Electric Roads: Sweden’s Dynamic Charging

Sweden is pioneering a shift in transportation infrastructure that could fundamentally change how heavy logistics operate. Rather than relying solely on static charging stations that require long wait times, the country has invested heavily in evaluating Electric Road Systems (ERS). This technology allows vehicles to charge dynamically while in motion. The initiative focuses on the world’s first permanent electrified road for heavy trucks, a project that highlights both the engineering potential and the economic challenges of green transit.

The Concept of Dynamic Charging

The core problem with electrifying heavy-duty trucks is the battery. To haul heavy freight over long distances, a truck typically requires a massive, heavy, and expensive battery pack. This reduces the cargo payload and increases the upfront cost of the vehicle.

Dynamic charging solves this by turning the road itself into a power source. If a truck can draw energy from the road to power its motor and top up a smaller onboard battery while driving, it no longer needs to stop for hours to recharge. Sweden’s Transport Administration, Trafikverket, identified this as a critical pathway to achieving the national goal of reducing greenhouse gas emissions from transport by 70% by 2030.

The E20 Pilot and the Permanent Road Project

The focal point of this initiative is the E20 highway. The plan designated a 21-kilometer stretch between Hallsberg and Örebro for electrification. This location was chosen specifically because it serves as a logistic hub connecting Stockholm, Gothenburg, and Malmö.

Originally slated for completion around 2025 or 2026, the project aimed to settle the debate on which ERS technology is most viable for permanent, large-scale public use. However, as of late 2023, Trafikverket had to pause the procurement process due to rising costs that exceeded the budget. This “pause” has turned into a crucial period of evaluation. The agency is now analyzing how to reduce costs and whether the timeline needs adjustment to align with broader European standards.

Despite the procurement delay, the research gathered from Sweden’s pilot programs remains the gold standard for global infrastructure planners.

Competing Technologies Evaluated

Sweden has not limited itself to one method. Through various pilot schemes like those on road 259 and in Gotland, three distinct technologies have been tested rigorously.

Catenary Systems (Overhead Lines)

This system looks similar to the setup used by trams or trains. Overhead wires run above the highway, and trucks extend a pantograph (a collapsible arm) to connect to the lines.

  • Key Players: Siemens has been a primary developer of this “eHighway” technology.
  • Pros: It is a mature, well-understood technology with high efficiency.
  • Cons: It only works for tall commercial trucks, not passenger cars. There are also concerns about the visual impact and maintenance of overhead wires in high winds.

Conductive Ground Systems (Electric Rail)

This method involves a rail embedded in the asphalt or laid on top of the road surface. A movable arm under the vehicle descends to make contact with the rail to draw power.

  • Key Players: Companies like Elonroad and Elways have tested this. Elonroad, for example, uses a rail that sits slightly above the road surface, while Elways submerges the rail into the asphalt.
  • Pros: Both cars and trucks can use it.
  • Cons: Physical wear and tear is a major factor. Snow plowing in Swedish winters presents a significant engineering challenge, as the rails must withstand heavy machinery clearing ice.

Inductive Systems (Wireless)

This is the most futuristic approach. Copper coils are buried beneath the asphalt. When a vehicle with a receiver coil drives over them, electricity is transferred magnetically, similar to a wireless phone charger.

  • Key Players: Electreon has successfully piloted this technology on the island of Gotland (Smartroad Gotland).
  • Pros: It is invisible and tamper-proof. There are no physical obstacles for snow plows or pedestrians.
  • Cons: It is generally more expensive to install and typically offers lower energy transfer efficiency compared to direct contact methods.

The Economic and Logistic Case

The evaluation of these roads goes beyond just engineering; it is a calculation of logistics. A report by the Research Institutes of Sweden (RISE) suggests that ERS could reduce the required battery size for heavy trucks by up to 50% or even 70% in optimized scenarios.

For a trucking company, this means:

  1. Lower Vehicle Cost: Smaller batteries make electric trucks cheaper to buy.
  2. Higher Revenue: Less battery weight means more capacity for paying cargo.
  3. Efficiency: No downtime for charging stops during the driver’s active shift.

However, the infrastructure cost is the hurdle. The cancellation of the E20 tender revealed that initial estimates were too low. Building an electric road is currently estimated to cost significantly more per kilometer than standard highway maintenance. The Swedish government is now looking at how to balance these infrastructure costs against the savings for private haulage companies.

Future Outlook and EU Expansion

Sweden is not working in isolation. The ultimate success of the E20 project and subsequent roads depends on standardization. A truck driving from Germany to Sweden needs to use the same charging system in both countries.

France and Germany are also running ERS pilots, heavily influencing the final decision on which technology will become the European standard. While the timeline for the “permanent” E20 road has shifted, the data from Sweden’s evaluation proves that dynamic charging works technically. The challenge now is purely economic: bringing the cost of the road down to match the savings on the vehicle.

Frequently Asked Questions

Is the electric road safe for pedestrians? Yes. In conductive rail systems, the rail is only electrified in short segments directly underneath the vehicle moving over it. If a person walks on the rail, it is not active. Inductive systems are buried underground and pose no shock hazard.

How do drivers pay for the electricity? The systems are designed with automatic identification. When the vehicle connects to the rail or overhead line, the system recognizes the truck’s ID and bills the operator for the kilowatt-hours consumed, similar to a toll road.

Does it work in the snow? This is a primary focus of the Swedish tests. Overhead lines are generally unaffected by snow on the ground. Rail systems like Elonroad’s have been designed with slanted edges to help snow plows clear them, and the heat from the electricity can help melt thin layers of ice.

Will all roads be electrified? No. The plan is only to electrify high-traffic “triangle” routes between major logistics hubs. Trucks would use battery power for the “last mile” delivery on smaller roads and recharge via the highway on long hauls.