Assessment of Ground Flash Density in Southern Malaysia and Implications for Renewable Energy

Lightning is known to pose significant threat to electrical infrastructure, particularly in tropical regions where thunderstorm occurrence is frequent. This paper presents an investigation of lightning behavior in Southern Malaysia based on data obtained from the Lightning Location System (LLS). The main goal is to estimate the ground flash density in the study area and assess its implication for renewable energy installations. For the study, lightning data for a period of three years from 2023 to 2025 were obtained from Tenaga Nasional Berhad Research (TNBR). Cloud-to-ground (CG) lightning occurring within a 10 km radius of reference location were analyzed and their distribution as well as the peak current characteristics were determined. Subsequently, the ground flash density (GFD) of the study area was estimated. The results indicate that lightning activity in the study area is dominated by negative CG events, representing about 95% of the total recorded occurrences. The maximum peak current recorded was 215 kA for negative CG and 140 kA for positive CG flashes. Although less frequent, positive CG flashes exhibited higher geometric and arithmetic mean peak currents compared with negative CG. Based on the estimated flash counts, the ground flash density ranges between approximately 6 and 12 flashes/km2/year, which indicate moderate to high lightning exposure typical of tropical regions. In conclusion, since the area can be considered as lightning prone, renewable energy installations built in the study area require appropriate lightning protection and surge protection measures to alleviate the risk.