Driving Tesla Model S as fast as you can with Supercharging.

With Tesla adding an Autobahn tuning package, it made me wonder if driving fast in a Model S would just leave you hanging around the SuperCharger more often.  Perhaps a little bit of calculation can shed some light.

First, I started with a graph from Tesla of battery consumption versus speed.  Unfortunately that graph only went up to 80 mph, so I had to extend it (yes I know that exponential is probably not exactly correct, but it's close).

Having that data, I needed to make some assumptions about the Superchargers.  If they are 120 KW, they can charge an 85KWH battery in 0.708 hours.  Sure, I know it would take much longer than that because the last 20% of charge is slow, but I'm just trying to get a rough estimate here.

So with some simple math, we can figure out the "running time" and the "charging time" and compute an "aggregate MPH".

			Running	Charging	Total
Speed		range	Time	Time	Time	Agrregate
miles/hour	WH/miles	(miles)	hours	hours	Hours	MPH
10	220	386	38.6	0.71	39.34	9.8
15	195	436	29.1	0.71	29.77	14.6
20	190	447	22.4	0.71	23.08	19.4
25	190	447	17.9	0.71	18.60	24.0
30	195	436	14.5	0.71	15.24	28.6
35	200	425	12.1	0.71	12.85	33.1
40	215	395	9.9	0.71	10.59	37.3
45	225	378	8.4	0.71	9.10	41.5
50	245	347	6.9	0.71	7.65	45.4
55	265	321	5.8	0.71	6.54	49.0
60	285	298	5.0	0.71	5.68	52.5
65	315	270	4.2	0.71	4.86	55.5
70	340	250	3.6	0.71	4.28	58.4
75	365	233	3.1	0.71	3.81	61.1
80	400	213	2.7	0.71	3.36	63.2
85	429	198	2.3	0.71	3.04	65.2
90	463	183	2.0	0.71	2.75	66.8
95	501	170	1.8	0.71	2.49	68.0
100	542	157	1.6	0.71	2.28	68.9
105	586	145	1.4	0.71	2.09	69.4
110	633	134	1.2	0.71	1.93	69.6
115	684	124	1.1	0.71	1.79	69.4
120	740	115	1.0	0.71	1.67	69.0
125	800	106	0.8	0.71	1.56	68.2
130	865	98	0.8	0.71	1.46	67.1

That puts the optimal speed (in a time sense) at an impressive 110 mph.   Realistically, optimal speed will probably be a slower than that due to charging issues.

Unfortunately, the aggregate speed is only 69 mph considering the charging time.  It will mean driving for 1.2 hours and then charging for 0.71 hours.  That might be slightly painful.

The only thing worse, would be to go for optimal efficiency and drive at 25 miles./hour which would be 17.9 hours of driving and 0.71 hours of charging.  Bathroom break anyone?

table test

This is a test of exporting from Excel

EV Monthly Sales

2013	Chevy	Nissan	Toyota	Ford	Mitsu	Toyota	Honda	Honda	Ford	Ford	Smart	Chevy	Fiat	Tesla	Monthly
Mon	Volt	Leaf	PiP	Focus	i	RAV4	Fit	Accord	C-Max	Fusion	ED	Spark	500E	Mod. S	Total
Jan	1,140	650	874	81	257	25	8	2	338	0	2	0	0	1,200	4,577
Feb	1,626	653	693	158	337	52	15	17	334	119	0	0	0	1,400	5,404
Mar	1,478	2,236	786	180	31	133	23	26	494	295	0	0	0	2,300	7,982
Apr	1,306	1,937	599	147	127	70	22	55	411	364	0	0	0	2,100	7,138
May	1,607	2,138	678	157	91	84	15	58	450	416	60	0	0	1,700	7,454
Jun	2,698	2,225	584	177	39	44	208	42	455	390	53	27	0	1,350	8,292
Jul	1,788	1,864	817	150	46	109	63	54	433	407	58	103	150	700	6,742
Aug	3,351	2,420	1,791	175	30	231	66	44	621	600	182	102	160	1,300	11,073
Sep
Oct
Nov
Dec
YTD	14,994	14,123	6,822	1,225	958	748	420	298	3,536	2,591	355	232	310	12,050	58,662