As reported in this article in the preceding issue [1], many Japanese companies and universities are accelerating the development of power generation devices that use renewable energy sources. Continuing from [1], the research and development activities toward innovative solar cells being conducted by the Toshiba group are introduced in this article. At present, the most widely used solar cells for power generation use crystalline silicon. However, solar cells using silicon crystals need thick glass to prevent damage from hail and the like. Partly because of that, silicon solar cells are unbendable, thick, and heavy. This causes a shortage of adequate new places to install silicon solar cells, especially in densely populated cities. If flexible, thin, and light solar cells are developed at a reasonable price, we can use lots of places to generate electric power without adding much weight. Then, various surfaces such as curved roofs, walls, and windows of houses, buildings, and other objects with low load-bearing capacity, like cars and daily commodities, can be electric power generators. Even toys and clothes are usable.
