Evolution of Power Cycle Efficiency and Heat Rate
Evolution of Boiler technology is directly related to metallurgical evolution of boiler tube materials. Power generation through fossil fuel firing system is operated on modified Rankine cycle. The cycle efficiency increases with increase in operating pressure and temperature. Main limiting factor for increasing temperature is metallurgy of the boiler tube. The sub critical, low super critical, super critical and ultra super critical technology are evolved with increasing pressure and temperature of the cycle. The main parameters of the above cycle are as follows: Unit size Main Steam Pressure Main Steam Temperature Reheat Steam Temperature Sub-critical 500 MW 166 bar 538°C 538°C Low supercritical 660 MW 247 bar 538°C 565°C Ultra supercritical 800 MW 270 bar 565°C ...