How transparent solar panels + 'quantum dots' could harvest energy on an architectural scale
Imagine a glass skyscraper that, instead of using energy, stands as source of power for the entire building. Although this sounds like the city of the future, recent developments mean that it could soon be a reality — at least in part. the key lies in the creation of transparent solar cells which, when placed between the panes of double-glazed windows, inconspicuously harvest energy from the sun. However, a major challenge for scientists is maximizing the cell’s energy efficiency without compromising transparency.
In August 2020, a team led by University of Michigan researchers set a new efficiency record for color-neutral, transparent solar cells. The team achieved 8.1% efficiency and 43.3% transparency with an organic, or carbon-based, design rather than conventional silicon. While the cells have a slight green tint, the team says that they are much more like the gray of sunglasses and car windows.
‘Windows, which are on the face of every building, are an ideal location for organic solar cells because they offer something silicon can’t, which is a combination of very high efficiency and very high visible transparency,’ explains Stephen Forrest, the Peter A. Franken distinguished university professor of engineering and Paul G. Goebel professor of engineering. Forrest led a team that includes researchers at North Carolina state university, Soochow university in China, and SLAC national accelerator laboratory.