Energetic and Exergetic Analysis of Combined Cycle Power Plant: Part-1 Operation and Performance

Abstract

Energetic and exergetic analyses are conducted using operating data for Sabiya, a combined cycle power plant (CCPP) with an advanced triple pressure reheat heat recovery steam generator (HRSG). Furthermore, a sensitivity analysis is carried out on the HRSG using a recent approach to differentiate between the sources of irreversibility. The proposed system was modelled using the IPSEpro software and further validated by the manufacturer's data. The performance of the Sabiya CCPP was examined for different climatic conditions, pressure ratios, pinch point temperatures, high-pressure steam, and condenser pressure values. The results confirmed that 60.9% of the total exergy destruction occurs in the combustion chamber, which constitutes the main source of irreversibilities within a system. The exergy destruction was significantly affected by both the pressure ratio and the high-pressure steam, where the relation between them was seen to be inversely proportional. The high-pressure stage contributes about 50% of the exergy destruction within the HRSG compared to other stages and the reheat system, due to the high temperature difference between the streams and the large number of components, which leads to high energy loss to the surroundings. Numerous possibilities for improving the CCPP's performance are introduced, based on the obtained results.

Probabilistic Exergoeconomic Analysis of Transcorp Power Plant, Ughelli

“…In the environmental state, the system is mechanically and thermally at equilibrium state, but not chemically [6].…”

Probabilistic Exergoeconomic Analysis of Transcorp Power Plant Ughelli

“…In the environmental state, the system is mechanically and thermally at equilibrium state, but not chemically [6]. The chemical exergy for fuel stream is given by:…”

“…According to Almutairi et al [6], that due to their high energy conversion efficiency, which is necessary in order to delay the depletion of non-renewable resources, by reducing fossil fuel consumption, through utilizing and recovering part of the waste energy from a gas turbine engine and from an environmental perspective, it reduces greenhouse gas emissions, and, thus, the changes in the climate decrease significantly. The environment is significantly affected by inefficiencies within the power system.…”

“…The exergy method is a performance analysis of a thermal system based on the second law of thermodynamics which extends beyond the limits of energy-based analysis since exergy is generally not conserved as energy but is destroyed in the system. The exergy method assists in identifying the source and magnitude of performance loss in a thermal system by measuring the irreversibilities that occur in different components and locations of the system [4][5][6]. Energy analysis is only able to quantify efficiency of plants without pin pointing components energy losses and cannot able to assess the qualities of the energy.…”

Exergy Analysis of Combined Effect of Evaporative Cooling and Steam Injection on Gas Turbines Performance Enhancement in Hot and Humid Climates

“…The HRSG consists of an economizer, an evaporator with drum and a superheater (Almutairi et.al, [10]). The output of the GT is passed through the a heat exchanger to recover the waste heat and to generate superheated steam and high pressure that is injected into the combustion chamber to be mixed with the fuel or is injected around the fuel nozzle tips for controlling NO x production.…”