An energy harvesting module, comprising a pendular unit subjected to external stresses applied to the module, the pendular unit comprising a piezoelectric transducer extending, along a central axis (Δ) corresponding to a direction of greater length of the piezoelectric transducer, from a distal end to an opposite proximal end, the transducer being elastically deformable in bending between a clamped end and a free end coupled to an inertial mass, the piezoelectric transducer being adapted to convert a mechanical energy produced by oscillations of the pendular unit into an oscillating electrical signal (V OUT (t)) collected by surface electrodes of the piezoelectric transducer, wherein: - the piezoelectric transducer comprises at least one piezoelectric beam configured into two adjacent arms formed single-piece, with an external arm and an internal arm arranged side-by-side, the external arm having a proximal end fastened to a clamp and a free distal end 64), and the internal arm having a free proximal end supporting the inertial mass, and a free distal end connected to the distal end of the external arm, - the module further comprises, around the central axis (Δ), an annular mount that surrounds the piezoelectric beam at its proximal end and that comprises said clamp to which is fastened the proximal end of the external arm, and - the annular mount includes, in a central region in the vicinity of the clamp, a cavity inside which the inertial mass carried by the free proximal end of the internal arm can oscillate transversely to the central axis (Δ). the pendular unit comprising a piezoelectric transducer extending, along a central axis (Δ) corresponding to a direction of greater length of the piezoelectric transducer, from a distal end to an opposite proximal end, the transducer being elastically deformable in bending between a clamped end and a free end coupled to an inertial mass, the piezoelectric transducer being adapted to convert a mechanical energy produced by oscillations of the pendular unit into an oscillating electrical signal (V OUT (t)) collected by surface electrodes of the piezoelectric transducer, wherein: - the piezoelectric transducer comprises at least one piezoelectric beam configured into two adjacent arms formed single-piece, with an external arm and an internal arm arranged side-by-side, the external arm having a proximal end fastened to a clamp and a free distal end 64), and the internal arm having a free proximal end supporting the inertial mass, and a free distal end connected to the distal end of the external arm, - the module further comprises, around the central axis (Δ), an annular mount that surrounds the piezoelectric beam at its proximal end and that comprises said clamp to which is fastened the proximal end of the external arm, and - the annular mount includes, in a central region in the vicinity of the clamp, a cavity inside which the inertial mass carried by the free proximal end of the internal arm can oscillate transversely to the central axis (Δ). - the piezoelectric transducer comprises at least one piezoelectric beam configured into two adjacent arms formed single-piece, with an external arm and an internal arm arranged side-by-side, the external arm having a proximal end fastened to a clamp and a free distal end 64), and the internal arm having a free proximal end supporting the inertial mass, and a free distal end connected to the distal end of the external arm, - the module further comprises, around the central axis (Δ), an annular mount that surrounds the piezoelectric beam at its proximal end and that comprises said clamp to which is fastened the proximal end of the external arm, and - the annular mount includes, in a central region in the vicinity of the clamp, a cavity inside which the inertial mass carried by the free proximal end of the internal arm can oscillate transversely to the central axis (Δ).