This article delves into the exploration of a Brackish Water Reverse Osmosis (BWRO) desalination system, powered by a renewable microgrid that operates without the need for electro-chemical energy storage. The study takes a comprehensive approach, focusing on the Water-Energy nexus, with an emphasis on identifying operational constraints through an experimental BWRO prototype. The desalination system applies a "power-sharing" strategy alongside Power Field Oriented Control (PFOC) to ensure safe operation within pressurized systems. The integration of technological limitations establishes a "Safe Operation Window (SOW)" while accommodating fluctuations in renewable energy production. The ultimate objective is to optimize freshwater production capacity, considering the constraints of both microgrid electrical power and the BWRO unit. Real-time management of Water-Energy is facilitated by an Energy Management System (EMS), which maximizes water production and minimizes energy consumption under varying climatic conditions. In summary, this research offers valuable insights into sustainable water production through the utilization of renewable microgrids and innovative control strategies. The "power-sharing" approach, coupled with precise control of motor pump modes, significantly contributes to enhanced system efficiency. This study underscores the importance of addressing the Water-Energy nexus in the context of desalination for sustainable water supply.