Scientists from Sweden and China have developed an organic solar cell that converts ambient indoor light into electricity.
As the inter-connectivity of WIFI enabled devices increases scientist expect a rise in online products, specially sensors monitoring moisture, particle concentrations and temperature. This new wave of electrical products highlights a growing demand for smaller and cheaper sources of renewable energy.
The flexible organic solar cells, developed by Linköping University, Sweden, are cheap to manufacture. With the light absorbing layer consisting of a mixture of donor and acceptor material, the solar cell is able to be tuned to absorb light from different wavelengths of light.
Lead researchers Jianhui Hou, from Beijing, and Feng Gao, from Linköping University, have developed a combination of donor and acceptor materials with a carefully determined composition, to be used as the active layer in the solar cell.
The research identified two variants of the organic cell. One variant has an area of 1 cm2 and the other 4 cm2. The smaller solar cell was exposed to ambient light at an intensity of 1000 lux, and the researchers observed that as much as 26.1% of the energy of the light was converted to electricity. The organic solar cell delivered a high voltage of above 1 V for more than 1000 hours in ambient light that varied between 200 and 1000 lux. The larger solar cell still maintained an energy efficiency of 23%.
“This work indicates great promise for organic solar cells to be widely used in our daily life for powering the internet of things”, says Feng Gao, senior lecturer in the Division of Biomolecular and Organic Electronics at Linköping University.
”We are confident that the efficiency of organic solar cells will be further improved for ambient light applications in coming years, because there is still a large room for optimisation of the materials used in this work”, Jianhui Hou, professor at the Institute of Chemistry, Chinese Academy of Sciences, underlines.