The continuous progress of bio-science has led to the discovery that bacteria can directly produce electricity by degrading organic substances dissolved in natural environments — seawater, rivers, lakes, municipal or agri-food wastewater, and soils contaminated by heavy metals or organics.
Microbial fuel cells (MFCs) are a new and exciting area of biotechnology, with operational and functional advantages over the technologies currently used to generate energy from organic substances. They convert the energy available in a bio-convertible substrate directly into electricity with the aid of micro-organisms.
MFCs operate efficiently at ambient — and even lower — temperatures, distinguishing them from most current bio-energy processes. An MFC does not require gas treatment because its off-gases are enriched in carbon dioxide and normally have no useful energy content. MFCs also have potential for widespread application in locations with no electrical infrastructure, and can expand the diversity of fuels used to meet energy needs.
A typical MFC consists of an anode compartment and a cathode compartment: in the anode compartment a substrate is oxidized by micro-organism activity, while in the cathode compartment an electron acceptor is reduced.
In situ continuous current production from marine floating microbial fuel cells.