Overhead contact line hybrid vehicle test setup scheduled for demolition

Electrically Operated Overhead Hybrid Trucks: A Promising Solution for Long-Haul Transport

The "eWayBW" project, initiated by the Baden-Württemberg Ministry of Transport, is exploring the potential of overhead hybrid trucks for long-haul goods transport. This innovative approach combines electric power from overhead lines with on-board hybrid powertrains, offering significant efficiency and emissions advantages over conventional diesel trucks.

The "eWayBW" Project: A Collaborative Effort

The Federal Ministry of the Environment contributed the largest share of costs, around 26.4 million euros, with the state contributing around 1.6 million euros. Other alternative drive forms such as a pure electric truck and a truck powered by biofuel were also examined as part of the project.

The test track for overhead hybrid trucks on the B 462 in Kuppenheim (Rastatt district) cost around 28 million euros and is electrified in each direction of travel with two sections, totaling around 3.5 kilometers each. The truck manufacturer Daimler Truck from Leinfelden-Echterdingen participated with a battery-electric series-near E-Lkw prototype.

Advantages of Overhead Hybrid Trucks

Energy Efficiency and Emissions

Electric drive systems convert energy into movement with much higher efficiency than internal combustion engines. A diesel truck uses roughly 3.37 times the energy per mile that an electric truck does. Hybrid trucks that combine electric and diesel power reduce greenhouse gas emissions and nitrogen oxides (NOx) by about 65% compared to diesel-only trucks. Overhead trolley-assist further improves efficiency by supplying electric power directly during high-demand phases, reducing battery drain and fuel use.

Operational Performance

Electric mining trucks with overhead trolley systems can operate continuously through shifts and handle up to 20% more haul loads, thanks to electric power and regenerative braking that recaptures energy downhill. This suggests similar benefits could translate to long-haul freight trucks using overhead electrification.

Challenges for Broader Use

Infrastructure Requirements

Overhead lines for trolley-assist hybrid trucks demand substantial infrastructure investment along highways and freight corridors. Building and maintaining this electrified roadside network widely is costly and logistically complex.

Battery Costs and Range Limits

Battery packs currently add significant upfront cost and weight. While costs have declined 97% over recent decades, improving cost-effectiveness remains a hurdle. Limited battery-specific energy reduces driving range, especially important for Class 8 long-haul trucks where frequent stops for charging are impractical.

Use Case Limitations

Hybrid trucks show best efficiency gains in stop-and-go or urban delivery settings due to regenerative braking. For long-haul operators running steady highway speeds, the benefits are less pronounced, making the economic case less clear.

Coordination and Management

Effective use of electric and hybrid fleets requires advanced fleet and energy management systems with real-time monitoring and AI-enabled route and charge optimization to minimize downtime and maximize efficiency.

Policy and Market Development

The transition demands supportive policies, incentives, and coordinated efforts among utilities, manufacturers, fleets, and communities to address cost, infrastructure, and equity issues.

While electrically operated overhead hybrid trucks represent a technically viable and environmentally beneficial alternative to conventional diesel trucks for long-haul transport, infrastructure costs, battery limitations, and operational constraints for long uninterrupted runs remain significant barriers to broader deployment at present. Ongoing technology improvements and infrastructure development combined with supportive policy frameworks will be critical to unlocking their widespread use.

Unfortunately, as of Tuesday, the "eWayBW" project is being dismantled, and no information about the specific purpose or outcome of the project has been provided. The federal road chosen for the pilot project is used for transporting around 510,000 tons of paper annually from three paper manufacturers in Obertsrot to a logistics center in Kuppenheim.

Overhead contact line hybrid vehicle test setup scheduled for demolition