Electric car and in laws.

[Cowcheese]

My in laws are here visiting in their new electric car. They’ve plugged their car in every evening for the whole week using an extension cable. Never once offered us money to pay for this, or even asked us - they just plug it in. If it was just one night of charge I wouldn’t mind, but every night for a week? They are wealthy and holiday all the time, we are struggling to hover above the breadline. How much does it actually cost to charge a car and why is it assumed that’s it’s ok to do this? It’s not the same as just charging your phone is it. Am I being cheap by letting this bug me?

We’re British Gas and I’ve just had an email about this ! Although it does say when it’s sunny as well🤣. Also get half price Sundays and 5 hours cheap at night , saved an absolute fortune compared to petrol .

It's a great idea, isn't it- partially solve energy storage issues from renewable sources by further incentivising the population to use their own batteries- on- wheels 💡

I imagine they’d settle their bill when leaving. But rude not discuss it though.

I think they should be paying, but it's more likely to be a case of them not even thinking about it than them being cheeky - if they're comfortably-off then they may not even notice the cost of charging at home (because there's no separate payment for it, unlike petrol/diesel) and therefore think of it as basically being free, even though it's clearly not.

If your energy tariff charges the price-cap rate, then that's £0.245/kWh. I think most modern EVs have a way to see how much energy they're being "filled up" with, so it'd just be a case of multiplying that by £0.245. Or you could work it out some other way (e.g. if they have a car with a 40kWh battery and they're charging it from 30% to 80%, then the total charge added is 50% of 40kWh = 20kWh = £4.90)

This

Regardless of how much it costs, they are using something of yours without asking

They’re family and you’re hosting them, it would seem very unkind to charge them.

Presumably they aren’t driving miles and miles every day it will be a few pounds each night.
The additional hot water they are using will likely cost more.

You will very likely have an electric car in the near future and will charge it at their house. These things all balance out.

I drive an electric car.
Unless they are driving for hours every day it probably isn't costing you more than a couple of quid an evening. Do you know the cost per KWH of your tariff?

For example my electric car is small - range of about 130 miles and a battery of 38kwh. My KWh price at night is 7.5p per KWh so it costs me £2.85 to completely fill my car from empty.

At a public charging point you'd be paying 70p per KWH so the same charge would cost me over £20.

What is worrying is doing it on an extension cord - that could very easily cause a fire. You can buy long car charger cables with a 3pin plug, they cost about £70.

Why don't you open a convo with the in-laws about the cost benefits of running an elec car and ask them how much it costs to charge each evening if you are home charging? Then you'll all be on the same page.

Do you have a smart meter and can you see on your app
what you were spending a day before they arrived
how much you have been spending a day since they have been there

that would be your answer

Assuming they're using an extension cable which is rated for 13A of current (i.e. 3kW), how is charging (probably at 2.25kW or similar) going to risk a fire?

That's not true. You can plug the car's charging cable into an extension cord, provided you follow normal safety precautions.

Honestly, why do people just make stuff up on here?

I charge at home 99% of the time from a standard plug, so I did get my electrics checked. However, an EV on a standard plug has a similar draw to a washing machine or a clothes dryer. Even some fridges run at that rate.

That's because petrol costs occur in a huge lump sum.

Half the point of an ev is that you don't have to waste time running around to fill it up. You just go home and plug in. It becomes one of those things that just become a routine.

We have an electric car and the manufacturer's instructions were very clear - do not use standard extension cables for overnight charging due to the risk of fire, and if you absolutely have to, you should only use a specially designed extension cable. If you google EV charging you'll find the same advice in many places:

https://www.carsloth.com/advice/ev-charger-extension-cables

https://pod-point.com/guides/should-you-charge-an-electric-car-with-an-extension-cable#:~:text=Summary,faults%20which%20could%20cause%20fires.

https://blog.evbox.com/uk-en/how-to-safely-charge-ev

But it’s still costing the host money, that they wouldn’t be using on a petrol / diesel guest. It’s cheeky to assume, maybe when we go visit the in-laws dh should siphon
his mams car.

my husband got a proper electric charger installed at my sons house a few months ago when he go his new car - it was free from BMW

he has a new BMW i4 charges it twice a week and it cost him around 25 a week

compared to 70 -80 a week on his previous car

he has an app that tells him how much he has used and then put that money aside to give to my son each month

Charging on a regular three pin is dangerous and big fire risk

Me too 🤗

There will be hardly any domestic fridges that run at 10A continuously for 10 hours. Maybe industrial ones.

Tumble driers probably the closest regular portable appliance, but even they don't run for the length of time a car charger will. Appliances obviously have to be fused at peak current draw (neglecting stuff like inrush currents of course), but the fusing does not necessarily represent the average power consumed over a long time duration. Provided all the wiring and sockets are good 2.5kW is fine for long periods. But in domestic situations maybe people have not checked that that socket in the garage that is normally used only for the lawnmower is in good shape.

My granny charger is switchable between 5A and 10A and I actually bothered to check out the temperature rise in the socket and wiring with an FLIR camera. On 10A there is a noticeable rise in temperature when running these things and I consider the wiring in my place to be in very good shape. I have a crappy cheap construction 2kW portable heater I got for about £15 online and that really does heat the plug up, so much so I will only run it on 1kW max. I suspect the wiring on it is not rated high enough.

I don't get the issues people claim with extension cables. If it is rated at 13A and properly built for that as most decent quality ones are then it should be fine. Daisy chained or not. Obviously there is the extra contact resistance in the plug, but provided the plugs and sockets are in good shape and wired correctly it shouldn't be an issue. As I think you pointed out earlier though, if you coil up wires then that is going to create inductance and get enough inductance then that could really cause issues. That's why a lot of the very long coiled extension leads that retract onto a reel have lower max current ratings.

Are they allowed to shower and charge their phones?

People using those layzspa and pool heaters have been burning out sockets too just as some car leads have been. Better safe than sorry when it’s something like that plugged in while your asleep.

I think I would enquire, what the car usually costs to charge so you can be prepared for your next bill, this should give them a good indication that you're struggling without saying it explicitly, if that's something you want to avoid.

Ideally your DP needs to ask, or at least be aware you're going to ask.

Plugging it in with a normal plug will be charging it so slowly it won’t be costing you much a all.

I never charge mine while I am asleep or when I'm out.

The problem with sockets though is that people are just used to using them without thought. The whole thing is supposed to be "plug it in, it works". which is fair enough. Until it doesn't.

This. 100% this.

1. How many miles are they driving every day?
2. Are you sure they haven't cleared it with your DP?
3. Would you be as pissed off if it was a friend doing this?