In this study, it is aimed to recover the waste heat released as a result of coal gasification and gasification with a solar reactor heat source, with an ORC integrated into the reactor. Thermodynamic analyzes for the integrated system were carried out for a solar reactor (black body solar cavity—receiver) exposed to an average solar flux concentration of 2000 and operating at 1350 K. Assumptions are given for the calculations made in both the gasification reactor and the ORC, and the results are presented in tables and graphs. In the reactor and ORC integrated design, the operation of the integrated ORC sub-cycle with high critical temperature refrigerants (R600, R113, R227ea, R365mfa, R600a, and R123) to recover the heat lost by the Q ̇uencher (evaporator) in the reactor was investigated. In this designed system, the thermodynamic analysis of the selected refrigerants for ORC was made with the EES software (Engineering Equation Solver). In the ORC system, the best energy and exergy efficiency were obtained for R123 fluid (13.93% and 11.14%), respectively.