Scientists develop dirt-powered fuel cell that could replace batteries
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Scientists develop dirt-powered fuel cell that could replace batteries
This new tech turns soil microbes into a steady power source for smart sensors.
Date:
April 19, 2026
Source:
Northwestern University
Summary:
Scientists have developed a fuel cell that uses microbes in soil to produce electricity. The device can power underground sensors for tasks like monitoring moisture or detecting touch, without needing batteries or solar panels. It works in both dry and wet conditions and even lasts longer than similar technologies. This could pave the way for sustainable, low-maintenance sensors in farming and environmental monitoring.
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The fuel cell's 3D printed cap peeks above the ground. The cap keeps debris out of the device while enabling air flow. Credit: Bill Yen/Northwestern University
Researchers led by Northwestern University have developed a fuel cell that generates electricity using microbes naturally found in soil. The device, roughly the size of a paperback book, produces small amounts of power by capturing energy released as these microorganisms break down organic material in dirt.
This soil-powered system is designed to run underground sensors used in precision agriculture and environmental monitoring. It offers a potential alternative to traditional batteries, which contain toxic and flammable materials, rely on complex global supply chains, and contribute to growing electronic waste.
Powering Sensors Without Batteries
To demonstrate its capabilities, the team used the fuel cell to operate sensors that measure soil moisture and detect touch. This touch-sensing ability could help monitor wildlife movement, such as animals passing through a field. The system also includes a small antenna that sends data wirelessly by reflecting existing radio frequency signals, which keeps energy use extremely low.
The device proved reliable across a wide range of conditions. It functioned in both dry soil and flooded environments, and it produced more sustained power than similar systems, lasting about 120% longer.
The study was published in the Proceedings of the Association for Computing Machinery on Interactive, Mobile, Wearable and Ubiquitous Technologies. The researchers also released their designs, tutorials and simulation tools publicly so others can build on the work.
Why Soil Microbes Matter for the Internet of Things
"The number of devices in the Internet of Things (IoT) is constantly growing," said Northwestern alumnus Bill Yen, who led the work. "If we imagine a future with trillions of these devices, we cannot build every one of them out of lithium, heavy metals and toxins that are dangerous to the environment. We need to find alternatives that can provide low amounts of energy to power a decentralized network of devices. In a search for solutions, we looked to soil microbial fuel cells, which use special microbes to break down soil and use that low amount of energy to power sensors. As long as there is organic carbon in the soil for the microbes to break down, the fuel cell can potentially last forever."
Microbial fuel cells, often called MFCs, work somewhat like a battery. They include an anode, cathode and electrolyte, but instead of chemical reactions, they rely on bacteria that naturally release electrons. When these electrons move through the system, they create an electric current.
"These microbes are ubiquitous; they already live in soil everywhere," said Northwestern's George Wells, a senior author on the study. "We can use very simple engineered systems to capture their electricity. We're not going to power entire cities with this energy. But we can capture minute amounts of energy to fuel practical, low-power applications."
Challenges With Solar and Battery-Powered Sensors
Precision agriculture depends on large networks of sensors that continuously track soil conditions such as moisture, nutrients and contaminants. These data help farmers make more informed decisions and improve crop yields.
But powering those sensors is a major challenge. Batteries eventually run out and must be replaced, which is impractical across large farms. Solar panels can also be unreliable because they become dirty, require sunlight and take up space.
"If you want to put a sensor out in the wild, in a farm or in a wetland, you are constrained to putting a battery in it or harvesting solar energy," Yen said. "Solar panels don't work well in dirty environments because they get covered with dirt, do not work when the sun isn't out and take up a lot of space. Batteries also are challenging because they run out of power. Farmers are not going to go around a 100-acre farm to regularly swap out batteries or dust off solar panels."
The researchers instead focused on harvesting energy directly from the soil itself, turning the environment into the power source.
Why Earlier Microbial Fuel Cells F