Earth Hour 2009

YouTube promoted the Earth Hour by changing its logo, and by adding a switch on/off feature near the title of each video, so that users can change the background color from white to black.
One of the least co-operative areas traditionally has been Alberta; in 2008, Calgary's power consumption went up during Earth Hour. The trend continued in 2011 when Edmonton's power usage also increased. While Calgary's power usage went down in 2011 during the event, electricity officials could not distinguish their readings between normal usage and a conscious attempt to participate.