SO-LAR SO GOOD: Scientists Break Record Converting Sun’s Radiation Into Electricity

Scientists have developed a groundbreaking solar cell that can convert almost a third of the sun’s radiation into electricity.

Image shows the perovskite/silicon tandem solar cell, undated photo. The active bluish area in the middle of the wafer, which is enclosed by the metallic, silvery electrode can be seen. (Johannes Beckedahl, Lea Zimmerman, HZB/Newsflash)

The new silicon bottom and perovskite top tandem cell was created by researchers from Helmholtz Zentrum Berlin (HZB) in Germany.

It reportedly broke the world record by transforming 32.5 per cent of the incident solar radiation into electrical energy.

The previous holder had been the Swiss Ecole Polytechnique Federale de Lausanne (EPFL) which reached 31.3 per cent earlier this year.

European Solar Test Installation (ESTI) experts measured and confirmed the value of the cell, after which it was included in the National Renewable Energy Laboratory’s (NREL) chart of solar cell technologies.

The NREL which specialises in the research and development of renewable energy is headquartered in the city of Golden, Colorado State, USA.

HZB researcher Steve Albrecht told Newsflash in a statement: “This is a really big leap forward that we didn’t foresee a few months ago.

“All the teams involved at HZB, especially the PV Competence Center (PVComB) and the HySPRINT Innovation lab teams have worked together successfully and with passion.”

For the purpose of the study, lead authors and postdocs Dr Silvia Mariotti and Dr Eike Koehnen developed an interface modification to reduce charge carrier recombination losses.

Image shows the structure of the tandem solar cell with a bottom cell made of silicon and a top cell made of perovskite, undated photo. While the top cell can utilize the blue light components, the bottom cell converts the red and near-infrared components of the spectrum. Various thin layers contribute to optimal utilization of the light and minimization of electrical losses. (Eike Koehnen, HZB/Newsflash)

They then applied detailed analysis to understand the specific properties of the interface modification and successfully implemented the developments in tandem solar cells.

Student Lea Zimmermann then combined them with further optical improvements, which finally resulted in a new record.

Albrecht said: “We are very excited about the new value as it shows that the perovskite/silicon tandem technology is highly promising for contributing to a sustainable energy supply. “

HZB’s scientific director Bernd Rech added: “At 32.5 percent, the solar cell efficiency of the HZB tandems is now in ranges previously only achieved by expensive III/V semiconductors.

“The NREL graph clearly shows how spectacular the last two increases from EPFL and HZB really are.”

The breakthrough is extremely relevant for the research centre which collaborates with globally active mechanical engineering company Meyer Burger, located in Thun, Switzerland.

Image shows efficiencies of the silicon/perovskite tandem cells, undated photo. The latest world record by the Helmholtz Zentrum Berlin (HZB) team in Germany, is a big step forward. (NREL/Newsflash)

The Swiss company’s objective is to produce solar cells with over 30 per cent efficiency on an industrial scale, and thus outrun its Chinese competitors whose products reach around 23 per cent efficiency in commercial use and about 25-26 per cent in the lab.

Meyer Burger is reportedly one of the few European companies attempting to revive the manufacturing sector on the continent, after cheap Chinese production nearly killed it about a decade ago.