Energy Mix based on the National Master Plan for Energy and Changes of Life Cycle GHG Emission Factors

The energy mix serves as the basis for calculating the greenhouse gas (GHG) emission factor of electricity, and therefore has a significant impact not only on the evaluation of GHG-related policies but also on the carbon footprint of industries that use electricity in life cycle assessments (LCA). As such, there is a need to annually publish GHG emission factors that reflect changes in the energy mix. The purpose of this study is to present IPCC- and LCA-based GHG emission factors and GHG emissions for the energy sector based on changes in the energy mix, and to assess whether the nationally determined contribution (NDC) can be achieved under these conditions. To achieve this, the study applies Intergovernmental Panel on Climate Change (IPCC) and LCA-based GHG emission factors for each power source to the energy mix outlined in the 10th Basic Plan for Electricity Supply and Demand, calculating annual (2018~2036) national electricity GHG emission factors and emissions, and analyzing the feasibility of meeting the NDC target. The analysis revealed that GHG emission factors fluctuate significantly with changes in the energy mix, underscoring the need for annual calculations. Under the planned energy mix, GHG emissions from the energy transition sector are projected to reach 159.9 million tons CO2eq, which exceeds the NDC target of 149.9 million tons CO2eq. However, reducing coal-fired power generation by 10% and replacing it with offshore wind and solar power could make achieving the target feasible. Additionally, the LCA-based GHG emission factors indicate that expanding offshore wind and solar power instead of relying on hydrogen and ammonia in the energy mix could achieve a 2.5% reduction. Therefore, adopting methodologies such as those used in this study to calculate annual GHG emission factors would allow efforts to transition the energy mix to be immediately reflected. Furthermore, when planning the energy mix, an LCA-based approach rather than an IPCC-based approach would provide a more effective means of responding to practical environmental regulations