From https://web.mit.edu/16.unified/www/FALL/thermodynamics/notes/node98.html https://web.mit.edu/16.unified/www/FALL/thermodynamics/notes... All other things

From https://web.mit.edu/16.unified/www/FALL/thermodynamics/notes/node98.html https://web.mit.edu/16.unified/www/FALL/thermodynamics/notes... All other things equal, range varies proportionately with efficiency. Ie, if you have 500km range at 50% overall efficiency, then at 65% overall efficiency, you have 650km range.