Chinese scientists have tested a photovoltaic system based on perovskite solar cells in open sea conditions at a depth of 10 meters for the first time in the world.
Sea-news.az reports citing Chinese media, that the technology was developed to efficiently utilize the limited solar spectrum penetrating underwater.
The study by scientists from Yunnan University was published in the journal Joule. The developed solar cells are adapted to blue-green light with a wavelength of 400–600 nanometers, which predominates at depths of 5–10 meters. This is because red light is absorbed more rapidly by water.
The system is based on lead halide perovskite. Polyhexamethylene guanidine hydrochloride was added to the material to enhance its electron-retaining capability. Under laboratory conditions, energy conversion efficiency reached approximately 35 percent.
The system was subsequently tested in the South China Sea near Weizhou Island. Using remotely operated robots, solar cells with an area of 115 square centimeters were deployed at depths of 2, 6, and 10 meters.
During testing, the cells generated 1,416, 752, and 324 milliwatt-hours of electricity, respectively. In all cases, the generated energy was sufficient to charge lithium-ion batteries and power an LED panel.
According to the researchers, the new technology could be used in the future to power underwater communication systems, video surveillance and broadcasting equipment, acoustic monitoring systems, and other autonomous underwater devices.
