Energy and exergy analyses of solid oxide fuel cell-gas turbine hybrid systems fed by different renewable biofuels: A comparative study

This paper undertakes a thermodynamic analysis of a high-temperature solid oxide fuel cell, combined with a conventional recuperative gas turbine. In the analysis the balance equations for mass, energy and exergy for the system as a whole and its components are written, and both energy and exergy efficiencies are studied for comparison purposes. These results are also verified with data available in the literature for typical operating conditions, the predictive model of the system is validated. The energy efficiency of the integrated cycle is obtained to be as high as 60.55% at the optimum compression ratio. These model findings indicate the influence of different parameters on the performance of the cycle and irreversibilities therein, with respect to the exergy destruction rate and/or entropy generation rate. The results show that a higher ambient temperature would lead to lower energy and exergy efficiencies, and lower net specific power. Furthermore, the results indicate that increasing the turbine inlet temperature results in decreasing both the energy and exergy efficiencies of the cycle, whereas it improves the total specific power output. However, an increase in either the turbine inlet temperature or compression ratio leads to a higher rate of irreversibility within the plant. It is shown that the combustor and SOFC contribute predominantly to the total irreversibility of the system; about 60 percent of which takes place in these components at a typical operating condition, with 31.4% for the combustor and 27.9% for the SOFC.

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Cycle analysis of solid oxide fuel cell-gas turbine hybrid systems integrated ethanol steam reformer: Energy management

Energy ◽

10.1016/j.energy.2017.03.105 ◽

2017 ◽

Vol 127 ◽

pp. 743-755 ◽

Cited By ~ 20

Author(s):

Dang Saebea ◽

Loredana Magistri ◽

Aristide Massardo ◽

Amornchai Arpornwichanop

Keyword(s):

Fuel Cell ◽

Solid Oxide Fuel Cell ◽

Gas Turbine ◽

Hybrid Systems ◽

Energy Management ◽

Solid Oxide ◽

Oxide Fuel ◽

Steam Reformer ◽

Ethanol Steam

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Development of a Dynamic Cathode Ejector Model for Solid Oxide Fuel Cell-Gas Turbine Hybrid Systems

Journal of Fuel Cell Science and Technology ◽

10.1115/1.4003774 ◽

2011 ◽

Vol 8 (5) ◽

Cited By ~ 4

Author(s):

James D. Maclay ◽

Jacob Brouwer ◽

G. Scott Samuelsen

Keyword(s):

Fuel Cell ◽

Solid Oxide Fuel Cell ◽

Gas Turbine ◽

Hybrid Systems ◽

Solid Oxide ◽

Theoretical Development ◽

Oxide Fuel ◽

Simulink Model ◽

Fuel Cell Cathode ◽

Good Agreement

Solid oxide fuel cell-gas turbine (SOFC-GT) hybrid systems are attractive for future power generation with ultra-low criteria pollutant and greenhouse gas emissions. One of the challenges for SOFC-GT systems is to sufficiently pre-heat incoming air before it enters the fuel cell cathode. An ejector for cathode exhaust recirculation has the benefits of reliability, low maintenance, and cost compared to either recuperators or cathode recirculation blowers, which may be also be used for air pre-heating. In this study, a dynamic Simulink model of an ejector for cathode exhaust recirculation to pre-heat incoming fuel cell air has been developed. The ejector is to be utilized within a 100 MW SOFC-GT dynamic model operating on coal syngas. A thorough theoretical development is presented. Results for the ejector were found to be in good agreement with those reported in literature.

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