What happens to flights if the world runs out of oil? Well, obviously they will be grounded. To be more specific, is it possible, if the war in Iran does not resolve and the strait of Hormuz remains blocked, that airlines will simply run out of aviation fuel?

It’s not a question anyone has had to ask before. Air travel has hit some hurdles this century that nobody could have seen coming – Covid, of course, but also the Icelandic volcano in 2010, which closed much of European airspace for eight days, cost an estimated €3.75bn (£3.2bn) and caused untold supply chain chaos. There have been problems contained within a country or region – the Heathrow substation outage and the Iberian energy crisis, both last year, both closing airports – but since air travel began, it has never been globally impeded by a fuel shortage.

So how likely is it? What would it look like, to consumers, to governments, to economies? And could there be a silver lining, in the form of fewer carbon emissions in the short-term, and in the long-term, the ushering in of post-fossil-fuel air travel?

OK, to deflate some of the suspense, literally running out is not a thing. While 41% of European aviation fuel goes through the strait of Hormuz, and market analysts Kpler showed global shipments of jet fuel and kerosene fell below 2.3m tonnes last week, which is the lowest level on record, Richard Green, professor of sustainable energy business at Imperial College London, lays out the numbers. “The world uses about 100m barrels of oil a day, most of it from oilfields, a bit comes out alongside gas. In normal circumstances, about 15m barrels a day would go through Hormuz. Some of that can instead go through pipelines. The UAE has got coastline on the Indian Ocean, Saudi Arabia has coastline on the Red Sea, there’s a bit of production increase in other countries, the world was producing more than it was using last year … so the real drop is five or 10 out of 100.”