Author(s)

Dodeye Igbong¹, Oku Nyong^1*, James Enyia¹, Benjamin Oluwadare², Mafel Obhua³

¹Department of Mechanical Engineering, Cross River University of Technology, Calabar, Nigeria.
²Department of Mechanical Engineering, Ekiti State University, Ado Ekiti, Nigeria.
³Department of Mechanical Engineering, Nigeria Maritime University, Okerenkoko, Nigeria.

In the present study, a dual-pressure organic Rankine cycle (DORC) driven by geothermal hot water for electricity production is developed, investigated and optimized from the energy, exergy and exergoeconomic viewpoint. A parametric study is conducted to determine the effect of high-stage pressure and low-stage pressure variation on the system thermodynamic and exergoeconomic performance. The DORC is further optimized to obtain maximum exergy efficiency optimized design (EEOD case) and minimum product cost optimized design (PCOD case). The exergy efficiency and unit cost of power produced for the optimization of EEOD case and PCOD case are 33.03% and 3.059 cent/kWh, which are 0.3% and 17.4% improvement over base case, respectively. The PCOD case proved to be the best, with respect to minimum unit cost of power produced and net power output over the base case and EEOD case.

Geothermal Water, Dual Pressure Organic Rankine Cycle, Exergoeconomic Factor, Optimization

Igbong, D. , Nyong, O. , Enyia, J. , Oluwadare, B. and Obhua, M. (2021) Exergoeconomic Evaluation and Optimization of Dual Pressure Organic Rankine Cycle (ORC) for Geothermal Heat Source Utilization. Journal of Power and Energy Engineering, 9, 19-40. doi: 10.4236/jpee.2021.99002.