A professor at Tohoku University in Japan claims to have developed a photovoltaic cell that transmits about 80% of visible light. The photovoltaic cell is so transparent that it is almost invisible to the naked eye, and it won't block the view when attached to a window or car glass. The power generation capacity is sufficient to drive small sensors etc. The goal is to be practical within 5 years.
A metal compound called "transition metal chalcogenide (Dichalcogenide)" is used for the power generation layer. Less than 1 nanometer thick, it is very thin, transparent, and has semiconducting properties that convert light energy into electricity.
The electrodes use transparent metals that replace nickel and palladium with indium and tin, enabling photovoltaic cells that transmit about 80 percent of visible light. Although there have been examples of transparent photovoltaic cells developed before, most of them are "semi-transparent" cells with visible light transmittance of only about 60%.
The photovoltaic cells developed this time have improved how and how the layers overlap and can generate about 420 petawatts (one part per trillion) of electricity in an area of one square centimeter. It is said that about 100 picowatts can drive sensors that consume less power, so the power generation capacity of the photovoltaic cell has reached a practical level.
