Transparent Solar Panels Are “The Wave of the Future”

Researchers from Michigan State University believe transparent solar panels have the potential to generate just as much solar power as rooftop solar panels. When used effectively, they could at full implementation provide 40 percent of electricity in the U.S.

See-through Solar Panels

Solar panels and solar power-generating windows are a couple of things people have come up with to take advantage of the Sun, but now a team of engineering researchers from Michigan State University (MSU) have proposed the use of transparent solar panels. Combined with rooftop panels, our reliance on fossil fuels could be greatly reduced and we’d be close to meeting the United States’ high electricity demand.

Led by Richard Lunt, the Johansen Crosby Endowed Associate Professor of Chemical Engineering and Materials Science at MSU, the team created a transparent luminescent solar concentrator that could generate solar energy on any clear surface without affecting the view. In theory, it could be applied to cell phones, windows, buildings, and cars.

“Highly transparent solar cells represent the wave of the future for new solar applications,” said Lunt. “We analyzed their potential and show that by harvesting only invisible light, these devices can provide a similar electricity-generation potential as rooftop solar while providing additional functionality to enhance the efficiency of buildings, automobiles and mobile electronics.”

Growing Potential

Currently, according to Lunt and his team, only 1.5 percent of electricity in the U.S. is generated by solar power. Transparent solar panels, however, could account for 40 percent of electricity, provided its used on the 5-7 billion square meters of glass surface in the country — something that’s unlikely to happen anytime soon.

Before they can even be considered, they need to be more efficient. Compared to solar panel’s 15 percent efficiency, transparent panels are only 5 percent efficient. Despite this, Lunt states that transparent panels are only about a third of the way into their full potential after five years’ research. Going forward, work will be done to improve the panel’s capabilities, though they’re not expected to outperform or replace the traditional solar panels we’ve become accustomed to.

“Ultimately, this technology offers a promising route to inexpensive, widespread solar adoption on small and large surfaces that were previously inaccessible,” added Lunt.

 

Led by engineering researchers at Michigan State University, the authors argue that widespread use of such highly transparent solar applications, together with the rooftop units, could nearly meet U.S. electricity demand and drastically reduce the use of fossil fuels.

“Highly transparent solar cells represent the wave of the future for new solar applications,” said Richard Lunt, the Johansen Crosby Endowed Associate Professor of Chemical Engineering and Materials Science at MSU. “We analyzed their potential and show that by harvesting only invisible light, these devices can provide a similar electricity-generation potential as rooftop solar while providing additional functionality to enhance the efficiency of buildings, automobiles and mobile electronics.”

Lunt and colleagues at MSU pioneered the development of a transparent luminescent solar concentrator that when placed on a window creates solar energy without disrupting the view. The thin, plastic-like material can be used on buildings, car windows, cell phones or other devices with a clear surface.

The solar-harvesting system uses organic molecules developed by Lunt and his team to absorb invisible wavelengths of sunlight. The researchers can “tune” these materials to pick up just the ultraviolet and the near-infrared wavelengths that then convert this energy into electricity.

Moving global energy consumption away from fossil fuels will require such innovative and cost-effective renewable energy technologies. Only about 1.5 percent of electricity demand in the United States and globally is produced by solar power.

But in terms of overall electricity potential, the authors note that there is an estimated 5 billion to 7 billion square meters of glass surface in the United States. And with that much glass to cover, transparent solar technologies have the potential of supplying some 40 percent of energy demand in the U.S. – about the same potential as rooftop solar units. “The complimentary deployment of both technologies,” Lunt said, “could get us close to 100 percent of our demand if we also improve energy storage.”

Lunt said highly transparent solar applications are recording efficiencies above 5 percent, while traditional solar panels typically are about 15 percent to 18 percent efficient. Although transparent solar technologies will never be more efficient at converting solar energy to electricity than their opaque counterparts, they can get close and offer the potential to be applied to a lot more additional surface area, he said.

Right now, transparent solar technologies are only at about a third of their realistic overall potential, Lunt added.

“That is what we are working towards,” he said. “Traditional solar applications have been actively researched for over five decades, yet we have only been working on these highly transparent solar cells for about five years. Ultimately, this technology offers a promising route to inexpensive, widespread solar adoption on small and large surfaces that were previously inaccessible.”