Overhead power lines have been used to power streetcars and trams since the 1870s. Turns out that technology may be a way to reduce carbon emissions, reduce dependence on fossil fuels and increase energy efficiency if it can be applied to powering today's hybrid electric trucks. Will it work? Council Associate Partner Siemens is betting it will. The story below provides details on a test project that's expected to answer the question. While the system may not be suitable for every location, city leaders in areas with heavy truck traffic will want to keep an eye on how this project progresses. —Doug Peeples
Siemens has been involved in electric-powered freight transport for some time. Now, the company is testing a catenary system very much like the overhead power lines used to power streetcars and trams. Hybrid diesel trucks travel on a 1.25-mile section of highway (referred to as an eHighway) near Stockholm, Sweden connected to free-hanging overhead power cables. The test is part of the country's climate strategy which includes achieving a transit network free of fossil fuels by 2030.
How it works
The trucks can travel at normal highway speeds because the mechanism that connects the trucks to the overhead power supply—called a pantograph—can maintain contact with the power cables as the trucks change positions within their lanes. If a truck leaves the overhead power grid or the driver needs to take evasive action, the pantograph retracts and the truck relies on its diesel engine. While connected to the overhead power lines, the truck relies on electric power which also charges its battery.
Sweden is an appropriate choice for the test. It relies heavily on trucks for freight transport, which also generate about a third of the country's carbon dioxide emissions. Anders Berndtsson is chief strategist for the Swedish Transport Administration. Quoted in a PC Magazine article, he said "By far the greatest part of the goods transported in Sweden goes on the road, but only a limited port of the goods can be moved to other traffic types. That is why we must free the trucks from their dependence on fossil fuels, so that they can be used also in the future. Electric roads offer this possibility and are an excellent complement to the transport system."
Siemens, which is working with Swedish commercial vehicle maker Scania on the project, says the catenary system could not only significantly reduce pollution, but also cut fuel consumption in half.
Siemens also is working with Volvo on an e-Highway demonstration in California to test how well a variety of truck configurations work within an eHighway system. That project is being conducted in the Los Angeles and Long Beach area and will continue through 2017.
For more on smart transportation...
Transportation, like energy networks, is a key contributor to a smart, sustainable, livable city. The Transportation chapter of the Smart Cities Readiness Guide provides guidance and insights on planning and developing a smart transportation network capable of mitigating many of today's problems—from traffic congestion to carbon emissions.
Doug Peeples is a Portland, Oregon-based writer specializing in technology and energy. Follow @smartccouncil on Twitter.