Integration of humidification-dehumidification desalination and concentrated photovoltaic-thermal collectors: Energy and exergy-costing

Water desalination by humidification-dehumidification-humidification (HDH) cycle is considered as a viable option for small-scale freshwater production in remote areas. When integrated with solar power generation units, this stand-alone co-generation system would become very attractive for reliable simultaneous freshwater and electrical power production. This study evaluates the performance of a co-generation unit based on integration of air-heated HDH desalination cycle with concentrated photovoltaic-thermal (CPVT) collectors. Mathematical model for integrated system under steady-state conditions has been presented. Exergy-costing method was applied to estimate the cost of system's products. The results show that the system would be able to produce 12 m(3) of freshwater and 960 kWh of electricity per year for a site having 1.88 MWh/yr solar irradiance. The unit cost for freshwater production and electrical power generation is estimated as 0.01 $/L and 0.289 $/kWh, respectively.