This study of Reverse Osmosis plant operation shows the energy efficiency of Energy Recovery Inc. (ERI) is around 98.57 %, while the energy efficiency of Turbo pumps is around 82.5 % Recovered from the rejected water pressure. In-stream-2, which has Energy Recovery Inc. (ERI), is installed; feed 60% water through Energy Recovery Inc. with Pressure Exchanger Booster pump, and maintains 40% of total feed water through the High-Pressure pump. Total power consumption in the High-Pressure Pump Motor and Pressure exchanger Booster pump motor is 6,535,824.82 KWH/Annum. It saves more energy as compared to stream-1, which has a Turbopump installed for Energy recovery. In-stream-1, total feed water is passed through a high-pressure pump with a discharge pressure of 40 kg/cm2 and then fed into the Turbopump. The Turbopump boost feed water pressure up to 60 kg/cm2. Total power consumption in a High-Pressure Pump Motor is 10,046,065.14 KWH/Annum. A 3,510,229.14 KWH power cost has been saved per annum in a 12.6 MLD Sea Water Reverse Osmosis-based Desalination plant. Regarding the financial aspect, a cost saving of 10,881,710.33 INR per annum has been saved using Energy Recovery Inc. (ERI) over Turbo pumps.