Since November 1, 2025, the French electricity distribution company Enedis is changing the way off-peak hours are structured, a system that had remained largely unchanged since the 1960s. Off-peak hours, which previously always occurred at night, are now being partially shifted to midday. This change is part of a new electricity network usage tariff (TURPE 7) introduced by the Energy Regulation Commission (CRE) in March 2025. The reform aims to align electricity consumption with the production of renewable energy, particularly solar power, which peaks during the day. As a result, some devices programmed to operate at night may now be running during standard rate hours without any warning. The original off-peak system was created to manage the French electricity grid when nuclear power was the main source of energy. Nuclear plants cannot be easily stopped or started, so encouraging consumption during nighttime hours helped balance the grid. However, with the rise of solar energy, the dynamics of electricity production and consumption have changed. Solar power is most abundant during the day, creating a surplus that can drive electricity prices below zero in some cases. To address this, the CRE recommended shifting off-peak hours to match solar production peaks, which occur during the day in spring and summer. This reform has practical effects for households. Devices such as water heaters, washing machines, and electric vehicles that were programmed to operate at night may now be running during standard rate hours if not manually adjusted. The number of off-peak hours per day remains the same—eight hours, including at least five consecutive hours at night—but their distribution will change gradually until October 2027, depending on the location and season. The challenge lies in ensuring that household equipment is updated to reflect these new time slots, as many devices are still set to the old schedule. Consumers are advised to check their electricity bills, their supplier’s online portal, or their Linky smart meter to confirm the new off-peak hours assigned to their home. These time slots are determined locally by Enedis and can vary between neighboring homes. The reform represents a major shift in how electricity is managed in France, adapting a system originally designed for nuclear energy to accommodate the growing influence of solar power. This change highlights the evolving nature of the French electricity network, which now must balance two very different production rhythms: the steady output of nuclear plants and the variable, sun-dependent generation of solar energy.