Hydrogen cars - Japan's water-powered revolution?
Japanese car manufacturers have set their sights on being the lead exporter of hydrogen-powered cars.
Toyota announced earlier this year that it was willing to share its thousands of patents with other manufacturers and has recently delivered the first of its new Mirai fuel cell cars to owners in Japan, the USA, Denmark, Germany and the UK.
Meanwhile, Honda has designed hydrogen stations which can generate the gas as well as store it.
BBC Click's Dan Simmons reports.
More at BBC.com/Click and @BBCClick.