Light rolling stock Tram-Train: Is it the right option for the Algarve Line?

Movimento Mais Ferrovia recommends a new type of train for the Algarve Line

The More Railroad Movement (MMF) presented its contributions to the construction of the Algarve Railway Strategy to regional and central government entities, with competences in matters of regional planning and development and railway transport, last March, and, more recently, on 19 July, at CCDR Algarve, within the scope of the public consultation of the region for The construction of the National Railway Plan.

In these contributions, the MMF includes railway infrastructure and rolling stock, having recommended for the Algarve Line a new type of train, light, offering a quality and dignified service, with a high frequency associated with an extension of the timetable, and more train stops. proximity of access to populations.

In other words, a rail transport service that meets the real needs of intra-regional mobility and constitutes a transport alternative to the congested EN 125 and the eccentric Via do Infante, which is much more efficient, sustainable and environmentally friendly.

This option is also based on the fact that the Algarve's coastal corridor, especially between Lagos and Vila Real de Santo António, resembles a “metropolitan area”, where a large part of the Algarve's population is concentrated, currently around 467 thousand residents, to which are added annually between 7 and 8 million tourists.

It should be noted that the Algarve Line crosses this entire territory and connects all urban centers to Sotavento, in the section between Faro and Vila Real de Santo António, and Barlavento, on the section between Estômbar and Lagos, which is an asset for intra-regional mobility.

Taking into account these peculiar characteristics, associated with the short distance between stops, and analyzing the entire offer of rolling stock on the market, the MMF considers the tram train the most suitable to serve the region. For a full understanding of this option, the concepts and advantages associated with tram trains.

>>This designation can be translated into the Portuguese-speaking railway technical literature as electric (tram) + train (train).

>>Born in 1992, in the metropolitan area of ​​Karlsruhe, having been expanding rapidly and universally, becoming the ideal means of rail transport for metropolitan areas with a minimum of 100 inhabitants.

>>They are electric sized and built in such a way as to be able to circulate on urban routes, with the rails embedded at the level of the road or pedestrian floor, and with reduced speed, reaching 70 km/h (standard), and also on conventional lines, established with a ballast structure and laying beams, with a maximum speed of 100 km/h (standard).

Figure 1 – Tram-train and tramway, of the Porto metro

>>Its weights, powers and speeds are located between the urban material (trams) and the suburban (commuter trains), (Figures 1 and 2) combining the flexibility, accessibility and speeds of both, as is desirable for the Algarve region.

Figure 2 - Commuter train and tram-train, Nantes

>>They are usually bidirectional, that is, they have a driver's cabin at both ends, which gives them versatility in terminal stations.

>>Can operate under all conventional electric traction systems, with monocurrent or bicurrent configurations, e. ex.: Metro do Porto (750 V dc), Cádiz (1,5 kV / 3 kV dc), Lyon (750 V dc / 1,5 kV dc), Karlsruhe (750 V dc / 15 kV 16 2/3 Hz ), Île-de-France, Nantes, Sheffield (750 V dc / 25 kV 50 Hz).

>>Can be built to any gauge, e.g. eg 1000mm, 1435mm, 1520mm and 1668mm.

>>Allow users to travel by the same means of transport, from the population agglomerates on the outskirts of cities directly to urban centers. This concept of tram train significantly facilitates mobility, discouraging users to opt for individual transport.

>>Potential the increase in the number of users, due to the convenience and reduction of travel times.

>>They are an ecologically sustainable means of transport, since pollution by greenhouse gases does not exist, and noise is greatly reduced compared to that generated by road vehicles, as well as by rolling stock equipped with traction systems with diesel engines . Furthermore, more than 90% of its materials are recyclable.

>>Its operating and maintenance costs are much lower than those associated with current rolling stock – UDD 0450 railcars. This cost reduction can make tariffs very attractive for users, and are normally lower than those charged for conventional rolling stock. Its operational reliability and availability is roughly 98-99%. Compared to current UDD 0450 railcars, energy savings and associated cost savings can be around 70-80%. In 2012, more than 25% of the expenditure on the regional train service on the Algarve Line was associated with repairs!!

>>They have an operational performance that means they consume up to 4 times less energy than a bus, and up to 10 times less than a car, even if it is utilitarian.

>>They are the most suitable rolling stock for operating on lines with a high number of stations and stopovers, that is, with very short distances between stops, and where it is imperative to optimize supply times, since their start-up accelerations and braking decelerations – 1,1 to 1,2 m/s2 – are higher than those associated with current rolling stock – 0,5 to 0,6 m/s2.

>>Their maximum gross weight per axle is much lower than that of UDD 0450 railcars – 11 ton versus 14 ton, 20% less – which causes less mechanical reaction on the track structure.

>>They are equipped with a regenerative braking system. Roughly speaking, the electrical energy recovered by 2 units during their braking may be enough to power 1 unit operating in traction.

>>They can be made up of 2 to 7 modules (vehicles), of shorter length than in conventional trainsets, and are also equipped with tilting articulation systems, so that they can be included in severe curves, with a minimum radius of curvature of the order of 20 -25 meters. They can also circulate in gradients up to 100 per thousand.

>>The mobility of users is excellent, as they are built with a high number of double access doors, usually 4 per vehicle, 2 on each side, and have ample spaces for transporting passengers with reduced mobility, bicycles and other luggage.

>>According to the operators' specifications, they can be built with the access philosophies LF - Low Floor (low floor at 70% or 100%), and HF - High Floor (high floor).

Figure 3 - Porto metro tram-train, in an urban circuit operating as a tramway (electric)


A highly successful case of “metro-tram train” is the Porto metro network, which came into operation on December 7, 2002. It connects seven municipalities in the metropolitan area, and consists of 6 lines, with one more planned, and 82 stations, with another 7 planned.

Its total length is 70 km, mostly on the surface, and 9,5 km underground, with a further 28 km under construction. Its search in 2019 registered a record 70 million users. The gauge is standard, 1435 mm, and current collection is aerial, through contact wire and pantograph. Its rolling stock park comprises 102 multiple electrical units, of which 30 are tram trains, with a maximum speed of 100 km/h (Figures 3 and 4).

Figure 4 - Porto Metro Tram-train, in a traditional line operating as a train (train)

Another case of success, quite recent, concerns the tram train in service in the metropolitan area of ​​Cádiz, with a standard configuration of 3 vehicles, operates in 1668 mm Iberian gauge, and with a maximum speed of 100 km/h (Figure 5).

Figure 5 - Tram-train from Cádiz, the traditional circular line


Author Prof. Carlos Cabrita, Rolling Stock Specialist, member of the Mais Ferrovia Movement