IIT Delhi develops device to generate electricity from raindrops

The device called Liquid-solid Interface Triboelectric Nanogenerator has been developed using triboelectric effect and electrostatic induction. 

The Indian Institute of Technology (IIT) Delhi researchers have designed and fabricated a device that can generate electricity from water drops, raindrops, water streams, and even from ocean waves using triboelectric effect and electrostatic induction.  

Generated electricity can be stored in batteries  

The device is called Liquid-solid Interface Triboelectric Nanogenerator. The generated electricity can be stored in batteries for further use. The device has a very simple structure consisting of specially designed nanocomposite polymers and contact electrodes and can generate a few Milliwatt (mW) power, which is sufficient to power small electronic devices such as watches, digital thermometers, radio frequency transmitters, healthcare sensors, pedometers. When compared with conventional methods, such as the use of the piezoelectric effect, the present device can generate significantly more electricity.  

Prof Neeraj Khare from the Department of Physics and his group at the Nanoscale Research Facility (NRF), IIT Delhi, have been working on harvesting electrical energy from to be wasted mechanical vibrations using the triboelectric effect. The group has filed an Indian patent on the various aspects of the use of ferroelectric polymer for harvesting mechanical energy, including the present device.  

Triboelectric effect explained 

“Triboelectric effect is a known phenomenon for a long time, and in this effect, charges are generated when two surfaces are in friction. The best example we see are sparkling lights when we move the blankets/jackets. It is only lately that it has been extensively investigated as a practical alternative for energy harvesting,” said Prof Khare. 

“The IIT Delhi research team also explored the underlying mechanism of the electricity generated when the water drop comes in contact with the solid surface and it is shown that saline water drops generate more electricity. The researchers also showed that the device can even work with ocean waves, where the water is saline, and through the ocean waves contacting the surface of nanocomposite polymer film, electricity is generated,” a statement from IID Delhi read. 

 Read more:

• IIT Delhi announces alumni awards 2021
• IIT Delhi To start BDes course from 2022-23 
• IIT Delhi launches academic outreach initiative for high school students