Chen C, Jiang Y, Ye Z, Yang Y, Hou L (2019) Sustainably integrating desalination with solar power to overcome future freshwater scarcity in China. Global Energy Interconnection. 2(2): 98-113

Freshwater resources and energy are the two material foundations of human survival and the two challenges for human sustainable development. China’s huge population needs a large amount of freshwater for basic necessities. Desalination is an intelligent and promising technology for increasing water resources to realize a sustainable supply of freshwater. However, high levels of energy consumption and greenhouse gas emissions have restricted the development of desalination. Solar energy has the unique advantage that it can be harnessed in different forms. This paper discusses the water resources and solar energy utilization status in China and presents a comprehensive review on a possible solution: coupling desalination technologies with sustainable energy. China’s desalination market is reviewed, and the energy consumption for several desalination processes is summarized to present a brief outlook of desalination techniques in China. Potential coupled methods for solar-powered desalination are compared. This study will facilitate understanding of the latent water crisis in China and help China’s desalination market transition from conventional energy sources to choose an appropriate solar-powered desalination process.

Desalination, Solar energy.

Fig.1 Total water resources (100 million m³) based on cartographic data from the National Bureau of Statistics

Fig.2 Water resources per capita (cubic meters) based on cartographic data from the National Bureau of Statistics

Fig.3 Seawater desalination distribution in China (2017)

Fig.4 Annual sunshine hours in China (2016)

Source: National Meteorological Information Center

Fig.5 Schematic of solar power coupled with desalination

Fig.6 Schematic diagram of a desalination system integrated with a solar chimney

Fig.7 Schematics of solar stills: (a) single stage solar still,(b) solar still with collector, (c) solar still with condenser, and(d) multi-stage solar still

Fig.8 Worldwide desalination technologies powered by indirect solar energy (left) and desalination technologies used in China (right)

Fig. 9 Schematic diagram of solar-MED components for desalination and power generation: solar field, boiler heat exchanger, pump, turbine, recuperator, and MED

Fig.10 Operating principle of the solar-powered reverse osmosis (RO) system