Japanese team breaks solar cell efficiency record

Researchers at the University of Tokyo have set a new efficiency record for solar cells. The team used a perovskite-silicon tandem cell to reach 26.2% conversion efficiency, surpassing the previous best of 25.7% set by a Chinese team in 2022. The achievement was published in the journal Nature Energy on Monday. This marks the first time a Japanese institution has led such a record in over a decade.

The material used is a hybrid of perovskite and crystalline silicon, combining the high efficiency of perovskite with the stability of silicon. Perovskite layers absorb blue and green light more effectively, while silicon handles red and infrared wavelengths. The researchers improved the cell’s interface layers to reduce energy loss during charge transfer. This reduces the gap between lab results and commercial viability.

Tandem solar cells stack two light-absorbing layers to capture more of the solar spectrum. Traditional silicon cells max out around 22% efficiency in real-world conditions. Earlier this year, a Swiss team reached 31.3% in lab tests using a different perovskite-silicon combination. The Japanese team’s focus was on durability, testing the cell under accelerated aging conditions for 1,000 hours with minimal performance drop.

The next step involves scaling up production. The university has partnered with industry leaders to test manufacturing processes. If successful, this could lead to commercial panels within five years. The team emphasizes cost control, aiming to keep the new cells within 10% of standard silicon panel prices. Global solar capacity reached 1.6 terawatts in 2023, according to the International Renewable Energy Agency.

Source: tu.no