A large hydroelectric dam or wind farm is perhaps the first thing that comes to mind when thinking about using water or wind to generate electricity. But consider a smaller scale. Italian researchers have developed an energy harvesting technology that can be placed inside plants and generates electricity from wind or precipitation. This device can generate enough electricity to power itself and the LED lights in windy or rainy weather. A study published Feb. 28 in the journal IEEE Robotics and Automation Letters describes this new device.
Fabian Meder is a researcher working on bio-inspired soft robots at the Italian Institute of Technology (IIT) in Genoa, Italy. He says a system that generates power from leaves could be particularly useful for remote environmental monitoring and agricultural applications where self-powered sensors are required to study plant health.
The device, developed by Meder et al., consists of an artificial leaf placed between the leaves of a real plant and with a silicon elastomer layer on the underside. The two surfaces come into contact and separate again as [the leaves] move in the wind, causing static charges on our device and the cuticle of the plant leaf. These charges occur in the inner cellular tissue of the plant, where they generate a current. We can capture this current by placing an electrode in plant tissue.
Similar methods are used by an existing array of energy harvesting devices built into plants to generate electricity from the wind, but this work team has gone a step further by developing a device that can also capture energy from raindrops.
The silicon elastomer layer on the underside of the artificial leaf is different from the fluorinated ethylene propylene (FEP) layer on the upper side of the artificial leaf to generate and collect static charge from the rustling of leaves. Electrodes placed in and on the artificial leaf connect when raindrops fall on this upper layer, charging the surface and forming a capacitor. The capacitive coupling between the electrodes changes as raindrops contract and spread over the leaf's surface, creating a current.
The ability to capture energy with varying degrees of wind and rain was tested by the researchers by placing the false leaf systems on the leaves of a living oleander plant. They discovered that a single drop of water can directly power 11 LED lights, producing voltage and current peaks of over 40 volts and 15 microamps.
The device is either a multifunctional energy harvester or a self-powered sensor, according to Barbara Mazzolai, director of IIT's Bio-inspired Soft Robotics Laboratory and assistant director of robotics, who was also involved in the study. “The results suggest that it is possible to harvest wind and rain energy separately or simultaneously with the device,” she says.
He points out that existing wind-only systems like this tend to generate less electricity when their surfaces are wet. However, the researchers claim that their new device can generate more electricity in humid environments, thanks to the top FEP layer that traps energy from rain.
Based on the findings of this study, the researchers think that design changes, such as materials and electrode shapes, could possibly further improve the performance of their artificial leaves.
According to Mazzolai, “We are examining possible markets and have filed a patent on the technique. But more work needs to be done before defining the final product. For example, we want to extensively test systems in environments with a wide variety of wind and rain conditions.
source: spectrum.ieee.org
Günceleme: 21/03/2023 20:53