Using a normal extension lead outside

[GaryMG4]

A friend of a friend let out their holiday cottage and was left with a £300 electric bill because the renters used the washing machine and tumble dryer for their rug washing business.
I'm hoping that the place I'm staying might be persuaded to install a wall charger for future visits as I think destination charging is the future.

 

[Rolfe]

I think that will come. It is quite a big investment though, so it might take a while before we see a lot of holiday lets doing it.

 

[Grriff]

It's possible to buy a cheap electricity meter which plugs into a 13A socket. This would allow an exact reading of kWh used to charge the EV.
I believe we should be paying. A 7 day holiday 200 miles from home, with 30 miles per day travelling could use 100 kWhr costing £30, which an ICE driver would have to pay.

 

[Rolfe]

You'd have to be plugged in to a granny lead for quite a while to rack up £30 of electricity. For example, if you arrived empty and charged overnight for 12 hours, you'd pick up maybe 80 miles to start you on your holiday. Personally, with the LFP battery, I'd stop at a rapid charger not too far from my destination, then just use the granny charger to top up to 100% and balance. Different if the holiday let has a wall box though, that would be a luxury.

 

[Archev]

Should be okay as a one off situation.
Check on the cable rating, it is printed on the outside sheathing.
It needs to be no less than a cross rating section of 1.5mm.
Larger ( 2.5mm ) is fine, but not any smaller than 1.5mm.
Some of the cheap windup ones are only rated at 0.75 / 1.00mm - NO GOOD !.
This size flex will over heat and is dangerous.
Okay for your Xmas lights etc but that’s it.
If the cable is in good external condition and it gets a little wet, there is little risk here.
It’s the socket outlet that your Granny lead plugs into, that is the vulnerable part that needs to be protected from the rain.
Try and keep the socket outlet off the ground and as a temporary measure, do you have a large plastic storage container that could be used to put over the socket outlet to shield it from the rain ️ ?.
If you intend to use a socket outlet externally, then it should be suitably IP 55 / 65 rated.
This rating covers both dust and water ingress.
As other members have said, monitor the heat being produced at the three pin plug that you are using to power your extension.
The plug top WILL get warm to the touch, which is completely normal, but if it gets mad hot to touch, then stop.
The plug on the charger is unlikely to get hot because it carrying a heavy duty plug and cable.

I’ve used an extension cable with the granny charger outside on a couple of really wild nights and found everything was fine. I have a small plastic toolbox with a secure lid - I’ve a couple of slots cut for the cable in and out. I also try t shelter it under the car a wee bit.

 

[johnb80]

So when you use an air bnb you normally give them an extra tip towards the electric for using the shower, oven and watching the tele?

No because that would be expected that people will have a shower for 15 - 20 minutes, very different to an EV on charge taking 30 kWh additional load, thats not right to expect the owner to absorb that. I personally would be pretty peeved if someone did that to me in a rental property.

 

[tsedge]

Many holiday lets now a policy against granny charging and I think we'll see in the future supplementary charges for electricity use over an inclusive amount or simply charging for the electricity and gas used during the stay.

I'd be happy to be charged for everything I used so long as the rates were clear beforehand and not excessive.

 

[GaryMG4]

Well our host greeted us soon after arrival and noticed we had come in a different car and that it was an EV and asked if we needed to plug in. After a visit from a Tesla owner a couple of years ago he had a 32amp commando socket installed with an adjacent 3 pin so all should be fine.

 

[Rolfe]

Brilliant!

 

[Ruislip Resident]

At my holiday in Cornwall in the summer they had a podpoint untethered chargepoint I could use. They only charged me at the tarrif it cost them. Was about 25p per kwh I think. Made life so much easier.

 

[johnb80]

At my holiday in Cornwall in the summer they had a podpoint untethered chargepoint I could use. They only charged me at the tarrif it cost them. Was about 25p per kwh I think. Made life so much easier.

Very much the right thing to do. I'm installing a charge point at my business premises and I will be charging the unit rate of electricity plus the cost of the equipment spread over a 4 year period. With my current tariff it will be around 32p kWh.

 

[OriginalBigAl]

Going away this week and taking my granny charger to plug in when I get there. Is using a normal 5m indoors extension lead a stupid idea for outside for 1 night?

If you had an ICE car and found a couple of gallons of petrol/ diesel in an outhouse , would it be alright to top up your car?

 

[RichP]

Honestly I’m staggered at the amount of bad advice you’ve been given here. It’s a very bad idea to use an indoor extension lead outside. They’re not designed for it and you’re asking for trouble. And I’m speaking as an electrical product safety professional!

 

[johnb80]

Honestly I’m staggered at the amount of bad advice you’ve been given here.

How about being explicit, where is the bad advice. All I've seen is people recommending 2.5mm2 cable and protecting the socket end from the elements including lifting it up off the ground. Furthermore that if it's on a reel it must be fully unwound.

It’s a very bad idea to use an indoor extension lead outside.

Technically theres no such thing as an indoor / outdoor extension lead, some do have such categories but they just tend to be 2.5mm2 cable and sometimes a cover over the socket as well.

They’re not designed for it and you’re asking for trouble.

How are you asking for trouble with a 2.5mm2 cable, protecting teh socket from weather and having it elevated from the ground?

And I’m speaking as an electrical product safety professional!

Excellent, I'm speaking as a retired sparky with 50+ years experience