A dispensing apparatus including a product dispenser in which product is dispensed by manual movement of an activation mechanism as, for example, by moving a lever with a person's hand, arm or foot. The dispensing apparatus includes a piezoelectric electrical generator for generating electrical energy as a result of the manual movement of the activation mechanism. The piezoelectric generator is carried on an elongated cantilevered spring member which biases an activation mechanism to return to an unbiased position after deflection by a user to dispense fluid. The electrical energy from the generator may be utilized in the dispensing apparatus to power a data communication unit for receiving information about the product dispenser and transmitting the information to a receiver, preferably but not necessarily wirelessly. The relative amounts of electrical energy generated may be used to estimate the amount of fluid dispensed and the extent to which a fluid reservoir is full.