Geothermal source potential for water desalination – Current status and future perspective

Direct use and power generation based on geothermal sources are growing at a steadfast pace around the world. Although available abundantly in many parts of the world, geothermal energy sources have been under-utilized in desalination applications. Geothermal sources have the potential to serve as excellent heat sources for thermal desalination processes. Since thermal desalination processes require large quantities of heat sources, geothermal based energy source represents a feasible, sustainable, and an environmentally friendly option. The advantage with geothermal source is that it can act as a heat source and a storage medium for process energy utilization. If these water sources have high dissolved solids, then they can serve as feed water for the desalination process. Since external energy consumption is minimized except for the mechanical energy requirements, geothermal enabled desalination processes could have less environmental impacts when compared to other nonrenewable energy driven desalination processes. Cogeneration schemes for simultaneous water and power production are also possible with geothermal sources as well as poly generation with multiple process benefits involving cooling and heating applications. This paper provides the present state-of-the-art of geothermal desalination with discussion on the benefits of geothermal desalination over other renewable and nonrenewable energy driven desalination configurations. Present status of the worldwide geothermal desalination and the potential for future developments in this technological area were discussed in detail with case studies for Australia, Caribbean Islands, Central America (Coasta Rica, El Salvador, Guatemala, Honduras, Nicaragua, and Panama), India, Israel, the Kingdom of Saudi Arabia, UAE, USA, and Sub-Saharan Africa.