We recently purchased a Tesla Model X Long Range Model 2017, we went to the San Antonio TX for a minor repair and we got there with still about 30-40 miles to go. After the repair they fully charged it our Tesla..it was showing 289 mileage range. We traveled to Laredo, TX about 173 Miles distance...and about 20 miles from our destination the battery was completely drained. Me and my wife were praying to God just to make it home...we later learned that the batteries have a reserve of about 10-20 miles. We were traveling at an average of 80 miles with the AC on and it was at night. Could this have cause the battery to drain.?? I was planning on traveling a lot with this car but now I have my doubts. How can we prevent this? In Laredo, TX AC is a necessity we can't drive without the AC on.