Pierre-Yves Ancion follows the Grand Paris Express project and its developments like no other. And for good reason: this engineer is one of the designers of the tool that measures the carbon footprint, down to the smallest detail.
CarbOptimum is a specific topic that deserved an explanation with one of its creators, Pierre-Yves Ancion.
CarbOptimum, careful monitoring of the carbon footprint
Specifically designed to monitor the carbon footprint of the Grand Paris Express drawing inspiration from the methodological elements developed by theADEME or other international methodologies such as the Greenhouse Gas Protocol, the tool, which takes the form of a large spreadsheet, fits on a simple USB stick. Its configuration, which requires the introduction of many hypotheses, sheds light on the decisions taken by the Société du Grand Paris and evaluates their impact on the environment. And this since 2012, well before the work began.
A deep awareness of the environment
Director of Studies at STRATEC, Pierre-Yves Ancion arrives from Brussels at the Gare du Nord. Instead of taking public transport, our man walks an hour to the Fabrique du métro in Saint-Ouen. As he walks, the spatial planner observes the city: intramural Paris in its elegant Haussmannian garb, and Greater Paris, in complete reconfiguration.
Pierre-Yves Ancion has always had a keen sensitivity for the environment, as a sanctuary to be preserved. To what extent does man denature his ecosystem? A significant demand in Belgium, where the population density is three times higher than in France. Growing up in the countryside, he will spend his whole life in the open air, surrounded by green vegetation and blue water. But outside or in the office, he doesn’t let go of the red thread of his career: assessing man’s impact on the environment.
From the rivers of New Zealand to the Grand Paris Metro
It was in Auckland, New Zealand that the qualified engineer completed his thesis, which focused on the measurement of pollution in rivers, mainly in urban areas. For four years he has honed his thinking about him, observing residents who live mostly outside. ” New Zealanders take advantage of their gardens, are numerous in the parks, play rugby and sail in all seasons… And finally, they stay very little at home. There I understood that light was a need for everyone… And not just for me! Pierre-Yves Ancion also notes the limitations of this model, which is decidedly energy intensive. The New Zealanders aspire to the American-style pavilion, large volumes that promote energy dispersion and the artificialization of the land. Not to mention urban sprawl, a spatial organization that relies on the automobile. Fortunately, the population density is six times lower than that of France. Furthermore, being the volcanic island, it can count on geothermal energy, a formidable source of energy.
Europe benefits neither from such vast spaces nor from such a generous geology. It is therefore essential to curb the artificialisation of the soil and the use of fossil fuels. It’s time for sobriety. Voices are heard questioning these suburban wastes. Pierre-Yves Ancion nonetheless remains convinced of the benefits of the outdoors and its luminosity, particularly in countries where it is rare. But then, how to live in a pleasant and bright environment without resorting to the energy-intensive pavilion? This is where the Grand Paris Express project and CarbOptimum come into play.
A table of 1500 rows
Pierre-Yves Ancion has accompanied the Grand Paris adventure from the beginning. When the new subway was just a project on paper, we wanted to equip the project with a carbon measurement tool. ” Since 2009, the strategic environmental study has served as a wake-up call: this project was of such magnitude that assessing its carbon footprint would have been very difficult.says the engineer. In our benchmark, we realized that none of the existing tools were suitable. We have therefore specially developed it. For transport infrastructure, this GHG emission assessment exercise is the largest in existence. In 2012, an initial assessment was carried out on the basis of forecast data. But we didn’t know then, for example, what kind of concrete would be used. When the work started, the real data was re-entered and the balance sheet was updated. Furthermore, the prime contractors are called upon to compile some of the 1500 lines of CarbOptimum.
First of all, the new subway, like any construction site, releases CO2 into the atmosphere. This is largely due to the concrete required for the construction of tunnels and stations, even if everything is done to limit emissions: the Société du Grand Paris has encouraged innovation across the board and the use of fiber cement or low-carbon materials derive from this voluntarism. In a second phase, once the Metro is in service, carbon emissions will be avoided in a very significant way. So much so that the balance between CO2 emissions produced and those avoided announces a benefit of around 14.2 million tonnes of CO2 in 2050, according to a conservative scenario.
Trade suburban living for an eco-district
In these projections there are the cars that will remain in the garage for the benefit of the metro. But we also know, thanks to CarbOptimum, that most of the carbon savings will be made elsewhere.
To understand this, Pierre-Yves Ancion takes us to the eco-district opposite the Fabrique du métro. Here, near the recent Mairie de Saint-Ouen station on line 14, which is being extended to Saint-Denis-Pleyel, dense buildings have been built at the foot of an immense park. Often equipped with terraces or balconies, new buildings are designed to let in light. ” A person who has the metro nearby can do without a car and occasionally take a shared vehicle to go to Ikea, decrypts the director of studies. It will accept to live in a smaller but well isolated habitat and will not need a garden thanks to the large park below. And it will benefit from the proximity of jobs, facilities and shops. It is because it goes into detail that CarbOptimum has made possible this global analysis of the city, which goes beyond the subway.
The Grand Paris Express kit
It is not enough to build a new station, and neither is 68, if they are not accompanied by well-framed urban dynamics. This is what is at stake in the station districts, along lines 15, 16, 17 and 18. Life is made easier with the arrival of the metro in dense and mixed eco-districts, and greenery at the back of the houses themselves , as an alternative to the pavilion which imposes the use of the private car and which contributes to urban sprawl.
With his eyes fixed on the impact of the work and development projects that are emerging, the father of CarbOptimum calculates, year after year, the carbon trajectory of the new Metro. But be careful, he warns, not to rely solely on it. « Everyone should roll up their sleeves. This project will save between 700,000 and one million tonnes of CO2 equivalent each year. It is important, of course, but far from sufficient to achieve national objectives in terms of reducing greenhouse gas emissions. The Grand Paris Express will not be able to fix everything on its own, it must initiate a broader change in behavior among the residents of Ile-de-France. »
Less pessimistic today
This is undoubtedly the reason why Pierre-Yves Ancion believes that we will not be able to do without a systemic change concerning the way we move and travel, but also of living or eating… the engineer thought about it for a long time pledged time on global warming and how to stop it. He was already devastated in the carefree time when this danger was observed from afar. ” Since the early 2000s, we already had a lot of evidenceremember. Scientists sounded the alarm, but their cries met with little public response “. Now he admits he’s pleasantly surprised by the progress made in raising awareness. The topic now fuels conversations, it also figures in policy choices. ” Surprisingly, I’m less pessimistic than 20 years agosays our expert. I didn’t think at the time that in 2020 we would be able to reduce our greenhouse gas emissions, even by a small percentage! »
