In a groundbreaking development, researchers propose a novel method called "electro-agriculture," which could redefine the way food is produced by eliminating the need for sunlight. This innovation, detailed in a recent paper published in Joule, could lead to food production systems that consume significantly less land- by an estimated 94%- and operate within controlled environments, potentially enabling agriculture in diverse settings, including space.
Potential of Electro-Agriculture and Solar-Powered Food Production
Current food production relies heavily on photosynthesis, a process that, despite its central role in supporting life on Earth, only converts about 1% of the sunlight absorbed by plants into usable chemical energy. The bioengineers behind electro-agriculture aim to replace this process with a solar-powered chemical reaction. This method would convert carbon dioxide (CO₂) into an organic molecule known as acetate, which genetically engineered plants could utilize as an energy source.
If implemented broadly, electro-agriculture could drastically reduce agricultural land use, making vertical farms and indoor agriculture more viable. Bioengineer Robert Jinkerson from the University of California, Riverside, envisions agriculture that is "decoupled from nature," operating in controlled environments where plants are no longer dependent on sunlight.
Buildings equipped with solar panels would capture sunlight to power the reaction, enabling CO₂ and water to produce acetate—a compound similar to acetic acid, the main component in vinegar. This acetate would then be used as a nutrient source for hydroponically grown crops, as well as for other food organisms like mushrooms, yeast, and algae.
The method also has the potential to outpace photosynthesis in efficiency. According to Feng Jiao, an electrochemist at Washington University in St. Louis, electro-agriculture currently achieves about 4% efficiency, quadruple that of natural photosynthesis. This greater efficiency means a smaller carbon footprint, positioning electro-agriculture as an eco-friendly alternative to conventional methods.
To enable plants to utilize acetate, the researchers are focusing on reactivating a metabolic pathway present in germinating plants that allows them to use stored food for energy. This pathway, which plants typically switch off once photosynthesis begins, would allow adult plants to use acetate as a carbon source instead of sunlight. Jinkerson likens this metabolic reawakening to a process similar to how humans often lose the ability to digest lactose as they age. Initially, the team is working with crops like tomatoes and lettuce, with plans to expand to high-calorie crops such as cassava, sweet potatoes, and grains.
At present, engineered plants can use acetate as a supplement to photosynthesis. The goal, however, is to develop plants capable of relying solely on acetate for energy, thus requiring no light at all. While this goal remains in the experimental phase, Jinkerson points out that non-plant food sources like mushrooms, yeast, and algae can already be produced this way, suggesting that these applications could be commercialized sooner.
The research team also plans to enhance the efficiency and cost-effectiveness of acetate production. Jiao notes that these early steps hold promise for greater efficiency and lower costs in the near future, potentially advancing electro-agriculture from research to practical applications.
This innovative approach to food production not only has implications for terrestrial farming but could also be a pivotal solution for agriculture in space, where resources and sunlight are limited. Electro-agriculture thus represents a forward-thinking step in optimizing food production for sustainability, land conservation, and environmental resilience.
(Source: Cell Press)
