What is the outside air temp during that run ? What is the wind speed and direction ? (Headwind maybe?) How much uphill on that route ? Try doing the same route at 65 mph and see what the result is.

Exactly. AC use has not been seen as significant which is because going uphill at 75 mph is a much more energy intensive thing than the AC could ever be, and is sustained for 2 miles.

Try slowing down to speed below 70mph. Going 75 mph uphill is the cause of the power loss, not the AC.

And it's not the miles going uphill, but the elevation change. You calculate ten miles drain for every thousand foot gain (hey, it rhymes!). I gain a thousand feet in two miles going up to my house every day. Your quoted wind speed of "mild" means?? 10 mph of wind is the same as 10 more mph drag. And the range already drops 25% when driving 75 over 65. So, yeah, I believe your range is down to 150. I would recommend watching Trips and slowing down. Unless you're not worried and are going less than 150 miles.

Just use the energy app, set it to the smallest increment of 5miles and check your average before you get to the hill, after you get tot he top of the hill and then beyond. The car has a LOT of ways to show you average energy use: 1. Since the last time you charged 2. Since the last time you started driving 3. Last 5 miles, 15 miles, 30 miles 4. Trip odometer A and B

Not among the ten words listed but frequently seen on the forum: Breaking ==> failing, coming apart. Braking ==> slowing or stopping using a vehicle's brakes.