Developing an integrated structure for simultaneous generation of power and liquid CO2 using parabolic solar collectors, solid oxide fuel cell, and post-combustion CO2 separation unit

Abstract

With decreasing underground resources and increasing carbon dioxide levels, human beings are forced to use renewable energies and new methods for power generation and CO2 elimination. In this paper, an integrated structure is developed for generating power and liquefying CO2 using parabolic solar collectors, solid oxide fuel cell, CO2 power generation cycle, separation unit, and CO2 liquefaction. This integrated structure generates 346.5 kW power, 82.2 kW heat and 158.7 kg/h liquid CO2. The hot flow outlet of the solid oxide fuel cell is used to supply the CO2 power generation cycle and enter the post-combustion CO2 separation unit. The parabolic solar collectors with climatic conditions in Tehran, Iran, are used to supply the heat of integrated structure and the ammonia-water absorption refrigeration cycle is employed to supply cooling for CO2 liquefaction. This integrated structure has a total thermal energy efficiency of 40.81% and SOFC electrical efficiency of 61.71%. Economic analysis is illustrated that the period of return and the prime cost of product are 6.26 years and 0.0855 US$/kWh, respectively. To simulate the developed integrated structure, the TRNSYS, HYSYS, and MATLAB software are used. Then, using the sensitivity analysis, the effects of fuel utilization coefficient, inlet flow temperature on gas turbine and fuel cell temperature on the performance of the integrated structure are investigated.