Energy and exergy analysis in a natural gas combined cycle power plant

The continues increasing population and industrialization rate and the increasing energy demand makes it a necessity to use energy more efficiently. When viewed from the perspective of Turkey, imported resources come to the forefront in meeting this increasing demand. Approximately 32% of our electricity need is generated through natural gas-fired combined cycle power plants while the vast majority of our natural gas is imported. Energy efficiency is of the utmost importance for Turkey in order to enter a sustainable development era. In this respect, efficient use and savings of energy in Turkey's electricity production plants has a great importance for the security and future of Turkey. Natural gas fueled combined steam and gas cycle power plants having a share of 25 thousand MW installed capacity in Turkey that if the plants are able to provide even a small increase in energy efficiency, will return millions of Turkish Liras back to the economy. Thus, resources of earth could be used in a efficient and effective way. In this study, a 770 MW natural gas fueled combined cycle power plant was analyzed and assessed in terms of energetic and exergetic performance. For this purpose, real data-set was collected from the plant and designated processes created in a simulation environment using Aspen HYSYS packed programme and results were compared with calculations and real process data. Furthermore, by establishing mass, energy and exergy balances and equations in every vital equipment of the plant; separate energy and exergy analyzes were performed and second law efficiencies were calculated. In accordance with the results, the energy amount that can be recovered from the power plant processes is calculated and the potential exergetic improvements are determined. Finally, on the basis of the findings obtained, the improvement of the cooling effect of the compressor inlet air and its effect on the system performance were investigated.