An ocean thermal gradient electric generating system is proposed for siting in hawaii. this system would operate a heat engine driven by heat flow from warm ocean water (cooled from 29 ⁰c to 25 ⁰c in the heating heat exchanger of the system), and cooled by heat flow to cold ocean water (which is heated from 3 ⁰c to 8 ⁰c in the cooling heat exchanger of the system). the ocean water used in the different parts of the heat engine is obtained from different depths of the surrounding sea. using this heat engine electricity can be produced at 90% of the corresponding carnot efficiency of the heat engine.