Perovskite just got one step closer to redefining solar power technology.
A team of researchers from Princeton University has built the first perovskite solar cells that last long enough to be commercially viable, according to a paper published today in the journal Science.
This is a huge advancement that could herald a major shift in renewable energy technology. For the first time, a material that converts sunlight directly into electricity appears poised to compete with silicon-based cells.
In case you didn't know, silicon-based cells, which many regard as an expensive and suboptimal component, have dominated the renewable energy market since their introduction in 1954. This new technology, which is not only incredibly durable but also meets common efficiency standards, has the potential to change that.
The technology is expected to outperform industry norms for roughly 30 years, well beyond the 20-year criterion for solar cell viability, according to a press release.
Perovskite solar cell vs. Silicon-based cell
Pioneered in 2006, perovskite solar cells are regarded as high-efficiency, low-cost modular technology for implementation in the renewable power industry. That's because perovskites are semiconductors with a unique crystal structure that makes them particularly ideal for solar cell technology.
For starters, perovskites can be manufactured at room temperature. This means they need far less energy than silicon, making them less expensive and more environmentally friendly to make.
There is also the fact that silicon is stiff and opaque. Perovskites, on the other hand, can be modified to be flexible and transparent. This, however, renders them fragile: the press release states that the early perovskite solar cells developed between 2009 and 2012 lasted barely minutes.
Overcoming these challenges and commercializing cheap perovskite films could potentially disrupt the solar power market by pushing solar cell technology beyond the boundaries of silicon, and the new device from the Princeton University might achieve just that.
A new method
Remarkably, the new device's estimated lifetime is a five-fold increase over the previous record, which was established by a lower efficiency perovskite solar cell in 2017. According to the researchers, however, their accelerated aging technique might actually be more significant than their new device.
That's because long-term testing has actually been avoided until recently. This was due to the fragility of perovskites; however, as they improve with time, finding a way to test the different design architectures and make these tests more sophisticated will surely become increasingly important.
"We might have the record today, but someone else is going to come along with a better record tomorrow," Lynn Loo, the Theodora D. '78 and William H. Walton III '74 Professor in Engineering who led the study, said in a press release. "The really exciting thing is that we now have a way to test these devices and know how they will perform in the long term.”
The record-setting new device
The new testing method enabled researchers to see the aging process of the device by blasting it with heat. The researchers chose four aging temperatures and measured outcomes over four independent data streams, ranging from a regular summer day's baseline temperature to an extreme of 230 degrees Fahrenheit (110 degrees Celsius).
Overall, they found that the device will run at or above 80 percent of its peak efficiency under continuous illumination for at least five years at an average temperature of 95 degrees Fahrenheit (35 degrees Celsius).
According to Loo, that is the equivalent of 30 years of outdoor operation in a city like Princeton, New Jersey. As the researchers certainly wouldn't be able to test their device for 30 years, the new method is certainly a significant addition to the field of solar power.
"This paper is likely going to be a prototype for anyone looking to analyze performance at the intersection of efficiency and stability,” Joseph Berry, a senior fellow at the National Renewable Energy Laboratory who was not involved in the study, said, in the press release. "By producing a prototype to study stability, and showing what can be extrapolated [through accelerated testing], it’s doing the work everyone wants to see before we start field testing at scale. It allows you to project in a way that’s really impressive."