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In this study, the first time in the literature, natural zeolite has been employed for photovoltaic thermal (PVT) and experimentally tested as a thermal energy storage material. The main aim of the paper is to introduce natural zeolite as a heat storage material for PVT systems. The PVT systems integrated with phase change materials and natural zeolite were designed, the components of the system were explained, the thermodynamical modelling including the first and second laws was presented, the system performances were evaluated, performance parameters were investigated, energy and exergy efficiencies were determined, and economical analyses of each system were performed. Besides, all results were compared with a conventional PVT system. The average overall energy efficiency values for PVT experiments were 33% for paraffin, 37% for stearic acid, 40% for zeolite, and 32% for conventional PVT systems. The payback period of the PVT system with paraffin, zeolite, stearic acid, and conventional PVT was calculated as 10, 8, 9, and 9 years, respectively. The results show that the natural zeolite is a material with significant potential to be used for heat management in PVT for any meteorological condition. © 2019 John Wiley & Sons, Ltd. Türkiye Bilimsel ve Teknolojik Araştirma Kurumu, TÃœBITAK This present work was developed within the framework of a research project having ID 214M615 fully funded by The Scientific and Technological Research Council of Turkey (TUBITAK). The author would like to thank TUBITAK for the financial support given to the projects.

Although desalination market is today dominated by Seawater Reverse Osmosis (SWRO), important technological issues remain unaddressed, specifically: relatively low water recovery factor (around 50%) and consequent huge amount of brine discharged, and energy consumption (3–5 kWh/m3) still far from the minimum thermodynamic value (∼1 kWh/m3). Herein, the energy performance of an innovative systems combining SWRO, Membrane Distillation (MD) and Reverse Electrodialysis (RED) for simultaneous production of water and energy is investigated. The valorization of hypersaline waste brine by Salinity Gradient Power production via RED and the achievement of high recovery factors (since MD is not limited by osmotic phenomena) represent a step forward to the practical implementation of Zero Liquid Discharge and low-energy desalination. The analysis is supported by lab-scale experimental tests carried out on MD and RED over a broad set of operational conditions. Among the different case studies investigated, exergetic efficiency reached 49% for the best scenario, i.e. MD feed temperature of 60 °C, MD brine concentration of 5 M NaCl, RED power density of 2.2 W/m2MP (MP: membrane pair). Compared to the benchmark flowsheet (only SWRO), up to 23% reduction in electrical energy consumption and 16.6% decrease in specific energy consumption were achieved when including a RED unit. The analysis also indicates that optimization of thermal energy input at the MD stage is critical, although it can potentially be fulfilled by low-grade waste heat or solar-thermal renewable sources. Overall, the proposed integrated system is coherent with the emergent paradigm of Circular Economy and the logic of Process Intensification.

The purpose of this study is to investigate geothermal heat pump aided district heating for a town center with a population of nearly 25,000, from the exergy and economic points of view. By this way, different working fluids in a number of 12 were investigated to find the optimum solution of district heating system coupled with a geothermal heat pump system in which the geothermal resources of Simav region were directly used in a shell and tube type heat exchanger. In this aim, different system parameters such as temperature and pressure were investigated using energy and exergy analysis taking 4686 designs into consideration. The obtained results from these analysis then were evaluated from the economic aspects. For the best solution, the most economic geothermal heat pump system for district heating was revealed handling Life Cycle Cost (LCC) concept coupled with Net Present Value (NPV) analysis. It was found that it has been possible to heat the residences in a number between 7929 and 46,098 with NPV values changing between -1192.81 and 23.20 million US$. As a result, the number of 13,776 residences could be heated by using this proposed system. So, the pre-feasibility study shows that the usage of this proposed system would be an attractive investment for Simav region. © 2016 Elsevier Ltd

yapılan bir fabrikada ıslak kireçlibaca gazı desülfürüzasyon sistemi uygulamasının termodinamik ve ekonomik açıdandeğerlendirilmesi yapılmıştır. Buna göre sistem, enerji ve ekserji analizimetodları ile ele alınarak termodinamik değerlendirilmeleri yapılmış, ömür vemaliyet hesabı (LCC) ile birlikte netbugünkü değer (NBD) yöntemleri kullanılarak sistemin yatırıma değer olupolmadığı araştırılmıştır.Yapılan çalışma sonucunda, sistemin enerji verimi %48ekserji verimi %59,5 olarak hesap edilmiştir. Mevcut çalışma şartları altında,sistemin ömrü 20 yıl kabul edilerek, NBD’si2.999.727 TL olarakbulunmuş.Sistemde yapılacak iyileştirmeler neticesinde sistemin NBD’nin58.171.167 TL’ye çıkarılabileceği edilmiştir.&nbsp, In this study,the wet lime flue gas desulphurisation system (WLFGD) is considered and the wetflue gas desulphurisation system applied in a factory where the refractorybrick production is made in Kütahya province is evaluated from the termodynamicand economic point of view. The system is evaluated by energy , exergy analysismethots and thermodynamic evaluations (LCC)together with net present value (NPV) methots to determine whether thesystem is worth investment. As a result of the work done ,the energy efficencyof the system is calculated as %48 exergy efficency of system is calculated as%59,5. Under the current workingconditions, the system life has been accepted for 20 years and the investmentvalue of the system which is found as NPV 2.999.727 TL has been determined. Due to the improvements,the NPV value can be increased to 58.171.167 TL.

WOS: 000444155200012, In this study, the wet lime flue gas desulphurisation system (WLFGD) is considered and the wet flue gas desulphurisation system applied in a factory where the refractory brick production is made in Kutahya province is evaluated from the termodynamic and economic point of view. The system is evaluated by energy, exergy analysis methots and thermodynamic evaluations (LCC) together with net present value (NPV) methots to determine whether the system is worth investment. As a result of the work done, the energy efficency of the system is calculated as % 48 exergy efficency of system is calculated as % 59,5. Under the current working conditions, the system life has been accepted for 20 years and the investment value of the system which is found as NPV 2.999.727 TL has been determined. Due to the improvements, the NPV value can be increased to 58.171.167 TL.

In the present study, a novel Concentrating Photovoltaic Combined System (CPVCS) based on the spectral decomposing approach is introduced, modeled, tested experimentally and evaluated thermodynamically and economically. In this study, energy and exergy analyses of the system have been evaluated, economical analysis has been performed and the experimental results have been compared to data obtained by the control system. As a result, energy efficiencies of concentrator, vacuum tube and overall CPVCS have been determined to be 15.35%; 49.86%; and 7.3% respectively. Similarly the second law (exergy) efficiencies of concentrator, vacuum tube and overall CPVCS are 12.06%; 2.0%; and 1.16% respectively. The cost of energy production has been stated as 6.37 $/W and it is predicted that this value could be decreased by improving the system performance. © 2012 Elsevier Ltd. All rights reserved. 110M008 This study was carried out under the Scientific and Technological Research Council of Turkey (TUBITAK) 110M008 Project. The author would like to thank TUBITAK for their financial support.

Textile industry plays an important role economically in Turkey. A great amount of hot waste liquids and gases are let out in many textile processes. These waste liquids and gases have crucial energy saving potential, especially for dyeing process. It could be possible to provide energy saving by employing a waste heat recovery system (WHRS). The optimum operation conditions were assessed by integrating the first and the second law of thermodynamics for a counter flow PHE employed for a dyeing process in textile industry. The WHRS has been established by a well-known blanket manufactory located in Usak Organized Industrial Zone (UOIZ), Turkey has been evaluated. While the waste water mass flow rate varies between 8 and 12 m3/h, exergy destruction rate, exergy efficiency and effectiveness of the PHE have the values from 5.55 to 13.68 kW; from 53.6% to 67.2% and from 0.996 to 0.810, respectively. Optimum waste water and cold water mass flow rate was found as 10.00 and 7.00 m 3/h, respectively. While the cold water mass flow rate varies between 5 and 9 m3/h, exergy destruction rate, exergy efficiency and effectiveness of the PHE have the values from 8.05 to 10.89 kW; from %56.3% to %63.9% and from 0.868 to 0.991, respectively. While the waste water inlet temperatures vary between 52.4 and 59.5 °C, exergy destruction rate, exergy efficiency and effectiveness of the PHE have the values from 5.40 to 9.46 kW; from 68.7% to 61.6% and from 0.969 to 0.924, respectively at optimum mass flow rates. The present study has a great potential to serve applications of WHRS for textile application especially dyeing process. It is expected that the approach presented here would be beneficial to everyone involved in the design and performance evaluation of WHRS with PHE in many industrial sectors. It is clear that employing PHEs operating optimum conditions contribute energy savings, decrease energy cost, improve environmental impacts and shorten process period and supply economical benefits for textile industry as well as the other industrial sectors. © 2011 Elsevier Ltd. All rights reserved.