S.M. Beselly, M.A. Sajali, K. Murakami, M.R. Sya'bana
Indonesia's southern Java coast has long been recognized for its high wave-energy potential, yet localized assessments - especially along the Malang coastline - remain sparse. This lack of site-specific data poses a barrier to effective Wave Energy Converter (WEC) deployment, which depends on accurate resource mapping and siting strategies. This study addresses the data gap by conducting a high-resolution wave energy resource assessment and identifying optimal WEC deployment sites along the south coast of Malang Regency, East Java. We utilized the Delft3D-WAVE module incorporating the SWAN spectral model, forced with ERA5 for the full year of 2023. The model domain was downscaled to 200-500 m resolution to capture nearshore variability, and outputs included significant wave height, peak wave period, direction, and wave power density (WPD). A multi-criteria approach was applied to evaluate five candidate sites based on resource level, water depth, and distance from shore. The results reveal a strong seasonal signal, with southeast monsoon waves producing peak offshore WPD values exceeding 40 kW/m, while calmer northwest monsoon conditions generate WPD values of 5-10 kW/m. Spatially, nearshore WPD ranged from 12-18 kW/m, with Site 1 identified as the most technically and economically balanced option. Site 3 offers comparable resources but is very shallow, favoring shoreline or nearshore device types. This study provides a replicable framework for wave energy site selection in data-sparse coastal regions of Indonesia. It highlights the importance of integrating seasonal dynamics, local bathymetry, and engineering criteria to support the sustainable development of marine renewable energy. © 2026 Published under licence by IOP Publishing Ltd.
Water Resources Engineering Department, Faculty of Engineering, Universitas Brawijaya, Malang, Indonesia; Department of Coastal and Urban Risk and Resilience, IHE Delft Institute for Water Education, Delft, Netherlands; Department of Civil and Environmental Engineering, University of Miyazaki, Miyazaki, Japan
