Perovskite solar cells have captured the attention of researchers around the globe with the allure of next-level improvements in cost, weight, flexibility, and range of applications compared to conventional silicon solar cells. The technology still has some road to travel before it hits the mass market an that could include a shortcut through outer space, if all goes according to plan.
Exciting News About Perovskite Solar Cells
CleanTechnica has been spilling lots (and lots) of ink on the potential for perovskite technology to push the affordability envelope on solar power. The connection to outer space is especially exciting because space exploration was the original engine that galvanized the development of the commercial solar industry in the 2oth century.
NASA launched its first silicon solar cells on board the Vanguard 1 in 1958, just four years after researchers at the Bell Labs campus in New Jersey demonstrated the first photovoltaic cell designed for practical use.
The single crystal silicon solar technology sported by Vanguard 1 was designed to power the transmitter. The array was composed of six cells measuring about 5 centimeters on each side, with a solar conversion efficiency of 10%.
And, look where we are now. Among the latest developments, last December the solar firm LONGi announced a new world record of 27.09% for the conversion efficiency of its latest silicon solar cell.
A near-tripling of conversion efficiency in about 60 years represents impressive progress for silicon. Now here comes perovskite to beat silicon at its own game.
Perovskite solar cells deploy synthetic versions of a naturally occurring mineral discovered in 1839 by the mineralogist Gustavus Rose, who named it after another mineralogist Lev Perovski. If you know why, drop us a note in the comment thread.
The American Chemistry Society tapped perovskite for its “Molecule of the Week” series back in 2021, explaining that perovskite is made up of the colorless compound calcium titanate (aka calcium titanium oxide0), taking on various colors depending on the introduction of iron, copper, and other impurities.
“The name ‘perovskite’ is also used broadly for compounds with the structure ABX3, in which A is a metal with oxidation state 2+; B is a metal with oxidation state 4+; and X is a nonmetal, usually oxygen, with oxidation state 2–,” ACS adds.
The application of perovskites to solar technology did not surface until 2009, when a research team in Japan is credited with introducing the first perovskite solar cell.
The team reported a conversion efficiency of 3.8% for their device. The discovery sparked a hot pursuit of further gains in conversion efficiency over the ensuing years. In the latest developments, last summer a research team based at the National University of Singapore reported 24.35% conversion efficiency for a perovskite solar cell, only to be edged out a few months later by Northwestern University, which reported 25.1% for their solar device.
Perovskite Solar Cells In Outer Space
Doing the math, that’s a much faster rate of progress than demonstrated by the silicon field, and further improvements are on the way.
Aside from tweaking conversion efficiency up, researchers have also addressed stability issues that bedeviled earlier iterations of perovskite technology. One solution is to pair perovskite and silicon material in the same solar cell, resulting in improved conversion efficiency as well as stability. Last year a tandem perovskite-silicon solar cell hit the 33.9% conversion efficiency mark, inching past the 33.7% theoretical limit of silicon alone.
NASA researchers have also begun to assess the performance of perovskites at the International Space Station, and a group of researchers based at the California Institute of Technology has included perovskites in its collection of solar cells to test for a space-to-earth wireless solar power project (see more CleanTechnica space solar coverage here).
The US company Merida Aerospace is not waiting around to see what happens next. Earlier this week the company announced that it is developing perovskite solar cells for use in low Earth orbit satellites.
Merida notes that LEO satellites typically deploy solar panels made with gallium arsenide cells, which can provide for a conversion efficiency of about 30%. The gallium arsenide formula also has a proven durability track record for space applications.
That’s all well and good, but there could be better. Gallium is rare and expensive. Perovskites could provide a more economical solution while also addressing supply chain issues.
Gallium has earned a slot on the list of critical materials kept by the US Department of Energy, which notes that “gallium is not mined directly but is produced as a byproduct of aluminum manufacturing.”
“China accounts for over 90% of the world’s gallium production and in 2023 announced severe restrictions on the export of this critical element,” the Energy Department adds.
The Perovskite Solar Cell Advantage
Another advantage of perovskite technology is its manufacture-ability. Unlike the purification and fabrication steps required of silicon, perovskites can be formulated into a solution and sprayed, printed, or painted onto a surface.
“Perovskite cells present cost-effectiveness through simplified and economical manufacturing processes. Their flexibility and versatility make the material suitable for diverse applications, from lightweight to bendable solar panels,” Merida notes.
“While gallium arsenide has been synonymous with high efficiency, ongoing research indicates that perovskite cells are rapidly closing the efficiency gap, displaying potential comparable or even higher efficiency levels,” the company adds.
As for the question of perovskite durability, Andrea Marquez, who holds the position of research engineer at Merida, evidently considers that question to be settled in terms of space applications.
“Perovskite solar cells have demonstrated remarkable resilience to high-energy radiation in space conditions, thanks to a self-healing effect,” Marquez noted in a press statement.
“Furthermore, the arrangement of perovskite crystals is influenced by space temperatures, enhancing their light absorption capabilities,” she added.
From Space To Earth
Merida already seems confident that perovskites will find their way into widespread Earth applications, ushering in a new generation of affordable solar technology.
“Perovskite technology may become a mainstream choice for powering residential, commercial, and industrial applications,” Merida notes. “This shift could redefine the solar industry landscape, moving towards a future where perovskite solar cells play a vital role in meeting the world’s growing energy demands sustainably.”
They may be getting ahead of themselves, but not by much. Last May, CleanTechnica took note of new developments in the perovskite-to-market field, including an update on a University of Oxford spinoff called Oxford PV.
Oxford has already developed an entire solar panel with a conversion efficiency of 25%, manufactured with an assist from the Fraunhofer Institute in Germany to demonstrate production-worthiness. On January 31 the company reported that it is getting ready to begin commercial deliveries at its existing factory in Germany.
That’s just one company. Other perovskite stakeholders are also in the mix so hold on to your hats.