Evaluation of Gas-Steam Combined Cycle Generator Unit Using Mango Pit as Biogas
Authors: Edison E. Mojica, Sachiko C. Bautista, Pharkyn Lee O. Patriarca, Chao Wen M. Tsai
Abstract
Mango pits, considered as waste materials in the Philippine farms and which are generally thrown out, contain energy and be used as biomass with the characteristics to reduce 0.02% of the CO2 emission. In 2020, the mango production in the Philippines reached to 27.53 thousand metric tons. For the conservation of environment, the use of organic wastes such as mango pit to produce biogas was explored on this study. With most of power plant using stand-alone turbines and its efficiency reaching only 35% of the total performance, the proposed alternative energy source delivered higher efficiency and adequate power supply. The combined cycle technology of steam and gas is appropriate to work together to provide higher efficiency. The Bryton-Rankine cycle was utilized in the design and evaluation of the combined gas generator intended to achieve higher efficiency compared to the stand-alone gas turbine and stand-alone steam turbine. From the evaluation done through simulation in MATLAB of the proposed design, efficiency of the stand-alone gas turbine ranged from 20% to 35%, the stand-alone steam turbine efficiency ranged from 26% to 35%, but the efficiency of the combined cycle ranged from 35% to 55% which emphasized the increase in the efficiency of the electricity production.