Exploitation of renewable energy sources for water desalination using biological tools

The emerging impacts of climate change and the growing world population are driving the demand for more food resources and creating an urgent need for new water resources. About 93% of Earth's surface is made up of water bodies, mainly oceans. Seawater attracted a lot of attention in order to be used as a sustainable source of usable water. However, an essential step in harnessing this source of water is desalination. Utilizing renewable sources of energy, biology offers several tools for removal of salts. This article for the first time reviews all currently available biological water desalination tools and compares their efficiency with industrial systems. Bacteria are employed as electrical power generators to provide the energy needed for desalination in microbial desalination cells. Its salt removal efficiency varied from 0.8 to 30 g/L/d. Many strains of algal cells can grow in high concentrations of salts, adsorb and accumulate it inside the cell, and therefore could be used without prior treatment for seawater desalination. This biological tool can yield salt removal efficiency of 0.4-5 g/L/d. Biopolymers are also used for treatment of seawater through enhancing water evaporation as a component of solar steam generators. Despite significant advances in biological water desalination, further modifications and improvements are still needed to make its use sustainable and cost-effective.

Automated summary

The impacts of climate change and population growth lead to a greater demand for food and new water resources. Seawater, which makes up 93% of Earth's surface, is being explored as a sustainable water source. This article reviews and compares various biological tools for water desalination and their efficiency compared to industrial systems. Bacteria in microbial desalination cells can generate the required energy for desalination, with salt removal efficiency ranging from 0.8 to 30 g/L/d. Algal cells can grow in high salt concentrations and be used for seawater desalination without prior treatment, achieving salt removal efficiency of 0.4-5 g/L/d. Biopolymers enhance water evaporation and are used in solar steam generators for seawater treatment. Despite progress, further improvements are needed for sustainable and cost-effective biological water desalination.