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There is more than one solution!

First thing I'd recommend is binning off BG. I've heard a lot of terrible reviews of their BEV charging point installation service. Makes sense for a "greenwashing" service undertaken by a FF company to be low-priority.

Solution 1: Swap the 32A MCB for garage sockets for a 20A, and install a 16A BEV charging point (applying diversity). 16A is plenty for a PHEV, but if you see a big-battery BEV in your future then you'll only add 120miles (ish) in 8hrs overnight. Fine if you have a short commute, but you do a lot of miles and you get home late/leave early it's not going to cut it.

Solution 2: Install a 32A Zappi (or similar). This can vary the charge rate of the BEV to ensure the garage supply never goes above 32A. So if the car is plugged in and you run your lawnmower (or whatever) from the garage sockets, the car-charging will slow down while the device is running. Won't be a problem for your slow-charging BEV, but important if a friend/family member charges their BEV, or you get a BEV in future.

In all circumstances you need a proper spark to check over the installation.

BEV charging isn't the same as other devices. Your washing machine might be rated at 13A, but it only draws that momentarily (while heating water) the vast majority of its 2hr cycle it draws 1-2A. Whereas BEV charging draws full whack for the entire 10hr charging period.

2,320 Posts
On 14/10/21 I started with BG (HIVE) and still waiting on my chargepoint.

I have 2 electric showers only one used at any time. The fuses are 50A and 40A. I also have power in the garage and the usual cooker, washing machine etc. My circuit board fuse is 60A. They are now saying upgrading my house supply from 60 to 100A still won't be enough to be able to fit an EV point.

My next door neighbour has a bigger house and got his EV point from Podpoint in 7 weeks. I've been waiting 3 months.

Anyone any ideas how to get them to get their finger out? I'm terminally ill and that doesn't seem to bother them 馃槥
Bin off BG! They're crap. It is insane to have a FF company install a product designed to ensure they go out of business!

You shouldn't have 2x electric showers on a 60A supply. Installing one electric shower on a 60A supply OR an EV charging point is a bit iffy, and prohibited by some DNOs. Two of the above is negligent, three is utter silliness!

No one credible will install an EV charging point at your house without significant work.

Diversity is a complicated subject and certainly an electrician is permitted to exercise judgement. "Diversity" is why 2x 32A rings and 2x 6A lighting circuits (totalling 76A) can be on a 60A supply. Basically it means your washing machine probably won't be heating water at the same time as your toaster or kettle is running. The vast majority of devices pull their rated bower for only a few minutes in any hour and probably not at the same time.

There are several ways to calculate diversity and the rules allow plenty of judgement to be applied by the electrician. However no diversity can be applied to the first two electric showers, and never to a BEV charging point. That is why under no circumstances should 40A and 50A electric showers be on a 60A supply. They're too much even if there were no other circuits!

You can get a "priority board", this can be set up to switch your BEV charging point off while the shower is running and give power to whichever shower is turned on first shutting the other one off while the first is running. You cannot just say "we never use both showers at the same time" it is those situations that burn people's houses down!

Here is what I suggest:

Step 1: Upgrade your supply to 100A.

Step 2: Get a priority board installed for the two showers and a Zappi (or similar) BEV charging point, that can vary the charge-rate in real time to ensure you don't go over the 100A.

2,320 Posts
Thank you. Glad to have some help. Sadly only after looking on here have I discovered BG are no good. (Wish I looked earlier). They say they will eventually get it done. Surely there are homes operating even more electricity than me though?

Nobody tells you about EV pitfalls when you buy the car.

It was a qualified electrician that fitted the second shower. In all honesty we have never had 2 of them on at the same time.

Surely because we would only ever charge overnight there would be very little load issues?

BG say they will contact the DNO re the upgrade to 100A but we would need to disconnect one of the showers. Does that make sense?

They mentioned something called an isolation switch is that something that is useful. Sorry I'm not an expert in electrics so any help is great.
I believe you when you say you don't use both at the same time. But that is very different from fitting a device that prevents them form running at the same time. An electrician should have considered what happens if you move out, or on your daughter's wedding day when 4x bridesmaids all need showers, or whatever...

A priority board is a standard solution to this problem and one that your electrician should have fitted as standard with a 2nd electric shower irrelevant of 60, 80, or 100A supply.

However electric showers might pull a huuuuge amount of power, but they only do so for 15-30 mins a day. A BEV charging point can pull full power for 10-12hrs straight. That is a different scale of problem. But one easily solved with a Zappi (or similar load limiting charging point).

2,320 Posts
Thanks I understand now and thanks for the explanation(Luckily one son and he's flown the nest - no daughters馃槉).

I'm going to back to British Gas to say please fit a priority box and arrange the upgrade fuse to 100A and see what they say.

My DNO should upgrade the fuse for free but what would be a reasonable charge by BG for supplying and fitting the priority box etc. so I can check they are not going to rip me off?

Will keep you guys posted.

I know someone who was charged 拢135 by his DNO recently to have his supply upgraded to 100A. He was happy because he'd been lead to believe he was on a looped supply...
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