Price of Power and Eldritch Empowerment Lich nodes interact with spells that do not deal damage

As per topic, when used in conjunction with Price of Power to maximize the power charge effect (40% more damage) or with Eldritch Empowerment the cast of Unleash (staff skill) would consume a power charge and sacrifice ES.

This is a problem because spells that do not deal damage also do not benefit from these nodes, making it problematic to introduce them into rotation.