Not wanting to get dragged into this but I thought some vehicle registration facts may help calm things down.
In 2020 2.1 million new vehicles were registered down 27% on 2019 (
https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/985555/vehicle-licensing-statistics-2020.pdf
Now let's assume when all EV is the only option here in the UK (ignore hydrogen) then it would be reasonable to assume new all EV registration will be 2.0 million? (lower still as people use public etc.)
Also let us *assume* that these all have 60kWh batteries. (21.6MJ say 22M Joules)
Also let us *assume* a normal distribution of distance/charge usage (probably an excessive assumption) so 50% and thus 2.0 million vehicles using 30kWh of electricity per day would require 2,000,000 * 22,000,000 Joules of energy = 44,000,000,000,000 Joules of energy. 44 Tera Joules (44 M * M Joules).
Assuming this is delivered over a 12 hour period then that is (approx) 4 M*M Joules per hour. 4,000,000,000,000 = watts * 60 * 60 * 12 => watts = 93MW load for 12Hours
So assuming I've done the maths and stats correctly then when we go to all electric new vehicles the initial year power requirement will be an extra 93MW load, say 100MW. By year two that will be 200MW increasing year by year.
I don't think we can say/conclude that in the future all the currently licensed vehicle in the UK will remain the same (or higher). There will be a big EV increase for sure but there will be a) classics running on fossil b) possible reduction as (in their government wildest dreams) a huge uptake in public transport brough about by taxing people off the road!
Now for my disclaimer. I did these fag packet calculations, based on dubious assumptions, but given the assumptions I think/hope my maths if correct.
What I've tried to add to this discussion is not watts, not watt hours, but gone back to basic energy in Joules. This measure of energy is absolute. How you deliver the required energy (per day) over time (charge period) and by source (fossil, hydro, atomic solar, wave, etc. is like the assumed stats/data in my post completely open to alternative evaluations.
For example we could say our required total EV can be split off over 24 hours where we power share with countries in different time zone. Currently the EU is out only power import and at best we can get two or three hour leverage.
Point of my post. (Tell me if I'm wrong) is that running an all EV requires so many Joules of energy per day. How you quantify average usage, number of vehicles, time to deliver, and charge rate is totally up for grabs.
I hope by bringing the base energy of Joules required to run an average vehicle on average usage is helpful.
Now going into my bunker
I'm not sure I understand the need to conversion to MJ
Go with your assumption of a 60KWh battery and assume 250mile range on a full 60KWh charge which is not far off what a lot of 60kWh battery cars will do.
An *average car you could argue might do 1000 miles a month/12,000 miles a year.
This means your *average electric car is only going to need charging once a week.
*except if you look up the average miles we do actually drive in the UK in our cars its dropped quite a lot and 12,000 miles a year is now more like 7,400 miles a year. so about 62% of what people assume.
So its actually more like 32-33 charges a year.
Something like a Polestar 2 has a 64KWh battery and on an 11kW (doesn't need 3 phase) charge in about 6hrs 40 mins.... call it 7hrs for the sake of ease.
11kW over 7 hrs = 77kWh worst case 33 charges a year = 2541kWh a year.
To put how little amount of power that is, in perspective. My PC that I have just built.
200watts drawn at the plug so 200Wh x 24 hrs in the day (its left on all the time and it is always drawing about or slightly more than 200W)
That's going to 4.8kWh, x 365 days a year = 1752 kWh.
I pay 14p per kWh and the car would therefore cost £355.74 a year to charge,
The PC costs about £245.28 a year to run (which is scary
)
Any way 2 Million cars - about ~5TWh
20 Million cars about 50TWh. add another 50% for 30Million cars you're now looking at more like 75TWh per year in a country that usesl over 300TWh a year
But that's just assuming 60kWh cars so there are a lot of cars with much bigger batteries and batteries are getting bigger, also a lot of cars with much smaller batteries. so they take longer or less time to charge, bigger means more power used, smaller means less power used.
This math's in no way represents the real world but over all. it shows if this where the case the total increase in annual demand for electricity would increase by 75TW to 375TW.
Now assume that every car replaced runs on petrol, and that petrol car does 50mpg (which they really really don't but lets just assume)
That car would use 148Gallons of fuel.
a gallon of fuel might use 10 - 12kw of electricity from the grid to refine from crude oil
148G x 12kW per G and is going to equal 1776kWh per year in electricity to make the petrol to power that car.
(remember the electric car used only 2541kWh per year.
1776 * 30M = 53.28TW.
75-53 = 22TWh.
So every if every car in the UK suddenly over night became electric.
and we stopped making the millions of gallons of fuel for running the old petrol engines which have now all disappeared, we would only need an additional 22TW of electricity per year.
The country uses 300TWh per year. That is actually less than the 10% stated in the national grid article. but assumes a very fixed set of circumstances.
Factor in my estimate being completely short by 25% (22TWh + another 25%) and you still just scrape under the claimed 10% extra power needed per year.
back in 2002 the Grid used 62GW at its peak, that is to say the grid is capable of producing 62GW (actually the grid can produce a lot more than that. even now) but we use 16% less power these days than we did in 100W light bulb, no one had ever heard of energy saving anything - 2002.
Basically this goes to show there is more than enough capacity in the grid right now to switch every single car in the UK to electric power.
it also shows that a constant 11KW draw on the grid all day every day would be enough to charge 3.42 cars from empty to full which only need to be charged once every one and a half weeks...
If my math's is right hear one 11KW home charger that doesn't need anything like a 3 phase supply... if running 24/7 365 if you just plugged it into another electric car the second it finished charging one and the next and another.
That one 11KW charger would keep 35 cars per year
The final things I have learned from this little exercise is that it costs about the same amount of electricity to refine enough fuel to travel 7400 miles as it does to run my PC for a year.
and that to run an electric car an average amount of miles each year would cost about the same (slightly less) as 3 x 100W lightbulbs being on 24/7.
