Mars technology creates self-dusting solar panels

Self-cleaning technology developed for lunar and Mars missions could be used to keep terrestrial solar panels dust free

Dust deposits can reduce the efficiency of electricity generating solar panels by as much as 80%.

The self cleaning technology can repel dust when sensors detect concentrations on the panel's surface have reached a critical level.

The research was presented at a meeting of the American Chemical Society.

Large scale solar installations are usually in sunny, dry desert areas where winds can deposit layers of dust over the solar panels.

Solar panels in the Mojave desert cover many kilometres. In one month, dust fall can reach as much as 17kg per square kilometre.

The dust reduces the amount of light that enters the panels and so the electricity they can generate.

Cleaning dust manually is not practical because of the scale of the installations and the scarcity of water in desert regions. Keeping them clean is a major headache for the companies deploying the installations.

Working with Nasa, Malay Mazumder from Boston University originally developed the technology to keep solar panels powering Mars rovers clean.

The self cleaning technology uses a layer of an electrically sensitive material to coat each panel.

Sensors detect when dust concentrations reach a critical level and then an electric charge energises the material sending a dust-repelling wave across its surface.

Mazumder says that this can lift away as much as 90% cent of the dust in under two minutes and only uses a small amount of electricity

There are large scale solar installations generating electricity in the United States, Spain, Germany, the Middle East, Australia and India.

Dust deposition rates are highest in the Middle East, Australia and India.

Mazumder believes his is the only automatic dust-busting technology that does not need water or any kind of mechanical movement.

While currently less than 0.04% of global energy production comes from solar panels, the popularity of solar energy is increasing. The use of solar panels went up by 50% between 2003 and 2008.

Mazumder and colleagues hope the self cleaning technology could play an important role in increasing the efficiency and reducing maintenance costs of generating electricity from sunlight.

They expect the technology to be commercially available within one year.