## 7 Conclusions  
To solve the concurrent water and energy shortage issues hinder local economy, the abundant and under-utilized geothermal sources are exploited. A designed total-flow turbine (TF) from the sponsored project is applied to couple with the traditional single flash system (SF), and the combined TF-SF system is proposed and compared in this work. The performance of both power generation and water production are investigated, and a few remakes can be made as follows. 1. Under the chosen wellhead conditions, the TF-SF pattern perform better than the traditional single stage system in terms of power generation. Under a wellhead condition in which the pressure, temperature, and mass flowrate are 655.7 kPa/162.3 \({}^{\circ}\)C/14.5 kg/s, an optimum system  
Figure 7: Effects of total-flow turbine efficiency (\(\eta_{lf}\)) on TF-SF system performance. power of 851.1 kW would be reached under this condition even when the TF turbine efficiency is assumed to be as low as 35%. 2. An effective \(\eta_{\text{f}}\) of 65% can lead to an optimal power capacity of 933.0 kW, exceeding the traditional SF system by 23.7%, proving a promisingly effective combination of the total flow and single flash (TF-SF) system. 3. More than one third of total wellhead discharge can be recovered as desalinated freshwater by the naturally equipped condensation process of the power plant. This is an economical way to relieve the water shortage pressure without adding extra desalination equipment and consuming more power. G.Y. mainly contributes in methodology, investigation, validation, formal analysis and original draft preparation; Z.Y. mainly contributes in conceptualization, draft review and editing, project administration and funding acquisition. All authors have read and agreed to the published version of the manuscript. This research is funded by EPSRC (EP/P028829/1) in United Kingdom. The authors declare no conflict of interest. * Rubio and Illescas 1981 [PERSON]; [PERSON] Test of a total flow helical rotor screw expander at Cerro Prieto, Mexico. _Trans. Geotherm. Resour. Counc._**1981**, \(5\), 425-427. * [PERSON] et al. 2004 [PERSON]; [PERSON]; [PERSON], [PERSON] _An Improved System for Power Recovery from Higher Enthalpy Liquid-Dominated Fields_; Geothermal Resources Council: Davis, CA, USA, 2004; Volume 28. * [PERSON] 1993 [PERSON] Development of the Trilateral Flash Cycle System: Part 1: Fundamental Considerations. _Proc. Inst. Mech. Eng. Part A J. Power Energy_**1993**, _207_, 179-194. [CrossRef]
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