The work of AgResearch in New Zealand

AgResearch is a major New Zealand scientific research organisation which has been involved with Life Cycle Assessment (LCA) for over twenty years. In particular, the organisation has developed techniques which focus on the environmental impact of dairy production under the New Zealand system. Dairy companies like Fonterra have commissioned work which they are now using on farm to reduce carbon emissions. 

Senior scientist Andre Mazetto has used the analogy of storytelling when describing AgResearch’s LCA research:

“The people that work with LCA are the storytellers, and the food product is the main character. We need to understand where the product comes from, how it is produced, the main inputs for the production, how it is used, how it is distributed etc. This way, we can tell the story, and based on all this information, we calculate the product's environmental burdens, such as the carbon footprint.”[1]

Mazetto and his colleagues have been extensively involved in LCA research within the dairy industry. In a review paper [2] published in the Journal of Dairy Science they comment on the inconsistencies and variation when LCA techniques are applied to dairy production. Remarking that the complexity of LCA leads to these inconsistencies, their work went on to recalculate the data from 21 different studies from 19 countries and so allow accurate comparisons between different production systems to be made. The authors assess the complexities of comparing results which include differing boundaries, differing units of calculation and the confusion introduced by differing global warming metrics. All the papers included in the study went through a filtration process so that data could be compared and apples were eventually being compared with apples. The work has allowed for international comparison of LCA data and the paper provides an excellent example of the level of detail required by LCA analysis.

Utilising Fat Protein Corrected Milk (FPCM) as the unit for milk production, and CO₂ equivalents (CO₂e) as the Global Warming Metric, care was also taken to standardise the allocation of data, because all dairy farms are involved in growing kg of meat as well as milk. The results show a considerable range which represent differing farming systems internationally. After recalculation, New Zealand emerged with the lowest figure of 0.74kg CO2e·kg−1 FPCM with Tanzania at 5.99 kg CO2e·kg−1 FPCM the highest. The average was 2.11kg CO2e·kg−1 FPCM, a figure that compared quite well with the 2.4kg CO2e·kg−1 FPCM generated by another study. 

Detailed analysis like this only becomes truly valuable when it can be applied to monitor and implement change on actual farms. Fonterra, who commissioned some of this work, have a long term commitment to net zero by 2050 and each of their suppliers now have detailed plans, supported by expert advice, which will include veterinary input in relevant areas, to steadily reduce the intensity of emissions associated with milk production. You can find detailed information on this initiative here; a great example of LCA in action.

Life Cycle Analysis involves complex science which, in some ways, reminds one of Churchill’s famous quote about democracy, ‘democracy is the worst form of government – except for all the others.’ LCA, in all its complexities is far from perfect but it currently provides the best tool we have for measuring the environmental impact of milk production.