Skyscrapers are incredible structures merely in regard to their height alone. Some look at skyscrapers and see a world of opportunity in terms of their usage – but others see untapped potential. Lance Wheeler, #solar power expert at the National Renewable #Energy Laboratory, says that office buildings and homes account for ¾ of electricity usage in America, and 40 percent of overall energy usage. Windows are a portion of the issue because they leak energy.
Taking Windows to Solar Heights
Wheeler believes that one solution is to turn windows into solar panels. Scientists have previously embedded films that absorb light in window glass. The downfall? These “#solar windows” have a color that many find unappealing. Newer solar technologies would be able to block the infrared radiation and UV using clear glass. Heat gain would be cut while power is generated thanks to these solar windows, so they have a great deal of potential. As a matter of fact, these solar panel windows could lead a #skyscraper to being able to power itself.
Typical crystalline silicon cells tend to govern the industry today, and #solar cells are similar in some ways. Top silicon cells boast 25 percent efficiency, while a new class of opaque solar cell materials are demonstrating efficiencies of 22 percent. Why does it matter? Well, to start, the opaque solar cell materials are less expensive in comparison to silicon. Secondly, they can be made to absorb certain light frequencies merely by altering their chemical formula.
Richard Lunt led a team that recently reported it was able to tune materials to formulate a perovskite solar window that absorbs UV and has a .5 percent efficiency. While this number might be well under the efficacy of some of the top perovskite solar cells, it just so happens to be sufficient to power a different window technology – darkening glass, which stops penetrating light at the hottest times of the day, and lessens a building’s requirements for air conditioning. In Richard Lunt’s opinion, his team can get to higher efficiencies in the near future (likely 4 percent over the next few years). This is significant because the solar cells would have the ability to power a portion of the air conditioning and even lights for the building.
Infrared Light: Can It Generate More Electricity?
Infrared light is able to produce more electricity because of the way it intensely strikes the surface of the Earth. It can produce more electricity than UV light. According to Lunt, forthcoming systems that “yoke UV-capturing perovskites to infrared-capturing organics could get to efficiencies of 20 percent.” While this is fascinating in itself, these systems could still be almost totally transparent. Wow!
Affordable Solar Windows
Another approach when it comes to clear solar windows is dependent on luminescent solar concentrators. How would this work? Small semiconductor particles, or #quantum dots, absorb light at infrared and UV frequencies and re-release it at wavelengths that traditional solar cells capture. This light, which is re-emitted, is concentrated through the glass to solar cell strips that are fixed in the frame of the window. These small semiconductor particles are inexpensive to create and a minimal amount of solar cell material is required to catch the light which has been re-emitted. Therefore, these solar windows would not be expensive. Solar cells function best under concentrated light.
Stanford University solar windows and perovskites expert, Michael McGehee, says that the idea of semitransparent windows shouldn’t be thrown out yet.
In 2017, $2.5 million was awarded by the U.S. Department of Energy to Next Energy Technologies in California in order to improve its transparent organic solar cell windows. The corporation stands out because it has been able to reach efficiencies of 7 percent using windows that absorb 50 percent of the incident sunlight which hits them. And they don’t change to an unappealing color because they are able to absorb light from across the spectrum.
The technology which will come out on top is unclear at this point. Something to consider is toxicity. Where does toxicity come into play? Simply put, a large number of solar windows are made of a minimal quantity of toxic components – and glass can break. This is just one drawback to consider. Considering windows will be used on buildings and skyscrapers anyway, doesn’t it make sense to try to improve them? Could see-through solar cells be the answer? Follow solar news to learn more about solar cells and how buildings could potentially generate their own power in the future!