Development of an Open Source GIS Based Decision Support System for locating Wind Farms in Wallonia (Sourthern Belgium)

The Walloon Region - Southern Belgium – aims at significantly increasing its wind-power electricity production capacity by the end of 2020. Such a development requires a comprehensive body of reliable procedures pertaining to land use and landscape issues and subsequent controversy arising from wind farms located in densely populated areas. These procedures should enable experts and decision-makers to perform robust impact assessment analyses.
To this end, an analytical framework based on GIS functionalities has been developed to evaluate and contrast various constraints against suitability criteria regarding building wind farms. This system can perform exhaustive spatial analyses over the whole region, i.e. 17,000 km², using a 10-m resolution in a raster mode.
The approach is two-fold. Firstly, the framework allows an aggregation of 40 criteria related to both environmental and landscape constraints. The aggregation process is derived from Boolean algebra. It results into a 3-level constraint scale, i.e. exclusion, highly sensitive and sensitive. Secondly, the framework involves a weighted linear combination aggregation method where criteria are standardized on a [0,1] scale prior to aggregation. Different weights are required to translate criteria into a preference scale. In this process, the constraint map can be used as a mask for further suitability analysis.
The geo-database and analysis functionalities were developed in an open source GIS GRASS environment. These functionalities are used to either import or export data from other GIS platforms, to update constraint and suitability maps, to perform an analysis of sensitivity with regard to criteria-defining parameters, and to perform exhaustive appraisals of wind farm projects. Grass GIS-tools seem to offer a good alternative to commercial GIS software for the development of such a Decision Support System as they ensure an easier access to stakeholders involved in the development of wind energy in Wallonia.