Regional rather than Individual-Farm Targets for Climate-Change Mitigation

Policies for reducing agricultural greenhouse gas emissions are both more effective and more efficient when set at regional rather than individual-farm level. This approach can help us achieve climate targets in a more cost-efficient manner.

Switzerland and other countries have set ambitious targets for reducing agricultural greenhouse gas (GHG) emissions. To meet these targets, farmers must implement effective and efficient mitigation measures. Often, however, these policies are neither particularly effective (i.e. they fail to achieve their targets) or efficient (taxpayers and farmers find them too costly). Using a bioeconomic modelling approach and data from 65 dairy farms in the Canton of Zurich, researchers from ETH Zurich and Agroscope analysed ways in which agricultural emission reduction targets could be formulated more effectively and efficiently.

Modelling the efficacy of various policies

Experts have analysed two different GHG reduction approaches and how they differ in terms of cost efficiency. The first approach set uniform emission reduction targets for all farms (farm-level targets), so that every farmer had to reduce emissions by the same amount. The second approach set the target at regional level, so that the farms were jointly responsible for achieving the target. This allowed the heterogeneity of the farms to be taken into account, with each farmer making a different contribution to the overall reduction target depending on their individual opportunity costs. Researchers used a simulation and optimisation approach based on the bioeconomic farm model FarmDyn, which was parametrised for a sample of 65 dairy farms to calculate the differences in income reduction for different emission reduction target percentages. The following mitigation measures were considered: (1) replacing concentrates with legumes grown on the farm; (2) increasing the number of lactations per dairy cow; (3) slurry spreading using trailing hoses; and (4)  introducing feed additives to reduce enteric fermentation in cattle. These measures were chosen since they effectively lowered GHG emissions for each kilogram of milk produced on each farm.

Increasing cost-effectiveness with regional-level targets

The results of the study show that emission reduction targets at regional level are more cost-efficient than those at individual-farm level. For example, a 10% reduction in GHG emissions per farm would mean an average income reduction of CHF 4654 per farm. If, however, all the farms in a region are jointly responsible for achieving the 10% reduction, the average costs per farm come to just CHF 545, making the regional reduction target 88% more cost-efficient. This is primarily because the marginal abatement costs for some farms are much lower than for others, allowing certain farms to achieve a greater reduction than the stipulated target at lower cost. This allows farms with higher costs to reduce their emissions by a lower amount whilst still contributing to the overall reduction target.