Perovskite continues to score points to become a key element of the solar panels of the future. Its qualities for the absorption of light and its low price do not go unnoticed by researchers, who have turned to this material and who have just announced a world record of efficiency with a cell that combines this product and silicon. Specifically, the energy conversion efficiency has reached 23.9%.
The achievement has come from the Belgian research institute IMEC. This center has been exploring this technology for some time in collaboration with Solliance, a group of Dutch, German and Belgian R&D entities, and with Energy Ville, an association that brings together several research centers specialized in sustainable energy.
In fact, the announcement comes just over a month after another research group, in this case from the Korean university UNIST, raised the efficiency bar to 22.1% for perovskite solar cells. For this advance, which was then described as an unprecedented milestone, an organic-inorganic hybrid was used.
While the Asian researchers achieved that result with a one-square-centimeter cell, the Belgian institute achieved that level of conversion efficiency with 4-cm² modules. The advance of the IMEC, the institution assures, is incomparable in efficiency, which also surpasses that of a silicon cell.
Regardless of who is closer to the finish line in this race to put an end to one of the main brakes on perovskite for use in solar energy collection systems -the loss of performance-, these works suggest that the The time when it can be used on a commercial scale is getting closer. When that point is reached, the industry may turn around, especially in terms of production and selling costs, which would be significantly reduced.
Until then, the IMEC now holds that record for energy conversion efficiency. It has achieved this about a year after presenting a semitransparent pervoskite module on a crystalline silicon cell that, at that time, had an efficiency of almost 20% (20.2%).
Now, the researchers have managed to improve their own results by up to 3.7 percentage points. For this, the key is in two innovations. The first, the use of another type of perovskite (CsFAPbIBr, in the current module) that “greatly improves the stability and conversion efficiency of perovskite modules,” according to Tom Aernouts, researcher in charge of thin-film photovoltaics at the IMEC and responsible for the perovskite program at Solliance.
In addition to opting for another perovskite, the new result is explained thanks to an optimization of the architecture of the panel stack. Specifically, an anti-reflective texture and a liquid with a refractive index according to the perovskite and silicon have been incorporated into the module. With this, it has been possible to reduce optical losses.
In addition to the results obtained with this panel, the IMEC claims to have achieved an energy conversion efficiency of up to 25.3%, but with a smaller size and “less attractive from the point of view of the industry.” This is how Aernouts considers it who, however, points out that the improved performance panel increases the attractiveness of manufacturing this technology from perovskite, a material cheaper than silicon, dominant today in the industry.
More information at IMEC.