Learn more about city air pollution and how Gas to Liquids (GTL) can help.
The global urban population is exploding.
For the first time over 50% of us live in cities as people migrate to urban centres to find work.
There are now 25 mega-cities with populations of 10 million or more, including Tokyo (34m), Mexico City (25m) and Delhi (20m).
More crowded cities mean more vehicles on the road - and that means more fumes, more noise and more smog.
The challenge for Shell's creative thinkers is to develop alternative fuels that produce fewer harmful emissions.
GTL Fuel is made by converting natural gas to a liquid fuel, with potentially huge benefits both in terms of lower emissions and more plentiful supply.
Trials of pure GTL Fuel in a fleet of Volkswagen Golf cars in Berlin...
...showed that the cars produced 91% less carbon monoxide emissions, 63% less hydrocarbons and 26% less particulates in their exhaust than if they'd been running on regular diesel.
Shell's new GTL plant in Qatar is the end result of three decades of investment by Shell in developing an alternative fuel that many industry experts thought would be a non-starter.
The Pearl GTL plant will produce enough GTL Fuel to power the equivalent of all the buses and taxis in up to 10 mega-cities, helping to improve urban air quality in those cities.