The technology is in the form of semitransparent organic solar cells (based on hydrocarbons) added to eyeglasses in order to power a microprocessor. This could become the basis of future solar-powered mobile applications. An important advantage is with organic solar cells being flexible, transparent, and light-weight. With an eye towards commercialization and with a nod towards the fashion industry, the cells can be produced in a range of shapes or colors, in a way that is not possible using conventional silicon solar cells. In addition the power generated from organic solar cells is far greater than would be possible from conventional photovoltaics.
The prototype invention, from the Karlsruher Institut für Technologie, is a pair of sunglasses with colored, semitransparent solar cells. The cells are applied onto lenses that supply a microprocessor as well as two displays with electric power. The glasses were developed by a team led by Dr. Alexander Colsmann, who serves as the Head of Organic Photovoltaics Group at the university’s Light Technology Institute.
The “smart” solar glasses are self-powered to measure and display the solar illumination intensity and ambient temperature. The solar cell lenses have a thickness of around 1.6 millimeters and they weigh just six grams; which is not dissimilar from lenses found in traditional sunglasses. The microprocessor, together with two tiny displays, is integrated into the upper region of the solar glasses.
The displays indicate the illumination intensity and the ambient temperature in the form of histograms. While greater power capture occurs outside, the glasses have also been shown to function inside under illumination down to 500 Lux (as found in a typical office). Even inside the “smart” lenses can generate 200 milliwatts of electric power. This would be sufficient power to operate technology like a hearing aid or fitness tracker.
The technology does not stop at sunglasses. The success of the research paves the way for other applications, such as the integration of organic solar cells into windows or the use of the cells to in overhead glazing, for transforming the absorbed light into electric power. In theory large surfaces could be coated with organic solar cells using reel-to-reel technology.
The research is published in the journal Energy Technology, with the research paper titled “Solar Glasses: A Case Study on Semitransparent Organic Solar Cells for Self-Powered, Smart, Wearable Devices.”