Skip to content

Electric cars do require an entire societal redesign

Electric car owners have been warned that if they attempt to boil a kettle while charging their car it will blow the fuse.

The National Grid expressed concerns that an average size 3.5kW battery charger would take 19 hours to fully charge a car battery, even when it is 25 per cent full.

A “thought piece” document obtained by the Financial Times warned that a more powerful 11kW device would still take six hours to charge a car battery and during that time, the use of everyday items such as kettles and ovens would blow the fuse.

“The average household is supplied with single phase electricity and is fitted with a main fuse of 60-80 amps,” the National Grid said.

“If one were to use an above average power charger, say 11kW, this would require 48 amps. When using such a charger it would mean that you could not use other high demand electrical items…  without tripping the house’s main fuse.”

The expense of the changes should be added to the costs of electric cars of course…’s not at all obvious that they therefore are cheaper that petrol, even when emissions are taken into account.

39 thoughts on “Electric cars do require an entire societal redesign”

  1. I don’t want an electric car and while relatively young I won’t live to see them get forced upon us. I have children unfortunately so I won’t even be able to die smug and happy in the knowledge that the stupid millennial cunts who are driving this idiocy will starve to death because of it, if they aren’t beheaded first. I would happily row off to meet my maker on a sea of their tears if only I hadn’t foolishly impregnated my wife.

    God, I’m depressed – and I have a great life 🙂

  2. My caravan mains battery charger automatically inversely varies it;s maximum charge rate to current usage elsewhere.

    Provide current usage feedback into car charger, kettle and car charger can both be on on at the same time.

  3. Tim, it’s not at all obvious that they therefore are cheaper than petrol. Can I rephrase that for you ?

    it’s not at all obvious that they therefore are cheaper than petrol, once the illogical tax authorities (whose ONLY interest is gouging) get their mitts onto them.

  4. We pick up our EV tomorrow (Tesla Model X); had a charger installed the other day and it wasn’t a big effort. The charger can handle 3 phase 60amps each phase but we only have single phase in the house. Electrician has limited it to a max of 48 amps given the state of our wiring and to avoid it overloading when everything comes on. We are planning on rewiring when we do so renovation work in a couple of years time so may put three phase in then.
    Cost of the charger installation came to NZ$400 – so about a month’s worth of petrol.

  5. James in NZ;

    List price for that is $145,200, base model, climbing to well north of $200k. As you correctly state, the cost of the charger is not a significant addition to your bill.

  6. “without tripping the house’s main fuse”

    As it’s the supplier’s fuse, a great fat cartridge fuse, with the supplier’s seal on the cover, “tripping” means it’s blown and you can’t change it yourself – so you’ll have to wait till they send someone to replace it.

    But that’s still good, ‘coz you’ll be “saving the planet”

  7. I think the point that Tim was making was that the average house hold would eventually need to have an upgrade to the actually electricity supply, not just minor adjustments to the wiring and fuses of the house.

    Think about it. An 11kw charger is just for one car. If you have a two car household (as most households are these days), then you either have to take turns charging up the cars (perhaps this could be done automatically with a switching system or an alarm clock to wake you up in the night to change the cable over to the second car) or you would need 2 11kw chargers.

    So the real question is how much would it cost for you to have the electricity supply to your house upgraded? In effect, you would be moving from a domestic supply to a light industrial supply.

  8. Bloke in North Dorset


    Most houses have a lower rated ELCB which is designed to trip before the main fuse to avoid that problem. Wel at least all mine have.

  9. @salamander: I remember reading somewhere that the cables in the street and the local distribution transformer are sized on the basis that the average current consumption of a house is around 13A or 3kW. Obviously we do not all turn our toasters and kettles on at the same time.

    Millions of chargers are going to invalidate this assumption. Who is going to pay for the complete rewiring of the country by 2040? Let alone the extra 30GW of new power stations required. I think it is hilarious; fortunately I will be too old to care by then.

  10. Bloke In North Dorset:

    The function of an ELCB (Earth Leakage Circuit Breaker) is to trip when the current in the live wire is not in close balance with the current in the neutral wire.

    It’s a safety device, not a current-limiting device.

  11. Tim is on to something here, and there are a few obvious worries:

    1) The cost of fitting fast chargers in sufficient places and sufficient numbers will be astounding. How do you handle the tens of thousands of streets with on-street parking?

    2) The problem of range still has not been dealt with, and isn’t there an issue with batteries losing their charge in the winter, which, while relatively mild, can occasional produce some cold days?

    3) It is easy to imagine if not rural depopulation then certainly a decline in rural populations as the cost and difficulty of getting about increases.

    4) On the other hand, plenty of nearly new 3 litre German wanker wagons coming on to the market soon…very cheap.

  12. It takes at best 6 hours to charge batteries enough to give you a practical range of 80 miles. That’s going to sell?

  13. So, the National Grid reckons it takes 90kWh to drive a car 300 miles; therefore 300Wh/mile. In GB 2014, cars (not vans, lorries, buses etc) travelled 244.4 billion vehicle miles. If all of that were done by electric cars, it would require 73.2 TWh, or a continuous generating effect of 8.36 GW.

    In 2016, households took delivery of 108TWh from the grid (out of a total generated and delivered 336TWh). So we are looking at increasing the amount of electricity delivered to households by 70% by 2040.

    There are about 26 million cars so they average 9,400 miles p.a., which would require 2,820 kWh. At say 15p that gives a consumer cost of £423 per car p.a. or 4.5p per mile, which is not too bad.

    (But as Alan D says above, that’s before HMRC gets seriously involved.)

    What is really interesting is how long it will take to charge up a battery with 90kWh. The voltage in car batteries (for propulsion) is 400V so we are looking at 225Ah. At 48 amps it would therefore theoretically take just under five hours (so six hours is probably a bit optimistic in practice, given transmission losses etc).

    But suppose we want to charge up in 15 mins (it takes less than 5 mins to fill up a petrol tank). Then we need a cable that can handle 1000 amps (and a battery and connectors etc that can handle that sort of current). Quite apart from anything else, the cable would need to have a cross section of about 800 mm2, so it would weigh (if copper) about 7kg/metre (and that’s just the current-carrying component – imagine the sort of protection that would be needed around it).

    There is a lot of thinking that will have to go into this electric car idea before it becomes practical…

  14. Sorry, wasn’t thinking there – a 48amp domestic charger is charging at 240V so it will (theoretically) take just under 8 hours to charge our 90kWh battery, but I believe the National Grid was thinking the battery would still have 25% charge when we started (hence the six hours charging time). So we are not concerned at all about transmission losses etc in this scenario. Hmmm….

  15. Not to mention the enormous loss of revenue from petrol excise.

    That will need to be added somewhere else.

  16. @AGN:

    > ( that’s before HMRC gets seriously involved.)

    If HMRC are going to get involved, will we have to have separate meters for domestic electricity (cooking and lighting, etc) and car charging? Will the charger send a notification to HMRC so that Hector the Inspector can debit your bank account?

    Will it become illegal to use unapproved chargers to bypass the tax? I can see a black market developing here.

    For added hilarity, what happens when thousand of cars per day run out of charge on key motorways? This will cause the motorway system to clog up. Even better, what happens on cold, frosty, foggy days when the batteries can’t hold so much charge? Will there be tow trucks stationed every few miles on motorways?

    The more I think about it, the more bizarre the whole scheme appears.

  17. Bloke in Essex ( where the bright people come from) gets it. It’s not what any individual virtue signalling wanker does with his choice of vehicular penis extension. The country’s electicity production/transmission infrastructure wasn’t designed to accommodate charging electric cars. Any country. They can’t move out of a niche market. There isn’t the spare capacity there for them. To power an electric vehicle fleet would involve upgrading everything from the generating stations to the wiring in your houses.

  18. Obviously, you leave one battery charging back at home while you’re out driving with your second battery. Provided you can swap batteries in less than 5 minutes, it’s faster than filling up a tank of petrol.

    None of this solves the domestic electricity distribution problem though, so I guess we won’t be able to charge at home at all. We’ll have to go to commercial battery stations to swap our depleted batteries for charged ones. A bit like having to go to a commercial petrol station to fill up a tank of petrol. (How many people fill up their petrol tanks from their personal reservoir at home?)

  19. The market seems to be belatedly recognising all of this. Hence the growth in plug-in hybrids.

    In practice a PHEV offers all the virtue-signalling goodness of an electric car, without any of the practical shortcomings.

  20. @ Minke

    You’re right, I’m sure swapping batteries will be just like popping a new battery in my digital camera (I keep a spare charging while I am using the other).


    You’re talking about something that weighs hundreds of Kilograms…

    Sure, I’ve seen YouTube videos of ‘automated’ replacement centres where batteries can be swapped quickly but that would require every car manufacturer to standardise on battery design and fitment…

  21. >How many people fill up their petrol tanks from their personal reservoir at home?

    Ahem, red diesel …

  22. Swapping batteries, sounds like it would easier to just change horses at the next inn on the highway. At least there would be buxom wenches’, flagons of ale and pies.

  23. It’s simple. We can increase the driving range by putting solar panels on the car roof.

    Due to the low angle of the sun, fitting them upright (or at an angle to the sun) would be better than flat on the roof. That way they can be extended upwards quite a bit (subject to bridges) and hence produce even more power.

    If they could be designed without any wind resistance, then it should be feasible to have them continually change angle to be always facing the sun (or moon)…

    Interested, if you’re heading for the Outer Hebrides (or was that a different thread), you’ll be required to install a windmill (on the vehicle of course).

    OK, that’s it – get me out of here Scotty.

  24. @Minke, BiC

    Yep, they weight a lot. Also, the entire pack is generally placed in the floor pan, so is something like 1.5~2m long and 0.75~1m wide. Swapping them out is somewhat non-trivial.

    Last time I looked, Tesla offered lifetime guarantees on the battery pack, such that the range of the car would remain stable. What they would do, is replace the battery once the capacity had dropped off (call it down to 80%) over the charging cycles. Musk/Tesla’s home storage battery packs are basically those swapped out from their cars, on the assumption that the demands on the capacity and charging cycles are different. Also, the battery tech can’t be mechanically recharged.

    FWIW, a guy I know bought a Tesla, and the super turbo nutter charger (actually two, one at home and one at the office). He didn’t really need either, but discovered that it is a new, separate supply, and Tesla would basically eat the installation cost. Particularly if you let them put the location on their maps, which also means they cover some of the electricity cost.

  25. Yes, and hand-held torches and portable radios will never take off as it would require manufacturers to standardise on battery design.

  26. We looked into rewiring recently, our electrics are rather old and to be honest if we ever sell it will do better with decent plug system and modern electrics.
    11kw can be handled well enough once upgraded, would be more of a problem with 1970s electrics.
    Been looking at the Leaf, 6.6 charger seems reasonable. Car is outside the house over 12 hours a day anyway and will only need a couple of charges a month.

  27. Yes, and hand-held torches and portable radios will never take off as it would require manufacturers to standardise on battery design.

    Well yes…

    But even though the D-Cell was introduced in 1898 and the AA in 1907 (so says Wiki) I still need a store of a wide range of different batteries to keep the house going – AA, AAA, PP3, various ‘CR’ sizes, etc…

    It is hard to see how a ‘standard’ one-size fits all battery could be suitable for every type of vehicle…

  28. I’ve been working on the assumption that Electric cars are why HMRC are so interested in per mile charging and the push for Galileo and in car black boxes

  29. Sorry kids, no hot food tonight because daddy is a stupid virtue signalling twat who bought an electric car and has to charge it all night. No TV or PlayStation either – read this book instead. With this pocket torch.

  30. PF

    ‘Interested, if you’re heading for the Outer Hebrides (or was that a different thread), you’ll be required to install a windmill (on the vehicle of course).’

    Because I’m having a lazy day today I did actually google houses up there. Bit small and it looks cold. But Guernsey looks a better bet – not to mention, I can look out for Arnald.

  31. Given that people do not notice a sequence of very small changes, is it possible that the Greens can realise their insane dream of deindustrialisation by two decades of tiny, tiny degradations, backed up by intense public disapproval of criticism, even criminal sanction?

  32. Re: David Moore

    List price for that is $145,200, base model, climbing to well north of $200k. As you correctly state, the cost of the charger is not a significant addition to your bill.

    We’ve gone with the cheaper model – so about the same price as an X5 or Range Rover Sport. Definitely not a cheap car (for that sort of EV you are looking at a $10-15k second hand Jap import Nissan Leaf); but not out of whack for what you get in the petrol world for something with similar spec.

    The thing with electricity supply and battery changes etc is that 95% of the time you will charge up at home, and overnight. Most EVs have timing systems built in so that you can set when you want the car to charge up (my electricity company offers an extra 20% discount on its overnight rates for EV owners … so I’ll set it to charge from 11pm to 7am). If you have two Teslas then they will also communicate with each other to share power draw (so instead of both charging at full tilt, one will do so to 80% and then the other).

    There will be infrastructure requirements and issues for when you need to travel (although this is currently being solved by the market – many of the petrol stations on main routes have fast chargers now); but this isn’t a biggie with decent sized batteries.

    The big issue for places like the UK is how do you deal with city dwellers who don’t have off-street parking. This will have infrastructure supply issues as you need to figure out ways to charge those cars without dragging cables across the street; but then city dwellers don’t drive long distances so will probably only need to charge once a week or so.

    Obviously the other issue is taxation and funding roads. In New Zealand we have a system of Road User Charges for vehicles that are fueled by fuels that aren’t taxed at source (effectively diesel at the moment). You buy these in 1,000s of KMs at a cost of $62 per 1000 kms and get a “licence” that you stick on the windscreen (my parents generally get 10,000 kms at a time which sorts them out for a year). Every now and again the police will check when they do a roadside check; and it gets checked when your car gets its WOF (NZ’s MOT). Satellite tracking would be better but is probably harder on a privacy front and I’m not sure if cost/benefit would work out.

    Pretty much the only “subsidy” that EVs get here is an exemption from RUCs until the make up 2% of the vehicle fleet. But everyone who buys them now knows that at some point they will be taxed to fund the roads etc so it shouldn’t be a surprise when RUCs are implemented for EVs.

  33. Couple of points (I own a plug-in hybrid):

    @Minke – second battery: the majority of the value in a pure electric vehicle (like a Tesla or a Leaf) is in the battery. Having a spare that could be charged ‘offline’ is an expensive proposition. This is also why battery swapping at an electric filling station won’t work (even if the myriad physical issues could be addressed). How happy will anyone be to swap the nearly new battery in their shiny new electric Beemer for one from a 10-year-old Nissan?

    @AGN – charging time: the battery management system in an EV won’t let the charge level drop below 15% as this can have a very deleterious effect on Li-ion cells (so when the ‘fuel gauge’ shows “empty”, it really isn’t). Similarly, fast chargers (like your 12kW example) won’t take the battery beyond about 80%. This is because as the battery becomes fully charged its effective internal resistance increases and most of that 12kW is going to come out as heat, wasteful and bad for the battery. So the clever electronics controlling the charger will trickle charge at a much lower rate to get the battery up to 100%.

    As an example, my car has a 12kWh battery. When it shows ’empty’ (and the car switches to the petrol engine) it’s actually got about 2kWh left. If I recharge it from a domestic 13A socket, after 3 hours there’s about 10kWh in the battery. It takes a further two hours plus to get up to 12kWh. How long this process takes for a Tesla with 100kWh is left as an exercise for the reader.

  34. Blokes in North Dorset & Essex,

    Do they still burn witches in North Dorset & Essex? I ask because I’d never even heard of ELCBs until this morning, let alone looked close enough at the gubbins to realise that I owned one, so it was a bit of a shock to hear a loud click during an electrical storm this evening, followed immediately by delucidation. The choice between sitting in darkness or going to the pub and drinking beer has only one outcome: damn you and your spells!

  35. The windwank/piddle power capers the ecofreaks advocate and steal our cash for won’t be able to run large numbers of electric cars.

    The whole Greenfreak circus needs to be smashed up.

  36. All these comments – and yes, thanks Bloke in Essex for pointing out the inherent assumptions in the local power distribution network (though I believe the After Diversity Power Demand is assumed to be 2kW/house).
    So the local infrastructure is designed on the assumption that the majority of house, when averaged out, won’t pull more than about 8A. Depending on the size of the street, number of homes served, size of substation, etc, the fuses at the substation end might be as small as 300A (or as big as 800A).
    So potentially, it takes just 6 houses/phase to fully utilise the 300A available when they plug in their hybrids to charge. Hmm …

    But what none of these eco-wankers want to talk about is where the lecky comes from. The nearest they will ever get is to talk about the entirely fictional case where paying more for a green tariff makes any difference at all. And the reason they won’t talk about it (at least those that understand that magic unicorns are about as real as green tariffs) is because in this country, when you add some load to the grid, except for a few short periods of very low demand, in summer, when the wind is blowing “just right”, and the sun is out, then that extra load is supplied by burning coal or gas. So really, switching from petrol or diesel to an electric car is switching to coal or gas power – just with a lot of efficiency losing conversion between fuel and road.

    Yes, plug in EVs are gas & coal powered ! Before they are plugged in, there is no “spare” green power – so plugging them causes enough extra gas or coal to be burned to supply the load they take. Now, when we’ve built another 20 or 30 GW of nuclear plant, that might change – looks out of window, no I don’t see the Porcine Aerobatics team out today.

Leave a Reply

Your email address will not be published. Required fields are marked *