Design, technical and economical analyses of a multi-objective hydrogen-fed cogeneration system

DESIGN, TECHNICAL AND ECONOMİCAL ANALYSES OF AMULTI-OBJECTIVE HYDROGEN-FEDCOGENERATİON SYSTEM(M.Sc. Thesis)Ayşegül PAŞAOĞLUGAZİ UNIVERSITYINSTITUTE OF SCIENCE AND TECHNOLOGYDecember 2006ABSTRACTApproximately %85 of rapidly increasing world energy demand is supplied byfossil fuels. Related with this, extreme usage of fossil fuels causes globalwarming and environmental problems in the form of earth, water and airpollution. The period in which fossil fuel reserves are decreasing, energy costsare increasing and new energy sources and technologies don?t exist on thehorizon can be called as the expensive and critical energy period. Hydrogenbecomes a matter of primary importance as a candidate energy source andcarrier in the critical energy period to solve the energy and environmentalproblems radically. The aim of this study is the examination of how hydrogenenergy will be able to be integrated with the existing energy substructure bytechnical and economical dimensions. İn this sense, a multi objective hydrogen-fed cogeneration system is designed and technical and economical analysesdepending on the load conditions are carried out. İt is possible that theproduced heat is to be marketed for residence and industrial foundings undermarket prices while purchase of electricity by public at a unit support pricewhich is above the market prices beyond the scope of supporting newtecnologies is absolutely necessary. Marketing of a part of the heat produced inthe heat recovery steam generator to a residence district consisting of 500 flatsfor district heating/cooling and supplying hot water for usage purposes based onlow (below the recent marketing prices by %10) and high (above the recentmarketing prices by %20) heat sale scenarios and the remaining part of the heatto industrial foundings is projected. İt is seen from the economical analyses thatmethod of hydrogen produced from natural gas is the most convenient methodin point of economical ways. İn the cheap energy scenario, the producedelectricity at peak load conditions should be sold at least a unit price of 0,20$/kWhe and in the expensive energy scenario at a unit price of 0,16 $/kWhe. Thesale prices of electricity increase as load factor decreases. These prices are abovethe support unit price of electricity which is at about 0,12 $/kWhe producedfrom renewable energy resources in the European Union countries. Higher unitelectriciy purchase prices should be applied to have such types of designedsystems be convenient economically.Science Code : 914.1.038Keywords :Hydrogen, combined heat and power plant, gas turbine,heat recovery steam generator, economical analysesPage Number :224Adviser :Prof. Dr. Ali DURMAZ