Biobatteries “breathe” electrons
Scientists at Leti, a CEA Tech institute, recently proved that it is possible to produce electricity from marine sediments. They developed a benthic microbial fuel cell demonstrator system with the associated electronics that performed well enough to power devices like environmental sensors.
The benthic microbial fuel cell (BMFC) is a simple and non-polluting system that produces electricity from marine sediments, making it particularly well-suited for powering permanent ocean sensors. Researchers at Leti have made this concept a reality by developing an enhanced electronic interface capable of ensuring that the system can adapt to the very low and variable voltages and power produced.
The researchers' electronic interface, which was built using commercially-available circuits, achieved some very promising results. "We tested our demonstrator system in a saltwater environment and in the lab. It produced 0.1 watt per square meter of battery, which is enough to permanently and independently power devices like small water-temperature sensors," said a Leti representative.
The researchers' next step will be to try to develop their own electronics with an integrated circuit this time. The goal will be to reach two to three times greater energy yields for similar battery surfaces (around ten square centimeters). The system could potentially be used in a variety of ocean observation capacities, from natural geological risks to swimming water quality and waste treatment.