Double Flash Cycle Research Articles

Multi-criteria thermoeconomic optimization of a geothermal energy-driven green hydrogen production plant coupled to an alkaline electrolyzer

Among the various technologies for hydrogen production, the renewable energy driven water electrolysis has emerged as a favorable method. In this respect, the present research proposes and analyses a novel and efficient medium-temperature driven geothermal system for green hydrogen production. An alkaline electrolyzer is deployed for hydrogen production which is powered by a double flash steam geothermal power cycle. To boost the power generation (and hence the hydrogen production amount) the double flash cycle is equipped with a self-superheating process, which superheats the saturated vapor at turbine inlet without using another external heat source. Thermodynamic evaluations, based on exergy concept, along with economic analysis are carried out to assess the hydrogen production amount, plant exergy efficiency and total cost rate, and the unit hydrogen price. In order to represent a comprehensive investigation of the plant performance, parametric analyses along with single- and multi-criteria optimizations were conducted. The results revealed that, for 1kg/s of geothermal brine, the capacity of hydrogen production of the proposed plant is ∼1.5−3kg/h under various operating conditions. It is found that, under multi-objective optimum operating conditions, the plant yields 12.63% exergy efficiency and its total cost rate is calculated to be 10.42 $/h. However, if the plant is to be optimized for maximum exergy efficiency, the value of 14.25% is achievable which will result in increment of total cost rate to 11.97 $/h.

Thermodynamic model-based specification of optimal geothermal power generation system for high-temperature liquid-dominated systems using flash and flash-binary cycles

The utilization of high-temperature geothermal fluid for power generation requires the most suitable generation system to maximize the output with the highest efficiency. Single-flash, double-flash, and flash-binary cycles are the most representative systems for a reservoir with high-temperature geofluids. This study aims to develop a thermodynamic model-based method for selecting the optimal power generation system using criteria of power output and energy and exergy efficiencies. For this purpose, a thermodynamic model of the power generation system was constructed to calculate these values for high-temperature geofluids at 230–350 °C under steady-state conditions. The critical thermodynamic parameters that control these criteria include the separator pressure for the single and double flashers, working fluid, turbine inlet pressure, brine outlet temperature, and pinch point temperature, all of which are incorporated into the calculation. The results show that the flash-binary cycle generates the highest power; 21% higher than that of a single-flash cycle at the 5 °C pinch point, and 7% higher than a double-flash cycle. In addition to this merit, a cautious temperature of 120 °C is recommended for the cold reinjection fluid of a flash-binary cycle, which is considerably lower than that for the single- and double-flash cycles (164 °C).

Conventional and advanced exergy investigation of a double flash cycle integrated by absorption cooling, ORC, and TEG power system driven by geothermal energy

This study looked at both conventional and advanced exergy analyses of a new combined cooling, heating and power generation system driven by geothermal energy. This cycle consists of a double flash cycle with two thermoelectric generator units and an organic Rankine cycle, besides Li–Br/water absorption cooling cycle. A parametric investigation is performed to indicate the influence of flash cycle pressures and also turbine inlet temperature on the system performance. To evaluate the accurate potential for improving this cycle performance, the first and second-division levels of exergy destruction are determined. In this study, the thermodynamic cycle approach of advanced exergy analysis is used to identify different parts of exergy destruction for each system component. Under real and unavoidable conditions, the system's overall exergy efficiency is 53.38% and 55.83%, respectively. Based on the entire avoidable exergy destruction rate, the system's greatest improvement potential is 9732.4 kW (about 35.35% of total exergy destruction), that 60.01% of this avoidable value being endogenous and 39.99% of avoidable part being exogenous. It is also disclosed that the prioritized order of components acquired by conventional exergy analysis differs from that obtained by advanced exergy analysis for increasing overall system performance. The TEG1, the generator, the TEG2, the LPT, and the condenser1, …are recommended by the conventional, whereas the generator, the LPT, and the absorber, …are recommended by the advanced exergy analysis. Despite having the largest exergy destruction, the data show that the TEG1 seems to have moderate improvement potential.

Flash evaporation strategy of organic Rankine cycle for geothermal power performance enhancement: A case study

The performance of organic Rankine cycle (ORC) is poor due to the high irreversible losses in evaporator. To improve system performance, organic Rankine single flash cycle (ORSFC) and organic Rankine double flash cycle (ORDFC) are proposed, in which the traditional evaporation process is split into incomplete evaporation and flash evaporation. Thermal and exergetic efficiencies are taken as the objective functions, and the effects of the related operating parameters and the number of the flash stage on the thermodynamic performance of the system is conducted. The results show that for the ORSFC and ORDFC, in the direction of the rise of the heat source temperature, the net power output increases, the optimal evaporation temperature and flash temperature corresponding to different performance criteria also gradually increase. Besides, the dryness of the evaporator outlet is inversely proportional to the net power output, while it is directly proportional to the system efficiencies. When the dryness increases by 0.1, the net power output of the ORSFC and ORDFC decreases by an average of 148.5 kW, the thermal efficiency and exergetic efficiency of the ORSFC and ORDFC increase by an average of 0.56% and 1.37%, respectively. Moreover, with the flash stages increase, the performance criteria are improved at different magnitude. When a specific thermodynamic parameter is optimized, the ORDFC always obtains the best value for this parameter.

Combination of a geothermal-driven double-flash cycle and a Kalina cycle to devise a polygeneration system: Environmental assessment and optimization

Geothermal systems have a low carbon footprint and are eco-friendly. Therefore, the present study lays bare the fact that the waste heat from a geothermal-driven double-flash cycle can be efficiently recovered by a Kalina cycle and a thermoelectric generator. The Kalina cycle, in turn, has heat loss that is recovered by an LiCl-H2O absorption chiller and another thermoelectric generator. The favorable electricity is produced by the low-pressure turbine of the double-flash cycle. The output power of the high-pressure turbine of the double-flash cycle is consumed in an electrolysis unit to produce hydrogen, and the electricity generated by the Kalina cycle is responsible for freshwater production in a reverse osmosis system. The exergy efficiency and unit cost of the products of the system are obtained as 35.58 % and 9.512 $GJ-1 at the optimal point, which are proper values regarding the production of hydrogen and freshwater in the system. In addition, the payback period of the system is 0.418 years, which is an excellent value. The high economic performance of the system is rooted in the low unit cost of the products of the double-flash cycle, which makes it a suitable choice to be employed as the topping cycle of such polygeneration systems. Finally, sustainability index and CO2 emission rate at the optimim point are equal to 1.552 and 6.27 tone/day, respectively.

Exergo-economic and exergo-environmental evaluations and multi-objective optimization of a novel multi-generation plant powered by geothermal energy

An innovative multi-generation energy system is proposed to generate simultaneous power, drinking water, cooling, heating, and H2. The aimed plant comprised of an absorption chiller, a heat pump unit, a reverse osmoses unit, a double flash cycle, and a proton exchange membrane. The devised system is surveyed comprehensively based on the thermodynamic, thermo-economic, and exergoenvironmental indicators for offering an in-depth assessment of the plant. Besides, multi-objective optimization has been employed in the proposed system. The net proportions of output work, unit cost, thermal and exergetic efficiencies, and H2, and purified water production of the system are 99.25 kW, 124 $/GJ, 24.4%, 32.1%, 1.218 kg/h, and 0.9662 kg/s, separately. The outcomes related to thermodynamic and thermo-economic evaluations demonstrate that the greatest amount of total cost rate occurred in the first employed turbine. Owing to the findings of the parametric study, by increasing geothermal temperature, exergoenvironmental parameters are reduced, and with increasing the pressure of FT1, cooling load and energetic efficiency increase while SUCP, net output work, and exergetic efficiency decrease dramatically.

Energy, Exergy, Exergoeconomic and Exergoenvironmental Impact Analyses and Optimization of Various Geothermal Power Cycle Configurations.

Energy, exergy, and exergoeconomic evaluations of various geothermal configurations are reported. The main operational and economic parameters of the cycles are evaluated and compared. Multi-objective optimization of the cycles is conducted using the artificial bee colony algorithm. A sensitivity assessment is carried out on the effect of production well temperature variation on system performance from energy and economic perspectives. The results show that the flash-binary cycle has the highest thermal and exergy efficiencies, at 15.6% and 64.3%, respectively. The highest generated power cost and pay-back period are attributable to the simple organic Rankine cycle (ORC). Raising the well-temperature can increase the exergy destruction rate in all configurations. However, the electricity cost and pay-back period decrease. Based on the results, in all cases, the exergoenvironmental impact improvement factor decreases, and the temperature rises. The exergy destruction ratio and efficiency of all components for each configuration are calculated and compared. It is found that, at the optimum state, the exergy efficiencies of the simple organic Rankine cycle, single flash, double flash, and flash-binary cycles respectively are 14.7%, 14.4%, 12.6%, and 14.1% higher than their relevant base cases, while the pay-back periods are 10.6%, 1.5% 1.4%, and 0.6% lower than the base cases.

Effects of two-phase expander on the thermoeconomics of organic double-flash cycles for geothermal power generation

The use of a two-phase expander in place of the throttling valve can improve the organic double-flash cycle (ODFC) thermal efficiencies. This work compares the thermoeconomics of a regenerative ODFC (RODFC), an expander-ODFC (EODFC) and a double expander-ODFC (DEODFC). The evaporation and flash temperatures of these cycles are optimized to maximize the net power outputs for geofluid temperatures of 120–180 °C. The results show that the two-phase expander in EODFC leads to the lowest optimal first-stage flash temperature with the highest vapor mass flow rate for the high-pressure turbine. The power generated by the two-phase expanders in DEODFC is less than that generated by the expander in EODFC but the power generated by the turbines is 5.9–8.4% higher. DEODFC produces the maximum net power, followed by EODFC and RODFC for each geofluid temperature. The exergy losses during evaporation are reduced by up to 41% by regeneration in RODFC, EODFC and DEODFC. The two-phase expanders increase the exergy losses during power generation but decrease the losses during throttling and condensation; thus, the exergy efficiency of DEODFC increases to 32.8–46.8%. The levelized cost of electricity for DEODFC is 15–33% lower than for ODFC due to the great increase in the net power output.

Exergy Analysis Using a Theoretical Formulation of a Geothermal Power Plant in Cerro Prieto, México.

The purpose of this research is the calculation of the exergy destruction of the single-flash and double-flash cycles of a geothermal power plant located on the ladder of the 233 m Cerro Prieto volcano, on the alluvial plain of the Mexicali Valley, Mexico. The methodology developed in this research presents thermodynamic models for energy and exergy flows, which allows determining the contribution of each component to the total exergy destruction of the system. For the case-base, the results indicate that for the single-flash configuration the efficiency of the first and second law of thermodynamics are 0.1888 and 0.3072, as well as the highest contribution to the total exergy destruction is provided by the condenser. For the double-flash configuration, the efficiency of the first and second law of thermodynamics are 0.3643 and 0.4983. The highest contribution to the total exergy destruction is provided by the condenser and followed by the low-pressure turbine.

Life cycle assessment of a geothermal combined heat and power plant based on high temperature utilization

This study applies life cycle assessment (LCA) to examine environmental impacts of generating 1 kW h of energy in a geothermal combined heat and power (CHP) plant based on high temperature geothermal utilization. The Hellisheidi geothermal CHP plant located in SW Iceland, producing 303 MWe and 133–267 MWth in a double flash cycle, is used as a case study for the LCA. The CML-IA baseline and Cumulative Energy Demand (CED) methods are used to perform the life cycle impact assessment (LCIA), providing results for common environmental impact categories investigated in most LCA studies. The impacts associated with joint production processes for electricity and heat are allocated to the two products by energy allocation. The result show that the construction phase of the plant, mainly drilling and casing of geothermal wells along with construction of collection system for geothermal fluid, is largely responsible for most of the impact category results. However, the global warming potential (GWP100), acidification (AP) and the renewable cumulative energy demand from wind, solar and geothermal energy (CEDR,w,s,g) are mainly affected by the operational phase of the plant, due to direct emissions of gases (mainly CO2 and H2S) and the extraction of geothermal fluid from ground. To explore the effects of currently installed mitigation methods and operational improvements at the Hellisheidi plant, two operation scenarios are investigated within the study; the first based on a previously published dataset for operating conditions at year 2012 and the second, an updated dataset based on inclusion of implemented mitigation methods until the operating year 2017. Due to carbon capture and storage (CCS) by reinjection of CO2 using the CarbFix method developed at Hellisheidi, the GWP100 reduced from 15.9 g CO2eq/kWh to 11.4 g CO2eq/kWh for electricity and 15.8 g CO2eq/kWh to 11.2 CO2eq/kWh for heat over the 30-year operational time under investigation. Similarly, the SulFix method used for reinjection of H2S at Hellisheidi resulted in decreased AP from 9.7 g SO2eq/kWh to 3.6 and 3.5 g SO2eq/kWh and human toxicity (HTP) from 5.8 and 5.5 g 1,4-DB eq/kWh to 5.1 and 4.8 1,4-DB eq/kWh for electricity and heat respectively. The overall CED resulted in 5.2 kW h (18.7 MJ) of energy demand to produce 1 kW h of either electricity or heat, dominated by the use of geothermal energy as mentioned earlier. Non-renewable energy demand (CEDNR) decreased from 6.8 × 10−3 and 5.9 × 10−3 kWh (0.024 and 0.021 MJ) to 5.8 × 10−3 and 5.0 × 10−3 kWh (0.021 and 0.018 MJ), for electricity and heat respectively, by using electrical drills instead of diesel fueled drills for additional wells during the operational time of the power plant. In conclusion, these results indicate a very high environmental performance of the Hellisheidi plant compared to other energy conversion technologies and emphasizes the potential of geothermal energy as a clean energy source for producing electricity and heat.

Thermodynamic simulation and mathematical model for single and double flash cycles of Cerro Prieto geothermal power plants

Geothermal power generation technologies are well established and there are numerous power plants operating worldwide. The Cerro Prieto geothermal field is located in northwestern Mexico, approximately 32 km from the US-México border. A single flash and double flash cycle have been selected for power generation. The study is aimed to thermodynamic simulation and mathematical model development for the single and double flash cycles. Thermodynamic Simulation for energy flows were developed and implemented in Aspen Hysys software, while the multiple linear regression analysis was developed in IBM SPSS software. The single flash cycle thermodynamic simulation of the proposed design shows the plant’s maximum net power output can reach 36.667 MW if the separator and condenser pressures are 650 kPa and 11.5 kPa, respectively. In the double flash cycle, the optimum pressure value for high pressure (HP) separation is 1200 kPa, low pressure (LP) separation is 385 kPa and the pressure for condenser was determined to be 11.5 kPa, the maximum net power output of the plant is 102.112 MW. The multiple linear regression shows mathematical model to predict the net power and thermal efficiency for single flash and double flash cycles, using the independent variables of the well temperature, separator pressure and condenser pressure to obtain a mathematical expression that predicts the behavior of this cycle. While for the double flash cycles, the well temperature, the pressures in the separators and the condenser pressure are used. The mathematical models to predict the net power and the thermal efficiency of the cycles shows a very good approximation to the thermodynamic analysis, the single flash cycle shows ANOVA results net power (r=0.999885, R2=0.999769, p<0.0001) and thermal efficiency (r=0.999628, R2=0.999256, p<0.0001), while the double flash cycle ANOVA results net power (r=0.999861, R2=0.999722, p<0.0001) and thermal efficiency (r=0.999806, R2=0.999612, p<0.0001).

Energy and Exergy Analysis of a New Power, Heating, Oxygen and Hydrogen Cogeneration Cycle Based on the Sabalan Geothermal Wells

In this paper, a new power, heating and hydrogen cogeneration cycle from Sabalan geothermal two wells is proposed and analyzed. In the proposed system, a new double flash cycle and organic Rankine cycle are used for power production. A proton exchange membrane (PEM) is also used for hydrogen production and the domestic water heater is used for heating. The impacts of some design parameters, such as separators pressures, evaporator temperature, pinch point temperature difference and PEM temperature on the integrated system performance are investigated and then optimization is done from exergy point of view for three considered scenarios. According to the optimization results, the value of heating, net output power, hydrogen production and thermal and exergy efficiencies of the cogeneration system are obtained as 15751 kW, 18436 kW, 11.13 kg/h, 29.48% and 65.23%, respectively.

Cycle improvement and hydrogen steam superheating at Mutnovsky geothermal power plant

This study is aimed at a possibility of hydrogen production and hydrogen steam superheating at a single-flash 50 MW Mutnovsky geothermal power plant stage 1. A modification by introduction of a low-pressure single-flash unit utilizing energy of the separated liquid is proposed, and the integrated single- and double-flash cycle is analyzed. The second flash process gives a maximum possible increase of the installed capacity on 11.1 MW for the flash temperature of 92 °C, and 9 MW for 120 °C. Currently the plant does not use 12.3% of the geothermal steam for electricity generation, partly due to demand side management from a grid operator. Excess power can be used for water electrolysis and for each 1% of saved steam 92 t of H2 can be produced annually. Hydrogen combustion in a high temperature hydrogen-oxygen steam generator can be used for steam superheating in a second flash process, achieving the increase of steam temperature at the low pressure turbine inlet by 20–30 K, and an increase of steam dryness at the turbine outlet by 2–4%. Additional available power rises by 5–10% (0.5–0.9 MW) and overall thermal efficiency of the plant can be increased from 10% to 12.5%.

A comparative study and optimization of enhanced integrated geothermal flash and Kalina cycles: A thermoeconomic assessment

This work deals with a comparative study for different basic and enhanced integrated geothermal flash and Kalina cycles from the thermoeconomic point of view. The considered cycles include different combination of basic and modified Kalina cycles, basic geothermal single flash cycle, double flash cycle and its enhanced modes. The basic Kalina cycle is modified by employing a two-phase expander instead of the throttling valve. Also, in order to enhance geothermal flash cycle, the geofluid steam is heated by a part of the heat contained in the geofluid at the wellhead before entering the turbine. Moreover, the effects of different key parameters on the thermodynamic and economic performances are investigated and optimized using the genetic algorithm method. The results show that when enhanced double flash/modified Kalina cycle is used, generated power increases by 6% compare to the basic cycle under the optimum operating condition. In this case, the increment of unit production cost is ignorable compared to the basic cycle. The exergy destruction rate of each component is calculated under the optimum operating condition. For all considered cycles, the highest value of exergy destruction rate belongs to the evaporator.

Exergoeconomic analysis and optimization of single and double flash cycles for Sabalan geothermal power plant

In this study single and double flash systems were designed to utilize the Sabalan geothermal fluid as a heat source. An Exergoeconomic model was applied on plant’ equipment in order to calculate the thermodynamic and economic performances of the cycles. Parametric analysis was done to examine the effect of important key parameters including flash pressures and steam quality at turbine outlet on plant performance. Optimization process for maximum net power output was carried out on the plant using direct searching method in EES (Engineering Equation Solver). This process aimed to find the optimum flashing pressures corresponding to the maximum potential power output as an objective function. Additionally, the major exergy destruction locations were shown graphically and side by side for both systems to observe the effect of secondary flash process on exergy destruction at each component. Afterward, an environmental study was done in order to calculate the amount of fossil fuel saving and pollutants emission reduction compared to conventional fossil fuel power plants. The result showed that in double flash energy and exergy efficiency were increased from 16.26% and 40.06% to 17.73% and 50.89%, respectively. Moreover, double flash resulted in higher net power output compared to that of single flash (28,838kW vs. 36,055kW) while both cycles were using the same geofluid. Optimization results revealed that thermodynamically optimum cycle could not result the best and lower energy production cost and vice versa. Therefore, the single flash generates electricity within lower price compared to double flash system. Moreover, double flash considerably reduces the required fossil fuel and various pollutants emission more than single flash if they were replaced by fossil fuel power plants with same amount of production.

A comprehensive comparison among different types of geothermal plants from exergy and thermoeconomic points of view

In present study, some chosen cycles of the geothermal power plant, such as dry steam cycle, single, double and triple flash cycles and different configurations of the organic Rankine cycle have been investigated and compared with each other using energy, exergy and thermoeconomic analyses. Effective parameters on efficiency and exergy destruction, such as flash pressure in flash cycles and extraction steam pressure in organic Rankine cycles have been optimized and the optimized conditions have been used for economic analyses. Results of the thermodynamic analysis show that the dry steam cycle has the maximum energy and exergy efficiency among all the considered systems in current study. Furthermore, the results show that the power capacity in double flash cycle is 27.7% higher than that in single flash cycle and also the triple flash cycle generates 10% more power than the double flash cycle. Despite of the acceptable performance of the triple flash cycle from thermodynamic point of view, the obtained results from thermoeconomic analysis indicates that using this system is not cost effective. Moreover, when a same value for geofluid inlet exergy is considered for all the systems mentioned in present work, the results of analysis emphasize that the dry steam cycle is the best system from thermoeconomic point of view, followed by the single flash and double flash cycles.

A meta-study of the effect of thermodynamic parameters on the efficiency of geothermal power plants worldwide

As global energy demand rises, the search for viable alternative fuel sources continues. The practicality of geothermal energy to meet this demand is highly dependent on optimizing thermal efficiency. While geothermal energy is currently used in places like Western Australia for direct-heat applications such as leisure centres, developing a geothermal power plant in such an area depends on predicting which thermodynamic parameters optimize thermal efficiency. This meta-study focuses on the effect of geothermal operation parameters such as inlet pressure, temperature, mass flow rate, well depth and number of production wells on the thermal efficiency of geothermal power plants. Drawing data from 61 geothermal power plants around the world ranging in design capacity (MWe) and size, a meta-study on the thermal efficiency of plants operating under different thermodynamic cycles, namely single-flash, double-flash, binary Organic Rankine Cycle (ORC) and Kalina, is offered. These various thermodynamic parameters are analysed to determine the presence of observable thermal efficiency patterns or trends that may lead to the optimization of operation parameters for new geothermal plants. Based on the available published data reviewed, there are few trends which indicate how geothermal operation parameters affect thermal efficiency. Well depth may be an indicator of efficiency for geothermal power plants using ORC and double-flash cycles, however further data is required to support this conclusion.

Comparative and parametric study of double flash and single flash/ORC combined cycles based on exergoeconomic criteria

In this study, double flash geothermal power cycle and single flash/ORC combined cycles with different organic fluids are used for power generation from geothermal fluid reservoir with given temperature. n-heptane, R141b, R113 and steam are selected as organic working fluids in ORC and NH3 is used as a reference working fluid in ORC in this study, as it is a common working fluid in geothermal power plants and Kalina. After energy and exergy analyses of the mentioned cycles, a comprehensive exergoeconomic analysis by developing cost balance and auxiliary equations for all components of the cycles using SPECO approach is done and all exergoeconomic parameters are calculated and these cycles are compared from thermodynamic and exergoeconomic viewpoints. Also a parametric study is performed and the effects on the thermodynamic and exergoeconomic performance of the considered cycles of such operating parameters as separator pressures in double flash geothermal power cycle and separator pressure and evaporation temperature in single flash/ORC combined cycles. The results show that although the highest values of first law efficiency and exergy efficiency among the mentioned cycles are related to single flash/ORC with steam but the minimum unit cost of produced power is related to double flash cycle. Also according to parametric study, with increasing evaporation temperature in single flash/ORC the value of C˙D,tot+Z˙tot parameters for all combined cycles except single flash/ORC with ammonia increases continuously.

Thermodynamic and economic analysis and optimization of power cycles for a medium temperature geothermal resource

Geothermal power generation technologies are well established and there are numerous power plants operating worldwide. Turkey is rich in geothermal resources while most resources are not exploited for power production. In this study, we consider geothermal resources in Kutahya–Simav region having geothermal water at a temperature suitable for power generation. The study is aimed to yield the method of the most effective use of the geothermal resource and a rational thermodynamic and economic comparison of various cycles for a given resource. The cycles considered include double-flash, binary, combined flash/binary, and Kalina cycle. The selected cycles are optimized for the turbine inlet pressure that would generate maximum power output and energy and exergy efficiencies. The distribution of exergy in plant components and processes are shown using tables. Maximum first law efficiencies vary between 6.9% and 10.6% while the second law efficiencies vary between 38.5% and 59.3% depending on the cycle considered. The maximum power output, the first law, and the second law efficiencies are obtained for Kalina cycle followed by combined cycle and binary cycle. An economic analysis of four cycles considered indicates that the cost of producing a unit amount of electricity is 0.0116$/kWh for double flash and Kalina cycles, 0.0165$/kWh for combined cycle and 0.0202$/kWh for binary cycle. Consequently, the payback period is 5.8years for double flash and Kalina cycles while it is 8.3years for combined cycle and 9years for binary cycle.

Self-Superheating: A new paradigm for geothermal power plant design

In this paper, a new thermodynamic concept for improving the Single-Flash and the Double-Flash cycles in geothermal power plants is presented. This process, named Self-Superheating, uses a part of the heat contained in the geothermal fluid at the well-head to increase the temperature of the steam that enters the turbines. When optimal separator temperature is used, the results of this novel process are an increase of the specific output (approximately 5%) of the geothermal power plant and a reduction (approximately 20–40%) of the liquid content in the last stages of the turbines. The optimal separator temperature for the cycles using Self-Superheating is about 5°C lower than the optimal separator temperature of the Single-Flash and Double-Flash cycles. The simple but fundamental process of Self-Superheating opens the route for more complex thermodynamic cycles in geothermal power plants.