>From a Physics perspective, adding elevation increases your potential energy (which comes out of the battery in an EV) Which you gain back upon descent. Formula: Ep = mgh In Earth's gravitational field, near earth the g = 9.81 m is mass in kg h is height in meters.
So, using some random rounded numbers (fill in your own favorites and repeat): m = 2,000 (4400 lbs truck) h = 300 (almost 1000 ft as was the question) and let's assume it is a pickup truck, so it needs about 350 Wh per mi, so 4 mi equates to 1.4 kWh of energy. Ep = 2,000 x 9.81 x 300 ~ 6M (rounding 9.81 to 10 we get 6 million) Joules. One Joule is equivalent to one Watt-second. So, one Watt-hour is 3600 Joules (since there are that many seconds in an hour) 6M / 3600 = 1,667 Wh = 1.7 kWh Indeed, an elevation gain of 1,000 ft (~300 meters) for a 4,400 lbs truck costs at least as much energy as going 4 miles on flat road. In fact, for the relatively heavy truck it is even over 5 miles. For a lighter car, the amount of energy invested in elevation change might be less. NOTE that this energy is *on top of* the distance you'd need to drive to get this elevation change. So, if you take this truck, drive 3 miles to gain 1,000 ft then the battery SoC would look as if you had done 3 + 5 = 8 miles. And, you might need to account for higher losses in the components at higher power level as well, but that is a secondary effect. If you turn that truck around to go down 1,000 ft in 3 miles, the battery will be re-charged with the difference between The 3 miles you are driving and the 5 miles of range you are recouperating from the height change, so your SoC should Regain 3 + -5 = -2 miles. As a result, the SoC is showing the total of 8 + -2 = 6 miles after driving 3 miles up and 3 miles down And ending up at the same height as you started. Laws of Physics still intact. Hope this clarifies, Cor. -----Original Message----- From: EV [mailto:ev-boun...@lists.evdl.org] On Behalf Of Robert Bruninga via EV Sent: Wednesday, May 03, 2017 8:06 PM To: Electric Vehicle Discussion List Subject: [EVDL] EVs and altitude? I think I saw a reference that every 1000' climb in elevation is about the same as 4 miles on level ground. Is that the general rule of thumb for EV's? Bob, WB4APR -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20170503/35bc a999/attachment.htm> _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org Read EVAngel's EV News at http://evdl.org/evln/ Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA) _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org Read EVAngel's EV News at http://evdl.org/evln/ Please discuss EV drag racing at NEDRA (http://groups.yahoo.com/group/NEDRA)
