Parametric layout and performance examination of a novel energy process based on the renewable energies and thermodynamic cycles

Abstract

Today, due to the challenges of fossil fuels and environmental crises, the use of geothermal energy as a renewable energy source can be useful. Since the two wells used for Sabalan geothermal power plant have different thermodynamic, in the present article, a new combined layout based on two flash cycles is proposed and investigated. In the introduced energy cycle, the transcritical Rankin and Kalina cycles are also used as downstream cycles to generate more power. In addition, heat exchangers are used to transfer heat to the liquefied natural gas (LNG) cycle to prevent energy and exergy losses in the downstream cycles. Relying on the proposed layout can prevent heat loss of downstream cycle's condensers. LNG cycle, in addition to generating more power by using heat losses, can supply natural gas to the system and suburban villages. It was determined that the proposed energy cycle is able to produce a net power of ~27.8 MW with a thermal efficiency of ~26%. In addition, the total exergy destruction and exergy efficiency of the cycle are 29.9 MW and 52.6%, respectively. The proposed energy cycle is evaluated from the energy and exergy points of view. In addition, a parametric evaluation is presented to assess the effect of various factors on the performance of the proposed energy cycle. Moreover, the net power and performance of the energy cycle have been optimized subject to various input variables using a genetic algorithm.