Sustainability is one of the challenging issues in electricity production systems.
Recently, solid oxide fuel cell (SOFC) has been suggested for use in combined heat and
power (CHP) systems. This application is introduced as a promising
environmentally-friendly system according to the thermodynamic and electrochemical models.
In this paper, an atmospheric SOFC/CHP cycle was analysed based on integrating exergy
concepts, energy and mass balance equations. In this regard, a zero-dimensional energy and
mass balance model was developed in engineering equation solver (EES) software. Two
dimensionless parameters (the exergetic performance coefficient (EPC) for investigating
the whole cycle, and exergetic efficiency for investigating the exergy efficiency of the
main component of this cycle) were applied. Results show that efficiencies of the system
have been increased substantially. The electrical efficiency, total efficiency and EPC of
this cycle were ~54%,
~79% and
~58% respectively.
Moreover, the CO2
emission is 19% lower than when compared with a conventional combined power cycle fed by
natural gas. In addition, a dynamic economic evaluation was performed to extract the most
sensitive parameters affecting the outputs: electricity sales price (ESP), equipment
purchase cost and fuel cost. Furthermore, an electricity production cost of
~125 $
MW.h-1 was
attributed to our model, resulting in yet further cost reduction for widespread
applications of this cycle.