Elisabeth Behrmann:

Although driverless cars grab headlines, it may take decades before truly autonomous vehicles rule the road. In the meantime, semiautomated convoys can help manufacturers hone the technology while cutting emissions and fuel consumption, says Anders Kellström, who managed Volvo’s test run to Rotterdam. “Platooning is one of the first steps toward automated driving,” he says. “The technology is mature.”
 Drivers will still be needed—by law they’ll have to keep their hands on the wheel. But letting the rig do some of the work will result in less passing, quicker braking, and fuel savings of about 10 percent for the following trucks and a smaller gain for the lead vehicle, according to Daimler. And it will help reduce congestion. When a human is at the wheel, a truck in some countries must maintain a distance of about half a football field from the vehicle in front of it to stop safely in an emergency. With automation, that distance shrinks to about 50 feet. “Traffic on the whole will become calmer,” says Andreas Renschler, who heads the Scania and MAN truck brands for Volkswagen.