Here, we analyze energy transformations in the outer hair cell and its effectiveness as a piezoelectric-type actuator in the cochlea. The major modes of energy are introduced, and a method to estimate the coefficients of their tension-dependence is proposed. Next, we derive balance of the mechanical and electrical parts of energy, and show two forms of the active energy associated with the motors driving electromotility. The two forms of the active energy, stored mechanical energy, and external electrical work are then introduced as functions of voltage and applied force. We use the energy balance to introduce and estimate the effectiveness of the cell’s electromotile response.

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