Assessment of future renewable energy scenarios in South Korea based on costs, emissions and weather-driven hourly simulation

The energy policy released by the South Korean government in 2017 aims to gradually increase renewable energy to 20% while reducing the number of nuclear and coal power plants by 2030. The constant controversy over the feasibility of this policy – which arose soon after its release – led to a number of studies focussed on the environmental, economic, political and social issues related to the current policy. However, none of these investigated the hourly dynamics of renewable energy supply, which is crucial to provide an accurate assessment of an energy policy and a technical evaluation of its feasibility. In this study, we analyse four potential renewable energy scenarios for 2030: Business as Usual, Strengthened Solar (i.e. the new energy policy), Strengthened Wind, and our Suggested Scenario. Using a bottom-up energy system modelling approach, we simulated solar and wind power generation at the hourly level, integrating weather data provided by the NASA MERRA-2 reanalysis database. In addition to the feasibility of each scenario, evaluated using annual generation and capacity factors, we also examined the environmental and cost impacts through a number of different measures. Our results show that both the Strengthened Solar and Strengthened Wind scenarios fail to meet the CO2 emission target proposed by the government. From the economic point of view, our cost analysis demonstrates that renewable energy is sustainable for either Strengthened scenarios and cost-effective in both the short term and long term, despite the high capital cost. Instead, our suggested scenario proves to be the optimal solution by meeting the CO2 emission target and minimising costs. Therefore, our hourly simulation provides crucial evidence to assess the new energy policy and to evaluate alternative solutions for the future energy system of South Korea.