Iman Zarinkub - M.S student, University of Guilan
Kazem Atashkari - Associate Prof, University of Guilan
Shoaib Khanmohammadi - PhD student, University of Guilan

Due to the increasing use of biomass as fuel that is cheap and renewable, the economic dimensions of this fuel needed to be studied in detail to be identified its strengths and weaknesses for using in combined cycle. In this study relied on the use of biomass in energy production and economic trends of its, a combined cycle with external combustion chamber and also has an auxiliary combustion chamber before heat exchanger, from the perspective of economic and also the effect of pressure ratio on the overall cycle costs has been studied. Fuel is used in the both combustion chamber is biomass. The results showed that the gasifier is the most important part in the exergoeconomic viewpoint and the exergoeconomic factor, which is an indication of the relative significance of exergy destruction and capital investment costs, is high for the gas turbine in the BIPFCC plant. The highest value of D ZC , which expresses the relative increase in the average cost per exergy unit between fuel and product of the component, belongs to the gasifier. Also, as the irreversibility occurring in the gasifier occurs because of the chemical reaction in this component, there is not much improvement potential in this regard. The highest Cost rate of exergy destruction is exhibited by the gasifier. It was found that increases in compressor pressure ratio leads to reduction in total unit product cost of the BIPFCC and also increases the exergoeconomic factor, but the trend is more pronounced at high values of pressure ratio. Furthermore, increases in TIT leads to reduction in the exergoeconomic factor and increases total unit product cost.

Biomass, Combined cycle, Exergoeconomic analysis