Who says winter, says dropping temperatures and turning on the heaters. The Mons Frédéric-Estève high school, providing training in automotive and transport professions, does not escape seasonality. The difference is that this winter, the establishment with 370 students, 70 apprentices and 60 teachers is heated using the heat naturally present underground: geothermal energy.
This change has been in effect since the beginning of November, upon returning from the All Saints holidays. The inauguration of this new system took place on Tuesday, December 3, in the presence of the Landes vice-president of the Region Renaud Lagrave, the engineer in charge of the energy transition for the Nouvelle-Aquitaine Region Xavier Pujos , and representatives of the service provider Inter Énergies.
The same radiators
After a month of use, the principal of the establishment, Éric Delmotte, assures us that “we don’t notice anything. There is no difference.” The radiators in the classrooms did not need to be renewed. The permutation of natural gas with geothermal energy will be felt more with the arrival of summer, with geocooling. In other words a renewable cooling system thanks to the same geothermal installation which should allow a loss of around 6°C compared to the outside temperature during the summer period.
A significant gain for schools, all of which lack air conditioning, but are increasingly subject to extreme heat at the start and end of the school year. “In addition to the substitution, we gain in comfort,” underlines Xavier Pujos, who came to present the installation.
The changes are taking place inside the boiler room and a new room built a stone’s throw from a borehole drilled on the site of the establishment in 2021. The hot water rises straight from the water table to the local by pipes. Once at the surface, the calories in this water at 15.3°C are converted into energy by a heat pump. The latter is then injected into the establishment’s heating circuit. The water, for its part, returns to where it came from in the water table through a second borehole.
Half the price
This so-called doublet geothermal installation will be maintained by the service provider Inter Énergies, present in Mont-de-Marsan. An operation worth 1.3 million euros net for the Region, with a return on investment of twelve years. This energy substitution should allow the establishment a reduction of 40 to 50% in the overall cost compared to its consumption of natural gas. Also a way to gain “energy independence”, as Renaud Lagrave reminds us.
In addition to the bill, the establishment must divide its annual CO2 emissions by nine, going from 230 tonnes to 27. “We try to develop geothermal energy wherever we can by launching studies. There is an interesting return on investment. Geothermal energy is gaining momentum,” assures the Landes vice-president of the Regional Council.
Where is geothermal energy in Landes high schools?
In 2011, the Saint-Exupéry establishment in Parentis-en-Born was the first high school in New Aquitaine equipped with geothermal energy. Since then, of the 17 public high schools in Landes, six are heated in this way: the Haroun-Tazieff establishments in Saint-Paul-lès-Dax; Borda in Dax; Jean-Garnier in Morcenx; and South of Landes in Saint-Vincent-de-Tyrosse (in addition to Saint-Exupéry and Frédéric-Estève). A rate which allows Renaud Lagrave and Xavier Pujos to confidently assert that this is the department of Nouvelle-Aquitaine, even in France, with the most high schools equipped with geothermal energy, knowing that the Landes geology facilitates this type of facilities.
Three other Landes high schools are currently being studied to probably switch to geothermal energy. These are Charles-Despiau in Mont-de-Marsan, Gaston-Crampe in Aire-sur-l’Adour and Jean-Taris in Peyrehorade.
For certain establishments, such as the agricultural high schools of Chalosse in Mugron and Roger-Duroure in Sabres, the use of geothermal energy proves more complicated. Other substitutions to replace fossil fuels are possible, such as biomass, already implemented in the Hector-Serres high schools, in Oeyreluy, and Ambroise-Croizat, in Tarnos.
