Energy study eyes 'cow power'
Updated on 24 July 2008
"Cow power" generated from livestock manure could provide up to 3% of North America's electricity needs and lead to a significant cut in greenhouse gas emissions, scientists have claimed.
A study found strong evidence that "where there's muck there's energy" - and lots of it.
The research was the first attempt to quantify the amount of renewable energy obtainable from herds of cows and other livestock on a national scale.
Livestock manure left to decompose naturally produces two potent greenhouse gases, methane and nitrous oxide. Methane warms the atmosphere 21 times more effectively than carbon dioxide, while nitrous oxide is 310 times more powerful.
But if manure is anaerobically digested - a fermentation process similar to the one that creates compost - it is converted into energy-rich biogas which can drive turbines to produce electricity.
Hundreds of millions of livestock animals are reared in the United States. Using their waste for power generation could potentially produce about 100 billion kilowatt hours of electricity, the experts predict. That is enough to power millions of homes and offices.
Such a system would also reduce greenhouse gas emissions by 99 million metric tonnes, it is claimed. About 4% of US greenhouse gas emissions from electricity production would be wiped out.
Methane, which can be used as fuel, is the main component of biogas. Although biogas-burning plants would emit some carbon dioxide, the amount is much less than from burning coal.
Dr Michael Webber and Amanda Cuellar, from the University of Texas at Austin, reported their findings in the journal Environment Research Letters.
They wrote: "In light of the criticism that has been levelled against biofuels, biogas production from manure has the less controversial benefit of reusing an existing waste source and has the potential to improve the environment."
These news feeds are provided by an independent third party and Channel 4 is not responsible or liable to you for the same.
