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I think this underestimates the massive infrastructure investments those charging poles would need to work. I live in a medium density European town (about 1000

I think this underestimates the massive infrastructure investments those charging poles would need to work. I live in a medium density European town (about 1000 inhabitants/km2, think 4-5 story buildings on average). In residential areas the whole street is lined with parked cars on both sides. To charge these, one would need something like 1MW charging per every 4 cars, which means every 20m of the road, on both sides. So 1km of inner city street would have new electricity demands of about 100MW for fast charging. Even overnight charging at say 10MW per km of road would mean the complete energy infrastructure of the complete town would have to be changed. Edit: Inserted a line break before the last sentence because apparantly almost every replier overread that one :)

pedrocr 5y ago
> To charge these, one would need something like 1MW charging per every 4 cars This is massively overestimated. 250kW per car is great for fast charging on road trips but for overnight charging it would be enough to charge a car 30+ times in a single night. 3 to 7kW is more than enough. The grid for that is already there and the chargers can even coordinate to not exceed maximum power if everyone plugs in at the same time and draws the maximum. Almost no infrastructure in the town will need to be changed, the existing grid that supplies all the houses will be enough. After all those cars are owned by people that have electricity at home and are practically not using it while they sleep.
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bob33212 5y ago
Autonomy and ride sharing is the only answer to this problem. Most people who live a dense European town are not driving long distances every day. SO the should just rent a car on the days they need one or take an autonomous or non-autonomous taxi. Those cars do not need to be parked on those specific streets at night.
vardump 5y ago
> To charge these, one would need something like 1MW charging per every 4 cars, which means every 20m of the road, on both sides. I think your numbers are off by at least two orders of magnitude. Let's say an average BEV travels 20000 miles per year and that it consumes 400 Wh/mile. Traveling 20k miles per year takes about 21 days assuming 40 mph average speed. If we assume the car is charging the rest of the time, average power required is (400 Wh/mile * 20000 miles) / (1 year - 21 days) = 0.968 kW average charging power! That's quite a bit less than 250 kW per car (well, 1 MW per 4 cars) you suggested! It'd still be below 2 kW, even if the car is charging just 50% of the time it's not in use. Other way to think about is charging from empty to full battery with 11 kW of power: (80 kWh) / (11 kW) = 7.27 hours. Please also remember charging the battery full would be a rather rare scenario. I'd be surprised if you need even 10 kW power allocation for each 4 cars being charged — 1% of what you suggested. Simply because the batteries in most of the cars are full most of the time!
- labcomputer 5y ago
  The plural of anecdote isn't data and all that, but: My personal experience of driving electric cars for many years is that home charging from a Level-1 (120V, 8A ~= 1kW) plug is completely sufficient for all of my in-town driving needs.
dagw 5y ago
I also live in a medium density European city and charging poles have been popping next to parking spaces an impressive rate over the past year or so. 2 years ago I might have agreed with you, but today it would absolutely be possible to own an electric car if I lived back in my old apartment without its own parking space.
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ableal 5y ago
> one would need something like 1MW charging per every 4 cars, 10 kW per 4 cars is plenty enough. I charge overnight a 24 kWh Nissan Leaf (< 10 hours a couple of times a week), and just use a 2.1 kW EVSE to charge at a standard socket on a 16 A circuit breaker. If those were available at all parking spots in the city (say from city lamps), everybody could have electric cars.
thatfrenchguy 5y ago
No, you'd need around 6-7kw per car.

pedrocr 5y ago

> To charge these, one would need something like 1MW charging per every 4 cars This is massively overestimated. 250kW per car is great for fast charging on road trips but for overnight charging it would be enough to charge a car 30+ times in a single night. 3 to 7kW is more than enough. The grid for that is already there and the chargers can even coordinate to not exceed maximum power if everyone plugs in at the same time and draws the maximum. Almost no infrastructure in the town will need to be changed, the existing grid that supplies all the houses will be enough. After all those cars are owned by people that have electricity at home and are practically not using it while they sleep.

deleted 5y ago

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bob33212 5y ago

Autonomy and ride sharing is the only answer to this problem. Most people who live a dense European town are not driving long distances every day. SO the should just rent a car on the days they need one or take an autonomous or non-autonomous taxi. Those cars do not need to be parked on those specific streets at night.

vardump 5y ago

> To charge these, one would need something like 1MW charging per every 4 cars, which means every 20m of the road, on both sides. I think your numbers are off by at least two orders of magnitude. Let's say an average BEV travels 20000 miles per year and that it consumes 400 Wh/mile. Traveling 20k miles per year takes about 21 days assuming 40 mph average speed. If we assume the car is charging the rest of the time, average power required is (400 Wh/mile * 20000 miles) / (1 year - 21 days) = 0.968 kW average charging power! That's quite a bit less than 250 kW per car (well, 1 MW per 4 cars) you suggested! It'd still be below 2 kW, even if the car is charging just 50% of the time it's not in use. Other way to think about is charging from empty to full battery with 11 kW of power: (80 kWh) / (11 kW) = 7.27 hours. Please also remember charging the battery full would be a rather rare scenario. I'd be surprised if you need even 10 kW power allocation for each 4 cars being charged — 1% of what you suggested. Simply because the batteries in most of the cars are full most of the time!

labcomputer 5y ago
The plural of anecdote isn't data and all that, but: My personal experience of driving electric cars for many years is that home charging from a Level-1 (120V, 8A ~= 1kW) plug is completely sufficient for all of my in-town driving needs.

dagw 5y ago

I also live in a medium density European city and charging poles have been popping next to parking spaces an impressive rate over the past year or so. 2 years ago I might have agreed with you, but today it would absolutely be possible to own an electric car if I lived back in my old apartment without its own parking space.

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ableal 5y ago

> one would need something like 1MW charging per every 4 cars, 10 kW per 4 cars is plenty enough. I charge overnight a 24 kWh Nissan Leaf (< 10 hours a couple of times a week), and just use a 2.1 kW EVSE to charge at a standard socket on a 16 A circuit breaker. If those were available at all parking spots in the city (say from city lamps), everybody could have electric cars.

thatfrenchguy 5y ago

No, you'd need around 6-7kw per car.