The air is dry, bringing little humidity to any rugged plants clinging to life.
But here, somehow, are cucumbers: rows and rows of them. No, this is not a mirage brought on by the unforgiving heat of the Jordanian summer; this is the Sahara Forest Project’s (SFP) first working facility, using engineering ingenuity to bring food, energy and water to formerly arid land.
Cucumbers grow in one of the greenhouses (Credit: Max Fordham/ Sahara Forest Project)
According to the United Nations, Jordan is one of the four driest countries in the world. There are only 147m³ of water per person per year, and estimates predict a drop to 90m³ by 2025.
Yet, last month, there were water-filled greenhouses with humid, cooled air and nurtured plump vegetables as Jordan’s King Abdullah II and Norway’s Crown Prince Haakon officially opened the SFP’s “launch station” outside the port city of Aqaba. Investors behind the project, including the European Union and the Norwegian government, hope the small facility will produce up to 130 tonnes of organic vegetables per year on just seven acres of land previously deemed unusable. The facility is set to grow to 490 acres, and backers hope it could be a shining model of sustainable agriculture as the global temperature rises and deserts swallow land.
In a region fraught with international tensions, food security is also a pressing concern. In Yemen, civilians have starved during a Saudi blockade and in Qatar, the site of the SFP’s first tests, people hurriedly stockpiled food after Gulf neighbours – which provide 80% of the country’s food – cut diplomatic ties and halted trade.
Companies behind SFP, including British firm Max Fordham, hope to show how engineering innovation can grow food in even the harshest of environments. “Relying heavily on food imports is a risky position to be in,” says senior partner Tom Bentham. “I think it’s completely reasonable to make your land more productive.”
Sun, sand and sea
After the project began in 2008, Max Fordham environmental engineers noted two things Jordan has plenty of: “You have got abundant sun and in some areas you have access to saltwater as well,” says Bentham. “To use those resources to make the desert areas more productive, we liked that idea, and we weren’t put off by the fact that it seemed counter-intuitive.”
The firm carried out thermal analysis, working out how much the air could be cooled for vegetables to grow in greenhouses. The technique selected to cope with the high temperatures and low humidity was running the dry air over “pads” of seawater.
As the air travels over the water it collects moisture and cools by as much as 15°C, creating a suitable environment for the plants. The water also collects inside the roof overnight, providing freshwater for the crops (after the hardy and easy-growing cucumbers, SFP hopes to grow all types of vegetables).
When fully operational, a solar energy tower will power the facility. If its turbine ever generates more energy than needed, the electricity could be exported – or, more usefully, it could desalinate more water for the crops.
It is all relatively simple engineering, but combined in a sustainable and environmentally-friendly way. “It is a synergistic principle, where outputs of one technology are the inputs of others, and vice versa, to maximise the effectiveness of all of it,” says Joel Gustafsson from Max Fordham. “That’s the idea and it largely works.”
Read enough publicity for large-scale projects and after a while you might notice a recurring phrase: “a holistic approach”. Here, it seems completely justified and the proposals for interconnected operations are almost dizzying: excess saltwater cooling the solar turbine, increasing its efficiency; external plants flourishing thanks to the moisture, in turn reducing dust and stabilising the ground; waste heat from the solar facility evaporating more seawater and providing freshwater. In areas below sea level, operators will even need less energy to pump water to their stations.
Innovative application of technology
The project is not the first time crops have grown in the desert, but it may be the most sustainable. Saudi Arabia is suffering from a water shortage after exhausting its underground aquifers for agriculture, but the SFP’s reliance on seawater and sunlight makes it much more reliable than fossil-fuel energy and so-called “fossil water”.
With large 50MW solar plants, the group claims facilities could produce 34,000 tonnes of vegetables per year and sustain more than 800 jobs, all while exporting excess energy and absorbing carbon dioxide.
“The Sahara Forest Project demonstrates that innovative application of technology has the potential to revolutionise our land-use systems in a way that benefits the climate, people and business,” said Vidar Helgesen, Norwegian minister of climate and environment, at the opening. “I, for one, am extremely excited to see how this project develops and how it can inspire other similar initiatives.”
With the potential for further increases in the global average temperature to cause environmental havoc, and further spread of deserts thanks to human activity, the facility in Aqaba could show a way forward.
For the world to meet climate targets, decarbonisation must happen now, says Jenifer Baxter, head of energy and environment at the IMechE. “You have to look for technologies that we know do the job, and do it quickly,” she says. “That is what we want to see countries doing and that is what they are doing here. We need to get emissions down as fast as possible.”
Content published by Professional Engineering does not necessarily reflect the views of the Institution of Mechanical Engineers.