Session: 09-14-01: Fundamentals and Applications of Thermodynamics

Paper Number: 165289

Comprehensive Thermodynamics Analysis of a 1260 MW Steam Power Plant: Energy and Exergy Evaluation 

Abstract

Introduction: In the modern landscape of energy production, the efficiency of thermal power plants remains a critical concern due to the global demand for sustainable and efficient energy sources. This study presents a comprehensive thermodynamic analysis of a new1260 MW steam power plant, focusing on energy and exergy efficiencies under varying dead-state temperatures and condenser pressures. While previous studies have explored these factors separately, this research examines their combined influence on component-wise exergy destruction, offering new insights into performance optimization.

Purpose of the Research: The objective of this study is to apply First and Second Law thermodynamic analysis to evaluate the performance of key components—boilers, turbines, condensers, pumps, deaerator, and feedwater heaters—in a large-scale power plant. By systematically varying dead-state temperatures and condenser pressures, this research identifies major sources of irreversibilities and proposes strategies to enhance cycle efficiency.

Contribution to Science and Engineering: Unlike previous research, which has primarily analyzed dead-state temperature effects or condenser pressure variations in isolation, this study introduces:

1.     A combined thermodynamic evaluation using the First and Second Laws of Thermodynamics to quantify efficiency losses across major plant components.

2.     A large-scale case study, assessing exergy destruction in a modern, high-capacity power plant.

3.     A detailed component-wise breakdown of irreversibility, demonstrating how varying thermodynamic conditions affect efficiency.

4.     An in-depth analysis of condenser vacuum pressure effects, revealing how sub-atmospheric pressures influence energy and exergy losses.

Methodology: A rigorous thermodynamic analysis is conducted using energy and exergy balance equations derived from the First and Second Laws of Thermodynamics. The study focuses on energy analysis to determine the First Law efficiency and assess the conversion of heat into work. Then exergy analysis to quantify irreversibility and pinpoint components with the highest exergy destruction (e.g., boiler and condenser). Lastly, parametric evaluation of varying dead-state temperatures and condenser pressures to assess their impact on system performance.

Preliminary Results: Preliminary analyses reveal that the main sources of exergy destruction are in the plant's condenser with 104 MW and boiler with 1172 MW, suggesting significant inefficiencies in heat exchange and energy conversion processes. Also, the first law efficiency is 39%, while the second law efficiency stands at 37%, confirming substantial irreversibility in the system. Variations in dead-state temperature significantly influence exergy efficiency. An increase in dead-state temperature leads to reduced exergy efficiency in the boiler, turbine, and deaerator, while exergy efficacy increases in the condenser due to the reduced temperature difference driving heat rejection. These results indicate considerable potential for enhancing the thermodynamic efficiency of the power plant by focusing on the components with the highest losses.

Conclusions & Optimization Strategies: The study concludes that there is a critical need for targeted improvements in the design and operation of boilers and condensers to reduce exergy destruction and optimize energy usage.

1. Optimizing boiler heat recovery systems to mitigate the 1172 MW exergy loss caused by combustion and heat transfer irreversibilities.

2. Enhancing condenser vacuum pressure control to minimize the 140 MW energy loss due to heat rejection inefficiencies.

3. Implementing adaptive condenser pressure regulation to balance efficiency across varying environmental conditions.

4. Refining combustion air preheating and fuel combustion strategies to minimize temperature-related exergy destruction.

By integrating First and Second Law thermodynamic analysis with real-world operational data, this study provides a comprehensive approach to optimizing large-scale steam power plants. The findings bridge the gap between theoretical thermodynamic modeling and practical efficiency enhancement strategies, making them highly applicable to modern energy systems.

Presenting Author: Saad Alsamraee university of missouri-columbia

Presenting Author Biography: Saad Alsamraee is a PhD student at the University of Missouri in the Department of Mechanical and Aerospace Engineering. His research focuses on improving the energy efficiency of power plants, aiming to develop innovative solutions for optimizing energy production and reducing waste. With a strong background in engineering, he is dedicated to advancing sustainable technologies that enhance the performance of power generation systems. His passion for research and problem-solving drives him to find practical applications for his studies, helping to improve the efficiency and environmental impact of modern power plants.

Authors:

Saad Alsamraee university of missouri-columbia
Sanjeev Khanna University of Missouri - columbia