WIND RENEWABLE ENERGY LOGISTIC SHIPS (WRELS) FOR DECARBONIZING ARCHIPELAGIC MARITIME TRANSPORTATION: AERODYNAMIC PERFORMANCE, WEATHER ROUTING, AND AN EVIDENCE-BASED ASSESSMENT FOR INDONESIA

Abstract

This paper develops an evidence-based engineering appraisal of wind-assisted ship propulsion (WASP) for Indonesian inter-island logistics. The proposed Wind Renewable Energy Logistic Ship (WRELS) integrates Flettner rotors, optional rigid or suction sails, weather-informed routing, propulsion matching, and operational energy monitoring. Official Statistics Indonesia (BPS) sea transportation publication metadata for 2021–2024, IMO guidance, and traceable peer-reviewed research are used to establish the context and methods. Because vessel-specific sea trials, port datasets, and calibrated wind resource files were not supplied, the numerical values in the submitted manuscript are assessed only as illustrative assumptions, not measured Indonesian outcomes. The change from 14.2 to 9.8 L/NM corresponds arithmetically to a 31.0% decrease under equal operating conditions; this is not a validated retrofit saving. A proposed economic case of USD 1.45 million investment and USD 385,000 annual gross savings implies a simple payback of 3.77 years before maintenance, financing and downtime. EEOI and regulatory CII ratings cannot be established from fuel-use assumptions alone. A reproducible validation protocol is provided for future route-level deployment.