Sir, – Gas Networks Ireland published a valuable report this month on the potential of biomethane which deserves more publicity. It indicates that one of these plants sized to produce 40-55 Gwh (gigawatt hours) in annual biomethane production would cost €15 million to construct.
The report suggests connecting them into the existing gas network, but in locations remote from an existing pipeline they could also generate electricity to feed into the national grid. The feedstock can consist of slurry, and other organic waste including municipal waste. Teagasc canvassed for expressions of interest in 2022 and received an encouraging 167 responses from prospective producers. Nutrients such as nitrates are converted by the process to minerals, and the residue from the process, the “digestate”, contains a higher concentration of plant-available nitrogen and phosphorus than the original slurry, and is a valuable fertiliser. The higher carbon content of the residue also improves the soil. It would appear to be a win-win situation that deserves Government support. – Yours, etc,