EXERGY ANALYSIS OF THERMAL POWER PLANTS

Abstract

Exergy based efficiencies provide measure of approach to ideality means it also consider quality of energy. Variation of exergy efficiencies of thermal power plant at different reference temperature is carried out and component of power plant with largest exergy loss is calculated. Boiler has maximum exergy losses. About more than 70 % of total exergy destruction takes place in boiler, as it contains maximum irreversibilities. Pumps, Heaters and De-aerator have insignificant percent exergy loss so it became clear that boiler needs significant improvement rather than other component of the thermal power plant. Variation in exergy efficiencies of boiler, turbine and condenser with different reference temperatures is calculated. This report also include exegy analysis of boiler component ,by analyzing whole thermal plant it was very clear that boiler was having maximum exergy losses, so in problem2 the boiler part of Indian thermal power plant was analyzed with the equation presented in model development section, with environment temperature 298.15 K and 101.3kPa, respectively.. Exergy destruction of furnace, super-heater economizer were calculated, it became clear that within boiler maximum exergy destruction takes place in furnace, which results in 50.27% of total boiler exergetic efficiency . To minimize exergy destruction in boiler, heating of feed is done by 47OC which increases exergetic efficiency by 2%.