The USS Growler is a diesel powered, battery operated submarine. Although it carried nuclear warheads, it was not nuclear powered.
There are three large diesel generator sets that produced the electricity. This powered the subs two electric motors. It was the two electric motors that turned the two propellers there by moving the sub through the water. The three diesel generator sets also provided the electricity needed to recharge the batteries located under the crew’s and officer's quarters.
Because diesels needed fresh air and some place to exhaust their fumes, they could be used only while the sub was on the surface. The snorkel was perfected during WWII and allowed the sub to run just under the surface with only the snorkel protruding above the water, fresh air was taken in and the exhaust was vented out. This breathing pipe is located on the aft end of the Growler’s large sail.
