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Average wattage for driving at 55mph or in town

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I hear that the Model S's top end battery is capable of a whopping 270 kW of raw power (equivalent to around 140 of my 2kW kettles running simultaneously). However, that's presumably a maximum. What's the wattage (not watt hour) when driving at 55mph? Also what's the average wattage used when driving in town generally with?
 
Reports are 300 W/mile at 55 mph. If you do the product of these two numbers (300 * 55) all units but W will cancell eachother out so the answer is 16500 W = 16.5kW which is consistent with driving for about 5 hours before having used up 82.5 kWh which is 55 mph * 5 hours = 275 miles (a little optimistic).
 
Thanks I get close to your result with the stats from some specs I looked up:

85kWh = total battery capacity
300 miles = capable distance traveling at 55mph

85kWh ÷ (300miles ÷ 55mph) = 15.583333 kW

Okay that's 'only' 8 kettles or toasters running at the same time now :)
 
You'll also easily draw 40-80kW to maintain highway speed going uphill (and conversely you can see 20kW or more doing regen at highway speeds down a hill). And these are just Massachusetts hills. I'm sure mountainous roads have some interesting numbers (would love to see someone share those!)
 
I'd also add that in windy conditions, with speed constant, being with or against the wind makes a huge difference. In the prevailing winds where I live, I see a 20-40 Wh difference in my average usage when driving into the wind versus with the wind.
 
Interesting. Perhaps the 16kW figure was a bit optimistic then, and assumed a flat surface with no wind. I like the way you're given the watts usage as you're driving!

I usually run under 300 watts per mile at 55 mph
Perhaps you mean "300 watt hours per mile", since the watt is a power rating, rather than an energy amount.
 
You are correct. And the power figures given so far match my experience, somewhat limited tho since I prefer 65-75mph. At 65 or so I see around 330 wh/m, 75 is 360 or so. It goes up, but not dramatically. I'll try to pay closer attention on my next highway trip.
 
The folks who did the record with the Roadster traveled as flat as possible and fairly slowly, since it is air resistance that is most of the issue.

A constant 35-40mph could get a very good range, but good luck finding a place to do that.