Benthic Microbial Fuel Cells Engineered for High Power Density

Benthic microbial fuel cells are bio-electrochemical power sources that derive fuel from renewable detritus. They have the potential to be cost-effective, sustainable energy sources to power remote, widely distributed marine sensors and instruments for oceanographic, environmental and biological monitoring. Unfortunately, power densities so far demonstrated are insufficient to make these fuel cells practicable and cost-effective. Thus, the principal objective is to demonstrate the feasibility of developing high power density benthic fuel cells. This will be accomplished by selective preemptive colonization of electrodes with naturally-derived marine or sedimentary microbial populations that most effectively generate electrical current. Laboratory microbial fuel cells will be used to demonstrate that selective preemptive colonization can result in power densities exceeding 2.5 W/m2. Because efficient use of the available power is required, designs for a high-efficiency power conversion and management system will be developed. During Phase II, the microbiology, electrode, and system design of the benthic fuel cell will be optimized to further increase power density (> 4 W/m2). The long-term performance of a prototype benthic fuel cell device integrated with a marine sensor and telemetry system will be demonstrated in a field-trial.