Protect American Power Infrastructure Act This bill prohibits certain transactions that involve using equipment used in bulk-power system substations, control rooms, or power generating stations to provide power for defense critical electric infrastructure in the United States if a foreign adversary owns or exercises influence over the equipment. Examples of such transactions include transactions that (1) involve equipment designed, developed, manufactured, or supplied by persons owned by, controlled by, or subject to the direction of a foreign adversary; and (2) pose an undue risk of catastrophic effects on the security or resiliency of such infrastructure. However, the Department of Energy may approve transactions if it designs or negotiates measures to mitigate such risks.