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Comment by Rygian

2 days ago

Charging rate of 11 kW, with efficiency of about 90%, means that the charger sucks around 12.2 kW of power from the grid, of which 1.2 kW is continually lost*, and only 11 kW is effectively being stored in the battery at any point in time.

I don't understand the mention about battery capacity (80 kWh, which would translate to around 7½ hours of charging at 11 kW, if a battery could charge at a uniform rate) or where the "9 kW lost" figure comes from.

*Which is probably useful to melt snow above the device, when installed outdoors on cold climates.

The average person is spending about $1.50 to $2.00 in electricity per day to drive a car.

This would cost $0.15 to $0.20 per average trip to NOT plug in.

Average person spending $100k on a car would likely pay that without a second thought.

  • The Cayenne seems to need about 315Wh / mile. I assume a substantial number of them are sold in California, where rates are often above $0.50/kw. I think $1.50 would get you about 9 miles.

    I drive a more efficient PHEV and spend much more than $1.50/day.