Thermo-economic evaluations of dual pressure organic Rankine cycle (DPORC) driven by geothermal heat source

Abstract

The thermo-economic evaluation of the dual pressure organic Rankine cycle system was presented based on the geothermal heat sources ranging from 100 to 180 °C. Two kinds of heat exchangers were selected to form four specific configuration layouts. The comparison between single and dual pressure systems was carried out. Moreover, the influence of economic parameters on cycle performance was analyzed. The electricity production cost (EPC), payback period (ppd), and saving-to-investment ratio are among the crucial considerations when the two stage evaporating pressures and pinch point temperatures are selected as independent variables. The results indicate that the dual pressure system possesses optimal EPC with the variation of low-evaporating pressure and the configuration layouts of type-FF and type-FP perform better. The cost of heat exchangers accounts for the largest proportion in the total cost of the system, followed by the expander. It can also be found that, for R1233zd, the average increasing rate of 20.87% in Wnet brings no economic benefits to the dual pressure system because the EPC also increases 12.98% averagely compared to the single pressure system. In addition, the impact of the annual loan interest rate, on-grid electricity price, and carbon tax of the system economic performance was discussed.

The Energy Storage Properties of Refrigerants (R170, R134a, R143a, and R152a) in Mof-5 Nanoparticles: A Molecular Simulation Approach

“…GCMC simulations were performed in the Sorption module of the Materials Studio. With consideration of the working conditions of refrigeration, heat pump, and ORC [42,43], the adsorption isotherms (300 K, 320 K, 340 K, 360 K, 380 K, 400 K, and 420 K) of the four refrigerants in the MOF-5 structure (Figure 1) was calculated from 1 to 4000 kPa. The fugacity was calculated by the Peng–Robinson equation.…”

Molecular Simulations of Adsorption and Thermal Energy Storage of Mixed R1234ze/UIO-66 Nanoparticle Nanofluid

“…At present, research on the thermophysical property of pure organic refrigerant is relatively mature, which can be obtained through experimental and theoretical methods. The National Institute of Standards and Technology (NIST) database [23] is widely employed in analyzing the thermophysical properties of pure fluid and thermodynamic cycles [1,2]. Thus, the thermophysical data of R1234ze was retrieved via NIST.…”

“…With the rapid development of modern society, serious problems, such as energy shortage and environmental pollution, have become increasingly prominent. Improving energy efficiency is one of the effective ways to maintain sustainable development [1,2]. Thermal cycle is the main approach for energy conversion.…”

Thermodynamic and Techno‐economic Analysis of a Triple‐pressure Organic Rankine Cycle: Comparison with Dual‐pressure and Single‐pressure ORCs

“…In addition, the thermodynamic performances of the basic, DP and DF ORCs and Kalina cycles using geothermal energy for power generation have been analyzed from energy, exergy and exergoeconomic viewpoints, respectively (Guzović et al, 2014;Shokati et al, 2015;Du et al, 2018). When choosing R1233zd as the working fluid, an average increasing rate of 20.87% in net power output (W net ) brings no economic benefits to a DP system because the electricity production cost (EPC) also increases on average 12.98% compared to a single-pressure system (SPORC) (Mosaffa et al, 2017;Wang M et al, 2018;Wang S et al, 2018). Sadeghi et al (2016) considered the net power output and turbine size parameter (TSP) as two objective functions with the aim of maximizing the first function and minimizing the second one, the results showing that STORC (series two-stage ORC) has the highest net power output.…”