Scientists at the Electric Power Research Institute (EPRI) in the USA have developed a genetically engineered bacteria that can decrease the corrosion rate in the metals used in power plants.
Aerobic bacteria have been engineered that can cause a 35-fold decrease in the corrosion rate of mild steel and also significant decreases in aluminium and copper corrosion rates by consuming the oxygen that would normally oxidise the metal. The bacteria also deter the harmful bacteria from thriving.
When exposed to process water, metal surfaces in power plants are colonised by microbes which then merge to form a `biofilm`. The bacteria in these biofilms are sulphate-reducing and can cause pitting corrosion of most alloys as well as stainless steel and aluminium.
Corrosion costs the US electric power industry an estimated $5-10 billion each year.
Testing with the engineered bacteria in power plants will begin shortly.