Researchers from Kaneka Corporation, a solar energy firm based in Osaka, Japan, have created a silicon-based solar panel with a record-breaking efficiency of 26.3 per cent, later optimised to 26.6 per cent. This surpasses the previous record of 25.6 per cent, bringing the technology closer to its theoretical maximum of 29 per cent.
The team built an 180.4 square centimetre cell using a thin-film heterojunction design. Low-resistance electrodes placed at the rear maximised photon collection, while the front was coated with amorphous silicon and an anti-reflective layer to improve light absorption. The findings were published in the journal Nature Energy.
Lead author Kunta Yoshikawa noted that improving photoconversion efficiency is crucial for expanding renewable electricity. The researchers identified key loss mechanisms—resistive, optical, and recombination losses—and addressed them through the cell's architecture. However, they acknowledged that further work is needed before the cells can be assembled into commercial panels.
Currently, typical silicon solar panels achieve efficiencies in the low 20 per cent range, and homeowners may wait up to 20 years to recoup installation costs. The new panels could significantly reduce this payback period, though commercial availability remains some way off.
