Interestingly the feedlots are mainly under the ownership of of the main beef processors who use them as a tool to manipulate the market ie in times of scarcity they introduce feedlot cattle to take up slack and drive prices down .As I recall around 10% of the total national emission come from two facilities on the shannon estuary - Moneypoint and the Rusal plant at Aughinish.
Replacing the power generated in the former and shuttering a profitable private enterprise in the case of the latter might not be easy.
But for over a 1/3 of the total 30% reduction commitment it might be a quicker win than changing the transport network entirely or in 10 years eliminating the one sustainable ( economically) industry based on natural resources .
That being said there is a conversation to be had on the long term direction of agriculture in Ireland. I read surprisingly on twitter recently of the massive growth in herds that are held in high intensity feedlots. this seems completely "off brand" with what Irish produced food should be trying to do. And , in context of this topic, a retrograde step to produce a lower margin product.
Plus in the very long term , and I am sure far smarter guys than me or any of the frauds masquerading in economists in the Irish media and NGO sector can run an estimate, there is a question of whether demographic growth & expansion of consumption in developing nations can , or to what extent will, forestall the impact of an inevitable long term decline in the per capita consumption of meat & dairy in the developed world.
Farming may have questions to answer on emissions but if govt policy was up to date the agri sector could make a contribution via forestry , biogas , peatland carbon sinks, wind farms etc but unfortunately our govt lags behind our European counterparts in essentially having no strategy on carbon credits .