I've made many dozens of trips into the mountains in the last 5 years in my ev, most of them 4500 ft up over the 8900 ft pass at Mt. Rose in the Sierras. I've always found that as long as the trip is a closed loop (net elevation gain zero), my energy/mile is about the same as traveling on level ground (I travel at the speed limit going down using only regenerative braking).
Going up a 5% grade (~2.9 degree incline angle) I use about 2.5x as much energy as on level ground. For example, going up 9 miles, 2500 ft elevation gain, I use 4155 Wh or about 460 Wh/mile, whereas round trip average is about 190 Wh/mile. Going down the same hill I gained 1012 Wh from regen, or about 49% of the vehicle's potential energy at the top, and about 24% of the energy used to go up the hill. I used regenerative braking to hold at the 50 mph speed limit going down. The energy/mile required to go uphill is the energy/mile used on level ground plus the product: vehicle weight*sin(theta), where theta is the overall incline angle, since the work done against gravity is force*distance = distance uphill*vehicle weight*sin(theta). I've been told a number of Tesla S's have been towed to the EVSE in Truckee CA because their drivers failed to account for this additional force when estimating their range. The opposite occurs too...a Tesla S driver told me he gained 18 miles range coming down the 4500 ft off Mt. Rose. Actually he only gained around 5 or 6 miles, the rest is inflation of the calculated moving average due to the 15 mile distance down. The Leaf guessometer people are familiar with that...I expected Tesla to do better though. -- View this message in context: http://electric-vehicle-discussion-list.413529.n4.nabble.com/As-an-aid-when-recommending-an-EV-to-someone-else-tp4670782p4670806.html Sent from the Electric Vehicle Discussion List mailing list archive at Nabble.com. _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
