The National Grid state that there is not an issue whatsoever
It's not really National Grid's business is it?
The grid infrastructure that will need modifying is not going to be transmission assets.
, some local small cables may need replacing as part of planned renewals
Local small cables are where the grid infrastructure costs are.
Transmission costs essentially nothing, the distribution system is the problem, and planned renewals is not going to cut it.
A rapid transition to electric cars could easily add 30GW of grid demand in a decade or less, this is not demand growth we have seen since before the oil crisis.
This is combined with the necessity of withdrawing domestic gas use for heating and cooking.
(And this is before we consider Jevons paradox causing car use to explode as a result of the really low cost per mile of an electric car)
We could be looking at a doubling of electricity consumption in under 20 years, this will require enormous expenditure, just as it did before the 70s.
and that batteries & smart grid / charging will reduce the total generation capacity needed,
Outside of niche applications batteries are not going to make a significant impact on the energy supply, since the primary energy demand swing in the UK in a decarbonised system will be seasonal in nature.
And using a battery for one charge a year is going to get astronomically expensive, even before we consider self discharge concerns.
And we can't practically use electric cars for grid support without enormous cost and enormous losses from passing power through the LV system multiple times - which we reallly want to prevent.
What is this insane need to charge / fill at xx Mw/hr?
I as referring to the statements regarding the number of charging points exceeding the number of petrol stations as if this means EVs are rapidly taking over the world.
They are not.
You have to compare apples to apples.
Saying I have more charging points than petrol stations is meaningless when petrol stations have aggregate charging power orders of magnitude higher.
I top up the charge of my car at night, in car parks or off the solar here & there, when doing something better with my time and not having to waste my life at stinky dirty fuel pumps! Trains will do the same, at night, in layovers etc and will use much less power due to regen raking / power storage.
If everyone charges their cars at night, peak time will shift to the night and the price of nighttime charging will go way up.
This is not a simple solution.
And if electric cars really do take off, non heavily travelled train routes will simply be crushed by Uber lookalikes.
