使用蒸汽迴路系統(包含蒸汽再熱系統)使蒸汽條件達到220.6大氣壓力以上及溫度374°C以上為超臨界蒸汽條件;使蒸汽條件達到250~300大氣壓力以上,及溫度580~600°C以上為超超臨界蒸汽條件(Supercritical and ultra-supercritical steam conditions: use of a steam circuit, including steam reheating systems, in which steam can reach pressures above 220.6 bar and temperatures above 374 °C in the case of supercritical conditions, and above 250 – 300 bar and temperatures above 580 – 600 °C in the case of ultra-supercritical conditions)