It seems possible in theory. The air is thinner at higher altitudes, and wind resistance is a big part of fuel economy, isn't it?
Suppose you're going to make a 100 mile (160 km) trip. You have two possible routes. One is a straight shot on level ground. The other is straight, too, but it takes you up a 10% grade for the first 10 miles (gaining 1 mile in altitude), then you continue on level ground for 80 miles, and then you descend a matching 10% grade at the end.
It seems like the 80 miles of cruising on level ground at high altitude would use less battery than 80 miles of cruising at sea level (if the speeds are the same).
There will be some losses due to climbing and descending. Maybe climbing and descending is a little less efficient. Also, you're definitely traveling a very slightly longer distance. But those losses might be made up for spending the bulk of your trip in thinner air.
Suppose you're going to make a 100 mile (160 km) trip. You have two possible routes. One is a straight shot on level ground. The other is straight, too, but it takes you up a 10% grade for the first 10 miles (gaining 1 mile in altitude), then you continue on level ground for 80 miles, and then you descend a matching 10% grade at the end.
It seems like the 80 miles of cruising on level ground at high altitude would use less battery than 80 miles of cruising at sea level (if the speeds are the same).
There will be some losses due to climbing and descending. Maybe climbing and descending is a little less efficient. Also, you're definitely traveling a very slightly longer distance. But those losses might be made up for spending the bulk of your trip in thinner air.