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A house will only need to load shed if the incoming supply is limited. Currently for most houses the incoming fuse comfortably covers all demands. It is rare that the 60+ amp fuse blows!
A protective device like a BS1361 HRC type fuse will require a very high current to blow, it's purpose is to protect your incoming supply cable and not your loads. It will take 100 amps no problems and the issue you need to address is overload current if you have to many circuits taken from your supply which can result in thermal events and not prospective fault current which will blow a fuse.
 
I am aware average domestic demand 1-3 KW per hour per household - depends on time of day and size of property etc. Adding a 7KW EV charger will not overload the house, but it would give the network a problem if they all come on at the same time.

There are ~30m households and ~30m cars in UK. Average mileage is 9000 pa (180 per week) - below the range of most EVs. Assume each EV needs charging once per week.

A typical EV does 3-4 miles per kWh. Weekly charging need is 45-60 kWh (2000-3000 kWh pa). An average household uses ~3800 kWh pa - thus EV charging adds ~60% to demand.

In 20 years as EVs become the norm, domestic network capacity will need to increase by ~60% - approx. 3% pa - feasible if addressed with commitment.

There has also been some debate over the number of charging points required to replace fuel pumps - in most respects this is a nonsense debate:
  • all ICE cars need to be refuelled at a forecourt
  • most EV charging will be at home, work, car parks, shopping malls, etc. Note 50% of properties are detached or semi probably with capability for home charging.
  • fast charging capability will be needed for those travelling long distances, or who have no other options. I would guess between 10 - 30% will need "forecourt" fast charging
  • on the basis that filling with petrol or diesel takes 5 minutes, and a 75% fast charge takes (say) an hour, the charger will be occupied for 20 times as long as a petrol pump.
  • the number of chargers required will be (say) 20% of EVs which need fast charging x 20 times as long - 4 times as many charging points as petrol/diesel pumps
  • EV charging points need network capacity - but otherwise limited investment.
  • Installation of charging points may represent a profit source - attracting folk to health clubs, hotels, theme parks, airport parking, theatres, concert venues etc etc.
All the above are guesstimates. Some folk may have have very skewed circumstances - living 30 miles from the nearest civilisation, two miles up a muddy track, towing horse boxes, travelling 40k pa etc etc. But note the average UK car commute is 10 miles.
 
It's time to use our coast line, why we don't have turbines in the Thames barrier always baffled me, lack of foresight perhaps, but then it was discussed at a pre-planning meeting and dismissed as too expensive, don't think that conclusion would be reached today.
 
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In 20 years as EVs become the norm, domestic network capacity will need to increase by ~60% - approx. 3% pa - feasible if addressed with commitment.
Except the actual process of increasing capacity is not a uniform, gradual one. It comes in discrete, disruptive chunks.

New generating capacity.

New pylons and HV cables to distribute it.

New substations or expansion of existing ones to accommodate more or larger transformers - where I live that will mean knocking down houses or compulsorily purchasing bits of gardens.

Digging up roads and pavements to beef up cables.
 
Individual projects will happen in chunks. But across the country it will seem a steady change:
  • priorities depend on current capacity, demand changes, availability of skilled resources etc
  • some will create disruption. Many will simply expand the scope of work already scheduled.
There may be several hundred major projects of varying complexity with start and completion dates spread evenly over the 20 year window - eg: new wind farms, power stations, grid upgrades etc.

They will create local disruption, but simple resource constraints and sourcing major bits of kit means it will not all happen as a "big bang".

The alternative is to not bother. The "its all too difficult" philosophy consigns the country to a sort of technological paralysis. We would still be cooking food over an open fire, the horse and cart would dominate transport, and air travel would literally be for the birds!
 
  • the number of chargers required will be (say) 20% of EVs which need fast charging x 20 times as long - 4 times as many charging points as petrol/diesel pumps
  • Installation of charging points may represent a profit source - attracting folk to health clubs, hotels, theme parks, airport parking, theatres, concert venues etc etc.

I would assume that overstaying at fast chargers will be greater than at a petrol pump. At the petrol pump you queue (sometimes) fill up, maybe pick up some bread and milk then pay.
At a fast charging station people will want to do something with those thirty minutes. If they are at the supermarket they are unlikely to be back that quickly, unless they just want bread and milk.

But the increase in number and hence space required by charging points is a bit of a red herring. Just looked at the Morrisons in Teignmouth on satellite view. They appear to have about 182 parking spaces (it is a bit difficult to count and I did not check) of which about 70 where next to the building or landscaped areas. No additional land would be required, or parking spaces lost, to install charging points in the landscaped area or fixed to the building for a third of the parking spaces.
 
Motorway services could be an issue, they would need to increase there capacity to accomodate many cars filling up for maybe thirty minutes rather than just five. Also they would have issues with available electrical infrastructure because when they were built EV's were not on the horizon. If as you say some supermarkets have large parking areas that are underused then it could be a case of diverting EV's to charging points installed here.

Looking further ahead there will become a point where maybe personal transport becomes history, just no way to make it efficient unless you can ensure full occupancy. What is more efficient, an electric bus carrying fifty people or twenty five cars each carrying two people?
 
Motorway services could be an issue, they would need to increase there capacity to accomodate many cars filling up for maybe thirty minutes rather than just five. Also they would have issues with available electrical infrastructure because when they were built EV's were not on the horizon. If as you say some supermarkets have large parking areas that are underused then it could be a case of diverting EV's to charging points installed here.

Looking further ahead there will become a point where maybe personal transport becomes history, just no way to make it efficient unless you can ensure full occupancy. What is more efficient, an electric bus carrying fifty people or twenty five cars each carrying two people?
Just had a look at Exeter services. There are about 500 spaces of which about 136 (27%) are next to landscaping or footpaths. There appear to be six chargers in a hatched off area which may be wider than normal bays which would effect the number of spaces available. I would assume that in the charging point was on the front or rear of a vehicle then normal width bays could be used but if the charge point was on the side it could be a problem.
 
What is more efficient, an electric bus carrying fifty people or twenty five cars each carrying two people?
The cars as the passengers go a - b unlike to bus users who have to go make arrangements to get from a - b wait ages then travel to c then make other arrangements to get to d
 
The cars as the passengers go a - b unlike to bus users who have to go make arrangements to get from a - b wait ages then travel to c then make other arrangements to get to d
That will be a problem for some but not for others.

If you are able bodied and not carrying lots of stuff*** and live close to the bus top it is easy to walk.
With GPS trackers in buses there would be no reason to wait for long as you would know how far away the bus was and how long it took you to walk to the bus stop.
at the other end you just get off the bus, no need to find somewhere to park and maybe pay 9and when you return your parking space is still there)

** I have taken 2.1m long roofing battens, office chairs and small tables on the bus.
 
Lots of reasons above why we need smaller cars. The first law of green energy is find ways to use less - sorry I have said this too many times
 
** I'll bet your fellow passengers loved you for that !
:)
They weren't at the same time! but I did get a few strange looks sat on the chair at the bus stop and in Exeter bus station. The office chair and small table did involve two changes of bus. I am currently sat on the chair and the table forms a utilitarian bedside table.

The office where I was working in Exeter did not want them, they filled up a skip with furniture they did not want. I put some out the back with notes on saying please help they want to put me in the skip, some items went some did not get saved.
 
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Looking further ahead there will become a point where maybe personal transport becomes history, just no way to make it efficient unless you can ensure full occupancy. What is more efficient, an electric bus carrying fifty people or twenty five cars each carrying two people?
I am not a bus user - but a general observation would be that they are rarely full outside of morning and evening rush hour.

Buses are inherently time inefficient - travellers need to get from origin to bus stop, from bus stop to destination, and are constrained by timetables.

When self driving cars become available buses will rapidly become obsolete - why haul around a 50 seater bus when only 15 seats are occupied.. Automated EVs will operate only when needed from origin to destination.
 
I am not a bus user - but a general observation would be that they are rarely full outside of morning and evening rush hour.

Buses are inherently time inefficient - travellers need to get from origin to bus stop, from bus stop to destination, and are constrained by timetables.

When self driving cars become available buses will rapidly become obsolete - why haul around a 50 seater bus when only 15 seats are occupied.. Automated EVs will operate only when needed from origin to destination.
Most cars have no people in them what so ever outside rush hour.

When I was working in London I could get from site to site quicker on the bus than the people I was supervising in their van. I did not have to look for a place to park which is inherently time inefficient. I could also work on the bus, phone people and make notes etc .
 
Buses are inherently time inefficient - travellers need to get from origin to bus stop, from bus stop to destination, and are constrained by timetables.
But they do not have to be, I can remember when Eastern national used to work with Marconi's so that buses would be waiting at various pickup points to collect workers from outlying towns and then bring them back at the end of the day. Trouble now is that we no longer have such huge employers on massive sites with a large workforce.

The issue with travel cannot be addressed as a collection of individual problems but must be taken as one big problem, one of the big ones is the daily commute. This is just bad news in so many ways, often single occupancy, this person traveling east to work passes many traveling west to work and then the vehicle sits parked all day doing nothing and this cannot be sustainable.

When self driving cars become available buses will rapidly become obsolete - why haul around a 50 seater bus when only 15 seats are occupied..

Coming at a problem from the wrong direction, when the cost of individual car ownership becomes so high then 50 seater buses will be cramed. Self drive, EV or whatever, single occupancy is wasteful and not cost effective. Maybe if no one owned a self driving EV and it was a borrow scheme then with the right system the vehicle would collect people going to the same destination so it was full, drop them off and go and do something else. The people would then do the opposite when they needed to get home.
 
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