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Old 06-08-2019, 12:37 AM   #4 (permalink)
bwilson4web
Engineering first
 
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Join Date: Mar 2009
Location: Huntsville, AL
Posts: 843

17 i3-REx - '14 BMW i3-REx
Last 3: 45.67 mpg (US)

Blue Bob's - '19 Tesla Std Rng Plus
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Thanked 248 Times in 157 Posts
SUPERCHARGER

One of my first tests was to use a dash cam as a video recorder of SuperCharger sessions:
  • > 60kW - it costs $0.26/min to charge
  • =< 60 kW - it cost $0.13/min.
There is no advantage to carry extra miles to the next charger but you must reach the charger. By adjusting speed to maintain a minimum reserve miles, you can reach the next SuperCharger with 15-30 miles of reserve charge. This gives the fasted charge rate at a cost of ~$0.16/kWh, or ~$0.04/mi. Below 60 kW, the price goes from $0.13/kWh to much higher at slower rates but sometimes you need the range. Rule of thumb:
  • ~16 minutes above 60 kW gives ~50% charge, ~120 miles
  • ~70 minutes gives a 100% charge
Our charging protocol is my wife and I do a biology break and I leave her there for refreshments. I park at the SuperCharger and walk the dogs back to where the wife is. A short break and I return to the car and drive back to load the wife and dogs.

With gasoline costing ~$2.50/gal, the Model 3 SuperCharger costs return about 64-94 MPG depending on weather and use of AC or other accessories.

Bob Wilson
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2019 Tesla Model 3 Std. Range Plus - 215 mi EV
2017 BMW i3-REx - 106 mi EV, 88 mi mid-grade
Retired engineer, Huntsville, AL
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