RedHScience

"Bioenergy Applications"

Publication Date: 27 January 2025

MICROBIAL FUEL CELLS (MFCs)

Bioenergy is generally a field concerned with the production, transformation, and utilization of energy in biological systems. It can be considered in two main contexts:

Biological Energy Metabolism:

The production of ATP in living organisms through biochemical processes such as cellular respiration (glycolysis, Krebs cycle, oxidative phosphorylation) and photosynthesis.

Energy Production from Biomass:

Obtaining biofuels (biodiesel, bioethanol, biogas) from organic materials such as plant and animal waste. This is important in terms of renewable energy production.

But instead of these contexts, we will focus more on technologies that enable direct energy generation from living organisms, such as biofuel production or Microbial Fuel Cells.

MFCs (Microbial Fuel Cells):

Microbial fuel cells (MFCs) are non-combustible devices that provide electrical energy by using microorganisms as biocatalysts and organic matter as substrates—or food for the microorganisms. As these live microbes metabolize the substrate, chemical energy is converted into usable electrical energy. MFCs can utilize waste materials such as rumen fluid¹ as a source of biocatalysts and agricultural by-products such as manure, corn stover, or used straw bedding as substrates. In this way, MFCs are inexpensive to construct since they rely on abundantly produced materials that are traditionally considered waste.

Progress made over the past two decades has significantly increased the power output and conversion efficiency of MFCs. As a result, MFCs can be widely applied in wastewater treatment, powering marine electronic devices in remote locations, and as biological sensors².

Source: https://fabe.osu.edu/mfcfacts

¹ Rumen fluid is the liquid found in the rumen, the first compartment of the stomach of ruminant animals (e.g., cows, sheep, goats). It plays an important role in digestion and is rich in microorganisms (bacteria, protozoa, and fungi) that help the animal digest complex carbohydrates such as cellulose.

² Biosensors are devices that combine a biological component (enzyme, antibody, DNA, cell, etc.) with a physical detector. They detect a specific biochemical or biological event and convert it into an electrical or optical signal.