Economic analysis and optimal capacity sizing of turbo-expander-based microgrid
These days, extensive efforts are being carried out to improve energy efficiency and energy recovery in various energy systems, such as extraction of energy from the high-pressure natural gas (NG) in pressure reduction stations (PRSs) employing a turbo-expander (TE). In conventional PRSs, NG pressure reduction is carried out by pressure regulators, leading to the loss of mechanical exergy available in the pressurised NG as heat. Thus, replacing a pressure regulator with TE allows the extraction of the mechanical exergy to change into electrical form of energy by coupling with a generator. So, a novel configuration is presented here for grid-connected microgrid based on TE. Furthermore, a new procedure is developed for optimal capacity sizing of energy resources in the proposed TE-based microgrid. Finally, optimisation results (with and without TE) and economical considerations are discussed.