Malaysia targets to achieve an energy mix that is inclusive of at least 20% of renewable energies by the year 2025. Large-scale solar photovoltaic system (LSS-PV) emerged as the most preferable choice in Malaysia. Energy Commission (EC) Malaysia has launched competitive bidding on LSS since 2016 with a capacity of 500 MW in Peninsular Malaysia and targets to add the solar capacity in Peninsula Malaysia to 500 MW by 2021. Solar energy is a very intermittent source which causes voltage variation. This project aims to overcome the shortcomings of the intermittency of solar energy by identifying an optimum PV panel sizing and configuration that reduces the intermittency of the supply. The project was carried out in three distinctive stages; first suitable sites were selected based on the EC proposed locations and further scrutinized to locations near the Main Transmission intake. The second stage was to size of PV panels and the inverters. The optimization was carried out at the PV module level. Suitable inverters for the said configuration was identified with a tool that evaluates the technical aspects of renewable energy power systems. The final stage was the economic analysis and environmental assessment. The optimization method has shown improvement in the system production from a range of 1.7–3.9% in the 30 MW plants. Countries with similar climates as Malaysia like Indonesia, Philippines and Thailand can adopt this optimizing method to size PV farms.