Floating renewables for sustainable Malaysian Islands: A 3E assessment

• Assessed floating solar, wind turbines, and wave energy systems for Malaysian Islands. • Analyzed energy yield, LCOE, and carbon reduction using simulation tool and models. • Langkawi excels in solar, wind, and wave energy; Tioman suits wind turbines; Pangkor favors solar and wave energy. • This study provides a valuable framework for sustainable energy in Island regions. Island communities in Malaysia remain highly dependent on fossil fuel–based electricity, necessitating reliable and economically viable renewable energy alternatives. This study presents a 3E (energy, economic, and environmental) assessment of 1 MW offshore floating solar photovoltaic (OFPV), floating offshore wind (FOW), and wave energy converter (WEC) systems' feasibility at Tioman, Langkawi, and Pangkor Islands of Malaysia. Energy performance results show that OFPV systems generate 1,455.3–1,553.3 MWh/year, achieving capacity factors of 17–18% and high-performance ratios of 0.84–0.86 , with Langkawi exhibiting the most stable and favourable solar conditions. Floating offshore wind produces the annual energy output of 114.2 -853.58 MWh /year with an average capacity factor of 5 %. Among sites, Pangkor Island demonstrates limited wind potential, with capacity factors below 2 %. Wave energy systems have outputs of approximately 461-684 MWh/year , with capacity factors ranging from 5 % to 8 %, reflecting the low-to-moderate wave climate of Malaysian coastal waters, though Langkawi performs best during monsoon months. Economic analysis indicates that floating solar is the most cost-effective technology, exhibiting the lowest levelized cost of energy (LCOE) and the shortest payback period under an avoided electricity cost of RM 0.20/kWh . Floating offshore wind shows a moderate LCOE and longer payback period due to higher capital and maintenance costs, while wave energy remains economically uncompetitive, with payback periods exceeding the project lifetime. Environmentally, all systems contribute to emissions reduction by displacing diesel-based generation. Overall, the results identify Tioman as the most suitable site for wind energy deployment, Langkawi as optimal for floating solar and wave energy, and floating solar as the most viable near-term solution for sustainable island electrification in Malaysia.