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The Electric Vehicle Future: Where is all the power going to come from?
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nctnico:

--- Quote from: benst on February 14, 2020, 10:30:42 pm ---(F)Actual data is is totally absent. I did find some numbers elsewhere for average yearly household use in the Netherlands though: 2830 kWh. A car drives on average around 15000 km/y, so that’s around 2250 kWh. So the numbers are similar and do not differ by an order of magnitude. On average.

--- End quote ---
You don't understand the problem at all. This has nothing to do with averages but peak demand. The grid in a street is designed for a domestic load. This means that they fit a street with a transformer and wiring which is enough to feed all the homes at peak demand with some margin. Add some big extra loads and you'll see that the wiring can't handle the total load while the homes are at peak demand. Something has got to give. Even on the elaad.nl website it says 1 EVs is equal to the (peak) demand of 10 homes. The real challenge is to do the math to determine at what point the wiring is not enough to charge all EVs parked in a street sufficiently.
benst:

--- Quote from: nctnico on February 14, 2020, 10:44:07 pm ---
--- Quote from: benst on February 14, 2020, 10:30:42 pm ---(F)Actual data is is totally absent. I did find some numbers elsewhere for average yearly household use in the Netherlands though: 2830 kWh. A car drives on average around 15000 km/y, so that’s around 2250 kWh. So the numbers are similar and do not differ by an order of magnitude. On average.

--- End quote ---
You don't understand the problem at all. This has nothing to do with averages but peak demand. The grid in a street is designed for a domestic load. This means that they fit a street with a transformer and wiring which is enough to feed all the homes at peak demand with some margin. Now when all the homes are near maximum usage the margin gets thinner. Now add some big extra loads and you'll see that the wiring can't handle the total load. Something has got to give. Even on the elaad.nl website it says 1 EVs are equal to the demand of 10 homes. The real problem is to do the math to determine at what point the wiring is not enough to charge all EVs parked in a street sufficiently.

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As it says in the original AD article, peak demand is between 17.00 and 21.00h. No need for all cars to be charged during that time, and that is exactly the solution elaad.nl is promoting. Which has been talked about for years, smart charging, smart metering, it's nothing new. Investments in infra structure will have to be made, for sure, but it is nothing the grid cannot handle.

Ben
benst:
More on smart metering for EV's: I thought I'd do a little spreadsheet test to see how this works out with some data from the Netherlands. See attached image.

Netherlands average daily energy use w/o EV's is now ca. 8 kWh. I put in some guestimates how this is divided up over the day. This gave a peak power of 0.8 kW. So to keep everyone happy, adding an EV to this household should not increase peak power at any time. This leaves around 4.5 kWh of charge for the car, which is a range of 30 km. Average daily km here is around 40 km so it falls a bit short. But this is not an order of magnitude problem.

Ben
nctnico:
Not enough is not enough. Also your calculation leaves zero margin and you accounted for only 1 car per household. At some point changing / expanding the wiring in the streets will be required. The costs for this operation will mostly be driven by the amount of labour involved so it doesn't really matter how big the problem is. It is going to be costly.
benst:

--- Quote from: nctnico on February 14, 2020, 11:30:34 pm ---Not enough is not enough. At some point changing / expanding the wiring in the street will be required.

--- End quote ---

Oh please, that has been happening for the last 100 years. Plus, the average house around here has a 240 V 16 A 3 phase main fuses. (25 A optional for free.) That's 11.5 kW. Don't you think there's some overcapacity in the grid, compared to the 0.8 kW peak power in the spreadsheet I showed. Just the other week, the power co was increasing the power available here in the street. (A distribution box is in front of my house so I had a chat with them.) You know what they did? Upgraded the fuses in the distribution box.


--- Quote ---The costs for this operation will mostly be driven by the amount of labour involved.

--- End quote ---

Ya think?

Ben
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