Coasting Technique
OK a few days late on my end-of-October update:
jomo25 312 8467 AZ 60 19 1 11/01/13
I mean just barely at 312. It flipped over about 1 min before I reached my garage to snap the pic. The next morning it flipped back to 313 the first few miles, but now settled back to 312 range. And with the perfect temps here now, it'll probably continue to drop for another couple-few months or so.
I am an avid user of coasting technique and have posted extensively on that at the Tesla Forum.
Using the coasting technique and keeping up with the traffic flow, I nevertheless easily beat even the Ideal Range as shown in the instrument cluster, having an average of 260 Wh/mile even in temperature in the high 30's and darkness. The technique is not in any way harmful for the car and gives an extended range, which is very good in Sweden, where we lack any kind of infrastructure for charging EV:s.
Here is a copy of that thread
Already now: sorry, maybe too long, but I try to be thorough.
Trip: Home - pick-up friend and a LOT of luggage - Stockholm (S) - Norrköping (N).
Pause 5 hours, no charging.
Return: N-S - Airport.
I think this is relevant, since 100 miles of the trip is identical, but in opposite directions. Measurements in European standard [US within square brackets]
0610 Start from home. Range Charge 100%, finished 15 mins before starting trip.
4 degrees C [39 F]. Dry road. Pitch dark. Battery cold.
0630 Pick-up and pack. Trip A reset
0650 Entering freeway (heavily trafficked) Trip B reset.
0850 Reaching N. Temp 8 C [47 F]
Spent most of trip talking, not particularly concentrating on coasting, but it was used intermittently.
Consumption: Home - Pickup 16 km [10 miles] 2,7 kWh
Pickup - S: 15,2 km [9,5 miles] 2,8 kWh bumper to bumper traffic
S-N: 161 km [100,5 miles]: 26,0 kWh Heavy traffic, average speed 80 kmh [50 mph]. I did NOT upset traffic flow, but melted in.
Average Consumption Home - N 165Wh/km [264 Wh/mile]
S-N 162 Wh/km [259 Wh/mile]. Total consumption 191 km [120 miles]: 31,5 kWh
Energy Bar at 64% Energy App remaining Range 50 km [31 miles] Average: 243 km [162 miles]
Dashboard Typical: 237 km [158 miles] Rated/Ideal: 297 km [185 miles]
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Return trip. 9 degrees [49 F]. Light half trip. Dry road. Alone in car, no payload. Here I "hitch-hiked" with a lorry that kept a steady 90 kmh [56 mph], but so far behind that I didn't use slipstream, and I made a conscious effort to drive cheaply, using coasting, while not upsetting traffic rhythm.
First a few km/miles to warm up Battery, then
N-S same 161 km [100,5 miles] plus another 39 to airport, together 200 km [125 miles] 29,6 kWh, or an average of 148 Wh/km [237 Wh/mile].
Total consumption Home-N-Airport 399,1 km [250 miles]: 63,1 kWh. Energy Bar at 26%. Remaining Range Energy Bar: 74 km [47 miles].
Average consumption whole trip: 158 Wh/km [253 Wh/mile]
Remaining Range Dashboard Typical: 74 km [47 miles]
Rated/Ideal: 93 km [58 miles].
Remaining Range Energy App 50km [32 miles] Average: 109 km [68 miles].
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Difference Dashboard Typical Range end first leg (N) to complete trip (237-74 km) = 163 km [102 miles]
Difference Dashboard Ideal/Rated Range end first leg (N) to complete trip = 205 km [128 miles].
REAL distance end first leg (N) to complete trip: 208 km [130 miles].
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Conclusions:
It would seem that driving the car with single occupancy in rather cold weather, with headlights on half the trip, and keeping an average speed of 90 kmh [56 mph],
using coasting technique actually consumes slightly less energy than even the Ideal Range setting.
The forecast about Range, using available data from the return trip indicate that the car, using coasting technique, averaging 90 kmh [56 mph], also in these semi-hard conditions, and assuming an available energy after reserves etc of 75 kWh (it is probably more) should be able to go exactly 507 km [317 miles].
QED and sorry for the length of this.
I just saw that in another thread "pgiralt" says that we get to use 81,1 kWh.
If that is true, the range with "my" coasting technique in the conditions given in the post above would be
548 km [342,5 miles],
assuming a warm battery. If not warm deduct 8 km [5 miles].
Of course, given 20 degrees C [68 F] rather than 9 [49 F] and no darkness, this would be even better.
Robert von Bahr, one of Sweden's 10 or so happy Tesla S owners.