technology

The glasses that could charge your phone: Transparent solar cells could even turn windows into power plants
Organic solar cells - which use energy from the sun to generate electricity - are unique in that they're transparent and light-weight, and can be manufactured in different shapes and colors.

They can be used for a wide range of applications that can't be done with conventional silicon solar cells, which are heavier and more rigid.

The glasses, made by researchers at the Karlsruhe Institute of Technology, were designed as a case study demonstrating how organic solar cells can be used.

'We bring solar power to places where other solar technologies fail,' says Dr Alexander Colsmann, Head of Organic Photovoltaics Group at KIT's Light Technology.

The 'smart' Solar Glasses are self-powered to measure and display the degree of solar illumination and the temperature, and they also work in indoor environments under illuminations as low as 500 Lux - the usual illumination level of an office or living area.

Even under indoor conditions, the lenses are capable of each generating 200 microwatt's of electric power - enough to operate devices such as a hearing aid or a step counter.

The solar cell lenses were fitted to a commercial frame and have a thickness of about 1.6 millimeters (0.06 inches) and weigh six grams (0.2 ounces), similar to the lenses of traditional sunglasses.

The microprocessor and the two displays are integrated into the temples of the Solar Glasses, showing the illumination intensity and ambient temperature as bar graphs.