The International Light Rail Magazine
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Technology, reliability and resilience

Trams that run without an overhead power supply are the new 'vogue' for European systems.

On the key trends for modern LRT vehicle design…

Clive Pennington: “Each promoter will wish to distinguish their vehicles from similar fleets by either livery or cab front styling, and manufacturers have become adept at addressing this need. Undoubtedly this will continue, but it is becoming more cost-effective with the use of vinyl finishes, regardless of fleet size.

“Communications and the provision of passenger information are key, particularly when you consider that even humble bus stops are now equipped with passenger information displays (PIDs), providing up-to-the-minute data. Not so long ago the bus stop was a sign with possibly a shelter.

“Live information utilising tram management systems may also be an option, particularly where networks containing modal interchanges are considered. To this can be added the use of live media and the advertising opportunities that this presents.

“The tram must be considered, and rightly so in my view, as an integral part of the LRT system, particularly where interfaces are concerned – which is particularly important for ongoing maintenance.”

Mark Terry: “Promoters and operators are becoming more aware of the issues relating to the performance and maintenance costs associated with low-floor bogie/wheel technologies. Experience is proving that there is now a preference to lean towards conventional axle wheelsets over independent wheels; especially for older systems that have track that is less forgiving to some low-floor tram designs.

“Several manufacturers now offer revised designs that include conventional axles, whilst still providing the popular step-less low-floor experience.”

On maintenance…

CP: “Reliability is a key operator deliverable and a key customer requirement of any successful system. This is particularly important as tram systems develop into true networks of interconnecting lines where the impact of any failure, be it tram or infrastructure, is felt much sooner and by more people.

“The tram is a key component of the system and having ever more reliable trams, and infrastructure, is an essential requirement on which to offer a good service.

“The trams are an expensive component of any scheme and operators will wish to maximise the utilisation of this asset. Currently tram maintenance is carried out at around 20 000km (12 000-mile) intervals; a challenge for manufacturers is the practicality to increase this periodicity, possibly resulting in fewer trams being required.

“Given the progress in technology, electronic systems will likely become obsolete before the predicted 25-30 year lifespan of the vehicle. Having systems that can be readily upgraded to avoid costly and early replacement is important to system owners if the predicted life is to be realised. Not unreasonably, they will want vehicles that will last.”

On the 100% low-floor debate…

CP: “Manufacturers appear polarised on 100% high or 100% low-floor vehicles. Does this mean that the 30/70% split is now no longer an option for future builds?

“However, vehicle width is very much driven by the geography of the system, with width being determined by factors such as the urban infrastructure, and manufacturers will need to continue to provide varying width options, despite
2.65m being seen as standard.”

On technical innovation…

CP: “Energy-saving technologies such as supercapacitors have been much lauded but have yet to make a real impact. The same is true for infrastructure-based options.
The adoption of such technology is not currently incentivised by existing franchise models where you have a private sector operator, owing to a separation of construction and operating (energy) costs between a promoter and a private sector operator. This will become increasingly important as energy costs and sustainability take on an ever-increasing focus.

“Wire-free operation is now effectively proven and must be a serious consideration, particularly in areas where low impact is required and to ease issues such as EMC.”

MT: “Promoters are under considerable pressure to be seen to be more environmentally-conscious, which includes looking at catenary-free solutions.
One of the challenges for the industry is to look at ways of making OCS-free systems cost-effective, as lifecycle costs are still considered too high to get these systems up and going.

“The automotive industry is under pressure to provide and increase the number of hybrid technology vehicles, so hopefully the cost benefits for energy storage will ultimately be felt by the LRT industry as economies of scale will swing the balance in favour of this technology.”

CP: “Cities, for example in the UK, keen to develop a tram system all too often look ‘over the fence’ to see systems such as Nottingham or Manchester, and like what they see but are concerned they can’t afford or justify the cost.

“If more systems are to be developed, particularly in smaller conurbations, a ‘lighter’ alternative is needed, perhaps following the Portland Streetcar example, to reduce the cost of the vehicles, infrastructure and the overall scheme.

“Whilst there has been much talk about reducing the cost of construction of street track – justified on the grounds that it should be a level playing field when comparing a tram to other road vehicles i.e. the requirements for the tram should be no greater than a 45-tonne truck – there has been relatively little movement. This, together with utilities diversions, keep tram construction costs disproportionately high.”

For the full version of this feature, please see Tramways & Urban Transit – January 2015 issue (925).