Lowering our carbon footprint – one step at a time

One particularly impressive highlight gleaned from a review of the Teagasc National Farm Survey 2024 Sustainability Report, featured the strides that have been made in lowering carbon input per kilogramme of output across all agricultural enterprises. The standout figure is that greenhouse gas (GHG) emissions fell by 0.25t/hectare (ha) compared to the  2023 figure.
Some of the sectors have made more spectacular improvements than others, and some reductions have been more consistent across recent years, but, by any objective assessment, notable improvements are being made and built into our food production systems. The standard for carbon measurements is the CO₂   equivalent per hectare (CO₂  eq/ha). That measurement provides a common means of comparing static, reducing or increasing carbon usage from year to year. Looking across the six years up to and including 2024, the trends have been clear.

Dairy step-change

Apart from 2022, which showed a marginal increase for exceptional reasons, the trend in milk production has moved from static in the early years of 2019 to 2021 to significant GHG reductions for 2023 and 2024, when CO₂ eq/ha was 8.6t CO₂ eq/kg FPCM (fat and protein corrected milk) has reduced from 0.86kg in 2019 to 0.83kg last year. Further measurements using financial parameters found equally strong developments. The CO₂ eq/€ of output last year was 1.8kg. This is a reduction from 2.7kg five years previously. Moving on to other GHG emissions measurements, the nitrogen (N) balance , measured in kilogrammes per hectare (kg/ha), reduced from 179.4kg in 2019 to 165kg in 2024, although that figure was an increase on the previous 12-month period but the trend is downward. In terms of ammonia (NH₃ kg/ha) in 2024 that was 43.3kg compared to 50.3kg in 2019.

The hoofprint

Moving across to cattle production, the statistics also reveal clear progress being made in improving environmental sustainability. While being in no way spectacular, it is the overall trend that is important. Here, CO₂ eq/ha last year was 4t, a decline of 0.2t on the figure five years previously. The CO₂ eq/kg of liveweight also decreased from 11.2kg in 2019 to 10.3kg in 2024. There were bumps in the figures across the six-year period but, again, the trend is clearly downward. The most spectacular figure in terms of continuous reductions measured was in the CO₂ per euro of output, which showed year-on-year reductions from the baseline 2019 figure of 5.1kg, coming down to 4.8kg the following year, again reducing by 0.7kg in 2021, followed by reductions of 0.8kg, and 0.7kg, to deliver a CO₂ per euro of output of 2.4kg for 2024. Ammonia, NH₃ kg/ha, over the six years also reduced, from 23.3kg to 21.1kg in 2024. The nitrogen (N ) balance, while hiccupping along the way, ended up with a reduction from 59.2kg in 2019 to 54.6kg in 2024. That represents a reduction of 4.6kg from the baseline year.

Innovation driving down emissions

So, how and where are the incremental improvements in carbon input reductions being achieved? Adoption of novel technologies are central to success in this regard. The increase, for instance, in the use of protected urea as the go-to N input of choice has been quite remarkable, most especially on milk-production farms. The Teagasc sustainability report confirms the high adoption rate. Moving from a negligible figure five years ago, over 40 per cent of total chemical N was applied in the form of protected urea last year, with anecdotal evidence that the percentage has well passed 50 per cent in the current year. As its use becomes increasingly obligatory across most farms from 2026 onwards, the benefits of using protected urea both as an economically viable alternative to CAN or conventional urea, as well as a major driver in reducing GHG will continue to be seen in the years ahead.
Likewise, the adoption of low emission slurry spreading (LESS) technologies has been nothing short of spectacular. At this stage, driven by regulatory compulsion as well as generous government financial supports, 85 per cent of slurry produced on dairy farms was spread using LESS in 2024. By the end of this year, practically all dairy-produced slurry will be utilised using LESS technologies, due both to obligatory regulation and the retirement of ageing conventional spreading equipment. The adoption of LESS on drystock farms has been significantly slower, but rising, year on year, as more farms gear up over time, and contractor services renew their slurry spreading equipment with LESS machines.

Tillage efficiency

Our tillage farms are the stand-out sector in terms of low carbon footprint. The CO₂  eq/ha figures continue to reduce year on year and are consistent with the general acceptance that tillage farms are among the most economically efficient across all sectors. Sheep farms, while generally operating as relatively low carbon emitters, are challenged on a number of other sustainability fronts, including a reducing national flock, a deteriorating farmer-age profile, and low average productivity.

Additional data required

The National Farm Survey is delivering enormous amounts of data across the fundamental sustainability parameters including economic, environmental, and social, as well as the recently added innovation statistics. In discussing the environmental figures in this article, note should be taken of the survey compilers’ admission that further developments, in terms of measuring biodiversity, for instance, are contingent on more data sharing. Measures of biodiversity, as the report states, especially those designed to accurately ascertain small changes over time on individual farms, are ‘technically challenging to implement and require considerable human, financial and data collecting and collating resources’. Teagasc does affirm the intention to ‘include a measure of biodiversity quantity in future sustainability reports, as soon as the necessary relevant scientific work needed to establish indicators and consistently collect the related data has concluded’.
This may take on an added urgency in the coming years as data around habitats and biodiversity health are likely to become more central to maintaining critical permissions to farm, none more so than the nitrates derogation, provided further extension negotiations are successful at this time.

Measurable progress

In general terms, Irish agriculture is making progress in reducing its carbon footprint. However, it is unclear if sufficient progress will be made to deliver on its 2030 emissions targets is unclear. What is, perhaps, more important is that definable, measurable progress is being made, with many of the driving factors delivering incremental improvements, year-on-year. Further novel technologies, still to be perfected for practical farm use, should lower our carbon footprint even further in the coming years. That Irish agriculture is far ahead of most European farm sectors in its progress and certifiable measurement of that progress, is of limited value, but is true, nonetheless.