France Will Turn off Office Lights at Night, Save Enough Electricity to Power 750,000 Homes

Starting this July, all non-residential buildings in France will be required to turn off all the lights an hour after the last worker leaves (how will someone turn off the lights if they're already gone? Someone explain to me why the law is written this way). This simple step will save gigantic amounts of energy—the equivalent of powering 750,000 homes.