I'm talking about slow chargers - the kind that are 60 amps or so AC. The kind that require no expensive electronics in the charger. The kind that'll take 12 hours for a full charge.

Fast DC chargers will always cost more due to the need for expensive power electronics.

The issue is not power electronics, but power supply. You might have a 60 Amps grid supply, or even a 100Amps split phase 120/240V as is typical for newer US homes, which allows drawing 24KW from the grid at full power. Your neighbor might have the same.

But that doesn't mean everybody in your neighborhood can draw 24KW all night long. Those are maximal currents for intermittent loads like heaters, clothes driers etc. You might have a single 100KVA polemount transformer suppling a whole street and a single 15KV / 300Amp line servicing a whole neighborhood.

When everybody attempts to draw even 5-10KW in the air-conditioning season, you get circuit breaks because the main feed is incapable of supplying sufficient power. The upgrading will be done but it will take a decade or more, especially considering the push from local municipalities towards buried power feeds which are very expensive.

Electric cars consume about 20kWh/100km. If your whole neighborhood needs to draw double digit kilowatts for 10h a night, you live in a neighborhood of long distance truck drivers.

Maybe it doesn't happen every night, but only some nights. Say when everyone comes home from thanksgiving with empty batteries.

If everyone wants to fill up their tank at once, the gas stations run out of gas. This doesn't happen with any regularity, which I take as an indicator that the scenario you're describing is very rare.

The gas system has buffering and slack at many levels. Cars store more mileage. Gas stations have a buffer. Gas stations can request more trucks come refill much easier than a grid can be upgraded. I don't think you proved anything.

And yet runs on gas stations happen during crisis times and they do in fact run out of gas.

Precisely, even with that significant slack, it still happens. How frequent will be the overloads in a system with no energy storage capacity, which is sized to handle the existing load peaks and already has infrequent overloads?

The average commute in the US is 50 Km per day and if that is the average it is reasonable to assume some communities will be highly correlated above average, for example if they are 40-50 Km away from a large economic hub, a large proportion of residents will drive the 100Km roundtrip per working day. The lower price of electric comute will prompt many residences to have two electric cars driving the average every working day, for a total, again, of 100Km = 20KWh. So double digit is not exceptional, it will be the average, an extra 3KW of power for each household for the entire night, assuming an outstandingly smart grid that can perfectly level off demand.

Combine that with rare events like hot nights and large movements, psychological reactions like panic, and you have an unreliable local supply that might trip every few months without expensive upgrades.

Generally speaking, you don't need massive upgrades of local grid infrastructure to support electric vehicles.

There is plenty of capacity available, provided charging is spread out over the night and not concentrated at peak demand periods. You just need chargers that are smart enough to ensure this happens.

Even just +7 kVA per house means a complete rebuild of the grid.

1 MW would be enough for just ~150 chargers. And where would you get that megawatt at night? More base load, which means nuclear or fossil which means less niche for solar because no one would shut down such amount of base load generation each day.

Besides 60 amps isn't exactly cheap in electronics. It might not require active cooling for the cable and the battery, that's true.

> "Even just +7 kVA per house means a complete rebuild of the grid."

Only if every car in your neighbourhood is plugged in and pulling 7 kW at the same time.

Smart charging solves this, by reducing charging during demand peaks (ie: 6pm when everyone is arriving home from work and plugging in at the same time), and increasing it later in the night when more capacity is available.

However you slice it, you have to deliver say 40KWh to that many cars overnight, or they fail to charge and thus are useless. So the grid has to handle that and even if you can get rid of extreme peaks with "smartness", you can't lower the cables and switches ratings much.

First of all, the average car does not need 40 kWh every day. The average driver in the USA drives 13,500 miles per year (far more than the average driver in the UK/Europe!)

That's about 37 miles per day, so about 12.5 kWh per night on average at ~3 miles per kWh. And remember, those who are driving long distance are probably going to be using fast chargers on-route, so their domestic charging demand will be lower.

Secondly, even if they did need 40 kWh every night, that only equates to 4 kW over a 10 hour charging cycle. Easily manageable by avoiding the typical late afternoon / early evening peaks. Most grids have a lot of spare capacity between, say, 9PM and 7AM.

You fail to take into account inefficiencies in transmission and charging. That would multiply required input by a factor of two or three, depending where you measure it.

So no. Switch most commute to electric - then at first grid goes down, then power plants struggle.

"Most grids have a lot of spare capacity between, say, 9PM and 7AM" - that's not the grids we're talking about. HV circuits might not feel it, but something laid down for a suburb was scrupulously designed to carry only just enough, because it's basically burying refined metal, be it copper or aluminium.

There is no spare even 4KW for every house and never has been because that would have cost more in about everything - meters, cables, multiple stages of step-down transformers, transmission lines, generation.

Electicity is not free, never has been, and distibution costs are surprisingly a very important consideration.

> "There is no spare even 4KW for every house and never has been"

Yes, there is. It's just the timing that matters. Domestic electricity demand during off-peak overnight hours is as little as 1/3 as it is at peak time. If all those houses can run 4 kW of air conditioning, or heating, or electric ovens at 6PM, then there is 4 kW to spare at 2AM.

This issue has actually been studied in some detail by the UK's National Grid. The conclusion was that additional demand from millions of electric vehicles would cause issues if they all were charged at peak times. But, provided demand can be managed, existing grid infrastructure can cope with an entirely electric vehicle fleet with modest investments in the coming years/decades.

Fun fact: UK grid demand used to be significantly higher than it is today. It peaked at 62 GW in 2002, but it now rarely gets above 45 GW, despite significant population growth! Much of this reduction in demand is due to improved energy efficiency.

If we could handle 62 GW in 2002, then there's no reason that we can't handle 62 GW again in, say, 2042.

> If we could handle 62 GW in 2002, then there's no reason that we can't handle 62 GW again in, say, 2042.

There is - supply and grid maintenance was scaled down with demand.

The grid certainly can be rebuilt to 2002 state in UK, but this will not be cheap.

The other point that I was making is that any deviation from current patterns, like night demand significantly growing will require significant changes in generation.

> "The grid certainly can be rebuilt to 2002 state in UK, but this will not be cheap."

It doesn't need "rebuilding". The grid, broadly speaking, hasn't changed since 2002. Generation has changed dramatically, but generally the transmission lines that served old power plants do not get removed when the plants close. They're still there, still active, and are often reused (for example, off-shore wind farm built off the coast from closed coal plant).

> "The other point that I was making is that any deviation from current patterns, like night demand significantly growing will require significant changes in generation."

First you were talking about lines, now you are talking about generation. But it's the same story. Power plants get turned off and curtailed at night because there is less demand. If demand increases at night? Plenty of spare capacity available, they just need to run for longer.

> "You fail to take into account inefficiencies in transmission and charging. That would multiply required input by a factor of two or three, depending where you measure it."

I do not account for transmission inefficiencies, as this is highly variable depending on your location and grid infrastructure. But it would be extremely unusual for transmission losses to be as high as 66% like you suggest!

As for charging losses, that's something like 10%. About 90% of the energy as measured at your domestic electricity meter will make it into the battery. I did account for this, by giving a deliberately low miles per kWh figure. In reality, most EVs will get significantly better efficiency than the 3 miles per kWh that I quoted.