WIRELESS ELECTRIC PROPULSION LIGHT RAIL TRANSIT SYSTEMS IN SPAIN

WIRELESS ELECTRIC PROPULSION LIGHT RAIL TRANSIT SYSTEMS IN 1 SPAIN 2 3 Francisco Calvo (corresponding author) 4 Civil Engineer. PhD. Associate Professor. 5 University of Granada 6 E.T.S.I. Caminos, Canales y Puertos 7 Avda. Severo Ochoa, s/n. 8 18071 – Granada (Spain) 9 +(34) 958 249452 10 [email protected]11 12 13 Andrew Nash 14 Emch+Berger AG Bern 15 Schlösslistrasse 19, 3008 Bern, Switzerland 16 Tel: +43-676-933-0483 17 [email protected], [email protected] 18 19 20 Submission date: Jul. 10, 2017. 21 Number of words: 6,871. 22 Number of figures and tables: 0 figures, 2 tables. 23 24 25 ABSTRACT 26 A frequent criticism of new light rail transit systems is the negative visual impact of overhead 27 power lines (catenary). Vehicle manufacturers have recognized this problem and developed 28 systems that allow trams to operate without catenary. There are three main approaches: 29 providing electricity from ground level systems, storing energy on-board the vehicle, and 30 generating power on-board the vehicle.In most cities where alternatives to catenary power 31 lines have been implemented they are only implemented on particularly sensitive sections of 32 the routes. This has been the case in Spain where three of 11new light rail systems have 33 adopted a hybrid electrification system using on-board energy storage. Spain’s experience 34 with hybrid electrification provides a good case study of the technology. 35 This paper summarizes light rail system development in Spain. It focuses on 36 comparing LRT systems that use hybrid electrification versus those that do not. The research 37 confirms, consistent with previous research, that the costs for systems using hybrid 38 electrification are higher than for those using catenarypower lines. The research also shows 39 that increased streetscape redevelopment – often required in places where visual impacts need 40 to be addressed with hybrid electrification – are a key driver of these increased costs.Finally, 41 an interview with the operator managers of the 3 LRT systems that use hybrid electrification 42 was carried out to understand key operational differences between the two systems. 43 44 Calvo,Nash  2 INTRODUCTION 1 New light rail transit (LRT) systems have been built in 11 Spanish cities since 1994. The wide 2 variety of different urban contextsand needs has led these cities to adopt different designs and 3 operating practices. One important difference is in power supply: three cities have built 4 LRTlines without catenary power lines on at least part of their route. 5 The traditional approach for providing electric power to light rail vehicles has been 6 with overhead power lines. Overhead power supply is a proven and well understood 7 technology. However, overhead power lines are considered by some to be unsightly and this 8 potential negative impact has been seized upon by opponents of light rail lines as an argument 9 against their construction. 10 Consequently, many cities considering new LRT lines in recent years have sought 11 solutions for providing power to light rail vehicles without using catenary power lines. 12 Vehicle manufacturers and public transport construction companies recognized this demand 13 and have developed several solutions. These solutions require vehicle manufacturers to work 14 together with the infrastructure providers to ensure that the vehicles can be provided with 15 sufficient power to operate. 16 There are three main methods for providing power to vehicles without using catenary 17 power lines (1): 18 1. Ground level power supply (GLPS) – power continuously supplied to the vehicle at 19 ground level via direct contact with a conductor or inductively; 20 2. Onboard energy storage system (OESS) – power stored on the vehicle, using 21 flywheels, batteries, supercapacitors or a combination thereof, recharged periodically 22 via regenerative braking and contact with a power conductor; and, 23 3. Onboard power generation system (OPGS)– power continuously generated on the 24 vehicle as required via hydrogen fuel cells, microturbines or diesel engines. 25 The three Spanish cities that use alternative power distribution all use OESS, more 26 specifically the ACR (Rapid Charge Accumulator) system developed by CAF 27 (Construcciones y Auxiliar de Ferrocarriles) and the Technical Institute of Aragón. All of 28 them have constructed systems with catenary power lines on some sections and without 29 catenary on other, more visually sensitive, sections (this combination of with and without 30 catenary is referred to as hybrid below). 31 The objective of this paper is to describe the experience of Spanish LRT systems 32 operating without catenarypower supply. Section 2 summarizes LRT systems in Spanish 33 cities. Section 3describes the wireless electric propulsion system used in Spain, lessons 34 learned regarding this system, and briefly discusses a survey designed to better understand 35 neighborhood resistance to new LRT lines (since one reason for choosing OESS is to satisfy 36 people who object to the catenary wires). Finally, Section 4presents conclusionsand 37 recommendations. 38 39 LIGHT RAIL TRANSIT SYSTEMS IN SPAIN 40 Spain has made significant investments in its urban rail networks during the last 25 years. 41 Cities have built new regional rail lines, metros and LRT systems. This section presents a 42 Calvo,Nash  3 brief description of light rail lines built in 11 cities. It begins by describing LRT in 8 cities 1 that have built systems with catenary power supply and then describes 3 cities where some of 2 the LRT line sections were built without catenary power supply. 3 Most of Spain’s new LRT systems were inauguratedbetween 1999 and 2008 when 4 Spain experienced a period of great economic expansion. This made financial resources (both 5 public and private) available for building new transport infrastructure. Many cities invested in 6 public transport to improve urban transport sustainability. Often, these investments were 7 made in smaller cities or in peripheral areas of large cities, which has caused them to have 8 relatively low demand. 9 When the economic crisis arrived in 2008 funding was drastically reduced and demand 10 fell, which put many lines in difficult situations (e.g., financial problems in the Parla LRT, 11 construction delays in Granada, suspension of service on the Vélez-Málaga LRT, non-12 inauguration of the Jaén –AndalucíaLRT). On the other hand, some of the LRT lines were 13 successful despite the difficult economic conditions, and so network extensions are being 14 planned (Vitoria LRT and connection of the two tram networks in Barcelona). 15 16 LRT Systems with Catenary 17 The first of Spain’s new generation LRT lines were built with conventional power supply 18 based on overhead lines (catenary). The same electrification system is used for the hybrid 19 LRT systems in those sections that operate with overhead contact system.All the LRT lines 20 installed simple aerial lines (without supporting cables) to reduce the visual impact on the 21 urban environment. 22 23 Madrid 24 Madrid has a population of 3.17 million inhabitants (2). Madrid has three LRT lines (ML1, 25 ML2 and ML3), all of which were opened in 2007. Its three lines are located on the outskirts 26 of the city. These lines serve new urban developments in the case of ML1, and small towns in 27 the cases of ML2 and ML3 (Pozuelo de Alarcón, with 85,000 inhabitants and Boadilla del 28 Monte with 50,000 inhabitants) (2), as well as running through employment areas. 29 ML1 is a stand-alone line that runs between the metro stations of Pinar de Chamartín 30 and Las Tablas. It provides service to the new neighborhoods of Sanchinarro and Las Tablas. 31 The new lines were designed to help support development of these new neighborhoods, and 32 while a certain amount of development has taken place, the new neighborhoods near the line 33 can still be considered as “low intensity” development, and empty plots still can be found 34 along the line. This limited development has contributed to the low demand for this line (3). 35 A substantial portion of ML1 was built underground and this led to a quite high 36 investment cost of over 53 million EURO per kilometer (96million USD per mile) compared 37 to an average cost for Spain’s new LRT lines of approximately 23 million EURO per 38 kilometer (39.6 millionUSD per mile). This cost could have been reduced given that most of 39 the area involved was being developed simultaneously, and some sections of the LRT could 40 have easily been integrated into the wide roadway infrastructure, instead of building them 41 underground (for example, a 700 m -2,297 feetunderground section along Príncipe Carlos 42 Street, which has a width of 60m -197 feet-) (4). 43 Calvo,Nash  4 ML2 runs through the outskirts of Madrid from the subway station of Colonia Jardín 1 (common station with ML3) to the commuter railway station of Aravaca, going through the 2 town of Pozuelo de Alarcón. It has 12 stations. It provides service to office buildings, 3 shopping malls and university campuses. Except for its two ends, ML2 goes through a 4 sparsely populated area with no chances of being urbanized (1). Its high average cost of over 5 34 million EURO per kilometer (61 millionUSD per mile) can be attributed to the many 6 underpasses and overpasses built to avoid level crossings with area roadways. Again, costs 7 could have been reduced by avoiding unnecessary underpasses and overpasses by changing 8 them by level crossings and installing traffic signal priority systems for the LRT (4). 9 ML3 runs from the metro station of Colonia Jardín to Boadilla del Monte. It has 16 10 stations. This interurban radial line provides service to leisure areas, office buildings and 11 university facilities. Like ML2, ML3 runs through sparsely populated areas, apart from both 12 ends (Calvo et al., 2013). The average cost of this line was approximately 22 million EURO 13 per kilometer (39 million USD per mile). This cost could also have been reduced using the 14 same strategies mentioned above for ML2. 15 Madrid’s three LRT lines have a ridership of over 16 million passengers per year (5). 16 The rolling stock is composed of 35 Alstom Citadis 302 trainsets (8 trainsets for ML1, and 27 17 trainsets for ML2 and ML3). 18 19 Parla 20 Parla is a suburban city located in the south of Madrid with a population of approximately 21 125,000 (2). The Parla LRT opened in 2008. It is a circular tramline that runs onthe surface. It 22 has 15 stations, one of them connecting with the suburban rail network of Madrid. The 23 average cost of this line was 17.7 million EURO per kilometer (32million USD per mile). 24 Parla’s LRT operates mostly through the outskirts of the city although a small portion 25 of the line runs through the city center. The LRT provides service to several industrial areas 26 and the neighborhood of Parla Este. This district is characterized by low intensity building 27 and unbuilt plots. This line has a ridership of 5.4 million annual passengers (6). The rolling 28 stock consists of 9Alstom Citadis 302 trams. 29 The municipality of Parla was supposed to pay 33% of the LRT’s investment cost 30 which it expected to obtain from the new urban developments in Parla Este. However, the 31 economic crisis meant that the area did become urbanized and many plots remained empty. 32 Therefore, in 2011, the system entered a financial crisis. There was even a temporary service 33 disruption. Finally, the City Council renegotiated the debt and the tram kept operating 34 normally. 35 36 Barcelona 37 Barcelona (1.6 million inhabitants) (2) has two independent LRT networks: Trambaix and 38 Trambesós. The Tambaix network consists of three lines (T1, T2 and T3) located on the west 39 side of Barcelona. It has 29 stations and connects Barcelona with the surrounding cities of 40 L'Hospitalet de Llobregat, Esplugues de Llobregat, Cornellà de Llobregat, Sant Joan Despí, 41 Sant Just Desvern and San Feliú de Llobregat. 42 Calvo,Nash  5 The Trambesos network consists of three lines (T4, T5, T6) serving the east side of 1 Barcelona and the satellite towns of Sant Adriá de Besós and Badalona. The Trambesos 2 network includes 27 stations. The tram lines on both networks operate through densely 3 populated areas, so they capture a high demand (26.8 million passengers per year). The first 4 sections were inaugurated in 2003, and last in 2007. The average cost of these lines was 5 approximately 25 million EUR per kilometer (45 millionUSD per mile). The relatively high 6 cost is due to building in a dense urban area where many utilities needed to be relocated. 7 Barcelona is currently considering the possibility of connecting the two systems with a 8 new 3.8 km line. The new line would have five stations and would double the current demand 9 (7). Both networks use Alstom Citadis 302 trams (23 train units in the Trambaix network and 10 18 in the Trambesos network). 11 12 Bilbao 13 Bilbao is an industrial city located in northeast Spain. The city’s population is 345,000 (2). 14 The Bilbao LRT opened in 2002. The average cost of this line was 9.5 million EURO per 15 kilometer (17.3 million USD per mile). 16 The LRT of Bilbao helps improve public transport, but the project’s main objective 17 was boosting the image of Bilbao, in conjunction with the Guggenheim Museum. The 18 approximately 5.5 km line is runs along Bilbao’s river (behind the museum). It consists of 14 19 stations serving the central city, museum, and metro and commuter rail stations. This line 20 serves a demand of 2.9 million passengers per year (8). The rolling stock consists of 8 CAF 21 Urbos I trams. 22 23 Tenerife 24 Tenerife is an island located off the coast of Moroco (Africa). It is part of Spain and a very 25 popular tourist destination. The LRT network of Tenerife has two connected lines (the first 26 opened in 2007), serving the cities of de Santa Cruz de Tenerife (204,000 inhabitants) and 27 San Cristóbal de la Laguna (153,000 inhabitants) (2). 28 Both LRT lines traverse heavily populated zones and provide service to hospitals, 29 museums, university centers and interchange stations. There are 21 stations in Line 1 and 6 30 stations in Line 2. They attract an annual demand of 13.5 million passengers (9). The 31 relatively high unit cost of Tenerife’s LRT (approximately 23.5 million EUR per kilometer) is 32 mostly due mostly to the complicated topography of the area where Line 1 was constructed 33 (2). The rolling stock consists of 26 Alstom Citadis 302 trams. 34 35 Vitoria-Gasteiz 36 Vitoria – Gasteiz is the capital city of the Basque Autonomous Community, located in 37 northern Spain. The city has a population of 245,000 (2). The LRT of Vitoria-Gasteiz opened 38 in 2008. 39 The LRT connects the city center with two branches leading to suburban 40 neighborhoods and forms a Y shape network with 18 stations. The line was built as part of a 41 Calvo,Nash  6 coordinated urban transportation strategy that included bus network re-planning, facilities for 1 active transport (e.g., comprehensive bike lane network) and urban design. This transport 2 strategy was one reason Vitoria-Gasteiz was named European Environmental Capital during 3 the year 2012. In 2015 this LRT was used by 7.7 million travelers (10).The LRT rolling stock 4 consists of 11 CAF Urbos II trams. 5 6 Murcia 7 Murcia is a city of 441,003 population in the southeast portion of Spain. The LRT of Murcia 8 began service in 2011. 9 The Murcia LRT has 28 stations andservesmostly low-density areas, such as 10 university, industrial areas, football stadium, shopping centers, sparsely populated areas and 11 neighborhoods of single family houses. The line serves an annual demand of 4.3 million 12 travelers (11). The rolling stock consists of 11 Alstom Citadis 302 trams. 13 14 Valencia 15 Valencia is a city of 790,000 population (2) located on the Mediterranean Sea south of 16 Barcelona. Valencia’s LRT was opened in May 1994 and was the first modern tram line in 17 Spain. Some of these lines come from the transformation of former narrow-gauge suburban 18 railways. 19 Currently, Valencia’s LRT network consists of Line 4 (opened in 1994 and expanded 20 in 2005), and Lines 6 and 8 (both opened in 2007). Line 4 (21 stations) connects Valencia’s 21 metroto areas of high demand such as university centers and Malvarrosa Beach. Line 6 (19 22 stations) aims to circumnavigate Valencia (although only the first section has been built). Line 23 8 (4 stations) connects Line 6 with lines 5 and 7 of Valencia’s Metro System, and with the 24 port of Valencia.The three lines amount to a total of 20 km, all running on surface. They have 25 an annual ridership demand of over 9 million passengers per year (12). The system uses 25 26 Siemens and 19 Bombardier Flexity Outlook Cityrunnertrams. 27 28 Hybrid LRT Systems 29 Hybrid LRT systems use a combination of fixed overhead wires and onboard power supply to 30 provide electricity to trams. This section describes the hybrid LRT lines in three Spanish 31 cities. 32 33 Sevilla (Seville) 34 Seville is a city of approximately 691,000 (2) population in the southwest portion of Spain. 35 Seville’s LRT opened in 2007, and was expanded in 2011. 36 Seville’s LRT consists of a single short line running from the historic city center to 37 San Bernardo, where commuter and metropolitan bus stations are located. The LRT has 38 relatively high ridership (4.1 million passengers in 2015). (8) 39 Calvo,Nash  7 The LRT runs through some of the most scenic streets in Seville’s historic center. It 1 travels at a very low speed so tourists can use it to see the area comfortably. While the line 2 runs entirely on the surface, its operation through historic areas, which are very important for 3 tourism and urban development, led to relatively high costs (27.5 million EUR per kilometer, 4 50 million USD per mile). (4) 5 Initially Seville’s LRT was built with overhead wires, but in 2011 it was adapted to 6 operate without wires in the central historic area to minimize the system’s visual impact.The 7 rolling stock consists of 4 CAF Urbos III trams with the ACR system.The ACR system is 8 recharged at the stops by means of a rigid catenary section integrated in the marquee of the 9 stops. 10 11 Zaragoza 12 Zaragoza is the capital of northeastern Spain's Aragon region. It has a population of 13 approximately 660,000 (2). The LRT line of Zaragoza was opened in 2011 and cost 35 14 million EUR per kilometer(64 million USD per kilometer). The project included 15 comprehensive redevelopment from façade-to-façade and pedestrianizing of the streets it runs 16 upon. 17 In 2015 the LRT transported 28 million passengers (8). This high demand is generated 18 because the line links the city’s historic center with the two main suburban nodes 19 (Valdespartera and Parque Goya).The route runs the most part in double track with reserved 20 right-of-way and is 12.8km long (8 miles). 21 The LRT route runs through the historic center without catenary for approximately 22 two kilometers to reduce its visual impact. This is the longest wirelessLRT section in 23 Spain.The rolling stock consists of 21 CAF Urbos III trams with the ACR system.The ACR 24 system is recharged by third rail at stops. 25 26 Granada 27 Granada is a city in southern Spain’s Andalusia region. The city has a population of 28 approximately 235,000 (2). The Granada LRT line began construction in 2007 and was 29 inaugurated in 2017 (the period of works ended up being double of the planned one). 30 The Granada LRT has 26 stops (three of them underground), and it connects Granada 31 with the main cities of its metropolitan area: Albolote, Maracenaand Armilla. Due to its 32 metropolitan nature (the regional population is approximately 530,000) (2), the line provides 33 service to important regional destinations including the bus and train stations, industrial parks, 34 administrative, sports, hospital and university centers, as well as connecting with a new urban 35 development zone (13). The LRT line is 16 km long. The system has an estimated demand of 36 12.9 million riders per year (14).The Granada LRT project included comprehensive 37 redevelopment from façade-to-façade of the streets it runs upon. The route is mostly double-38 tracked with an exclusiveright-of-way, except for a 528-meter section on Calle Real de 39 Armilla, where it is a single track. There is priority for the LRT at intersections with road 40 traffic. 41 Calvo,Nash  8 The catenary line is of a tram type when it runs on surface, while in the underground sections 1 rigid catenary has been installed. The Granada LRT has four wireless sections of length: 2 1,016, 1,250, 870 and 1,560 m (15). Its rolling stock consists of 15 Urbos III trams with the 3 ACR system. 4 5 WIRELESS LRT SYSTEM EXPERIENCE IN SPAIN 6 This section summarizes key information and experience about the implementation and 7 operation of wireless LRT systems in Spain. It begins by outlining the main reasons for using 8 wireless systems. Next it describes the wireless power distribution system used in Spain. 9 Finally, it describes several aspects of operating experience. 10 11 Why wireless power distribution? 12 There is a great deal of general resistance to rail-based public transport operating on surface 13 streets in Spain. This resistance is often justified by the visual impact – people say they do not 14 want the overhead power distribution system – but thereal reason is often resistance to a new 15 mode of transport reducing space for private vehicles.For example, a recent survey in 16 Andalusia found that approximately 33% of residents disagree with reducing the space 17 available for cars to give it to public transport (16). Furthermore, many (45.4%) residents 18 consider LRT to be an inappropriate means of transport for their region (17). 19 One of the main strategies used by cities to address resistance generated by negative 20 visual impactis constructing wireless power distribution systems. This was especially 21 important in cities where the trams operate in historic areas such as Seville and Zaragoza. 22 Here the economic benefits of tourism were used to justify wireless systems. 23 In Seville, moreover, the overhead system had to be disassembled every year for the 24 passage of the Easter week processions. In Zaragoza, the public authorities promoting the 25 LRT systemdemanded from the tendering process that the LRT operate without cables 26 through the historic center. 27 Today, the practice of using wireless power systems is extending beyond the historical 28 centers. For example, in Granada, the wireless sections are outside the center. In thesecases 29 the reason for installing wireless sections was mainly to silence the protests of the neighbors 30 regarding construction ofthe LRT linein general and the presence of the cables in particular. 31 Furthermore, the Granada LRT was also built underground along 2.74 kmto satisfy 32 neighborhood concernsalthough the street is wide enough for surface running (30 m / 98 feet 33 wide). In fact, a multi-criteria analysis studyabout surface or underground layout alternatives 34 using a hierarchical analytical process concluded the surface layout was the best alternative 35 (18). 36 37 Wireless LRT Electric Power Distribution in Spain 38 As outlined above, there are three main types of wireless power distribution systems used for 39 LRT systems today: ground level power supply, on-board energy storage systems, and on-40 board power generation systems. These three technologies are fully described in (1) and (19). 41 Calvo,Nash  9 All three tram lines that operate wireless sections in Spain today use the OESS 1 approach. More specifically they use the Urbos III ACR (Acumulador de Carga Rápida –fast 2 charge accumulator-)rolling stock. The ACR system uses ultracapacitors to store and deliver 3 energy. The trams charge the ultracapacitors along the catenary sections, or at stops (the 4 charge cycle lasts between 20 and 30 seconds).The energy stored is then used to power the 5 vehicle as it travels between stops. The vehicles can travel between 1,000 and 2,000 meters 6 between charging, depending on the characteristics of the route, the required performance and 7 installed capacity (20).It is possible to add the ACR system to existing LRT rolling stock and 8 infrastructure. 9 The ACR system also allows trams to recover the energy produced during braking and 10 store it in the ultracapacitors. This helps the ACR system improve energy efficiency of the 11 LRT systemscompared to conventional trams. In conventional trains, braking energy can only 12 be recovered when another vehicle in the vicinity can use it. This can save up to 20% of 13 energy (21). In addition, the system offers autonomy to the vehicle when the power supply 14 fails. 15 The ultracapacitors store and deliver energyusing a purely physical process. They can 16 store large amounts of energy and provide high power levels almost instantaneously. There 17 are no chemical reactions in its operation. The ACR system durability is around fifteen years, 18 which means that they need to be replaced approximately half-way through the normal useful 19 tram life of twenty-five or thirty years (22). 20 The operation of a tram equipped with the ACR system is as follows (23): (1) the tram 21 departs the stop with theACR equipment fully charged; (2) when circulating on a wireless 22 section, the motors and the auxiliary equipment are fed with the accumulated energy; (3) 23 during the braking process, the kinetic energy is fully recovered and stored in the ACR, 24 thereby initiating its recharging process; (4) at the stop, and after the rise of the pantograph, 25 the charge of the ACR equipment is completed to start a new cycle. 26 Although all LRTs with a hybrid electrification system in Spain use the ACR system, 27 each of them has a different way of charging the ultracapacitors. In the case of Granada, the 28 ACR recharges directly from the catenary, before passing to the sections without catenary. In 29 the case of Zaragoza, there are no overhead wires at the stops. The ultracapacitors get 30 recharged by means of a skid that makes contact with a short third rail section at the 31 intermediate stops of the wireless section. The third rail is located in the ground. Two 32 beacons, one located on the ground and another on the tram, determine that the vehicleis 33 stopped in the proper position to recharge, and only then the third rail is electrified and the 34 skid descends. The ultracapacitors can be fully rechargedduring the normal commercial 35 stopping time. Finally, in the case of Seville, the trains recharge the energy through a short 36 section of rigid catenary installed in the stands of the stops. 37 38 Spanish Experience with Wireless LRT Systems 39 This section outlines several key lessons from the construction and operation of wireless LRT 40 lines in Spain. 41 42 Total Project Cost 43 Calvo,Nash  16 1 REFERENCES 2 (1) Swanson, J., and Smatlak, J. State-of-the-Art in Light Rail Alternative Power 3 Supplies. Prepared for: APTA / TRB 2015 Light Rail Conference. 4 http://www.heritagetrolley.org/images/State_of_the_Art_in_Light_Rail_Alternate_Po5 wer_Supply_11-13-15.pdf. AccessedMarch 23,2017. 6 (2) National Institute of Statistics, 2016. http://www.ine.es/jaxiT3/Datos.htm?t=2911; 7 Accessed June 5, 2017 8 (3) Calvo, F.J., de Oña, J. and Arán, F. Light Rail Transit Experience in Madrid, Spain 9 Effects on Population Settlement and Land Use. 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