EV charging point

checkly

I have a detached garage which contains a plug socket.  I am interested in installing an EV charging point in the garage.  I don’t want to use the plug socket for charging as this would take too long.

My questions are:
1) Can this power source within the garage be used to install a separate EV charging point?

2) If so, what would be the approx. cost of this?

Thanks 

ElefantEd

A proper (7kW) charger would probably need a new cable - 30Amp, heavy duty.  If you get an electrician to do this, inclduing the cost of the charger itself, about £800 I think.

An ordinary domestic type socket can only deliver 13Amps (max) and presumably is on a standard ring. So, just as if you were installing a shower or an electric cooker, you need beefier, dedicated wiring to enable it to take the load. Depending on your current set up you might also need to upgrade the fusebox. Your electrician would advise about this of course.

Disclaimer: I am not an electrician!

checkly

So would the cable from the fuse board to the garage need to be dug up and replaced??  Tricky and messy, as it runs under kitchen and patio!!!!

Jenni_D

What size MCB/fuse is protecting the feed to the garage? A 7KW charge point will require a peak feed of 33.8A (if mains voltage is at the lower limit of 207V; nominally 30.4A at the rated 230V).

What size cable is feeding the garage? (I think a 7KW charge point would required 6 mm2 minimum).

Is the cable already armoured or running through ducting? (If not then it may already be a non-standard installation).

Final question - what charging rate does your intended car support? (I have a Volvo PHEV on order - the car itself restricts the charging rate to 3.7KW irrespective of the capability of the charge point. As it happens I'm getting a 7KW charge point installed anyway for future-proofing).

DrEskimo

checkly said:

So would the cable from the fuse board to the garage need to be dug up and replaced??  Tricky and messy, as it runs under kitchen and patio!!!!

Not replaced, you would just need to run a new cable from the consumer unit to the garage. That can take any route you want.

Car_54

DrEskimo said:

checkly said:

So would the cable from the fuse board to the garage need to be dug up and replaced??  Tricky and messy, as it runs under kitchen and patio!!!!

Not replaced, you would just need to run a new cable from the consumer unit to the garage. That can take any route you want.

Any route you want provided it complies with the regs ...

ElefantEd

Car_54 said:

DrEskimo said:

checkly said:

So would the cable from the fuse board to the garage need to be dug up and replaced??  Tricky and messy, as it runs under kitchen and patio!!!!

Not replaced, you would just need to run a new cable from the consumer unit to the garage. That can take any route you want.

Any route you want provided it complies with the regs ...

Which is why you need to ask an actual electrician what is needed, one who can see what the options are. But as I said, installing a charging unit is in the hundreds of £s range - ours was about £600 IIRC, but that was about 8 years ago. It needed an armoured cable running from the fuse box to the charging unit, about 8m long all told.

Chris_English

What car are you going to be charging, and what sort of use will it be getting?

I ask as I had a similar issue (13A socket only) and while it was absolutely useless for my Model S if I ever planned to come home with a low charge and have a long trip th enext day, it's absolutely fine for the electric Smart which we have now.

This one charges up fully overnight, but as it tends to do no more than 15-20 miles on any given day even sticking it on for a few hours in the evening would be enough.

We're still going to get a proper unit wired in to the main fuse box, as it's free (came with the car) and means that we do have the option if running an electric car with higher needs in the future, but for now the current setup us absolutely fine.

born_again

Its not just the cabling etc.
Op needs to know what fuse is installed at meter and if it's a linked supply. Both of which can cause problems with EV points being installed.

Jenni_D

born_again said:

Its not just the cabling etc.
Op needs to know what fuse is installed at meter and if it's a linked supply. Both of which can cause problems with EV points being installed.

Good point - and any competent home charge point installer should be asking relevant questions of the customer to ascertain if the request is even feasible.  

checkly

Jenni_D said:

What size MCB/fuse is protecting the feed to the garage? A 7KW charge point will require a peak feed of 33.8A (if mains voltage is at the lower limit of 207V; nominally 30.4A at the rated 230V).

What size cable is feeding the garage? (I think a 7KW charge point would required 6 mm2 minimum).

Is the cable already armoured or running through ducting? (If not then it may already be a non-standard installation).

Final question - what charging rate does your intended car support? (I have a Volvo PHEV on order - the car itself restricts the charging rate to 3.7KW irrespective of the capability of the charge point. As it happens I'm getting a 7KW charge point installed anyway for future-proofing).

Thanks for that - but I am an absolute numpty when it comes to home electrics so unsure how to go about answering the questions!!  Know where the fuse board is but unsure how to read it.  Do I just measure the cable coming into the garage?  Unsure how to tell if it is armoured or going through ducting!  Don’t know what a linked supply is!!!  Sorry for being such an amateur!!

Not sure what car to get yet if installation of EV point is going to be such a hassle.  Will probably call in an electrician and get their view.