This paper presents a detailed feasibility study and techno-economic evaluation of a hybrid solar-wind system with battery energy storage for a standalone remote island (about 100 residents) in Hong Kong. The study was conducted based on a completed year recorded solar radiation and wind speed data in 2009. HOMER software was employed to do simulations and perform techno-economic evaluation. Thousands of cases have been carried out to achieve an optimal autonomous system configuration, in terms of system net present cost (NPC) and cost of energy (COE). A detailed analysis, description and expected performance of the proposed system were presented. The simple payback time of the system was also evaluated. Moreover, the effects of the PV, wind turbine, battery bank capacity on the system’s reliability and economic performance were examined. Finally, a sensitivity analysis on load and renewable energy resource was performed to evaluate the robustness of economic analysis and identify which variable has the greatest impact on the results. The results demonstrate the feasibility of implementing the hybrid solar-wind-battery system on this island. The methodology employed in this study could be viewed a benchmark for planning and sizing hybrid renewable systems suitable for similar remote islands around the coast of China and Hong Kong.