THERMODYNAMIC (ENERGY AND EXERGY) ANALYSIS OF SOLAR ASSISTED POWER COOLING COMBINED GENERATION SYSTEMS

Abstract

The worldwide power industry structure is changing to a market economy to ensure commercial availability. This captive industry is essential for national development power & electricity infrastructure, but more than 40% of the input energy is lost during the plant operation with different thermal utilities. These precious dumped or waste heats have tremendous potential for the generation of multiple effects of energy like heating-power & cooling and also help to enhance the efficiency of thermodynamic power cycles. The novel and advanced thermodynamic systems are important because solar based on refrigeration systems have been discussed in the proposed title of research for different categories of waste heat source recovery. Therefore, this study investigates both theoretical and software-based simulation into the distinguishing feature of the advanced concept of the Rankine model called Organic Rankine Cycle (ORCs), which has three useful output heating-power and cooling production. The present research work focuses on two significant thermodynamic analyses: the integration of advanced thermodynamic cycles and the heat recovery system with employment of solar thermal systems, and the second is complete thermodynamic analysis, consisting of Energy and Exergy analysis. The traditional approach of thermodynamics analysis is based on the 1st law and 2nd law of thermodynamics. The 1st law of thermodynamics (FLT) gives the work, heat transfer, energy performance, thermal efficiency. In contrast, the 2nd law of thermodynamics (SLT) provides the system's actual performance by entropy generation (exergy) principle. The quantity and quality of energy (useful energy) are estimated through the FLT and SLT. The main objective of 2E analysis (energy-exergy) is to examine the theoretical and actual performance of proposed thermal systems to identify energy loss in integrated parts of the thermal system for efficient performance. The conventional mathematical modeling is suitable for physical system simulation, complex mathematical model development, and quantitative analysis. The statistical modeling helps to error estimation, system optimization, and comparative study of fundamental & predicted complex analysis results. Several statistical analysis methods are available with new artificial intelligence applications like linear or multi-linear regression method, artificial neural network method, least square method, and Taguchi-Annova xi | P a g e method. All optimization techniques are suitable for the least parameter identification, error count with complex problem-solving. This Research work is referred to as the multi-linear regression method for parametric identification and actual- predicted result comparisons. This research work consisted of four thermodynamics models for combined cooling, heating, and power generation effect using waste heat of different power plants. 1. Stack Flow heat recovery of Combined GT-ST plant using the LiBr-H2O vapor absorption cooling system. 2. Steam Turbine Heat recovery using solar integrated double bed activated carbonmethanol and activated carbon-R134a Vapor adsorption refrigeration system for space cooling purpose. 3. Reheating Rankine power generation heat recovery of the condenser by using a solar integrated organic Rankine cycle for combined cooling, heating, and power generation effect. 4. Combined reheating and regeneration steam power cycle, analysis and process heat recovery through a vapor generator by using the Vapour jet refrigeration system. All the above four systems are suitable for the low, medium, and high-grade temperature sources of heat recovery and produce the combined effect of energy efficiently. A parametric study has been carried out to analyze some influenced parameters such as condenser temperature, turbines (GT&ST) output, ORC performance, cooling effect of VARS, and vapor adsorption refrigeration and ejector cooling system. The influencing effect of gas turbine inlet temperature, compression ratio with different combustion of natural gases provides the best performance of the GT system for operation of ST plant under the different operating conditions of the compressor, GT, and combustion chamber. This case concluded as the maximum exergy loss found in the combustion chamber of GT system and exhaust flow system of ST system in terms of 41% and 8%, respectively. The combined and exergetic efficiency of the plant is estimated to be 41% and 38.5% respectively. In the present statistical model, 4 levels and 3 factors (Pressure ratio, operating temperature and type of fuel gases) have been considered. Furthermore, overall efficiency, gas turbine efficiency, heat loss in GT plant, Exergy destruction in thermal xii | P a g e utilities like Compressor, combustion chamber and gas turbine are investigated. The statistical modeling concluded that the comparative results of actual and predicted results at different compression ratio of combustible gases which affects the overall performance of combined GT-ST plant. This study helps to justify possible efficiency improvement by identifying the irreversibility of plant utilities. The combined reheating-regeneration power generation analysis concluded that the energy- exergy analysis for the Boiler, turbines, Feed heaters, condenser and pump majorly. The result of the thermodynamic analysis is computed as 42% of plant thermal efficiency, 70 % of steam generation unit efficiency. Maximum heat absorbed by economizer of plant as 39% is achieved, and quality of steam was found around 89-90% with 40TPH of coal consumption. Boilers, HPT, IPT, Super heaters have found best performance in analysis and Reheating-Regenerative Rankine method improves 6-8% in thermal efficiency. It has been observed that energy efficiency (theoretical) is always more than energy efficiency (actual), which means it helps to understand the performance of thermal power plants and justify possible efficiency improvement with efficient power generation opportunities like waste heat recovery technology employment. The performance of cooling systems of proposed research work is carried out the source temperatures available for both beds of Vapor adsorption refrigeration systems (VAdRS) from condenser exhaust, ETC solar system. The adsorbent and adsorbate pair for double bed VAdRS has been recommended by activated carbon as adsorbent and methanol and R134a as the adsorbate. The significant findings of present work are the maximum irreversibility found in Boiler as 47% in thermal power plants and solar generators as 12% of adsorption machines, whereas overall cooling effect from adsorption systems increases by 15% in double bed combination. EES software is used for all analyses. The VAM machine for stack flow heat recovery is performed by 0.708 of COP, a suitable cooling for space and water chilling purposes.