“All the World's Cows on Treadmills Could Power Six Percent of Earth” is not the kind of headline you see every day - but one that no doubt caught a few eyes when Gizmodo.com published it recently.
The story is about a Northern Irish farmer, William Taylor, who gives his cows exercise in the barnyard while helping to drive a 2kW generator - apparently enough to power four milking machines.
As for where the ‘six percent of Earth’ figure derives from, it’s something of a back-of-an-envelope calculation based on cows walking up to eight hours a day when in fields, multiplied by the energy generated by Mr Taylor’s herd.
If this brainwave doesn’t seem to have taken off more widely, perhaps the animals’ excrement might be what our energy future is made of? Scientists at the University of East Anglia (UEA) might be starting to think so, after making some tentative steps towards creating a battery from the bacteria found in poo.
Such bacteria take in iron minerals and release a small electrical charge, which has resulted in inevitable headlines about the potential for this process to eventually power our energy-hungry gadgets. Professor Julea Butt from UAE is less specific, but believes this could be a practical outcome to her team’s work:
"This is an exciting advance in our understanding of how some bacterial species move electrons from the inside to the outside of a cell and helps us understand their behaviour as robust electron transfer modules. We hope that understanding how this natural process works will inspire the design of bespoke proteins which will underpin microbial fuel cells for sustainable energy production."
Exploiting biochemical processes is also the focus of a Dutch company, Plant-e, which hopes to use the electrons and protons passed out via the breakdown of sugars from photosynthesis. The results is a working ‘plant power’ prototype that powers 300 streetlights in Amsterdam.
Certainly the idea of modules of growing plants wired up for our municipal energy needs is somewhat out of the ordinary - but it’s also quite a pleasant concept to imagine coming into wider use. With a large-scale model in the pipeline, it seems this has more chance of a mainstream breakthrough than relying on cows to do their bit.