Putting solar panels in the Saudi Arabian desert sounds like an obvious thing to do. There’s cheap real estate, ample sunshine and the possibility of one of the biggest oil-producing countries transforming itself into one of the biggest producers of solar-energy.
It is something that cannot happen quickly enough. Around a third of the oil pumped in Saudi is used to generate electricity for the country, while demand for power is growing at around 8% a year, the fastest in the region. If these rates continue, some estimates suggest the oil capital of the world may one day become a net importer of oil to power itself. Yes, you read that right- the country with one of the world’s largest oil reserves could actually have to import oil.
As a result, the country plans to invest a staggering $109bn over the next 20 years into solar, with the intention of generating more than 30% of their electricity from the sun - up from practically zero today. It is all part of the government’s plan to break the country’s oil dependency and give it a long term future after the oil reserves eventually run dry.
But if all of this sounds too good to be true, you’d be right. Saudi Arabia’s plans have a dirty secret.
In just one hour, a desert sandstorm can plaster even the toughest solar panels with a thick layer of residue, reducing their efficiency by upwards of 70-80%. If the panels aren’t cleaned almost daily, they become virtually useless.
Most solar installations around the world, large or small, use automated water cleaning devices, or manual labor with hoses to wash them down. But Saudi Arabia is in one of the driest regions on earth. Around 90% of its water supply comes from desalination – converting saltwater to freshwater. It is a very expensive and energy intensive process. Using this precious resource to clean vast arrays of solar panels in the desert would be a waste of the energy they produce, as well as making the economic model more difficult to justify.
So, while there is tremendous potential for harnessing solar energy from desert environments, it has been relatively impractical on a large scale. But that may soon change.
Enter Nomadd, or “no-water mechanical automated dusting device”, a waterless solar panel cleaning device designed specifically for use in harsh desert environments. Once a day, Nomadd pushes dust and dirt away from panel surfaces with an automated “dry sweep.” It can even clean the thick dust that sticks after a rain shower or sand storm in humid conditions.
“Basically it can clean solar panels without water. It’s a brand new solution to a brand new problem,” says German-Australian engineer Georg Eitelhuber, a physics teacher at the King Abdullah University of Science and Technology (Kaust) in Saudi Arabia, who invented the ingenious device.
“This whole project started with Lego and toilet rolls,” Eitelhuber says of his early days prototyping the Nomadd in after-school experiments. “And now the idea’s gone up to some pretty high levels in the Saudi government. It’s kind of crazy”
Nomadd is as simple, rugged and low-maintenance as possible, with just four major moving parts. Eitelhuber is reluctant to reveal too many details, as he has various patents pending. However, he says the device is designed to run along a bank of solar panels, sweeping away the dust. It is powered by lithium-ion batteries, charged by the array and is able to maneuver over gaps and obstacles between the panels. It can be used as often as desired- either automatically on a schedule, or instantly with the touch of a button in a remote control station.