible to have conversations with my bits of tech across my local network or via physical local wires rather than needing to go out onto the Internet in the first place. Ideally, if an errant jackhammer were to sever my fibre connection I would want to still be able to control my heat pump, inverter, wallbox and so on, and such a setup then also necessarily makes me independent of any manufacturers trying to play silly willy-waving power games.

Posted by: @rusty

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The wife will be getting a Kia EV2 Air. As we are about 11 miles from the nearest reliable public charger, although she will regularly be near some other options that are about 20 miles distant, that is why I was looking at a wall box as an option. I may consider a “granny charger” as an initial fallback if it looks like it will take me too long to organise a wall box (prevarication is my middle name), limited to 10A and with the wiring checked and a 13A EV rated socket probably inside the garage. PEN protection worries me slightly in this case.

IMHO, a granny charger can only ever be a fallback given how long it takes to charge the car to any significant degree. However, I also think everyone should have one even if only to get enough charge to drive to the nearest public charging point. I don't have personal experience of the Kia, but my wife and I were certainly considering one and I've heard good things. The only reason we got what we did was that it was the right second-hand deal at the right time in the right place.

Posted by: @rusty

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I may consider a “granny charger” as an initial fallback

I had only a granny charger for the first two years of EV ownership (Kia niro,).  I didn't find the charge time a problem with a bit of planning.  I eventually got a 7kW charger to access octopus intelligent go.  I have to accept it's more convenient, but a granny charger alone is perfectly usable depending on course on your drive profile.

Posted by: @bobflux

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I have installed an EVSE. I'm French, so I have no idea about the bureaucratic red tape or special subsidies you'll get.

While it is usually called "Wall charger" an EVSE contains no charger. The charger is in the car.

I completely concur, the terminology is confusing for most customers, it should just be an EVSE or Level 2 AC Wallbox, as they just manage the supply of AC power and contain relatively straight forward electronics.

I don’t believe that we would qualify for any subsidies now for EVSE installation. Bureaucracy would seem to be just informing the DNO and the usual electrical works certification.

The points that you make about reliance on flakey apps, cloud systems and potential changes in terms and conditions and access rights are exactly the things that give me pause for thought and a slight nagging worry about the devices. In particular I don’t want to wake up one day and find that it’s just an expensive ornament.

Can you not force charging to end and unlock the connector from the car end from within the car? I’m not sure, I think I read that somewhere. I need to check with the owner handbook.

Makes me want to cancel the order and get her a petrol car!

Some of the EVSEs claim battery and solar integration, I will have to look more closely. If we were to go down this route at some future point, then one issue would be that I would want to put solar in as either a ground mount system or on the outbuildings, as the house roof faces East/West, in places is partially shielded by trees and may need to be completely replaced to support the panels. That would be a deal breaker. Unfortunately we live in an AONB, hence I understand that we would need to put in a full planning application for solar ground mount, even though it would not be visible from the road or infringe any of the other restrictions. Putting panels on the garage roof (West facing) and Workshop (South facing) would be preferable, no planning required. That possibly means installing batteries and inverters at the garage and dealing with the control requirements and cable routing to the meter point.

Posted by: @old_scientist

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I'm following with interest as we too are considering an EV, although you are further ahead in this journey having actually ordered one.

No problem, jump in, hopefully this discussion will be useful. The comments and insight received so far have already been helpful to me, thanks all.

Posted by: @old_scientist

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For this reason, connecting to the incoming supply on a henley block before the main house CU may be preferable

I believe that a Henley Block is installed, as the garage/second house sub-main feed splits off at this point. I will try and get a photo and upload it if I can work out how.

Posted by: @old_scientist

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I've also considered the Commando socket route @majordennisbloodnok mentioned, combined with one of these, available in 6m, 10m and 15m lengths and can also double as a granny charger:

That is interesting, I had seen these but discounted them for the arbitrary reason that the garage CU would need replacing to add a 32A feed and possibly the PEN fault protection, plus I was fixated on the load management to avoid overloading the main supply. I suspect that it would be cheaper to get an electrician into replace the Garage CU and run a cable through to a commando socket on the wall and use one of these. Presumably timer delay would be required to utilise time of day (or night) tariffs. Something like this I guess, but with a 3-pin adapter and care with the current limit if only using it in granny mode:

https://voldt.co.uk/products/type-2-32a-blue-commando-socket-1-phase-adjustable-8a-32a-7-4kw-charging-cable?variant=47887787819342

Posted by: @majordennisbloodnok

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How long is the duct run from house to garage? If it's not horrendously long, it may be possible to use some network rods to get some cord down next to the mains cable so some ethernet cable can be pulled through.

I was hoping that the electrician would route the underground ducting in a shallow loop around the front and side of the house and then along to the garage at the rear/side of the house, say 15m. Instead he ran it in a tortuous route tight into the side of the house, intricately following the outline of the new bay window, under the new kitchen step and thence to the garage under the path (now covered by a drainage channel). I think I created fear because there is a shallow laid water pipe in the vicinity. Anyhow, it was a bit of a struggle pulling the mains cable through, so I fear that it might be difficult to pull through another cable, even a thin one.

Posted by: @majordennisbloodnok

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I see OCPP as very similar to Open Banking

Sorry, I looked into OCPP too quickly and misunderstood its reason to exist, more homework needed.

I really value this advice, looking for a system with wired dumb(ish) control would satisfy my need to have some control in case of the disasters that you also envisage.

i have managed to get a mesh node working quite near to the meter cupboard and with decent WiFi coverage outside near the spot on the outside wall that I was considering, hence I’m less concerned (or more hopeful) about installation issues due to this potential issue. Moving the master router and fiddling with the second node position might help further.

Posted by: @rusty

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I had only a granny charger for the first two years of EV ownership (Kia niro,).  I didn't find the charge time a problem with a bit of planning.  I eventually got a 7kW charger to access octopus intelligent go.  I have to accept it's more convenient, but a granny charger alone is perfectly usable depending on course on your drive profile.

That was indeed my thinking/reasoning, just really to add an emergency couple of dozen miles. Not sure of the battery cycle/wear effects of using this routine though. We know somebody else who has gone down this route, so it is doable and I will ask them. I sent the wife out to take a look at the nearest public charger, just to familiarise herself. She had a nice chat with some people using the chargers. Again, it’s somewhat reassuring.

Apologies for the numerous posts, I’m trying to do this on a tablet and it’s making it a pain to get quotes and link the replies. 

I had only a granny charger for the first two years of EV ownership (Kia niro,).  I didn't find the charge time a problem with a bit of planning.  I eventually got a 7kW charger to access octopus intelligent go.  I have to accept it's more convenient, but a granny charger alone is perfectly usable depending on course on your drive profile.

Posted by: @rusty

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That was indeed my thinking/reasoning, just really to add an emergency couple of dozen miles. Not sure of the battery cycle/wear effects of using this routine though

For me the granny charger was the only thing I used.  I let the battery discharge to say 30% before charging for several successive nights.  I only used/use a public charger when away from home.  A good friend of mine with a Tesla does the exact same.  

Posted by: @rusty

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I really value this advice, looking for a system with wired dumb(ish) control would satisfy my need to have some control in case of the disasters that you also envisage.

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As a quick reality check, any wallbox with a display (sadly a minority) and a button or two does allow you to sort out the charging entirely manually. It is only the (majority) units with no buttons or display that rely entirely on an app. I should also say that I have no idea if plugging the car in and then using the car's "charge immediately" function would control the wallbox in any way since I haven't tried doing that; anyone else here who can comment on that?

As for wired controls, they don't need to be dumb at all; they're just local. However, given you don't have a solar array and inverter and perhaps don't have a heat pump either, installing something like Home Assistant just to control the EV wallbox does seem rather overkill. As you said earlier, a commando socket along with some form of smart switch might be a good alternative if simplicity is a priority. That said, we don't really know what your appetite is for tinkering; whereabouts on a scale of technophobe to gadget freak do you sit?