I told you long ago, in one of the most read posts on the blog, the ranking of the tallest skyscrapers in the world. Imagine that all that sea of glass is able to gather energy from the sun.
It's a futuristic vision that could soon become reality. The key is creating transparent solar panels that, when placed in windows, collect energy from the sun. Basically the solar version of Harry Potter's invisibility cloak.
Even smartphone displays could be equipped with these panels to recover some of the energy, and extend battery life.
Transparent solar panels: new efficiency record
Researchers have set new performance records for neutral-colored transparent solar cells. Today we are at 8,1% efficiency: it is a crazy leap if you consider the previous 2-3%. Transparency also sets an efficiency record with 43,3%, thanks to an organic design based on carbon rather than conventional silicon.
Currently the glass on the facades of skyscrapers has a coating that serves to reflect and absorb some of the light to reduce the brightness and heat inside. Instead of throwing this energy away, transparent solar panels could harness it.
“Windows, found on the facade of every building, are an ideal location for organic solar cells because they offer something that silicon cannot. A combination of very high efficiency and very high visible transparency”, they explain Stephen Forrest, university professor of engineering and Paul G. Goebel, professor of engineering.
Towards the next milestone
UbiQD, a New Mexico advanced materials company, continues its development of solar panels that are transparent and indistinguishable from regular glass. The secret is the use of Quantum Dots, “quantum dots”. Microscopic particles that have the ability to manipulate light to harness energy.
These are super nanoparticles of material: to cover the surface of a nail it would take around 100.000 of them. This technology can be a game changer in reducing massive loads from large power grids and perhaps even be an integral part of planning future cities that will run on solar energy.
