An aerosol generation system (36) for generation of an aerosol from an aerosol-forming precursor comprises: an electrically operated heating system (30) to heat said precursor to generate the aerosol;a flow path (18) for transmission of flow, including the aerosol, to a user; the heating system arranged in fluid communication with the flow path; and electrical circuitry (8). The electrical circuitry (8) is configured to determine a characteristic associated with a second order time derivative of a property of electrical energy through the heating system, and to determine a property related tothe flow of the flow path based on the characteristic of the second order time derivative.