Akademik Veri Yönetim Sistemi
Tezin Türü: Doktora
Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Mühendislik Fakültesi, Makina Mühendisliği Bölümü, Türkiye
Tezin Onay Tarihi: 2015
Öğrenci: ENDER ÖZDEN
Danışman: İLKER TARI
Özet:A hybrid (Solar-Hydrogen) renewable energy system consisting of Photovoltaic (PV) panels, Proton Exchange Membrane (PEM) fuel cells, PEM based electrolyzers and hydrogen storage has been investigated for a stand-alone application. A complete model of the hybrid renewable energy system has been developed using TRNSYS against a reference system, which was established for the emergency room of Keçiören Research and Training Hospital in Ankara. The main goal of the study is to verify that the system meets the electrical power demand of the emergency room without any shortage for a complete year. The emergency room has a peak electrical load of 5 kW and a yearly load of 37.23 MWh. The PV panels with a total area of 300 m² are mounted on a tiltable platform to improve the performance of the system. The PEM fuel cells have a total capacity of 5 kW. The hydrogen storage pressure is 55 bars with the capacity of 30 m³. Energy and exergy analyses of the system are performed together with a detailed economic analysis. The PEM fuel cells are numerically modeled in ANSYS Fluent in order to obtain data for the TRNSYS model. The obtained simulation data is used both for the PEM fuel cells and the PEM based electrolyzers. The developed numerical model later modified to include cell degradation. Again, using the data from the degraded model, the TRNSYS model is updated and the performance of the system after two years of operation is predicted. After the performed analyses, it is concluded that solar-hydrogen based renewable energy systems can be a possible alternative to fossil fuel based energy systems especially in long-term emergency blackout conditions. Furthermore, it is determined that the system is capable of continuously working throughout a whole year when the hydrogen storage capacity is increased to 45 m³ and the overall efficiency of the system is improved by using variable angle of incidence for the PV panels. Additionally, it is concluded that the degradation of PEM based system components is an important phenomenon, which has detrimental effects on the overall system performance.