SYNERGY: a bio economic model assessing the economic and environmental impacts of increased regional protein self-sufficiency

The European Union (EU) relies on imports to meet the protein requirements of livestock. The Common Agricultural Policy aims at improving EU protein self-sufficiency by developing the production of protein-rich crops such as legumes. The purpose of this paper is to assess the impacts of increased protein self-sufficiency through legume development at the regional level. To do so, the SYNERGY bio-economic model is set up. This model accounts for (i) different scales, (ii) different types of farm, (iii) different pedological and climatic conditions and (iv) possible exchanges of organic fertilizers and crops between farms. It analyzes both economic and environmental impacts, in terms of revenues and use of nitrogen. The main assumption is that the complementarity between specialized crop farms and livestock farms can increase protein self-sufficiency while having positive economic and environmental impacts at the regional level. The results show that protein self-sufficiency can be slightly enhanced thanks to exchanges between farms, as long as locally purchased crops are at least 10% cheaper than world purchased ones. This price differential can represent the saving in terms of transport and transaction costs. When local exchanges are possible and a GMO-free certification is set up, legume-based rations are dominant in livestock farms, and the protein self-sufficiency is even more enhanced. In both situations, the economic consequences are positive as incomes increase at the regional level. However, the impacts in term of nitrogen management are more reserved.