If you had a tap at home which delivered fuel for your vehicle(s) overnight, how often would you need to visit a filling station?
Been there (not the overnight bit, but fuelling at home). For quite some time I was fuelling my thirsty V8 Land Rovers from red propane cylinders and a pump (I have both an electric and a hand pump) - legally paying the fuel duty on it before anyone comments on that.
As you point out, you can do a fair range without having to use a public filling station - and for a lot of use the same would be true of EVs, except for the substantially reduced range.
But I do think that the "forced take a break" scenario is never going to be popular with the majority of people who do have to use public filling stations. I see several different groups using them :
Those that cannot fill up at home because they only have on street parking, and cannot fill up at work because employers aren't going to invest in putting (possibly dozens, hundreds, or thousands
) of sockets all over the car park*. They will have to go to a charging station and it won't really be a needed break in what would otherwise be a short journey. Converting every lamp post would only make a small difference to this given the wide spacing of them along the streets. I'm now back in the "have the luxury of my own off-street parking" brigade again
Those that travel a lot - think salesmen, service technicians, etc. It's going to be hit and miss whether they can plug in at any destination and any enforced break is likely to be unwelcome.
People not in the above but taking longer trips. I can see there being a case for parking up and taking a break - but that only works now because there's so few EVs that the charger is probably available. Given the push for faster charging, that means some very large loads to cater for the "splash and dash" group - but unless everyone is very co-operative (ha
) then those staying for (say) an hour or more will end up pulling a large load and then tying up the charger for some time. I suppose there is scope for putting in a larger number of slower chargers in some places.
But none of that gets round the fundamental issue that regardless of how you redistribute the "fuelling" - we don't have (and don't have any prospect in the foreseeable future of having) a surplus of zero/low carbon lecky and EVs simply move the carbon burning from a portable engine to a centralised gas or coal burning power station.
* Where I used to work, there were probably several hundred parking spaces altogether and sometimes there were none at all left (leading to some "creative" parking at times). The landlord would not even spend the money needed to put magnetic holdbacks on the fire doors on our floor (the system interface was already in place for it as there were some downstairs) leading to a routine process fo removing all the wedges each time there was a fire safety inspection and the propped open doors were flagged up, and new wedges appearing within the next week or two to make the place habitable (only way to may the place tolerable in hot weather is to get through draft needing the fire doors open).
Chances of them shelling out for even a single charging place, on the low side of nil unless someone else paid for it. I can't see the government funding any meaningful widespread installations - and by meaningful I mean more than a token one or two dedicated spaces.
And if you installed (say) an 16A blue socket in front of every parking bay - what diversity factor would you apply to the wiring and protection ? How far ahead would you try and plan ? How would you deal with "theft" of lecky ? How would you charge people for using them ?
I guess that "eventually" someone will come up with a scheme for interconnected slow chargers that will co-operate amongst themselves to control total power draw, and have some way of the user "logging in" so they can be charged for the power. That would ease the diversity calculation since you'd just rely on a group of (say) 20 chargers restricting their total draw to (say) 60A - running off a 63A single phase supply. The problem then is that the users won't know if they'll get 3A (750W) because all the bays are in use, or 20A (5kW) because most of the bays aren't charging. But looking at the building where I used to work - the main fuses for the supplies were only 300A/phase (there were two such supplies). Allow 60A/20 parking spaces and that's 1/3 of the supply capacity taken for 200 parking spaces with potentially only a very slow trickle charge. Allow sensible charging rates for everyone and you quickly get to a situation where there's no supply capacity left for the building itself. I could seriously see mass charging being restricted to as little as (say) 1/2kW or less if there were truly mass adoption of EVs.
I know that most of my colleagues (and myself for a while) did not have off-street parking, many being on streets where it was good luck if you got to park vaguely near your own house. So charging at work would become the norm for them - so it's not good enough to be able to get enough to "just" cover your trip from home to work.
