London-based startup Aerial Power is looking to help reduce the burden with brush-carrying drones that skim along the solar arrays and wipe their surfaces clean.

This isn't the first time automated upkeep of solar panels has been tackled. In 2009, the Californian company Heliotex developed a cleaning system that sprays water through nozzles installed on each panel at intervals determined by the user. Earlier this year, Israel's first solar field Ketura Sun deployed a fleet of robots that move up and down the panels, using a rotating brush to keep them dust-free.

Keeping these surfaces clear of dirt can improve energy production by as much as 30 per cent each month, according to Aerial Power. The expensive and time-consuming nature of cleaning the panels manually often means the task is neglected, rendering the systems less efficient than they might otherwise be. Aerial Power is aiming to reduce these maintenance costs by 70 percent.

The solution uses a so-called SolarBrush, a drone attachment that sweeps across the surface of the panels, brushing dirt and dust to the ground below. Ridha Azaiz, a German engineer and founder of Aerial Power, says one advantage of his solution over other robot cleaning systems is that it can cover an entire solar farm through pre-programmed flight paths. This means they don't need to be moved manually from row to row, a task which in itself can prove labor-intensive.