Fuel usage help

[Danger]

thanks , i will try that, i thought that expending batteries then surfacing to recharge would use less fuel.
also. i have not seen any refueling stops, just ports, so i leave pearl and head to midway, refit , then go on my way. other than the ports, i have never seen any refueling stops.

i will try what has been suggested and see what happens.

thanks again.
S-!