Nav: Home

Dual-layer solar cell developed at UCLA sets record for efficiently generating power

August 30, 2018

Materials scientists from the UCLA Samueli School of Engineering have developed a highly efficient thin-film solar cell that generates more energy from sunlight than typical solar panels, thanks to its double-layer design.

The device is made by spraying a thin layer of perovskite -- an inexpensive compound of lead and iodine that has been shown to be very efficient at capturing energy from sunlight -- onto a commercially available solar cell. The solar cell that forms the bottom layer of the device is made of a compound of copper, indium, gallium and selenide, or CIGS.

The team's new cell converts 22.4 percent of the incoming energy from the sun, a record in power conversion efficiency for a perovskite-CIGS tandem solar cell. The performance was confirmed in independent tests at the U.S. Department of Energy's National Renewable Energy Laboratory. (The previous record, set in 2015 by a group at IBM's Thomas J. Watson Research Center, was 10.9 percent.) The UCLA device's efficiency rate is similar to that of the poly-silicon solar cells that currently dominate the photovoltaics market.

The research, which was published today in Science, was led by Yang Yang, UCLA's Carol and Lawrence E. Tannas Jr. Professor of Materials Science.

"With our tandem solar cell design, we're drawing energy from two distinct parts of the solar spectrum over the same device area," Yang said. "This increases the amount of energy generated from sunlight compared to the CIGS layer alone."

Yang added that the technique of spraying on a layer of perovskite could be easily and inexpensively incorporated into existing solar-cell manufacturing processes.

The cell's CIGS base layer, which is about 2 microns (or two-thousandths of a millimeter) thick, absorbs sunlight and generates energy at a rate of 18.7 percent efficiency on its own, but adding the 1 micron-thick perovskite layer improves its efficiency -- much like how adding a turbocharger to a car engine can improve its performance. The two layers are joined by a nanoscale interface that the UCLA researchers designed; the interface helps give the device higher voltage, which increases the amount of power it can export.

And the entire assembly sits on a glass substrate that's about 2 millimeters thick.

"Our technology boosted the existing CIGS solar cell performance by nearly 20 percent from its original performance," Yang said. "That means a 20 percent reduction in energy costs."

He added that devices using the two-layer design could eventually approach 30 percent power conversion efficiency. That will be the research group's next goal.
-end-
The study's lead authors are Qifeng Han, a visiting research associate in Yang's laboratory, and Yao-Tsung Hsieh and Lei Meng, who both recently earned their doctorates at UCLA. The study's other authors are members of Yang's research group and researchers from Solar Frontier Corp.'s Atsugi Research Center in Japan.

The research was supported by the National Science Foundation and the Air Force Office of Scientific Research. Yang and his research group have been working on tandem solar cells for several years and their accomplishments include developing transparent tandem solar cells that could be used in windows.

UCLA Samueli School of Engineering

Related Solar Cell Articles:

Windows will soon generate electricity, following solar cell breakthrough
Semi-transparent solar cells that can be incorporated into window glass are a 'game-changer' that could transform architecture, urban planning and electricity generation, Australian scientists say in a paper in Nano Energy.
Ultrathin organic solar cell is both efficient and durable
Scientists have succeeded in creating an ultrathin organic solar cell that is both highly efficient and durable.
Layered solar cell technology boosts efficiency, affordability
Researchers from CU Boulder have created a low-cost solar cell with one of the highest power-conversion efficiencies to date, by layering cells and using a unique combination of elements.
Anti-solar cells: A photovoltaic cell that works at night
What if solar cells worked at night? That's no joke, according to Jeremy Munday, professor in the Department of Electrical and Computer Engineering at UC Davis.
Promising discovery could lead to a better, cheaper solar cell
McGill University researchers have gained tantalizing new insights into the properties of perovskites, one of the world's most promising materials in the quest to produce a more efficient, robust and cheaper solar cell.
Biological material boosts solar cell performance
Next-generation solar cells that mimic photosynthesis with biological material may give new meaning to the term 'green technology.' Adding the protein bacteriorhodopsin (bR) to perovskite solar cells boosted the efficiency of the devices in a series of laboratory tests, according to an international team of researchers.
Experiments show dramatic increase in solar cell output
Researchers at MIT and Princeton have found a way to increase the output of silicon solar cells by allowing a single photon to release two electrons in the silicon.
Winds of change...Solar variability weakens the Walker cell
An international team of researchers has found robust evidence for signatures of the 11-year sunspot cycle in the tropical Pacific.
Improving solar cell efficiency with a bucket of water
Beth Parks has devised an astonishingly simple way to overcome a limitation of solar cells -- a bucket of water.
Solar panels for yeast cell biofactories
In a study in Science, a multidisciplinary team led by Core Faculty member Neel Joshi and Postdoctoral Fellows Junling Guo and Miguel Suástegui at Harvard's Wyss Institute for Biologically Inspired Engineering and John A.
More Solar Cell News and Solar Cell Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Listen Again: Reinvention
Change is hard, but it's also an opportunity to discover and reimagine what you thought you knew. From our economy, to music, to even ourselves–this hour TED speakers explore the power of reinvention. Guests include OK Go lead singer Damian Kulash Jr., former college gymnastics coach Valorie Kondos Field, Stockton Mayor Michael Tubbs, and entrepreneur Nick Hanauer.
Now Playing: Science for the People

#562 Superbug to Bedside
By now we're all good and scared about antibiotic resistance, one of the many things coming to get us all. But there's good news, sort of. News antibiotics are coming out! How do they get tested? What does that kind of a trial look like and how does it happen? Host Bethany Brookeshire talks with Matt McCarthy, author of "Superbugs: The Race to Stop an Epidemic", about the ins and outs of testing a new antibiotic in the hospital.
Now Playing: Radiolab

Dispatch 6: Strange Times
Covid has disrupted the most basic routines of our days and nights. But in the middle of a conversation about how to fight the virus, we find a place impervious to the stalled plans and frenetic demands of the outside world. It's a very different kind of front line, where urgent work means moving slow, and time is marked out in tiny pre-planned steps. Then, on a walk through the woods, we consider how the tempo of our lives affects our minds and discover how the beats of biology shape our bodies. This episode was produced with help from Molly Webster and Tracie Hunte. Support Radiolab today at Radiolab.org/donate.