By JULIAN GAVAGHAN
Bacteria usually found orbiting high above the Earth have been found in a British river – and could be a new power source for the world. The mysterious organisms, found in the the mouth of the River Wear, in Sunderland, can generate electricity using a special battery called a microbial fuel cell.
The Bacillus stratosphericus – usually found 20 miles above the Earth – is believed to have been brought to the surface by atmospheric cycling, which causes evaporated water rise into the stratosphere and then fall again.
It is a particularly potent form of bacteria which can be used in a microbial fuel cell (MFC) to convert river waste into power and clean water. It had double the electricity generating potential of other bacteria and scientists from Newcastle University believe they could be harvested and used in the developing world to power appliances.
Inside an MFC, the organisms produce carbon dioxide, protons and electrons when kept in a solution without oxygen. Liberated electrons form a negatively charged anode while the protons create a positively charged cathode. This produces both charges necessary to produce an electric current.
Publishing their findings in the American Chemical Society’s Journal of Environmental Science and Technology, Grant Burgess, Professor of Marine Biotechnology at Newcastle University, said the research demonstrated the ‘potential power of the technique’. He said: ‘What we have done is deliberately manipulate the microbial mix to engineer a biofilm that is more efficient at generating electricity.
‘This is the first time individual microbes have been studied and selected in this way. ‘Finding B.stratosphericus was quite a surprise, but what it demonstrates is the potential of this technique for the future – there are billions of microbes out there with the potential to generate power.’
Prof Burgess said that, isolating 75 different species of bacteria from the River Wear, the team tested the power-generation of each one using a Microbial Fuel Cell (MFC).
By selecting the best species of bacteria, scientists were able to create an artificial biofilm, doubling the electrical output of the MFC from 105 watts per cubic metre to 200 watts per cubic metre. While still relatively low, this would be enough power to run an electric light and could provide a much-needed power source in parts of the world without electricity.