Automotive

Sweden's new electric highway works like a scaled-up slot car track

Sweden's new electric highway ...
The Swedish project eRoadArlanda powers electric vehicles through a slot car-like track embedded in the road
The Swedish project eRoadArlanda powers electric vehicles through a slot car-like track embedded in the road
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The Swedish project eRoadArlanda powers electric vehicles through a slot car-like track embedded in the road
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The Swedish project eRoadArlanda powers electric vehicles through a slot car-like track embedded in the road
To prevent shocks, the electrified eRoadArlanda rails are earthed at the surface, with the conductor buried deep underneath
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To prevent shocks, the electrified eRoadArlanda rails are earthed at the surface, with the conductor buried deep underneath
The eRoadArlanda rails being laid in a stretch of public road
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The eRoadArlanda rails being laid in a stretch of public road
In the eRoadArlanda project, electricity is fed from parallel tracks in the road into a vehicle through a retractable arm attached to the bottom of the car
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In the eRoadArlanda project, electricity is fed from parallel tracks in the road into a vehicle through a retractable arm attached to the bottom of the car
Officials cut the ribbon at the inauguration of the public section of eRoadArlanda electrified road
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Officials cut the ribbon at the inauguration of the public section of eRoadArlanda electrified road
The eRoadArlanda rails being laid in a stretch of public road
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The eRoadArlanda rails being laid in a stretch of public road
The first vehicle to use the new eRoadArlanda section will be a truck run by PostNord
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The first vehicle to use the new eRoadArlanda section will be a truck run by PostNord
The eRoadArlanda rails being laid in a stretch of public road
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The eRoadArlanda rails being laid in a stretch of public road

In a move that will probably delight anyone who raced slot cars as a kid (or an adult), the Swedish Transport Administration has just opened a 2-km (1.2-mi) stretch of electrified road that works the same way. The project, dubbed eRoadArlanda, involves embedding electric rails into the road surface to power electric vehicles through a contact arm hanging down from under the car.

If electric vehicles are ever going to become mainstream, the infrastructure around them needs to be as convenient for drivers as possible. Charging stations are getting more common and more advanced, and we've seen other systems proposed that would top up cars on the go, like wireless charging lanes or Siemens' eHighways that use overhead cables.

In the eRoadArlanda project, electricity from two parallel tracks in the road is fed into a vehicle through an arm attached to the underside of the car. That might sound restrictive, but the arm is retractable, and hooked up to sensors that tell it to only extend down when it's above the rails. If the car needs to overtake or turn off the road, the arm folds back up out of the way and the vehicle draws power from its battery.

Electrifying the road might sound like a dangerous idea, but the tech has been designed with a few measures in place to protect humans and animals that might walk across it. The track at the surface is earthed to prevent shocks, with the conductor itself buried deeper down – and even then only short sections are powered at a time, as vehicles pass over them. To get zapped, you'd need to be on your hands and knees jamming a fork between the rails, in which case the more immediate danger would be the car speeding towards you.

To prevent shocks, the electrified eRoadArlanda rails are earthed at the surface, with the conductor buried deep underneath
To prevent shocks, the electrified eRoadArlanda rails are earthed at the surface, with the conductor buried deep underneath

Rain reportedly won't pose a problem either. Drainage systems are in place along the track, and the contact arm has been designed to push water out of the way – as well as gravel, rocks and other small obstacles. The gap between the rails is also too small to cause a problem for motorbike and bicycle wheels.

After a few years of testing on an enclosed track, the project is now moving onto public roads. The 2-km test rail runs between the cargo terminal at Stockholm Arlanda airport and the Rosersberg logistics site, and will be used by a modified PostNord truck. If that goes well, the Swedish Transport Administration is planning a larger rollout across the country's highways. According to the eRoadArlanda group, electrifying 20,000 km (12,427 mi) of Sweden's roadways would cost about SEK80 billion (US$9.5 billion), but the cost would be recouped within three years.

The first vehicle to use the new eRoadArlanda section will be a truck run by PostNord
The first vehicle to use the new eRoadArlanda section will be a truck run by PostNord

The ultimate goal is for the rails to complement the wider electric vehicle infrastructure. Only highways and arterials need to be electrified in this way, while the vehicles can run on battery power on smaller streets and recharged at home or other stations if needed. Rather than trying to combat range anxiety by developing bigger batteries, the project is reducing the length of the journeys between power sources to a distance that current electric cars can already manage.

The group describes the project in the video below.

Source: eRoadArlanda

eRoadArlanda - globally unique electrified road enables fossil-free road transport

11 comments
MartinVoelker
It's interesting to see the claim that the high looking cost of "US$9.5 billion...would be recouped within three years". Whether or not that is true it's rare to find these cost vs amortisation figures stated. I applaud it because any big figure looks scary unless you know its proportion. I'm also referring to Paul Hawken's project drawdown.org which looks for climate solutions, ranks them, and provides a cost vs. savings analysis.
guzmanchinky
That's a lot of power to put where (if some system fails) someone stepping on it could be electrocuted. Seems overly complex to me from an infrastructure standpoint, considering the any-day-now advances in doubling battery energy density and quick charging.
bwana4swahili
Looks like a major step backward in technology to the days of streetcars with overhead lines. Let's look forward...
VincentWolf
It will never work unless the system is wireless charging. Slots are good for slot cars nothing more.
DaveWesely
The more I think about this, the more advantages it has over charging stations. This would provide a source of revenue for the highway system much like the gas tax does for ICE cars. It would provide unlimited range for electric cars on our interstate system and main arterials where most of the long-distance travel is done. Electric cars wouldn't need huge batteries for extended range so they'd be cheaper. Only the main arterials would need a rail. On a two, three, or four lane highway, only one lane would need to be electrified. Rush hour traffic would not increase the load on the electrical system. Most of those vehicles would not use the rail since they would be short distance commuters running on batteries. Long distance travelers would take a continuous charge, instead of short bursts of charge at charging stations - creating a load leveling effect on electric infrastructure. This could be utilized on long highway inclines to transfer energy from vehicles going down the hill to vehicles going up the hill.
Richard Treadgold
I like the idea for its simplicity, although as VincentWolf remarks, wireless charging would be best. However, too many things could damage the rails, including the ingress of foreign bodies, especially of a shape that could jam in the groove, block the channel and wreck the car's contact arm, or damaging fluids. At motorway speeds the velocities and inertial forces on the components would be enormous. Thorough testing should identify these problems. But there's a more significant problem. Clearly the only body capable of approving and paying for this technology to become widespread is some regional or national government, yet in the history of industrial development, the only initiatives to succeed were private ones, driven by entrepreneurs finely attuned to the needs of their putative clients. Government-driven development always fails to meet market needs. This poses a significant hurdle to uptake of this technology unless the investors produce truly astounding test segments of road, prove it all works and, above all, make it affordable. In the meantime, the climate is cooling and nobody can prove that our emissions cause significant warming. I note that the Royal Society of New Zealand has as good as <a href="https://tinyurl.com/y7uqtx34">admitted it cannot find evidence</a>.
Nik
'' The gap between the rails is also too small to cause a problem for motorbike and bicycle wheels.'' NOT TRUE! In France many of the older concrete autoroutes, had 'rainage' grooves cut into the surface. These grooves were approx 6mm/1/4inch wide, but they caused motorcycles significant problems, as the rounded profile of tires reacted strongly to the grooves, causing the machine to yaw wildly. Old railway tracks were also a problem, especially if wet, as again the rounded tire profile tended to lock into them, unless they were approaches at close to 90 degrees. As for carbon emissions, here are some simple scientific facts; FACT: Life on Earth is carbon based, FACT: The primary source of that carbon is Atmospheric CO2. (ACO2) FACT: The primary Source for that ACO2, are the oceans. FACT: The primary source of that CO2 is from undersea volcanoes. FACT: When the oceans cool, they release less CO2. FACT: The present average global temperature is the lowest it has been since the Permian extinction 270 million years ago. FACT:The present level of atmospheric CO2 and throughout this inter ice age at around 400 ppm, is the lowest it has been since the Permian Extinction 270 Million years ago. FACT: The world would benefit greatly from an increase in ACO2, to 1000 ppm. FACT: If ACO2 falls below 150 ppm, all major land surface plant life will start to die, from ACO2 starvation, except, grasses, and similar. FACT: That death will be closely followed by all land surface animal life dependent upon it. FACT: Humans will probably be one of the first to start to die. FACT: Reducing ACO2 from its present impoverished level, will endanger the whole of land animal life on Earth. FACT: From the above, it can be seen that the Anthropogenic Global Warming claims are a total and dangerous scam, promoted purely for the benefit of $$trillions of carbon tax!
Jim B
Or just produce ammonia cheaply using high temperature 4th gen nuclear (molten salt reactors) and burn that in ICEs producing only Nitrogen and Water. No need to expensively update most of the road network. Ammonia is also a solution for planes and ships.
Fairly Reasoner
OK. Now come up with something that'll work.
Craig Jennings
I suggested something similar when we had a stretch of rail electrified in my city. Trains use tracks. So use an electrified track 3rd rail that only became active when the train was on it using something that trains are..... HEAVY. So of course now we have ugly overhead power which is damaged on the regular and a pain in the behind. :D