103 points, 167 comments, 8h ago - https://news.ycombinator.com/item?id=43396853

Someone help me with my maths.

These are using 1MW. The UK national supply 2023 was 74.8GW [1]

"The Competition and Markets Authority (CMA) estimates the UK will need between 280,000 and 480,000 public charge points by 2030" [1]

So lets take a mid figure: 380,000 x 1MW = 380GW

So that is five times the national capacity. I know they won't all be going at once, but even so, that seems a ridiculous burden. Or is my calculation out by a ridiculous amount?

[1] Wikipedia

You would not charge directly from the grid.

Typically you would use flywheel energy storage in the charging station to store energy. Flywheels are relatively common in managing grid fluctuations in minutes to hour timespan. Use hour to spin up, then discharge in five minutes is 83 kW to 1 MW.

https://en.wikipedia.org/wiki/Flywheel_storage_power_system

Doesn't change the overall power usage though. It is a lot.

power != energy

It changes overall power usage. That's the point.

Energy usage does not change, but car energy usage is smaller fraction of total energy usage in the electric grid and manageable.

> ... requires silicon carbide power chips with voltage levels of up to 1,500V

I am not surprised honestly, you have them doing 80w up to 25% in 5 minutes on silicon carbide cellphone battery without active cooling.

Multiply that by thousands of cells and active cooling to keep the charging going for longer...

Time for the Dynamic Duo to do a live sell-a-thon from the White House dealership.