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Hello folks,
I am getting my 3.3kw 2015 Leaf early next week and am trying to get informed about apps, charging stations etc...

Given my car is 3.3kw, is there any point in getting an (expensive) box for my drive? Would that charge any faster than the "granny cable" plugged into any 3 pin socket?

Thanks,
Mark.
 

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30KW Tekna (2017)
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Your granny cable is not very efficient only about 2.2 kw makes it to the car, so a dedicated charger can pull at the full 3.6 kw I think it’s capable of, so a faster charge by far!
 

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I only use a granny lead mind, I’m having a sparky round tomorrow to fit a commando socket and a few other things.

I bought another granny charger with a commando socket and capable of 16amps so should pull the full 3.6kw.
 

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Would that charge any faster than the "granny cable" plugged into any 3 pin socket?
Yes. The granny cable is 10A or about 2.2kW and a charge point is 16A or about 3.6kW.

That alone is 1.6 times faster. The on-board charger is more efficent at 16A, so the real speed difference to 98% is larger.

At 98% indicated the charger ramps down and does some sort of top off charge. That takes about 30 minutes no matter what the car is plugged in to.
 

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Welcome to the forum and A Leaf Less Ordinary.

Ok so this really does depend on what you plan on doing daily mileage wise in your extremely wise purchase. Also battery size could matter.

I've got the 6.6kw 30kwh but am still not totally convinced I need a charge point given the cost. Why?

I do a 48 mile round trip commute 5 times per week. That's pretty much it week days. At 4 miles/kWh that's 12kwh per day or 60 per week.

On the octopus go tariff I get 4hours a night at 5p per kWh. That gets me 8 kWh back per night. Do that 7 nights and that gives me 56 kWh. I'm nearly there.

For me I'm helped having plenty of free charging at Tesco and Sainsbury's nearby, so the 6.6kw means I can easily pick up another 10kwh for free while grocery shopping. That gets me over the line.

What do you plan daily mileage wise? And also any Nissan dealers nearby?
 

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Given my car is 3.3kw, is there any point in getting an (expensive) box for my drive? Would that charge any faster than the "granny cable" plugged into any 3 pin socket?
The keywords here are 'any point'.

There is a good point but it isn't about charge speed.

As has been said, an OLEV funded wall charger will charge at 3.3Kw from a 16 amp or larger supply. A 'granny' will charge slower as the current is limited to circa 10 amps to protect the house wiring and 13 amp 3 pin plug and socket that wasn't designed to pull 10 amps for many hours.

I assume that your car is a 24 kWh version. It is quite rare for a battery to be completely empty before charging and it is good practice to only charge to 100% if the car is about to be driven right away. This means that with a regular modest daily commute you would only need to 'replace' energy overnight for next day's trip. Possibly that will only be half of the cars' battery capacity. And replacing 12 kWh's overnight using either a 2.2 Kw or 3.3 Kw input would be easily completed within six hours anyway. So no problem in normal use of a Leaf 24 using either charge system.

The real issue comes with the potential problem of permanently using a domestic 13 amp socket rather than a properly engineered system with sufficient redundancy and safety built into it. Which is why it will always be recommended to install a wall charger. Having said all that, many EV owners have always used a 13 amp granny lead - including one prominent forum member who is a professional electrician. He says that as long as the house wiring is modern and fitted with a modern consumer unit there is little danger although the risk is still greater than with the proper unit.

If you elect to just use the granny lead please check the plug at the house end after 15 minutes and monitor it every half hour for the first few times to watch for heat build-up as that would point to a future issue. The plug will be fitted with a thermistor device to disconnect the supply if it overheats so there won't be any real danger. But if that is seen it could also signal a problem building up inside the house as well. Very rare - but worth watching for a while.

If you decide to go for the grant-aided wall box solution please also consider fitting a 32 amp box, even though your present car can't fully use that current, because your next EV will certainly be able to take the higher rate and you will be future-proofing the installation. Very little cost implication at the outset but a costly retrofit.
 

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Get yourself a wall box charger. I think of it like another utility supply like water and gas/electricity. When you buy your next ev it will be future-proofed and if you sell the house before then it's a great extra selling point. The grant pays for the bulk of it anyway so you have very little to lose and lots to gain.
Make sure you get an untethered one if you can, it's worth the extra.
Welcome to the club Mark.
 
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It’s really about usage right now. Future proofing is a wild stab in the dark (how many type 1 to type 2 tethers and/or 16A to 32A ‘charger’ ((and cabling) swaps have happened to those who invested in the latest wall boxes a while ago? The mass of dumb wall boxes on eBay suggests quite a few.

I suspect we will soon see a rash of smart dual chargers to address the 2 EV & not retired yet households with scheduling and load balancing and overall with house load management across the 2 (maybe even with Agile etc capability). This is needed if we want cars to be the partial ‘answer’ to off peak excess capacity and load smoothing. Perhaps try to predict how they will be cabled and ‘future proof’ the black worm from meter box to wall box?

Grannies are fine. The circuit and faceplate you intent to use may or may not be. An EICR plus a new decent brand faceplate is probably money well spent.
 

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Discussion Starter #9
WOW, loads of excellent replies, thank you all so much for your time and input!

Having read the comments, I'm englightened to a bunch of other possible issues... so here are the missing facts:

1/ My drive is near the garage (big surprise there) which is now an office. It has a trip switch in it. I don't know how many Amps it can handle
2/ The nearest socket to the car would have to go through a window and the cable would have to be about 10m. I think the cable that comes with the car will be much shorter. From what I read, even high quality extension cords are a no-no.
3/ I don't commute, but go short distances many times a week, probably 5-10 miles a day on average, but occasionally a short trip of about 60-70 miles (so for those I'd want 100% charged)
4/ I have 3.1kw solar panels and during the day, using that power is free, so I will want to charge daytimes. During winter, with much lower generation, I'd be drawing off the grid, so a faster charge would cost more.

Given the distance to a socket and the grant (which I did not know of), an OLEV funded wall charger seems like a sensible idea. I will check out the difference between the different wattage boxes offered.

Thanks people 😊
Mark.
 

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I purchased a supplementary granny EVSE that can charge at all amperages between 6 and 13. (Not sure about chargng rates over 10 from a granny being a good idea but it will do it.) Having the lower rates available means I can charge from solar without drawing off the mains and with less strain on a household supply. I also have a 32 amp wall box should I need to charge faster.
 

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Discussion Starter #11
Hi John,
With your 32A wall box, what type of connecter do you have 3pin UK? - I suppose you have the 6.6kw car?

I also have a 32 amp wall box should I need to charge faster.
 

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At risk of being shouted down, I'll make my normal statement that Type 2 ("Granny") charge points are marginally less safe than dedicated Type 3 ("Wall box") charge points, mainly due to the way that the Earth is handled and also the issue of how waterproof the "brick" in the Granny lead actually is. Particularly with the OP stating that the car is a considerable distance from the house the Earthing issue is significant. Having said all of that I'm not aware of any fatalities yet from the use of Granny chargers.
A number of different models of charge points can handle solar and adjust their charging rates accordingly, so a granny charger is not the sole solution. Think carefully of your needs before investing your money and committing to a course of action.
 

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I have to agree with @dk6780 , if I had off street parking I would defiantly be using a 7kw non tethered charger properly installed and earthed.

It will also be cheaper in the long run as I Doubt my granny charger will last as long as a dedicated charger, but for me it’s my only option at this time.
 

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.......... if I had off street parking I would defiantly be using a 7kw non tethered charger properly installed and earthed.
And I would definitely always use a tethered unit. The faff of fighting with a wet and dirty cable into and out of the boot every time can rapidly become unattractive. Most people eventually buy a second cable for the boot and leave one in the socket permanently with some cobbled together security to prevent theft. Cut out that extra expense and go tethered in the first place and leave the cars' cable nice and clean in its bag in the boot ready for the odd away charge event.
 

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And I would definitely always use a tethered unit. The faff of fighting with a wet and dirty cable into and out of the boot every time can rapidly become unattractive. Most people eventually buy a second cable for the boot and leave one in the socket permanently with some cobbled together security to prevent theft. Cut out that extra expense and go tethered in the first place and leave the cars' cable nice and clean in its bag in the boot ready for the odd away charge event.
Oh i agree completely! However I was assuming an extra lead left permanently attached, sorry I did not make that clear in my post.

Before I got my current setup, the morning coiling a wet muddy cable before work got old fast!
 

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Discussion Starter #17
the morning coiling a wet muddy cable before work got old fast!
faff of fighting with a wet and dirty cable into and out of the boot every time can rapidly become unattractive.
You guys need to move to the south of England, we don't have mud here :ROFLMAO:
My reasoning for preferring the unteathered is that in a few years we'll get a second EV, also having the cable coil next to the box is extra messiness...
Thanks for your thoughtful respones.
 

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You guys need to move to the south of England, we don't have mud here :ROFLMAO:
My reasoning for preferring the unteathered is that in a few years we'll get a second EV, also having the cable coil next to the box is extra messiness...
Thanks for your thoughtful respones.
Im probably further south than many! Right on the coast in Sussex!

It’s posh mud but still mud! ;)
 

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Hi John,
With your 32A wall box, what type of connecter do you have 3pin UK? - I suppose you have the 6.6kw car?
The 32A wall box is on it's own circuit with a dedicated fuse box. 3 pin UK plugs are of course just 13A max (3.3kW.) Yes it's a 6.6kW car.
 
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