08 Apr 2024 2 min read

How could desalination alleviate water scarcity?

By Elisa Piscopiello , Shichen Zhao

Turning abundant saltwater into usable fresh water is an obvious way of addressing water scarcity. In our new whitepaper we explore how technology could help alleviate the problem. 


Given that only 3% of water on earth is fresh, turning abundant saltwater into usable fresh water is an obvious way of addressing water scarcity. Desalination is becoming more attractive as it becomes more cost-competitive, technology scales up and fresh water supply dwindles.

Desalination processes can be mechanical (mechanical vapour compression and reverse osmosis), thermal (i.e. simple stills, multi-effect distillation, multi-stage flash evaporation, thermal vapour compression), or electrical (electrodialysis).

Reverse Osmosis (RO), a mechanical process that uses pressure, is the most used process and consumes less energy than the rest, as it is based on the use of semipermeable membranes that allow water molecules (smaller) to pass, but not salt molecules (bigger).

A deep dive into desalination components

Processes such as RO depend upon pipes and valves. Pipes are particularly important for desalination systems because they need to resist corrosion and leaching, which is where research into advanced solutions and specialist materials is focused on.


The seawater and brackish water desalination markets continue to grow. GWI expects capex to rise to $9.4 billion in 2027 from just under $6 billion in 2022, and opex to increase to $13.4 billion from $10.6 billion in 2022.

The above is an extract from our new whitepaper, Clean water technologies: overcoming the challenge of a drier world. Read the whitepaper to learn more about global water scarcity, and the cutting-edge technologies offering potential solutions.

Elisa Piscopiello

Senior ETF Analyst

Elisa joined LGIM as ETF Analyst in June 2021. She contributes towards the development and analysis of investment strategies, whilst also supporting ETF distribution and marketing efforts. Prior to that, Elisa worked as Multi Asset Investment Support Executive at Liontrust, and as Investment Dealing Assistant at Architas. In 2016 she graduated from the University of Kent with a First Class degree in Financial Economics with Econometrics. She holds the Diploma in Investment Management (ESG) and is a CFA charterholder.

Elisa Piscopiello

Shichen Zhao

Thematic Research Analyst

Shichen is a Thematic Research Analyst in the ETF team, contributing to growing the thematic equity ETF range from an investments, research and analytics perspective. Before joining LGIM in August 2023, Shichen worked as an Equity Research Analyst at Candriam, with a focus on global emerging markets and thematic investment research. She graduated from National University of Singapore with a MSc degree in Management in 2019.

Shichen Zhao