Granny charging - only option - will it be enough?

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Deleted member 7134

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Still in process of working towards getting my MG5 LR but I think I've hit a big snag :(
Basically my garage, where I thought I would be charging, is away from the house (i.e. not attached or even that near) and almost certainly has the wrong grade cabling + power supply for a home charger installation there. House is directly onto street, so no good for home charger there either.
That leaves me with just the granny cable, plugged into garage for home charging.
So my question is, will that be enough? Is it recommended to only use the very slow charging, long-term?
 
It's all I use these days. Didn't worry about it when I first got the car as charging was primarily at work. Now almost always work from home so only charging via granny cable. I do usually only charge at night between 12.30 and 4.30 though so do a couple of charge nights a week. This is for a 40kw leaf but all Ev's would have a similar draw on a granny cable.
 
Hi @Tommy .
I would get a spark to check the incoming cable to your garage first, before you right it off !.
A lot of members use a Granny charger on a regular basis without any trouble at all.
It depends on your usage case really.
Because the charge time is a lot slower than a wall box ( about twice the time ) you could be waiting a while for it to finish, unless you charge over night of course.
A wall box is a better option, but it is what it is !.
 
Tommy said:
Still in process of working towards getting my MG5 LR but I think I've hit a big snag :(
Basically my garage, where I thought I would be charging, is away from the house (i.e. not attached or even that near) and almost certainly has the wrong grade cabling + power supply for a home charger installation there. House is directly onto street, so no good for home charger there either.
That leaves me with just the granny cable, plugged into garage for home charging.
So my question is, will that be enough? Is it recommended to only use the very slow charging, long-term?
Click to expand...
You could use the granny charger off and on, I suppose, but if you buy a 7kw charging cable, you could charge up for free at a Tesco or use an occasional high power charger at a local charging station.
I am another one who only uses a granny charger!
 
How much do you get in from charging overnight? My daily commute is 90 miles round trip, probably should've mentioned that in original post ;)
 
bwanamdevu said:
You could use the granny charger off and on, I suppose, but if you buy a 7kw charging cable, you could charge up for free at a Tesco or use an occasional high power charger at a local charging station.
I am another one who only uses a granny charger!
Click to expand...
I'll be getting a type 2, is that what you mean when you say 7kw cable? I'm new to all of this and getting a bit twitchy about not being able to squirt enough electrons back in overnight :)
 
Lovemyev said:
Hi @Tommy .
I would get a spark to check the incoming cable to your garage first, before you right it off !.
A lot of members use a Granny charger on a regular basis without any trouble at all.
It depends on your usage case really.
Because the charge time is a lot slower than a wall box ( about twice the time ) you could be waiting a while for it to finish, unless you charge over night of course.
A wall box is a better option, but it is what it is !.
Click to expand...
Yeah, worth checking you're right.
 
Tommy said:
I'll be getting a type 2, is that what you mean when you say 7kw cable? I'm new to all of this and getting a bit twitchy about not being able to squirt enough electrons back in overnight :)
Click to expand...
Yes Tommy. An overnight charge should be enough, maybe 10pm to 7ish - more than enough.
 
Tommy said:
How much do you get in from charging overnight? My daily commute is 90 miles round trip, probably should've mentioned that in original post ;)
Click to expand...
You should be ok, the only downside being that you can't take advantage of the cheap tariffs (e.g. Octopus between 12-4am) when they become widely available again.

With a 7kw charger you can get more charge into those batteries during the cheaper hours. Even using the granny it'll be cheaper than an ICE vehicle.

I'd do as others have said and get an electrician to check your garage wiring, you may be surprised and it's ok for 7kw. If not, get them to check what's there, maybe fit a new socket so the connections are tight, and give the granny a go!
 
JCFlippen said:
As mentioned I would get your garage supply checked as you will be using a 10amp load for long durations - will the wiring take it?
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You mean even with just the granny cable that still might be too much for the garage wiring?
 
Tommy said:
You mean even with just the granny cable that still might be too much for the garage wiring?
Click to expand...
Yep, the granny cable is pulling 3.5kw for hours at a time unsupervised. The feed from the house to the garage and indeed from the socket in the garage to the car if you need an extension lead, both need to be in good condition and heavy grade enough to do the job. You'll feel the plug getting hot even if it's all in good nick and rated high enough.

/edit I should say it's very possible that you're fine, but get it checked anyway to be safe.
 
5teep said:
Yep, the granny cable is pulling 3.5kw for hours at a time unsupervised. The feed from the house to the garage and indeed from the socket in the garage to the car if you need an extension lead, both need to be in good condition and heavy grade enough to do the job. You'll feel the plug getting hot even if it's all in good nick and rated high enough.

/edit I should say it's very possible that you're fine, but get it checked anyway to be safe.
Click to expand...
Gosh, I never thought going electric would be such a falafel.
 
The Smart Home Charge gives a much lower value of power drain on the MG5LR when using the granny charger………

Standard three-pin plug2.3kwHome26.5 hours
 
Would it be worth upgrading the supply to the garage? Might cost a bit more and not sure how far garage is from house is, but worst case would ensure you are safe with the granny charger and at same time it could allow you option of wall charger?
Other option is to look for any free chargers in supermarkets and places you would usually. visit and adopt a gradual topping up through week?
 
5teep said:
Yep, the granny cable is pulling 3.5kw for hours at a time unsupervised. The feed from the house to the garage and indeed from the socket in the garage to the car if you need an extension lead, both need to be in good condition and heavy grade enough to do the job. You'll feel the plug getting hot even if it's all in good nick and rated high enough.

/edit I should say it's very possible that you're fine, but get it checked anyway to be safe.
Click to expand...
The granny supplied by MG pulls 10a (approx 2.3kw) so is very similar to an electric convection radiator being plugged in (minus the heat transfer through the wire from the elements).

3.5kw is nearly 15a, you'll struggle to find anything that draws that much power fitted with a standard plug!
 
I used the granny for a couple of months before I got my 7.5kw unit.
The granny does not draw 3.5kw it is about 2.2kw.
You could get the Ohme unit from Octopus and ask them to set it at a lower current say 16A it is a safer way to do it.
The type2 lead you should get is 32A and maybe 10m to reach round bays that have been ice'd😄.
Oh and the car does the charging, the granny is just a piece EVSE😉
 
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It really depends on your average daily use and if plugging in as Granny Charger every evening and using a timer to benefit from the 4 hour window on Octopus Go tariff will be enough for you and if the hassle of charging this way makes you frustrated with EV ownership.

You could indeed seek out supermarkets with free or subsidised Type 2 (7kW) charge posts I did this for the first couple of months while waiting for first the Smart Meter to be installed then the tariff switch over to take effect and my home charger to be installed. BUT it was a hassle and a Type 3 4 hour charge on Octopus Go can add 100+ miles overnight.

The other consideration is that if you are only using the 10 amp charge of a Granny Charger it can be difficult to get a decent Balance charge once a month for good Battery health.

Even though a Granny Charger is only charging at 2.4 kW the 3 pin plug can get quite warm and if the socket in your garage is just a spur taken off your Ring Main in the house regularly using it this way for hours and overnight is not to be recommended. The socket you plug into should be a socket on the Ring Main so it is supplied from two directions to share the load.

If a socket in the detached garage is your only option speak to a qualified electrician and consider a dedicated cable back to your consumer unit in the house and fit a Commando socket in/outside your garage and use an Ohme charging cable with a Comando Plug which I believe are still available via Octopus Energy with substantial discount c£200. You can then schedule the charging with the Ohme App.

Octopus Energy are certainly a brilliant company to deal with as they are not only competitive and EV friendly but yesterday evening at 21:18 I requested a refund of £500 as my account balance had built up and 4 hours later at 01:20 I received an email confirming that the refund had been sent for payment.

If you haven't already switched to Octopus Energy get in asap and then switch to Octopus Go for the 5p rate for your overnight charging. Use my referral code below and we can share £100 that's £50 for you and £50 for me
share.octopus.energy/zappy-guppy-175
 
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