Development of Analytical Tool for Energy Audit of Cogeneration plant (ATEAC)

• Main Author: AUGUSTINO YONGO, PHILIP WADEN
• Format: Thesis
• Language: English
• Published: 2010
• Subjects: TP Chemical technology
• Online Access: http://utpedia.utp.edu.my/10108/1/2010%20Master-%20Development%20OF%20Analytical%20Tool%20For%20Energy%20Audit%20Of%20Cogeneration%20Plant%20%28ATEAC%29.pdf; http://utpedia.utp.edu.my/10108/

Energy audit and management of a plant can be considered as a systematic approach to maintain the performance of a plant at high efficiency. The tedious task of energy audit of a cogeneration plant can be undertaken by aid of the analytical method which represents the working principles of the respective equipment used in a plant. The performance of the plant can be inefficient due to energy misusage and energy lost and hence, identifying the operating parameters that cause energy losses and misusage can be the technique for management of a cogeneration plant. This research discusses an analytical method for energy audit of an existing cogeneration plant in Universiti Teknologi PETRONAS (UTP). The analytical models were developed for the gas turbine engine, heat recovery steam generator, steam absorption chiller, air cooled chiller, cooling tower, and thermal energy storage. The study involves the investigation of the energy lost and imbalances within the systems which degrade the performance of the cogeneration plant. The models were defined based on the principles of thermodynamics, mass and energy balance. The analytical models were implemented using Matlab7.1 and the results were validated to that of the actual operating data. The results show that the analytical models developed are able to represent the operating principles of all the systems in the plant. It was found that the performance of the plant is not at optimum operation due to losses in the components of the plant. The energy loss in the sub-systems of the cogeneration plant is found to be 35.23%. The energy loss in the components of steam absorption chiller is 77.15% of the total energy lost inside the components. The energy loss in air cooled chiller is found to be 70.6% of the total energy loss. The energy losses in the cooling tower due to evaporated mass and convection heat transfer are 5.41% and 94.6% respectively. The energy losses in the thermal energy storage are found to be 5-22.4% of the total energy lost in thermal energy storage. The analytical models also enable strategies for optimization of the plant. Reduction in the amount of losses can be observed when selected operating parameters are changed. It was found that by decreasing the inlet temperature to the air compressor by 1-1.5 K, the net work of the turbine increases by 0.11-0.2%. In the air cooled chiller condenser, the energy loss can be decreased by 5.74-7.3% when the inlet air temperature is decreased by 1-1.5 K. In the cooling tower, the energy lost by evaporated mass can be decreased by 1.01-1.5% at the same inlet air temperature. The analytical model can be used as a tool for energy audit and management of the cogeneration plant. The energy conservation can be identified by quantifying the percentages of energy losses in each component. The performance of the cogeneration plant can be maintained at optimum by monitoring the operating parameters at optimum levels.