Tandem cells at 28%

Oxford PV today announced that it has achieved 28% conversion efficiency for its perovskite/silicon tandem solar cells, improving on the company’s own previous record of 27.3% The new world record efficiency is certified by the United States National Renewable Energy Laboratory.

The record, which surpasses the current world record for a single junction silicon cell, was achieved on a laboratory scale device measuring 1cm². Oxford PV also held the previous world record for perovskite/silicon tandem cell, which it set at 27.3% back in June.

“Today’s record demonstrates the unprecedented pace of our technology development,” says Oxford PV’s Chief Technology Officer Chris Case. “We are continuing to push our perovskite-silicon solar cell technology, with a roadmap that extends beyond 30% efficiency.”

Case also notes that the cells showed good stability – which has long been a major concern when it comes to perovskites, having been subjected to 2000 hours of damp heat testing, in line with the IEC 61215 standard for PV modules.

Perovskites have seemed close to commercialization now for several years, with many leading research institutes taking an interest in their potential to provide cheap, high efficiency solar cells. However, the material’s development saw a setback earlier this month after Australia developer Greatcell Solar, which had been working with perovskites for several years, failed to secure funding for its operations and went into administration.

For Oxford PV, the outlook seems brighter, the company has not struggled to attract investments, having secured GBP 5 million ($6.3 million) in funding for a research project from the British Government, and an additional GBP 8.02 million ($10.1 million) from existing investors earlier this year.

“2018 has been a significant year for Oxford PV. Alongside the pace of our technology advancements in both efficiency and stability, our pilot line is routinely producing commercial sized tandem solar cells for validation by our development partner – a major manufacturer of silicon solar cells and modules,” says CEO Frank Averdung. “With new collaborations with key industry players strengthening our manufacturing capabilities, the foundations are in place, to move perovskite photovoltaics into commercial phase.”