The invention provides a hygroelectric charging and power management system. The system comprises at least one single layer or a bilayer of flexible hygroelectric polymer stacked together in series to generate power on collision with a water molecule, and at least one rechargeable battery having an input terminal and an output terminal. The input terminal is electrically connected to the single layer or the bilayer of flexible hygroelectric polymer to receive and store the generated power. The system further comprises at least one charger module to modulate between the single layer or the bilayer of flexible hygroelectric polymer and the rechargeable battery. The system applies Pulse Width Modulation (PWM) on the charger module to balance real-time recharging of the battery and to ensure constant power supply to a device under active load.