Examination of co-utilization of nuclear and renewable energy in the Republic of Korea

Abstract

As nuclear power is responsible for more than 30 percent of total electricity generation in Korea, co-utilization of nuclear and renewable energy is garnering attention as a strategic carbon-free option in conjunction with the Korean government’s pro-renewable stance. As such this co-utilization strategy is well poised to balance, enhance, and complement those two technologies, providing reliable supplies of electricity. From this perspective, a Nuclear-Renewable Hybrid Energy System (NHES) is a potential game-changer for Korea’s evolving electricity grids that are aimed at balancing the intermittency from renewables, while improving overall economics in the power sector. This thesis investigates scientifically sound and commercially rational ways to use nuclear power effectively under a hypothetical scenario of large-scale deployment of wind and photovoltaic (PV) generation. To explore the techno-economic performance of NHESs, two different co-utilization configurations were analyzed, with particular emphasis on CO2 reduction and operating cost savings: 1) Nuclear-Wind Hybrid Energy System for District Heating (DH), and 2) Nuclear-PV-Demand Response (DR) Hybrid Energy System for an alternative ESS (Energy Storage System). In addition, a decision support framework was developed for future implementation of the NHESs. This framework will help identify how the advantages and disadvantages of each nuclear-renewable combination could impact the success of a Nuclear- Renewable integration goal. The first scenario shows that a Nuclear-Wind Hybrid Energy System for DH could increase total system efficiency from 30 percent to > 41 percent while mitigating a windfarm’s intermittency. This cogeneration system is parameterized to represent the SMART (System-integrated Modular Advanced ReacTor) to advance strategic business models envisioned for small modular reactors (SMRs). Whereas the second scenario, using the Nuclear-PV-DR Hybrid Energy System, shows that harnessing the DR resources as an alternative form of energy storage would minimize the impact of fluctuations in solar energy, providing greater grid flexibility. These two scenarios can be achieved more economically than the current reference cases. Research findings demonstrate the viability of hybrid systems and how their applications can expand nuclear energy use while facilitating more flexible grid operation. This synergy will foster the growth of renewable capacity. Lastly, the results identify and quantify experts’ perceptions of the aforementioned co-utilization options within the Korean context.