Constant Steam Inlet Conditions and their Impact on the Thermal Efficiency of a Cogeneration Power Plant

Abstract

Cogeneration, a process facilitating the simultaneous production of electricity and useful heat from a singular energy source, has been investigated in this study. The primary objective of this research was to assess the performance dynamics of a cogeneration power plant under constant steam inlet conditions. Results revealed that the thermal efficiency (Ƞth) oscillated between 23.76% and 24.44%. The maximum thermal efficiency recorded was 24.44%, corresponding to an Energy Utilization Factor (EUF) of 0.85, under an inlet temperature of 502℃. Conversely, the lowest thermal efficiency measured was 23.76%, with an EUF of 0.72, observed at an inlet temperature of 503℃. These findings underscore the system's proficient energy utilization, notwithstanding minor fluctuations in steam parameters, such as inlet and various stages of operating conditions. A positive relationship was established between the heat-to-power ratio and the overall efficiency, which varied between 70.59% and 76.49% across different pressure values. The peak efficiency was noted at 84.7 kgf/cm 2 . Moreover, the EUF exhibited a range from 0.72 to 0.85, indicative of the system's energy use efficiency. A higher EUF value implies a more effective use of energy. At an EUF of 0.85, the cogeneration power plant demonstrated an impressive overall efficiency of 75.13%, signifying highly efficient energy conversion and utilization. However, at an EUF of 0.72, the overall efficiency declined to 70.59%, pointing to reduced efficiency in energy utilization. These results emphasize the critical role of maintaining a constant mass flow rate of steam and optimizing inlet parameters to enhance the efficiency of cogeneration power plants. Consequently, this study provides valuable insights into the operational optimization of cogeneration power plants.