Our roadways not only serve as rivers of commerce, but they can also be laboratories where currents and congestion are studied, sometimes with remarkable results.
eRoadArlanda of Rosersberg, Sweden, is one of several projects of the Swedish Transport Administration focused on the development of a method for electrifying roads. The experiments are based on conductive technology that uses an electric rail embedded in the roadway. The rail can power and recharge vehicles, and it’s being developed for the larger transport routes in the country. The ultimate goal is to create a “fossil-free transportation infrastructure by 2030-2050 to boost Sweden’s competitiveness.”
The recently opened test track is a 2-km (1.2-mile) electrified roadway that connects the Stockholm Arlanda Airport and the Rosersberg logistics site.
A PostNord truck has been modified to make continuous trips between the two points, in all seasons and weather conditions, for two years, carrying normal loads of freight. The truck has been chosen to evaluate wear and efficiency, but the technology can also support cars and buses.
The mechanical modifications for the truck and rail are impressive. A movable arm under the truck has a sensor that detects when a rail is in the roadway. When it locates the rail, the arm drops and a contact is inserted into the rail. To avoid damage to the arm, if major obstacles are detected ahead by the on-board radar, the arm lifts up out of the way. Minor obstacles are managed by the design of the arm—Smaller stones and debris are deflected, even if encountered at full speeds.
The contact is also designed to eject water from the trough it’s running in, so rain, even downpours, are cleared away. If traffic is infrequent on the roadway, this clearing of the water can be handled by adding drainage at key points for the rails. eRoadArlanda explains, “Drainage has been tested at the installation at Arlanda during winter, spring, and summer, with highly positive results.”
Frequent traffic will also clean snow and ice from the track, and snow plows can be fitted with mechanisms to clear the track as they clear the roadway. But that still might leave the problem of ice accumulating on the conductors during periods of low traffic at night. The guarded explanation for solving that problem is presented in eRoadArlanda’s online FAQ: “A patented solution for this problem was successfully tested during 2012 to 2013.” Nothing more.
But what about the risk of this live embedded rail for humans and animals? This particular problem has produced a wellthought-out, five-part solution. The high-tension conductor is buried in the road in the same way electrical wires are buried in the walls in our homes. The upper part of the rail, which you can step on, is grounded, and therefore harmless.
Second, only short sections of the conductor are receiving power and only when a vehicle is near or passing over. You could stand on the road and poke something into the track to reach the conductors, but if a vehicle is close enough to activate that section, you’re about to be run over anyway. Or as the commission puts it, “Nothing will happen until a car is very close, in which case, the risk of impact will be greater than that of an electric shock.”
If a vehicle does stop, the electricity isn’t turned on for that section. “The current is switched on only when the speed exceeds a minimum threshold.”
And finally, there are safety circuits that detect any faults, and when triggered, they will shut off a larger section of the road.
If the 2-km test track at Rosersberg is successful, the Swedish Transport Administration plans to embed the technology in 20,000 km (12,427 mi.) of Swedish roadways. The estimated cost is about SEK 80 billion (US $9.5 billion), and the agency expects to recover those costs within three years.
The Swedish experiment isn’t the only current e-roads experiment. The Siemens eHighway California demonstration last fall featured a system using overhead cables to power large trucks.
VISUAL SPEED BUMPS
A more mundane roadway problem, with an extraordinary, or at least fanciful, solution is what do you do to get drivers to slow down at intersections without a traffic light or stop sign? A traditional solution might involve embedding noisy speed bumps in the roadway. A different approach, painted onto the roadway in a small Icelandic fishing village has captured notice worldwide. It’s an optical illusion that, from one direction at least, looks like seven white granite blocks dropped right into the roadway.
All images from the Vegamalun GIH video
From the opposite direction the effect is quite different. Sail a drone over the road and from directly overhead, the seven flat pillars become seven tall walls (see video below).
Environmental Commissioner Ralf Trylla decided to try the illusion in the Icelandic town after seeing this done in New Delhi, India. He contracted Vegmalun GIH, a street-painting company, and it took a little trial and error over a few weeks to get the image to work the way they wanted.
Here’s the video that shows the illusion from various viewing angles.
You probably can expect some type of “smart roads” in your neighborhood as autonomous electric vehicles become the more reasonable alternative. There are companies also at work on embedding wireless charging pads at locations where electric-powered buses now stop along the route. The timetable for these changes, for now at least, depends entirely on the development of the vehicles that will use them.