Desalination: The Critical Global Technology That Needs Nuclear Power

In this picture taken on March 30, 2023, Mohamed Ali al-Qahtani, Phase General Manager at the Ras al-Khair water desalination plant, owned by the Saudi government's Saline Water Conversion Corporation, inspects desalinated drinking water from a tap at the facility in Ras al-Khair along the Gulf coast in eastern Saudi Arabia. (Photo by Fayez Nureldine / AFP) (Photo by FAYEZ NURELDINE/AFP via Getty Images)

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Water covers more than 70% of the Earth's surface yet risks of scarcity and limited access form one of the defining crises of the coming century. Only 2.5% of Earth's water is fresh, and the majority of that is locked in glaciers or deep aquifers beyond easy reach.

Climate change together with urbanization and development of coastal areas, expansion of agriculture and industrialization have created conditions whereby governments worldwide face not just water challenges but crises of real severity. Global water consumption by humans has grown no less than 25% in only the last two decades, even as increased temperatures in many areas has reduced annual availability of freshwater.

The intense June 2026 heatwave centered on Europe proves that this is not limited to semi-arid or arid parts of the planet. Water demand in this temperature region reached a critical peak in nations like the UK and France, outpacing regional water supplies and straining infrastructure, thus forcing the use of emergency restrictions.

In truth, the crisis is about not water per se but clean water. Access to safe drinking water defines one of the most basic determinants of global health. An important report by the World Bank, released in late 2025, details the disturbing decline in freshwater and clean water reserves paired with rising demand, leading to what it calls the phenomenon of “mega-drying regions.” It lays out three essential areas that policy must address: how to better manage demand, improve water allocation, and increase water supply itself.

To fulfill this last requirement, perhaps the most basic of all, the WB endorses what many nations have already decided: a return to the sea.

A Booming Industry at a Critical Crossroads

Desalination — the removal of salt and other minerals from non-potable water — is no longer a niche technology for desert states. It has grown into a global industry whose market value in 2025 was $24–28 billion. Growing at a compound annual rate of 9%-12%, this is projected to reach as high as $65 billion by the early 2030s. At present, there are more than 20,000 desalination plants operating in at least 150 countries. As such, the process has matured in the era of climate warming from an alternative solution to an essential pillar of water security.

Global population, meanwhile, is projected to reach 9.7 billion by 2050, adding more than 2 billion people to a planetary surface where freshwater scarcity is already widespread. Consider, for example, the commonly used threshold (Falkenmark Indicator) for water scarcity in a specific area is 1,700 m³ per person per year: large stretches of North and East Africa, the Middle East, South Asia, and northern China were at less than half this figure two decades ago.

Seawater (SW) is the main feedstock for desalination, though this depends on geography. In the Persian Gulf, where levels of naturally available freshwater are <100 m³, there are 3,400 desalination plants in operation along the coasts. The Middle East and Africa currently dominate the industry, in fact,accounting for more than half of global market share. The Gulf states have relied on desalination for decades, and the scale of new investment is staggering: Saudi Arabia's desalination capacity was expected to rise from 5.6 million cubic meters per day in 2022 to 8.5 million by 2025.

The Oceans Are Not The Only Resource Option

Besides the oceans, there exists a great worldwide volume of brackish groundwater in subsurface aquifers, either sediments or porous rock layers. This category is typically defined as water with 1,000–20,000 parts-per-million of total dissolved solids, with actual exploited resources usually under 10,000 mg/L. This is much less saline than seawater at 35,000 ppm.

Globally, seawater is used for about 59% of desalination, while BGW makes up 22%, the rest being mainly rivers, lakes, and wastewater. There is a technical advantage to using BGW: where seawater yields around 50% of its volume as freshwater, brackish water yields 70%-90%. Lower salinity (dissolved solids) means lower energy consumption and higher recovery rates.

In the US, desalination of BGW began in Coalinga, California in 1965. Today there are more than 300 plants, mainly in the West, Midwest, and Florida meeting municipal water needs. According to the U.S. Geological Survey, total brackish groundwater resources in the U.S. at depths up to 3,000 ft are no less than 800 times the total fresh groundwater pumped from all other sources every year.

Even so, current output is a small fraction of the larger potential. Given the reality of growing water supply problems, particularly (but not exclusively) in the West, the exploitation of this resource has drawn increased attention. This is a trend that is not likely to stop, given the increased occurrence and intensity of drought in areas far removed from any coast.

Desalination Technologies – Trading Energy for Water

Desalination is an energy-hungry process. There are two chief technologies in dominant use, and both require significant amounts of power.

For seawater, the process of reverse osmosis (RO) is used, employing high-pressure pumps to force the high salinity water through very fine membranes that capture salts and contaminants. This is the reverse of normal osmosis, which involves the opposite—water naturally flowing from a more dilute container to one of higher concentration.

RO has overtaken older, thermal methods in which saline water was heated to evaporation, with vapor collected as freshwater, leaving salts and other minerals behind. RO is much more efficient, requiring 2.5-4 kilowatt-hours per cubic meter of water produced, compared to 5-15 kWh/m³ for thermal processes.

For brackish water, the technology is electrodialysis (ED), which uses an electric field and ion-selective membranes to draw salt ions out, leaving the water molecules intact. This process has higher recovery rates (final freshwater) and is more efficient at lower salt concentrations than RO, since it doesn’t utilize high-pressure pumps. Costs rise rapidly with salinity, however, and greatly exceed those of RO for seawater.

Because electricity makes up 40%-50% of the total operating cost, research has been focused on improving energy efficiency. Enough success has been achieved in recent decades that one expert has noted “the electricity required to supply a family of four with desalinated water for a year is equivalent to running a refrigerator.” Further advances are sought in membrane efficiency, AI-based applications, hybrid systems using both RO and ED, and power supply.

Decarbonization defines another major frontier. The switch to newer technology has reduced costs overall, yet it hasn’t displaced the use of carbon sources. Only about 1% of global desalination capacity is powered by noncarbon energy. In the Middle East, roughly 93% runs on natural gas and 6% on oil, while in parts of Asia coal is the power source. If carbon sources will be used well into the future, natural gas is the best choice. But if decarbonization defines the goal, other choices will need to be made.

In global terms, desalination seems, for the time being, carbon-locked. While plans exist to increase the use of renewables, the focus on solar and wind comes with problems. RO and ED require uninterrupted power and voltage stability. Though battery storage and helps, it adds cost and complexity and does not always cover the gap, so natural gas backup is needed. A different energy technology able to operate continuously over a long lifespan and needing far less land is drawing renewed attention.

Nuclear Power - Superior Choice to Power Desalination

The case for nuclear-powered desalination is, at its core, a case for reliability, stability, and longevity. Nuclear generates electricity continuously, regardless of weather, and offers uniform advantages across geographie and climates with a lifespan up to 80 years or more. This compares with 25-30 years for solar and wind and 10-15 years for utility-scale battery storage.

Nuclear desalination is not a theoretical concept. India has operated small nuclear-powered desalination demonstrations since the early 2000s. Russia, South Korea, and China have long-standing programs. The US Navy aircraft carriers reportedly use their nuclear-generated electricity to desalinate 1500 m³/d each for use onboard.

What has changed in recent years is the arrival of small modular reactors (SMRs): factory-built, scalable reactors with generating capacity between 50 and 300 megawatts, small enough to co-locate with a desalination facility.

SMRs could offer superior economic feasibility for decarbonizing desalination over decades as opposed to multigenerational replacement of solar/wind/battery storage. A co-located SMR can also provide process heat for thermal desalination steps, increasing overall system efficiency.

No SMR-desalination pairing is yet operating at commercial scale. But national-level planning is advancing steadily. The question is no longer whether nuclear will play a role in the future of desalination, but how quickly that future arrives.

Environmental Issues: Brine Waste as Challenge and Resource

Desalination plants create two liquid products: freshwater and brine. The latter is a highly concentrated saline waste stream that carries about twice the salt concentration of seawater. Global brine production in 2025 exceeded 140 million m³, which translates to more than 50 billion m³ per year—the total volume of Lake Erie in the U.S.

Brine is most often discharged to the ocean and can damage marine ecosystems if mitigation methods are lacking. Such engineering exists in the form of diffuser technology that disperses brine as it is discharged, rapidly diluting it. Multiport diffusers combined with site-specific management of intake and outflow has been proven to minimize impacts.

Where such technology has not been used, as in some portions of the Persian Gulf, discharges have reduced fish populations and led to coral mortality.

On the other hand, brine can be valorized as a potential resource of critical minerals. Because it doubles the dissolved solids already present in seawater, it offers real possibilities for the extraction of metals that include lithium, magnesium, boron, and potassium, as well as a range of critical metals present in smaller amounts, such as gallium, scandium, vanadium, and indium.

Demonstrated in the lab and in pilot projects for certain minerals (magnesium), brine mining defines a frontier for innovation. While it is likely an exaggeration to say this could soon turn “waste into wealth,” it represents one component in a larger domain of research into extracting such metals from a variety of fluid sources: geothermal brines, mine tailings ponds, waters produced in oil and gas wells, and subsurface brines in deep rock layers.

Toward a New Water Economy

The global desalination industry stands at an inflection point that will shape the lives of billions of people over the next several decades. The freshwater shortfalls ahead are not speculative — they are the result of arithmetic: more people, hotter temperatures, deeper droughts, aquifer depletion. In the meantime, unclean water remains the source of disease and child mortality in most of the world’s continents. Desalination is one of the few technologies capable of producing clean water at the scale those shortfalls will demand, independent of rainfall or river flow.

Nuclear must be counted among the most promising long-term foundations for a truly sustainable, decarbonized sector of desalination. Moreover, given the critical importance of water, commercialization may well be aided or deferred by direct government support in many cases.

Nuclear is not a panacea. As the World Bank emphasizes, new energy options need to be paired with better, more conservation-oriented water management. At present, the technologies that comprise desalination yield less than 1% of humanity’s total water use each year. This figure, which may need to double by mid-century, should be paired with the fact that over 70% of this total for homo sapiens goes to agriculture—food. Such highlights the reality that nuclear, together with other noncarbon sources, will prove essential to our future in more than one way.