Three miles of electric highway outside Frankfurt, Germany, represent a start: the eHighway (what else would it be called?) for trucks. This project of Siemens and Scania would allow modified diesel-engine trucks to switch to electric drive on heavily traveled truck routes. These trucks would raise pantographs to draw high-voltage power from overhead catenary wires, the same as you see on train lines here and abroad and the same as you see slicing up the sky view in major European cities and a few American cities for trolley cars and buses. Clean skies may come at the cost of visually congested skies.
This is only a test, for now. The electric components are out in the open, for now. This is not the dream of Halo, Qualcomm and now MIT spinoff WiTricity of inductive charging loops in roadways. Think of the Siemens-Scania project as proof of concept that relatively modest investment, billions not trillions to start, would provide a quick return on investment.
Here’s the deal, as Siemens sees it: Diesel trucks are visible signs of pollution in the eye of the public, the same public that buys the goods riding in the cargo bays of the trucks. Their noisy, badly tuned injectors let the truck billow black smoke under hard acceleration, and some people are uncomfortable with an 80,000-pound semi riding in the adjacent lane. Siemens wants to install overhead electric lines in and around major cities, at seaports, and between nearby cities.
The proposal for Germany is to install 4,000 km (2,500 miles) of contact lines (overhead wires) on the nation’s autobahns, which total 13,000 km (8,100 miles) out of 645,000 km (400,000 miles) of roadway in Germany. It wasn’t immediately clear if the 4,000 km means 2,000 km in each direction (15 percent of the autobahn electrified), or 4,000 miles of roadway (30 percent of the autobahn electrified). Still, it’s a significant amount, albeit in a country where there’s nothing like the lightly populated US heartland. In the US, a pilot might fare best in the BOS-WASH corridor.
Who’ll pay? In Siemens’ prospectus, highway tolls on trucks would fund the program. Further, Siemens says, 80 percent of heavy-duty trucks would find an economic incentive in switching to an electrified tractor (the front of the truck, not the cargo box).
The initial pilot for eHighway in Germany is between Frankfurt and Darmstadt. The first eHighway was in Sweden, launched in 2016. Scania is a Swedish truckmaker, once part of Saab, now another of Volkswagen AG’s 340 holdings. According to Siemens, the project in Germany will start out small: five trucks a day out of the 14,000 trucks using that road daily (and accounting for 10 percent of road traffic).
There’s no reason intercity buses couldn’t use the catenary wires, too.
The truck would accelerate onto the eHighway under combustion engine power. Once it’s under the catenary wires, the pantography raises and the truck switches to offboard electric power. If the truck needs to change lanes, it would switch to onboard electric power briefly while the diesel engine fires up, then return to line power when it’s back in the lane. If the truck slows down, regenerated electricity could be feed back into the grid. This follows earlier testing first at an inactive airfield, or at night with little traffic. Now they’re scaling up to those five-a-day runs. Slow and steady, like the little engine that could.