抄録
After the Fukushima accident, worldwide renewed interests on nuclear energy called 'nuclear renaissance' suffered a sudden decrease. However, the interest on small modular reactor, characterized by important design innovations as well as safety features is continuously increasing. Following this trend, new concepts of nuclear reactors which exclude the possibilities of postulated accidents by changing reactor design and/or minimizing active components are appearing. URANUS is a lead-bismuth eutectic cooled small modular reactor which follows new reactor's design criteria, and is developed by NUTRECK, Republic of Korea. The reactor works without reactor coolant pumps and can be operated under normal and accident conditions by utilizing natural circulation of coolant. It was targeted and modularized to be used for regions where distributed power sources are needed and sized to 100 MW thermal and 40 MW electric power. Also, it is designed to be operated for 20 years without refueling so that proliferation resistance is maximized and spent nuclear fuel production is minimized. For nuclear fuel, uranium dioxide was adopted, which is well-known so far and vastly used for commercial nuclear power plants. In this study, the conceptual design of URANUS will be elaborated and future development plan and key researches on lead-bismuth cooled small modular reactor will be introduced.