BioGas & biomethane

Why BioGas?

Biogas is an energy rich renewable gas containing a high percentage of methane (50-70%). It is produced in a process known as anaerobic digestion, where energy comprising organic material is transformed into an energy accessible gas. The production of biogas uses locally derived feedstock such as food waste, agricultural waste and energy crops that in turn create a local economy through the growing and supply of feedstock. The by-product formed is an organic fertiliser, which replaces artificial chemical fertilisers, that is returned to the land which helps protect waterways, promote organic growth and creates jobs, due to its handling.

Derived from renewable sources, Biogas is carbon neutral and in some cases carbon negative, and offers a mechanism not only for decarbonisation of Ireland’s national electricity grid but also Ireland’s gas system.

With Biogas, there are many more options for energy utilisation outside of electricity generation such as transport and heating. One such way is Biomethane which can be used for both transportation and heat.
Biogas contains 40-50% carbon dioxide. We can remove this carbon dioxide from biogas upgrading it to pure biomethane. We can use biomethane in a number of ways.

Key Outputs


A high quality eco fertiliser rich in nutrients that we apply to agricultural land displacing artificial fertiliser.


An energy rich gas, high in methane, that we use in a high efficiency CHP to generate electricity and heat.

GreenGas AD Plant is a state of the art farm based Anaerobic Digestion plant located outside Shanagolden in County Limerick. The biogas plant processes manure and slurry from local poultry and dairy farms as well as other imported feedstock. We convert the energy contained in these materials into a usable form of energy, such as electricity.

The biogas produced in the anaerobic digestion process is used as fuel in a high efficient Combined Heat and Power Engine (CHP) which produces electricity and heat. We use some of the electricity produced for onsite use with the majority exported to the national grid and the heat is used in both onsite and in the nearby poultry enterprise. The nutrient rich digestate is used on local farm land as a high quality eco fertiliser.


The simplest way is to use biomethane is to compress it, creating a fuel similar to Compressed Natural Gas (CNG) which is used to fuel buses and heavy goods vehicles. We can compress the gas further liquefying it making it more easily transportable and making it available to LPG customers.

By the addition of trace gases and odourising biomethane we have a renewable Natural Gas. Biomethane is the most efficient way of greening our natural gas grid which is 100% fossil fuel.

The greenhouse gas savings of biomethane fuelled vehicles can be significant. Methane fuelled vehicles can also have extremely low emissions of local pollutants, including NOx and particulates (PM2.5 and PM10) when compared to modern petrol and diesel vehicles.

Resources & Associations

Irish BioEnergy Association

View Ireland's renewable energy associations

bord gais energy

Flogas Enterprise


Clean Ireland Recycling

Team Limerick Cleanup

Universiy college dublin

University of Galway