jackdaww wrote:but i wonder how much the national electricity grid has to be upgraded to handle all the oil based power that is currently used on the roads .
is it double ? triple ? DAK ?
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In relation to EV car users you have to consider when most people will be charging their car, and how frequently.
Already most charging happens overnight because that is when the cheap electricity is, and it is cheap because there is a surplus as others don’t want it (offices, shops, most homes, etc.) - although whether it stays cheap with increased EV demand is a good question - but if it doesn’t then that will be a bit of an issue for those with storage heaters who also rely on cheap overnight electricity, but then that will blow a hole in the getting rid of gas boiler government policy.
Charging overnight is convenient for most people; plug the car in and go in the house and next morning the car is ready. Less time actually doing anything than you would spend at a petrol station.
Then how frequently - my EV has a range of 240 miles, which if you think that 8,000 miles a year is on average 155 miles a week, then on average it only needs charging once a week with around 35kWh.
So the amount of charging done at peak times is far lower than the consumption off-peak - some people charging at work (usually because it is offered free) or people needing to top up on long journeys. But most people will choose to charge at 5p/kWh at home and not 50p/kWh at a motorway fast charger.
And then the other factor is that to get the grant to install a home charger it must be a ‘smart’ charger that is installed now. Already I plug my car in at 6pm and tell it I want a full charge by 7am, but to use cheap electricity, and let the charger decide when to do it. Do I care which four or five hours it charges in the 13 hours between 6pm and 7am or whether it is 30 minutes here and an hour there; no, provided the car is charged by 7am. So rather easy for the network to balance the load across all the cars connected to the grid if it needed to.
As it is I can see from the charts provided by the charger that it usually gives the car a half hour charge at the start of the cycle, I assume to check the information it is getting from the car about the battery status is accurate (the car and the charger are linked both through mobile phone networks to talk to each other), and then gives the bulk of the charge later in the charge period.