Bord Gáis Eireann Fellowship

Bord Gáis Eireann Fellowship
An evaluation of the logistics of the utilisation of compressed natural gas and compressed biomethane as a transport fuel in Ireland


Lead PI: Dr Jerry D Murphy

Researcher name: Beatrice Smyth

Duration of research: 2007-2010


Project description:


To date, much of the discussion in Ireland on biofuels for transport has focussed on liquid biofuels, such as biodiesel and bioethanol. However, there are limits on the quantity of land available for these crops and so also on the total energy output. Previous work by this research group has shown that the generation of biofuel from grass in the form of biomethane requires only a quarter of the land needed to produce the equivalent amount of biodiesel from rapeseed. In addition to this, there is significantly more land available for grass in Ireland, which has ten times more grassland than arable land. Biomethane can also be produced from wastes (such as cattle slurry or food and garden waste), which has the double benefit of requiring no land and providing an effective waste management strategy.


Compressed biomethane is almost identical to compressed natural gas, which is currently used as a transport fuel in many countries worldwide. A growing number of countries, such as Sweden and Austria, are also using compressed biomethane (either on its own or combined with natural gas) as a standard transport fuel.


The focus of the research is on the use of gas as a transport fuel, with particular emphasis on the use of grass to generate biomethane. Specific areas of research include the energy balance of grass biomethane; the logistics of a compressed natural gas (CNG) transport system in Ireland; the potential of residues to generate biogas; the food versus fuel debate in relation to grass biomethane; and the economics of the grass to biomethane system. Coming out of this work two papers, one on a full life cycle analysis of the energy balance of grass biomethane and the other on the potential of residues for biofuel production, have been accepted for publication.


Publications from project:


Peer review journal publications


  1. Smyth BM, Murphy JD, O'Brien CM. 2009. What is the energy balance of grass biomethane in Ireland and other temperate northern European climates? Renewable and Sustainable Energy Reviews, Vol 13(9), Dec 2009, pp 2349-2360. doi:10.1016/j.rser.2009.04.03.

  2. Singh A, Smyth BM, Murphy JD. 2009. A biofuel strategy for Ireland with an emphasis on production of biomethane and minimization of land take. Renewable and Sustainable Energy Reviews. doi:10.1016/j.rser.2009.07.004.



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