Chinese solar desalination plant could be salvation for Greek islands

Chinese scientists introduced a new system solar seawater desalinationwhich in the future may produce fresh water cheaper than bottled.

For now we are talking about a prototype, and not about a ready-made solution for cities and islands. But for Greece, where many islands suffer from drought, salinization of wells and a sharp summer increase in water consumptionsuch technology may prove particularly interesting.

The main thing is several points

• Chinese installation uses sunlightand not energy-intensive pressure, like reverse osmosis stations.
• Prototype area 0.75 m² gave about 20.16 liters of fresh water per day.
• The authors claim that the material absorbs up to 90.2% solar radiation.
• Economic evaluation promises water cheaper than bottled water only after long-term use, from approximately two years.
• For the Greek islands, technology could become additional source of waterbut not as a replacement for large desalination plants and networks.

Table of contents

• How the new desalination plant works
• What the prototype showed
• Why is this important for the Greek Islands
• Is it true that water will be cheaper than bottled water?
• What still remains a problem

How the new desalination plant works

The development was created by specialists Institute of Process Engineering, Chinese Academy of Sciences And Shenzhen University. The study was published in a scientific journal Advanced Materials.

The system is based on a three-dimensional photothermal material. It absorbs solar radiation, converts it into heat and accelerates the evaporation of seawater. The salts remain in the source water and the steam is then sent to a condenser where it is converted back into fresh water.

The authors used a structure of hollow multilayer nanoparticles connected by polymer chains. This design should prevent the material from sticking together and help it last longer in salt water.

According to the Chinese Academy of Sciences, the new material absorbs up to 90.2% sunlight, and the energy required to evaporate water is reduced by approximately 45.7%.

What the prototype showed

In laboratory tests, the material showed an evaporation rate of up to 38.14 kg of water per square meter per hour. This is a very high figure for photothermal systems, although it cannot be directly considered as a ready volume of drinking water.

Another result is more important: a demonstration installation with an area of 0.75 m² produced in natural sunlight 20.16 liters of fresh water per day.

This is not the volume for a large hotel or an entire island. But it is enough to provide basic drinking water to a small family, off-grid home, agriculture, fishing base or remote site.

The authors also used the resulting water to irrigate a small area. Spinach, corn and Chinese cabbage were grown on it. This shows that the technology could be useful not only for drinking water, but also for limited dryland agriculture.

Why is this important for the Greek Islands

For many Greek islands, water has already become not just a household issue, but one of the main problems of summer. Winters are becoming drier, heat increases evaporation, old networks lose water due to leaks, and the population of the islands increases several times during the tourist season.

On Naxos a large reservoir has almost dried up, and seawater has begun to seep into irrigation wells. On Karpathos authorities introduced restrictions on the filling of swimming pools. On Thassos the need for a new desalination plant was discussed. These cases became part of a wider water problem on the Greek islands.

On Santorini Water shortages are already affecting not only homes and hotels, but also agriculture. Drought and high temperatures reduce grape harvests, and in the summer residents, hotels, swimming pools and farmers compete for limited water supplies.

Therefore, compact solar desalination plants could become additional insurance for small towns, hotels, campsites, farms, beach facilities and remote island areas.

Such a system will not replace a large desalination plant in Santorini, Rhodes or Crete. But it could reduce dependence on water tankers, mainland water deliveries and overburdened networks, especially during peak heat waves.

Is it true that water will be cheaper than bottled water?

It is this thesis that sounds most loud, but it must be read carefully. Scientists do not claim that their installation is already selling water cheaper than bottles in the supermarket.

We are talking about a calculation model. According to the authors, if the equipment operates for at least two years, the cost of produced water may be lower than the cost of bottled water.

The comparison to bottled water is impressive, but the bottle involves more than just water purification. Its price includes plastic, packaging, delivery, warehouse, advertising and trade margin. Therefore, this does not mean that the new system is already cheaper than large reverse osmosis stations in terms of cost per cubic meter of water.

What still remains a problem

The new technology looks promising, but it is still far from widespread use. It is necessary to check how the material will work for years under the sun, salt, wind, dust and constant pollution.

Questions also remain about production cost photothermal materials themselves, capacitor repairs, replacement of parts and efficiency in winter or cloudy weather. The Aegean islands have plenty of sun, but there are strong winds, salty aerosols and seasonal changes in demand, and technology rarely enjoys all of these at the same time.

Main

The Chinese solar desalination plant remains an experimental technology, but its potential for Greece is clear. For islands where water becomes scarce even before the peak tourist season, compact plants could be part of a future drought protection system.

Not instead of large desalination plants, network repairs and restrictions on wasteful water use, but along with them. Because in conditions where there is a sea around and there is not enough drinking water, the idea of ​​getting it right on the spot with the help of the sun ceases to be beautiful scientific news and becomes a completely practical task.

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