Spanish desalination know-how, a worldwide benchmark
For years humans have looked to the vast bodies of saltwater hoping they could provide enough drinking water for the global population and meet the needs of other uses such as industrial or agricultural uses, but the economic and environmental costs of desalination have been the biggest obstacle to what could be the solution to the global water crisis. John F. Kennedy, president of the United States between 1961 and 1963, believed that obtaining drinking water from salt water inexpensively would be in the long-term interest of humankind, eclipsing any other scientific achievement: "I am hopeful that we will intensify our efforts in this area," he said. And as if he were a visionary, starting in the 1970s, desalination gained momentum to become a necessary complement to solve the water crisis in which we have been immersed for years.
The economic and environmental costs of desalination have been the biggest obstacle to what could be the solution to the global water crisis
The Earth is known as the blue planet because three quarters of it are covered by water, but most of it is salt water and, out of the fresh water, very little of it is suitable for human consumption. A priori this is a problem, given the increase in water demands and a climate crisis that further exacerbates the pressures on water resources worldwide. However, thanks to technological advances, we can resort to the non-conventional water resources – water reuse and desalination – as an option to meet these demands.
Thanks to technological advances, we can resort to the non-conventional water resources such as water reuse and desalination
According to the International Desalination Association (IDA), there are currently some 18,000 desalination plants worldwide with an operating capacity of almost 80 million cubic meters of water per day (m³/day). In terms of location, the Spanish Institute of Foreign Trade (ICEX) says they concentrate for the most part in the Middle East, where countries such as Saudi Arabia, the United Arab Emirates, Israel, Kuwait and Qatar account for a third of the world's facilities. "The Arab, Mediterranean and North African countries concentrate not only the largest desalination plants in the world, but also the largest desalination projects," says Araceli Iniesta Alonso-Sañudo, head of the water sector at ICEX.
The United States also stands out, with 10% of the total, and Spain with 5.7% and more than half of the desalination plants in Europe, in fourth place in terms of installed capacity. Furthermore, according to the Inter-American Development Bank (IDB), in recent years Latin America and the Caribbean (LAC) has become one of the largest emerging desalination markets. However, "all these plants only satisfy between 1 and 3% of the world's drinking water needs," says Araceli Iniesta, which leaves "an extraordinary margin for growth" in this field.
In any case, desalination is presented as a real, viable and safe alternative to water supply problems, especially in those areas suffering from water shortages, where Spanish engineering has played a fundamental role.
A long history of desalination
Spain, a pioneer in the process of water desalination – the first desalination plant in Europe was installed in Lanzarote in 1964 – has more than fifty years of experience in this area, which has made it one of the world leaders, both in terms of installed capacity – fifth in the world – and the strength of its industry, with design, construction and operation companies, consultants, suppliers and research centres. Through the AGUA Program (Actions for Water Management and Use) promoted by the government in 2004, Spain adopted a new water policy approach more in line with the Water Framework Directive (Directive 2000/60/EC) where water desalination was a key pillar. It was a clear commitment to desalination as an essential strategy to solve the problems arising from the water resources deficit on the Spanish Mediterranean coast and, in addition, a great opportunity for Spanish companies to build large desalination plants both inside and outside the country.
According to the Spanish Association of Desalination and Reuse (AEDyR), Spain currently produces around 5,000,000 m³/day of desalinated water, used for human consumption, irrigation and industrial purposes. There are a total of 765 desalination plants in the country, of which 360 are seawater desalination plants and 405 are brackish water desalination plants. In terms of their production, 99 are large capacity, i.e., they have a production of between 10,000 and 250,000 m³/day, 450 are medium capacity (between 500 and 10,000 m³/day) and 216 are small capacity (between 100 and 500 m³/day of production).
"At present, the drinking water demands on the Mediterranean coast and the islands are met," says Domingo Zarzo Martínez, director of Innovation and Strategic Projects at Sacyr Agua and president of AEDyR. In fact, drinking water on the islands of Lanzarote and Fuerteventura comes entirely from desalination; however, "there are sectors such as agriculture that will need an increase in installed capacity to meet their demand, although it is a more expensive resource than conventional ones," he says.
Thus, although it is true that the country has not built any large desalination facilities for quite some time, the focus has been precisely on meeting the needs of more specific uses with smaller capacity plants, especially for agriculture, which, the same as it occurs in Chile with the mining sector, is a safe bet.
However, if we talk about desalination at a global level, we must bear in mind that the maturity of the sector has made Spanish companies leaders in this area, carrying out projects everywhere the world and in very diverse and demanding conditions.
A clear example of this is ACCIONA, the undisputed leader in desalination in the Middle East, with the construction of six desalination plants in Saudi Arabia, three of which have already been completed (Al Khobar-1 and Al Khobar-2 and Shuqaiq 3), in addition to two desalination plants in the United Arab Emirates (Fujairah and Jebel-Ali) and in Qatar (Umm Al Houl 1 and 2 and Ras Abu-Fontas), another desalination plant in Hong Kong (Tseun Kwan O) and the Los Cabos desalination plant project in Mexico. "ACCIONA is already desalinating more than 5.5 million m3/day with more than 85 plants built around the world and providing drinking water to more than 28 million people", says Pedro Miranda, head of International Desalination.
Leaders in reverse osmosis desalination
ACCIONA specializes in the development and application of reverse osmosis technology to water desalination and thus address water scarcity challenges. They cover the entire life cycle of the project: design, construction, commissioning, operation and maintenance of the seawater or brackish water treatment plant.
On the other hand, since the 1980s GS Inima has been actively operating in the desalination sector. Diego Vera, Business Development Director, explains that the company has more than thirty desalination plants with a capacity of more than 10,000 m3/day and a total installed capacity of more than 1.5 million m3/day, supplying water a total population of more than seven million population equivalents. Among its most important projects are the desalination plant in Atacama (Chile), commissioned in March 2021, the desalination plant in Ensenada (Mexico), Barka V and Ghubrah III in Oman, both under a BOO (build, own, operate) model, and Daesan, the first large-capacity plant in South Korea, awarded in 2021.
"GS Inima is a world leader in the reverse osmosis desalination market"
Marta Verde, CEO of GS Inima, tells us in this interview the keys to the success of the company, one of the most important players on the Spanish hydric scene.
Tedagua provides two portable desalination plants to produce water for irrigation purposes on the Canary Island of La Palma
This pool of Spanish companies leading the desalination market also includes Tedagua, which has more than twenty years of experience in the design, construction, operation and maintenance of all types of conventional plants, from desalination plants built for hotel complexes or small farms in the Canary Islands, such as the Salto de Chira desalination plant, the large seawater desalination plants such as Escombreras in Spain with a capacity of 63,000 m3/day, or those of Provisur in Peru, Tuas III in Singapore, Beni-Saf in Algeria, Spence in Chile or Magtaa, the largest desalination plant in Africa. "In total, Tedagua has designed and built more than 100 desalination plants, which add up to a total of more than 1,500,000 m3/day of desalination capacity," adds Álvaro Diaz del Rio, head of the Innovation Department.
Another Spanish company with a strong presence in the desalination arena is Almar Water Solutions, whose team has extensive experience in this sector. In addition to its most emblematic project, the Shuqiaiq 3 desalination plant, awarded to a consortium formed by Almar Water Solutions, ACCIONA, Marubeni Corporation and Rawafid Alhadarah Holding Co, it has smaller plants in Latin America and North Africa with a production ranging from 75 m3/day to 35,000 m3/day that are just as important, as they produce water to carry out the production processes of many companies and their activities, which otherwise would not be possible. "We have not been a company for many years, but we have been working and winning projects at a very good pace. We hope to expand these figures in the near future," says Arantxa Mencía, Global Business Development Manager.
The water-energy nexus in desalination
Desalination involves removing salt from seawater and filtering it to produce quality water, a solution that is not without its challenges. Throughout the history of its implementation, the major limiting factor has been that it requires large amounts of energy, which in turn raises the cost of producing water.
Its major detractors have always pointed to the cost of production, the high energy consumption and the environmental impact generated. However, the technical, economic and scientific efforts made by the Spanish sector have shown that it is a viable and sustainable alternative for a multitude of water uses. In this regard, Spanish companies have contributed all their know-how in order to make desalination increasingly efficient and cost-effective.
Almar Water Solutions offers both the technical capacity and the financial tools to promote the development of desalination plants around the world: "Making projects more sustainable and saving on costs are two key points for the industry", says Arantxa Mencía. "The energy cost of desalination plants has been the most critical issue in these projects, and great progress has already been achieved in this area".
Meanwhile, ACCIONA, a global leader in water solutions, not only promotes digitalisation through the use of digital twins, augmented reality, artificial intelligence, IoT or machine learning, but they have also made reverse osmosis technology – the most widespread technology, representing about 71% of the technology worldwide and with 6.5 times less greenhouse gases emissions than thermal desalination processes – their flagship: "Reverse osmosis technology has evolved in such a way that we have achieved minimum costs in an efficient and sustainable manner," comments Pedro Miranda. This technology is combined with pre-treatment processes such as ultrafiltration – widely used – to obtain high water quality, eliminating all suspended solids, bacteria and viruses, and thus contributing to improving the performance of the reverse osmosis membranes.
In recent years the development of new technologies for desalination using membranes has thrived. DuPont Water Solutions, an American company with a significant presence in Spain, has extensive experience in this area, with more than one million membranes installed worldwide. They include the Torrevieja plant with more than 25,000 membranes and the Águilas plant with more than 20,000 membranes in Spain, which have been in operation for more than seven years with no need for replacement; the Khor Fakkan plant in the United Arab Emirates, with more than 1,700 membranes (operating for eight years with no need for replacement); and the Perth and Southern Seawater Desalination Plants in Australia, with more than 18,000 membranes each, which have been operating for more than ten and nine years respectively, with no membrane replacements.
"At DuPont, we have decided to make a strong commitment to product quality. This way, we are able to offer great product durability and thus extend the useful life of the membranes, helping our clients reduce total operating costs", says Guillem Gilabert Oriol, Desalination Technical Leader of the company. Among all the membrane technologies available, the DRY membranes (dry tested) for seawater and the FilmTec™ Seamaxx™ membranes, which allow seawater desalination while achieving maximum energy savings, stand out for their innovation. Similarly, DuPont™ B-Free™ technology – possibly the most innovative technology on the market today – is an innovative pretreatment that sits between ultrafiltration and reverse osmosis and has been successfully tested at Elmasa's Masplomas I desalination plant in the Canary Islands: "It manages to protect the reverse osmosis membranes from biofouling, practically eliminating chemical cleanings in reverse osmosis, and thus increasing the useful life of the membranes, as well as reducing the plant’s down time and increasing its productivity."
In addition to all these technologies, there are also other ones, less widespread and advanced, such as distillation or electrodialysis. At Tedagua, for example, they are committed to the search for disruptive technologies based on electrical potential difference for ion removal, such as electrodeionization or capacitive deionization: "The main challenge is to find materials with suitable physical-chemical characteristics for the manufacture of electrodes that optimize the processes of adsorption and desorption of salts", explains the head of the Innovation Department.
Synergies between water and energy are one of the key factors in the progress of desalination
Synergies between water and energy are one of the key factors in the progress of desalination. The Swiss company ABB, which also has a presence in Spain, is a technology leader that promotes the digital transformation of the industry and will power the world's largest seawater desalination project in Abu Dhabi. The company specializes in variable speed drives for the water industry; its technology achieves energy savings of between 20% and 60% in desalination plants, as well as a considerable reduction in maintenance costs.
In addition to this line of research, in early 2020 Aqualia acquired 51% of HAAISCO (Haji Abdullah Alireza Integrated Services Ltd.) from the Saudi Arabian group Haji Abdullah Alireza, which is responsible for the operation and maintenance of several desalination plants in Arabia. They include the King Abdulaziz International Airport plant in Jeddah, the KAUST University reverse osmosis seawater desalination plant in Thuwal, the MED (multi-effect distillation) desalination plant in Rabigh, and the operation and maintenance of the desalination plant and drinking water distribution system in the industrial area of Jizan (Jizan City for Primary and Downstream Industries – JCPDI) in the southwest of Arabia, bringing the total number of facilities managed by the company worldwide to 26.
In fact, as Domingo Zarzo of AEDyR explains, energy consumption has been greatly reduced in recent years: "Compared to the more than 20 Kwh/m3 of the first desalination plants in Spain (by evaporation technology) in the 1970s, consumption has been reduced to current values of less than 2.5-3 Kwh/m3" or, in slightly more understandable values, "the energy consumption associated with the production of desalinated water that a family of four would need to meet their drinking water needs for a year, is less than the energy consumption of their refrigerator during that year".
An accessible future
While it is true that the price of energy has a significant impact on the price of desalinated water – it can represent between 40 and 60% of production costs – "it is very difficult to reduce the energy consumption of desalination plants even more", says the president of AEDyR. Thus, with the decrease in the price per cubic meter of water produced, which has practically reached its lower limit, the future challenges lie in replacing the use of fossil fuels with renewable energies and reducing the impact of the brine produced in the process, which pollutes coastal ecosystems: "What we have to work on is the implementation of renewable energies and self-consumption to reduce dependence on external energy sources". In this regard the sector is doing well: "Many of the water plants being planned today include an alternative energy source, such as solar and/or wind", says Diego de Vera, from GS Inima. "Renewable energies together with desalination processes are another point to highlight, since they solve one of the usual problems in desalination, which is to obtain a continuous and cost-effective power supply to make the desalination process viable", says Arantxa Mencía from Almar Water Solutions.
Future challenges include replacing the use of fossil fuels with renewable energies and reducing the impact of brine.
Globally, desalination is positioning itself as an unavoidable necessity: "The outlook is frankly positive for the sector, although we must be very aware of the challenges we are facing: energy efficiency and environmental impact," emphasizes Raúl Fernández, head of Tedagua's Engineering Department. "We are getting closer and closer to the theoretical thermodynamic limit of desalination, and it is for this reason that it is more evident than ever that we must innovate beyond product specifications," says Guillem Gilabert.
As for the outlook, Araceli Iniesta, from ICEX, points to increased concerns about planning, trying to reduce water consumption and searching for alternative sources, the digital transformation, rationalization of energy use, and reducing environmental impacts as key issues for the global water sector in the coming years, in a context of high competitiveness for companies. "The margin for growth for desalination worldwide is large and Spanish companies are well positioned in the sector, with many of them occupying very prominent places in the ranking of large international companies."