Thermodynamic Simulation Modelling of Low Temperature Geothermal Source Located in Arid-Zone Areas of North Africa

This paper presents a thermodynamic modelling study of the utilization of an existing geothermal low-temperature heat source (114 kg/s and 73 ºC) situated at Waddan city in Libya. Six models have been built and simulated using both IPSEpro refrigeration and power plant modelling libraries. All the models were validated in accordance to published literature and relevant fundamental thermodynamic tables and graphs. Results of five models have shown that the community in Waddan city could benefit from the geothermal source. For instance these models could provide 1284 ton of refrigeration at 5 ºC, for air-conditioning use, or 835 ton of refrigeration at 0ºC or 1324 kW of direct generated electricity. The sixth model has proved that this sustainable geothermal source could support a local electrical power station consisting of a natural gas fired turbine unit combined with an organic Rankin cycle. This station will provide Waddan city and surrounding villages with their demand of electrical and thermal energy of about 128MW (GT 85MW, ORC 18MW and District heating 25 MW at 75 ºC).