How plant biology can revolutionize renewable energy

New research has shown that plants’ hydraulic systems generate continuous electrical potential synchronized with their circadian rhythms, creating innovative opportunities for sustainable energy production.

When plants draw water from their roots to nourish their stems and leaves, they create electrical potential that can be used as a renewable energy source. However, like all living things, plants are subject to circadian rhythm – a biological clock that operates through day and night cycles and influences biological processes. In plants, this circadian cycle involves the capture of light energy photosynthesis and absorbs water and nutrients from the soil during the day and slows down its growth processes at night.

Study observations about electrical potential in plants

In a new study published this week in Fluid physicspublished by AIP Publishing, scientists from the Indian Institute of Technology Kharagpur have detailed how biological processes create tension in plants and the impact of day and night cyclical changes on this tension.

“This streaming potential, which is essentially a consequence of the natural energy stored in the power plant, provides a renewable energy source that is continuous and can be sustainable over a long period of time,” said author Suman Chakraborty. “The question we wanted to answer was how much potential can it produce, and how does the plant’s biological clock affect the electrical potential?”

Methodology and discoveries

To find out, the authors inserted electrodes into the stems of water hyacinths and attached reservoirs of electrodes to pieces of lucky bamboo to study exactly how the electrical potential changes depending on the type of ions, their concentration and the pH of the fluid flowing through the plants.

“Our eureka moment came when our first experiments showed that it was possible to generate electricity in a cyclical rhythm and precisely link this circadian rhythm to the plant’s inherent rhythm,” Chakraborty said. “We could determine exactly how this is related to water transpiration and the ions that the plant transfers through rising sap.”

The study quantified the voltage response resulting from the movement of ions through plant pathways that are uniquely harmonized with the plant’s daily rhythm.

The potential for sustainable energy

The authors found that plants can actively regulate the flow of fluids or sap in synchronization with day and night cycles. They also found that the electric jetting potential increased as the ion concentration decreased or the pH in the fluid increased.

“Not only have we rediscovered the electrical rhythm of power plants by expressing it in terms of voltages and currents, but we have also provided insight into the potential of harvesting electricity from power plants in a sustainable manner, without impacting the environment and without disturbing the ecosystem,” Chakraborty said.

“The findings could help develop biomimetic, nature-inspired systems that can address the global energy crisis with an eco-friendly, sustainable solution in which planting trees not only alleviates the crises of climate change and deteriorating environmental quality, but also provides way to use electricity from it.”

Reference: “How does the circadian biological clock influence the electrokinetics of a living plant?” by Aniruddha Guha, Saumyadwip Bandyopadhyay, Chirodeep Bakli and Suman Chakraborty, May 28, 2024 Fluid physics.
DOI: 10.1063/5.0195088