There is an increasing demand for advancing conventional desalination technologies and developing novel solar powered desalination processes. In this chapter, the use of solar powered thermal desalination will be discussed comprehensively. The different existing methods of solar energy utilization for seawater desalination will be discussed, which includes solar stills, solar powered humidification-dehumidification (HDH) desalination, solar diffusion driven desalination, solar membrane distillation, concentrated solar power (CSP) based desalination, and solar pond distillation. The advantages and limitations of these thermal desalination technology will be discussed. In addition, the environmental impacts of solar desalination will be discussed due to its importance for adoption.
Part of the book: Desalination and Water Treatment
Solar energy has the potential to reduce the dependence on the dwindling supply of fossil fuels through concentrated solar power (CSP) technology. CSP plants utilize solar thermal energy to produce electrical energy based on different thermodynamic power cycles. Solar collectors, reflectors, receivers, thermal fluid, and turbines are the main components of each CSP plant and involve intensive heat transfer at all stages. This chapter illustrates the thermal characteristics of the main components used in CSP technology. In addition, the solar thermal fluid characteristics and its stable operational ranges are discussed in this chapter. Heat capacity, vapor pressure, volume expansion, density and viscosity of the thermal fluid should not differ significantly at different temperatures during various operation stages because these variations can cause failure in the system, which is designed at the fixed material properties. Currently, CSP technology is associated with a higher cost compared to the electricity generated through gas power plants. Many efforts are made to search for sustainable and inexpensive materials to minimize the cost of CSP. One critical issue faced by CSP technology is the intermittent nature of the sun. Modern CSP plants integrate thermal energy storage (TES) unit to smoothen the power production or to shift the production from peak sunshine hours to peak demand hours.
Part of the book: Heat and Mass Transfer