When burned, it produces nothing more than water vapour and nitrogen, which makes up 78 per cent of Earth's atmosphere. Earlier this year Italian tyre-maker Marangoni built an ammonia-gasoline hybrid automobile, the Marangoni Toyota GT 86-R Eco-Explorer (see picture). The car can go for 178 kilometres on just one tank of ammonia. So can ammonia itself be made in a clean way?
Most ammonia is produced by heating natural gas or coal as a source of hydrogen, then forcing it to react with atmospheric nitrogen. It's highly energy-intensive, accounting for between 2 and 3 per cent of the world's energy budget and emitting over a billion tonnes of carbon each year in the process.