EFFECT OF EVAPORATION PRESSURE ON THE PERFORMANCE OF A CLOSED CYCLE OTEC USED FOR ELECTRICITY IN NIGERIA

Abstract

The study of the effect of evaporation pressure on the performance of a closed cycle OTEC used for electricity in Nigeria has been performed. Fundamental thermodynamic principles will undergird the governing equations, with detailed analyses performed using advanced simulation software tools like ASPEN HYSYS and MATLAB was employed. The simulations were performed using MATLAB v8.5a and Aspen Hysys v11 software, employing various input conditions such as sea surface water temperatures, pressures, mass flow rates, cooling water temperatures, and pressures. It was observed that as the evaporation pressure increases from 800 KPa to 1000 KPa: in the Hysys simulation, the net power output increases from 14.88 KW to 28.76 KW, while in the MATLAB simulation, it increases from 15.08 kW to 28.93 kW; The efficiency increases from 39.15% to 40.02% in the Hysys simulation and from 39.16% to 40.03% in the MATLAB simulation and the evaporator heat duty also increases, from 1133 kW to 1173 kW in the Hysys simulation and from 1134 KW to 1175 KW in the MATLAB simulation. It is recommended that the evaporation pressure should be allowed to rise up to 1000KPa for optimum performance since better cycle efficiency and net power output is achieved at higher evaporation pressure.