Two of the key challenges facing us as a global community in the 21st century are climate
change & access to clean water. Population growth and increasing usage of water has resulted
in ever larger volumes of wastewater. Heightened public awareness & concerns over long
term environmental & health effects have resulted in increasingly tight discharge standards.
These twin drivers fuel the rise in energy required for treatment
One of the most energy intensive aspects of wastewater treatment is aeration for the aerobic
oxidation of organic compounds. Typically half the energy is used for aeration and a key byproduct
is a large amount of excess sludge. Treatment &disposal of this sludge is both costly
and generates further environmental concerns. The treatment of water is currently the 4th
largest sector for energy usage in the UK & global warming concerns mean that the industry
is under pressure to achieve higher water quality whilst reducing its carbon footprint
The generation of electricity from the organics in wastewater has been acknowledged fact for
many years and the potential benefits have been recognised by the EC (Future Brief 2013)
“Globally billions of Euros are spent treating trillions of litres of wastewater every year,
consuming substantial amounts of energy However, this wastewater could act as a renewable
resource, saving significant quantities of energy and money, as it contains organic pollutants
which can be used to produce electricity”
Devices that can convert organic compounds directly to electricity are known as microbial
fuel cells (MFCs) and combine biological & electrochemical processes. Whilst significant
research has been undertaken into the potential of MFCs as a source of renewable energy, no
large scale plants have been installed & the research is limited to the laboratory. Existing
designs are complex and costly, so this project aims to investigate innovations that will
simplify the design to allow low cost scale up of these device