The world of solar energy is on the verge of a transformation, as researchers develop a new class of solar cells using materials with higher conversion efficiency than those found in today’s panels.
The Shift to Perovskite Solar Cells
Currently, most solar panels are made from silicon and operate at an efficiency rate of around 22%. This means they can convert only about one-fifth of solar energy into electricity, as silicon absorbs a limited range of sunlight wavelengths. In addition, silicon production is both costly and energy-intensive.
Recently, CleanTechnica reported that researchers at the University of Colorado Boulder, working with international collaborators, have unveiled a new method for manufacturing perovskite solar cells. This marks an important step toward the commercial viability of what many consider the next generation of solar technology.
Michael McGehee, a professor in the Department of Chemical and Biological Engineering and a fellow at CU Boulder’s Renewable & Sustainable Energy Institute, believes perovskites could be a significant breakthrough.
To boost performance, researchers have been experimenting with stacking perovskite solar cells on top of traditional silicon cells. This creates “tandem” cells that could increase panel efficiency by over 50%, as each material absorbs a different part of the sun’s spectrum.
McGehee explained that improving the efficiency of solar cells is essential to support the ongoing shift toward electrification. A significant obstacle to commercializing perovskite cells, however, has been the coating process, which requires a nitrogen-filled environment to prevent oxidation.
perovskite solar cells
A Breakthrough Additive for Stability
McGehee and his team discovered that adding dimethylammonium formate (DMAFo) to the perovskite solution prevents oxidation, allowing the cells to be coated in ambient air.
This breakthrough allows the new perovskite cells to achieve efficiencies of nearly 25%—comparable to the current record of 26%—without a nitrogen-filled environment.
For comparison, commercial silicon panels typically lose about 1% of their efficiency annually, maintaining around 80% after 25 years. Perovskite cells, however, degrade much faster due to their reactivity in air.
The study found that perovskite cells containing DMAFo retained 90% of their efficiency after 700 hours of simulated sunlight, while cells without the additive began to degrade rapidly after just 300 hours.
While these results are promising, more long-term testing is needed to fully assess stability. McGehee emphasized that although it’s premature to claim these cells are as stable as silicon panels, the findings point in the right direction.
The Path to Commercialization
This research brings the commercialization of perovskite solar cells a step closer. McGehee’s team is now developing tandem cells that could exceed 30% operational efficiency while matching the longevity of silicon panels.
His team heads the U.S. partnership TEAMUP and has received $9 million from the Department of Energy to create stable tandem perovskites for real-world use. The goal is to develop cells that outperform traditional silicon panels over a 25-year span.
More efficient and potentially more affordable, these tandem cells could be used in a variety of applications, such as on electric vehicle roofs, where they could provide an extra 15 to 25 miles of range per day.
After just a decade of research, engineers have developed perovskite cells with efficiencies comparable to silicon—a technology that has been refined for 70 years. McGehee is confident in their potential, predicting that with successful tandem cell development, perovskites could dominate the solar market.