Organic Rankine Cycle (ORC) in geothermal power plants (original) (raw)
Related papers
Applications of Geothermal Organic Rankine Cycle for Electricity Production
Journal of Cleaner Production, 2020
This review deals with organic Rankine cycle powered by geothermal resource which is one favorable substitute for conventional fossil energy. Organic Rankine cycle power plants are suitable for utilization of low-temperature energy sources (low grade energy) such as geothermal resource having low temperature (below 150 ᵒC). The applications of organic Rankine cycle for electricity production from geothermal energy resource was reviewed first, where the choice of geothermal energy resources and organic fluids was discussed for different ORC configurations and operating conditions. Hybrid optimization approaches for the purpose of maintaining long term performance of enhanced geothermal system reservoirs were also summarized. Furthermore, an in-depth review of energy and exergy efficiencies of ORCs was conducted. Key factors that influence the energy and energy efficiencies of organic Rankine cycle were discussed in detail. Then, the economic indexes such as electricity production cost and levelized cost of electricity for different organic Rankine cycle configurations were compared with other conventional power generation systems to examine the commercialization of the Organic Rankine cycle. Finally, life cycle assessment that evaluates the whole life performance of geothermal organic Rankine cycle energy systems was reviewed. The Environmental impacts of geothermal ORC were also considered. Compared with other review papers on geothermal organic Rankine cycle s, the present review provides the latest materials for more systematically surveying the geothermal organic Rankine cycle, which will be a valuable source of guidance and directions for engineers and researchers in this field.
2017
A lot of heat energy can be tap to produce electricity by converting the heat and enthalpy to move a steam turbine cycle, or usually known as Rankine Cycle. But steam cycle has to have a high temperature and high enthalpy, so lower temperature and lower enthalpy source such as geothermal brine water, solar thermal, and waste heat gas cannot be tap to produce electricity. These potential belongs to ORC or Organic Rankine Cycle. ORC has no need to utilized high temperature and enthalpy, it can use temperature as low as 80oC instead of 170oC or more. By utilizing ORC system, these sources is open to produce electricity. These days a lot of research for ORC is done either by simulation or by experiment and the source is also varied. For this case, the source is geothermal brine water. The design of ORC begins with calculating the overall ORC heat balance using Cycle Tempo. Thus the duty of preheater, evaporator, turbine, condenser, pump, and cooling tower can be obtained. Then using wor...
Comparison of Enhanced Organic Rankine Cycles for Geothermal Power Units
2014
Binary cycles have drawn the attention as a technical solution for the geothermal power production. This attention is mainly due to the huge potential of medium-low temperature geothermal sources, typically exploited by means of a binary cycle, and the relevance of the environmental concern, which can be conveniently dealt with by means of a closed cycle. The binary cycle has been therefore the object of an extended research activity, in order to attain higher plant performance. A crucial matter is the improvement of the heat introduction process. For a given geothermal fluid in liquid state, i.e. for a variable temperature heat source, in a conventional ORC the working fluid evaporation process is responsible for an important second law loss: removal of this loss allows greater power and possibly higher cycle efficiency to be attained. Aim of the present paper is to investigate and compare recently proposed technical solutions based on the current technology, which do not entail co...
Organic Rankine Cycle (ORC) is a promising technology for converting the low-grade energy to electricity. This paper presents an investigation on the parameter optimization and performance comparison of the fluids in subcritical ORC and transcritical power cycle in low-temperature (i.e. 80–100 °C) binary geother-mal power system. The optimization procedure was conducted with a simulation program written in Matlab using five indicators: thermal efficiency, exergy efficiency, recovery efficiency, heat exchanger area per unit power output (APR) and the levelized energy cost (LEC). With the given heat source and heat sink conditions, performances of the working fluids were evaluated and compared under their optimized internal operation parameters. The optimum cycle design and the corresponding operation parameters were provided simultaneously. The results indicate that the choice of working fluid varies the objective function and the value of the optimized operation parameters are not all the same for different indicators. R123 in subcritical ORC system yields the highest thermal efficiency and exergy efficiency of 11.1% and 54.1%, respectively. Although the thermal efficiency and exergy efficiency of R125 in transcritical cycle is 46.4% and 20% lower than that of R123 in subcritical ORC, it provides 20.7% larger recovery efficiency. And the LEC value is relatively low. Moreover, 22032L petroleum is saved and 74,019 kg CO 2 is reduced per year when the LEC value is used as the objective function. In conclusion, R125 in transcritical power cycle shows excellent economic and environmental performance and can maximize utilization of the geother-mal. It is preferable for the low-temperature geothermal ORC system. R41 also exhibits favorable performance except for its flammability.
Combined solar-geothermal power generation using Organic Rankine Cycle
Jordan Journal of Mechanical and Industrial Engineering, 2016
This research investigates the possibility of power generation from geothermal and solar heat resources in Jordan using Organic Rankine Cycle (ORC). A comprehensive thermodynamic modelling and analysis is done in order to choose the appropriate fluid for the considered application. Fluid selection process using EES software was conducted on sixteen fluids taking into account high side and low side temperature and pressure to be the most important parameters. A step by step thermodynamic modelling with the aid of both EES and CHEMCAD software was conducted simultaneously. Several improvements have been done on the cycle to achieve the most economical and efficient design. For the selected cycle, different components were sized and defined. It was found that R600 is the most suitable fluid for application under study. The use of geothermal water as a heat source was found insufficient to generate power due to low temperature of the geothermal water. The open feed heater solar and geot...
Organic Rankine Cycle Analysis on Geothermal Based Electric Power Plant in Tulehu Village, Maluku
2020
The rapid development of technology has an impact on the increasing human need for energy, especially electricity. At present, population growth and climate change are encouraging new interest and investment in renewable energy sources to provide access to reliable and sustainable energy. One of the renewable energy sources with huge potential in Indonesia is geothermal. With the advancement of geothermal technology, low-temperature sources can be used as a source of electrical energy by using an organic Rankine cycle (ORC). The use of low-temperature geothermal sources can be an electrical energy solution for areas in Indonesia that are located still far from cheap electricity generation. In this research, a geothermal ORC plant study was conducted with a research location in Tulehu, Maluku. The source used is the TLU-01 exploration well with its geothermal fluid characteristics, namely 3 bar pressure, temperature 133.5 ° C, and debit of 238.89 kg / s. The results of this study are...