Experimental Study of EP-OTEC Cycle

Abstract

Ocean Thermal Energy Conversion (OTEC) is a kind of renewable energy that generates electricity through driving the turbine by evaporating and condensing the working fluid with surface seawater of 26 ° C or more and deep seawater of 5 ° C or less. OTEC is well suited to take charge of the baseload because it can achieve a high operation rate in areas where high surface seawater temperature such as the equator is kept constant throughout the year. In operating OTEC, regionssuch as Korea where the surface seawater temperature fluctuates according to the season are not suitable for OTEC. However, the intake of deep seawater is easy with the seabed topography of the East Sea in Korea. So, it is under study to improve cycle efficiency using the unused energy such as power plant hot waste water, ship waste heat, geothermal heat as a heat source and deep seawater as a heat sink. Among them, EP-OTEC is a cycle that uses Ejector and Ejector Pump to increase the efficiency of OTEC system. The ejector is a simple device consisting of two inlet(motive and suction part) and one outlet(discharge part). When the high pressure fluid is introduced in the motive part, a low pressure is formed inthe suction part due to the kinetic energy from the motive fluid. The basic principle is that the two fluids introduced into motive part and suction part are mixed and discharged at medium pressure. In the EP-OTEC cycle using the ejector, t