In North America, the energy spent in uselessly lighting up the sky costs about a billion dollars each year. This is a pure waste of energy that also increases greenhouse gas emissions when fossil fuels are used to produce the electricity, which is generally the case.
Here in Quebec, more light is produced per inhabitant than anywhere else in the world. It has thus been estimated that 700 GWh could be saved annually in this province by improving lighting management. This amount of energy represents the annual electric heating bill for about 20,000 homes. All this waste costs over 50 million dollars per year!