抄録
Plant efficiency enhancement is indispensable in order to reduce CO2 emission. Improvement of steam condition is the most effective for higher plant efficiency. In this paper, 700-degC class USC plant technology, especially the system design and materials for high temperature turbine systems, is discussed. It is believed that a 700-deg C class steam turbine system will be realized with Ni-based super alloys. It will be introduced two kinds of system. One system is 700-deg C class reheat temperature and 600-deg C class main steam temperature system which have a good level of thermal efficiency and require only light remodeling without the heavy use of Ni-based alloys. And one system is 700-deg C class main and reheat steam temperature system which have a high level of thermal efficiency.
