The embodiments describe monitoring user activity to estimate the amount of power generated by piezoelectric fabric disposed in an article of clothing, where the piezoelectric fabric is configured to generate electrical energy in response to user movement that is stored in a power supply device, and where the power supply device is configured to provide power to a charging coil disposed in the article of clothing for charging an electronic device. Upon determining the estimated power is insufficient to charge the electronic device to a threshold power level, a user exercise is selected which is predicted to generate sufficient power using the piezoelectric fabric to reach the threshold power level. A prompt is outputted to the user to perform the user exercise.