Effects of wind intermittence and fluctuation on reverse osmosis desalination process and solution strategies

With the significant increasing water demand and the fossil-fuel cost, the wind-powered desalination technique has become more and more attractive for coastal area. It has experienced fast development and brought amount of benefits into our daily life, industry and agriculture. The main risks for the further penetration of such autonomous and decentralized desalination systems are the intermittent and fluctuating nature of the wind power resource. They can potentially result in a series of problems, including negative effects on the membrane performance, the component service duration, and complexity of the plant configuration, operation and control. To avoid or alleviate these effects, the efforts about solution strategies have been developed and mainly divided into three categories. The first category is the energy storage trying to maintain a constant operation condition for the RO unit. The energy storage carriers include batteries, supercapacitors, hydrogen, flywheel, pumped water, compressed air, and their combinations. The second category is the hybrid energy system. In a hybrid energy system, wind energy combined with other forms of energy such as solar PV, diesel, gravitational potential energy is employed as the energy supply. The third category is adjusting operating conditions of RO process and matching the RO capacity with transient energy supply, to make the process be adaptable with the wind power variation. Based on above summaries and analyses, this paper is aiming to be helpful for the design, operation and application of wind powered RO hereafter.