A Transparent Glass That Generates Solar Energy

Happy Nagashetti on August 21, 2014 at 12:12 pm

We have lots of avenues from where we can generate energy without having to touch the biochemical fuel made of prehistoric organisms. There is tremendous potential in the Sun and Wind to generate electricity. But the roof mounted solar cells are  passé, its time to let the modern glass based architecture, pay for themselves and their maintenance costs by covering them with transparent solar concentrators.

Researchers at the Michigan State University have developed transparent solar energy concentrators that can someday be used as window glass. Not just that, it can be used to make display panels for mobile phones or devices with flat surfaces. So you can easily imagine a future where phones will be able to charge themselves. Talk about a revolutionary idea. The study was featured in the journal Advanced Optical Materials.

The technology can be used to make windows that can generate energy for the office

There have been previous efforts into the technology, but most of the time the material in the end was either too inefficient or was colored. A solar concentrator glass needs to be transparent to have some practical value. Most of the glass around us is transparent and colored glass can only be used for decorative purposes and not on office windows.

The new glass material has been developed by Richard Lunt, assistant professor of chemical engineering and materials science, and his team. The material used in this transparent concentrator uses small organic molecules to absorb specific non-visible wavelengths of sunlight. These materials do not absorb light from the visible spectrum and hence appear transparent.

These panels can be tuned to pick up light from ultraviolet and near-infrared wavelengths that then glow at another wavelength of infrared. This glowing infrared light is then directed towards the edge of the panel where it is used to generate electricity using photovoltaic cells.

The ultimate intention of the research team is to make unobtrusive and almost invisible. This will also ease out the process of creating an off grid system where buildings can generate the electricity they need on their own.

As the project is still in the first steps, the efficiency of these concentrators is at roughly 1 percent. The panel is expected to achieve 5 per cent efficiency when fully optimized. For some perspective, it’s important to know that even the most capable colored concentrator has an efficiency of about 7 per cent. This just tells us that we still have to make huge strides in unlocking the full potential of the sun.