A French minister has announced that air-conditioned shops in France will have to keep their doors shut to save energy or risk a fine of €750 (£635).
"Leaving doors open with air conditioning on led to 20% more energy consumption and (it) is absurd. A decree confirming the decision will be issued in the coming days," said Agnès Pannier-Runacher, the minister for ecological transition.
The announcement came after mayors of several cities, including Paris and Lyon, declared a similar directive during the country's heatwave last week.
"An aberration that must cease in the context of the climate emergency and energy crisis," declared Anne Hidalgo, the socialist mayor of Paris, last week.
Municipal police in the capital have already begun issuing €150 fines after Dan Lert, a deputy mayor in charge of the green transition in Paris, and the rest of the council expressed outrage over a "vast, irresponsible waste of energy", reports The Guardian.
French electricity is cheap because of the country's use of nuclear power, which produces about 70% of its needs, but the Russian gas crisis has prompted the president, Emmanuel Macron, to demand an energy "sobriety programme".
Retail outlets including major supermarkets have already agreed a plan under which they will switch off illuminated signs "as soon as the store closes" and "systematically reduce lighting intensity" by reducing shopfloor lighting levels.
Public premises will also be required to set thermostats higher in summer and lower in winter, while the public will be expected to turn off their wifi router and TV when they are away and switch off lights in rooms they are not using.
As part of the plan, aimed at reducing French power consumption by 10% within two years, Pannier-Runacher said on Sunday she would also issue a decree banning illuminated advertising between 1am and 6am everywhere except in railway stations and airports.
Yves Marignac, of the négaWatt thinktank, which recommends ways to reduce energy consumption, told France Info public radio the minister's announcements did not amount to "miracle measures" but were certainly more than symbolic.
"We are talking about measures likely to reduce consumption by a few per cent in a sector which itself represents a few per cent of French consumption," he said. "But it's important precisely because it's only by working all the levers that we will collectively achieve this objective."
Marignac added that what was also significant in Pannier-Runacher's remarks was the implicit reminder that "we have lived for decades in this promise of abundant energy, and have completely lost sight of the reality of our energy consumption".
Closing the doors of air-conditioned commercial premises was obviously "common sense", he said. "When a government has to remind us of this, it shows how far down the cheap, harmless energy route we have travelled."