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Comment by dev_north_east | Hacker News Reader

Yeah, not buying it until I see the plans on how they're going to increase the national grid to power this.

I'm not familiar with Ireland's grid, but if it's anything like Britain, there is already more than enough capacity to power a fully electric vehicle fleet, provided a significant portion of charging happens at off-peak times.

This is something that has been studied in some depth in the UK:

https://theenergyst.com/millions-electric-vehicles-sooner-pr...

https://www.nationalgrid.com/group/case-studies/electric-dre...

That's not what your links say. The first link says nine million electric vehicles might require 4GW or 8GW of extra generation capacity (depending on smart technology)

But there are 38 million vehicles registered in the UK [1]; and even the optimistic 4GW is greater than the power output of the proposed Hinkley Point C nuclear reactor [2].

If 9 million vehicles need 4-8GW of generation capacity, 38 million would need 17-34GW, i.e. 6.5 to 13 nuclear power stations' worth (or the equivalent in wind or solar)

[1] https://www.racfoundation.org/motoring-faqs/mobility#a1 [2] https://en.wikipedia.org/wiki/Hinkley_Point_C_nuclear_power_...

All of the National Grid forecast scenarios assume >30M electric vehicles in 2050. You might be confusing the peak power demand (in GW) with the total energy consumption (measured in GWh/TWh).

Clearly if everyone charged their vehicles at peak times there'd be problems meeting demand. But that's not the case: EV charging is a flexible demand, and with "smart" chargers and incentives in place to encourage off-peak/overnight charging, demand peaks can be managed.

Here's the link to the full Future Energy Scenarios document where you can dig in to the figures in great detail:

http://fes.nationalgrid.com/fes-document/

I'm reading the second paragraph of your first link which states "Nine million electric vehicles on UK roads might require 8GW of extra power generation capacity if people charge them when they like. But smart charging could cut that to 4GW, potentially less, according to National Grid’s EV lead, Graeme Cooper."

I don't think I'm confused about that - it seems pretty unambiguous to me.

Right. That's a worst case scenario for peak power demand if everybody was charging their EVs at peak time. The solution is to install smart chargers, and incentivise off-peak charging so that a high proportion of charging happens at off-peak times, when there is plenty of surplus generation and grid capacity available.

Or, to put it another way: It doesn't make sense to spend billions on building new power plants just because everybody is plugging in their cars when they get home at 6PM every night and causing a huge demand spike. Smart charging and demand management is a much cheaper way to solve the problem.

The 8GW figure is for everyone charging at peak time; the 4GW figure is for smart chargers (i.e. dynamic internet-of-things off-peak charging)

So smart charging halves the need for new power stations - but doesn't eliminate it.

You're talking about electricity generation, not about the grid (which is the distribution network). Generation has to increase (by 4-8GW for 9 million cars), but the distribution network doesn't need much extra capacity because most of the charging will happen offpeak.

When they say "extra" they mean extra generation, not new capacity. The grid isn't running flat out all the time. The highest output this year was 48GW. At night, it does about 22GW. That leaves plenty spare capacity for charging cars if required.

Remember, the internal combustion engine is terribly inefficient. It was attractive because it's small enough to fit in a personal vehicle and the liquid fuel has so much energy that you can throw most of it away without bankrupting yourself, but that means there's a big difference between how much energy is used by a conventional ICE car and how much electricity is needed (and thus passes through the grid) for an electric car with the same power.

You might easily get rid of 10GW of ICE cars and only need to buy 2GW of electrical grid capacity to replace that.

There are lots of more immediately noticeable consequences while you wait decades for any global climate effects, the air on city streets is better, a bunch of land used to store incredibly dangerous liquid fuel where people want to buy it is released for new housing, maintenance costs on cars fall. I don't think it'll take long for the story to be "Why didn't we do this sooner?" rather than "Why did we bother trying this?"

FWIW I'm not arguing against it.

Its pretty simple. Change power pricing to be cheaper at off peak times and have car chargers wait until the price drops below x before starting charging so everyone's car charging is spread out overnight when the grid would be mostly unused.

> Change power pricing to be cheaper at off peak times

That's already the case. But with 2 million or so cars sucking juice at night, that will no longer be "off peak" and of course the grid needs some downtime which will be harder to do then.

Ireland's electricity is quite dirt. Coal and peat are being phased out, so they already need to replace existing grid generators and now top up with lots of new generation too.

As said, I'm sceptical about it all until I see the grid plans.

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