Design and technical economical and environmental analyses of a hydrogen fired multi-objective cogeneration system


Durmaz A., YILMAZOĞLU M. Z. , Paşaoǧlu A.

13th International Conference on Emerging Nuclear Energy Systems 2007, ICENES 2007, İstanbul, Turkey, 3 - 08 June 2007, vol.2, pp.859-883 identifier

  • Publication Type: Conference Paper / Full Text
  • Volume: 2
  • City: İstanbul
  • Country: Turkey
  • Page Numbers: pp.859-883

Abstract

Approximately 85% of rapidly increasing world energy demand is supplied by fossil fuels. Extreme usage of fossil fuels causes serious global warming and environmental problems in form of air, soil and water pollutions. The period, in which fossil fuel reserves are decreasing, energy costs are increasing rapidly and new energy sources and technologies do not exist on the horizon, can be called as the expensive and critical energy period. Hydrogen becomes a matter of primary importance as a candidate energy source and carrier in the critical energy period and beyond to solve the energy and environmental problems radically. In this respect, the main obstacle for the use of hydrogen is the high cost of hydrogen production, which is expected to be decreased in the feature. The aim of this study is to examine how hydrogen energy will be able to be integrated with the existing energy substructure with technical and economical dimensions. In this sense, a multi objective hydrogen fired gas turbine cogeneration system is designed and optimized. Technical and economical analyses depending on the load conditions and different hydrogen production cost are carried out. It is possible that the co-generated heat is to be marketed for residence and industrial plants in the surrounding at or under market prices. The produced electricity however can only be sold to the public grid at a high unit support price which is only obtainable in case of the development of new energy technologies. This price should however be kept within the nowadays supportable energy price range. The main mechanism to be used during the design stage of the system to achieve this goal is to decrease the amortization and operational costs which lead to decrease investment and fuel costs and to increase the system load factor and co-generated heat revenues. The electricity and heat co-production capacities of the designed cogeneration system are 7 MWe and 12 MWt, respectively. Generated heat in the waste heat boiler will be supplied to the near domestic district with 500 flats for heating, cooling, and warm water supply, and to the industrial district as industrial steam. Different economical analyses are carried out for determination of electricity production cost, considering the hydrogen production technologies and different heat utilization scenarios and heat revenues. The results show that cheapest electricity generation can be realized only by combustion of hydrogen produced from natural gas. The unit electricity cost is around 0.20 $/kWhe under high system load factors and market co-generated heat revenues.