The aim of the paper is to introduce a flexible system whose objective is to help industrials and decision-makers to efficiently install a marine energy farm in a suitable area and to facilitate expertise between stakeholders. We introduced a three-step approach which allows to select marine farm sites and suitable technological solutions. The system developed is based on the combination of Geographic Information System (GIS), a multi-criteria analysis (MCA) process and an optimisation algorithm. The whole approach is illustrated by a case study applied to an installation of a set of tidal turbines in a maritime area in North West France.