Investigating The Use Of Water For Electricity Generation At Turkish Power Plants

Abstract

The water-energy intertwined relationship has recently gained more importance due to the high water consumption in the energy sector and to the limited availability of the water resources. The energy production is a water intensive process in which water is consumed for fuel extraction, fuel processing, and electricity generation which results in the largest share of water consumption among other processes. Thus, investigating the amount of water consumed during electricity generation at power plants has become an important issue in energy-water nexus. The energy and electricity demand of Turkey has been increasing rapidly in the last two decades. More thermal power plants are expected to be built in the near future to supply the rapidly increasing electricity demand in Turkey. In this study, the water consumption for electricity generation at the Turkish power plants is investigated. The main objectives of this study are to identify the amount of water consumed to generate 1 GWh of electricity for each fuel type currently used in Turkey and to investigate ways to reduce the water consumption at power plants expected to be built in the near future to supply the increasing demand. In the first stage of the study, installed capacity, fuel and technology types, electricity generation, and if available cooling system type data of over 1500 power plants, cooling-system water consumption factors, renewable energy potential, and electricity demand forecasts are gathered from various sources. Then, the data are analyzed to determine the water consumption of the current power plants, and the total and per generation water consumption at Turkish electricity sector in 2016. The analysis resulted that based on the installed capacity 44% of the power plants use wet cooling towers as their cooling system type, which consume more water than once through or dry cooling systems. Also coal/lignite fueled power plants consume 71% of the total water consumed at electricity generation in 2016 which is determined as 188 million m3. The analyses also show that the 693 m3 of water is consumed at cooling systems of the power plants to generate 1 GWh of electricity in 2016. In the next stage of the study, the various scenarios based on fuel types mixture are analyzed to determine the total and per generation water consumption and savings. The Long-range Energy Alternatives Planning (LEAP) program is used to determine the fuel type mixtures resulting in the minimum water consumption using optimization approaches between 2017 and 2035. Based on the comparison of the water consumption resulted in all scenarios, the wet cooling tower based scenarios have the highest amount. Whereas, the dry cooling system based scenarios achieve the lowest water consumption among the other scenarios. The scenario which assumes that the dry cooling systems are preferred more than the other systems, where available, results in reductions of 45% and 40% in 2016 and 2035, respectively.