Lead researcher Bill Yen in the lab at Northwestern. (Photo credit: Bill Yen/Northwestern University) 
The clean fuel cell in the lab. (Photo credit: Bill Yen/Northwestern University) 
Working in the lab, lead researcher Bill Yen buries the fuel cell in soil. (Photo credit: Bill Yen/Northwestern University) 
The device’s 3D-printed cap sticks out of the ground. (Photo credit: Bill Yen/Northwestern University) 
The fuel cell, coated in dirt after being pulled from the ground. (Photo credit: Bill Yen/Northwestern University) 
This schematic shows an “exploded view” of the device. (Image credit: Bill Yen/Northwestern University)
Read the full story from Northwestern University.
A Northwestern University-led team of researchers has developed a new fuel cell that harvests energy from microbes living in dirt.
About the size of a standard paperback book, the completely soil-powered technology could fuel underground sensors used in precision agriculture and green infrastructure. This potentially could offer a sustainable, renewable alternative to batteries, which hold toxic, flammable chemicals that leach into the ground, are fraught with conflict-filled supply chains and contribute to the ever-growing problem of electronic waste.
To test the new fuel cell, the researchers used it to power sensors measuring soil moisture and detecting touch, a capability that could be valuable for tracking passing animals. To enable wireless communications, the researchers also equipped the soil-powered sensor with a tiny antenna to transmit data to a neighboring base station by reflecting existing radio frequency signals.
Not only did the fuel cell work in both wet and dry conditions, but its power also outlasted similar technologies by 120%.
The research was published Jan. 12 in the Proceedings of the Association for Computing Machinery on Interactive, Mobile, Wearable and Ubiquitous Technologies. The study authors also are releasing all designs, tutorials and simulation tools to the public, so others may use and build upon the research.
Environmental News Bits 