Kun Jai Lee

Environmental assessment of nuclear power generation in Korea

Nuclear energy is the major source of the electricity generation due to the lack of domestic energy in Korea. In recent years, environmental preservation concern has been increased for more efficient management of nuclear energy. Therefore it is necessary to apply Life Cycle Assessment (LCA) methodology including environmental management system, waste reduction schemes and environmental analysis methods. In this study, LCA methodology is introduced to the nuclear power generation system and environmental burden caused by this system is assessed. This study suggests new methodology for environmental assessment and establishes the extensive infra-database related with nuclear power generation system. Also, it is possible to improve the scientific basis of LCA with the emphasis on the nuclear power generation system. Therefore, this study consists of general framework of LCA such as goal and scope, inventory analysis, impact assessment, and valuation of the nuclear power generation system. The major objectives are to identify the environmental impact and the environmentally most dominant stage in life cycle of nuclear power generation system and to suggest the new methodology to solve the problem when LCA is applied to facility releasing the radioactive wastes. Thus this study is useful to improve the environmental impact assessment of nuclear power generation system and to promote the methodology of LCA.

Low temperature synthesis of PbTiO3 thin films by MOCVD without carrier gas

Abstract A new MOCVD (metal–organic chemical vapor deposition) technique employing the precursor delivery without carrier gas was developed in the deposition of PbTiO 3 thin films, which enables low temperature (450°C) synthesis and high grow rates (∼6.0 μ m/h). Substrates used were bare Si, TiO 2 buffered Si, and platinized Si. Tetraethyl lead, titanium tetra-isopropoxide, and oxygen were used as precursors. Perovskite PbTiO 3 thin films were successfully grown on all kinds of substrates investigated at the substrate temperature of 450°C. However, the C–V characteristics of perovskite thin films prepared at low temperature did not always show normal ferroelectric behavior. Without carrier gas, impinging of non-adsorbing species with substrates would be suppressed as much as possible. The difference in growth behaviors with or without carrier gas was compared with each other.

Nuclear energy system for the global environmental regulation in Korea— Energy-economy interaction model analysis

Global environmental regulation such as limits on CO2 emissions will change the energy cost as well as energy mix, and it will eventually affect the potential economic growth and future energy demand. The rise of energy price from the environmental regulation will encourage the efficiency increase of energy use, fuel switching and the substitution between the energy and the other factors of production like labour and capital. Such situations can be successfully simulated through an energy-economy model which permits two-way interaction between energy and economy. n nAn analysis on the role of nuclear energy system for meeting the global environmental constraint like CO2 emission regulation, has been performed through an energy-economy interaction model - EFOM-MACRO-KOREA. n nIn case carbon taxation which is a widely discussed policy measure for CO2 abatement should be introduced, the role of nuclear energy in the domestic sustainable energy system as well as the economic impacts has been assessed. For the analysis, various scenarios in tax rate have been considered. Levying carbon tax will decrease future economic growth, and the decrease will be bigger in case that there are some restrictions on nuclear installation. It is shown that nuclear energy system will play an important role in Korean sustainable development up to 2040 in most cases.