Latest Innovations in Streetcars

April 24, 2018
Urbanization, climate change, pollution and congestion are all driving the need for sustainable development in urban transportation and streetcar innovations are creating efficient, comfortable, safe options.

Light rail system openings represent significant growth in the rail market. Adapting to city infrastructure, incorporating newer technologies and tackling the cost associated with running a streetcar system are factors that come together to make a streetcar system a more attractive choice for an agency to add into its services.

Improved Operation

Alstom Tram Product Director, LRV Platform, Eric Caplot said Alstom launched the development of Citadis X05 three years ago. This latest member to the Citadis family features improved passenger comfort, optimized operation, increased modularity, lower operating costs and catenary-free options.

The Citadis X05 has up to an 18 percent reduction of preventative maintenance costs, based on Citadis REX and technical innovation. The easier sub-system integration and maintenance reduces the lifecycle costs, and with the ONIX 850 traction drive with closed self-ventilated permanent magnet motors and optimized heating, ventilation, and air conditioning function, there’s a 25 percent reduction in energy consumption.

In Atlanta, Siemens recently opened its Innovation Center and worked on developing the Atlanta Streetcar. The project worked to create a “smarter” streetcar. When approaching the project, Siemens looked at a connection of maintenance, vehicle monitoring and connectivity.

“The technology that is deployed is two-fold,” said Simon Davidoff, head of digital rail services, Siemens Mobility. “One is the connected vehicles. There is onboard technology, which, second-by-second transmits the position and operations of the streetcar. It also includes live video feeds that are internal and external. Basically it marries the digital view of the operations and the safety and operation aspects of the Atlanta Streetcar all in one package so they can have a fleet-wide view of the operation of the fleet.” Davidoff added that having the project proximity to the new center in Atlanta helped the Siemens team connect to the project on a more physical level.

The analytics from the data that are collected on the vehicles can be analyzed in numerous ways.

“The onboard systems were designed to track maintenance and track in an emergency, kind of like a black box technology. We are tracking simple things like when a door opens or closes, exactly what the position of the train, if it is stationary …,” Davidoff said. “We’re tracking speed, location, when the operator hits the brake or maybe hits the brake too hard and activates the emergency brake.”

With the Atlanta Streetcar, Siemens also collects data on passengers. The amount of passengers can be derived from the weight of the streetcar vehicle and the weight dispersion throughout it. The data relating to passengers also looks at how long the doors are open and which stations have longer boarding and off-boarding times. This can be analyzed by the agency to determine what stations are heavily used and what the peak times are.

Alexander Ketterl, head of FLEXITY product family, Bombardier Transportation, shared a number of ways that Bombardier is advancing in technology.

“Depending on customer preferences, both bogies comprising real-axle wheelsets, as well as independent wheels, are available,” said Ketterl. “The ODAS obstacle detection driver-assistance system will be further developed and allow for plenty of use cases.”

Bombardier also sees a need for a lower lifecycle cost. “Minimum maintenance effort during inspection, maintenance, overhaul throughout the lifetime of a tram,” Ketterl said.

He continued, “[We see a demand for] energy-efficient trams, not only traction energy but increasingly for all installed tram-equipment. Offering a superior passenger experience with maximum aisle- and gangway width throughout the complete vehicle and number of multifunctional spaces.”

Optimizing operating expenditure was key in the development of Alstom’s Citadix X05. While the price has to be considered, the system is to be used for 30 years, so cost of energy and cost of maintenance over 30 years are also key criteria.

As for passenger comfort, Caplot said the Citadis X05 has a larger central aisle and wider gangways to offer a spacious design. There is 40 percent more window surface, which also contributes to the open feel of the interior. To improve service efficiency, double doors provide a 15 percent passenger exchange ratio increase.

Increased modularity allows cities and operators to have a fleet that best meets its demands. More flexibility is obtained through a variety of configurations available with the Citadis: a small LRV can move about 130 passengers, medium about 305 and a longer configuration can move about 405.

Safety Improvements

Alexander Ketterl, head of FLEXITY product family, Bombardier Transportation, said they have been continuously working on improvements in passenger comfort and safety. “Going with the digital trend, we are the leading provider of safety technologies with our collision prevention for light rail vehicles. Our homologated system for obstacle detection and braking assistance uses 3D-stereo supervision and smart algorithms to recognize all sorts of objects and more importantly people, then to take action to help prevent accidents.”

Stadler has found that streetcar vehicles are more likely to be involved in an accident compared to light rail or heavy rail lines within cities.

“Since streetcars are really from time-to-time engage in an accident, the whole accident replacement discussion has some potential to be innovated,” said Ritter. “To be able to replace something very fast, because we have little damages on a streetcar more often than on a train. I also do believe that the discussion in North America with the 8-inch platforms and that is going to challenge how we can have such a low platform for level boarding for ADA access.”

Ritter also noted that currently streetcars are predominantly constructed out of steel or stainless steel as opposed to aluminum.

“What we try to deliver with our streetcar project is the reliability and the top quality besides being on time with the deliveries. I think it is the customized innovative approach that we deliver combined with components of a really proven design which is kind of changed to be focused on the customer’s needs,” said Ritter. “We do have a couple of ideas to make replacements for damages efficient and fast so you don’t need a lot of spare cars, you can run with most of your fleet. I think that with innovation we can provide. I think if people really want fancy stuff we can come in.”

Infrastructure Solutions

Cities and operators have options when it comes to powering the vehicles and Bombardier’s Ketterl said that requirements vary county to country. “On the European market we face mainly existing infrastructure with streetcars in the city center and increasing mixed traffic. Therefore, technical parameters and specifications are tight and indisputable versus the respective existing infrastructure and wayside-environments.”

He said, “In America we find new infrastructure where typically short streetcars are used as circulators.”

Ketterl said that Bombardier has implemented a plug-and-play catenary-free operation technology.

Alstom launched its latest innovation in catenary-free solutions with SRS, a ground-based conductive static charging system, designed to recharge vehicles equipped with onboard energy storage. The Ecopack SRS technology removes the cables and masts and stores energy on the vehicle and quick charge when the vehicle is stopped at stations.

Alstom Road Infrastructure Solutions Manager Philippe Veyrunes explained SRS is based off Alstom’s APS catenary-free solution, but only requires charging by contact at the passenger stop in 20 seconds, during normal dwell time.
The charging is automatic, not requiring anything of the driver. The fast charge happens via contact during the normal dwell time at the platform, in about 20 seconds at 750 volts. 13.5 kWh of energy is stored and the current maximum charging with SRRS is 1,600 amps.

Whether or not SRS is the right option for a system is whether or not catenary is wanted, the size of service and the line configuration.

If the agency wants catenary-free light rail operation, Alstom offers SRS or APS, which is continuous charge from a third rail. With continuing infrastructure between stations for APS, the costs are seen on the infrastructure side. SRS utilizes charging at the station and there is the extra equipment on the vehicle; there’s an equation to consider as one has higher costs on the vehicles, while the other has higher costs on the infrastructure.

For lines operating on hills, there can be increased energy consumption. The climate also can require a higher energy consumption with HVAC demands, so passenger comfort is always a consideration.

The Ecopack SRS solution can recharge LRV or electric buses equipped with on-board energy storage by contact in 20 seconds during normal dwell time at a stop or in a few minutes at the end of a bus line. Martin Ritter, president and CEO of Stadler US Inc., said that one issue facing the further implementation of streetcars can be seen within the necessary infrastructure.

“The downside of the streetcars right now is that they’re relatively expensive. We have to install overhead electrification we do have to track the infrastructure track work. We know in the industry where there is the concept that if you compare it with a trolley bus for example or with just a zero-emission bus,” said Ritter. “The other question is why a streetcar? In the industry some other competitors are also going with ‘trackless’ systems that look like streetcars, but they’re not really on the rail. They’re visual components that they are running on rails when they are really running on the street. On the other hand the whole off-wire battery streetcar discussion has potential. The zero-emission and (operating) without the overhead track, I think that is something that the industry could change down the road.”