Comprendre les enjeux de l'agriculture

A new startup, Bactery, based at the University of Bath in the UK, has created a self-recharging battery when placed in soil. Bacterial batteries, or bio-batteries, convert the chemical energy produced by bacteria into electricity. The working principle relies on biochemical reactions where bacteria release electrons. This revolutionary device can provide agriculture with a sustainable and renewable energy source, unlike traditional batteries that operate based on electrochemical reactions.

Traditional methods of supplying energy to farms, such as obstructive cables, single-use chemical batteries, and solar panels, depend on weather conditions.

Bacterial batteries operate through the phenomenon of electrochemical bioproduction. The bacteria present in these devices convert organic compounds into electrical energy, producing a continuous current. At the core of this process are anaerobic bacteria such as Geobacter and Shewanella, capable of transferring electrons to electrodes to create an electric current. This innovative electrochemical reaction is key to generating electricity with bacterial batteries.

Rural 21 explains the operating principle of the battery developed by Bactery: “Bactery’s technology relies on soil microbial fuel cells (SMFC) that harness energy from the metabolic activity of specific microorganisms known as electrogens, naturally present in the soil. Electrogens have the unique ability to generate electrons when consuming organic compounds. These electrons are ‘captured’ by the SMFC and are forced to circulate in an external circuit, thus producing electricity.”

Bacterial batteries have a wide range of applications, from powering small electronic devices to more complex systems such as wastewater treatment plants and environmental sensors. However, currently, bacterial batteries are primarily used in small-scale applications such as wireless sensors (Internet of Things). While bacterial batteries offer the advantage of producing energy sustainably and contribute to reducing agriculture’s carbon footprint, their energy yields are still relatively low. Nevertheless, notable progress is being made to make microbial batteries more efficient and less expensive.

Research focuses first on optimizing the components of the device, including electrodes and bacterial strains. Ultimately, these new batteries are expected to play an increasing role in the global energy landscape.

Bactery’s batteries have a lifespan of over 25 years at a projected cost of 25 pounds sterling per unit and require no maintenance. According to Rural 21, they can be installed and forgotten. Bactery has developed a way to efficiently increase and maintain electricity production through innovative designs and customized energy harvesting strategies tailored to the biological processes of each soil. Bactery will spend the next twelve months improving its prototypes before moving to small-scale production, with commercialization planned for 2026.


For more information: The websites of Rural 21 and Bactery