Energy audit of gas based combined cycle power plant and analysis for energy efficiency improvements

This paper addresses the implementation method of energy audit of Combined Cycle Plants and Analysis for Energy Efficiency Improvements. Combined Cycle Plants are now considered among the most energy efficient systems for power generation from fossil fuels with gross efficiencies in some cases going as high as 60%. Further reduction in energy consumption per unit of production along with reduced operating costs can be identified by carrying out energy audit of the facilities which help in identifying the scope of improvements in the system. In this paper, an Energy Audit Analysis of a Combined Cycle Power Plant (CCPP) at Centre for Power Efficiency in Distribution (CENPEID), New Delhi has been carried out. The energy analysis has been carried out for different main components of the power plant. Based on the observations and data collected from the site for the operation of the plant under different conditions and further calculations, it was found that the performance parameters of the plant like heat rate and specific fuel consumption are highly deviant from the ISO or the design conditions for which the plant was conceived. The major reasons for the deviation of the actual performance of the plant from the design performance are seen to be the constant part load operation of the plant due to unavailability of fuel for the plant, aging of the plant and the poor maintenance of the plant. Recommendations based on the energy audit and calculations made are proposed to review the operating philosophy of the plant and provide cost effective ancillary equipment to the plant which would help in reducing the deviation of the performance parameters by operation at conditions closer to the design conditions and providing more energy efficient systems of operation.