KEPCO partnered with EPRI to evaluate the viability of utilizing synchronous condensers to support grid stability under a case of high renewable penetration on Jeju Island. In this study EPRI provided a technology overview discussion, cost, and performance estimates representative of South Korean local labor and material rates for various ratings of synchronous condensers based on previous EPRI studies. Additionally, EPRI performed studies to evaluate the impact on Jeju Island’s inertial frequency response under various contingencies for a 2030 scenario with high renewables penetration on Jeju Island. EPRI performed 18 dynamic simulation runs for two different contingencies, three different inertia ratings, and three different synchronous condenser sizes to evaluate effectiveness of synchronous condensers and flywheels to boost inertial response. Simulation results show that a synchronous condenser could adequately support stable system operation of the Jeju power grid in 2030 with the planned renewables growth. Additional inertial support may also be required from flywheels to avoid under frequency load shedding.