Abstract: Apparatus and method for enabling viscous fluids to be discharged from a container. The container is provided with an outlet positioned for gravity discharge of the contents. Microwave energy is delivered to an inlet opening of the container for the purpose of heating the stored fluids in a controlled area which includes the inlet and outlet. The microwave energy is effective to heat the viscous fluids to a flowable state while fluids are simultaneously discharged from the outlet. The energy level can be controlled based on the level of viscous fluid in the tank so that the viscous fluid is not overheated.