New electrostatic concept keeps panels clean while conserving resources
One concern we often hear from homeowners who are first learning about solar is that solar panels will require difficult cleaning and maintenance in order to operate at full efficiency. Nobody likes the idea of having to climb up on their roof on a regular basis to clean their solar panels! Fortunately, those concerns are largely unfounded – an occasional quick spray with a good hose from ground level is all the “maintenance” most rooftop residential solar installs need.
For ground-mounted solar panels, cleaning is a bit more of a concern. Although ground-mounted panels, like rooftop ones, are typically mounted at an angle which allows debris such as fallen leaves to slide off, buildup of dust and dirt is inevitably more prevalent. In a relatively small, residential system, this may seem like no big deal. For utility-scale solar installations that use acres of ground-mounted panels, it’s a different story. Cleaning takes on even greater significance when we consider the fact that many large-scale ground-mount solar “farms” are located in desert areas where sunlight is abundant, but dust is as well – while water for cleaning panels is obviously scarce.
Researchers at MIT are working on one possible solution to the problem of keeping ground-mounted solar panels clean without having to invest so much in labor and resources that it compromises solar’s eco-friendly impact. Their system is based on the principle of electrostatic repulsion. By imparting a positive electric charge to the particles of dust which accumulate on a solar panel’s surface, and a negative charge to the panel itself, the system causes the dust to simply lift away without the need for spraying or scrubbing.
Cleaning solar panels currently uses billions of gallons of water every year – enough to supply drinking water, it’s estimated, for 2 billion people. Worse, in desert areas, all of that water has to be trucked in from a long distance away. Perfecting a water-less cleaning system that could be applied to even a fraction of the ground-mount solar panels currently in use would allow that water to be redirected to other uses.
With solar panel technology having reached a high level of maturity, much of the research in the solar space is focused on ways to make utilizing solar technology on a large scale easier. Although panel technology itself will continue to improve in areas like efficiency, finding ways to reduce the amount of resources needed to deploy and maintain solar could unlock much more potential. Keeping ground-mount solar panels in large-scale installations clean without having to transport and expend precious water is one way that solar can have an even greater positive sustainability impact.