On the Definition of a Comprehensive Technology-Informed Accessibility Metric for Offshore Renewable Energy Site Selection

Despite the important role of offshore renewable energies (OREs) in the energy transition, the economical viability is still unclear. Therefore, an appropriate site selection is crucial. Besides the energy potential, the impact of operation and maintenance (O&M) aspects on the location can be critical. Accessibility is one of the most relevant aspects for O&M, assessing the feasibility to access the ORE farm. However, traditional accessibility assessment metrics do not allow a comprehensive evaluation. Therefore, the present paper suggests a novel, technology-informed metric, incorporating the overall set of most critical aspects, i.e., metocean conditions, visibility due to sunlight and sea fog, system failures, and O&M logistics. Among the different aspects, limited visibility is shown to be highly relevant with a reduction of up to 60% in accessibility. The study assesses accessibility in five different locations across Europe. On the one hand, accessibility is shown to be less sensitive to long-term resource variations with a reduction of 5% in the last six decades. On the other hand, accessibility is overall shown to be inversely proportional to the energy potential, meaning that as the energy potential increases, accessibility is reduced, increasing downtime, reducing the energy generation and increasing the cost of energy. As a consequence, site selection should combine the energy potential and accessibility assessments, which is enabled by the technology-informed metric presented here.