Interview with Josep Mension Camps ahead of the launch of the Barcelona Demo for the eBRT2030 project

Foreward: Josep Mension Camps, director Bus Central Services at Transports Metropolitans de Barcelona (TMB), the operator behind the Barcelona demonstration corridor in eBRT2030. The H12 line along Gran Via Corts Catalanes is one of the project’s most demanding test environments: a high-frequency, high-capacity urban corridor operating in the heart of one of Europe’s densest cities. We spoke to Josep to understand what running an electric BRT corridor looks like in practice, how TMB manages the realities of Barcelona’s streets, and what lessons the demonstration holds for other cities looking to electrify high-capacity bus services.

The Barcelona demo goes live on 8 July. If you would like to attend the launch event (virtually), you can register your place here.

Question: On a typical operating day, what does running the Barcelona eBRT demonstration corridor involve behind the scenes, and how does the urban environment factor into that?

Running the H12 corridor along Gran Via Corts Catalanes on a typical day involves a tightly coordinated system focused on maintaining a very frequent and evenly spaced service rather than adhering to a strict headway. Before operations begin, planners define frequencies and allocate articulated buses and driver shifts based on expected demand patterns. Once the service is running, the Bus Control Centre continuously monitors all buses in real time using GPS data and adjusts operations to keep regular headways, intervening when needed by holding vehicles, turning them short, or inserting additional buses to avoid gaps or bunching.

The urban environment of Gran Via Corts Catalanes strongly influences how this operation unfolds throughout the day. Despite dedicated bus lanes and some traffic signal priority, buses are still affected by congestion at intersections, unpredictable traffic behaviour such as delivery vehicles blocking lanes, and fluctuations in passenger demand at major nodes like Plaça Espanya or Glòries, which can increase boarding times and disrupt regular spacing. Additional factors such as roadworks, events, or incidents introduce further variability. As a result, running the H12 is essentially a continuous real-time adjustment process, where the system must constantly respond to the complexities of Barcelona’s dense urban setting to maintain a stable, high-frequency service.

Question: Barcelona’s streets involve intense competition for road space from private cars, tourists, deliveries, and other modes. How do you maintain service regularity in that environment?

In an urban context like Barcelona, where road space is heavily contested by private vehicles, delivery activity, taxis, cyclists, and pedestrians, TMB maintains service regularity on corridors like the H12 through a combination of operational control and targeted infrastructure measures, with a strong focus on stabilising headways rather than enforcing fixed schedules.

At the operational level, the Bus Control Centre continuously monitors bus positions and intervenes in real time to correct irregularities caused by congestion or uneven passenger demand. However, this alone is not sufficient in a corridor as busy as Gran Via, where delays are often generated externally, especially at signalised intersections. For this reason, TMB has progressively incorporated traffic management measures to give buses a structural advantage within the flow of traffic.

A key development on the H12 corridor has been the implementation of traffic light priority at 17 intersections along Gran Via. This system allows approaching buses to communicate with traffic signals so that, depending on conditions, the green phase can be extended or the red phase shortened. The objective is not to give absolute priority at all times, but to reduce stopping probability and smooth progression along the corridor. By doing so, buses experience fewer interruptions, more consistent travel times, and reduced variability between consecutive vehicles.

This intervention directly supports headway adherence. In a high-frequency system, the main risk is that a delayed bus accumulates more passengers, increasing dwell time and becoming further delayed, while the following bus encounters fewer passengers and catches up, leading to bunching. By improving intersection throughput and reducing random delays, traffic light priority helps prevent the initial disturbances that trigger this cycle.

The effect is particularly relevant on Gran Via, where signal density is high and intersections represent a major share of total delay. Even small reductions in stop time at each junction compound along the corridor, resulting in more regular spacing between buses. This infrastructure measure works in tandem with real-time regulation, allowing the Control Centre to operate in a more stable environment with fewer extreme interventions.

In summary, TMB maintains regularity on the H12 not only through active operational management but also by reshaping the urban traffic environment to favour buses. The activation of traffic light priority at 17 intersections is a key step in shifting the balance in a highly competitive road space, reducing variability at its source and making consistent headway operation achievable.

Question: Battery degradation in Spain’s heat and intensive daily use is a real operational risk in Barcelona. How does predictive maintenance factor into how you manage vehicle health and range reliability across the corridor?

Battery degradation under Barcelona’s high temperatures and the intensive duty cycles of a corridor like the H12 is managed increasingly through predictive maintenance, which shifts the focus from reacting to failures to anticipating them and protecting operational reliability.

In practice, each electric or hybrid bus continuously generates data on battery state of charge, temperature, charging patterns, energy consumption, and degradation indicators such as capacity fade and internal resistance. These data streams are analysed centrally to detect early signs of abnormal behaviour at both vehicle and fleet level. By identifying trends—such as faster degradation linked to repeated fast charging, high thermal stress, or specific duty cycles on Gran Via—TMB can intervene before performance drops affect service.

This directly feeds into how vehicle health and range reliability are managed on the corridor. Buses are not treated as interchangeable units; instead, they are dynamically assigned based on their effective range and condition. Vehicles showing early degradation or reduced usable capacity can be rotated to fewer demanding routes, while those in better condition are prioritised for high-demand, high-frequency routes like the H12. At the same time, charging strategies are adapted to minimise long-term wear, for example by optimising charging windows, avoiding unnecessary fast charging, and controlling battery temperature exposure as much as possible.

Predictive maintenance also informs operational decisions during the day. If a vehicle shows a risk of not completing its planned cycle due to range uncertainty, it can be proactively withdrawn or replaced before it impacts headway regularity. This prevents mid-service failures, which are particularly disruptive in a high-frequency corridor where consistency is critical.

In addition, aggregated fleet insights allow TMB to refine scheduling assumptions, incorporating realistic degradation curves rather than nominal battery capacity. This ensures that timetables, layovers, and charging plans remain robust over time, even as batteries age.

Overall, predictive maintenance acts as a bridge between engineering and operations: it protects battery health, stabilises available range, and ensures that vehicle performance remains aligned with the demanding, continuous operation required on the H12 corridor, even under the thermal and usage stresses typical of Barcelona.

Question: Decarbonisation is central to Barcelona’s urban mobility agenda. How does the eBRT project’s demo in Barcelona connect to the city’s broader climate and air quality goals?

The eBRT2030 Barcelona’s Demo Use Case is directly aligned with the city’s broader decarbonisation and air quality strategy by showing how high-capacity bus corridors can deliver metro-like performance with zero or low emissions.

At a strategic level, Barcelona aims to reduce greenhouse gas emissions and improve urban air quality by shifting mobility away from private cars toward efficient, electrified public transport. Corridors like the H12 are central to this approach because they concentrate demand into high-frequency, high-capacity services that can move large numbers of passengers with fewer vehicles and lower per-capita emissions. The eBRT2030 project builds on this concept by integrating electric buses, energy-efficient operations, and intelligent systems into an already high-performing corridor.

The demonstration contributes by validating electric bus operations under real urban conditions, including intensive use, high passenger turnover, and challenging factors such as heat and congestion. By proving that battery-electric buses can reliably operate on a demanding axis like Gran Via, the project reduces uncertainty around full fleet electrification and supports scaling up zero-emission services across the network.

It also connects to air quality goals at street level. Gran Via is one of the city’s busiest corridors, where emissions from traffic have a direct impact on local pollution. Replacing conventional buses with electric vehicles eliminates tailpipe emissions such as NO₂ and particulate matter along this axis, contributing to healthier urban environments, particularly in densely populated areas.

In addition, the eBRT2030 approach enhances efficiency through measures like traffic signal priority, energy monitoring, and optimised operations. These reduce unnecessary stopping, smooth driving patterns, and lower overall energy consumption, further reinforcing climate benefits. The combination of electrification and operational optimisation ensures that emissions reductions are not just theoretical but achieved in day-to-day service.

Finally, the project serves as a demonstration platform for integrated solutions, linking vehicle technology, infrastructure, and data-driven management. This systems approach is essential for achieving Barcelona’s long-term climate targets, as it shows how zero-emission mobility can be deployed at scale while maintaining service quality and reliability.

In summary, the Demo Use Case connects to Barcelona’s climate and air quality goals by turning a major urban bus corridor into a real-world example of high-capacity, zero-emission public transport that is operationally viable, scalable, and capable of delivering tangible environmental improvements.

Question: What operational insight from the eBRT demo in Barcelona do you think would be most valuable for other Southern European or Mediterranean cities looking to electrify high-capacity bus corridors?

The most valuable operational insight from the eBRT2030 demo in Barcelona is that electrification alone is not enough—stability in high-capacity corridors depends on integrating vehicle technology with operations and urban traffic management.

In practice, Barcelona shows that maintaining reliable electric bus performance in a Mediterranean context requires a system approach. Battery behaviour, for example, is highly sensitive to heat, intensive cycles, and stop-and-go traffic, so range reliability cannot be treated as a fixed parameter. Instead, it must be actively managed through predictive maintenance, adaptive vehicle assignment, and carefully designed charging strategies. This is particularly relevant for Southern European cities with similar climate conditions.

At the same time, the demo highlights that operational regularity must be protected at network level, not just at vehicle level. Measures such as traffic light priority, dedicated lanes, and real-time headway control are essential to reduce variability, which otherwise increases energy consumption, accelerates battery wear, and undermines service quality. In other words, smoother operations are not only better for passengers but also for battery longevity and overall system efficiency.

Another key takeaway is the importance of data-driven decision-making. The predictive demand model developed by the CRM (Centre de Recerca Matemàtica) for the H12 corridor is essentially a data-driven tool designed to anticipate how passenger demand evolves along the line in space and time, supporting better operational decisions. Besides, continuous monitoring of vehicle performance, energy use, and service regularity allows operators to anticipate problems and adapt both maintenance and operations dynamically. This reduces risk and makes electrified high-frequency service viable under real urban pressures.

For other Mediterranean cities, the lesson is clear: successful electrification of high-capacity corridors depends on aligning infrastructure, operations, and fleet management as a single system, rather than treating electric buses as a simple replacement for diesel vehicles.