Abstract
Hot spring thermal energy is a low enthalpy energy source, which is able to apply to extract the electrical energy converting by a heat engine. The power generation systems utilized the heat source of finite temperature and finite flow rate have unique characteristics that the maximal condition of thermal efficiency does not correspond to the condition of maximum power generation point. However, such thermodynamic theory has not introduced for the estimation and evaluation of the power generation in hot spring thermal energy. Therefore, for the evaluation and the development of the system, this paper shows the theoretical maximum available energy based on finite-time thermodynamics and proposes the generalized evaluation methods on the power generation system. Moreover, the parametric analysis is conducted using HFC245fa and HCFO1224yd(Z) to consider the adaption of low global warming potential working fluid on ORC system. The results clarified the effectiveness of the evaluation method and the possibility of equivalent power generation using HCFO1224yd(Z) as the alternate material as the working fluid.
