2021. Techno Economy Comparison of Conventional Generating Unit and Lithium Battery Energy Storage as a Primary Frequency Regulation of Variable Renewable Energy Penetrated Grid System, Case Study: Southern Sulawesi of Indonesia. European Journal of Engineering Science and Technology. 4, 3 (Dec. 2021), 25–38. DOI:https://doi.org/10.33422/ejest.v4i3.739.