In @JimVandegriff's excellent trailer-pulling report, we noted a climb that seemed to defy the standards of consumption. That is, we noticed that, according to Jim's records, he seemed to consume more energy climbing a steep grade than he did climbing similar elevations on a more shallow grade. The question was raised (by me) whether a nominal unit of climb (let's call it 1000ft) could cost more in terms of consumption depending on the percentage grade. @ecarfan points out that the actual physics of motion seem to support the inverse. Since there is less rolling resistance to climb 1000 feet over a shorter distance, it seems like one would do better. @vandacca points out that it may have to do with efficiencies related to torque or heat created by the work being done. I thought it would be useful to split out and discuss separately. My recollection tells me that AC induction motors are actually most efficient at full load, so that would remove the motor from the equation. I believe @ecarfan has it right with regards to the actual physics of moving an object. There's a horizontal and vertical component. What about battery discharge efficiency? Does anyone want to chime in about that?