Posted on 01/18/2024 7:30:19 AM PST by Red Badger
A team of researchers from Northwestern University says they have developed a cutting-edge, power-generating fuel cell that runs on dirt by capturing the electricity generated by microbes that live in soil. Previous attempts at microbial fuel cells (MFCs) have been stymied by low power outputs and unreliable performance, but the Northwestern system seems to have conquered these issues.
The inventors of the dirt-powered fuel cell believe it can revolutionize precision farming, while lessening the use of batteries that often contain toxic chemicals and rely on lithium and heavy metals that are a limited resource and can damage crops and soil. They are also making their design open source so farmers everywhere can take advantage of the breakthrough device
INSTEAD OF BUILDING A BETTER BATTERY, RESEARCHERS DECIDED TO TRY REPLACING IT
“The number of devices in the Internet of Things (IoT) is constantly growing,” said Northwestern alumnus Bill Yen, who led the effort to create a viable MFC. “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.”
This need is especially high in the agricultural industries, where minute sensors covering numerous acres of land require only small amounts of reliable energy to significantly increase crop yields. Unfortunately, farmers are unable to tend to so many devices accurately, especially if they are unable to generate their own power and require constant replacement of batteries.
“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 are also a challenge, Yen explained, as they ultimately 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,” he quipped.
To address this problem in a practical yet innovative way, Yen and his team decided to look at devices that could generate reliable power on the spot while also requiring little to no maintenance. The solution turned out to be devices that utilize the electrical generation properties of microbes found right in the dirt.
Image of a novel fuel cell that runs on dirt designed by Northwestern University researchers. Image Credit: Bill Yen/Northwestern University.
MFCS USED THE POWER OF MICROBES LIVING IN THE DIRT TO GENERATE RELIABLE ELECTRICITY
In their published study, the Northwestern researchers point out that creating a fuel cell that runs on dirt is not a new idea. However, developing an MFC that is reliable and can work under both wet and dry conditions has stymied researchers for decades. That’s because MFCs need to stay hydrated and oxygenated to work properly.
“Although MFCs have existed as a concept for more than a century, their unreliable performance and low output power have stymied efforts to make practical use of them, especially in low-moisture conditions,” Yen explained.
Still, the idea of a working MFC seemed to resolve a lot of the issues around sensors powered by batteries and solar panels. They are also attractive because their primary power source, the activity of microbes, is found pretty much anywhere one finds dirt.
“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.”
Like a battery, an MFC contains an anode, a cathode, and an electrolyte. According to the press release announcing the Northwestern team’s work, “MFCs harvest electricity from bacteria that naturally donate electrons to nearby conductors.” This flow of electrons from the anode to the cathode generates an electric circuit that can be captured and used in electronic devices.
GEOMETRY THE KEY TO VIABLE FUEL CELL THAT RUNS ON DIRT
To develop an MFC that could work in wet and dry conditions while still creating reliable, useable power, the Northwestern researchers built and tested four different designs. After nine months of testing and evaluation, they settled on one particular model that they then tested in an outdoor garden. As hoped, the device proved equally reliable in both wet and dry conditions and functioned well enough to power the type of soil sensors farmers are now using to maximize crop yields.
The key, the researchers explain, was in the device’s geometry. Instead of the typical MFC setup where the anode and cathode are parallel to each other, the Northwestern MFC involves a perpendicular design. This small but substantial change allowed the team to place the power-generating elements of the MFC in the dirt while keeping a cap above ground to maintain the oxygenation needed for electricity generation.
The fuel cell’s 3D-printed cap peeks above the ground. The cap keeps debris out of the device while enabling airflow. CREDIT: Bill Yen/Northwestern University
“Although the entire device is buried, the vertical design ensures that the top end is flush with the ground’s surface,” they explain. “A 3D-printed cap rests on top of the device to prevent debris from falling inside. And a hole on top and an empty air chamber running alongside the cathode enable consistent airflow.”
They also coated their MFC with a waterproof material so it can breathe during a flood. The result was a working MFC that lasted 1205 longer than similar designs and generated 68 times as much power as needed to run its sensor. The researchers say that this surplus of electricity can run a small, wireless radio antenna embedded in the sensor that can communicate its readings to the farmers a long distance away.
FUEL CELL THAT RUNS ON DIRT IS AVAILABLE TO EVERYONE
The Northwestern team says that all of the materials and components in their MFC are readily available at a local hardware store. This includes the carbon felt used in the cathode that captures the electrons generated by the microbes.
The team also says they are making the designs, tutorials, and simulation tools available to everyone in hopes that farmers can build their own fuel cell that runs on dirt and inventors can work to improve them. That information can be found in their published work, which appears in the January 12th edition of Proceedings of the ACM on Interactive Mobile Wearable and Ubiquitous Technologies.
“With the COVID-19 pandemic, we all became familiar with how a crisis can disrupt the global supply chain for electronics,” said study co-author Josiah Hester, a former Northwestern faculty member who is now at the Georgia Institute of Technology. “We want to build devices that use local supply chains and low-cost materials so that computing is accessible for all communities.”
Think of these poor microbes, what happens to the microbes ?
MLM
Isn’t it more efficient to create farms of unconscious people and plug them into the grid?
Yep. Fits in a backpack and powers your watch.
“NORTHWESTERN RESEARCHERS INVENT AN INCREDIBLE POWER-GENERATING FUEL CELL THAT RUNS ON DIR”
Awesome! My lot just happens to contain a YUGE amount of dirt! AND, if i run out, it’s easy enough to get plenty more!
gotta love the freebee harbor freight voltmeter!
If they could find a way to do this with processed trash waste from compost-producing plants many county waste handling departments have gotten taxpayers to fund that would be a good thing, I guess.
EUREKA! I've got the solution! We'll bury a fuel cell IN the dirt.
I’m waiting for one that’ll run on cat poop….
“limited applicability.”
Farms are going high-tech and there is a growing number of remote sensors. Maybe this could make enough power to run low-power remote sensors and RF communications.
The point is lost on you. Researchers doing pure research are many times too myopic to see the potential in something they’ve invented. They are employed by a company to work as required.
You’ve just shown that inventions and byproducts of inventions were capitalized on by people other than the researcher. That was my point.
Or, another earth-shattering technological breakthrough destined to save the world multiple trillions in energy costs, never to be heard of again.
Have you been a prissy libtard since you voted for biden or have you been one your entire life?
Isn’t that where ze bugs live? Gonna have to pick one or the other.
I have half a dozen free ones from Harbor Freight... some are yellow and some are red. A couple of them quit working after a while but it is nice to have them in the cars and trucks, the workshop, or just by the breaker box.
I paid $80 for my first digital multimeter from Radio Shack in the 1970s. It still works, but the display is now all screwed up.
my first voltmeter was a radioshack analog one with the electromechanical needle ... it probably still worked, but got tossed during a cleanout a few months ago ... have several of the freebee harbor freight ones and a couple of really good ones like Amprobe ...
I don’t have any premium multimeters, but I have quite a few specialty meters.
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