In early 2023, both parties agreed to a criminal mediation with Jean-Yves Lourgouilloux, deputy public prosecutor in charge of environmental issues at the Marseille judicial court. It resulted in a promising protocol that provides for a seasonal adaptation of freshwater discharges from the EDF hydroelectric power plant in Saint-Chamas in Europe’s second largest marine lagoon by surface area.
Turbine operation stopped in summer
The energy company is retaining its annual authorization for discharges of 1.2 billion cubic meters and 60,000 tons of silt to ensure, in the event of a peak in consumption, the hydroelectric production of the Durance-Verdon chain of which this power station is the last link. But Saint-Chamas will no longer operate turbines from June 1 to August 31, a very sensitive period for the natural environments of the pond, and in limited volumes and subject to conditions of compliance with salinity levels, between April 1 and May 31 and from September 1 to 15. Beyond that, during the fall and winter, discharges will be authorized, subject only to the condition that the salinity never falls below 15 grams per liter. Scientific monitoring will assess the effects. According to EDF, 6 million kWh of renewable energy have been lost since 2006 due to the restrictions imposed to preserve the Berre pond.
Constrained but more flexible
Raphaël Grisel, Director General of GIPREB, is pleased that EDF implemented the foundations of this agreement this summer. The pond is doing better despite the high temperatures in Provence.At this summer outing, the salinity is 30 grams per liter, the rate considered most favorable to respect the environment. We are now returning to the usual discharge regime, depending on energy needs and climatic conditions. We hope that EDF will not have to run the turbine at full capacity this winter because the pond is evolving favorably.“. For Pascale Sautel, Director of Concessions-EDF Hydro Méditerranée, the agreement, applicable until 2027, stems from a “constructive and win-win dialogue». «Compared to the previous situation, we certainly no longer have to operate turbines in the summer, but we have greater flexibility and operating flexibility in the winter period, thanks to reduced constraints on our weekly quotas. It was of paramount importance to defend this decarbonized production, the main source of renewable energy in the region.».
A larger project
The step, a major one to save the Berre pond, remains “transitional” for GIPREB, “complementary” for EDF. Studies are continuing in parallel for the creation of a water diversion that would guarantee electricity production, protect the lagoon and meet other uses (agriculture, industry, replenishment of water tables, drinking water supply, etc.). Announcements could be made in 2025 after a pre-consultation on the options envisaged. The project would cost between 1 and 1.7 billion euros.If it comes to fruition, we will be able to obtain 460 GWh of additional production by freeing ourselves from the constraints on the Salon-de-Provence and Saint-Chamas power stations.“, says Pascale Sautel. But like Raphaël Grisel, she admits that this achievement is part of “in a longer time».
Source: www.usinenouvelle.com
