Modeling and optimization of a novel Oxy-fuel/Solar/Wind/Battery power generation system

Abstract

• The optimized combined system can perfectly meet the needs of electricity grid. • The cold energy of LNG is used to condense CO 2 and nearly zero CO 2 emissions is achieved. • The optimal model is obtained by considering various wind-solar ratios and scales of battery storage capacity. • The LCOE of the combined system is reduced by 3% to 6% with the employment of solar-wind energy. It is proposed and built a novel oxy-fuel/solar/wind/battery power generation system. It consists of a solar-wind renewable system (SWRS) with battery bank and a liquefied natural gas-fueled oxy-fuel combined cycle (OFCC). The work is unique in that it uses SWRS to power OFCC’s main energy-consuming equipment, such as the recycled CO 2 compressor (RCC) and air separation unit (ASU). SWRS power is consumed locally, avoiding the negative effects of SWRS intermittency and variability on the electricity grid. CO 2 is compressed, cooled and then condensed by evaporating the cold LNG. MATLAB/Simulink and Aspen Plus were used to create the SWRS and OFCC, respectively. In order to find the optimal model of the combined system in terms of economic factors, various wind-solar ratios, scales of SWRS and OFCC, and battery storage capacity have been considered and combined. The results show that the optimized combined system can perfectly meet the needs of the electricity grid while having a high renewable energy utilization efficiency, no negative impact on power grid stability, low power generation costs, and low CO 2 emissions. This work will serve as a guide for the combined power system’s power supply planning.