Combined AHP-GIS methodology for floating offshore wind site selection in South Africa

A sustainable approach to site selection can enhance the techno-economic feasibility of floating wind projects. This is because site selection is a multicriteria problem including technical, environmental, social, and economic factors. The issue is more pronounced in emerging and future markets where market and policy developments do not account for the complex life cycle aspects of technology development. Moreover, previous offshore wind site selection studies have utilised multi-criteria decision-making (MCDM) approaches that are not directly integrated with GIS software for mapping of the most attractive sites. The implication for prospective markets is that it fails to address the ambiguity regarding the feasibility of floating offshore wind technology, especially with knowledge of its high development costs. This study tackles the problem by deploying a multidisciplinary methodology for selecting the best sites for floating offshore wind turbines (FOWT) in South Africa. It included analytical hierarchy process (AHP) pairwise judgements from experts to assess the evaluation criteria, a Geographic Information System (GIS) analysis to implement results in South Africa's Exclusive Economic Zone (EEZ), and windPRO simulations to assess the actual development potential of the technology in the selected sites. The AHP final weights constitutes a comprehensive set of evaluation criteria for future studies in floating wind site selection. Results also show that 25 sites in the Northern Cape (NC), Western Cape (WC), Eastern Cape (EC), and Kwazulu Natal (KN) regions of the country can host over 71 GW of floating wind capacity. To achieve this potential, industry actors and policymakers must prioritise selected sites with considerations of the characteristics that may influence the techno-economic feasibility of future floating wind projects in South Africa. • AHP weights display the ranking of priorities in floating wind development in current, emerging, and future markets. • 25 sites in Northern Cape, Western Cape, Eastern Cape, and Kwazulu Natal can host over 71 GW of floating wind capacity. • The characteristics of selected sites can inform the techno-economic feasibility of future floating wind projects.