# High-Speed Rail in Spain
## Qualitative
### Introduction

The International Union of Railways’ (UIC) primary criteria for high-speed rail (HSR) travel is accommodating a commercial travel speed of 250km/h. HSR infrastructure operate at a significantly higher speed than traditional rail services, using a dedicated system of specialised trains and track. Infrastructure can be classified as ‘high-speed’ by the UIC if its function follows the following principles: track equipment, rolling stock, signalisation systems, operation, and geographic/temporal separation of freight and passenger traffic.
Currently, more than 20 countries have implemented high-speed rail, most of which reside in Asia and Europe. Early high-rail development was spearheaded by Japan, Italy and France in the 20th Century, but China now has the most extensive and widely-used high-speed rail system today.
Spain’s HSR network is called the Alta Velocidad Espanola (AVE). The AVE is operated and maintained by Renfe, the state-owned Spanish railway company. This network is comprised of almost 4,000 kilometers of track, marking it as the largest high-speed network of its type in Europe. Travelling at top speeds of 310km/h, this train system connects many major urban centres in Spain, allowing passenger travel from Madrid to Barcelona in less than 3 hours. The extensive network covers Seville and Malaga in the south, to Santiago and Barcelona in the north, to Valencia and Alicante in the east. Operating at full capacity, 500 trains travel the high-speed corridors daily, serving close to 40 million passengers in 2024.

### Technology

HSR requires dedicated infrastructure to accommodate speeds significantly greater than conventional/traditional passenger trains. Train speed is limited by the track it was built upon; high-speed trains cannot share the same tracks as freight trains. Furthermore, high-speed trains require electrical power supplied by overhead catenary wires over diesel fuel, as it is more energy-efficient and light-weight. HSR track must have minimal tight turns or changes in elevation, built in straight lines and longer curves to reduce friction and wear on train components.
The trains themselves need to be lightweight and aerodynamic, with the ability to accelerate quickly and efficiently. Inside, the journey must be quiet and smooth. Technological features of HSR are constantly changing, but core design features are kept. On-board signalling allows persistent monitoring and controlling by a central computerised facility. HSR trains are automated, ensuring punctuality and immediate stopping during emergencies. The aerodynamic design – streamlined shapes, tapered noses and smooth surfaces – reduce drag and maximise fuel efficiency. As mentioned previously, electrification is achieved through overhead catenary systems (wires), minimising weight by keeping energy sources off-train.
ADIF, the Spanish railway infrastructure operator oversees most of AVE’s day-to-day activities. Albacete’s Control and Regulation Centre (CRC) focuses on high-speed traffic. It is one of four central command centers that keep AVE and other rail infrastructure running. Logistically, 1,500 trains depend on the CRC’s overhead coordination monthly. Furthermore, remote CRC operators are in charge of managing railway traffic, power supply and communication systems.

###### Main Advantages

Ever since operation began in 1992, Spain’s high-speed rail network have served more than 400 million people. Passenger ridership continues to steadily grow year after year, with around 39.0 million passengers recorded in 2024, representing a 5% increase each year. Spain’s people and economy have benefited greatly from HSR. Through the AVE, Spain has facilitated a significant increase in accessibility and regional connectivity. The network connects 47 of Spain’s major cities and urban centres, serving 100,000 passengers daily. Smaller cities like Zaragoza, Valladolid and Girona are linked to major economic hubs in Madrid and Barcelona, opening up new markets.
Operating at higher speeds allows lowered travel time for commuters. The 620km trip from Madrid to Barcelona takes more than 6 hours by traditional car use. Through the AVE, the trip can be completed in less than 2 hours, halving the expected travel time. Furthermore, the increased accessibility boosts regional and cultural tourism. Greater access is provided to historical and cultural landmarks, notably in cities such as Seville, Cordoba, Toledo, and Granada, boosting Spain’s tourist revenue and international appeal.
Investments in HSR drives economic development, generating employment opportunities in infrastructure, engineering and transport industries. Furthermore, high-speed rail accessibility improves real estate development near key stations, attracting new businesses and commercial activity alike. AVE provides this with improved safety, reliability and punctuality compared to traditional rail services. The high-quality service and amenities – such as modern stations, air-conditioning, Wi-Fi – provides commuters with comfort and safety without compromising speed.
Furthermore, the AVE is a direct competitor to airline travel. Amidst the 21st century, growing concerns regarding greenhouse gas emissions and pollutions are increasingly prevalent in airline travel. HSR alleviates current road and air congestion problems; and subsequent pollution by reducing private vehicle dependency. AVE has become a significant contributor to decarbonising efforts spearheaded in Europe.

###### Main Markets

Spain’s geographic location makes it an important link between Europe, Africa and the Americas. The emergence of high-speed rail as an efficient and modern transport choice plays a role in boosting Spain’s domestic and international mobility. The AVE has enhanced both accessibility and regional connectivity, particularly benefiting Spain’s growing tourism industry.
Transportation and tourism are closely tied economic activities; the AVE connects the capital, Madrid, with the most prominent tourist destination cities in Seville, Barcelona and Valencia. For example, Madrid-Barcelona is the busiest and most profitable corridor, attracting both business travellers and tourists alike, and providing a fast, reliable and competitive alternative to air travel. Key primary markets for high-speed rail service include:
* Major urban centres and business travel
* Tourism and leisure travel
* Coastal and regional connectivity
* International travel
Given the high construction and operation costs of high-speed rail services, return on investment depends upon attracting sufficient passenger ridership and patronage. High-speed trains should link cities of sufficient size for a sizeable pool of travellers. Furthermore, these services are intended for a mix of medium-distance and long-distance journeys. The AVE also accommodates international travel, connecting Barcelona with Paris, Lyon, Marseille, and Toulouse through the high-speed network.

### Context

In the 19th century, the Kingdom of Spain was an agrarian economy – an economy that depended on the agricultural as its primary means of support. The nation had lagged behind its industrialising Western neighbours. Pioneered first in Great Britain in the 1820s, the first steam-powered railway corridor in Spain was developed along the coastal peninsula, connecting Barcelona and Mataro in 1848. By this time, France and UK had already developed extensive networks.
Spain has a relatively mountainous terrain with sparse inland waterways, separating regional and coastal settlements. Spain’s challenging geography severely restricted early railroad development. The nation’s railroad infrastructure was built ahead of demand in a country with a relatively low and scattered population density. Spain’s economic growth flourished at the coastal peninsula, marking coastal shipping as the dominant mode of trade. By 1848, there were only two canals operating within inland Spain. The Canal Imperial de Aragon (88km) and the Canal de Castilla (210km). The development of railways became a national priority. Private companies were primarily responsible for the construction of new infrastructure, although, many initiatives received Government subsidies. Before railroads, people and goods were transported overland and through coastal shipping. This mode had poor territorial reach and accessibility, and was a key factor in Spain’s economic stagnation during the 19th century.
Further delays in rail development was influenced by political instability following Napoleon’s defeat in 1815. The restoration of the Spanish throne escalated into civil conflicts like the First Carlist War, resulting in low government/public interest in building new railways. This unrest postponed rail infrastructure development must later into the 19th century. Furthermore, Spain’s gauge – rail width had also delayed progression. Spanish track had a1672mm gauge, instead of the 1435mm standard used in most of Europe. This choice was likely to differentiate from Francoist influence and avoid use during potential invasion, further delaying interoperability and expansion.
Rail transport revolutionised Spain’s economy. The reduced transportation costs allowed the growth of Spain’s key export industries – wine, citrus fruit, oil and raisins. Railways also influenced mining and manufacturing, making raw materials such as coal, iron and copper easier to extract and move. The expansion of the rail network provided greater accessibility, connecting the manufacturing producers along Spain’s peninsula to the consumers inland, marking the beginning of Spanish Industrialisation. Travel times were reduced, with estimates suggesting that by railway transportation shortened trips from Madrid to other provincial capitals by 60% compared to stagecoaches, later reaching 80% reductions by the late 19th century.
In the 1950s, the Spanish rail network reached its historical maximum, peaking at around 19,000 kilometers. Shortly after, the exponential increase in private vehicle ownership in Spain resulted in the railroad system shrinking. The decline in rail transport demand saw 8,000km of track being dismantled due to loss of profit. Economic challenges, its status as a conservative, Catholic nation, its geographical location and neutrality in both World War I and II, meant Spain’s rail network was less affected by global events, further delaying improvement. This established the setting for HSR’s deployment in Spain in 1992.

### Invention

The Industrial Revolution of the 19th century accelerated the development of rail transport in Europe. As train performance and commercial speeds continued to increase, the emergence of other transport modes – aviation (faster) and private cars (point-to-point travel), forced rail technology to innovate to keep up with competition. By the 1980s, Spain’s railway network was outdated and inefficient.
HSR network began its development in 1964, in Japan. The Japanese National Railways had unveiled the brand-new, 515km: Tokaido Shinkansen, connecting Tokyo Central to Shin Osaka. Operating at 210km/h, the Shinkansen introduced cutting edge-technology: a broad loading gauge, electric motor units powered at 25 kv AC, Automatic Train Control (ATC) and Centralised Traffic Control (CTC). Japan was the first to introduce a new standard of tracks (low curvature) and trains (light-weight). Following the technical and commercial success of the Shinkansen’s deployment, there were efforts to implement Japan’s concept of dedicated high-speed lines and train research in Europe during the 1960s. In 1981, France opened its Paris-Lyon LGV – the dedicated high-speed railway where its Train a Grande Vitesse (TGV) would run on. France would set the benchmark by which other European countries would replicate the deployment of the HSR. Afterwards, Spain and Germany would launch their own HSR projects.
In the late 1980s, Spain would draw up a new rail plan, with further revisions in 1993 and 1997. In 1992, Spain had inaugurated its 471 km-long HSR line, connecting the Madrid and Seville corridors. Spain’s HSR was heavily inspired by the deployment of France’s TGV. The AVE had imported expertise from France’s TGV for the first AVE line, but soon developed technological solutions tailored for the existing infrastructure. The implementation of a standard gauge, development of streamlined, high-speed trains from trains, extensive tunnelling to accommodate for Spain’s mountainous terrain were early strategies.
During the 2000s, Spain had developed its own Talgo 350 and Siemens Velaro based on earlier iterations of Spain and Germany’s HSR trains. Furthermore, the AVE would incorporate the European Rail Traffic Management System (ERTMS) – a system of standards for railway signalling management by the EU, replacing older signalling systems. Initially, the AVE was designed to expand radially from Madrid, but later expansions around Barcelona, Malaga, Granada created a more interconnected, nation-wide system.

### Role of Policy
###### Borrowed Policies

Spain’s AVE implementation in 1992 was highly influenced by the policies and practices of earlier HSR models – specifically the France’s TGV and Japan’s Shinkansen models. High-speed rail was launched first in Japan in 1964. Following huge technical and commercial success, France, Germany and Italy developed new technologies and innovations to adopt the initiative. Like France, Spain’s AVE replicated the idea of dedicated high-speed infrastructure, separate from traditional rail lines. Through this, the AVE was not constrained and could operate in higher speeds without being slowed down by mixed-traffic tracks. France’s emphasis on sustainability shaped AVE’s development and deployment.
Another key objective of the AVE was to connect major cities and regional hubs, whilst allowing integration with other modes of existing transportation. For example, Spain followed Germany’s Deutsche Bahn of integrating high-speed rail with local and regional transport systems. As mentioned previously, the inauguration of the AVE was a symbolic platform of Spain’s modernisation. Both France and Germany’s high-speed rail systems heavily emphasised sustainability. AVE’s use of energy-efficient trains and clean infrastructure reflect these values. To accommodate for this objective, Spain had borrowed technological innovation and safety standards from both Japan and France.

###### Innovation of Policies

Spain’s implementation of AVE was to not only connect major cities – like in Japan and France – but to foster economic growth by connecting to regional provinces. The design of the network was intentional in linking cities that could greatly benefit from high-speed rail access, allowing growth in underdeveloped regions and reducing regional disparities.

##### Government Imposed Policies - Locked-in Policies

The high-sunk cost of high-speed rail infrastructure required significant public investment from the state to support in construction. Infrastructure development, like roads, bridges and railways, do not follow normal market rules. Businesses invest in things that can quickly make money. High-speed rail is expensive to build, takes considerable time to pay off, and carries financial risks. Governments and public institutions often step into fund these projects, but private companies may not find them profitable enough.
Infrastructure development is a key sector for government investment – they are prioritised projects because they are important for economic growth. Public institutions play a big role. Spain, and other larger governing bodies (e.g., the EU) have been heavily involved in funding and guaranteeing these projects. The EU’s involvement in funding Spain’s high-speed rail infrastructure is significant. Spain joined the EU in 1986, and received substantial development funds, because it was perceived as a “weak” nation at the time. The ADIF Alta Velocidad (public infrastructure organisation involved in HSR investment) is the most heavily indebted public Spanish Company with around €18 billion in debt. The operation of the AVE network is handled by RENFE, the state-owned railway company. This was done to ensure that the AVE exceeded national standards for safety, punctuality and accessibility.

### Growth

Once the line was opened, it was slow to break into the market. Given the high-sunk cost of constructing the HSR corridor and the substantial debts Spain had owed the EU, there was much pressure on the AVE's immediate performance and return on investment. Recording around 1.3 million passengers in its first year, AVE's ridership steadily grew. By the fourth year, the line's ridership grew, showing more passengers and more public acceptance of the project.
In 1992, 34% of all trips from Madrid to Seville were on HSR. One report found that prior to HSR in 1999, the modal split was 44 percent road, 16% rail and 40% air. In 2002, 10 years after the implementation of HSR in Spain, the splits have increased to 30% road, 1% conventional rail, 61% high-speed rail, and 8% air. After continued success, Spain was eager to build more HSR corridors. The first step was to link Madrid and Barcelona. Currently, there are four main corridors that connect Madrid with other peripheral regions: Madrid-Catalonia, Madrid-Leon (Northern corridor), Madrid-Levante and Madrid-Andalusia.

### Maturity

Most of the AVE network was constructed with the international gauge - rail width of 1435mm. Previously, conventional/traditional trains in Spain circulated on the Iberian gauge - rail width of 1668mm. Further investment in Spain's HSR corresponds to several key objectives well after it was deployed. Further AVE expansion was associated with reducing congestion on conventional networks, modernising the country, reducing dependency on oil, improving regional connectivity and reducing travel times, both regionally and internationally. These aspects significantly influenced the AVE network's design and functionality choices for future expansion.
By 2000, Spain had the largest HSR network, surpassing France in total HSR kilometers of track. Continued patronage saw the number of HSR ridership steadily grow year after year, culminating to a peak ridership of almost 40 million in 2024. Historically, Spain has benefited from substantial EU grants for HSR initiatives. However, liberalisation has been driven by EU regulation - there has been a gradual opening up of competition rather than through state-owned agencies. According to Independent Authority for Fiscal Responsibility (AIReF), Spain's HSR projects have led to significant debt accumulation. In 2020, almost €56 billion had been invested into Spain's HSR, and around 25.2% (€14.09 billion) was financed through EU funding. A debt of around €15.9 billion is held by Adif Alta Velocidad, the Spain's state-owned infrastructure agency.
Historically, the average construction cost of HSR in Spain is around €14.7 million per kilometer, increasing to €15.3 million when including stations. Furthermore, maintenance costs are estimated to be at around €150,000 per kilometer per year. To alleviate these debts, ADIF opened up HSR services to competition. Three different companies won these packages, resulting in Spain's AVE running by multiple companies instead of one state-owned operator. Competition among HSR services is controlled to ensure network is well-organised and ADIF earns revenue from these operators. This liberalisation process has produced notable benefits for Spain's economy. Citizens can enjoy improved operator service quality and lowered prices. In 2023, ADIF has benefited from an additional €150 million in revenue, compared to in 2019.
Currently, the AVE's infrastructure funding is a combination of financing from the EU, Spanish state funds and private development. ADIF partially contributes to financing through user fees. Some of EU's sources include:
* Trans-European Transport Network (TEN-T)
* Cohesion funds
* European Regional Development Funds (ERDF)
The Spanish government is committed to HSR expansion, allocating 1.5% of the nations GDP to infrastructure investment until 2020.

## Quantitative
### Data

The purpose of this investigation is to briefly analyse and provide an overview of the AVE’s lifecycle. Observed data was collected from the annual reports published by the Instituto Nacional de Estadistica (INE), Spain’s official government agency.
From the INE database, the AVE’s monthly high-speed rail passengers from 1999-2023 were extracted and stored for further analysis. Initially, the data separated into months – for example, 2023M12 – so each month was aggregated to return a yearly value of travellers transported.

### Methodology

The AVE’s lifecycle was modelled as an S-curve, displaying AVE’s annual ridership over time. S-curves, which relate a status/dependent variable – are visual demonstrations that allow us to determine the periods of birthing, growing and maturing of the AVE.
To model projection, a logistic S-curve is a reasonable and sensible approach in assessing AVE’s lifecycle. A three-parameter logistic function was estimated using the observed data. To determine the accuracy of the model, the predicted and actual passenger ridership was plotted, with relevant statistical measures also included. The logistic function is described as:
$s(t)=k/[(1+\exp(-b(t-t_{i}))]$
Where:
* S(t) = status measure - passengers
* t = time in years
* t$_i$ = inflection year - year in which 0.5S$_{max}$ is achieved
* S$_{max}$ = saturation level - maximum annual AVE ridership
* b = coefficient to be estimated
The b coefficient was determined using the single variable linear regression in a model of the form:
$Y=bX+c$
Where:
* Y = ln(Passengers / S$_{max}$ - Passengers)
* X = Year

### Results and Interpretation

The logistical regression plots visually showcase the birthing, growth and maturity phases of the AVE. A table of the observed data and predicted ridership are shown in the table below. The years are given, and key events and policies are included to explain possible phenomenon in the curve.
| Year | AVE Ridership (thousands) | Predicted Ridership (thousands) | Notes. |
| 1992 | - | - | Madrid-Seville line inaugurated. HSR operation begins in Spain |
| 1993 | - | - | |
| 1994 | - | - | |
| 1995 | - | - | |
| 1996 | - | - | |
| 1997 | - | - | |
| 1998 | - | - | |
| 1999 | 5093 | 4472 | |
| 2000 | 6425 | 5246 | |
| 2001 | 6998 | 6141 | |
| 2002 | 7208 | 7171 | |
| 2003 | 7334 | 8349 | Madrid-Zaragoza-Lleida line opened (north-eastern corridor) |
| 2004 | 7560 | 9689 | |
| 2005 | 7176 | 11202 | Zaragoza-Huesca line opened Madrid-Toledo line opened |
| 2006 | 6518 | 12898 | |
| 2007 | 11409 | 14781 | Cordoba-Malaga line opened |
| 2008 | 22098 | 16851 | Madrid-Barcelona line opened |
| 2009 | 28750 | 19103 | |
| 2010 | 28056 | 21525 | Madrid-Cuenca-Valencia line opened (eastern corridor) |
| 2011 | 28899 | 24096 | |
| 2012 | 28393 | 26789 | |
| 2013 | 32123 | 29570 | Barcelona-Figueres line opened (Spain, France) Railway liberalisation begins |
| 2014 | 34100 | 32408 | |
| 2015 | 32621 | 35242 | |
| 2016 | 38829 | 38049 | |
| 2017 | 40259 | 40784 | |
| 2018 | 42002 | 43410 | Valencia-Castellon de Plana line opened |
| 2019 | 41222 | 45897 | Antequera-Granada line opened |
The accuracy of the plot was given by maximising the RSQ value. From the excel spreadsheet, this was achieved through trial-and-error, primarily by means of estimating the S$_{max}$ , the maximum predicted AVE ridership. An initial guess was an S$_{max}$ value of 50,000 (thousands). By inspection from the spreadsheet, a final S$_{max}$ value of 61,000 (thousands) was chosen to maximise the RSQ value of 0.9157. The closer the RSQ value is to 1.0, the higher the regression model's accuracy in predicting actual passenger journeys. This high value reflects an accurate model.
After completing the regression analysis, the estimated parameters from the plot above as are follows:
* RSQ - 0.9157
* t$_i$ = 2013.229
* b = 0.1800
* Intercept, c = -362.5337
* S$_{max}$ = 61,000 (thousands) or 61 million

### Analysis

Given the high RSQ value, the logistic model's growth is very similar to the actual passengers data. From the observed data, AVE ridership has been steadily increasing up until 2019. However, the ramifications of COVID are not present in the data - running a logistic regression on the COVID years (2020-2022), can lead to complications in the model's accuracy. Furthermore, the AVE began operations in 1992. 7 years of missing data is excluded from the regression analysis. It is assumed that the years prior to 1999 saw smaller annual ridership values, gradually increasing to the values showcased in 1999 to 2019.
From the scatter plot, the key phases in the AVE can be determined:
Birthing Phase: 1992 - 2006
Growth Phase: 2006 - 2018
Maturity Phase: 2018 - Present

### References

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