fact-checkedreputable news agencyproofread How Japan's big plans for a 'hydrogen society' fell flat type='text/javascript'> googletag. In the meantime, countries such as China and some European nations have moved faster on green hydrogen, which remains rare and expensive but is key to decarbonization, the Japanese Renewable Energy Institute think-tank says. hydrogen and its derivative ammonia: burning it alongside gas and coal at existing power stations, to reduce carbon emissions