The Future is Here: Catenary-less Power for Light Rail
Because it is contact-less, Primove is able to operate in all climates. Snow, ice, sand and salt on the rails do not impact its ability to run.
However, this advantage causes a unique set of challenges. EMC/EMI emissions can cause safety problems with electronic devices such as pacemakers. Bombardier has engineered the system to meet all EMC codes and standards.
“Primove presents no health or safety hazard to the passengers or to the persons near the system,” asserts Bombardier’s Maryanne Roberts. “It does not cause any interference with systems or equipment.”
Bombardier installed the Primove system in Augsburg, Germany, last year. The experiment is along a .8km section of track leading into the fairground and is meant to test and demonstrate the system under real working conditions.
Kinkisharyo e-Brid System
Unlike other catenary-free systems, Kinkisharyo’s solution employs lithium-ion batteries. There are therefore no other costs associated with the system. There are no cables or conduits to lay. E-Brid carries the power onboard in its battery packs.
Trains can run for up to five miles on the batteries before needing to be recharged, making the system best for short-run trams with frequent stops. However, hybrid technology allows the batteries to recharge from catenary sources when the train is running on traditional power. Thus, trams equipped with e-Brid can run on battery in the city, then switch to catenary power out in the suburbs or rural areas where overhead lines are still used, taking advantage of this power source to recharge the batteries.
The downside of a battery-powered system is the threat of the power cells running out of charge. That could cause HVAC systems to fail, leading to passenger discomfort. Kinkisharyo believes it has solved this issue with the life of its Lithium-ion batteries. With a five-mile range and the ability to recharge from traditional catenary lines, trains employing the e-Brid system should not suffer any loss to HVAC capabilities.
“Battery technology has now progressed to a point where energy storage capacity makes catenary-less urban rail operation a reality without compromise in service performance,” Hombach says. “Passengers will have air conditioning and heating, and enjoy the same level of speed and acceleration expected from catenary-powered systems.”
Catenary-less Practicality
While a system that doesn’t employ overhead lines is ideal for a number of reasons, the real question lies in the practicality of how easily they can be installed. Each of the four manufacturers with catenary-less systems believes it has made this a non-issue.
In-ground systems like TramWave, APS and Primove all require the laying of power conduits along track lines, but the cost of doing so is not prohibitive. Moreover, the savings of the new system make it cost-efficient in the long-term. The conduit modules are prefabricated and easily installed.
“Installation is very simple thanks to prefabricated modules that are installed in and along the track, and electric connections are done over connectors,” notes Roberts of Bombardier’s system. “In case of retrofit on existing installation, installation of the components are also very simple . . .”
Likewise, Ansaldo STS, Alstom, and Bombardier have made the power collector units for their systems easily adaptable to existing trams of all varieties, and they are usable by rubber-wheeled vehicles as well, making switching to a catenary-less system easy despite whatever system is in place currently.
Kinkisharyo boasts that using the e-Brid system is even easier, since it only requires the installation of the battery system onboard existing vehicles. Without having to lay a new power system, there is less to spend and do to move to catenary-less propulsion.
“There is no need for the other types of proprietary and expensive wayside installations that often render (an) entire transit operation reliant on one company’s technology,” Hombach says.
