Innovative macroeconomic modelling techniques for the aggregates market
Résumé
The classic belief that construction minerals are available in virtually infinite quantities has been dampened in many European countries by the permanently rising difficulties in access to the resource. A growing demand in construction aggregates has to face growing social, political and environmental constraints. As a key issue of the French-Austrian research project ANTAG (Anticipation of the access to the aggregate resource by breaking present schemes on the long term) this paper describes the building process of a System Dynamics model focusing on the competitive supply end of the French aggregates market. Strong inhomogeneities in the consumption and production pattern of France required a national subdivision and individual treatment of each of the six distinctive macro-regions. The aggregates market characterized by a low average transport distance is governed by the micro-economics of the local surroundings. A supply-and-demand equilibrium for each of the regions had to be found which has been achieved by introducing an innovative macroeconomic competition modelling approach. The production of each supply source follows from a mechanism which allocates parts of the whole market overcapacity over them. This allows piloting their relative competitiveness making the model flexible for scenarios. The monitoring of overcapacity of primary sources and the dynamics of niche markets and their interaction with the competitive market are considered. This paper also shows how missing time series data have been reconstructed making strong hypotheses, so that the authorized reserves, the extraction capacity and the actual production of a supply source of a region could be linked to each other via feedback loops.