How to ration electricity consumption in France? Although more than half of the nuclear reactors are currently closed for maintenance or corrosion problems, a defense council on energy supply chaired by Emmanuel Macron will be held this Friday. Objective: avoid blackouts and temporary outages.
Between the avenues considered by the government and the power regulator, voltage reductions would be a lower cost solution. This is what Agnès Pannier-Runacher mentioned in particular on Tuesday in France Inter.
The electrical voltage is the magnitude that measures the electrical intensity of an installation, that is, the amount of electricity available. In France, the tension is from a decree of 1996 of 230 volts as in all of our European neighbors. Previously it was 220 volts but it has been increased to harmonize the voltage at a European level.
Devices that work longer
Historically, this voltage was 110 volts, but it was increased in the 1950s to save energy. Higher voltage reduces electricity loss. Some countries in the world are still on 110 volts, the original voltage imposed by Thomas Edison. This is the case in the United States whose inhabitants were already largely equipped with household appliances during the transition to 220 volts. To keep millions of Americans from switching between washing machines and vacuum cleaners, the tension has never shifted across the Atlantic.
If, in France, the voltage is officially 230 volts, the voltage is not constant in individuals. According to Enedis, there is a tolerance of plus or minus 10% on the available voltage. Therefore, the voltage in our electrical outlets can vary between 207 and 253 volts. This voltage also oscillates permanently without users realizing it.
When these brownouts occur, light intensity drops and battery-powered devices take longer to charge, for example. But these voltage drops do not save energy, at least not on the end users’ side.
A gain close to zero
For some devices such as radiators, clusters or washing machines, a drop in voltage can certainly lead to a temporary drop in electricity consumption. But these devices will take more time for their resistance to reach the desired temperature. Therefore, the only really effective measure in terms of sobriety is to reduce the temperature.
Regarding other types of devices such as televisions, computers or LED lamps, here again, a drop in voltage should not produce a drop in consumption. In these devices, a 5% drop in electrical voltage should even be transparent. Its power system is said to be “switching”, that is, it stores the energy received before releasing it in a secondary circuit. If the voltage drops suddenly, the device turns off. But if it decreases slightly, the device will compensate for the voltage drop by consuming more electricity. The gain is finally close to zero.
The benefit of a voltage drop refers to the network. Instead of producing enough to send 230 volts to all users, the electricity producer whose capacities are reduced (which is the case with EDF at the moment) reduces the amounts sent to each one instead of depriving some of electricity. A transparent reduction for the end user if it is kept at reasonable levels (10 volts as mentioned by the Minister). The only risk for our appliances and our domestic installation would be sudden voltage variations with sudden surges.
Source: BFM TV
