The world is currently experiencing rapid population growth and industrialisation, contributing to an increasing global energy demand. This paper unveils a sustainable renewable energy strategy for Nakhon Ratchasima (also known as KORAT), Thailand, using the Hybrid Optimization of Multiple Energy Resources (HOMER) Software. Data was simulated to establish KORAT's microgrid system with the maximum renewable energy penetration and simulate the demand profile and climatic data. The results revealed that ‘solar power systems are closely followed by ‘hydropower systems’. The ‘wind power’ system had lower capability and cost-effectiveness due to unusual power generation, and wind speeds in the province were typically lower than the cut-in speed of the selected model of wind turbines. The ‘wind power’ and ‘storage’ systems had lower capabilities and cost-effectiveness due to unusual power generation and a considerably low amount of surplus energy (i.e., the renewable fraction was not significantly increased by adding batteries), respectively. These results would guide relevant stakeholders in decision-making processes regarding sustainable renewable energy strategies for Thailand. This study's findings can be used as a model or a prototype for modelling hybrid energy systems in other parts of Thailand.