It looks bad and smells terrible, but animal waste can fuel power stations and can even be used in your car.
Can excrement energy save the world?
It's not surprising that animal faeces can be turned into fuel. After all, oil can come from treating animal fats, and the world's primary energy source arises when geological processes compress and heat tiny creatures until they form petroleum and natural gas.
Methane is the main constituent of natural gas. It is a simple molecule of one carbon atom to four of hydrogen, produced when organic material decays in the absence of oxygen. It's highly flammable. Burning it creates carbon dioxide, water and, most importantly for our domestic boilers and electricity generators, heat.
But since burning natural gas produces carbon dioxide thereby contributing to climate change, sucking methane from the bowels of the earth just for a hot bath is not environmentally friendly and is growing less acceptable. Luckily, there is another place to find this valuable substance...
First published in BBC Focus Magazine
