Quenching the thirst of concentrated solar power plants

Concentrated solar power - CSP - has the potential to bring energy to remote areas of the world. The heat of the sun is reflected off rows of mirrors onto a central tower, transforming water into steam and turning a turbine which then generates electricity.But these plants have a fatal flaw - they are extremely thirsty.This type of solar energy is perfectly suited to deserts with their strong sunlight, but desert sand and dust mean all the mirrors need regular cleaning - using precious water.Cleaning the gigantic mirrors also uses lots of liquid. Researchers are testing an ultrasonic cleaning system, which uses less water, as part of an EU project.