Turning Rain into Energy

Engineers in Grenoble, France, are finding energy in the most poetic of places: raindrops. At Research Institute CEA, energy from rain showers is being cultivated transformed into electricity with the help of a plastic called PVDF (polyvinylidene difluoride). PVDF is piezoelectric, which means it produces an electric charge when mechanically deformed.

ABC Reports:

[Raindrop-powered energy] could be used with solar power to scavenge as much energy from the environment as possible, or to power tiny, wireless sensors designed to monitor environmental conditions.

“Our calculations show that even in the most unfavourable conditions, the mechanical energy of the raindrops … is high enough to power low-consumption devices,” says Romain Guigon, a French research and development engineer at the research institute CEA Leti-Minatec in Grenoble.

… Guigon and his team embedded electrodes into a thin membrane of PVDF, just 25 micrometres thick.. As the drops hit the material, they create vibrations, which creates a charge. The electrodes recover the charge for use as power.. The researchers found the system could scavenge 12 milliwatts from the largest drops and generate at least 1 microwatt of continuous power.

According to peers in the field, the next step to making this a practical alternative source of energy would be to investigate how to effficiently convert the power harvested from the raindrops to meet the minimum amount of current and voltage to power even the smallest of sensors. If developed further, the technology could potentially be put to use in industrial AC systems, where condensation forms readily.

ABC Online: Vibrating Raindrops May Power Our Home