Six EU gas grids have a target of 100% substitution of natural gas with renewable gas by 2050. This industry will start with biogas upgraded to biomethane. The biomethane resource and location of waste substrates (such as agricultural slurries, slaughterhouse waste, milk processing waste, and source separated household organic waste) were determined using the most recent spatially explicit data for Ireland. The total biomethane resource was estimated equivalent to: 7.6% of natural gas usage, 7% of energy in transport; 52% of the fuel usage in heavy goods vehicles in 2013. In terms of natural gas usage it corresponded to 26.5% of industrial gas use, and 52% of residential natural gas use. The resource as a source of thermal energy is equivalent to wood chips from 16.5% of arable land under short rotation coppice willow. Thematic maps illustrating the location of each resource were developed to highlight regions of significant biomethane production potential. The regions with the greatest resource of cattle slurry are located in the south and east of the country; sheep manure resources are concentrated on the western seaboard, while the largest biomethane resource from household organic waste is found in urban and city areas (63% of household organic waste biomethane resource). (C) 2016 Elsevier Ltd. All rights reserved.