Electric power generation availability losses

Provided that the pressure difference between the two sides of the membrane is set to a value lower than the difference in their osmotic pressure, a water flux establishes across the membrane from the low- to the high-pressure side (i.e. from the low to the high salt concentration side). Therefore, the water flow rate on the high-pressure side of the membrane increases. The seawater stream diluted by pure water in the membrane module (brackish stream B1) is then sent to a hydrauhc turbine connected to the same shaft of the main pump. Since the turbine head equals the pump head (apart from the pressure losses along the circuit and the small head provided by the EPl pump) and the turbine flow rate is higher than the pump flow rate because of the water permeated across the membrane, a net mechanical power output is available at the shaft. A generator connected to the shaft finally converts mechanical to electric power. 

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