Scientists have come up with a new way to clean solar panels without using water. 

Solar power is expected to reach 10 percent of global power generation by the year 2030, and much of that is likely to be located in particularly hot and dry areas. 

Accumulation of dust on solar panels or mirrors is a major issue, as it can reduce the output of photovoltaic panels by as much as 30 per cent in just one month without cleaning.

Regular cleaning is needed for the giant installations, meaning many solar farms require significant amounts of water. 

Cleaning solar panels is currently estimated to use enough water for up to 2 million people. 

But now, a team of researchers at MIT has devised a way of automatically cleaning solar panels, or the mirrors of solar thermal plants, in a waterless, no-contact system that could significantly reduce the dust problem, they say.

The new system uses electrostatic repulsion to cause dust particles to detach and virtually leap off the panel’s surface, without the need for water or brushes. 

To activate the system, a simple electrode passes just above the solar panel’s surface, imparting an electrical charge to the dust particles, which are then repelled by a charge applied to the panel itself. 

In practice, at scale, each solar panel could be fitted with railings on each side, with an electrode spanning across the panel. A small electric motor, perhaps using a tiny portion of the output from the panel itself, would drive a belt system to move the electrode from one end of the panel to the other, causing all the dust to fall away. 

The whole process could be automated or controlled remotely. Alternatively, thin strips of conductive transparent material could be permanently arranged above the panel, eliminating the need for moving parts.

Water cleaning makes up about 10 percent of the operating costs of solar installations. The new system could potentially reduce these costs while improving the overall power output by allowing for more frequent automated cleanings, the researchers say.

More details are accessible here.