How to get electricity from living plants!

One of the most important issues in our planet is the by-product of burning fossil fuels for energy. Since industrial time, humanity has relied heavily on fossil fuels, resulting in large amounts of carbon dioxide and other greenhouse gases released into the atmosphere, ultimately making our air unclean. Moreover, CO2 and other pollutants trap solar radiation within the earth’s atmosphere, causing a rise in global temperatures. Fossil fuels have also caused depleting ozone levels and poses a health problem.

Two other students and I participated in the Clean Tech Competition a couple months ago where we had to find a solution to an issue in the environment. It had to be written in the form of a research paper with designs and evidence. After thorough background research, we based our idea on the concept of plants generating electricity as a potential alternative to fossil fuel. We focused on three steps: materials selection, design creation, and a walkthrough of the experiment.

We began by understanding the importance of organic matter in this experiment. Plants excrete organic matter into the soil, which is then broken down by bacteria. During this breakdown process, electrons are being released as a waste product of the bacteria living around plant roots. It is possible to harvest those electrons using inert electrodes to turn them into electricity, without affecting the plant’s growth. Precious metals, mercury, and carbon are typically used as inert electrodes. So, according to our research, we chose zinc to be the anode and copper to be the cathode. As the electrons leave the anode and enter the cathode, we could then measure the amount of voltage using a multimeter, alligator clips, and wires. For the measurements of the objects and plants, we also used a ruler. Lastly, three aspects of consideration were taken into account when we chose an aloe vera plant to be the test subject of the experiment: easy embedding, availability, and perfect stem moisture content.

For the experiment, we used a design where the Allen key and penny are placed on opposite sides of the plant to avoid any interference. Then we connected them with the alligator clips and wires, which were then hooked up to the multimeter. After, different variables were adjusted like the amount of copper (pennies) or the angle of the object. This simple design allows it to be of low cost and be built easily from household materials. Not only that but this design could also be easily altered to generate more electricity by using a bigger plant allowing it to generate enough to run low electrical consumption devices.

Next, for the first trial we measured the depth of the copper by connecting the multimeter to the Allen key and penny using wires and placed them on opposite sides of the plants. We moved the penny deeper into the soil and recorded the results of how the voltage changed.

For the second trial, we tested the distance between the metals copper and zinc keeping all other conditions the same.

For the third trial, we tested the amount of copper by placing several pennies in the soil expanding the amount of cathode.

For the last trials, we tested the angle of the cathode by putting the penny at different angles to see if it affects the amount of voltage generated.

This model can have many implications, the most important of which is a low-budget alternative to burning biomass and fossil fuels. This product can have great uses like charging devices and powering light bulbs.