Japan's Sharp Corp., the world's biggest maker of solar cells, expects the cost of generating solar power to halve by 2010. "By the year 2010 we'll be able to halve generation costs," Katsuhiko Machida said in an interview on Thursday. The solar industry in general expects the cost of producing solar power to fall by about 5 per cent per year, on average. Machida said he expected that a shortage of solar-grade silicon, the raw material from which solar panels that harness the sun's energy are made, would ease by 2008 as silicon makers step up production to catch up with soaring demand.