Renewable-powered reverse osmosis desalination with active feedwater salinity control for maximum water production efficiency with variable energy input

A system for desalinating feedwater, including:

• at least one feedwater source;
• a reverse osmosis module;
• at least one input feedwater stream fed to the reverse osmosis module, wherein the input feedwater stream comprises water from at least one feedwater source, wherein said at least one input feedwater stream comprises a first feedwater stream and a second feedwater stream, wherein the second feedwater stream has a salinity higher than a salinity of the first feedwater stream;
• and
• a controller analyzing the level of energy available to the system, wherein the controller increases the salinity of the input feedwater stream proportional to an increase in available energy by increasing the proportion of the second feedwater stream in the at least one input feedwater stream.