New Solar Cell Which Can Be Used In Windows

Scientists have developed a semi-transparent solar cell that offers a reasonable level of efficiency. This might get us closer to the solar energy window concept and could revolutionize architecture and energy production. This research was done by researchers and engineers from Monash University, CSIRO Manufacturing and Melbourne Centre for Nanofabrication.

The researchers have said that two square meters of the next-gen perovskite solar cells (PSCs) would be enough to generate about as much electricity as a standard solar panel in the region of 140 watts per meter if tinted to the same degree as current glazed commercial windows.

Solar cell windows have been an area of development for years, but the major problems in this area are the efficiency, stability, and cost. The team behind the new project says they are closer than ever to doing just that.

“Rooftop solar has a conversion efficiency of between 15 and 20 percent,” says materials chemist Jacek Jasieniak, from Monash University in Australia. “The semi-transparent cells have a conversion efficiency of 17 percent, while still transmitting more than 10 percent of the incoming light, so they are right in the zone“.

“It’s long been a dream to have windows that generate electricity, and now that looks possible.“

The main thing in this work is the replacement of an important solar cell component (Spiro-OMeTAD to be technical) with a newly developed special polymer, based on an organic semiconductor, which increases overall stability.

Though the research seems pretty attractive, there is still some gap. Still, you won’t be able to gaze through a perfectly clear window and get the maximum amount of energy efficiency from it. There is a need to find a balance between opacity and efficiency.

“There is a trade-off,” says Jasieniak. “The solar cells can be made more, or less, transparent. The more transparent they are, the less electricity they generate, so that becomes something for architects to consider.“

Even with this major step forward, it may take as much as 10 more years for the tech to be commercialized and scaled up. The scientists are working with business partners to try and get the solar cells included in future building plans.

Multi-storey buildings, where glazing is already expensive, are going to be the first beneficiaries, according to the team, as the addition of solar cell technology won’t cost a huge amount extra (and don’t forget the electricity savings).

Among the avenues that the researchers are now exploring is combining a layer of perovskite solar cells with a layer of organic solar cells (the more traditional type) to get the benefits of both.

“These solar cells mean a big change to the way we think about buildings and the way they function,” says Jasieniak.

“Up until now every building has been designed on the assumption that windows are fundamentally passive. Now they will actively produce electricity.“

Journal Reference
1. Semi-transparent perovskite solar cells with a cross-linked hole transport layer
DOI: 10.1016/j.nanoen.2020.104635