On Wednesday, I departed just before noon from The 2015 Open Minds Technology & Informatics Institute in Washington, D.C. for home in Connecticut. I learned a lot more about the Tesla during the trip. The AutoSteer beta feature continues to be impressive. It worked just fine through two tunnels, over bridges, and even in heavy rain. The feature is ideal for major highway driving. I learned to stay in the middle lane of I-95. The right lane is occasionally problematic because the white lane markers are often not clear and the car can get confused about whether to exit or continue straight.

The drive home was about 300 miles. I stopped in Newark, DE and charged up to 230 miles, which I expected to be more than enough to get me home. I did not realize how much additional electricity it takes to drive at 70 instead of the speed limit. Once I was well past the last charging station on my route to home, I realized I might have a problem. When I got on Interstate 684 my dashboard indicated I had 30 miles of electricity left and my GPS showed I had 32 miles to go. I called Tesla tech support and they told me to slow down to elongate the remaining charge. They stepped me through how to use the energy app to display the expected remaining range based on the past five miles of driving history. I drove at 55 mph and got home with 5 miles to spare. If I had stayed 10 minutes longer in Newark, I could have charged to 255 miles of range and had a much more relaxing final half-hour of driving. Lesson learned.