Dieselgate

But huge numbers would be charged at work during the day - so that people could drive home again. Or, if they are close enough to do out and back without recharging, so they can arrive home with enough charge in case of unexpected need - child phoning up needing a lift; things needed from the shops; a call from friends to go out for the evening, etc.

Looking out at my street tonight Chris we have two people without a car (both pensioners ) the rest of us apart from my next door neighbour who has one have at least two cars , several have three some have four.

People will plug the car in as soon as they arrive home from work, peak time for domestic electrical use is 4.30 pm until 11 pm with a heavy spike between 5.30 and 9.00 pm .

We don't have the cable capacity to tap out another 20KW per house (the average house has 2 cars now)

Basic fact we just do not have the capacity with current infrastructure to charge vehicles at home, most families now have 2 cars, some more Domestic service cabling was never designed to carry high sustained loads many properties are only serviced by 16mm or 25mm cable, realistically if your going to charge vehicles your minimally going to need 35mm possibly 50 or 70mm for future proofing unless we start talking three phase

The voltage will need to be bumped up to keep the amount of metal required sane. So yes, three phase.

I think charge points should be 13A - 8 hours for a full charge?

Well, as I see it, charging would simply have to happen overnight, and peak grid time charging would have to be lower rate, trickle charging. If households can't manage on 2 full charges (say 200 winter miles a week?) then it's a sorry state of affairs.

All of these 'what if' scenarios are simply defeating the point of the exercise even further. People should drive less, shop (and work if they can) local, car share, use public transport, cycle/walk and so on.

There, i've had my say :-)

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I've not looked up the statistics, but I would imagine that it would not need 10kW for 8 hours to charge a car that may only have used perhaps 25% capacity. Charging will be smart; presumably a form of taper charging such that the full demand will not be required for the whole charging period.

Long before this is an issue, 99% of homes will have smart metering. The first versions already installed in business premises transmit data once per day. The 'mark 2' rollout will send data every five minutes (unless you opt out). This means loading in a particular area will be available in near-real time. It would not be difficult to split the load between house and car (as is done already for some forms of electrical heating) so that charging uses surplus capacity.

Chris

Nissan know the 24KWh battery pack was a bit limiting and now have

30KWh, 110 mile range.

Chevy Bolt or Tesla 3 will have 200 mile range.

How many people do you think drive 50 miles to work and back home EVERY day?

40 miles each way is about the limit for most people to drive to work. A 30KWh Nissan Leaf will do that without a recharge and have a trip to a shop to spare. 40 miles will take about 1 hour each way + 7 1/2 hour working day + 1/2 hour lunch = 10 hours. So if they take the kids to school for 9am, they would get to work at 10am, finish at 6pm, home for 7pm and will NOT be collecting the kids from school. If they have to collect the kids from school at 4pm then they have to start from home at 6am. If they don't work for a firm that allows start between 7am and 10am but has fixed working hours then they won't be taking or collecting the kids from school.

Google directions for Cambridge to London 65 miles. Google says M11 is 2 hours without traffic, train you have choice 1 hours 7 min or 1 1/2 hours. Only a nutter would drive it every day.

Furthest any of my colleagues does is Grantham to Derby. 46 miles, 1 hour 20 min by car, 1 hour 11 min by rail + 5 miles bus then works inter-site bus. He starts at 7am and finishes at 3:30pm to miss the peak traffic.

If you can run a cooker or a shower you can run a cable to a 32A charger.

2 cars 8 hours each. (you will overrun Economy 7) 1 car 4 hours.

But electric cars are clever like a 40 year old Economy 7 storage heater. They don't draw power the instant they are plugged in. They can be told what time to start and stop charging at.

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The Nissan leaf seems to be the most sensible vehicle to consider. (By the time electric vehicles are mainstream (if they ever are), their efficiencies are likely to be much higher.)

There are various versions, and they all have options for charging.

Some need a 30A supply to recharge fully in 8 hours, so 4mm2 might be suitable.

Others need a 40A supply to recharge fully in 4 hours, so 6mm2 perhaps.

They all have an option to recharge from a standard 230v socket drawing 10A, and taking 12 hours.

Where on earth did you get sizes such as you have quoted?

Chris

A very good question. And one that will be raised in the house when the lights do start dimming thats when we have to many windy mills and a high pressure system in the wrong place.

Roll on the day of the suitcase nuclear portable generator//

One day....

I got 'augmentation' to three phase for my home workshop, thirty years ago it cost about 350 quid, which was a bargain considering the labour, equipment, men and vehicles involved.

Very few houses in the UK actually have a three phase supply though

I found that regular 10kw through the 100 amp fuse that feeds the house eventually cooked the connectors on the fuse, I had to knoock it out with a plastic hammer! , cleaned it up and transferred the house to a different phase. Maybe when they install a new meter next time I will get a new fuse head unit. (any idea what the 'proper ' name is for the boards fuse unit?)

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Local distribution is via 3-phase supply, with each house connected to one of the phases. That's why in a power cut situation, your neighbours each side may well still have their supply.

It would be pretty easy in most cases to cable from the street, and I know that this has been done for folk with 'enthusiast grade' equipment in their domestic garage.

I don't believe that will be needed in the context of electric vehicles however.

Chris

More like 6mm2 per charging point possibly 10mm2 depending on run

Probably 10mm2 possibly 16mm2 per charging point again depending on run

Which is pointless unless the vehicle is only used occasionally

Quoting sizes for main service supply cable underground supplying the whole property based on 150Amp supply 25 meter run of cable from distribution meter board to the main service supply in the road plus a bit of future proofing , also worked on two vehicles and allowed for charging during peak periods which is likely to happen As battery and charging tech improves you will need larger supplies to. Not the cable sizes to the equipment.

The option would be to switch to three phase cabling

The issue Chris is network and cable capacity all the electricity comes from one network , the cables that supply the service to our homes are just not large enough in the majority of properties , that's before you get into the main underground distribution cabling between power station, substations and the local networks . Many substations are at capacity now, ours was replaced about 8 years ago, every time you had a popular sporting event on TV or a real cold spell the station would go down and i live in Birmingham.

My incoming cable is 16mm2 installed 1933 ,the majority of properties in Birmingham have similar sized installations if built prior to the

1960's .

If we run our shower cooker and oven at the same time our lights dim, our original fuse was 40 amp , it was upgraded to 100 amp about 2 years ago but we are on the limit , without a cable upgrade which would cost about £2K that's it

Not that simple your board will have a limit , you certainly would struggle running a 10KW shower an electric cooker, hob unit and charger unit requiring 32 amp supply at the same time on the majority of UK homes the supply was not designed for that level of sustained loading it will overheat

That's rather like saying my BMW does 45 mpg. It can under some circumstances. but the overall MPG for say a year is very very different. And given car makers always give the best possible scenario, it would be good to know what that 200 mile range comes down to with normal use. Heating on in the winter, for example.

I'd be willing to bet that heating an electric car to the same level as you would with a petrol one on a cold winters day would half the range in town use. Maybe even more. What many don't realise is that a car heater can deliver the equivalent of 5 kW of heat if needed. And of course the batteries won't perform as well when cold either.

They've been saying that for more years than I can remember. Batteries are still the major problem, despite many billions having been spent on research. Lithium types are very expensive and have a short life unless cosseted.