A win-win solution for farming, for our Kyoto targets, and for the environment

Date released: Feb 02 2005

An underdeveloped Irish industry has the potential to be a win-win solution for farming, for our Kyoto targets, and for the environment according to the Environmental Protection Agency (EPA) in a discussion paper on “centralised anaerobic digestion” released today.

“Anaerobic digestion is a natural process of decomposition and decay by which organic matter is broken down to its simpler chemical components.  Centralising such a process offers solutions to many agricultural, energy and environmental challenges facing Ireland currently”, said Dr John Curtis, EPA Economist.

The main benefits from centralised anaerobic digestion are:

- Ireland would be less dependent on electricity from fossil fuels by using energy generated by anaerobic digestion. Reductions in carbon dioxide emissions will contribute to our Kyoto Protocol targets.

- Groundwater protection will be enhanced: After animal slurries have been processed by anaerobic digestion they are less polluting and have an improved fertiliser value.   

- As a form of renewable energy, anaerobic digestion can make a significant contribution to Ireland’s target under the EU Renewable Energy Directive.  

- Return on investment for agricultural waste management: Compliance with the Nitrates Directive will cost up to €1 billion, as farmers will be required to invest in additional slurry storage capacity.  New storage capacity combined with anaerobic digestion will generate a return on such an investment through biogas generation and electricity sales to the national grid.

The costs and benefits of developing centralised anaerobic digestion in Ireland are outlined in the discussion paper.  

The EPA hopes that the paper will act as a catalyst for a discussion by interested parties on the issue.  If a consensus can be reached then the implementation of some incentives could make anaerobic digestion of organic wastes in Ireland a viable business option.


Notes for Editor:

After animal slurries have been processed by anaerobic digestion they have:

  • Less pollution potential - Tests of animal slurries from pilot and farm scale digesters show a reduction of 55% of BOD5 for cattle slurry, 75% for pig slurry and 80% for poultry litter.
  • Less odour - by as much as 80%.   
  • Better quality fertiliser – anaerobic digestion increases the proportion of nutrients immediately available for uptake by plants and provide a more balanced mixture fertiliser for agricultural application. 

Renewable Energy Directive:  Ireland must increase electricity produced from renewable energy sources to greater than 13.2% by 2010.  Energy from anaerobic digester plants is constant and can be guaranteed.  

Anaerobic Digestion: The anaerobic process can be used to turn residues from livestock farming, food processing industries, waste water treatment sludge, water treatment plant sludge among other organic wastes into biogas.  The biogas can be used to generate heat and/or electricity.  It also produces fibre which can be used as a soil conditioner and liquor, which can be used as a liquid fertiliser.