Smart meters, electric vehicle charging points and Economy 7

[Avocet]

Hi all,

We live in a house built in 1995. It has a traditional Economy 7 single phase supply, with the day and night meters in a meter cupboard on an outside wall of the house. Current electricity supplier is British Gas.

I'm thinking of getting an electric vehicle charger installed - probably a 7 kW one.

The existing consumer units inside the house, have RCD circuit breakers in them. The "night" consumer using has two spare slots in it. The "day" one is full, but two of the slots are taken up with a doorbell transformer for a doorbell we no longer use.

I'm wondering about whether I should get a smart meter? If I do, what happens with the day and night consumer units in the house? Do I have to lose one of them or get two new consumer units?

Also, was thinking of asking for the Electric Vehicle charger to be connected to the "night" consumer unit, but does anyone know if they work that way, or are they connected after the meter but before the consumer units?

One last note. British Gas (my current electricity supplier) seems to have no smart meters anyway. The website says I'll just get put on the waiting list, but rather unhelpfully, doesn't tell me when!

 

[Old Salt]

I dont know about your economy 7 tariff and smart meter, but the EV charger will come off a consumer unit. Mine has a separate circuit purely for the EV charger. The smart meter can monitor your consumption in half hourly segments so presumably replace the “night” rate consumer unit.
Not sure what happens with Economy 7.

 

[Avocet]

I dont know about your economy 7 tariff and smart meter, but the EV charger will come off a consumer unit. Mine has a separate circuit purely for the EV charger. The smart meter can monitor your consumption in half hourly segments so presumably replace the “night” rate consumer unit.
Not sure what happens with Economy 7.

Thanks for that. At least it's one piece of the jigsaw!

 

[ericmark]

Economy 7 is a tariff not a system. It has changed over the years, it started with a white meter and anything connected to the white meter only worked for 7 hours over night, in the main it used a second fuse box, it was well before we got 30 mA RCD's.

But over the years it has changed, the idea was you could run washing machines etc, over night if you are brave and don't read all the cases of washing machine fires, but it also allowed a boost so you could use the storage heaters in the day, and we also got Economy 10.

Even the old white meter would be good for car charging, but there is more involved, the EV charging point with a non TN-C-S supply is great, but most supplies are TN-C-S so some method has to be used to ensure the earth is isolated with a car being charged out side should there be a loss of the PEN technical bit here but it means most chargers will lock out if they loose power, and need resetting.

What the government wants is for if there is a high demand the DNO (supplier of electric) can switch of electric car chargers so to maintain essential services, and to get the grants you have to do as they say.

However there is nothing to stop you having a 32 amp socket fitted for general use, for example running a welding set, and plugging the EV charging lead into that, this lead plugs into any 32 amp socket OK not cheap at £280 but this lead will plug into any 32 amp outlet, maybe not safely, but can be done, and would be safe in an integral garage.

If you have the proper EV charging point it should protect for loss of PEN even when the car is charged outside, and if you tell the electrician the 32 amp socket is wanted for your electric car, he would need to ensure it had all safety features, and he needs to have gone on courses to teach him the safe way to claim the government assistance.

But I would be interested to learn if an EV charging point would work on a white meter? I would thing you would need to press some reset button and some unearthly hour.

So wait and see what others say.

 

[flameport]

EV charge points (more correctly EVSEs) require a permanent mains supply, so connecting to an E7 or similar switched supply is not an option.
They have their own circuit which connects to your consumer unit just like any other circuit. If your consumer unit is old / obsolete / full, then a second consumer can be installed just for the EVSE, or the whole thing can be replaced with a larger consumer unit.

7kW is the normal choice, unless you have a 3 phase supply or inexplicably want a 3.5kW one which will take twice as long to charge anything.

It's possible to charge a vehicle using the cheaper overnight rate from an E7 supply, but that requires that the whole house switches to that lower rate, rather than just certain circuits.
Some are configured like that, others are not. If you have 2 separate meters, only the switched E7 circuits are on the cheaper rate so that is of no use.

E7 and it's variants are all at the end of their lifespan, and are already being replaced with alternatives provided via smart meters.

British Gas (my current electricity supplier) seems to have no smart meters anyway.

More a case of them not having anyone to install them.
Other, much better suppliers are available.

 

[SUNRAY]

Get one of these

as Eric suggests and get two 32A sockets fitted, one on each consumer unit so you can take advantage of the cheaprate but still charge during the day when required.

 

[JohnW2]

But over the years it has changed, the idea was you could run washing machines etc, over night if you are brave and don't read all the cases of washing machine fires ...

That's often said, and I personally would not usually have a washing machine (and certainly not a tumble dryer) running whilst I was asleep.

However, I wonder how rational such a thought process actually is. Intuitively ('common sense'?), I would have expected storage heaters to be far more likely to start a fire than a washing machine, but it doesn't seem that one is regarded as being "brave" by having storage heaters ('storing' at very high temperatures) whilst one is asleep

Kind Regards, John

 

[Avocet]

EV charge points (more correctly EVSEs) require a permanent mains supply, so connecting to an E7 or similar switched supply is not an option.
They have their own circuit which connects to your consumer unit just like any other circuit. If your consumer unit is old / obsolete / full, then a second consumer can be installed just for the EVSE, or the whole thing can be replaced with a larger consumer unit.

7kW is the normal choice, unless you have a 3 phase supply or inexplicably want a 3.5kW one which will take twice as long to charge anything.

It's possible to charge a vehicle using the cheaper overnight rate from an E7 supply, but that requires that the whole house switches to that lower rate, rather than just certain circuits.
Some are configured like that, others are not. If you have 2 separate meters, only the switched E7 circuits are on the cheaper rate so that is of no use.

E7 and it's variants are all at the end of their lifespan, and are already being replaced with alternatives provided via smart meters.


More a case of them not having anyone to install them.
Other, much better suppliers are available.

Thanks for that. I think the whole house swaps to the cheap rate at night. The reason I think this, is because the only things in the house that are connected to the "night" meter are the three storage heaters, which are off in the summer, but the night meter reading continues to go up.

Here are the consumer units:

And here is the meter. It's one meter with two dials in it.

Can anyone who understands such things, tell me what I've got, please?

 

[Avocet]

More a case of them not having anyone to install them.
Other, much better suppliers are available.

Oh, and that was the other thing! Would you be able to recommend any, please? Kia seem to work with two charger installers - PodPoint and BP. I spoke to a girl at PodPoint today, but she didn't fill me with confidence!

 

[SUNRAY]

You are correct, all your energy switches to nightrate so that simplifies things. Originally I read your post to say you had 2 individual meters which would have complicated things.

 

[winston1]

I'm wondering about whether I should get a smart meter? Don’t. They are for the benefit of the suppliers not you. They are not free. We all pay for them through higher bills.

 

[Avocet]

You are correct, all your energy switches to nightrate so that simplifies things. Originally I read your post to say you had 2 individual meters which would have complicated things.

Sorry! By "meters", I meant the two separate rows of digits for the day and night consumption, but I see what you mean, they're in one "box"!
One interesting thing that I can't get my head round, though. The storage heaters will only warm up at night (if we use them). So if the whole house switches to E7 at night, what prevents the storage heaters from drawing power during the day as well? Their consumer unit must be on some feed that only goes live at night?

 

[Harry Bloomfield]

More a case of them not having anyone to install them.
Other, much better suppliers are available.

Right or wrong - What BG told me, was that it was a desperate shortage of meters, due to the world wide electronic components shortage.

 

[ericmark]

Never had Economy 7, but am under the impression there is a forth wire which tells the storage heater when to turn on with modern systems, and turning to boost over rides this command to the storage heater.

As to the lead I showed, if being charged in a garage no problem using the lead in a 32 amp socket, the problem is charging outside, be it a hot tub or an electric car inside no problem with TN-C-S but outside there is.

 

[Avocet]

Never had Economy 7, but am under the impression there is a forth wire which tells the storage heater when to turn on with modern systems, and turning to boost over rides this command to the storage heater.

As to the lead I showed, if being charged in a garage no problem using the lead in a 32 amp socket, the problem is charging outside, be it a hot tub or an electric car inside no problem with TN-C-S but outside there is.

No, it won't fit in the garage. My much-loved old ICE car lives in there! The EV (if it happens at all!) will be a company car, so it can jolly well live outside! I might, however, build it a car port, as that's something I've been thinking of doing for the last 20 years anyway!