Subway turned into power station

Most passengers exiting the station in Bellvitge, a working-class neighborhood on the outskirts of Barcelona, ​​have no idea how advanced the city’s metro system is. Using technology similar to regenerative braking in electric and hybrid vehicles, the trains they ride produce a portion of the electricity that flows into electric vehicle charging posts in nearby parking lots, station lights and elevators that take They arrived at the station and followed Popsci.

Every time the train is about to stop, the energy created by all the friction is converted into electricity, fed into the inverter and distributed throughout the subway system. One-third of that electricity runs the trains, with the rest used for station amenities and the growing network of EV charging stations.

The super-fast charging station outside Bellvitge station is among four charging stations installed in July. The main transportation service provider in the city, Transports Metropolitans de Barcelona (TMB), plans to add three more stations as part of the project. The project is called MetroCHARGE expansion. “We’re trying to take advantage of the electricity in the metro system and use that excess energy for electric vehicle charging posts on the street,” said Marc Iglesias, head of sustainable transportation at Àrea Metropolitana de Barcelona, ​​the regional agency. working with TMB on the project.

Each year, residents and visitors make 440 million trips using Barcelona’s metro system, which includes 165 stations linked by 125.5 km of tracks. Up to now, the traffic agency has installed 3 inverters and will add 13 more. Once it’s all installed by the end of September, they expect regenerative braking to provide 41% of the energy needed to run the train. This renewable energy source will help reduce about 3.9 tons of CO2 emissions annually.

Although many places, including Vienna, Philadelphia, and São Paulo, use regenerative braking to some extent, Barcelona is among the few cities to use it extensively and the first to harness that energy source for infrastructure. electric vehicle charging floor. Harnessing energy that would otherwise be lost as heat when trains slow down could significantly reduce the electricity consumption of public transport systems.

With the implementation of MetroCHARGE, 33% of the energy used by trains comes from regenerative braking, enough to power 25 metro stations, according to Jordi Picas, project leader and metro system director at TMB. . In subway systems that do not implement regenerative braking, there is too much unused energy, which is not only wasted but also produces heat that spreads inside the tunnel, increasing the temperature. Since applying regenerative braking, the temperature in Barcelona’s metro system has dropped by one degree Celsius. Although implementing MetroCHARGE costs about 8.6 million USD, TMB hopes to be able to recover it in 4-5 years through Save energy and profit from electric charging posts paid by the driver.

Metro systems around the world have the necessary electrical infrastructure in place to apply this approach, but not all use trains equipped with regenerative braking and train modifications are expensive. All trains in Barcelona have been equipped with this technology since the 1980s. Given that each train costs around $6.6 million and has an average lifespan of 35 – 45 years, the transit operator needs to include regenerative braking. in medium and long-term plans.

In addition to cost, there are many other challenges such as finding optimal locations to place inverters and charging towers in crowded urban areas. The biggest difficulty is reaching an agreement with city halls to access public spaces to place charging posts.

One of the main barriers to the application of regenerative braking is the lack of data on energy levels and how much money can be saved if the technology is used. Learning from projects like MetroCHARGE can help cities understand the benefits of regenerative braking.