MADRID – In Spain, more than half of the population lives within 100 kilometres of the sea. One of the solutions to the drought and declining water reserves can be found in desalination plants. Therefore, why isn’t it used more?
Nearly 60% of the lagoons in not-so-wetland Doñana have dried up. In Fuerteventura, the drought is so severe that authorities are working with buckets to guarantee supplies. In the Axarquía region, irrigation associations are joining forces to limit the consequences of the drought as much as possible.
These are just a few headlines in the news of Saturday 8 April. The drought in Spain is severe. At the beginning of April, the water level in the Spanish reservoirs should be a lot higher than it is now. The entire reserve (reservoirs and underground water resources) in Spain is at 51% of capacity. Last year it was slightly lower at 47%. The average over the past ten years is 66%.
Furthermore, that will not change in the coming days. Some showers are not expected in the northwest of the country until Wednesday. And, after April, the rain is usually insubstantial.
Poor water management
Spain is not the only country facing a drought problem. In almost all of Europe, it is drier than it should be now. Italy and France have already taken emergency measures against the drought. In Spain, the drought is also exacerbated by poor water management. Environmental organisations such as WWF warn that this situation poses a greater risk in the coming years as the impact of the climate crisis intensifies.
Intensive and industrialised crops consume 80% of the water
Spain has experienced three periods of prolonged and intense drought in the last 40 years. Now a reduction in available water resources has been observed in many river basins. The country has nearly 4 million hectares of irrigated land. This includes intensive and industrialised crops that use 80% of the water.
In those areas where water is not available in rivers and reservoirs, groundwater is used. The WWF states that there are currently more than 80 aquifers in Spain where there is overexploitation.
This overexploitation of water resources and the climate crisis are the main causes of desertification in Spain. The Ministry of Ecological Transition estimates that 74% of Spain’s territory is susceptible to desertification. According to the same estimate, this crisis affects 20% of the European territory and 30% of the population.
The solution to this problem requires a change in water resources management. Management must be carried out in such a way that aquatic ecosystems and aquifers can recover. So that there are reserves again in periods of drought.
Desalination plants in Spain
With this available knowledge about the problem and the knowledge that such a large part of the Spanish population lives near the coast, one wonders why more desalination plants are not being built. In this sense, the sea is an almost inexhaustible resource that we can access even in the face of a very severe drought.
Spain is the first country in Europe (and the fifth in the world) with the largest capacity to generate desalinated water. That capacity is estimated at about five million cubic metres per day. An amount equivalent to the water consumption for 34 million inhabitants.
There are currently 68 marine desalination plants installed in Spain with a capacity of between 10,000 and 250,000 cubic metres per day. Despite these figures, there are areas, such as Murcia and Catalonia, where there is still a significant shortage and where desalination capacity needs to be expanded.
Desalination process is expensive and uses a lot of energy
With the desalination of water, drinking water for human consumption is obtained by separating salts from a brackish solution. The water can also be used for industry or agriculture. Desalination can therefore be seen as the solution to the water problem. Only there are still a few snags to the process.
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Despite the fact that more than half of the population lives within 100 kilometres of the sea, desalination has so far only been used in extreme circumstances. The process is much more expensive and requires much more energy than other methods of obtaining drinking water. Energy accounts for between 40 and 60% of the production costs of desalinated water.
Study in Cyprus
From a 2021 study on the environmental impact of Salting in Cyprus found that the country’s four desalination plants generate about 2% of their total greenhouse gas emissions. The plants also account for 5% of total electricity consumption in Cyprus, according to the study, one of the highest percentages in the electricity consumption sector.
In addition, the report notes that the desalinated water produced some 103 million cubic metres of high salinity and toxic saline effluents. Around the drainage pipelines, they affected the Mediterranean seagrass ecosystem in the region.
Renewable energy as a solution
Renewable energy can be used as a solution for relatively high energy consumption and greenhouse gas emissions. Desalination plants can operate on solar energy. The company Boreal Light in Berlin specialises in green energy solutions for water treatment plants. It has developed off-grid solar and wind desalination plants. These can therefore ensure greater energy independence and prevent major price fluctuations.
In this way, free water from the sea is available and free electricity from solar and wind energy. According to Boreal Light’s CEO, this means that it is possible to produce 1,000 litres of fresh water for only 50 cents. This would make the price of a cubic metre of desalinated water as competitive as direct access to fresh water from rivers or wells, he added. As technology improves, environmental and climate impacts will continue to decrease.
Reuse of water
Another key to ending the water problem in Spain is its reuse. Desalination and reuse of water are crucial to coping with the drought. Spain is the first country in Europe in terms of desalination and recycling. Regions such as Valencia and Murcia or the islands already have very high reuse rates of almost 80 to 90%. However, much remains to be done at the national level. No more than 10 to 12% of the already treated wastewater is reused. While reuse is many times cheaper than desalination.