Inspenet, August 30, 2023.
Iberdrola transformed the subway turnstiles into power generators
To commemorate “European Wind Day” in June, the Paris metro converted six access turnstiles into underground wind turbines over two days, generating more than 2,000 Wh of electricity through passenger movement.
Iberdrola carried out this initiative at the Miromesnil station, not only to promote renewable energy and its various applications, but also to highlight how engineering can transform public infrastructure to fulfill multiple functions for the benefit of sustainability.
These Paris underground turbines, developed in partnership with engineering students from Lille, they were not driven by the wind nor did they have the intention of setting a world record for energy production, but rather they were part of the “Turn to green” campaign, which aims to demonstrate “that energy is all around us and that there are many alternative ways of generating it” according to the director from Iberdrola France, Reginald Thiebaut.
“The primary objective was to raise public awareness about the importance of renewable energies in our energy mix through a unique experience: creating energy through a simple daily gesture such as taking the subway,” he adds.
In this way, an ingenious solution was devised to install these customized and unique wind turbines in the world in just a few hours, replacing the conventional turnstiles of the Paris metro and converting the movement generated by passengers into electricity .
The design process presented a challenge for the students, since generating electricity from a movement that usually occurs in fractions of a second is not an easy task. “We had to think of a system that would make the motor that generates electricity spin faster and longer,” says Thiebaut.
The solution adopted consisted of implementing a flywheel with a thick and heavy disc that was activated by rotating the turnstile. This disc, in turn, put into operation a gear system known as an “epicyclic gear train” or planetary. This mechanical configuration, traditionally used in gearboxes, had the ability to amplify the rotation speed of the system to which it was connected.
In addition to the mechanical and electrical components, the Lille students also focused on the design of the turbines and their striking blades, which were made of metal.
A total of six turnstiles were arranged in a series configuration and connected to various batteries. The energy generated over 48 hours was used to power the screens located on each side of the turnstiles. Although these figures are considerably removed from the megawatt levels generated by traditional wind turbines, the potential of the system is not without interest.
“In two days, 27,000 users produced more than 2,100 Wh. It may seem like a small sum, but if it were deployed throughout the entire metro network, we could produce 150 MWh in a year and provide electrical heating for a four-person household for ten years,” calculates Reginald Thiebaut.
After the successful initiative in the Paris metro, Iberdrola is considering the option of reusing these six “wind turnstiles” in events and exhibitions related to energy and the environment, as well as applying them in campaigns carried out in other metro stations. in all Europe.