(CNN) - Southwest Airlines is saving big on fuel, but will that translate to cheaper airfare for you? Likely, no. Southwest and other airlines are putting the money they saved from fuel and spending it on infrastructure and improvements. The airline said Thursday it expects to save more than $1.5 billion this year thanks to lower fuel costs. And Southwest ended 2014 with record profits. The airline plans to expand into Mexico and Central America this year. And the CEO is even considering flights to Cuba now that the U.S. is lifting travel restrictions there.