A study led by engineers at Michigan State University says that the use of transparent solar cells could potentially fulfill roughly 40 percent of the United States’ energy demands, the equivalent of the potential for bulkier rooftop solar units, if applied to the abundant area of glass available in the US.

"Highly transparent solar cells represent the wave of the future for new solar applications," explains Richard Lunt, an Associate Professor with MSU’s Chemical Engineering and Materials Science. "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’s team is responsible for pioneering the development of a transparent luminescent solar concentrator, that can be applied to a glass surface such as a window, without obscuring the glass’s transparency. Their new study estimates that there is 5 billion to 7 billion square meters of glass surface in the United States (between 53.8 billion and 75.3 billion square feet) — a massive area with a lot of electricity-generating potential.

Although the efficiencies of transparent solar cells aren’t nearly as good as traditional photovoltaic cells (5 percent, versus 15-18 percent), the sheer area that could be covered would mean that the accumulated output could match their opaque counterparts. "The complimentary deployment of both technologies," according to Lunt, "could get us close to 100 percent of our demand if we also improve energy storage."