Wireless supercapacitor trams could bring multiple benefits to the operation of Melbourne’s inner-city transport network.
Leading figures in both the rail industry and the sustainability and efficiency sector have recommended that Melbourne gradually dismantle the overhead wires that supply the city's 250-kilometre tram system with power.
Bryan Nye, chief executive of the Australasian Railway Association, said the development of new power technology has made it possible to remove the overhead lines of urban tram systems, as already amply demonstrated by numerous cities around the world.
According to Nye, the removal of overhead power lines from tram system is an inevitable trend in global transportation which Melbourne would be wise to follow.
"I think eventually, within 10 years, you won't find anywhere that's got overhead wires," he said. "If you wanted to modernise the network in Melbourne you certainly wouldn't be doing it with wires, you'd look at some of the alternative technologies."
Nye's remarks follow a similar call from Matthew Wright, executive director of Zero Emissions Australia, for Melbourne's iconic tram system to go wireless.
While multiple technologies exist for building wireless tram networks, both Nye and Wright advocate the adoption of new supercapacitors as the most advantageous and cost-effective approach.
Since the turn of the century, increases in the power density of supercapacitors have revolutionised the operation and design of modern tram systems, enabling them to dispense with overhead power lines completely.
The latest supercapacitors developed in China are as small as milk cartons and can be readily installed beneath the floors or in the roofs of trams for rapid recharging at stops.
Wright points out that wireless supercapacitor-based tram systems provide multiple benefits during both the construction and operating phases.
The systems are far easier to build and incorporate into the often challenging terrain of urban environments by obviating the need for intrusive and unwieldy overhead infrastructure.
The absence of overhead infrastructure also makes wireless systems much cheaper to build, and facilitates the planning and approval process. Although super capacitors are comparatively expensive at present, their costs are set to decline significantly in the near future.
During the operating phase, wireless tram systems provide safer and more convenient transportation, with no possibility of larger automobiles such as trucks colliding with overhead lines, and no need for clearances to pass beneath bridges.
One of the chief advantages of wireless trams is their energy efficiency, consuming 30 per cent less power than conventional systems. They also perform better during inclement weather, and remove ongoing costs in the form of investment in cathodic protection.
Urban planners overseas are already well apprised of the advantages provided by wireless trams. France's Altsom built the first modern wireless tram system for Bordeaux in 2003, while Spain's Trainelec has built wireless tram networks in the cities of Seville and Zaragoza, both of which make use of super capacitors.
China has also implemented wireless tram networks, turning to the systems to improve the sustainability and energy efficiency of the country's densely packed urban centres.
The Jiangsu capital of Nanjing will soon be host to a tram system which is 90 per cent wire free, while the mega-cities of Beijing and Guanazhou have started to unroll wireless lines that make use of super capacitor vehicles.
Given the enthusiasm that wireless systems currently enjoy overseas, Wright believes it's time for Australia to play catch up with international trends.
"These new trams have the potential to be a cheap solution to the congestion problems plaguing Australian cities, solving well-documented transport woes, unclogging roads, connecting disparate and ad hoc public transport and reducing local pollution," he said.