Power Plant Performance Study & Heat Rate Improvement through Energy Audit

Abstract

Fossil fuel stack is decreasing day by day and global energy concerns are increasing. Lot of research is going on in development of alternate fuel but till date effective solution is not achieved. In present scenario to last available resources of fuel for longer duration its efficient use is required. One of the approaches in this direction is to measure performance of various equipments using energy and to optimize its performance for conservation of energy. This can be achieved by carrying out energy audit of various equipments. Energy Audit should cover evaluation of the present performance level of all major equipments, identify the controllable losses and suggest remedial measures for improvements with cost benefit analysis and payback period. Performance tests can be carried out using installing high accuracy offline test instruments or using the online plant instrumentation. The primary objective of energy conservation practise is to extract maximum energy from fuel used and to utilize it most effective way in thermal power plant. In power plant energy conservation analysis should be carried out for air compressor, air pre-heater, cooling tower, boiler, turbine, induced draft fan, forced draft fan, condenser and other equipments. In present work energy audit of air compressor and air pre-heater and cooling tower was carried out. For 32 air compressors system analysis was carried out by determining volumetric efficiency, actual isothermal efficiency and specific energy consumption. Based on specific energy consumption these compressors are categorized in poor, satisfactory and good compressors. By controlling leakage losses in three compressors actual isotherm efficiency was improved by 1.23% and specific energy consumption is decreased by 0.03kWh/m3hr. Effectiveness of air pre-heather is used to measure its performance. In energy audit of air pre-heater by calculating O2 the leakage can be found and by taking appropriate remedial actions its effectiveness can be improved. In cooling tower, seven cooling tower energy audit carried out and base on that find the effectiveness of cooling tower and find out which cooling tower had more water consumption. Also determine exergy analysis find the second law efficiency of Auxiliary like air compressor, air pre-heater, and cooling tower. Compared the heat rate of power plant with design heat rate. Keyword: Energy Audit, Air pre-heater, Air compressor, Cooling tower, Effect of leakage, Heat rate, Exergy Analysis.