This summer, Transports Metropolitans de Barcelona (TMB) will implement an innovative pilot test of smart ventilation regulation in the metro network to improve environmental quality, hygiene and passenger comfort in stations. The digitization project has been developed in concert with SENER Engineering, which supplied its RESPIRA^® control system. This project follows up on previous work carried out on line 1 to verify the importance of dynamic ventilation control, and which managed to lower the ambient temperature.

RESPIRA^® is an artificial intelligence platform that is capable of lowering the heat index of passengers and metro workers by defining several criteria and reading parameters in real time, such as the temperature, humidity and indoor air quality in the stations and electricity consumption. These data are used by a dynamic algorithm to predict the environmental conditions inside stations (depending on the weather forecast, expected ridership levels and other factors) and then apply a mode of operation to each fan with the goal of improving the heat index while also minimizing electricity consumption.

The conventional lines of the Barcelona (1 to 5), which transport 94% of all riders, will be used to test this advanced ventilation regulation model starting in July. Metro de Barcelona is currently carrying out some preliminary work, namely: adapting the control and regulation programs of the entire conventional ventilation network (187 station fans and 142 tunnel fans), developing new features for controlling fixed installations remotely, and equipping part of the network with temperature and humidity sensors.

For the director of the metro network, Ramon Bacardí, this is a «good example of applying technology to improve service quality and have a direct effect on the customer’s travel experience.» He also noted «the contribution of the ventilation system to provide a safe and comfortable environment for the metro network at a time when passenger volume is rising once more. Also, for reasons of sustainability and social equality, we need for public transport to be seen again as the best option for metropolitan mobility in the Barcelona area.»

The Director of Innovation at SENER, Òscar Julià, says that «RESPIRA^® is one of the many digitization initiatives that the company is currently working on. For SENER, the digital transformation involves integrating new technologies into businesses from the start, the ultimate goal being to make them available to society through innovations that improve people’s lives and are sustainable and environmentally friendly.» He added, «In the current context, RESPIRA^® can also play a very important role in improving the health and comfort of hundreds of thousands of riders who use the metro annually as a way to reach their destination.»

Against the spread of COVID-19

Smart ventilation control will maximize the amount of fresh air from the outside, a measure that will allow for increased hygiene inside the metro network and reduce the risk of spreading the coronavirus, which is responsible for COVID-19, and other microorganisms, in keeping with guidelines from health authorities. The enhanced environmental conditions in the stations in terms of temperature and humidity will be noticeable in the form of improved comfort for both passengers and employees.

Currently, this test project in the Barcelona metro is being studied by the Spanish Ministry of Science and Innovation as a solution that can be extrapolated to other large infrastructures.

The project also offers a series of advantages to the operator, such as equipment availability, rapid detection of abnormal operations, improved maintenance, lower electricity consumption, maximum performance of the installation and help in determining those areas where new investments are justified from a cost/benefit ratio perspective, thus contributing to the efficient and sustainable management of assets.

Comprehensive engineering study of Line 1

TMB and SENER previously collaborated on a pioneering and comprehensive engineering study of the ventilation in line 1 of the Barcelona Metro. For the first time in an operational transportation network, the infrastructure, trains and equipment were mathematically modeled and all possible operating modes of the ventilation and the existing infrastructure were studied analytically. As a result, in March 2019, the ventilation setpoints were changed, yielding a 1.2º C reduction in equivalent days compared to the previous year in the hottest stations on the line.

The new ventilation regime, implemented on the five conventional lines, involves exhausting air through the ventilation shafts in the tunnels and channeling it through the station fans and access points, maintaining the same air flow throughout the year. The key element is to take advantage of low temperatures in winter and nighttime periods to gradually lower the average temperature in the tunnels. This strategy has already allowed a first step to be taken in increasing the amount of fresh air from the street in passenger areas as a way to prevent COVID-19.

Reducing the temperature was one of the objectives pursued. But the study also demonstrated the importance of properly operating the ventilation equipment and hinted at the possibilities of a smart and dynamic control method that takes into account the ambient conditions outside and inside the stations to provide for an optimized ventilation strategy by sending individual setpoints to the fans, based on the time and day. This opened the doors to the digital transformation of one of the basic systems of the Barcelona metro infrastructure. 

Sener and Ferrocarril Metropolità de Barcelona (FMB) have signed a collaboration agreement to launch a new initiative called RESPIRA^®, whose main objective is to improve passenger comfort inside Barcelona’s metro stations through the efficient and optimised use of ventilation systems.

RESPIRA^® is an artificial intelligence system that will make it possible to set up an ideal ventilation strategy for each of the metro lines, in terms of improving comfort and energy efficiency. The new system, developed by Sener, takes into account the temperature perceived by passengers and workers by using a comfort index, as well as various criteria and variables, such as temperature, humidity, air quality inside the stations and the electrical consumption of the ventilation. With these data, it implements a dynamic algorithm for predicting environmental conditions inside the stations. Additionally, the system can also be used to make long-term forecasts, thus allowing FMB to prioritize future investments and maintenance work.

Sener’s Director of Innovation, Òscar Julià, states that «RESPIRA^® will be used to monitor and process over 500 million datapoints a year. Thanks to its self-learning process, the system will be able to adapt and act in advance.» By maximising the performance of the current shafts and fans with the help of artificial intelligence, the system will reduce the average temperature of the tunnel, improve air quality and thermal comfort for the more than 400 million journeys made by the Barcelona metro every year.

In the initial phase, the system will be installed in Line 1 in May of this year, where it will be used to control all the fans. In the remaining lines of the conventional network (lines 2, 3, 4, 5), the system will be phased in throughout 2020.

Main advantages of RESPIRA^®

On the one hand, RESPIRA^® will be used to monitor the environmental conditions inside the stations (temperature, humidity, heat index and air quality, among others) in real time, which will be useful in identifying problem spots within the metro network.

And, on the other, it will be used to monitor the operation of the fans and their effect on indoor temperatures, which will be of significant help to the maintenance activities required for the installation and to the efficient management of future investments.

This initiative is consistent with the following Sustainable Development Goals (SDGs) approved by the UN:

• Enhance the health and well-being of metro users by improving the thermal comfort and air quality.
• Help use energy more efficiently by saving up to 30%, and contribute to reducing the carbon footprint by more than 700 tons of CO₂ a year.
• Develop an advanced technology system with a distinctly innovative nature.
• Offer an environmentally friendly product that promotes sustainable development by minimizing equipment operating hours, reducing wear and tear, the maintenance and/or replacement period of the equipment, all while helping manage future investments in the ventilation system.

The RESPIRA^® project is one of the digitalisation initiatives of Sener, a technology group with more than 60 years of history, which has been a leader in innovation in many sectors of activity. For Sener, the digital transformation does not consist of using new technologies, but of integrating them into the business from its conception, and in line with the company’s founding vocation: to put technology at the service of society, providing innovations capable of improving people’s lives and that are sustainable and environmentally friendly.