Solar-powered desalination could unlock affordable freshwater and significant carbon savings.
Academics from the University of Texas examined how solar generation could supply part of the electric demand at the Kay Bailey Hutchison brackish groundwater, reverse-osmosis desalination plant in El Paso, Texas to inform the paper Solar desalination: Cases, synthesis, and challenges, published in Wires Water.
The Texas group also considered how solar could be used at a similar, hypothetical facility in Abilene in the same state and at proposed desalination plants in Abu Dhabi and the remote coastal town of Denmark, in Western Australia.
One of the chief obstacles to the deployment of solar-powered desalination is a lack of knowledge about the potential negative impacts of dumping large volumes of waste brine into the sea near such facilities.
Options to mitigate such impacts include ‘multiport diffusers’ which disperse the waste product at numerous outlets or using cooling water from thermal power plants to dilute the brain before disposal.
However, the paper’s authors added: “Potentially profitable commodities that can be extracted from brine include sodium, chlorine, potassium and magnesium.”
The researchers concluded solar was an interesting option to drive desalination, including when combined with energy storage and other renewable power sources, but noted a lack of financial modeling for the technology and of policy support for connecting such facilities to the grid.