Scientists from MIT developed a method that uses static electricity to keep solar panels free of dust, removing the need for constant cleaning with water, a blog post from MIT explains.
Solar panels are a shining light for renewable energy initiatives worldwide, but the technology does have some problems. Take, for example, the fact that recycling is an issue, just as the first generation of solar panels comes to the end of its lifespan.
Then there's the massive amount of water required to clean solar panels. According to MIT, solar panels' output is reduced by constantly accumulated dust, meaning regular cleaning is essential. Due to this requirement, the cleaning of solar panels is estimated to use about 10 billion gallons of water each year — which would be enough to provide drinking water to 2 million people.
The MIT team's waterless, no-contact system uses electrostatic repulsion to make dust particles effectively jump off the panel's surface. To make this happen, an electrode in the form of a metal bar is passed over the panel's surface, giving the dust particles an electrical charge. A charge is then applied to the solar panel, which repels the dust particles, causing them to leap off into the air and away from the panel.
Dust can "obliterate" the solar power industry's output
The new system can be operated automatically on a timer using an electric motor and guide rails on the panel's side that would pass the electrode over the panel without directly touching the surface.
It is described in a paper in the journal Science Advances, written by MIT graduate student Sreedath Panat and professor of mechanical engineering Kripa Varanasi.
In their paper, the researchers explain that, globally, a three to four percent reduction in power output from solar panels would equal a loss of $3.3 billion and $5.5 billion in revenue. Their research showed that dust can inhibit solar panel operation by up to 30 percent in only a month without cleaning.
"There is so much work going on in solar materials," Varanasi explained. "They're pushing the boundaries, trying to gain a few percent here and there in improving the efficiency, and here you have something that can obliterate all of that right away."
The researchers say their method would reduce the reliance for water to be trucked into desert regions to clean massive solar panel farms — an issue that currently detracts from their role as a sustainable alternative for producing energy. Not only that, it could greatly reduce the costs for operators, which currently have to assign roughly 10 percent of expenditure to cleaning their panels with water.